Intestinal transformation results in transforming growth factor-beta-dependent alteration in tumor cell-cell matrix interactions

Biologic determinants of tumor recurrence in stage II colon cancer: validation study of the 12-gene recurrence score in cancer and leukemia group B (CALGB) 9581

PURPOSE

A greater understanding of the biology of tumor recurrence should improve adjuvant treatment decision making. We conducted a validation study of the 12-gene recurrence score (RS), a quantitative assay integrating stromal response and cell cycle gene expression, in tumor specimens from patients enrolled onto Cancer and Leukemia Group B (CALGB) 9581.

PATIENTS AND METHODS

CALGB 9581 randomly assigned 1,713 patients with stage II colon cancer to treatment with edrecolomab or observation and found no survival difference. The analysis reported here included all patients with available tissue and recurrence (n = 162) and a random (approximately 1:3) selection of nonrecurring patients. RS was assessed in 690 formalin-fixed paraffin-embedded tumor samples with quantitative reverse transcriptase polymerase chain reaction by using prespecified genes and a previously validated algorithm. Association of RS and recurrence was analyzed by weighted Cox proportional hazards regression.

RESULTS

Continuous RS was significantly associated with risk of recurrence (P = .013) as was mismatch repair (MMR) gene deficiency (P = .044). In multivariate analyses, RS was the strongest predictor of recurrence (P = .004), independent of T stage, MMR, number of nodes examined, grade, and lymphovascular invasion. In T3 MMR-intact (MMR-I) patients, prespecified low and high RS groups had average 5-year recurrence risks of 13% (95% CI, 10% to 16%) and 21% (95% CI, 16% to 26%), respectively.

CONCLUSION

The 12-gene RS predicts recurrence in stage II colon cancer in CALGB 9581. This is consistent with the importance of stromal response and cell cycle gene expression in colon tumor recurrence. RS appears to be most discerning for patients with T3 MMR-I tumors, although markers such as grade and lymphovascular invasion did not add value in this subset of patients.

Transforming growth factor beta 1 and metalloproteinase-9 overexpression in colorectal cancer (CC) and adenoma

BACKGROUND AND AIMS

Although the role of transforming growth factor beta (TGFbeta) 1 and metalloproteinase-9 (MMP-9) is well documented in colorectal cancer (CC), there is a little evidence supporting its role in early carcinogenesis. The aim of the study was to determine the pattern of immunohistochemical expression of TGFbeta1, MMP-9, and Ki-67 in CC and adenomatous polyps.

PATIENT/METHODS

The study group comprised 50 patients with colorectal polyps and 33 patients with CC. Endoscopically removed polyps and CC biopsies had been evaluated with histopatologic examination and immunohistochemistry. The biopsies from 30 healthy objects served as a control group. For all antibodies labeling indices (LI) had been calculated.

RESULTS

Among 62 adenomas, 33 high-grade dysplasia (HGD) and 29 low-grade dysplasia (LGD) had been detected. Mean TGFbeta1, MMP-9, and Ki-67 LI in CC were significantly higher (p < 0.01, 0.01, and 0.01, respectively) than in HGD polyps. Mean TGFbeta1, MMP-9, and Ki-67 LI in HGD polyps were significantly higher than in LGD polyps (p < 0.01, 0.01, and 0.01, respectively). There had been no statistical difference in TGFbeta1, MMP-9, and Ki-67 LI between LGD and the control group (p > 0.05, 0.05, and 0.05, respectively). There was a positive correlation between TGFbeta1 and MMP-9 (r = 0.898), Ki-67 and MMP-9 (r = 0.938), and TGFbeta1 and Ki-67 (r = 0.913). We did not observe any correlation between TGFbeta1, MMP-9, Ki-67 LI and the clinical parameters evaluated.

CONCLUSION

The increased expression of TGFbeta1, MMP-9 observed in colorectal adenomas seems to be related to the grade of dysplasia. We assume that overexpression of TGFbeta1, MMP-9 represent an early event in colorectal carcinogenesis and may possibly have the prognostic value.

Effects of transforming growth factor-beta in the development of inflammatory pseudotumour-like lesions in a murine model

Alterations in transforming growth factor (TGF)-beta signalling have been frequently implicated in human cancer, and an important mechanism underlying its pro-oncogenic nature is suppression of the host antitumour immune response. Considering the immunosuppressive effect of TGF-beta, we asked whether human tumour cells, known to secrete TGF-beta in culture, would survive and grow when implanted into the peritoneal cavity of immunocompetent mice. Therefore, we developed a xenogeneic model where mice were intraperitoneally (i.p.) injected with a TGF-beta-secreting human colorectal adenocarcinoma cell line, LISP-A10. Although animals did not develop macroscopic tumours, the recovery and isolation of human tumour cells was achieved when an inflammatory environment was locally induced by the administration of complete Freund's adjuvant (CFA). This procedure significantly increased TGF-beta concentrations in the peritoneal fluid and was accompanied by impaired activation of the host-specific immune response against LISP-A10 cells. Furthermore, inflammatory lesions resembling human inflammatory pseudotumours (IPTs) were observed on the surface of i.p. organs. These lesions could be induced by either injection of LISP-A10 cells, cells-conditioned medium or recombinant TGF-beta but only after administration of CFA. In addition, host cyclooxygenase-2 and kinin receptors played an important role in the induction of TGF-beta-mediated IPT-like lesions in our experimental model.

Tissue-type plasminogen activator activity in morphologically normal tissues adjacent to gastrointestinal carcinomas is associated with the degree of tumor progression

PURPOSE

To investigate whether the level of plasminogen activator (PA) activity assayed in gastrointestinal carcinomas and the "morphologically normal tissues" adjacent to them is associated with the degree of tumor progression.

METHODS

Tumor and "normal tissues" were obtained from gastrointestinal surgical samples to assess urokinase-type (u-PA) and tissue-type plasminogen activator (t-PA) activities by radial caseinolytic assay and the expression of PA inhibitor-1 (PAI-1) by ELISA. We compared the PA system between the tumor and "normal tissues" and we investigated the existence of correlations between: (a) PA production in the tumor and "normal tissues", (b) different components of the PA system, and (c) PA system and the degree of tumor progression.

RESULTS

(1) Total PA activity, u-PA activity and PAI-1 expression are significantly higher in tumor than in "normal tissues", whereas t-PA activity does not differ between them. (2) Total PA activity mainly correlates with u-PA activity in tumor tissues and similarly with u-PA and t-PA activities in "normal tissues". (3) There is a significant association between t-PA activity in tumor and "normal tissues" and the degree of tumor progression.

CONCLUSIONS

"Morphologically normal tissues" adjacent to carcinomas present abnormal t-PA activity that is associated with the degree of tumor progression. Assaying of this activity could be useful as a predictive parameter.

Celecoxib Inhibits Urokinase-Type Plasminogen Activator (uPA) Production in MDA-MB-231 Breast Cancer Cells

Elevated urokinase-type plasminogen activator (uPA) expression in breast tumors predicts poor survival. We found celecoxib (25 microM) significantly reduced uPA protein and mRNA in MDA-MB-231 breast cancer cells following 72 h of treatment. Celecoxib also inhibited cell viability (12.5 and 25 microM) and induced G2M arrest (25 microM). Therefore, celecoxib therapy for uPA positive breast cancer should be explored.

The role of glial cell line-derived neurotrophic factor (GDNF) and integrins for invasion and metastasis in human pancreatic cancer cells

BACKGROUND AND OBJECTIVES

It is generally accepted that the malignancy of pancreatic cancer is dependent upon the extent of invasion as well as metastasis. However, the factors and mechanisms are incompletely understood. We investigated whether glial cell lined-derived neurotrophic factor (GDNF) enhances the invasive and adhesive behaviors of pancreatic cancer cells by altering of the expression of integrins.

METHODS

The expression of the GDNF receptor in pancreatic cancer cell lines (SW1990 and Capan-2) was confirmed by RT-PCR. Then we determined the expression of integrin subunits and the alteration of their expression by GDNF using flow-cytometric analysis and a cellular enzyme-linked immunosorbent assay (CELISA). Adhesion and invasion assay were performed to investigate whether increased integrin expression affected the interaction between cancer cells and ECM proteins.

RESULTS

The GDNF receptor subunits were expressed in pancreatic cancer cells. GDNF enhanced the expression of some of the integrin subunits and increased their adhesive and invasive abilities. The enhanced expression and associated increase in adhesive and invasive abilities were inhibited by blocking the GDNF receptor or the integrin beta1 subunit.

CONCLUSION

The enhancement of integrin expression by GDNF signaling through the GDNF receptor strongly influences invasion and adhesion to ECM proteins by pancreatic cancer cells.