84868

HAVCR2

T-cell immunoglobulin and mucin domain-con-taining protein-3 (TIM-3), a negative regulator of antitumor immune response, has been demonstrated to be involved in the onset and progression of several types of malignancies. The present study aimed to determine whether and how TIM3 plays such a role in esophageal squamous cell carcinoma (ESCC). TIM-3 expression was analyzed by immunohistochemistry and realtime fluorescence quantitative PCR (qRTPCR) in ESCC and matched adjacent normal tissues. Functional experiments in vitro were performed to elucidate the effect of TIM3 knockdown on the proliferation, apoptosis, migration, invasion and epithelial-mesenchymal transition (EMT) in Eca109 and TE1 cell lines. Our data revealed that TIM3 expression was significantly elevated at both the mRNA and protein levels in ESCC tissues compared with the levels in the matched adjacent normal tissues (both P<0.001). TIM3 expression was significantly associated with lymph node metastasis (P=0.008), tumornodemetastasis (TNM) stage (P=0.042) and depth of tumor invasion (P=0.042). In addition, we observed a strong correlation between high TIM3 expression and a worse overall survival of ESCC patients (P=0.001). Functional study demonstrated that TIM3 knockdown markedly inhibited proliferation, migration and invasion of ESCC cell lines without affecting apoptosis. In addition, TIM3 depletion was associated with downregulation of matrix metalloproteinase (MMP)-9 and upregulation of tissue inhibitor of metalloproteinase (TIMP)-1, and with reversion of EMT, as reflected by higher levels of the epithelial marker Ecadherin and lower levels of the mesenchymal markers Ncadherin and vimentin. Further study found that TIM3 depletion suppressed the signaling pathway involving pAkt, pGSK3beta and Snail. Taken together, these results suggest that TIM3 is a novel therapeutic target and prognostic biomarker for ESCC and promotes metastasis of ESCC by inducing EMT via, at least partially, the Akt/GSK-3beta/Snail signaling pathway.

The aim of this study was to investigate the expression of T-cell immunoglobulin mucin domain molecule-3 (Tim-3) in osteosarcoma tissues, and analyze its effect on cell proliferation and metastasis in an osteosarcoma cell line. Tim-3 mRNA and protein expression in osteosarcoma tissue was detected by reverse transcriptase-polymerase chain reaction and immunohistochemistry, respectively. Additionally, the cell viability, apoptosis rate, and invasive ability of the osteosarcoma cell line MG-63 were tested using the methyl thiazolyl tetrazolium assay, Annexin V-propidium iodide flow cytometry, and a Transwell assay, respectively, following Tim-3 interference using small interfering RNA (siRNA). We also analyzed the expression of Snail, E-cadherin, vimentin, and nuclear factor (NF)-kB in the cells by western blot. We observed that Tim-3 mRNA and protein was significantly overexpressed in osteosarcoma tissues, compared to the adjacent normal tissue (P < 0.01). Moreover, MG-63 cells transfected with the Tim-3 siRNA presented lower cell viability, a greater number of apoptotic cells, and decreased invasive ability (P < 0.01), compared to control cells. Additionally, we observed a decrease in Snail and vimentin expression, an increase in the E-cadherin level, and an increase in NF-kB p65 phosphorylation (P < 0.01) in Tim-3 siRNA-transfected MG-63 cells. Based on these results, we concluded that Tim-3 is highly expressed in osteosarcoma tissue. Moreover, we speculated that interfering in Tim-3 expression could significantly suppress osteosarcoma cell (MG-63) proliferation and metastasis via the NF-kB/Snail signaling pathway and epithelial-mesenchymal transition.