Differential transmission of the molecular signature of RBSP3, LIMD1 and CDC25A in basal/ parabasal versus spinous of normal epithelium during head and neck tumorigenesis: A mechanistic study.

Shreya Sarkar,Supratim Ghosh,Neyaz Alam,Chinmay Kumar Panda,Kabita Chatterjee,Syam Sundar Mandal,Susanta Roychoudhury,Javier S Castresana

doi:10.1371/journal.pone.0195937

Abstract

Head and neck squamous cell carcinoma (HNSCC) is a global disease and mortality burden, necessitating the elucidation of its molecular progression for effective disease management. The study aims to understand the molecular profile of three candidate cell cycle regulatory genes, RBSP3, LIMD1 and CDC25A in the basal/ parabasal versus spinous layer of normal oral epithelium and during head and neck tumorigenesis. Immunohistochemical expression and promoter methylation was used to determine the molecular signature in normal oral epithelium. The mechanism of alteration transmission of this profile during tumorigenesis was then explored through additional deletion and mutation in HPV/ tobacco etiological groups, followed byclinico-pathological correlation. In basal/parabasal layer, the molecular signature of the genes was low protein expression/ high promoter methylation of RBSP3, high expression/ low methylation of LIMD1 and high expression of CDC25A. Dysplastic epithelium maintained the signature of RBSP3 through high methylation/ additional deletion with loss of the signatures of LIMD1 and CDC25A via deletion/ additional methylation. Similarly, maintenance and / or loss of signature in invasive tumors was by recurrent deletion/ methylation. Thus, differential patterns of alteration of the genes might be pre-requisite for the development of dysplastic and invasive lesions. Etiological factors played a key role in promoting genetic alterations and determining prognosis. Tobacco negative HNSCC patients had significantly lower alterations of LIMD1 and CDC25A, along with better survival among tobacco negative/ HPV positive patients. Our data suggests the necessity for perturbation of normal molecular profile of RBSP3, LIMD1 and CDC25A in conjunction with etiological factors for head and neck tumorigenesis, implying their diagnostic and prognostic significance.

Highlights

An omnipresent acrimony, Head and Neck Squamous Cell Carcinoma (HNSCC),comprising of oral, nasopharyngeal and laryngeal cancers represents> 95% of all head and neck (H&N) malignancies [1]
Which signature, the basal/ parabasal, or that of the spinous layer in normal epithelium gets transmitted during progressive development of HNSCC, or how it alters in tumorigenesis, along with the role of etiological factors, especially tobacco and Human Papilloma Virus (HPV) is yet to be understood
Several studies indicate the importance of stem cells in oral basal/parabasal epithelium for maintaining tissue integrity [3]

Summary

Introduction

Head and Neck Squamous Cell Carcinoma (HNSCC),comprising of oral, nasopharyngeal and laryngeal cancers represents> 95% of all head and neck (H&N) malignancies [1]. It presents sixth highest global prevalence, constituting30–40% of total cancer incidents in the Indian subcontinent, with tobacco, betel quid, alcohol and Human Papilloma Virus (HPV) as risk factors [2].Evidence indicate the pre-requisition of non- random aberrations (epigenetic/ genetic) in the normal basal stem-like layer for epithelial tumorigenesis including HNSCC [3, 4], the molecular events involved are elusive. Analysis of the status of RBSP3, LIMD1 and CDC25A in basal/parabasal versus spinous of normal oral epithelium, followed by their alterations (methylation/ deletion/ mutation/ expression) are essential to interpret their role during tumorigenesis

Methods

Results

Conclusion