Krüppel-like factor 5 as potential molecular marker in cervical cancer and the KLF family profile expression

Abstract

Cervical cancer (CC) as other cancer types, presents molecular deregulations, such as the alterations of transcription factors. Krüppel-like factors (KLF) are a family of transcriptional regulators. They are involved in diverse cellular processes, such as proliferation, apoptosis, and angiogenesis among others. Here, we analyzed the expression of all 17 KLF members at messenger RNA (mRNA) level, and protein expression of the two most commonly altered KLF5 and KLF6 in cervical tissues. Fifty-nine cervical tissues ranging from normal tissue to CC were evaluated for KLF1-17 mRNA expression by end-point RT-PCR and KLF5 by qRT-PCR. For KLF5 and KLF6 protein analysis, a tissue microarray was constructed containing the 59 cases and subjected for immunohistochemistry assay and KLF6 IVS1-27G>A single nucleotide polymorphism by direct DNA sequencing. KLF2-16 expressions were present in normal tissue, whereas all 17 were present in Low-Grade Squamous Intraepithelial Lesion, High-Grade-SIL and CC, unrelated to presence of human papillomavirus (HPV). KLF5 mRNA expression gradually increased throughout the subgroups and overexpressed in CC (p=0.01). KLF5 and KLF6 proteins were immunodetected in all samples. For the KLF6 SNP analysis, 80% of the CC population analyzed presented GG genotype and the remaining 20% presented GA genotype (p=0.491). Our present data show that KLFs expression could not be related to HPV presence, at least at transcriptional level, and KLF5 mRNA overexpression could represent a potential molecular marker for CC; KLF6 SNP has no relation to increased risk of CC.