Heat shock protein 70 is involved in malignant behaviors and chemosensitivities to cisplatin in cervical squamous cell carcinoma cells.

AIM: Heat shock protein 70 (HSP70) was previously found to be highly expressed in cervical squamous cell carcinoma (SCC) tissues compared with normal tissues by proteomic analyses. The present study investigated the roles of HSP70 in malignant behaviors and chemosensitivity to cisplatin in cervical SCC cells in vitro. METHODS: Effects of HSP70 knockdown on activities of cell migration, cell invasion and cell proliferation, cell cycle status, and apoptosis were examined using siRNA in two human cervical cancer cells (SiHa and SKG II). Furthermore, the effect of HSP70 knockdown on the apoptotic effect by cisplatin was examined. RESULTS: HSP70 knockdown significantly suppressed activities of cell migration, cell invasion and cell proliferation. The cell cycle was arrested at the S- and G2/M-phases with the increase in apoptosis by HSP70 knockdown. Although cisplatin had no apoptotic effect in the control cell, it showed a dose-dependent apoptotic effect in the HSP70 knockdown cells in SiHa. In SKG II, 5 µg/mL of cisplatin induced apoptosis, and the apoptotic effect by cisplatin was enhanced by HSP70 knockdown. CONCLUSION: It was suggested that HSP70 played functional roles in the progression of uterine cervical SCC, and HSP70 knockdown enhanced chemosensitivities to cisplatin in cervical SCC cells.

Decreased carbonyl reductase 1 expression promotes malignant behaviours by induction of epithelial mesenchymal transition and its clinical significance.

Human carbonyl reductase 1 (CBR1) is an enzyme that catalyse the reduction of many compounds by using NADPH-dependent oxydoreductase activity. Although CBR1 is known to regulate the tumour progression, the molecular mechanisms of CBR1 in cancer progression and the clinical significance of CBR1 status remain unclear. Here, we investigated the molecular mechanisms by which CBR1 affects cancer cell behaviour in vitro and the clinical significance of CBR1 using immunohistochemical analyses in endometrial cancer. Here, the role of CBR1 in cancer cell invasion and metastasis, and its molecular mechanisms were investigated by transfection of sense and antisense CBR1 cDNAs into a human endometrial adenocarcinoma cell line. The relationship between CBR1 expression analysed by immunohistochemistry and prognosis such as progression free survival (PFS) and overall survival (OS) was examined in endometrial cancer tissues from FIGO stage I-IV (n=109). Suppression of CBR1 by antisense CBR1 cDNA increased cancer cell invasion, and suppressed E-cadherin expression and capacity for cellular aggregation. In contrast, over-expression of CBR1 by sense CBR1 cDNA increased E-cadherin expression and capacity for cellular aggregation, and suppressed cancer cell invasion. The expression of transcriptional suppressors of E-cadherin, Snail and ZEB1, were increased by CBR1 suppression, but suppressed by CBR1 over-expression. Immunohistochemical analyses showed that decreased CBR1 expression is significantly related with poor PFS and OS compared with strong CBR1 expression. In multivariate analyses, decreased CBR1 expression was an independent prognostic factor for PFS and OS. CBR1 regulates cancer cell invasion in endometrial adenocarcinomas by regulating the epithelial mesenchymal transition. A decreased CBR1 expression can be a useful marker of an unfavourable clinical outcome in patients with endometrial cancer.

Suppression of carbonyl reductase expression enhances malignant behaviour in uterine cervical squamous cell carcinoma: carbonyl reductase predicts prognosis and lymph node metastasis.

Carbonyl reductase (CR) is an NADPH-dependent, mostly monomeric, cytosolic enzyme with broad substrate specificity for carbonyl compounds. CR appears to be involved in the regulation of tumour progression. However, molecular mechanisms of CR in tumour progression and clinical significance of CR status remain unclear in human uterine squamous cell carcinoma (SCC). Here, we investigated the clinical significance of CR using immunohistochemical analyses of human uterine cervical SCC tissues and how CR affects cancer cell behaviour in vitro. Paraffin sections from uterine cervical SCC tissues, FIGO stage Ib1-IIb (n = 67) were immunostained with anti-CR antibodies. Overall survival (OS) and progression-free survival (PFS) were analyzed by the Kaplan-Meier method. Sense and antisense CR cDNAs were transfected into a human uterine SCC cell line (SiHa) to investigate the role of CR in cancer cell invasion and metastasis. Immunohistochemical analyses showed that reduced CR expression patterns in primary cancer lesions were closely associated with a high incidence of pelvic lymph node metastasis, poor OS, and poor PFS. In an in vitro experiment, suppression of CR increased cancer cell invasion, secretion of MMP-2, -9 and cyclooxygenase-2 (COX-2) expression and decreased E-cadherin expression. On the other hand, over-expression of CR increased E-cadherin expression and decreased MMP-2, -9 secretion and COX-2 expression. The reduced CR expression pattern, as measured by immunohistochemistry, can be a useful predictor of lymph node metastasis and poor prognosis in patients with uterine SCC. This clinical result is supported by the in vitro data which show that suppression of CR expression promotes cancer cell invasion with decreased E-cadherin expression and increased MMP-2, -9 secretion.