Over-expression of c-Myc oncoprotein in oral squamous cell carcinoma

Abstract

Oral neoplasm constitutes a predominant class of cancer that is encountered in South India. This is in large part due to the elevated risk of oncogenesis as a result of the habit of chewing of quids containing betel leaves, areca nut and smokeless tobacco. An array of molecular events are induced during the transformation of the buccal epithelium, among them the over-expression of oncogene products plays a key role. The c-Myc protein, a regulator of a number of key cellular signalling pathways, plays a pivotal role in a number of malignancies. The present study was undertaken to evaluate expression of the c-Myc protein in tumours of the oral cavity from the South Indian population, predominantly oral squamous cell carcinoma (OSCC). The c-Myc protein was over-expressed in 80% of the cases studied. Taking into account the pivotal role demonstrated for c-Myc in tumourigenesis, our observations suggest a key role for Myc oncoprotein in the genesis of OSCC as well as its potential as a therapeutic target in this population.

<p>c-MYC expression in T (III/IV) stage oral squamous cell carcinoma (OSCC) patients</p>

“…C-myc or myc gene was the first to be discovered in this family and is persistently expressed in many different types of cancer, including head and neck squamous cell carcinoma (HNSCC). A number of studies of the molecular mechanisms underlying oncogenesis have shown the emergence of c-Myc expression as a key event, and it is frequently overexpressed in oral cancers as a consequence of gene amplification 4 . C-myc overexpression is responsible for poor tumor prognosis 5 – 8 as well as the self-renewal of tumor stem cells 9 – 12 .…”

Multiclass cancer classification in fresh frozen and formalin-fixed paraffin-embedded tissue by DigiWest multiplex protein analysis

“…Cytokeratin 5 is commonly used as an immunohistochemical marker for squamous cell carcinomas [48]. However, although c-Myc is often expressed in those tumor types, it is not known to be a specific marker for squamous cell carcinomas and has been detected in other tumor types before [49][50][51][52]. The expression of these proteins might not only be useful for diagnostic purposes but could further insight into the tumor's biology and indicate potential therapeutic targets.…”