
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
Molecular Oncology, Markers, Clinical Correlates |
Departments of Thoracic and Cardiovascular Surgery [M. C., K. O., M. T., H. S., I. Y.] and Pathology [I-Y. K., T. Y.], Mie University School of Medicine, Tsu, Mie, Japan 514-8507
| ABSTRACT |
|---|
|
|
|---|
Experimental Design: In 63 stage-1 NSCLC patients, TN-C protein was analyzed by Western blotting, and the activity of matrix metalloproteinase (MMP)-2 was examined by gelatin zymography in 23 stage-1 NSCLC patients.
Results: Degradation of TN-C was detected in 12 of 63 patients. TN-C degradation was detected in 9 of 17 patients (52.9%) that showed local and distant cancer recurrences. In short, in 9 of 12 patients (75%) showing TN-C degradation, lung cancer recurrence was recognized. The actual frequency of free-from-recurrence at 4 years was 28.1% in patients with tumors showing TN-C degradation, and actual frequency of free-from-recurrence at 4 years and 10 years was 82.1% and 76.6% in patients without TN-C degradation (P < 0.001). In 23 stage-1 NSCLC patients, in tumors with or without degraded TN-C, the mean ratio of tumor:normal-tissue of activated MMP-2 was 3.5 ± 0.4 or 1.54 ± 0.4, respectively. Significantly increased activity of MMP-2 was recognized in tumors showing TN-C degradation (P < 0.001).
Conclusions: These results suggest that TN-C degradation is a reliable marker for recurrence potential of stage-1 NSCLC and that MMP-2 may be a protease breaking down TN-C in lung cancer.
| INTRODUCTION |
|---|
|
|
|---|
80%; the remaining (20%) patients dying of recurrence of lung cancer (1, 2, 3)
. In these patients, it is considered that cancer cells have already metastasized via the blood or lymph streams before operation. If there is a reliable marker that can predict the recurrence in early staged cancer, these patients may receive aggressive chemotherapy that may result in an improvement of survival rate. TN-C (4) 2 is a component of the ECM that has been shown to be involved in tissue interactions during fetal development and oncogenesis. It is a hexomeric glycoprotein consisting of different monomer variants generated by alternative splicing (5 , 6) , in the range of 190250 kDa of molecular sizes. Expression of a high molecular weight variant of TN-C has been suggested to be of significance for tumor progression in cancers (7) . This variant is known to be easily broken down into the fragments by MMPs (8) . We have reported recently that degraded fragments of TN-C are frequently found in lung tumors with metastasis to lymph nodes (9) . In the present study we hypothesized that degraded fragments of TN-C may be potential prognostic indicator of cancer recurrence after surgical treatment.
Therefore, to assess whether TN-C may be an indicator of cancer recurrence and patient prognosis, we examined the relation of TN-C degradation with clinical characteristics in 63 cases with NSCLC at stage 1 without lymph node metastasis. Furthermore, we investigated an association of TN-C degradation with activity of MMPs, especially MMP-2.
| MATERIALS AND METHODS |
|---|
|
|
|---|
|
Tumor and nontumor (normal) tissues of the resected lung were obtained during open thoracotomy, immediately frozen in liquid nitrogen, and stored at -80°C until use.
Western Blotting.
TN-C protein in lung tumors and normal lung tissues were extracted using the method of Kusagawa et al. (9)
. Briefly, the urea extracts (100 µg of protein/lane) were subjected to electrophoresis in 6% SDS-PAGE, as described by Laemmli (11)
. Western blotting was carried out using the Amersham enhanced chemiluminescence system. Rat monoclonal antibody against human TN-C (RCB1) was used at 1.3 µg/ml, and horseradish peroxidase-conjugated secondary antibody (Santa Cruz Biotechnology, Santa Cruz, CA) was used at a 1:2500 dilution. The blots were exposed to X-ray film (Eastman Kodak Co., Rochester, NY) for different intervals (30 s to 2 min) and exposure within the linear range of resolution of the X-ray film were chosen.
Gelatin Zymography.
The gelatinolytic activity was analyzed according to a method described previously (12)
. Briefly, resected tissues were homogenized in sample buffer (10 µl buffer/mg tissue) containing 10 mM Tris/HCl (pH6.8), 20% glycerin, 2% SDS, and 0.1% bromphenol blue. The homogenates were clarified by centrifugation and then separated by electrophoresis on 10% polyacrylamide gel containing 0.1% SDS and 1 mg/ml gelatin as a substrate. Thereafter, gels were washed in the reaction buffer [50 mM Tris-HCl (pH 7.6), 0.15 M NaCl, 10 mM CaCl2, and 0.02% NaN3] containing 2.5% Triton X-100 for 1 h to remove SDS. The gels were then incubated for 24 h at 37°C in the reaction buffer and stained with 0.1% Coomassie Brilliant Blue R250. The location of gelatinolytic activity was detectable as a clear band in the background of uniform staining. Pro- and activated MMP-2 (gelatinase A) bands were detected at 66 and 62 kDa, respectively. The ratio of activated MMP-2 to total MMP-2 activities (62 kDa/66 kDa + 62 kDa) was calculated from their gelatinolytic activities measured by computer-assisted image analysis according to the method of Davies et al. (13)
. We then determined the T:N ratio of the active form of MMP-2 by comparing the percentage of the active form in tumor tissue with that in normal tissue in each case.
Follow-up.
Patients were followed at 3-month intervals after operation. Follow-up evaluation included blood examination and chest roentgenogram at 3-month intervals, and chest computed tomography at 6-month intervals. The follow-up periods have ranged from 4 to 131 months, and the median follow-up period was 62 months.
Statistics.
The association between other different variables was analyzed by the X2 test.
The duration of the free-from-recurrence period was measured from the date of operation until the first evidence of recurrence from primary NSCLC or the last date of follows-up for patients who remained alive and with no recurrence. Survival was calculated from the date of operation until death or the date of the last follow-up. The free-from-recurrence period and survival were analyzed according to the Kaplan-Meier method, and differences in the their distribution were evaluated by the log-rank test. Cox proportional hazards models were applied for univariate analysis. A P < 0.05 was defined as being statistically significant.
| RESULTS |
|---|
|
|
|---|
|
|
|
|
|
|
|
| DISCUSSION |
|---|
|
|
|---|
250 and 190 kDa. These variants are generated by alternative splicing of TN-C RNAs. The larger variant was predominantly found in cancers of breast, prostate, and colon (7
, 17
, 18)
. We also reported that preferential expression of the high molecular weight variant is observed in lung cancer tissues (9)
. In regard to the biological activity of the alternative spliced domain of TN-C, previous in vitro studies show down-regulation of focal adhesion in cultured cells (19)
and stimulation of cell migration in corneal epithelial cells (20)
. Using recombinant fragments of human TN-C, the alternative spliced domain was found to bind to annexin-II on human endothelial cells and to promote cell migration (21)
. These findings suggested that the large TN-C molecules could enhance detachment of cells from the stroma and cell motility.
MMPs are believed to be the main physiologically relevant mediators of matrix degradation (22, 23, 24)
. Siri et al. (8)
have demonstrated that a large TN-C variant can be cleaved into three major fragments of
170, 65, and 16 kDa by MMP-7 and into two major fragments of 190 and 120 kDa by MMP-2. Our results demonstrated that the major degraded TN-C fragments are
120 and 80 kDa in lung cancer tissues. In addition, a recent study has reported that overexpression of MMP-2 indicates unfavorable outcome in early stage NSCLC (25)
. Therefore, we assessed the MMP-2 activity in early stage lung cancer. By gelatin zymography we found that MMP-2 activity in lung cancers is significantly higher than those in normal lung counterparts. This result is consistent with previous reports (26
, 27)
. Furthermore, our results also showed that in patients with TN-C degraded fragments, activated MMP-2 T:N ratio is significantly higher than in those without TN-C-degraded fragments. These results suggest that elevated MMP-2 activity might cleave TN-C into small molecules more efficiently. Although high-level expression of MMP-7 (matrilysin) protein and the mRNA was detected in some lung cancer tissues (28
, 29)
, we could not detect any MMP-7 activity in lung cancer by casein zymography method (data not shown). The expression of MMP-9 (gelatinase B) was also detected in lung cancer tissues. However, there is no relationship between the levels of MMP-9 and TN-C degradation.
Clinicopathological studies have demonstrated the relationship between TN-C expression and metastasis (30 , 31) . Proteolytically digested TN-C can be also found in colon cancer (32) , and degraded TN-C molecules were observed in lung cancer cases with lymph node metastasis at a high frequency (9) . Furthermore, the present study demonstrates a significantly higher recurrence rate in early staged lung cancer patients with TN-C degradation than in those without TN-C degradation. The amount of degraded fragments of TN-C is considered to be related to MMP activities reflecting dynamic remodeling of cancer tissues. However, it is not clear whether TN-C degraded fragments are simply products of ECM degradation or whether the fragments per se have biological activities enhancing cancer invasion and metastasis.
In conclusion, in this study we analyzed the pattern of TN-C expression and its relation to clinic outcome in early staged lung cancer patients. Our data showed that significantly higher recurrence incidence is recognized in patients with TN-C degradation. These results suggest that TN-C degradation could be used as a prognostic indicator for recurrence potential of early stage lung cancer, and that active adjuvant therapy and careful follow-up was necessitated in the patients with TN-C degradation. In addition, we found that significantly higher activities of MMP-2 were detected in patients with TN-C degradation. These results suggest that MMP-2 may be a protease degrading TN-C in lung cancer. Additional in vitro studies necessitate elucidating the relationship between MMP-2 and TN-C in lung cancer.
| ACKNOWLEDGMENTS |
|---|
| FOOTNOTES |
|---|
1 To whom requests for reprints should be addressed, at Department of Thoracic and Cardiovascular Surgery, Mie University School of Medicine, 2-174 Edobashi, Tsu, Mie 514-8507, Japan. Phone: 81-592-32-1111; Fax: 81-592-31-2845; E-mail: K-onoda{at}clin.medic.mie-u.ac.jp ![]()
2 The abbreviations used are: TN-C, tenascin-C; ECM, extracellular matrix; MMP, matrix metalloproteinase; NSCLC, non-small cell lung cancer; T:N, tumor:normal tissue. ![]()
Received 9/ 7/01; revised 1/17/02; accepted 1/28/02.
| REFERENCES |
|---|
|
|
|---|
This article has been cited by other articles:
![]() |
Y. Sawada, K. Onoda, K. Imanaka-Yoshida, J. Maruyama, K. Yamamoto, T. Yoshida, and H. Shimpo Tenascin-C synthesized in both donor grafts and recipients accelerates artery graft stenosis Cardiovasc Res, June 1, 2007; 74(3): 366 - 376. [Abstract] [Full Text] [PDF] |
||||
![]() |
G. Akabani, D. A. Reardon, R. E. Coleman, T. Z. Wong, S. D. Metzler, J. E. Bowsher, D. P. Barboriak, J. M. Provenzale, K. L. Greer, D. DeLong, et al. Dosimetry and Radiographic Analysis of 131I-Labeled Anti-Tenascin 81C6 Murine Monoclonal Antibody in Newly Diagnosed Patients with Malignant Gliomas: A Phase II Study J. Nucl. Med., June 1, 2005; 46(6): 1042 - 1051. [Abstract] [Full Text] [PDF] |
||||
![]() |
C. Bouvet, L.-A. Gilbert, D. Girardot, D. deBlois, and P. Moreau Different Involvement of Extracellular Matrix Components in Small and Large Arteries During Chronic NO Synthase Inhibition Hypertension, March 1, 2005; 45(3): 432 - 437. [Abstract] [Full Text] [PDF] |
||||
![]() |
V. B. Wreesmann, E. M. Sieczka, N. D. Socci, M. Hezel, T. J. Belbin, G. Childs, S. G. Patel, K. N. Patel, G. Tallini, M. Prystowsky, et al. Genome-Wide Profiling of Papillary Thyroid Cancer Identifies MUC1 as an Independent Prognostic Marker Cancer Res., June 1, 2004; 64(11): 3780 - 3789. [Abstract] [Full Text] [PDF] |
||||
![]() |
M.-R. Pan and W.-C. Hung Nonsteroidal Anti-inflammatory Drugs Inhibit Matrix Metalloproteinase-2 via Suppression of the ERK/Sp1-mediated Transcription J. Biol. Chem., August 30, 2002; 277(36): 32775 - 32780. [Abstract] [Full Text] [PDF] |
||||
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| 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 |