Table 4

Immunohistochemical analysis in tumors after 11, 18, and 30 days of therapy with C225 and gemcitabine

TherapyVEGFa expression Average (SD)IL-8a expression Average (SD)MVDb Median (range)% apoptotic EC/Total ECc Median (range)
Control
11 days172 (28)170 (28)37 (30–54)0 (0–12)
18 days220 (26)191 (17)73 (53–90)0 (0–5)
30 days151 (20)202 (32)56 (24–180)0 (0–6)
Gemcitabine
11 days162 (21)d168 (21)d38 (31–64)d0 (0–15)d
18 days150 (21)d210 (35)d69 (51–72)d0 (0–5)d
30 days165 (33)d204 (48)d78 (60–89)d10 (7–26)e
C225
11 days97 (13)e100 (13)f27 (15–34)e19 (0–40)e
18 days98 (13)e94 (14)f16 (14–44)f69 (60–81)f
30 days110 (2)e113 (20)f19 (16–22)e63 (60–67)f
C225+ gemcitabine
11 days109 (9)e110 (9)e22 (20–40)e21 (0–43)e
18 days107 (12)e109 (6)e14 (11–18)f62 (27–67)f
30 days114 (29)e111 (32)e9 (4–22)e68 (61–100)f
  • a VEGF and IL-8 cytoplasmic staining was evaluated by computer-assisted image analysis using 10 microscopic fields/tumor section at ×200 (0.033 mm2) and is expressed as the ratio of tumor expression to normal pancreatic epithelium expression multiplied by 100.

  • b The number of CD31-positive vessels was evaluated in 10 microscopic fields per tumor section at ×100 (0.159 mm2) using the Optimas 6.0 computer-assisted image analysis software.

  • c The percentage of TUNEL-positive endothelial cells was determined in 10 microscopic fields/tumor section at ×400 (0.011 mm2) by evaluating the ratio between the number of TUNEL-positive endothelial cells/field and the total number of endothelial cells/field.

  • d No significant difference compared with the control at the same time point.

  • e P < 0.05 compared with the control at the same time point.

  • f P < 0.002 compared with the control at the same time point.