The Molecular Genetics of MUC16

CA125抗原是一种特性良好的卵巢上皮性癌血清标志物，在临床上用于监测对治疗的反应和这种恶性肿瘤的复发。最近鉴定和克隆了一个编码CA125抗原核心肽的cDNA分子，发现其与一个膜相关粘蛋白家族具有相当的同源性，并将其命名为MUC16。MUC16的克隆和表征为基于分子遗传学的MUC16在卵巢肿瘤中作用的机制评估提供了多种新的机会。该项目的长期目标是验证MUC16在基因的发展和/或维持中起关键作用的假设

The CA125 antigen is a well-characterized serum marker for epithelial ovarian carcinoma and is utilized clinically to monitor response to therapy and recurrence of this malignancy. Recent identification and cloning of a cDNA molecule encoding the core peptide of the CA125 antigen revealed considerable homology to a family of membrane-associated mucins, and the CA125-encoding gene was designated MUC16. The cloning and characterization of MUC16 provides multiple new opportunities for a molecular genetic-based, mechanistic evaluation of the role of this molecule in ovarian neoplasia. The long-term goal of this project is to test the hypothesis that MUC16 plays a critical role in the development and/or maintenance of the malignant phenotype in ovarian carcinoma. This goal will be accomplished through a broad range of experimental approaches designed to gain insight into the function of MUC16 in normal development and cell biology, as well as in the neoplastic transformation of ovarian epithelial cells. The specific aims of this project are to: 1) Annotate the genomic structures and analyze promoters of the MUC16 and Muc16 genes. Exon-intron boundaries, coding regions, untranslated regions and transcription factor binding sites will be characterized physically and functionally. 2) Characterize the function of Muc16 in vivo. Protein expression during embryonic development and in the neonatal and adult mouse and in murine ovarian cancers will be determined, as will the effects of transgenic knockdown of Muc16 in a temporal- and tissue-specific manner when crossed with transgenic mice prone to invasive ovarian carcinoma. 3) Using previously generate data on the regulation of MUC16 expression, correlate implied molecular pathways with promoter structure, and test the hypothesis that CA125 secretion results from post-translational processing of MUC16, exploring the mechanism of this processing. 4) Determine whether a reduction in MUC16 expression in human ovarian carcinoma cells affects the neoplastic phenotype. An RNA interference approach will be used to determine whether reduction of MUC16 mRNA levels in human ovarian carcinoma cells affects cell proliferation, differentiation, anchorage-independent growth or tumorigenicity in vivo. It is anticipated that studies of the function of MUC16 in multiple biological contexts will prove most effective in ultimately elucidating the role of this molecule in ovarian tumorigenesis.