Med Oncol (2014) 31:827 DOI 10.1007/s12032-013-0827-x
ORIGINAL PAPER
Vitamin D receptor gene polymorphisms and esophageal cancer risk in a Chinese population: a negative study Haiyong Gu • Xu Wang • Liang Zheng • Weifeng Tang • Changqing Dong Liming Wang • Yijun Shi • Aizhong Shao • Guowen Ding • Chao Liu • Ruiping Liu • Suocheng Chen • Jun Yin
•
Received: 22 October 2013 / Accepted: 20 December 2013 / Published online: 1 January 2014 Ó Springer Science+Business Media New York 2013
Abstract Vitamin D receptor (VDR) gene polymorphisms have been reported to influence susceptibility to some malignant cancers. However, there were few published findings on the association between VDR polymorphisms and esophageal cancer susceptibility. Our investigation was aimed to obtain a precise estimation of the association between VDR polymorphisms and esophageal cancer susceptibility. We conducted a hospital-based case–control study to evaluate the genetic effects of functional single-nucleotide polymorphisms VDR rs2107301 T[C, rs2228570 C[T, rs1989969 C[T and rs11568820 G[A on the development of esophageal cancer. A total of 629 esophageal squamous cell carcinoma (ESCC) cases and 686 controls were enrolled for this study. The Haiyong Gu and Xu Wang have contributed equally to this work. H. Gu X. Wang W. Tang C. Dong Y. Shi A. Shao G. Ding C. Liu S. Chen (&) J. Yin (&) Department of Cardiothoracic Surgery, Affiliated People’s Hospital of Jiangsu University, 8 Dianli Rd, Zhenjiang 212002, China e-mail: [email protected]
genotypes were determined using ligation detection reaction method. There were no significant associations between the four VDR variants and ESCC risk. Stratified analyses indicated a significantly increased risk of ESCC associated with VDR rs2107301 T[C polymorphism among patients who were drinking. These findings demonstrated that the risk of ESCC associated with VDR rs2107301 T[C polymorphism may be modified by lifestyle factors such as drinking. However, the results should be validated in larger well-designed studies in future. Keywords VDR Polymorphisms Esophageal cancer Molecular epidemiology Abbreviations VDR Vitamin D receptor LD Linkage disequilibrium OR Odds ratio CI Confidential interval SNPs Single-nucleotide polymorphisms ESCC Esophageal squamous cell carcinoma
J. Yin e-mail: [email protected] L. Zheng Department of Cardiothoracic Surgery, The First People’s Hospital of Changzhou and The Third Affiliated Hospital of Suzhou University, Changzhou 213003, China L. Wang Cancer Institute, Department of Chemotherapy, People’s Hospital Affiliated to Jiangsu University, Zhenjiang 212002, Jiangsu, China R. Liu Department of Orthopedics, Affiliated Hospital of Nanjing Medical University, Changzhou Second People’s Hospital, Changzhou 213003, China
Introduction Vitamin D has potent antitumor effects, and several investigations have demonstrated that 1,25-dihydroxy vitamin D3 [1,25(OH)2D3], the active form of vitamin D, plays an essential role in the development of cancers by regulating the expression of tumor-related genes or mediating inhibition of growth of cancer cells [1, 2]. The vitamin D receptor (VDR), a nuclear transcription factor that belongs to the steroid hormone receptor family, mediates
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gene expression of vitamin D [3] and most of the effects of active vitamin D in a wide variety of tissues [4]. VDR plays a major role in regulating cell proliferation, differentiation and induction of apoptosis [5]. VDR is more likely to contribute to cancer carcinogenesis. VDR polymorphisms may influence gene transcription through regulating messenger RNA (mRNA) stability [6], and also among these variants, one single-nucleotide polymorphism (SNP) rs2228570 that has been shown to affect VDR protein structure [7], leading to a change in the biological functions of vitamin D and eventually participating in tumorigenesis. Previous studies demonstrated that lower solar radiation areas have higher rates of esophageal cancer [8, 9]. Lower exposure to type-B ultraviolet radiation leads to lower production of vitamin D. However, the speculation of the relationship between risk of esophageal squamous cell carcinoma (ESCC) and vitamin D status was discrepant [10, 11]. A recent study from China reported that serum 25-hydroxy vitamin D [25(OH)D] was associated with an increased risk of squamous dysplasia, the precursor lesion for ESCC [12]. The phenomenon may be explained by the higher level of serum vitamin D, which may be due to the functional deficit of VDR. As VDR is necessary for the effects of vitamin D to fully take place [13], a plausible hypothesis can be made that the VDR polymorphisms may alter the ESCC susceptibility. In this study, we conducted a hospital-based case–control study to evaluate the genetic effects of four functional SNPs VDR rs2107301 T[C, VDR rs2228570 C[T, VDR rs1989969 C[T and VDR rs11568820 G[A on the development of ESCC.
Med Oncol (2014) 31:827
(Zhenjiang, China) between October 2008 and December 2010. All cases of esophageal cancer were diagnosed as ESCC by pathologic methods. The exclusion criteria were patients who previously had cancer, any metastasized cancer, radiotherapy or chemotherapy. The 686 controls were patients without cancer frequency-matched to the cases with regard to age (±5 years) and sex recruited from the four hospitals mentioned above during the same time period. Most of the controls were admitted to the hospitals for the treatment of trauma. All subjects were personally questioned by trained interviewers using a pretested questionnaire to obtain information on demographic data (e.g., age, sex) and related risk factors (including tobacco smoking and alcohol consumption). After the interview, 2-mL samples of venous blood were collected from each subject. Individuals who smoked one cigarette per day for [1 year were defined as ‘‘smokers’’. Subjects who consumed C3 alcoholic drinks a week for [6 months were considered to be ‘‘alcohol drinkers’’. Isolation of DNA and genotyping by ligation detection reaction Blood samples were collected from patients using Vacutainers and transferred to tubes lined with ethylenediaminetetraacetic acid (EDTA). Genomic DNA was isolated from whole blood with the QIAamp DNA Blood Mini Kit (Qiagen, Berlin, Germany). The samples were genotyped using the ligation detection reaction (LDR) method with technical support from the Shanghai Biowing Applied Biotechnology Company as previously described [14]. For quality control, repeated analyses were done for 160 (12.17 %) randomly selected samples with high DNA quality.
Patients and methods Statistical analyses Ethical approval of the study protocol This hospital-based case–control study was approved by the Review Board of Jiangsu University (Zhenjiang, China). We have complied with the World Medical Association Declaration of Helsinki regarding ethical conduct of research involving human subjects and/or animals. All subjects provided written informed consent to be included in the study. Study subjects 629 subjects with esophageal cancer were consecutively recruited from the Affiliated People’s Hospital of Jiangsu University and Affiliated Hospital of Jiangsu University
123
Differences in the distributions of demographic characteristics, selected variables and genotypes of the VDR rs2107301 T[C, rs2228570 C[T, rs1989969 C[T and rs11568820 G[A variants between the cases and controls were evaluated using the v2 test. The associations between these four variants and risk of ESCC were estimated by computing the ORs and their 95 % CIs using logistic regression analyses for crude ORs and adjusted ORs when adjusting for age, sex, smoking and drinking status. The Hardy–Weinberg equilibrium (HWE) was tested by a goodness-of-fit v2 test to compare the observed genotype frequencies to the expected ones among the control subjects. All statistical analyses were performed with SAS 9.1.3 (SAS Institute, Cary, NC, USA).
Med Oncol (2014) 31:827
Page 3 of 7 827
Table 1 Distribution of selected demographic variables and risk factors in ESCC cases and controls Variable
Cases (n = 629) n
Age (years) mean ± SD
pa
Controls (n = 686) %
n
62.85 (± 8.13)
% 62.58 (± 7.89)
0.541
Age (years)
0.155
\63
310
49.28
365
53.21
C63
319
50.72
321
46.79
444
70.59
461
67.20
185
29.41
225
32.80
Sex
0.185
Male Female Tobacco use
ORIGINAL PAPER
Vitamin D receptor gene polymorphisms and esophageal cancer risk in a Chinese population: a negative study Haiyong Gu • Xu Wang • Liang Zheng • Weifeng Tang • Changqing Dong Liming Wang • Yijun Shi • Aizhong Shao • Guowen Ding • Chao Liu • Ruiping Liu • Suocheng Chen • Jun Yin
•
Received: 22 October 2013 / Accepted: 20 December 2013 / Published online: 1 January 2014 Ó Springer Science+Business Media New York 2013
Abstract Vitamin D receptor (VDR) gene polymorphisms have been reported to influence susceptibility to some malignant cancers. However, there were few published findings on the association between VDR polymorphisms and esophageal cancer susceptibility. Our investigation was aimed to obtain a precise estimation of the association between VDR polymorphisms and esophageal cancer susceptibility. We conducted a hospital-based case–control study to evaluate the genetic effects of functional single-nucleotide polymorphisms VDR rs2107301 T[C, rs2228570 C[T, rs1989969 C[T and rs11568820 G[A on the development of esophageal cancer. A total of 629 esophageal squamous cell carcinoma (ESCC) cases and 686 controls were enrolled for this study. The Haiyong Gu and Xu Wang have contributed equally to this work. H. Gu X. Wang W. Tang C. Dong Y. Shi A. Shao G. Ding C. Liu S. Chen (&) J. Yin (&) Department of Cardiothoracic Surgery, Affiliated People’s Hospital of Jiangsu University, 8 Dianli Rd, Zhenjiang 212002, China e-mail: [email protected]
genotypes were determined using ligation detection reaction method. There were no significant associations between the four VDR variants and ESCC risk. Stratified analyses indicated a significantly increased risk of ESCC associated with VDR rs2107301 T[C polymorphism among patients who were drinking. These findings demonstrated that the risk of ESCC associated with VDR rs2107301 T[C polymorphism may be modified by lifestyle factors such as drinking. However, the results should be validated in larger well-designed studies in future. Keywords VDR Polymorphisms Esophageal cancer Molecular epidemiology Abbreviations VDR Vitamin D receptor LD Linkage disequilibrium OR Odds ratio CI Confidential interval SNPs Single-nucleotide polymorphisms ESCC Esophageal squamous cell carcinoma
J. Yin e-mail: [email protected] L. Zheng Department of Cardiothoracic Surgery, The First People’s Hospital of Changzhou and The Third Affiliated Hospital of Suzhou University, Changzhou 213003, China L. Wang Cancer Institute, Department of Chemotherapy, People’s Hospital Affiliated to Jiangsu University, Zhenjiang 212002, Jiangsu, China R. Liu Department of Orthopedics, Affiliated Hospital of Nanjing Medical University, Changzhou Second People’s Hospital, Changzhou 213003, China
Introduction Vitamin D has potent antitumor effects, and several investigations have demonstrated that 1,25-dihydroxy vitamin D3 [1,25(OH)2D3], the active form of vitamin D, plays an essential role in the development of cancers by regulating the expression of tumor-related genes or mediating inhibition of growth of cancer cells [1, 2]. The vitamin D receptor (VDR), a nuclear transcription factor that belongs to the steroid hormone receptor family, mediates
123
827 Page 2 of 7
gene expression of vitamin D [3] and most of the effects of active vitamin D in a wide variety of tissues [4]. VDR plays a major role in regulating cell proliferation, differentiation and induction of apoptosis [5]. VDR is more likely to contribute to cancer carcinogenesis. VDR polymorphisms may influence gene transcription through regulating messenger RNA (mRNA) stability [6], and also among these variants, one single-nucleotide polymorphism (SNP) rs2228570 that has been shown to affect VDR protein structure [7], leading to a change in the biological functions of vitamin D and eventually participating in tumorigenesis. Previous studies demonstrated that lower solar radiation areas have higher rates of esophageal cancer [8, 9]. Lower exposure to type-B ultraviolet radiation leads to lower production of vitamin D. However, the speculation of the relationship between risk of esophageal squamous cell carcinoma (ESCC) and vitamin D status was discrepant [10, 11]. A recent study from China reported that serum 25-hydroxy vitamin D [25(OH)D] was associated with an increased risk of squamous dysplasia, the precursor lesion for ESCC [12]. The phenomenon may be explained by the higher level of serum vitamin D, which may be due to the functional deficit of VDR. As VDR is necessary for the effects of vitamin D to fully take place [13], a plausible hypothesis can be made that the VDR polymorphisms may alter the ESCC susceptibility. In this study, we conducted a hospital-based case–control study to evaluate the genetic effects of four functional SNPs VDR rs2107301 T[C, VDR rs2228570 C[T, VDR rs1989969 C[T and VDR rs11568820 G[A on the development of ESCC.
Med Oncol (2014) 31:827
(Zhenjiang, China) between October 2008 and December 2010. All cases of esophageal cancer were diagnosed as ESCC by pathologic methods. The exclusion criteria were patients who previously had cancer, any metastasized cancer, radiotherapy or chemotherapy. The 686 controls were patients without cancer frequency-matched to the cases with regard to age (±5 years) and sex recruited from the four hospitals mentioned above during the same time period. Most of the controls were admitted to the hospitals for the treatment of trauma. All subjects were personally questioned by trained interviewers using a pretested questionnaire to obtain information on demographic data (e.g., age, sex) and related risk factors (including tobacco smoking and alcohol consumption). After the interview, 2-mL samples of venous blood were collected from each subject. Individuals who smoked one cigarette per day for [1 year were defined as ‘‘smokers’’. Subjects who consumed C3 alcoholic drinks a week for [6 months were considered to be ‘‘alcohol drinkers’’. Isolation of DNA and genotyping by ligation detection reaction Blood samples were collected from patients using Vacutainers and transferred to tubes lined with ethylenediaminetetraacetic acid (EDTA). Genomic DNA was isolated from whole blood with the QIAamp DNA Blood Mini Kit (Qiagen, Berlin, Germany). The samples were genotyped using the ligation detection reaction (LDR) method with technical support from the Shanghai Biowing Applied Biotechnology Company as previously described [14]. For quality control, repeated analyses were done for 160 (12.17 %) randomly selected samples with high DNA quality.
Patients and methods Statistical analyses Ethical approval of the study protocol This hospital-based case–control study was approved by the Review Board of Jiangsu University (Zhenjiang, China). We have complied with the World Medical Association Declaration of Helsinki regarding ethical conduct of research involving human subjects and/or animals. All subjects provided written informed consent to be included in the study. Study subjects 629 subjects with esophageal cancer were consecutively recruited from the Affiliated People’s Hospital of Jiangsu University and Affiliated Hospital of Jiangsu University
123
Differences in the distributions of demographic characteristics, selected variables and genotypes of the VDR rs2107301 T[C, rs2228570 C[T, rs1989969 C[T and rs11568820 G[A variants between the cases and controls were evaluated using the v2 test. The associations between these four variants and risk of ESCC were estimated by computing the ORs and their 95 % CIs using logistic regression analyses for crude ORs and adjusted ORs when adjusting for age, sex, smoking and drinking status. The Hardy–Weinberg equilibrium (HWE) was tested by a goodness-of-fit v2 test to compare the observed genotype frequencies to the expected ones among the control subjects. All statistical analyses were performed with SAS 9.1.3 (SAS Institute, Cary, NC, USA).
Med Oncol (2014) 31:827
Page 3 of 7 827
Table 1 Distribution of selected demographic variables and risk factors in ESCC cases and controls Variable
Cases (n = 629) n
Age (years) mean ± SD
pa
Controls (n = 686) %
n
62.85 (± 8.13)
% 62.58 (± 7.89)
0.541
Age (years)
0.155
\63
310
49.28
365
53.21
C63
319
50.72
321
46.79
444
70.59
461
67.20
185
29.41
225
32.80
Sex
0.185
Male Female Tobacco use
