Abstract:

Objective To investigate the effect of ST6GalⅠ on the apoptosis of renal clear cell carcinoma cells and itspossible mechanism. Methods The expression of ST6GalⅠ and TNFR1 in renal clear cell carcinoma cell lines were detected byqRT-PCR and Western blot. The renal clear cell carcinoma cell lines with different expression of ST6GalⅠ were constructed，and the apoptosis level was detected by flow cytometry，and the correlation between the expression of ST6GalⅠ and TNFR1was analyzed，the expression of TNFR1 in the differentially expressed ST6GalⅠcells were detected by qRT-PCR and Westernblot，and the apoptosis level of A498 and Caki-1 cells that differentially expressed ST6GalⅠand TNFR1 were detected byflow cytometry. Results ST6GalⅠ was highly expressed in 5 renal clear cell carcinoma cell lines（P＜0.05）. The apoptosis

rate of A498 cells increased after ST6Gal Ⅰ was inhibited （P＜0.01），while the apoptosis rate of Caki-1 cells reducedfor the overexpression of ST6GalⅠ（P<0.001）. TNFR1 mRNA and protein were low-expressed in 5 renal clear cell cancer celllines，and negatively correlated with ST6GalⅠmRNA and protein expression（r=-0.9667，-0.9928，all P<0.01）. The expressionof TNFR1 increased when the expression of ST6Gal Ⅰ（P<0.001） was inhibited，while the expression of TNFR1 decreased forthe overexpression of ST6GalⅠ（P<0.001）. The apoptosis rate of A498 cells after inhibition of both ST6GalⅠand TNFR1expression was lower than that of ST6GalⅠalone （P<0.01），and the apoptosis rate of Caki-1 cells after overexpression ofboth ST6GalⅠand TNFR1 was higher than that of ST6GalⅠalone （P<0.01）. Conclusions ST6GalⅠcan inhibit the apoptosis ofrenal clear cell carcinoma cell lines by inhibiting the expression of TNFR1.

Key words: Renal clear cell carcinoma, ST6GalⅠ, TNFR1, Apoptosis