Effects of NBS1 in MRN complex on gallbladder carcinoma cells

Abstract

Objective To study the expression of MRE11-RAD50-NBS1 complex in normal gallbladder tissues, simple cholecystitis, calculous cholecystitis and gallbladder carcinoma . Methods The expression of MRN complex in different gallbladder lesion tissues were detected by immunohistochemistry. Western blot, Methyl thiazolyl tetrazolium(MTT)assay and flow cytometry were used to detect the influence of apoptosis and proliferation induced by NBS1. Results The differences between the expression of MRE11, RAD50 and different gallbladder lesion tissues were not statistically significant ( respectively χ2 =2.724, 1.697, all P>0.05). The expression of NBS1 in GBC tissues[15.3%(9/59)]was prominently lower than that in the normal gallbladder tissues[84.7%(50/59)], simple cholecystitis[87.8%(36/41)], calculous cholecystitis[61.2%(30/49)](χ2=87.388, P<0.01) . The Western blot results reveal that NBS1 can mediate apoptosis by up-regulate Bax and down-regulate Bcl-2. The MTT assay results showed that the relative absorbance of treatment and control group after 24, 48, 72 h were[(1.120±0.006) vs. (1.350±0.009), (1.600±0.004) vs. (1.99±0.01), (1.83±0.01) vs. (2.260±0.003)(F=7.659, P<0.01). The apoptosis rate in treatment group(17.23%± 0.56%)was higher than that in the control group (4.13% ±0.67%) (t=9.133, P<0.01). Conclusion NBS1 is closely related to gallbladder carcinoma. NBS1 can inhibit the proliferation and promote apoptosis of GBC-SD cells. Key words: Gallbladder neoplasms; Cell proliferation; Apoptosis