Expression of Leishmania major LmSTI1 in Yeast Pichia Pastoris

Background: Leishmania major LmSTI1 is a conserved protein among different species of leishmania, and expressed in both amastigote and promastigote forms of L. major life cycle. It has previously been expressed in bacterial systems.Materials and Methods: To express LmSTI1 in the methylotrophic yeast         Pichia pastoris (P. pastoris), the shuttle vector pPICZA containing gene lmsti1 was constructed under the control of the AOX1 promoter. The recombinant vector was electro-transformed into P. pastoris, and induced by 0.5% methanol in the buffered medium. The expression of the LmSTI1 protein was visualized in the total soluble protein of P. pastoris by 12% SDS-PAGE, and further confirmed by Western blotting with L.major-infected mouse sera and HRP-conjugated goat anti-mouse IgG as the first and secondary antibodies, respectively.Results: The expression level was 0.2% of total soluble proteins.Conclusion: It might be possible to use this formulation as a whole yeast candidate vaccine against cutaneous leishmanization

Evaluation of p53, PTEN and β-catenin Immunoexpressions in Primary Ovarian Epithelial Tumors

Background: Ovarian cancer comprises a heterogeneous group of neoplasms. The prognosis cannot be predicted by histopathologic examination alone. The aim of this study is to evaluate p53, PTEN, and β-catenin expressions in primary ovarian carcinomas in an attempt to find a possible relationship with morphologic parameters and clinical findings. Methods: The study included 100 epithelial ovarian tumors (borderline and carcinomas) from affiliated hospitals of Shiraz university of medical sciences during 2007-2013. Immunohistochemical staining for p53, PTEN, and β-catenin was performed on 65 serous, 18 mucinous, 10 endometrioid, 5 clear cell, and 2 mixed tumors. Results: p53 expression pattern in serous carcinoma significantly differed from endometrioid carcinomas. Strong positivity (2+) in >50% of the tumor cells favored serous carcinoma. PTEN expression significantly differed in mucinous and serous carcinomas as well as in endometrioid carcinoma and borderline endometrioid tumor. There was significantly decreased β-catenin expression in the carcinomas compared with borderline tumors. In all of the different subtypes of ovarian carcinomas, we observed a significant association with decreased β-catenin expression to tumor grade as well as in serous carcinomas with increased nuclear grade, mitosis, and tumor grade. There was no significant relation between expressions of p53, PTEN, and β-catenin in epithelial ovarian tumors to FIGO staging, response to chemotherapy, serum CA- 125 marker, and tumor recurrence. Conclusion: p53 and PTEN are helpful in differentiation of some epithelial ovarian tumor subtypes. In serous carcinomas, diminished expression of β-catenin is associated with higher tumor and nuclear grade. This expression is significantly different in borderline and carcinomas