The tumor control mechanism of galectin-3 in urological cancer invasion and metastasis

点击翻译按钮获取中文摘要

Galectin-3 is a member of the family of β-galactoside binding mammalian lectins that is expressed at elevated levels in a variety of neoplastic cell types and has been implicated in tumor invasion and metastatic process, and apoptosis, though there are still some conflicting data regarding a certain type of tumors. To date, in urological cancer field, few experimental and clinical evidences have been reported regarding galectin-3 and cancer invasion in terms of apoptosis. We studied the expression of galecin-3 in renal cell carcinoma cell lines and human renal cell carcinoma tissues by RT-PCR and western blot analysis, and investigated the clinical significance and the possibility as a tumor marker. The expression of galectin-3 was identified in every renal cell carcinoma cell line we employed and was significantly higher in human renal cell carcinoma tissues than normal kidney tissues (418.6±137.3 vs 66.7±13.5, p=0.019). Especially in the case with metastasis, the expression ratio was … More significantly high (p=0.035), which suggested that ratio could become prognostic factor of metastasis. Similarly, in metastasis cases, the expressions of the genes associated with angiogenesis or TRAIL-induced apoptosis were elevated in proportion to that of galectin-3.We observed that RT4 cells had very low level of constitutively active Akt and were sensitive to TRAIL, while UM-UC-3 and T24 cells had higher level of constitutively active Alt and were resistant to TRAIL. The expression level of active Akt was higher in galectin-overexpressed cells than that in wild type cells, though total expression level of Akt were similar between these cells, implicating the relation of galectin-3 in TRAIL resistance. 50% Galectin-3 knocked down cells demonstrated the decrease of active Akt expression to the same extent as that down-regulated by PI3K inhibitors.Considering application to clinical field in future, some biological modulation will be required to find the possibility of galectin-3 as apoptosis inducing factor in urological cancers. Less