Abstract 2767: Expression of miR-1252 and its target PRR4 gene in laryngeal carcinoma

Abstract

Abstract Head and neck squamous cell carcinoma (HNSCC) is the sixth most frequent cancer worldwide and includes neoplasias of the paranasal sinuses, the oral cavity, the trachea, the pharynx and the larynx. The most important risk factors are tobacco use, alcohol consumption and infection with human papillomavirus (HPV). Besides the exogenous risk factors, genetic factors may play a key role in the development of the HNSCC. Cancer of the larynx accounts for 25% of all head and neck malignancies. The PRR4 (Prolin Rich Protein 4) gene is localized on human chromosome 12p13 and encodes a protein which is secreted from the acinar cells of the lacrimal gland, the submandibular gland, the parotis and the sublingual glands. Recent studies have demonstrated that PRR4 may play an important role as an antimicrobial protein to protect the ocular surface and the oral cavity. Additionally, it has been shown that PRR4 is highly expressed in the human submucosal glands. microRNAs are small non-coding RNAs which regulate gene expression at the post-transcriptional level. They bind to their target RNA with their seed sequence complementary to the 3’UTR region. This interaction results in either up- or down-regulation of the target messenger RNA. To understand the role of the PRR4 gene in laryngeal carcinogenesis, we investigated its mRNA expression levels in laryngeal tumor tissue and adjacent non-cancerous tissue samples from 90 patients by quantitative real-time PCR. As a complementary region between the seed sequence of miR-1252 and 3’UTR region of PRR4 gene exists, we also analyzed whether miR-1252 binds to this region and regulates the expression of PRR4. We found that PRR4 gene expression was decreased in 65 (72.2%) and increased in 24 (26.7%) of 90 tumor tissues when compared to normal tissue. Statistically significant downregulation of the PRR4 mRNA was observed in laryngeal tumors (p<0.001). No significant correlation was found between PRR4 gene expression and clinicopathological parameters including age, sex, stage, histological grade and tumor location (p>0.05). We also analyzed miR-1252 expression levels in a subset of tumor samples. miR-1252 upregulation was observed only in 24% of tumor tissues compared to non-cancerous tissue. The miR-1252 level was same in the 62.5% of the remaining samples. We did not observe any correlation between the PRR4 and miR-1252 expression levels. Our results indicate that the PRR4 gene may have an impact in the progression of laryngeal carcinoma. Citation Format: NUR BUYRU, SEDA EKIZOGLU, JALAL GULIYEV, EMIN KARAMAN, TURGUT ULUTIN. Expression of miR-1252 and its target PRR4 gene in laryngeal carcinoma. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 2767.