High expression of transform growth factor beta 1 in gastric cancer confers worse outcome: results of a cohort study on 184 patients.

BACKGROUND/AIMS: Transform growth factors beta (TGFbeta) plays different roles at different stages of tumor development. TGFbeta1 is one isoform of TGFbeta, with complex secretion mechanism and bidirectional functions. This study was to investigate TGFbeta1 expression and its clinical significance in different clinicopathological subgroups of gastric cancer (GC) patients.

METHODOLOGY: Tumor and peritumoral tissues from 184 GC patients were constructed into three tumor tissue microarrays. The expression of TGFbeta1 was analyzed by immunohistochemistry methods.

RESULTS: TGFbeta1 was mainly expressed in the cytoplasm and membrane of GC cells. Low TGFbeta1 expression was observed in 82 (44.6%) tumor and 28 (68.3%) peritumoral tissues, and high expression was observed in 102 (55.4%) tumor and 13 (31.7%) peritumoral tissues. TGFbeta1 expression was significantly higher in tumor than peritumoral tissues (chi2 = 7.554, P = 0.006). The high expression of TGFbeta1 was related to worse overall survival (OS) (P = 0.040). TGFbeta1 expression was higher in the old and intestinal type GC than in the young (P = 0.017) and in diffuse type GC (P = 0.015), respectively. Patients with high TGFbeta1 expression had a worse survival in young people, female, diffuse type GC, poor differentiation, and lymph nodes metastasis. Multivariate Cox proportional hazards analysis showed that age, pathological grading, serosal invasion and TGFbeta1 expression were independent risk factors.

CONCLUSIONS: High TGFbeta1 expression may indicate poor prognosis of GC patients and warrant more active treatment against TGFbeta1.