Clinical Cancer Research Bridging the Lab and the Clinic in Cancer Medicine Infection and Cancer: Biology, Therapeutics, and Prevention
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Cancer Research Clinical Cancer Research
Cancer Epidemiology Biomarkers & Prevention Molecular Cancer Therapeutics
Molecular Cancer Research Cancer Prevention Research
Cancer Prevention Journals Portal Cancer Reviews Online
Annual Meeting Education Book Meeting Abstracts Online
This Article
Right arrow Abstract Freely available
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow reprints & permissions
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Altorki, N. K.
Right arrow Articles by Dannenberg, A. J.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Altorki, N. K.
Right arrow Articles by Dannenberg, A. J.
Clinical Cancer Research Vol. 11, 4191-4197, June 1, 2005
© 2005 American Association for Cancer Research

Cancer Therapy: Preclinical

Chemotherapy Induces the Expression of Cyclooxygenase-2 in Non–Small Cell Lung Cancer

Nasser K. Altorki1, Jeffrey L. Port1, Fan Zhang2, Dragan Golijanin3, Howard T. Thaler4, Anna J. Duffield-Lillico4, Kotha Subbaramaiah2 and Andrew J. Dannenberg2

Authors' Affiliations: 1 Department of Cardiothoracic Surgery and 2 Medicine, Weill Medical College of Cornell University; and 3 Urology and 4 Epidemiology and Biostatistics, Memorial Sloan-Kettering Cancer Center, New York, New York

Requests for reprints: Andrew J. Dannenberg, Department of Medicine, Weill Medical College of Cornell University, Room F-206, 525 East 68th Street, New York, NY 10021. Phone: 212-746-4403; Fax: 212-746-4885; E-mail: ajdannen{at}med.cornell.edu.


   Abstract
Top
 Abstract
Materials and Methods
 Results
 Discussion
 References
 
Purpose: To determine the effect of taxane-based chemotherapy on intratumoral levels of cyclooxygenase-2 (COX-2) and prostaglandin E2 (PGE2) in patients with non–small cell lung cancer (NSCLC).

Experimental Design: Lung specimens obtained at the time of surgery were used to measure levels of COX-2 and PGE2 in tumors and adjacent nontumorous tissues in three subsets of NSCLC patients who underwent: (A) surgical resection only (n = 16); (B) surgical resection after preoperative taxane-based chemotherapy (n = 13); or (C) surgical resection after preoperative chemotherapy coadministered with the selective COX-2 inhibitor, celecoxib 400 mg bid (n = 17).

Results: Levels of intratumoral PGE2 were nearly 3-fold higher among patients who received preoperative chemotherapy compared with those treated by surgery alone (P < 0.001). This difference was abrogated by the addition of celecoxib to preoperative chemotherapy (P < 0.001). Amounts of intratumoral COX-2 were ~3-fold higher in groups of patients who received preoperative chemotherapy with celecoxib (P < 0.0001) or without celecoxib (P < 0.001), compared with the group who underwent surgical resection only. Importantly, statistically significant positive correlations between COX-2 and PGE2 were observed in the surgery only (r = 0.502, P = 0.047) and preoperative chemotherapy groups (r = 0.740, P = 0.004); this correlation was abrogated when celecoxib was given with chemotherapy (r = 0.005, P = 0.98).

Conclusions: Treatment with chemotherapy led to increased amounts of COX-2 and PGE2 in NSCLC. Cotreatment with celecoxib abrogated the increase in levels of PGE2 but not COX-2 induced by chemotherapy. Importantly, these results clearly show that levels of a pharmacologic target (i.e., COX-2) can be affected by both the intrinsic molecular properties of a tumor and therapy.

Key Words: cyclooxygenase-2 • prostaglandins • neoadjuvant chemotherapy

There are two isoforms of cyclooxygenase (COX). The COX enzymes catalyze the first step in the synthesis of prostaglandins from arachidonic acid. COX-1 is constitutively expressed in most normal tissues and seems to mediate various physiologic functions (1). In contrast, COX-2 is absent in most normal tissues but is induced by a variety of mitogenic and proinflammatory stimuli (2–6). Increased levels of COX-2 and prostaglandin E2 (PGE2) have been observed in a variety of malignancies, including non–small cell lung cancer (NSCLC; refs. 7–19). Several mechanisms can potentially account for the tumor promoting effects of COX-2–derived prostaglandins. Prostaglandins can enhance tumor growth and metastasis by stimulating cell proliferation, angiogenesis, and invasiveness in addition to inhibiting apoptosis and immune surveillance (7, 20–26). Importantly, the formation and growth of tumors is reduced in mice engineered to be COX-2 deficient (27–29). Moreover, selective inhibitors of COX-2 suppress the growth of experimental tumors (7, 30–34).

In addition to its potential role in tumor promotion and progression, overexpression of COX-2 may also reduce the response of malignant cells to cytotoxic therapy. For example, we have previously shown that taxanes induce COX-2 and prostaglandin biosynthesis in vitro and postulated that this may reduce the efficacy of taxanes (35). Theoretically, coadministration of a selective COX-2 inhibitor with taxane-based chemotherapy would overcome any decrease in efficacy related to taxane-mediated induction of COX-2. In support of this hypothesis, the addition of a selective COX-2 inhibitor augmented taxane-mediated inhibition of tumor growth in an experimental model of NSCLC (36). A phase II clinical trial suggested that the addition of a selective COX-2 inhibitor might enhance the response to preoperative paclitaxel and carboplatin in patients with NSCLC (37).

Despite the above findings, little is known about the effects of cytotoxic chemotherapy on levels of COX-2 and PGE2 in human malignancies. In the current study, levels of COX-2 and PGE2 were determined in three subsets of NSCLC patients who received different treatments: (a) primary surgical resection without preoperative chemotherapy, (b) surgical resection after preoperative taxane-based chemotherapy, and (c) surgical resection after preoperative taxane-based chemotherapy coadministered with the selective COX-2 inhibitor celecoxib.

To our knowledge, this study provides the first evidence in humans that chemotherapy leads to significant increases in levels of intratumoral COX-2 and PGE2. Cotreatment with celecoxib abrogated the increase in levels of PGE2 but not COX-2 induced by chemotherapy. Importantly, these results clearly show that levels of pharmacologic targets (e.g., COX-2) within tumors can be affected by both the intrinsic molecular properties of the tumor and therapy.


   Materials and Methods
Top
 Abstract
 Materials and Methods
Results
 Discussion
 References
 
Materials. Rabbit polyclonal anti–COX-2 antiserum (PG-27) was from Oxford Biomedical Research (Oxford, MI) and COX-2 blocking peptide was from Cayman Chemical Co. (Ann Arbor, MI). Antisera to COX-1 and ß-actin were from Santa Cruz Biotechnology, Inc. (Santa Cruz, CA). Indomethacin and 3,3'-diaminobenzidine were from Sigma Chemical Co. (St. Louis, MO). Secondary anti-rabbit biotinylated antibody was from Vector Laboratories, Inc. (Burlingame, CA). Streptavidin-horseradish peroxidase was from DAKO Corp. (Carpinteria, CA). Superfrost Plus slides were from Fisher Scientific (Pittsburgh, PA).

Patients and tissue specimens. Tissue specimens were obtained from a total of 46 NSCLC patients (16 surgery only, 13 surgery after chemotherapy, and 17 surgery after chemotherapy and celecoxib) who underwent surgery at the New York Presbyterian Hospital. There were no major differences among the three groups with respect to tumor cell type and stage distribution (Table 1). The 17 patients who underwent surgery after chemotherapy and celecoxib were part of a phase II clinical trial that has been previously described (37). Tumor tissue was not available from seven additional patients in this study who had significant pathologic responses. Briefly, patients in this trial received two cycles of paclitaxel and carboplatin 21 days apart. Paclitaxel at 225 mg/m2 was given as a 3-hour infusion followed by a 1-hour i.v. infusion of carboplatin dosed to an area under the curve of 6 by the Calvert formula. Celecoxib was given orally at a dose of 400 mg twice daily, starting on the first day of chemotherapy until the morning of the surgical procedure. This protocol was reviewed and approved by the institutional review board at the Weill Medical College of Cornell University, and informed consent was obtained from all patients. Separate institutional review board approval was obtained to carry out COX enzyme and PGE2 analyses on surgically resected lung tissues from patients who underwent surgery only or patients who received preoperative paclitaxel and carboplatin before undergoing surgery. For all patients who received preoperative chemotherapy, thoracotomy was done 3 to 6 weeks after the second cycle of chemotherapy. Samples of primary tumor and adjacent nontumorous lung at least 5 cm away from the tumor were immediately snap frozen and stored at –80°C until analysis.


View this table:
[in this window]
[in a new window]
  		Table 1. Clinical and pathologic characteristics

 
Prostaglandin E2 measurements. Levels of PGE2 were determined as in previous studies (37). Briefly, frozen tissue was thawed in ice-cold buffer containing 150 mmol/L NaCl, 100 mmol/L TBS (pH 8), 1 mmol/L EDTA, and 10 µmol/L indomethacin. Indomethacin, a dual inhibitor of COX-1 and COX-2, was added to prevent ex vivo synthesis of PGE2. Following homogenization, tissues were sonicated twice for 20 seconds on ice and centrifuged at 10,000 x g for 10 minutes at 4°C to remove particulate material. The protein concentration of the supernatant was measured using the Lowry protein assay kit (Sigma Chemical). Amounts of PGE2 in the supernatant were determined by enzyme immunoassay according to the manufacturer's instructions (Cayman Chemical). Levels of PGE2 were normalized to protein concentrations in the supernatant.

Western blotting. Frozen tissue was thawed in ice-cold lysis buffer [150 mmol/L NaCl, 100 mmol/L Tris (pH 8.0), 1% Tween 20, 50 mmol/L diethyldithiocarbamate, 1 mmol/L EDTA, 1 mmol/L phenylmethylsulfonyl fluoride, 10 µg/mL trypsin inhibitor, and 10 µg/mL leupeptin]. Tissues were sonicated for 20 seconds on ice and centrifuged at 10,000 x g for 10 minutes at 4°C to remove the particulate material. The protein concentration of the supernatant was measured using the method of Lowry et al. (38). Immunoblot analyses for COX enzymes and ß-actin were done using methods described in previous studies (35). A computer densitometer (Gel Doc 2000, Bio-Rad, Hercules, CA) was used to quantify the density of the bands. Amounts of COX-2 are expressed in arbitrary units.

Immunohistochemistry. This was carried out using methods that have been reported previously (39). Neutral buffered formalin-fixed tissue was embedded in paraffin. Tissue sections (4 µm) were prepared using a microtome and mounted on Superfrost/Plus slides. Immunohistochemical analysis was done within 24 hours of the sections being cut. Sections were deparaffinized in xylene, rehydrated in graded alcohols, and washed in distilled water. Antigen retrieval was done by steaming the sections in 10 mmol/L citric acid (pH 6.0) for 30 minutes. Subsequently, endogenous peroxidase activity was blocked with 3% hydrogen peroxide. Slides were washed thrice in PBS and blocked for 20 minutes with 2% bovine serum albumin. Tissue sections were incubated with antiserum to COX-2 at a 1:1,000 dilution (2% bovine serum albumin in PBS) for 18 hours at 4°C. Control sections were incubated with COX-2 antiserum preabsorbed with a 100-fold excess of blocking peptide. After being washed thrice with PBS, the sections were incubated with biotinylated anti-rabbit antibody at a 1:500 dilution for 1 hour at room temperature. The slides were washed thrice in PBS and labeled using 1:500 streptavidin-horseradish peroxidase for 1 hour at room temperature. The reaction was visualized using 3,3'-diaminobenzidine. Subsequently, the slides were rinsed in tap water and counterstained with hematoxylin. The slides were then dehydrated with ethanol, rinsed with xylene, and mounted.

Statistical analysis. The data for PGE2 levels (pg/µg protein) in normal and in tumor tissue and for COX-2 levels (arbitrary unit) were positive and had distributions that were skewed towards high values in each of the three groups. Because the data were skewed, means and SDs are not appropriate summaries of typical values of measurements within patient groups. We therefore present medians with nonparametric 95% confidence intervals (95% CI). Generalized {gamma} distributions, which allow for a great diversity in possible distribution shapes, were fit parametrically to the data by maximum likelihood using SAS Software Proc Lifereg (version 9.0, SAS Institute, Inc., Cary, NC). When generalized {gamma} distributions were fit to data for each patient group, the scale and shape variables for each measurement (PGE2 in tumor and adjacent normal tissues and intratumoral COX-2 expression) did not differ significantly between groups. This facilitated assessment of statistical significance of comparisons based on the location variables, which correspond to differences in the central values of log-transformed measurements. These differences are equivalent to the ratios of the central values on the original, raw data scale.


   Results
Top
 Abstract
 Materials and Methods
 Results
Discussion
 References
 
Patients included in this investigation underwent surgery between September 1997 and May 2002. Patient characteristics are listed in Table 1. Among the surgery-only cases, males and females were equally represented; however, most patients undergoing preoperative chemotherapy were female (69%), whereas the majority of patients who received celecoxib in addition to preoperative chemotherapy were male (59%). Adenocarcinoma was the most prevalent histology in all groups. In general, there were no major differences among the three groups with respect to cell type and stage distribution.

Chemotherapy increases amounts of intratumoral prostaglandin E2. The concentrations of PGE2 were measured in both tumor tissues and adjacent normal tissues in the three defined groups of patients. As displayed in Fig. 1, PGE2 levels in tumors were 2.78 times as high based on the fitted distributions among patients who received preoperative chemotherapy with median 384 pg/µg protein, and 95% CI (279-1,818) compared with tumors treated by surgical resection only with median 150 pg/µg protein (95% CI, 89-265; P < 0.001). Intratumoral PGE2 levels were 3.77 times as high among chemotherapy patients compared with patients who received preoperative chemotherapy + celecoxib with median 112 (95% CI, 69-193; P < 0.0001). Thus, as previously reported (37), the addition of celecoxib to chemotherapy led to a normalization of levels of intratumoral PGE2.



View larger version (13K):
[in this window]
[in a new window]
  		Fig. 1. Concentrations of intratumoral PGE2 are elevated in tumors from patients treated with preoperative chemotherapy compared with those treated by surgical resection alone and those treated with preoperative chemotherapy + celecoxib. At the time of surgery, tumor (T) and adjacent nontumorous (N) tissue were obtained from NSCLC patients who received surgery alone (n = 16), preoperative chemotherapy (n = 13), or preoperative chemotherapy and celecoxib (n = 17). Log-transformed data for each individual patient are displayed within study groups: S, surgery; C, preoperative chemotherapy; and X, preoperative chemotherapy + celecoxib. Levels of intratumoral PGE2 were increased in tumors from patients treated with preoperative chemotherapy compared with those treated by surgery alone (P < 0.001) and those treated with preoperative chemotherapy + celecoxib (P < 0.0001).

 
Chemotherapy increases cyclooxygenase-2 expression. In an attempt to elucidate the mechanism underlying the observed differences in intratumoral PGE2 in the three groups of patients, Western blots for COX-2 were done. Levels of COX-2 were 3.33 times as high based on the fitted distributions in tumors after preoperative chemotherapy with median 8.2 and 95% CI of 0.6 to 14.0 compared with tumors from patients treated with surgery only with median 2.2 (95% CI, 1.0-4.1; P < 0.001) and were 2.74 times as high in tumors among chemotherapy patients treated with celecoxib compared with tumors from patients who underwent surgery only with median 5.0 (95% CI, 3.6-7.0; P < 0.0001; Fig. 2). Thus, the increased levels of intratumoral PGE2 observed after preoperative chemotherapy were associated with a significant increase in amounts of intratumoral COX-2. Remarkably, the addition of celecoxib at 800 mg/d to chemotherapy reduced the levels of intratumoral PGE2 to those found in adjacent normal lung (Fig. 1) despite persistent overexpression of COX-2 in the tumors (Fig. 2). These findings are consistent with celecoxib inhibiting COX-2 enzyme activity not protein expression. In Fig. 3, representative results are shown from tumors in each of the three patient groups to illustrate the main findings of the study. Preoperative chemotherapy led to increased amounts of intratumoral COX-2 and PGE2 compared with tumors from patients who underwent surgery only. The addition of celecoxib to preoperative chemotherapy led to a significant reduction in intratumoral PGE2 although COX-2 levels were elevated compared with tumors from patients who underwent surgery only. In contrast to COX-2, levels of COX-1 were similar among the three groups. In untreated NSCLC, COX-2 is overexpressed in neoplastic epithelial cells (14, 17). Given the discovery that preoperative chemotherapy led to increased amounts of COX-2, immunohistochemistry was carried out to localize COX-2. Theoretically, chemotherapy might have altered expression in neoplastic cells, stroma, or both. As shown in Fig. 4, the expression of COX-2 was exclusively limited to neoplastic cells with no stomal staining. Immunoreactivity was lost when the antiserum to COX-2 was preincubated with a COX-2 blocking peptide.



View larger version (12K):
[in this window]
[in a new window]
  		Fig. 2. Amounts of intratumoral COX-2 were significantly higher in both patient groups treated with preoperative chemotherapy, with or without celecoxib treatment, compared with those treated by surgical resection alone. Levels of COX-2 were determined by immunoblot analysis and quantified in arbitrary units (a.u.). Log-transformed data for each individual patient are displayed within study groups: S, surgery; C, preoperative chemotherapy; and X, preoperative chemotherapy + celecoxib. Levels of COX-2 were increased in tumors after preoperative chemotherapy with (P < 0.0001) or without celecoxib (P < 0.001) compared with tumors from patients treated with surgery only.

 


View larger version (33K):
[in this window]
[in a new window]
  		Fig. 3. Preoperative chemotherapy, with or without celecoxib treatment, induced COX-2. Lanes 1 to 3, representative tumor samples from patients treated by surgical resection only. Lanes 4 to 7, representative tumor samples from patients treated by preoperative chemotherapy followed by surgical resection. Lanes 8 to 11, representative tumor samples from patients treated by preoperative chemotherapy + celecoxib followed by surgery. Levels of COX-2 and COX-1 were determined by immunoblot analysis. Intratumoral levels of PGE2 from the same cases (cases 1-11) were determined by enzyme immunoassay.

 


View larger version (117K):
[in this window]
[in a new window]
  		Fig. 4. COX-2 is expressed in neoplastic cells in NSCLC. Immunohistochemistry was used to evaluate COX-2 expression in tumor samples from patients treated with surgery alone or preoperative chemotherapy followed by surgery. Representative sections. A, adenocarcinoma treated by primary surgical resection. B, poorly differentiated squamous cell carcinoma after preoperative chemotherapy. Both show localization of COX-2 expression to neoplastic cells.

 
Chemotherapy-based induction of cyclooxygenase-2 and prostaglandin E2 occurs in a subset of patients with non–small cell lung cancer. As shown in the scatter plots in Fig. 5, chemotherapy-mediated induction of COX-2 and PGE2 was only observed in a subset of patients. For example, COX-2 levels were similar to those found in the surgery alone group (Fig. 5A) in ~7 of 13 patients in the chemotherapy only patients (Fig. 5B) and 12 of 17 patients treated with chemotherapy + celecoxib (Fig. 5C). However, a total of 11 of 30 patients who received preoperative chemotherapy with or without celecoxib had COX-2 levels that exceeded COX-2 levels in any patient in the surgery alone group.



View larger version (9K):
[in this window]
[in a new window]
  		Fig. 5. Scatter plots show the correlation between COX-2 and PGE2 levels in patients treated by (A) surgery only, (B) preoperative chemotherapy, or (C) preoperative chemotherapy + celecoxib. The positive correlation between COX-2 and PGE2 in the surgery and preoperative chemotherapy groups was abrogated when celecoxib was given with chemotherapy. Data for each individual patient are displayed within study groups: S, surgery; C, preoperative chemotherapy; and X, preoperative chemotherapy + celecoxib.

 
Cyclooxygenase-2 is the rate-limiting step in prostaglandin E2 synthesis in vivo. To determine whether COX-2 is a rate-limiting enzyme in PGE2 biosynthesis in NSCLC, the levels of intratumoral PGE2 were plotted against the amounts of COX-2 as determined by Western blotting for each of the three groups of patients. As seen in Fig. 5A and B, there was a positive correlation between levels of PGE2 and COX-2 levels in the surgery only group (r = 0.502, P = 0.047) as well as in patients treated by preoperative chemotherapy only (r = 0.740, P = 0.004). This positive correlation was abrogated when celecoxib was given with chemotherapy (r = 0.005, P = 0.98; Fig. 5C).


   Discussion
Top
 Abstract
 Materials and Methods
 Results
 Discussion
References
 
To our knowledge, this study provides the first evidence in humans that treatment with chemotherapy can enhance intratumoral levels of COX-2 and PGE2. This finding has both practical and theoretical implications. Previous studies have shown that levels of COX-2 and PGE2 are commonly increased in different tumor types (7–19, 40–43). Generally, the magnitude of these increases is quite variable both within and between tumor types (8, 11, 13, 39). The current findings imply that intratumoral levels of COX-2 and prostanoids need to be interpreted in the context of whether cytotoxic therapy was given before tissue acquisition.

Numerous in vitro studies have shown that either oncogene activation or tumor suppressor gene inactivation result in enhanced expression of COX-2 and increased synthesis of PGE2 (7, 40, 44, 45). An effort has been made to translate these in vitro findings to human tumors. For example, both overexpression of HER-2/neu and mutation of TP53 have been associated with elevated levels of COX-2 in human malignancies (44, 46, 47). Based on the findings in this study, it is clear that the ability to identify molecular determinants of COX-2 expression will be compromised if samples are obtained from subjects with varying treatment histories. Therefore, future correlative studies need to be done with a detailed knowledge of any treatment that was given before the tumor sample was obtained.

We observed a positive correlation between intratumoral COX-2 expression and PGE2 levels in patients who were treated with surgery alone (Fig. 5A) or preoperative chemotherapy followed by surgery (Fig. 5B). Notably, the addition of celecoxib 400 mg bid to chemotherapy abrogated this positive correlation (Fig. 5C). This dose was chosen because it was previously reported to cause a reduction in the number of colorectal adenomas in a clinical trial (48). These findings in human tissues are consistent with existing in vitro evidence that COX-2 is rate limiting for PGE2 synthesis in tumor cells. It is intriguing to note that the inductive effect of chemotherapy on levels of COX-2 and PGE2 was only observed in a subset of tumors. Tumor tissue was unavailable from patients who had significant pathologic responses to preoperative chemotherapy. This limited our ability to determine whether intratumoral levels of COX-2 correlated with clinical response. Differences in amounts of COX-2 following chemotherapy could simply reflect the biological heterogeneity of tumors. Alternatively, chemotherapy may have induced COX-2 and PGE2 in virtually all cases with normalization of levels in some tumors during the interval of time between the last dose of chemotherapy and surgery. Recently, levels of urinary PGE-M, a stable end metabolite of PGE2, were reported to reflect systemic production of PGE2 (49). Future studies can be done to determine if cytotoxic chemotherapy induces levels of urinary PGE-M. If so, serial measurements should help to further elucidate the relationship between chemotherapy and deregulated PGE2 production.

Another interesting question concerns the mechanism(s) underlying the observed increase in amounts of COX-2 in some tumors following chemotherapy. Both deregulated transcriptional and post-transcriptional mechanisms can affect levels of COX-2 (40, 50, 51). In fact, taxanes can both enhance COX-2 transcription and stabilize COX-2 message in vitro (35, 52). Previous studies have suggested that taxanes activate COX-2 transcription by an activator protein-1-dependent mechanism (35). Increased binding of HuR to the COX-2 3'-untranslated region was found to contribute to taxane-induced stabilization of COX-2 mRNA (52). Whether either of these mechanisms is operative in vivo should be evaluated. It also is important to acknowledge that the mechanism by which chemotherapy induces COX-2 in tumors in vivo may be quite different than the mechanism that was identified during short-term in vitro studies. For example, the increase in COX-2 following chemotherapy could be a nonspecific consequence of tissue injury. Interestingly, when compared with surgery alone, treatment with chemotherapy led to increased amounts of COX-2–derived PGE2 in tumorous but not in normal tissue. This finding is consistent with the ability of cytotoxic chemotherapy to cause greater injury of tumor versus normal cells.

The primary observation of this study, that taxane-based chemotherapy induces COX-2 and PGE2 in patients with NSCLC, may have important clinical implications. Although cytotoxic therapy may result in cell death in a population of cancer cells, it might induce or repress a number of factors that influence therapeutic efficacy or even further accelerate the emergence of a metastatic phenotype. For example, COX-2 expression may not only inhibit chemotherapy-mediated apoptosis but also promote metastatic clones by enhancing the expression of CD44 and matrix metalloproteinases (53, 54). Importantly, in an era of heightened interest in targeted therapy, our data strongly suggest that levels of molecular targets may not be static. This study suggests that molecular changes induced by cytotoxic therapy may affect either the optimal dose or schedule of administration of a targeted therapeutic.

Recently, prolonged use of selective COX-2 inhibitors has been associated with an increased risk of cardiovascular complications including myocardial infarction and stroke. In every clinical situation, the potential risk/benefit ratio of a medication needs to be considered. This is certainly true for NSCLC patients who frequently have a very poor prognosis. Although the current study was not designed to evaluate clinical efficacy, it did show the ability of celecoxib to effectively suppress intratumoral COX-2 activity. Clinical trials are needed to determine whether the promising anticancer activity of celecoxib shown in preclinical studies (7, 40) translates into clinical benefit for cancer patients.


   Footnotes
 
Grant support: National Cancer Institute grant P01 CA77839 and the Center for Cancer Prevention Research.

The costs of publication of this article were defrayed in part by the payment of page charges. This article must therefore be hereby marked advertisement in accordance with 18 U.S.C. Section 1734 solely to indicate this fact.

Received 1/14/05; revised 3/ 7/05; accepted 3/14/05.


   References
Top
 Abstract
 Materials and Methods
 Results
 Discussion
 References
 

  1. Smith WL, DeWitt DL, Garavito RM. Cyclooxygenases: structural, cellular, and molecular biology. Annu Rev Biochem 2000;69:145–82.[CrossRef][Medline]
  2. Kujubu DA, Fletcher BS, Varnum BC, Lim RW, Herschman HR. TIS10, a phorbol ester tumor promoter-inducible mRNA from Swiss 3T3 cells, encodes a novel prostaglandin synthase/cyclooxygenase homologue. J Biol Chem 1991;266:12866–72.[Abstract/Free Full Text]
  3. Jones DA, Carlton DP, McIntyre TM, Zimmerman GA, Prescott SM. Molecular cloning of human prostaglandin endoperoxide synthase type II and demonstration of expression in response to cytokines. J Biol Chem 1993;268:9049–54.[Abstract/Free Full Text]
  4. DuBois RN, Awad J, Morrow J, Roberts LJ, Bishop PR. Regulation of eicosanoid production and mitogenesis in rat intestinal epithelial cells by transforming growth factor-{alpha} and phorbol ester. J Clin Invest 1994;93:493–8.
  5. Inoue H, Yokoyama C, Hara S, Tone Y, Tanabe T. Transcriptional regulation of human prostaglandin-endoperoxide synthase-2 gene by lipopolysaccharide and phorbol ester in vascular endothelial cells. Involvement of both nuclear factor for interleukin-6 expression site and cAMP response element. J Biol Chem 1995;270:24965–71.[Abstract/Free Full Text]
  6. Subbaramaiah K, Telang N, Ramonetti JT, et al. Transcription of cyclooxygenase-2 is enhanced in transformed mammary epithelial cells. Cancer Res 1996;56:4424–9.[Abstract/Free Full Text]
  7. Subbaramaiah K, Dannenberg AJ. Cyclooxygenase 2: a molecular target for cancer prevention and treatment. Trends Pharmacol Sci 2003;24:96–102.[CrossRef][Medline]
  8. Eberhart CE, Coffey RJ, Radhika A, Giardiello FM, Ferrenbach S, DuBois RN. Up-regulation of cyclooxygenase 2 gene expression in human colorectal adenomas and adenocarcinomas. Gastroenterology 1994;107:1183–8.[Medline]
  9. Ristimaki A, Honkanen N, Jankala H, Sipponen P, Harkonen M. Expression of cyclooxygenase-2 in human gastric carcinoma. Cancer Res 1997;57:1276–80.[Abstract/Free Full Text]
  10. Parrett ML, Harris RE, Joarder FS, Ross MS, Clausen KP, Robertson FM. Cyclooxygenase-2 expression in human breast cancer. Int J Oncol 1997;10:503–7.
  11. Chan G, Boyle JO, Yang EK, et al. Cyclooxygenase-2 expression is up-regulated in squamous cell carcinoma of the head and neck. Cancer Res 1999;59:991–4.[Abstract/Free Full Text]
  12. Tucker ON, Dannenberg AJ, Yang EK, et al. Cyclooxygenase-2 expression is up-regulated in human pancreatic cancer. Cancer Res 1999;59:987–90.[Abstract/Free Full Text]
  13. Kulkarni S, Rader JS, Zhang F, et al. Cyclooxygenase-2 is overexpressed in human cervical cancer. Clin Cancer Res 2001;7:429–34.[Abstract/Free Full Text]
  14. Huang M, Stolina M, Sharma S, et al. Non-small cell lung cancer cyclooxygenase-2-dependent regulation of cytokine balance in lymphocytes and macrophages: up-regulation of interleukin 10 and down-regulation of interleukin 12 production. Cancer Res 1998;58:1208–16.[Abstract/Free Full Text]
  15. Wolff H, Saukkonen K, Anttila S, Karjalainen A, Vainio H, Ristimaki A. Expression of cyclooxygenase-2 in human lung carcinoma. Cancer Res 1998;58:4997–5001.[Abstract/Free Full Text]
  16. Achiwa H, Yatabe Y, Hida T, et al. Prognostic significance of elevated cyclooxygenase 2 expression in primary, resected lung adenocarcinomas. Clin Cancer Res 1999;5:1001–5.[Abstract/Free Full Text]
  17. Soslow RA, Dannenberg AJ, Rush D, et al. COX-2 is expressed in human pulmonary, colonic, and mammary tumors. Cancer 2000;89:2637–45.[CrossRef][Medline]
  18. Khuri FR, Wu H, Lee JJ, et al. Cyclooxygenase-2 overexpression is a marker of poor prognosis in stage I non-small cell lung cancer. Clin Cancer Res 2001;7:861–7.[Abstract/Free Full Text]
  19. Hasturk S, Kemp B, Kalapurakal SK, et al. Expression of cyclooxygenase-1 and cyclooxygenase-2 in bronchial epithelium and nonsmall cell lung carcinoma. Cancer 2002;94:1023–31.[CrossRef][Medline]
  20. Sheng H, Shao J, Washington MK, DuBois RN. Prostaglandin E2 increases growth and motility of colorectal carcinoma cells. J Biol Chem 2001;276:18075–81.[Abstract/Free Full Text]
  21. Ben-Av P, Crofford LJ, Wilder RL, Hla T. Induction of vascular endothelial growth factor expression in synovial fibroblasts by prostaglandin E and interleukin-1; a potential mechanism for inflammatory angiogenesis. FEBS Lett 1995;372:83–7.[CrossRef][Medline]
  22. Tsujii M, Kawano S, Tsuji S, Sawaoka H, Hori M, DuBois RN. Cyclooxygenase regulates angiogenesis induced by colon cancer cells. Cell 1998;93:705–16.[CrossRef][Medline]
  23. Masferrer JL, Leahy KM, Koki AT, et al. Antiangiogenic and antitumor activities of cyclooxygenase-2 inhibitors. Cancer Res 2000;60:1306–11.[Abstract/Free Full Text]
  24. Tsujii M, DuBois RN. Alterations in cellular adhesion and apoptosis in epithelial cells overexpressing prostaglandin endoperoxide synthase-2. Cell 1995;83:493–501.[CrossRef][Medline]
  25. Goodwin JS, Ceuppens J. Regulation of immune response by prostaglandins. J Clin Immunol 1983;3:295–315.[CrossRef][Medline]
  26. Sharma S, Stolina M, Yang SC, et al. Tumor cyclooxygenase-2-dependent suppression of dendritic cell function. Clin Cancer Res 2003;9:961–8.[Abstract/Free Full Text]
  27. Tiano HF, Loftin CD, Akunda J, et al. Deficiency of either cyclooxygenase (COX)-1 or COX-2 alters epidermal differentiation and reduces mouse skin tumorigenesis. Cancer Res 2002;62:3395–401.[Abstract/Free Full Text]
  28. Chulada PC, Thompson MB, Mahler JF, et al. Genetic disruption of Ptgs-1, as well as of Ptgs-2, reduces intestinal tumorigenesis in Min mice. Cancer Res 2000;60:4705–8.[Abstract/Free Full Text]
  29. Williams CS, Tsujii M, Reese J, Dey SK, DuBois RN. Host cyclooxygenase-2 modulates carcinoma growth. J Clin Invest 2000;105:1589–94.[Medline]
  30. Sheng H, Shao J, Kirkland SC, et al. Inhibition of human colon cancer cell growth by selective inhibition of cyclooxygenase-2. J Clin Invest 1997;99:2254–9.[Medline]
  31. Zweifel BS, Davis TW, Ornberg RL, Masferrer JL. Direct evidence for a role of cyclooxygenase-2-derived prostaglandin E2 in human head and neck xenograft tumors. Cancer Res 2002;62:6706–11.[Abstract/Free Full Text]
  32. Sawaoka H, Kawano S, Tsuji S, et al. Cyclooxygenase-2 inhibitors suppress the growth of gastric cancer xenografts via induction of apoptosis in nude mice. Am J Physiol 1998;274:G1061–7.
  33. Liu XH, Kirschenbaum A, Yao S, Lee R, Holland JF, Levine AC. Inhibition of cyclooxygenase-2 suppresses angiogenesis and the growth of prostate cancer in vivo. J Urol 2000;164:820–5.[CrossRef][Medline]
  34. Yao M, Kargman S, Lam EC, et al. Inhibition of cyclooxygenase-2 by rofecoxib attenuates the growth and metastatic potential of colorectal carcinoma in mice. Cancer Res 2003;63:586–92.[Abstract/Free Full Text]
  35. Subbaramaiah K, Hart JC, Norton L, Dannenberg AJ. Microtubule-interfering agents stimulate the transcription of cyclooxygenase-2. Evidence for involvement of ERK1/2 AND p38 mitogen-activated protein kinase pathways. J Biol Chem 2000;275:14838–45.[Abstract/Free Full Text]
  36. Hida T, Kozaki K, Ito H, et al. Significant growth inhibition of human lung cancer cells both in vitro and in vivo by the combined use of a selective cyclooxygenase 2 inhibitor, JTE-522, and conventional anticancer agents. Clin Cancer Res 2002;8:2443–7.[Abstract/Free Full Text]
  37. Altorki NK, Keresztes RS, Port JL, et al. Celecoxib, a selective cyclo-oxygenase-2 inhibitor, enhances the response to preoperative paclitaxel and carboplatin in early-stage non-small-cell lung cancer. J Clin Oncol 2003;21:2645–50.[Abstract/Free Full Text]
  38. Lowry OH, Rosebrough NJ, Farr AL, Randall RJ. Protein measurement with the Folin phenol reagent. J Biol Chem 1951;193:265–75.[Free Full Text]
  39. Golijanin D, Tan JY, Kazior A, et al. Cyclooxygenase-2 and microsomal prostaglandin E synthase-1 are overexpressed in squamous cell carcinoma of the penis. Clin Cancer Res 2004;10:1024–31.[Abstract/Free Full Text]
  40. Dannenberg AJ, Subbaramaiah K. Targeting cyclooxygenase-2 in human neoplasia: rationale and promise. Cancer Cell 2003;4:431–6.[CrossRef][Medline]
  41. Bennett A, Carroll MA, Stamford IF, Whimster WF, Williams F. Prostaglandins and human lung carcinomas. Br J Cancer 1982;46:888–93.[Medline]
  42. Rigas B, Goldman IS, Levine L. Altered eicosanoid levels in human colon cancer. J Lab Clin Med 1993;122:518–23.[Medline]
  43. Lupulescu A. Prostaglandins, their inhibitors and cancer. Prostaglandins Leukot Essent Fatty Acids 1996;54:83–94.[CrossRef][Medline]
  44. Subbaramaiah K, Norton L, Gerald W, Dannenberg AJ. Cyclooxygenase-2 is overexpressed in HER-2/neu-positive breast cancer. J Biol Chem 2002;277:18649–57.[Abstract/Free Full Text]
  45. Subbaramaiah K, Altorki N, Chung WJ, Mestre JR, Sampat A, Dannenberg AJ. Inhibition of cyclooxygenase-2 gene expression by p53. J Biol Chem 1999;274:10911–5.[Abstract/Free Full Text]
  46. Shigemasa K, Tian X, Gu L, Shiroyama Y, Nagai N, Ohama K. Expression of cyclooxygenase-2 and its relationship to p53 accumulation in ovarian adenocarcinomas. Int J Oncol 2003;22:99–105.[Medline]
  47. Leung WK, To KF, Ng YP, et al. Association between cyclo-oxygenase-2 overexpression and missense p53 mutations in gastric cancer. Br J Cancer 2001;84:335–9.[CrossRef][Medline]
  48. Steinbach G, Lynch PM, Phillips RKS, et al. The effect of celecoxib, a cyclooxygenase-2 inhibitor, in familial adenomatous polyposis. N Engl J Med 2000;342:1946–52.[Abstract/Free Full Text]
  49. Murphey LJ, Williams MK, Sanchez, et al. Quantification of the major urinary metabolite of PGE2 by a liquid chromatographic/mass spectrometric assay: determination of cyclooxygenase-specific PGE2 synthesis in healthy humans and those with lung cancer. Anal Biochem 2004;334:266–75.[CrossRef][Medline]
  50. Dixon DA, Tolley ND, King PH, et al. Altered expression of the mRNA stability factor HuR promotes cyclooxygenase-2 expression in colon cancer cells. J Clin Invest 2001;108:1657–65.[CrossRef][Medline]
  51. Sengupta S, Jang BC, Wu MT, Paik JH, Furneaux H, Hla T. The RNA-binding protein HuR regulates the expression of cyclooxygenase-2. J Biol Chem 2003;278:25227–33.[Abstract/Free Full Text]
  52. Subbaramaiah K, Marmo TP, Dixon DA, Dannenberg AJ. Regulation of cyclooxygenase-2 mRNA stability by taxanes. J Biol Chem 2003;278:37637–47.[Abstract/Free Full Text]
  53. Dohadwala M, Batra RK, Luo J, et al. Autocrine/paracrine prostaglandin E2 production by non-small cell lung cancer cells regulates matrix metalloproteinase-2 and CD44 in cyclooxygenase-2-dependent invasion. J Biol Chem 2002;277:30828–33.
  54. Tsujii M, Kawano S, DuBois RN. Cyclooxygenase-2 expression in human colon cancer cells increases metastatic potential. Proc Natl Acad Sci U S A 1997;94:3336–40.[Abstract/Free Full Text]



This article has been cited by other articles:


Home page
 Clin. Cancer Res.Home page
M. J. Fidler, A. Argiris, J. D. Patel, D. H. Johnson, A. Sandler, V. M. Villaflor, J. Coon IV, L. Buckingham, K. Kaiser, S. Basu, et al.
The Potential Predictive Value of Cyclooxygenase-2 Expression and Increased Risk of Gastrointestinal Hemorrhage in Advanced Non-Small Cell Lung Cancer Patients Treated with Erlotinib and Celecoxib
Clin. Cancer Res., April 1, 2008; 14(7): 2088 - 2094.
[Abstract] [Full Text] [PDF]

Home page
 JCOHome page
M. J. Edelman, D. Watson, X. Wang, C. Morrison, R. A. Kratzke, S. Jewell, L. Hodgson, A. M. Mauer, A. Gajra, G. A. Masters, et al.
Eicosanoid Modulation in Advanced Lung Cancer: Cyclooxygenase-2 Expression Is a Positive Predictive Factor for Celecoxib + Chemotherapy--Cancer and Leukemia Group B Trial 30203
J. Clin. Oncol., February 20, 2008; 26(6): 848 - 855.
[Abstract] [Full Text] [PDF]

Home page
 Proc. Natl. Acad. Sci. USAHome page
F. Hohla, A. V. Schally, C. A. Kanashiro, S. Buchholz, B. Baker, C. Kannadka, A. Moder, E. Aigner, C. Datz, and G. Halmos
Growth inhibition of non-small-cell lung carcinoma by BN/GRP antagonist is linked with suppression of K-Ras, COX-2, and pAkt
PNAS, November 20, 2007; 104(47): 18671 - 18676.
[Abstract] [Full Text] [PDF]

Home page
 Proc. Natl. Acad. Sci. USAHome page
F. Hohla, A. V. Schally, K. Szepeshazi, J. L. Varga, S. Buchholz, F. Koster, E. Heinrich, G. Halmos, F. G. Rick, C. Kannadka, et al.
Synergistic inhibition of growth of lung carcinomas by antagonists of growth hormone-releasing hormone in combination with docetaxel
PNAS, September 26, 2006; 103(39): 14513 - 14518.
[Abstract] [Full Text] [PDF]

Home page
 Clin. Cancer Res.Home page
N. D. Gross, J. O. Boyle, J. D. Morrow, M. K. Williams, C. S. Moskowitz, K. Subbaramaiah, A. J. Dannenberg, and A. J. Duffield-Lillico
Levels of Prostaglandin E Metabolite, the Major Urinary Metabolite of Prostaglandin E2, Are Increased in Smokers
Clin. Cancer Res., August 15, 2005; 11(16): 6087 - 6093.
[Abstract] [Full Text] [PDF]

This Article
Right arrow Abstract Freely available
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow reprints & permissions
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Altorki, N. K.
Right arrow Articles by Dannenberg, A. J.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Altorki, N. K.
Right arrow Articles by Dannenberg, A. J.

HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Cancer Research Clinical Cancer Research
Cancer Epidemiology Biomarkers & Prevention Molecular Cancer Therapeutics
Molecular Cancer Research Cancer Prevention Research
Cancer Prevention Journals Portal Cancer Reviews Online
Annual Meeting Education Book Meeting Abstracts Online