Cancers of the upper aero-digestive and gastrointestinal tract are one of the major causes of mor... more Cancers of the upper aero-digestive and gastrointestinal tract are one of the major causes of mortality around the world. DNA repair genes play a vital role in preventing carcinogenesis by maintaining genomic integrity. Polymor-phisms in the nucleotide sequence of DNA repair genes are often reported to be associated with an increased risk for different cancers. The OGG1 gene encodes the enzyme 8-oxoguanine DNA glycosylase which removes oxidatively damaged bases of DNA. Several studies report that the OGG1 Ser326Cys polymorphism increases the risk for cancers of the upper aero-digestive and gastrointestinal tract. However, other studies provide evidence that such an association does not exist. A meta-analysis to assess the role of OGG1 Ser326Cys polymorphism in the cancers of the upper aero-digestive and gastrointestinal tract was therefore undertaken in order to resolve this ambiguity. Seventeen studies were recruited for this meta-analysis after screening 58 articles with a total of 5533 cases and 6834 controls for which the odds ratio with 95 % confidence interval was calculated. Begg's funnel test and Egger's test were performed for calculating publication bias. Our study reveals an association between OGG1 Ser326Cys polymorphism and cancer susceptibility of the upper aero-digestive and gastrointestinal tract (CG + GG vs CC; odds ratio, OR 1.22; 95 % CI 1.05–1.41; GG vs CG + CC; OR 1.36; 95 % CI 1.09–1.70; GG vs CC; OR 1.46; 95 % CI 1.12–1.92). Subgroup analysis based on cancer types and ethnicity also revealed the association of OGG1 Ser326Cys polymorphism to the risk for upper aero-digestive and gastrointestinal tract cancers among both the Asian and the Caucasian populations. No risk was however observed for smoking habits and OGG1 Ser326Cys polymorphism. In conclusion, OGG1 Ser326Cys polymorphism may be associated with the increased risk for aero-digestive tract and gastro-intestinal cancers in both Asian and Caucasian populations.
A number of different epidemiological studies have measured the association between the risk of d... more A number of different epidemiological studies have measured the association between the risk of different cancers and polymorphism at promoter region of 5′ untranslated region (5′-UTR) of the Ataxia-telangiectasia mutated (ATM) gene. However the results were contentious rather than conclusive. The current study was aimed at evaluating the association between the SNP (rs189037 G>A) and the risk of head and neck cancer and lung cancer by conducting ameta-analysis. A total of 9 case–control studieswere considered for this quantitative analysis. Stats Direct Statistical software (version 2.7.2)was used to evaluate the crude odds ratio (OR) with their 95% confidence interval (CI). The dominant model (GG vs. GA+ AA) showed no heterogeneity and the fixed effects pooled OR was found to be significant (OR = 1.14, 95% CI = 1.05–1.25) at p = 0.003. The pooled OR for fixed effects of heterozygote and homozygote mutant allele (GA vs. AA) model was significant (OR = 1.17, 95% CI = 1.04–1.30, p=0.006) and no heterogeneity was observed for this model. The current meta-analysis manifested that ATM rs189037 G>A genetic polymorphismmay contribute increased risk of head and neck and lung cancer. Moreover, the AA mutant allele was found to be related significantly with the prognosis of lung cancer and head and neck cancer
A number of different epidemiological studies have measured the association between the risk of d... more A number of different epidemiological studies have measured the association between the risk of different cancers and polymorphism at promoter region of 5′ untranslated region (5′-UTR) of the Ataxia-telangiectasia mutated (ATM) gene. However the results were contentious rather than conclusive. The current study was aimed at evaluating the association between the SNP (rs189037 G>A) and the risk of head and neck cancer and lung cancer by conducting ameta-analysis. A total of 9 case–control studieswere considered for this quantitative analysis. Stats Direct Statistical software (version 2.7.2)was used to evaluate the crude odds ratio (OR) with their 95% confidence interval (CI). The dominant model (GG vs. GA+ AA) showed no heterogeneity and the fixed effects pooled OR was found to be significant (OR = 1.14, 95% CI = 1.05–1.25) at p = 0.003. The pooled OR for fixed effects of heterozygote and homozygote mutant allele (GA vs. AA) model was significant (OR = 1.17, 95% CI =1.04–1.30, p=0.006) and no heterogeneity was observed for this model. The current meta-analysis manifested that ATM rs189037 G>A genetic polymorphismmay contribute increased risk of head and neck and lung cancer. Moreover, the AA mutant allele was found to be related significantly with the prognosis of lung cancer and head and neck cancer.
Background: Polymorphisms in the MDM2 309 (T>G) and TP53 72 (G>C) genes are reported to increase ... more Background: Polymorphisms in the MDM2 309 (T>G) and TP53 72 (G>C) genes are reported to increase the susceptibility to head and neck cancer (HNC) in various populations. The risk for HNC is also strongly associated with etiologic habits such as smoking, alcohol consumption and/or chewing of betel quid (BQ). In a case-control study, we investigated the significance of the above polymorphisms alone, and upon interaction with one another as well as with various etiologic habits in determining HNC risk in a Northeast Indian population. Materials and Methods: Genotyping at 309 MDM2 and 72 TP53 in 122 HNC patients and 86 cancer free healthy controls was performed by PCR using allele specific primers, and the results were confirmed by DNA sequencing. Results: Individuals with the GG mutant allele of MDM2 showed a higher risk for HNC in comparison to those with the TT wild type allele (OR=1.9, 95%CI: 1.1-3.3) (p=0.022). The risk was further increased in females by ~4-fold (OR=4.6, 95% CI: 1.1-19.4) (P=0.04). TP53 polymorphism did not contribute to HNC risk alone; however, interaction between the TP53 GC and MDM2 GG genotypes resulted in significant risk (OR=4.9, 95% CI: 0.2-105.1) (p=0.04). Smokers, BQ- chewers and alcohol consumers showed statistically significant and dosedependent increase in HNC risk, irrespective of the MDM2 genotype. Conclusions: MDM2 genotype could serve as an important predictive biomarker for HNC risk in the population of Northeast India.
In the present study, we investigated the effect of
the DNA repair gene polymorphisms XPD Asp312... more In the present study, we investigated the effect of
the DNA repair gene polymorphisms XPD Asp312Asn
(G>A), APE1 Asp148Glu (T>G), and MUTYH Tyr165Cys
(G>A) on the risk for head and neck cancer (HNC) in association
with tobacco use in a population of Northeast India. The
study subjects comprised of 80 HNC patients and 92 healthy
controls. Genotyping was performed using amplification refractory
mutation system—PCR (ARMS-PCR) for XPD
Asp312Asn (G>A) and PCR using confronting two-pair
primers (PCR-CTPP) for APE1 Asp148Glu (T>G) and
MUTYH Tyr165Cys (G>A). The XPD Asp/Asn genotype increased
the risk for HNC by 2-fold (odds ratio, OR=2.072;
95 % CI, 1.025–4.190; p<0.05). Interaction between APE1
Asp/Asp and XPD Asp/Asn as well as MUTYH Tyr/Tyr and
XPD Asp/Asn genotypes further increased the risk by 2.9
(OR=2.97; 95 % CI, 1.16–7.61; p<0.05) and 2.3 (OR=
2.37; 95 % CI, 1.11–5.10; p<0.05) folds, respectively. The
risk was further increased in heavy smokers with the XPD
Asp/Asn genotype and heavy tobacco chewers with XPD
Asn/Asn genotype by 7.7-fold (OR=7.749; 95 % CI, 2.53–
23.70; p<0.05) and 10-fold (OR=10; 95 % CI, 1.26–79.13;p<0.05), respectively. We thus conclude that the XPD
Asp312Asn and APE1 Asp148Glu polymorphisms increase
the risk for HNC in association with smoking and/or tobacco
chewing in the population under study.
A study was carried out to assess the hepatoprotective and hypoglycemic activity of the leaf extr... more A study was carried out to assess the hepatoprotective and hypoglycemic activity of the leaf extracts of Phyllanthus acidus in Wister albino rats against the widely used drugs i.e. Silymarin for hepatoprotective activity and Glibenclamide for hypoglycaemic activity. Phyllanthus acidus leaves were collected from different localities of Agartala, Tripura, India. Aqueous extract of P. acidus was analyzed in carbon tetra chloride induced jaundice rats to evaluate the hepatoprotective activity. Hepatic enzymes like transaminase (AST), alanine transaminase (ALT), alkaline phosphatase (ALP), and total bilirubin were estimated from the blood sample of rats on 8th day after treatment through semi auto analyzer. Alcoholic extract of P. acidus leaf was used to check hypoglycaemic activity in rats. Blood glucose level was estimated through glucose oxidase method on 0-2 hours after overnight fasting. The present study revealed that the aqueous extract of the leaf of P. acidus is as effective as the standard drug Silymarin in decreasing the hepatic markers in rats suffering from jaundice. It also revealed that the alcohol extract of P. acidus leaf possesses hypoglycemic activity at a dose of 200mg/Kg which is as effective as Glibenclamide, a commonly used drug for hypoglycaemic activity. The study revealed that the leaves of Phyllanthus acidus have both hepatoprotective and hypoglycemic activity on dose dependent manner just like commercial drugs available in the market. Further research is needed to understand the mode of action of the leaf extract of P. acidus in protecting liver and reducing blood sugar in rats at molecular level.
Cancers of the upper aero-digestive and gastrointestinal tract are one of the major causes of mor... more Cancers of the upper aero-digestive and gastrointestinal tract are one of the major causes of mortality around the world. DNA repair genes play a vital role in preventing carcinogenesis by maintaining genomic integrity. Polymor-phisms in the nucleotide sequence of DNA repair genes are often reported to be associated with an increased risk for different cancers. The OGG1 gene encodes the enzyme 8-oxoguanine DNA glycosylase which removes oxidatively damaged bases of DNA. Several studies report that the OGG1 Ser326Cys polymorphism increases the risk for cancers of the upper aero-digestive and gastrointestinal tract. However, other studies provide evidence that such an association does not exist. A meta-analysis to assess the role of OGG1 Ser326Cys polymorphism in the cancers of the upper aero-digestive and gastrointestinal tract was therefore undertaken in order to resolve this ambiguity. Seventeen studies were recruited for this meta-analysis after screening 58 articles with a total of 5533 cases and 6834 controls for which the odds ratio with 95 % confidence interval was calculated. Begg's funnel test and Egger's test were performed for calculating publication bias. Our study reveals an association between OGG1 Ser326Cys polymorphism and cancer susceptibility of the upper aero-digestive and gastrointestinal tract (CG + GG vs CC; odds ratio, OR 1.22; 95 % CI 1.05–1.41; GG vs CG + CC; OR 1.36; 95 % CI 1.09–1.70; GG vs CC; OR 1.46; 95 % CI 1.12–1.92). Subgroup analysis based on cancer types and ethnicity also revealed the association of OGG1 Ser326Cys polymorphism to the risk for upper aero-digestive and gastrointestinal tract cancers among both the Asian and the Caucasian populations. No risk was however observed for smoking habits and OGG1 Ser326Cys polymorphism. In conclusion, OGG1 Ser326Cys polymorphism may be associated with the increased risk for aero-digestive tract and gastro-intestinal cancers in both Asian and Caucasian populations.
A number of different epidemiological studies have measured the association between the risk of d... more A number of different epidemiological studies have measured the association between the risk of different cancers and polymorphism at promoter region of 5′ untranslated region (5′-UTR) of the Ataxia-telangiectasia mutated (ATM) gene. However the results were contentious rather than conclusive. The current study was aimed at evaluating the association between the SNP (rs189037 G>A) and the risk of head and neck cancer and lung cancer by conducting ameta-analysis. A total of 9 case–control studieswere considered for this quantitative analysis. Stats Direct Statistical software (version 2.7.2)was used to evaluate the crude odds ratio (OR) with their 95% confidence interval (CI). The dominant model (GG vs. GA+ AA) showed no heterogeneity and the fixed effects pooled OR was found to be significant (OR = 1.14, 95% CI = 1.05–1.25) at p = 0.003. The pooled OR for fixed effects of heterozygote and homozygote mutant allele (GA vs. AA) model was significant (OR = 1.17, 95% CI = 1.04–1.30, p=0.006) and no heterogeneity was observed for this model. The current meta-analysis manifested that ATM rs189037 G>A genetic polymorphismmay contribute increased risk of head and neck and lung cancer. Moreover, the AA mutant allele was found to be related significantly with the prognosis of lung cancer and head and neck cancer
A number of different epidemiological studies have measured the association between the risk of d... more A number of different epidemiological studies have measured the association between the risk of different cancers and polymorphism at promoter region of 5′ untranslated region (5′-UTR) of the Ataxia-telangiectasia mutated (ATM) gene. However the results were contentious rather than conclusive. The current study was aimed at evaluating the association between the SNP (rs189037 G>A) and the risk of head and neck cancer and lung cancer by conducting ameta-analysis. A total of 9 case–control studieswere considered for this quantitative analysis. Stats Direct Statistical software (version 2.7.2)was used to evaluate the crude odds ratio (OR) with their 95% confidence interval (CI). The dominant model (GG vs. GA+ AA) showed no heterogeneity and the fixed effects pooled OR was found to be significant (OR = 1.14, 95% CI = 1.05–1.25) at p = 0.003. The pooled OR for fixed effects of heterozygote and homozygote mutant allele (GA vs. AA) model was significant (OR = 1.17, 95% CI =1.04–1.30, p=0.006) and no heterogeneity was observed for this model. The current meta-analysis manifested that ATM rs189037 G>A genetic polymorphismmay contribute increased risk of head and neck and lung cancer. Moreover, the AA mutant allele was found to be related significantly with the prognosis of lung cancer and head and neck cancer.
Background: Polymorphisms in the MDM2 309 (T>G) and TP53 72 (G>C) genes are reported to increase ... more Background: Polymorphisms in the MDM2 309 (T>G) and TP53 72 (G>C) genes are reported to increase the susceptibility to head and neck cancer (HNC) in various populations. The risk for HNC is also strongly associated with etiologic habits such as smoking, alcohol consumption and/or chewing of betel quid (BQ). In a case-control study, we investigated the significance of the above polymorphisms alone, and upon interaction with one another as well as with various etiologic habits in determining HNC risk in a Northeast Indian population. Materials and Methods: Genotyping at 309 MDM2 and 72 TP53 in 122 HNC patients and 86 cancer free healthy controls was performed by PCR using allele specific primers, and the results were confirmed by DNA sequencing. Results: Individuals with the GG mutant allele of MDM2 showed a higher risk for HNC in comparison to those with the TT wild type allele (OR=1.9, 95%CI: 1.1-3.3) (p=0.022). The risk was further increased in females by ~4-fold (OR=4.6, 95% CI: 1.1-19.4) (P=0.04). TP53 polymorphism did not contribute to HNC risk alone; however, interaction between the TP53 GC and MDM2 GG genotypes resulted in significant risk (OR=4.9, 95% CI: 0.2-105.1) (p=0.04). Smokers, BQ- chewers and alcohol consumers showed statistically significant and dosedependent increase in HNC risk, irrespective of the MDM2 genotype. Conclusions: MDM2 genotype could serve as an important predictive biomarker for HNC risk in the population of Northeast India.
In the present study, we investigated the effect of
the DNA repair gene polymorphisms XPD Asp312... more In the present study, we investigated the effect of
the DNA repair gene polymorphisms XPD Asp312Asn
(G>A), APE1 Asp148Glu (T>G), and MUTYH Tyr165Cys
(G>A) on the risk for head and neck cancer (HNC) in association
with tobacco use in a population of Northeast India. The
study subjects comprised of 80 HNC patients and 92 healthy
controls. Genotyping was performed using amplification refractory
mutation system—PCR (ARMS-PCR) for XPD
Asp312Asn (G>A) and PCR using confronting two-pair
primers (PCR-CTPP) for APE1 Asp148Glu (T>G) and
MUTYH Tyr165Cys (G>A). The XPD Asp/Asn genotype increased
the risk for HNC by 2-fold (odds ratio, OR=2.072;
95 % CI, 1.025–4.190; p<0.05). Interaction between APE1
Asp/Asp and XPD Asp/Asn as well as MUTYH Tyr/Tyr and
XPD Asp/Asn genotypes further increased the risk by 2.9
(OR=2.97; 95 % CI, 1.16–7.61; p<0.05) and 2.3 (OR=
2.37; 95 % CI, 1.11–5.10; p<0.05) folds, respectively. The
risk was further increased in heavy smokers with the XPD
Asp/Asn genotype and heavy tobacco chewers with XPD
Asn/Asn genotype by 7.7-fold (OR=7.749; 95 % CI, 2.53–
23.70; p<0.05) and 10-fold (OR=10; 95 % CI, 1.26–79.13;p<0.05), respectively. We thus conclude that the XPD
Asp312Asn and APE1 Asp148Glu polymorphisms increase
the risk for HNC in association with smoking and/or tobacco
chewing in the population under study.
A study was carried out to assess the hepatoprotective and hypoglycemic activity of the leaf extr... more A study was carried out to assess the hepatoprotective and hypoglycemic activity of the leaf extracts of Phyllanthus acidus in Wister albino rats against the widely used drugs i.e. Silymarin for hepatoprotective activity and Glibenclamide for hypoglycaemic activity. Phyllanthus acidus leaves were collected from different localities of Agartala, Tripura, India. Aqueous extract of P. acidus was analyzed in carbon tetra chloride induced jaundice rats to evaluate the hepatoprotective activity. Hepatic enzymes like transaminase (AST), alanine transaminase (ALT), alkaline phosphatase (ALP), and total bilirubin were estimated from the blood sample of rats on 8th day after treatment through semi auto analyzer. Alcoholic extract of P. acidus leaf was used to check hypoglycaemic activity in rats. Blood glucose level was estimated through glucose oxidase method on 0-2 hours after overnight fasting. The present study revealed that the aqueous extract of the leaf of P. acidus is as effective as the standard drug Silymarin in decreasing the hepatic markers in rats suffering from jaundice. It also revealed that the alcohol extract of P. acidus leaf possesses hypoglycemic activity at a dose of 200mg/Kg which is as effective as Glibenclamide, a commonly used drug for hypoglycaemic activity. The study revealed that the leaves of Phyllanthus acidus have both hepatoprotective and hypoglycemic activity on dose dependent manner just like commercial drugs available in the market. Further research is needed to understand the mode of action of the leaf extract of P. acidus in protecting liver and reducing blood sugar in rats at molecular level.
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Papers by ADITI BHOWMIK
and polymorphism at promoter region of 5′ untranslated region (5′-UTR) of the Ataxia-telangiectasia mutated
(ATM) gene. However the results were contentious rather than conclusive. The current study was aimed
at evaluating the association between the SNP (rs189037 G>A) and the risk of head and neck cancer and lung
cancer by conducting ameta-analysis. A total of 9 case–control studieswere considered for this quantitative analysis.
Stats Direct Statistical software (version 2.7.2)was used to evaluate the crude odds ratio (OR) with their 95%
confidence interval (CI). The dominant model (GG vs. GA+ AA) showed no heterogeneity and the fixed effects
pooled OR was found to be significant (OR = 1.14, 95% CI = 1.05–1.25) at p = 0.003. The pooled OR for fixed
effects of heterozygote and homozygote mutant allele (GA vs. AA) model was significant (OR = 1.17, 95% CI =
1.04–1.30, p=0.006) and no heterogeneity was observed for this model. The current meta-analysis manifested
that ATM rs189037 G>A genetic polymorphismmay contribute increased risk of head and neck and lung cancer.
Moreover, the AA mutant allele was found to be related significantly with the prognosis of lung cancer and head
and neck cancer
one another as well as with various etiologic habits in determining HNC risk in a Northeast Indian population.
Materials and Methods: Genotyping at 309 MDM2 and 72 TP53 in 122 HNC patients and 86 cancer free healthy
controls was performed by PCR using allele specific primers, and the results were confirmed by DNA sequencing.
Results: Individuals with the GG mutant allele of MDM2 showed a higher risk for HNC in comparison to those with the TT wild type allele (OR=1.9, 95%CI: 1.1-3.3) (p=0.022). The risk was further increased in females by ~4-fold (OR=4.6, 95% CI: 1.1-19.4) (P=0.04). TP53 polymorphism did not contribute to HNC risk alone; however, interaction between the TP53 GC and MDM2 GG genotypes resulted in significant risk (OR=4.9, 95%
CI: 0.2-105.1) (p=0.04). Smokers, BQ- chewers and alcohol consumers showed statistically significant and dosedependent
increase in HNC risk, irrespective of the MDM2 genotype. Conclusions: MDM2 genotype could serve as an important predictive biomarker for HNC risk in the population of Northeast India.
the DNA repair gene polymorphisms XPD Asp312Asn
(G>A), APE1 Asp148Glu (T>G), and MUTYH Tyr165Cys
(G>A) on the risk for head and neck cancer (HNC) in association
with tobacco use in a population of Northeast India. The
study subjects comprised of 80 HNC patients and 92 healthy
controls. Genotyping was performed using amplification refractory
mutation system—PCR (ARMS-PCR) for XPD
Asp312Asn (G>A) and PCR using confronting two-pair
primers (PCR-CTPP) for APE1 Asp148Glu (T>G) and
MUTYH Tyr165Cys (G>A). The XPD Asp/Asn genotype increased
the risk for HNC by 2-fold (odds ratio, OR=2.072;
95 % CI, 1.025–4.190; p<0.05). Interaction between APE1
Asp/Asp and XPD Asp/Asn as well as MUTYH Tyr/Tyr and
XPD Asp/Asn genotypes further increased the risk by 2.9
(OR=2.97; 95 % CI, 1.16–7.61; p<0.05) and 2.3 (OR=
2.37; 95 % CI, 1.11–5.10; p<0.05) folds, respectively. The
risk was further increased in heavy smokers with the XPD
Asp/Asn genotype and heavy tobacco chewers with XPD
Asn/Asn genotype by 7.7-fold (OR=7.749; 95 % CI, 2.53–
23.70; p<0.05) and 10-fold (OR=10; 95 % CI, 1.26–79.13;p<0.05), respectively. We thus conclude that the XPD
Asp312Asn and APE1 Asp148Glu polymorphisms increase
the risk for HNC in association with smoking and/or tobacco
chewing in the population under study.
and polymorphism at promoter region of 5′ untranslated region (5′-UTR) of the Ataxia-telangiectasia mutated
(ATM) gene. However the results were contentious rather than conclusive. The current study was aimed
at evaluating the association between the SNP (rs189037 G>A) and the risk of head and neck cancer and lung
cancer by conducting ameta-analysis. A total of 9 case–control studieswere considered for this quantitative analysis.
Stats Direct Statistical software (version 2.7.2)was used to evaluate the crude odds ratio (OR) with their 95%
confidence interval (CI). The dominant model (GG vs. GA+ AA) showed no heterogeneity and the fixed effects
pooled OR was found to be significant (OR = 1.14, 95% CI = 1.05–1.25) at p = 0.003. The pooled OR for fixed
effects of heterozygote and homozygote mutant allele (GA vs. AA) model was significant (OR = 1.17, 95% CI =
1.04–1.30, p=0.006) and no heterogeneity was observed for this model. The current meta-analysis manifested
that ATM rs189037 G>A genetic polymorphismmay contribute increased risk of head and neck and lung cancer.
Moreover, the AA mutant allele was found to be related significantly with the prognosis of lung cancer and head
and neck cancer
one another as well as with various etiologic habits in determining HNC risk in a Northeast Indian population.
Materials and Methods: Genotyping at 309 MDM2 and 72 TP53 in 122 HNC patients and 86 cancer free healthy
controls was performed by PCR using allele specific primers, and the results were confirmed by DNA sequencing.
Results: Individuals with the GG mutant allele of MDM2 showed a higher risk for HNC in comparison to those with the TT wild type allele (OR=1.9, 95%CI: 1.1-3.3) (p=0.022). The risk was further increased in females by ~4-fold (OR=4.6, 95% CI: 1.1-19.4) (P=0.04). TP53 polymorphism did not contribute to HNC risk alone; however, interaction between the TP53 GC and MDM2 GG genotypes resulted in significant risk (OR=4.9, 95%
CI: 0.2-105.1) (p=0.04). Smokers, BQ- chewers and alcohol consumers showed statistically significant and dosedependent
increase in HNC risk, irrespective of the MDM2 genotype. Conclusions: MDM2 genotype could serve as an important predictive biomarker for HNC risk in the population of Northeast India.
the DNA repair gene polymorphisms XPD Asp312Asn
(G>A), APE1 Asp148Glu (T>G), and MUTYH Tyr165Cys
(G>A) on the risk for head and neck cancer (HNC) in association
with tobacco use in a population of Northeast India. The
study subjects comprised of 80 HNC patients and 92 healthy
controls. Genotyping was performed using amplification refractory
mutation system—PCR (ARMS-PCR) for XPD
Asp312Asn (G>A) and PCR using confronting two-pair
primers (PCR-CTPP) for APE1 Asp148Glu (T>G) and
MUTYH Tyr165Cys (G>A). The XPD Asp/Asn genotype increased
the risk for HNC by 2-fold (odds ratio, OR=2.072;
95 % CI, 1.025–4.190; p<0.05). Interaction between APE1
Asp/Asp and XPD Asp/Asn as well as MUTYH Tyr/Tyr and
XPD Asp/Asn genotypes further increased the risk by 2.9
(OR=2.97; 95 % CI, 1.16–7.61; p<0.05) and 2.3 (OR=
2.37; 95 % CI, 1.11–5.10; p<0.05) folds, respectively. The
risk was further increased in heavy smokers with the XPD
Asp/Asn genotype and heavy tobacco chewers with XPD
Asn/Asn genotype by 7.7-fold (OR=7.749; 95 % CI, 2.53–
23.70; p<0.05) and 10-fold (OR=10; 95 % CI, 1.26–79.13;p<0.05), respectively. We thus conclude that the XPD
Asp312Asn and APE1 Asp148Glu polymorphisms increase
the risk for HNC in association with smoking and/or tobacco
chewing in the population under study.