| Human tissue kallikrein 6 (KLK6) is a serine protease that is over-expressed in ovarian cancer. In this study, we aimed to delineate the mechanisms underpinning this phenomenon. We first confirmed the up-regulation of KLK6 in ovarian tumor cytosols and its value as an unfavorable prognostic biomarker. KLK6 mRNA expression was then assessed and observed to be concordant with KLK6 protein expression, implicating a role for transcriptional regulation. We examined the relative abundance of two KLK6 transcripts. Samples of various KLK6 levels showed the same differential expression pattern. Genomic mutation screening of KLK6 in ovarian tumor samples identified two linked single nucleotide polymorphisms in the 5'-untranslated region, neither correlated with KLK6 expression. Ovarian cell lines were treated with five steroid hormones, no significant effects on KLK6 expression were observed. We conclude that KLK6 is transcriptionally up-regulated in ovarian cancer but not through alternative transcript expression, genetic aberration or steroid hormone induction. |
