Common oncogenic mutations are infrequent in oral squamous cell carcinoma of Asian origin

• Published in: PloS one 2013-11, Vol.8 (11), p.e80229-e80229
• Main Authors: Zanaruddin, Sharifah Nurain Syed, Yee, Pei San, Hor, Seen Yii, Kong, Yink Heay, Ghani, Wan Maria Nabillah Wan Abd, Mustafa, Wan Mahadzir Wan, Zain, Rosnah Binti, Prime, Stephen S, Rahman, Zainal Ariff Abd, Cheong, Sok-Ching
• Format: Article
• Language: English
• Subjects: Alcohol use; Analysis; Asian Continental Ancestry Group; Carcinoma, Squamous Cell - genetics; Class I Phosphatidylinositol 3-Kinases; Dental materials; Dentistry; Deoxyribonucleic acid; Diagnostic software; Diagnostic systems; DNA; Exons; Exons - genetics; Female; Gene mutation; Genes; Genetic aspects; Genetic Predisposition to Disease; Habits; Hot spots; Human papillomavirus; Humans; In Vitro Techniques; Kinases; Laboratories; Lung cancer; Male; Maxillofacial surgery; Medical ethics; Medical research; Middle Aged; Mouth Neoplasms - genetics; Mutation; Mutation hot spots; Oral cancer; Oral squamous cell carcinoma; p53 Protein; Patients; Phosphatidylinositol 3-Kinases - genetics; Review boards; Risk; Smoking; Solid tumors; Squamous cell carcinoma; Statistical analysis; Surgery; Survival; Tobacco; Tumor proteins; Tumor Suppressor Protein p53 - genetics; Tumors
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0080229

The frequency of common oncogenic mutations and TP53 was determined in Asian oral squamous cell carcinoma (OSCC). The OncoCarta(™) panel v1.0 assay was used to characterize oncogenic mutations. In addition, exons 4-11 of the TP53 gene were sequenced. Statistical analyses were conducted to identify associations between mutations and selected clinico-pathological characteristics and risk habits. Oncogenic mutations were detected in PIK3CA (5.7%) and HRAS (2.4%). Mutations in TP53 were observed in 27.7% (31/112) of the OSCC specimens. Oncogenic mutations were found more frequently in non-smokers (p = 0.049) and TP53 truncating mutations were more common in patients with no risk habits (p = 0.019). Patients with mutations had worse overall survival compared to those with absence of mutations; and patients who harbored DNA binding domain (DBD) and L2/L3/LSH mutations showed a worse survival probability compared to those patients with wild type TP53. The majority of the oncogenic and TP53 mutations were G:C > A:T and A:T > G:C base transitions, regardless of the different risk habits. Hotspot oncogenic mutations which are frequently present in common solid tumors are exceedingly rare in OSCC. Despite differences in risk habit exposure, the mutation frequency of PIK3CA and HRAS in Asian OSCC were similar to that reported in OSCC among Caucasians, whereas TP53 mutations rates were significantly lower. The lack of actionable hotspot mutations argue strongly for the need to comprehensively characterize gene mutations associated with OSCC for the development of new diagnostic and therapeutic tools.