Expression and clinical significance of mTOR/p70S6K signaling pathway in breast carcinoma

Abstract

Objective To investigate the expression of TOR(mammalian target of rapamycinm)/p70S6K(70 kDa ribosomal protein S6 kinase) signaling pathway in human breast carcinoma. Methods From January 2013 to January 2016, 40 cases of breast carcinom tissues,40 cases of paracancerous tissues,32 cases of normal breast tissues were selected in Binzhou Central Hospital Affiliated to Binzhou Medical College.RT-PCR and Immunohistochemistry were employed to determine the expression of mTOR/p70S6K signaling pathway in cancerous and paracancerous tissuess of 40 cases and normal healthy tissues of 32 cases. The relationship between expression of the genes mRNA in breast carcinom tissues and related parameters was analyzed. Results The expression level of mTOR was markedly higher in the breast carcinoma tissues (0.611±0.098) than in the paracancerous tissues (0.419±0.101) or normal breast tissues (0.381±0.043) .The expression of p70S6K mRNA was also higher in the breast carcinoma tissues(0.625±0.109) than in the paracancerous tissues(0.471±0.129) or normal breast tissues(0.441±0.130), with a significant difference among groups (P<0.05). There was a positive correlation between mTOR mRNA and p70S6K mRNA expressions in breast carcinom tissues (γ=0.491, P=0.019). The expression of mTOR/p70S6K signaling pathway in the breast carcinom tissues was significantly correlated with the pathological grading, lymph node metastasis, but not with the diameter, and age. Conclusions The mTOR/P70S6K signaling pathway is specifically activated in breast carcinom tissues. The mTOR/p70S6K signaling pathway might play an important role in the pathogenesis of breast carcinom. Key words: Breast carcinoma; Mammalian target of rapamycinm(mTOR); 70 kDa ribosomal protein S6 kinase(P70S6K); RT-PCR; Immunohistochemistry