Molecular Genetics of Oral Cancer


Oral squamous cell carcinoma (OSCC) is the most common epithelial malignancy in the oral cavity and constitutes more than 90% of oral malignancies. OSCC is a complex malignancy where environmental factors, viral infections and genetic alterations most likely interact, and thus give rise to the malignant condition. Epidemiological investigations have shown that heavy tobacco smoking, high alcohol consumption and human papilloma virus infection are the major risk factors for OSCC development. These factors interact with specific genes important for normal cellular development and genetic alterations may finally lead to a malignant phenotype. Genetic mutations accumulated over time are needed for an oral cancer to develop and several molecular genetic changes have been associated with the development of OSCC. The most important genetic alterations associated with the condition are tumour suppressor genes, oncogenes, epigenetic changes, genomic instability, mitochondrial mutations, microRNAs and loss of heterozygosity.

Key Concepts:

  • Oral cancer is caused by extrinsic and/or intrinsic factors.

  • Loss of heterozygosity is an important event in oral carcinogenesis.

  • Mutated p53 is a common event in OSCC.

  • Telomere length is maintained in some OSCC.

  • mtDNA is involved in OSCC.

  • Epigenetic changes seem to be an early event in oral carcinogenesis.

  • miRNA may be aberrant in OSCC.

Keywords: oral cancer; molecular genetics; tumour suppressor gene; epigenetic; loss of heterozygosity; miRNA; microsatellite instability; telomerase; oncogene; mtDNA mutation

Figure 1.

Oral carcinogenesis.



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Further Reading

Ha PK and Califano JA (2006) Promotor methylation and inactivation of tumour‐supressor genes in oral squamous‐cell carcinoma – Review. Lancet Oncology 7: 77–82.

Mithani SK, Mydlarz WK, Grumbine FL, Smith IM and Califano JA (2007) Molecular genetics of premalignant lesions – Review. Oral Diseases 13: 126–133.

van Monsjou HS, Wreesman VB, van den Brekel MWM and Balm AJM (2013) Head and neck squamous cell carcinoma in young patients – Review. Oral Oncology 49: 1097–1102.

Pitiyage G, Tilakaratne WM, Tavassoli M and Warnakulasuriya S (2009) Molecular markers of oral epithelial dysplasia – Review. Journal of Oral Pathology & Medicine 38: 737–752.

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How to Cite close
Sand, Lars(May 2014) Molecular Genetics of Oral Cancer. In: eLS. John Wiley & Sons Ltd, Chichester. [doi: 10.1002/9780470015902.a0025222]