Expression Change Of XIAP,LC3B And P62 In Breast Cancer Before And After Neoadjuvant Chemotherapy And Their Significance

Background Several studies showed suppression of XIAP and increased autophagic activity in cytotoxic drug induced apoptosis.This experiment aims to investigate the changes of XIAP,LC3 B and p62 expression in breast cancer solid tumors before and after neoadjuvant chemotherapy(NCT)and their significance.Methods The expression of XIAP,LC3 B and p62 was detected by immunohistochemistry in 94 cases of breast carcinoma before and after NCT to observe the changes of XIAP,LC3 B and p62 expression after NCT and analyze their relationship with tumor resistance and the correlation between them.Results1)Breast cancer tissue degenerates in varying degrees after NCT.Invasive cancer component degenerate and die resulting in only residual carcinoma in situ or only a few cancer cells cord-like and nest-like arrangement or even only a single cancer cells in fibrous interstitia.Breast cancer cells undergo morphological changes similar to apoptosis manifested as cell shrinkage,increased eosinophilic cytoplasm,nuclear condensation and enhanced staining.2)The high expression rate of XIAP was 84.0%(79/94)while that of LC3 B and p62 was 39.4%(37/94)and 51.1%(48/94)respectively in 94 cases of breast cancer before NCT.The high expression rate of XIAP was reduced to 35.1%(33/94),and that of LC3 B and p62 was increased to 73.4%(69/94)and 81.9%(77/94)respectively in 94 cases of breast cancer after NCT.The high expression rate of XIAP was significantly decreased while that of LC3 B and p62 was significantly increased after NCT.The difference was statistically significant(P both=0.000).The decreased sample rate for XIAP was 75.5%(71/94)while the increased sample rate for LC3 B and p62 expression was 67.0%(63/94)and 73.4%(69/94)respectively in 94 cases of breast cancer after NCT.3)We discovered that non-therapeutic effect rate of low expression of LC3 B was 20.0%,while the rate of high group was 44.9% through comparison of expression of XIAP,LC3 B and p62 after NCT with the therapeutic effects.The difference was statistically significant(P=0.028)while the other two protein,XIAP and p62 had no significant.4)Non-therapeutic effect rate of upregulation group of LC3 B was 50.8%,while the rate of the other group was 12.9% through comparison of expression changes of XIAP,LC3 B and p62 after NCT with the therapeutic effects.The differences was statistically significant(P=0.000)while the other two protein,XIAP and p62 had no significant.5)The change of XIAP expression was significantly negatively correlated with the change of LC3 B and p62(P=0.000 and 0.003)by Spearman rank correlation test.Conclusion:1)Downregulation of XIAP and upregulation of LC3 B and p62 expression coexist in breast cancer after NCT.2)NCT can induce autophagy enhancement that may play a role in breast cancer resistance to NCT.3)XIAP downregulation is closely related to autophagy enhancement after NCT in breast cancer.