Expression And Prognostic Significance Of CREPT, Ki-67and PCNA In Primary Retroperitoneal Leiomyosarcoma

Background: To investigate the expression and clinical prognostic significance ofCREPT, Ki-67and PCNA in retroperitoneal leiomyosarcoma.Methods:71tissue samples of patients who were diagnosed with primaryretroperitoneal leiomyosarcoma after surgeries were collected from PLA GeneralHospital during1998-2012and another5fresh tissue samples during2013. The proteinlevels of CREPT, Ki-67and PCNA were examined in all retroperitonealleiomyosarcoma samples by immunohistohemical staining. Analysis and comparisonthe expression of CREPT, Ki67and PCNA in five retroperitoneal leiomyosarcoma casesand control samples by western blot.Results: More More than half of the patients were shown positive expression of CREPT,Ki-67and PCNA by immunohistochemical analysis. The expression of CREPT wascorrelated with histological grade（P=0.044）, and PCNA expressional level wascorrelated with the differentiation of tumour cells and histological grade（P<0.001；P=0.009）. In addition, univariate analysis showed that the survival time of64patientswhich were followed up was related to tumour size, histological grade and CREPT，Ki-67，PCNA expressional level（P=0.038；P=0.024；P=0.022；P=0.047；P=0.042）.Multivariate analysis showed that survival time is only associated with histologicalgrade and the expression level of CREPT （P=0.011；P=0.012）. Kaplan–Meieranalysis showed that patients with CREPT negative expression had significantly longeroverall postoperative survival times (median,60.0months) compared to patients withpositive CREPT expression (median,33.0months). CREPT expression is correlationwith distant recurrence in5years after surgery (P=0.004). Western blot analyses showedthat CREPT were more highly expressed in the tumour parts of retroperitonealleiomyosarcoma than normal control tissue of the same patients.Conclusions: CREPT can be used as a prognosis factor for overall survival time anddistant recurrence in primary retroperitoneal leiomyosarcoma. CREPT is suggested to be a potential prognostic marker for primary retroperitoneal leiomyosarcoma.