Differential expression of myosin light chain kinase in human epithelial ovarian cancer.
Epithelial ovarian cancer (EOC) is the most lethal gynecologic cancer (1). We performed discovery of genes associated with epithelial ovarian cancer and of the high-grade serous ovarian cancer (HGSC) subtype, using published and public microarray data (2, 3) to compare global gene expression profiles of normal ovary or fallopian tube with that of primary tumors from women diagnosed with epithelial ovarian cancer or HGSC. We identified the gene encoding myosin light chain kinase, MYLK, as among the genes whose expression was most different in epithelial ovarian cancer as compared to the normal fallopian tube. MYLK expression was significantly lower in high-grade serous ovarian tumors relative to normal fallopian tube. MYLK expression correlated with progression-free survival in patients with ovarian cancer. These data indicate that expression of MYLK is perturbed in epithelial ovarian cancers broadly and in ovarian cancers of the HGSC subtype. MYLK may be relevant to pathways underlying ovarian cancer initiation (transformation) or progression.