calpastatin and Esophageal-Neoplasms

Surgery is critical in the management of gastro-oesophageal cancer, and the addition of neo-adjuvant chemotherapy has proved to be of benefit. The calpain system has been implicated in tumour progression and response to various anti-cancer therapies, and therefore expression of the system was determined in this tumour type.. Two cohorts of gastro-oesophageal adenocarcinomas were investigated for calpain-1, calpain-2, calpain-9 and calpastatin expression using conventional immunohistochemistry. 88 patients who received neo-adjuvant chemotherapy and 140 patients who received surgery alone were investigated using a tissue microarray approach.. Calpain-1, calpain-2 and calpastatin expression was associated with adverse cancer-specific survival in the neo-adjuvant cohort (P = 0.004, P = 0.001 and P = 0.012 respectively); which remained significant in multivariate analysis (Hazard ratio (HR) = 0.337; 95% confidence interval (CI) = 0.140-0.81; P = 0.015, HR = 0.375; 95% CI = 0.165-0.858; P = 0.020 and HR = 0.481; 95% CI = 0.257-0.900; P = 0.022 respectively). Calpain-1 and calpastatin expression was also associated with adverse cancer specific survival in the primary surgery cohort (P = 0.001 and P = 0.013 respectively); which remained significant in multivariate analysis (HR = 0.309; 95% CI = 0.159-0.601; P = 0.001 and HR = 0.418; 95% CI = 0.205-0.850; P = 0.016 respectively). Calpain-9 expression was not associated with cancer-specific survival in the neo-adjuvant and primary surgery cohorts.. Determining the expression levels of calpain-1, calpain-2 and calpastatin may provide clinically relevant prognostic information for gastro-oesophageal adenocarcinomas; these findings warrant further studies in larger cohorts of patients.

Topics: Adenocarcinoma; Antineoplastic Combined Chemotherapy Protocols; Biomarkers, Tumor; Calcium-Binding Proteins; Calpain; Chemotherapy, Adjuvant; Esophageal Neoplasms; Humans; Kaplan-Meier Estimate; Neoplasm Invasiveness; Neoplasm Staging; Prognosis; Tissue Array Analysis; Treatment Outcome

Chemosensitivity to anticancer drugs was compared between two human esophageal carcinoma cell lines, T.Tn and YES-6 cells. T.Tn cells were more resistant than YES-6 cells to peplomycin (PEP) but not to the other anticancer drugs such as camptothecin, mitomycin C and cytosine arabinoside. Western blot analysis showed higher expression levels of m-calpain and activated mu-calpain in T.Tn cells than in YES-6 cells. On the other hand, YES-6 cells showed a high expression level of calpastatin, which is a calpain-specific endogenous inhibitor. To investigate whether calpain activity was involved in the chemosensitivity, T.Tn cells were transfected with calpastatin cDNA in an inducible expression vector. The induction of calpastatin was accompanied by increased chemosensitivity to PEP. The increases in calpastatin levels were followed by serial increases in the expression levels of NF-kappaB p65 and Fas. Since purified m- or mu-calpain degraded NF-kappaB p65 in vitro, it is possible that calpastatin suppressed calpain-mediated degradation of NF-kappaB p65. Fas ligand (Fas-L) protein levels increased after treatment of the parental T.Tn and calpastatin-transfected cells with PEP, suggesting the synergism between calpastatin-induced Fas and PEP-induced Fas-L. These results suggest that calpain/calpastatin expression levels are effective markers for predicting the sensitivity of human esophageal carcinoma cells to PEP.

Topics: Antibiotics, Antineoplastic; Calcium-Binding Proteins; Carcinoma; Cell Line, Tumor; Esophageal Neoplasms; Fas Ligand Protein; fas Receptor; Humans; Peplomycin; Transcription Factor RelA