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 (TGF beta) plays different roles at different stages of tumor development. TGF beta 1 is one isoform of TGF beta, with complex secretion-mechanism and bidirectional functions. This study was to investigate TGF beta 1 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 TGF beta 1 was analyzed by immunohistochemistry methods. Results: TGF beta 1 was mainly expressed in the cytoplasm and membrane of GC cells. Low TGF beta 1 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. TGF beta 1 expression was significantly higher in tumor than peritumoral tissues (chi(2) = 7.554, P = 0.006). The high expression of TGF beta 1 was related to worse overall survival (OS) (P = 0.040). TGF beta 1 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 TGF beta 1 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 TGF beta 1 expression were independent risk factors. Conclusions: High TGF beta 1 expression may indicate poor prognosis of GC patients and warrant more active treatment against TGF beta 1.