Genetic Polymorphisms in Oral Cancer - Correlation with Clinicopathologic Parameters
Objectives: Altered expression of xenobiotic enzymes such as GSTM1, GSTT1 and CYP1A1 has been reported in some malignant tumors including oral cancer. However, the correlation between these enzymes and clinicopathologic parameters has not been well documented. The aim was to investigate associations between GSTM1, GSTT1 and CYP1A1 polymorphism with age of onset, nodal status, tumor size and disease stage.
Methods: A total of 136 oral cancer patients were included in this study. Peripheral blood was obtained from consented individuals and GSTM1, GSTT1 and CYP1A1 genotypes were determined using PCR and restriction enzyme digestion. Chi-square test was used for comparison of all parameters except for age of onset where the t-test was used.
Results: Positive nodes is associated with high GSTM1 null (55.8%), low GSTT1 null (43.8%) and no difference for CYP1A1 polymorphism (53.3%). Polymorphism of all 3 genes was higher in late stage compared to early stage disease. However, statistically, these observations were not significant. For tumor size of more than 2cm, there was higher percentage of GSTT1 null genotype (96.9%) as compared to those with tumor size of less than 2 cm (p=0.035). Mean age of onset was higher in those with GSTT1 null genotype (62.6±10.3years) compared to lower mean age of onset for those with GSTT1 non-null genotype (57.6±12.5years) and this observation was significant (p=0.031). There was no significant difference between GSTM1 and CYP1A1 polymorphism and age of onset.
Conclusions: This study showed that the GSTT1 null genotype is associated with age of onset and tumor size while no association was seen with nodal status and disease stage. No association was observed between GSTM1 and CYP1A1 polymorphism and all the clinicopathologic parameters studied, suggesting that polymorphism of these genes may not contribute to the aggressive behaviour of oral cancer among Malaysians.
Grant: MOSTI, Malaysia, IRPA RMK8 Project No:06-02-03-0174PR0054/05-05
Division: Southeast Asian Division Meeting
Meeting:2007 Southeast Asian Division Meeting (Bali, Indonesia) Location: Bali, Indonesia
Year: 2007 Final Presentation ID: Abstract Category|Abstract Category(s):Scientific Groups
Authors
Abraham, Mannil Thomas
( Ministry of Health, Putrajaya, N/A, Malaysia
)
Hamid, Sharifah
( Cancer Research Initiatives Foundation (CARIF), Subang Jaya, N/A, Malaysia
)
Mustafa, Wan Mahadzir Wan
( Ministry of Health, Putrajaya, N/A, Malaysia
)
Prepageran, N.
( Oral Cancer Research & Coordinating Centre (OCRCC), Kuala Lumpur, N/A, Malaysia
)
Yuen, Kar Mun
( Ministry of Health, Putrajaya, N/A, Malaysia
)
Samsudin, Abdul Rani
( Oral Cancer Research & Coordinating Centre (OCRCC), Kuala Lumpur, N/A, Malaysia
)
Tay, Keng Kiong
( Ministry of Health, Putrajaya, N/A, Malaysia
)
Jalil, Norma
( Ministry of Health, Putrajaya, N/A, Malaysia
)
Karen Ng, Lee Peng
( Oral Cancer Research & Coordinating Centre (OCRCC), Kuala Lumpur, N/A, Malaysia
)
Ghani, Wan Maria Nabillah
( Oral Cancer Research & Coordinating Centre (OCRCC), Kuala Lumpur, N/A, Malaysia
)
Ismail, Siti Mazlipah
( Oral Cancer Research & Coordinating Centre (OCRCC), Kuala Lumpur, N/A, Malaysia
)
Cheong, Sok Ching
( Cancer Research Initiatives Foundation (CARIF), Subang Jaya, N/A, Malaysia
)
Zain, Rosnah Binti
( Oral Cancer Research & Coordinating Centre (OCRCC), Kuala Lumpur, N/A, Malaysia
)
Razak, Ishak Abdul
( Oral Cancer Research & Coordinating Centre (OCRCC), Kuala Lumpur, N/A, Malaysia
)
Raja Latifah, R. J.
( Oral Cancer Research & Coordinating Centre (OCRCC), Kuala Lumpur, N/A, Malaysia
)
Rahman, Zainal Ariff Abdul
( Oral Cancer Research & Coordinating Centre (OCRCC), Kuala Lumpur, N/A, Malaysia
)