Annals of Oncology Advance Access originally published online on April 10, 2007
Annals of Oncology 2007 18(6):1030-1036; doi:10.1093/annonc/mdm085
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© 2007 European Society for Medical Oncology
gastrointestinal tumors |
Vascular endothelial growth factor gene polymorphisms associated with prognosis for patients with gastric cancer
1 Department of Oncology/Hematology
2 Department of Pathology
3 Department of Internal Medicine and Biochemistry
4 Department of the Advanced Medical Technology Center for Diagnosis and Prediction
5 Department of Surgery, Kyungpook National University Hospital, Kyungpook National University School of Medicine, Daegu, Korea
* Correspondence to: Dr J. G. Kim, Department of Oncology/Hematology, Kyungpook National University Hospital, Kyungpook National University School of Medicine, 50 Samduck 2-Ga, Jung-Gu, Daegu 700-712, South Korea. Tel: +82-53-420-6522; Fax: +82-53-426-2046; E-mail: jkk21c{at}mail.knu.ac.kr
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Abstract |
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Background: The present study analyzed vascular endothelial growth factor (VEGF) gene polymorphisms and their impact on the prognosis for patients with gastric cancer.
Patients and methods: Five hundred and three consecutive patients with surgically resected gastric adenocarcinoma were enrolled in the present study. The genomic DNA was extracted from paraffin-embedded tissue and four VEGF (–460T > C, –116G > A, +405G > C, and +936C > T) gene polymorphisms were determined using a polymerase chain reaction-restriction fragment length polymorphism assay.
Results: The survival analysis showed no association of three VEGF gene polymorphisms with the prognosis. For the +936C > T polymorphism, the T/T genotype, however, had a worse overall survival (OS) compared with the C/C genotype (P = 0.037). The –460 T/C or C/C genotype was a poor prognostic factor in patients with stage 0 or I gastric cancer (OS: hazard ratio (HR) = 3.96, disease-free survival (DFS): HR = 4.87). In the haplotype analysis, the CACC haplotype was associated with a significantly worse survival when compared with the TGGC haplotype (OS: HR = 1.72, DFS: HR = 1.73).
Conclusions: VEGF gene polymorphisms were found to be an independent prognostic marker for patients with gastric cancer. Consequently, the analysis of VEGF gene polymorphisms can help identify patient subgroups at high risk of a poor disease outcome.
Key words: gastric cancer, gene, polymorphism, prognosis, VEGF
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introduction |
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Although gastric cancer is increasingly being diagnosed at an early stage, resulting in 10-year survival rates of between 80% and 95% in the Far East, gastric adenocarcinoma is still the second leading cause of cancer-related death worldwide [1, 2].
Angiogenesis, the formation of new blood vessels from endothelial precursors, is a prerequisite for the growth and progression of solid malignancies, and the vascular endothelial growth factor (VEGF) superfamily of endothelial growth factors has been identified to critically influence tumor-related angiogenesis [3, 4]. Clinical studies have demonstrated that an increased expression of VEGF or its family is associated with the grade of angiogenesis and the prognosis for various human cancers [5–8]. In particular, with gastric cancer, the expression of VEGF or VEGF-C, which are intimately involved in the regulation of the lymphangiogenic process, has been reported to be correlated with a poor prognosis [9–11]. Furthermore, Juttner et al. [12] found that the presence of VEGF-D and its receptor vascular endothelial growth factor receptor 3 was associated with lymphatic metastasis, reduced patient survival, and poor prognosis after the curative resection of gastric adenocarcinomas. Given these results, VEGF or its family would seem to play an important role in lymphangiogenesis and lymphatic tumor spread, thereby affecting the prognosis of gastric cancer.
The VEGF gene is assigned to chromosome 6p12-p21 and consists of eight exons separated by seven introns that exhibit alternative splicing to form a family of proteins [13, 14]. Several polymorphisms have been described in the VEGF gene, and some of these variants [–460T > C, –116G > A, and +405G > C (transcription start site counted as +1) in the promoter or 5'-untranslated region and +936C > T in the 3'-untranslated region] found to be associated with variations in VEGF protein production [15–17]. In clinical studies, these polymorphisms have been reported to be involved in the development of solid tumors, such as melanoma [18], lung [19], prostate [20], and breast cancer [21], where angiogenesis is critical in the pathogenesis of the disease. Moreover, recent studies have demonstrated that genetic polymorphisms can be used to predict the clinical outcomes of gastric [22], breast [23, 24], colon [25], and pancreatic cancer [26].
No study, however, has yet been published that has investigated the single nucleotide polymorphisms (SNPs) of the VEGF gene and their relationship to the clinical outcomes of gastric cancer. Therefore, the present study analyzed four VEGF gene polymorphisms and their impact on the prognosis for patients with gastric adenocarcinoma.
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study population
All the tissues investigated in this study were obtained from consecutive Korean patients (n = 503) who had undergone a surgical gastrectomy between January 2000 and December 2001 at Kyungpook National University Hospital (Daegu, Korea). Written informed consent for gene expression analyses including SNPs was received from all the patients before surgery, and the study was approved by the Institutional Research Board at Kyungpook National University Hospital. The diagnosis and staging of gastric carcinoma were assessed according to the World Health Organization classifications [27] and tumor–node–metastasis (TNM) classifications set out by the American Joint Committee on Cancer [28].
genotyping of VEGF gene polymorphisms
The genomic DNA was extracted from paraffin-embedded tumor bearing tissue using a Wizard genomic DNA purification kit (Promega, Madison, WI). The VEGF –460T > C, –116G > A, +405G > C, and +936C> T polymorphisms were then determined using a polymerase chain reaction-restriction fragment length polymorphism assay. Based on the GenBank reference sequence (accession no. NT_007592
[GenBank]
), the PCR primers designed for –460T > C, –116G > A, +405G > C, and +936C > T were 5'-CCTCTTTAGCCAGAGCCG-GGG-3' (forward) and 5'-TGGCCTTCTCCCCGCTCCGAC-3' (reverse); 5'-TCCTGCTCCCTCCTCGCCAAATG-3' (forward) and 5'-GGCGGGGACAGGCGAGCCTC-3' (reverse); 5'-CGACGGCTTGGGGAGATTGC-3' (forward) and 5'-GGGCGGTGTCTGTCTGTCTG-3' (reverse); and 5'-CTCGGTGATTTAGCAGCAAG-3' (forward) and 5'-CTCGGTGATTTAGCAGCAAG-3' (reverse), respectively. The PCR reactions were carried out in a 20-µl reaction volume containing 100 ng genomic DNA, 25 pmol/l each primer, 0.2 mmol/l deoxyuceotide triphosphates, 10 mmol/l Tris–HCl (pH 8.3), 50 mmol/l KCl, 1.5 mmol/l MgCl2, and 1 unit of Taq polymerase (Takara Shuzo Co., Otsu, Shiga, Japan). The PCR cycle conditions consisted of an initial denaturation step at 94°C for 5 min, followed by 35 cycles of 30 s at 94°C, 30 s at 62°, 30 s at 72°C, and a final elongation at 72°C for 10 min. The PCR products were digested overnight with the appropriate restriction enzymes (New England BioLabs, Beverly, MA), which were BsaHI, MnlI, BsmFI, and NlaIII for the –460T > C, –116G > A, +405G > C, and +936C> T polymorphisms, respectively. The digested PCR products were resolved on a 3% agarose gel and stained with ethidium bromide for visualization under UV light. For quality control, the genotyping analysis was done blind as regards the subjects. The selected PCR-amplified DNA samples (n = 2, for each genotype) were also examined by DNA sequencing to confirm the genotyping results.
immunohistochemistry
Formalin fixed, paraffin-embedded serial sections (4 µm) mounted on 3-aminopropyltriethoxysilane-coated slides (Matsunami Glass Ind. Ltd, Kasamatsu, Japan) were deparaffinized in xylene alcohol and graded alcohol. Rabbit polyclonal anti-VEGF (Santa Cruz Biotechnology, Inc., Santa Cruz, CA) and anti-VEGF-C (Zymed Laboratories, San Francisco, CA) antibodies were used at concentrations of 1.6 µg/ml and 2.0 µg/ml, respectively. The immunohistochemistry was carried out using a catalyzed signal amplification system (Dako, Ely, UK) according to the manufacturer's protocol. The sections were treated with 0.3% hydrogen peroxide (H2O2) in water for 10 min to quench any endogenous peroxidase activity within the tissue, and the nonspecific binding sites blocked with a 20% heat-inactivated nonserum protein for 10 min at room temperature. Next, the sections were incubated for 15 min in the presence of the primary antibody, then the slides were washed in phosphate buffered saline (PBS) containing 0.1% Tween 20 (PBS/Tween) for 15 min while changing the solution three times before the application of the secondary biotinylated antibody. The slides were incubated with the secondary antibody for 15 min at room temperature before being washed for 15 min in PBS/Tween that was changed three times. The sections were then incubated for 15 min with an avidin–biotinylated horseradish peroxidase complex, and the reaction visualized with 0.02% 3,3'-diaminobenzidine tetrahydrochloride as a chromogen in a Tris–HCl buffer, pH 7.6, containing 0.03% H2O2. Hematoxylin was used to counterstain the nuclei. The staining results for VEGF and VEGF-C were classified by estimating the percentage of epithelial cells showing specific immunoreactivity: grade 0 (0%–10% positive cells), grade I (10%–50% positive cells), and grade II (>50% positive cells). Two pathologists (HB and GY) blindly examined all the slides.
statistical analysis
The genotypes for each SNP were analyzed as a three-group categoric variable (referent model), and those were also grouped according to the dominant and recessive model. The haplotypes and their frequencies were estimated using the Bayesian algorithm in the phase program [29], which is available at http://www.stat.washington.edu/stephens/phase.html. The correlation between the level of VEGF or VEGF-C protein expression and four VEGF gene polymorphisms was analyzed using chi-square test and logistic regression analysis. Overall survival (OS) was measured from the day of surgery until the date of death or last follow-up. Disease-free survival (DFS) was calculated from the day of surgery until recurrence or death from any cause. The survival estimates were calculated using the Kaplan–Meier method. The differences in OS or DFS according to the four VEGF gene polymorphisms were compared using log-rank tests. Coxs proportional hazards regression model was used for the multivariate survival analyses, and the analyses were always adjusted for age (<60 versus 
60 years), sex (male versus female), stage (0–IV), and adjuvant chemotherapy (i.v. versus oral versus not received). The hazard ratio (HR) and 95% confidence interval (CI) were also estimated. The multivariate analyses were carried out on 492 out of 503 patients, as haplotype data were unavailable for 11 patients.
A cut-off P value of 0.05 was adopted for all the statistical analyses. The statistical data were obtained using an SPSS software package (SPSS 11.5 Inc., Chicago, IL) or SAS Genetic software (SAS Institute, Cary, NC).
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patient characteristics and survival analysis
The median age of the patients was 60 (range, 25–83) years, and 337 (67.0%) patients were male. Curative resections (gastrectomy with more than D1 lymph node dissection) were carried out in 479 (97.2%) patients, while the others received a palliative gastrectomy. The pathologic stages after the surgical resection were as follows: stage 0 (n = 5, 1.0%), stage IA (n = 172, 34.2%), stage IB (n = 106, 21.1%), stage II (n = 105, 20.9%), stage IIIA (n = 47, 9.3%), stage IIIB (n = 26, 5.2%), and stage IV (n = 42, 8.3%). Among the 220 patients with stage II–IV diseases, 167 (75.9%) patients received adjuvant chemotherapy with four cycles of 5-fluorouracil (5-FU) + epirubicin (n = 69) or nimustine (n = 12) followed by oral 5-FU for 1 year or just oral 5-FU for 1 year (n = 86). At the time of last analysis (January 2006), 111 patients had experienced a disease relapse and 103 patients had died as a result of gastric cancer. The death of 6 patients, however, was not related to gastric cancer. The estimated 5-year OS and DFS for all the patients was 78.4 ± 1.85% and 77.4 ± 1.87%, respectively.
genotype frequency and effects on survival
The four VEGF gene polymorphisms were successfully amplified in 98%–99% of the cases. The frequencies of each genotype are shown in Table 1. The –460T > C and +405G > C or +936C > T polymorphisms exhibited a strong linkage disequilibrium (correlation coefficient, R = 0.26; Lewontin's D', D' = 0.79 or correlation coefficient, R = 0.39; Lewontin's D', D' = 0.91) in the study population, whereas the linkage with the –116G > A polymorphisms was weaker (correlation coefficient, R = 0.09; Lewontin's D', D' = 0.65). The survival analysis showed no association between the three VEGF gene polymorphisms (–460T > C, –116G > A, and +405G > C) and the prognosis. For the +936C > T polymorphism, the T/T genotype, however, exhibited a worse OS compared with the C/C genotype (HR = 3.23; 95% CI, 1.13–9.25; P = 0.037), although no significant difference was observed in the dominant or recessive model (Table 1). When confined to the patients with stage 0 or I gastric cancer, the OS and DFS for the patients with the –460 T/C or C/C genotype (dominant model) were worse than those for the patients with the –460 T/T genotype in the multivariate analysis (OS: HR = 3.96, 95% CI, 1.08–14.52, P = 0.038; DFS: HR = 4.87, 95% CI, 1.36–17.43, P = 0.015, Table 2 and Figure 1), meanwhile the other polymorphisms had no significant effect on survival.
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haplotype analysis
The haplotype analyses were conducted to evaluate the combined effect of the four polymorphisms on gastric cancer survival. Fourteen haplotypes (TGGC 46.2%; TGGT 7.9%; TGCC 17.0%; TGCT 0.2%; TAGC 0.7%; TACC 2.0%; CGGC 4.1%; CGGT 0.1%; CGCC 5.6%; CGCT 3.2%; CAGC 0.9%; CAGT 1.3%; CACC 6.5%; and CACT 4.3%;) were estimated from the four polymorphisms in 492 (97.8%) out of 503 cases. Since TGGC, TGGT, TGCC, CGCC, and CACC were the common haplotypes, the impact of these haplotypes on survival was analyzed (Table 3). The estimated 5-year OS and DFS rates for the patients with the CACC haplotype were 73.4 ± 5.5% and 74.6 ± 5.5%, respectively, which were significantly inferior to the rates for the patients with the TGGC haplotype (OS: HR = 1.72, 95% CI, 1.02–2.89; P = 0.041, DFS: HR = 1.73, 95% CI, 1.03–2.92; P = 0.038, Table 3 and Figure 2). In a Cox model for OS that included the age, TNM stage, and adjuvant chemotherapy, the TNM stage remained a significant prognostic factor (P < 0.001).
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immunostaining of VEGF proteins
The VEGF and VEGF-C protein expression was evaluated by immunohistochemical staining in 374 (74.4%) and 371 (73.8%) cases, respectively. No correlation was detected with the level of VEGF or VEGF-C protein expression and any of the four VEGF gene polymorphisms analyzed (data not shown). Also, no correlation was observed with any other clinicopathologic variables. Finally, no association between the grade of immunostaining and the OS or DFS was observed (Table 4).
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discussion |
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We have investigated the prognostic impact of four VEGF gene polymorphisms in quite a large population of patients with surgically resected gastric adenocarcinoma. The current study demonstrated that CAGG haplotype or –460 T/C–C/C genotype was a poor prognostic factor in these patients.
The role of genetic polymorphisms, which is an important determinant of endogenous causes of cancer, in relation to the risk for gastric cancer has attracted increasing interest, probably because of advances in DNA analysis technologies and human genome knowledge. Most previous studies, however, have only addressed the effect of genetic variants of metabolic enzymes and inflammation mediators [30]. Since VEGF or its family plays a critical role in tumor-related angiogenesis, the association of VEGF gene polymorphisms with the risk or prognosis of several solid tumors, such as melanoma [18], lung [19], prostate [20], and breast cancer [21, 23, 24], has already been demonstrated.
The genotype frequencies of –460T > C, +405G > C or +936C > T in the present study were similar to those previously reported for the Korean [19], Chinese [23], and European populations [16, 21, 24], whereas the frequency of the –116 G/G genotype was higher than that for European patients (68.3% versus 42.1%) [24]. The –460T > C and +405G > C polymorphisms exhibited a strong linkage disequilibrium in the present study population, while the linkage between the –460T > C and –116G > A polymorphisms was weak, which is consistent with findings from an earlier study [15, 19, 23].
In the present study, the CACC haplotype was associated with a significantly worse survival when compared with the TGGC haplotype in patients with surgically resected gastric cancer (OS: HR = 1.72, DFS: HR = 1.73), and the –460 T/C or C/C genotype was a poor prognostic factor in patients with stage 0 or I gastric cancer (OS: HR = 3.957, DFS: HR = 4.870). In a recent study by Lu et al. [23] that also evaluated the effects of three VEGF gene polymorphisms (–460T > C, +405G > C, and +936C> T) on survival in 1193 Chinese patients with breast cancer, the survival was lower among the patients with the –460 C/C and +405 G/G genotypes and higher among the patients with the –460T/+405C/+936C haplotype. One possible explanation for these results is that the DNA sequence variations in the VEGF gene may alter VEGF production and/or activity, thereby causing interindividual differences in the lymphangiogenesis and lymphatic tumor spread. Given the homogenous ethnic background of Korean patients, any potential confounding effect due to ethnicity is likely to be small in the present study. The correlation between an elevated preoperative serum VEGF concentration and the poor survival in patients with gastric cancer was already demonstrated in previous study [31]. A few studies, however, have reported that VEGF gene polymorphisms are associated with VEGF production. Nonetheless, the results are inconsistent. Awata et al. [32] reported that individuals with the +405 C/C genotype had a higher fasting serum VEGF level than those with other genotypes, and that they carried an increased risk of diabetic retinopathy. Meanwhile, Watson et al. [15] documented that the +405G allele is associated with higher lipopolysaccharide-stimulated VEGF production by peripheral blood mononuclear cells than the +405C allele. In a recent in vitro study [17], carrying a haplotype containing the –460C/+405G polymorphisms was found to significantly increase basal VEGF promoter activity and phorbol ester-induced responsiveness compared with the presence of a haplotype containing the –460T/+405C polymorphisms.
In the present study, any of the four VEGF gene polymorphisms was not correlated with the level of VEGF or VEGF-C protein expression. Koukourakis et al. [33] reported that –2578 C/C, –634 G/G, and –1154 A/A and G/A genotype (from translation start site) in the VEGF gene were linked with low VEGF protein expression in non-small cell lung cancer (NSCLC). They indicate that inherited variations in VEGF sequence, that also characterize the tumor genome, are determinants of the molecular VEGF phenotype in NSCLC and, consequently, of the intratumoral vascular density. Sample size, however, was small (36 cases) and VEGF –460T > C, +405G > C, and +936C> T polymorphisms were not evaluated in their study. Accordingly, further studies are needed to elucidate the relationship between the VEGF gene polymorphisms and serum VEGF level or VEGF protein expression.
Recently, several VEGF inhibitors, including bevacizumab, a monoclonal antibody against VEGF, have actively progressed into clinical trials for different tumor types, and the results are very encouraging [34]. Thus, if the prediction of individual angiogenic potential on the basis of VEGF genotypes is possible, the efficacy of antiangiogenic treatment could be further enhanced.
In conclusion, VEGF gene polymorphisms were found to be an independent prognostic marker for Korean patients with surgically resected gastric adenocarcinoma. Consequently, in addition to the pathologic stage, the analysis of VEGF gene polymorphisms may help identify patient subgroups at high risk for a poor disease outcome, thereby helping to refine therapeutic decisions in gastric cancer.
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This work was supported by BioMedical Research Institute grant, Kyungpook National University Hospital (2005). This work was presented at the 42nd Annual Meeting of the American Society of Clinical Oncology, Atlanta, GA, June 2–6, 2006.
Received for publication October 24, 2006. Revision received December 23, 2006. Accepted for publication February 8, 2007.
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1. Kim JP, Hur YS, Choe KJ, et al. Clinical analysis of 1136 early gastric cancers. Cancer Res Treat (1993) 25:808–818.
2. Parkin DM. Global cancer statistics in the year 2000. Lancet Oncol (2001) 2:533–543.[CrossRef][Web of Science][Medline]
3. Yancopoule GD, Davis S, Gale NW, et al. Vascular-specific growth factors and blood vessel formation. Nature (2000) 407:242–248.[CrossRef][Medline]
4. Carmeliet P, Jain RK. Angiogenesis in cancer and other disease. Nature (2000) 407:249–257.[CrossRef][Medline]
5. Toi M, Matsumoto T, Bando H. Vascular endothelial growth factor: its prognostic, predictive, and therapeutic implications. Lancet Oncol (2001) 2:667–673.[CrossRef][Web of Science][Medline]
6. Masuya D, Huang C-H, Liu D, et al. The intratumoral expression of vascular endothelial growth factor and interleukin-8 asscociated with angiogenesis in nonsmall cell lung carcinoma patients. Cancer (2001) 92:2628–2638.[CrossRef][Web of Science][Medline]
7. Fontanini G, Faviana P, Lucchi M, et al. A high vascular count and overexpression of vascular growth factor are associated with unfavorable prognosis in operated small cell lung cancer. Br J Cancer (2002) 86:558–563.[CrossRef][Web of Science][Medline]
8. Nishida N, Yano H, Komai K, et al. Vascular endothelial growth factor C and vascular endothelial growth factor receptor 2 are related closely to the prognosis of patients with ovarian carcinoma. Cancer (2004) 101:1364–1374.[CrossRef][Web of Science][Medline]
9. Stacker SA, Achen MG, Jussila L, et al. Lymphangiogenesis and cancer metastasis. Nat Rev Cancer (2002) 2:573–583.[CrossRef][Web of Science][Medline]
10. Ichikura T, Tomimatsu S, Ohkura E, et al. Prognostic significance of the expression of vascular endothelial growth factor (VEGF) and VEGF-C in gastric carcinoma. J Surg Oncol (2001) 78:132–137.[CrossRef][Web of Science][Medline]
11. Yonemura Y, Endo Y, Fujita H, et al. Role of vascular endothelial growth factor C expression in the development of lymph node metastasis in gastric cancer. Clin Cancer Res (1999) 5:1823–1829.
12. Juttner S, Wissmann C, Jons T, et al. Vascular endothelial growth factor-D and its receptor VEGFR-3: two novel independent prognostic markers in gastric adenocarcinoma. J Clin Oncol (2006) 24:228–240.
13. Mattei MG, Borg JP, Rosnet O, et al. Assignment of vascular endothelial growth factor (VEGF) and placenta growth factor (PIGF) genes to human chromosome 6p12-p21 and 14q24-q31 regions, respectively. Genomics (1996) 31:168–169.
14. Tischer E, Mitchell R, Hartman T, et al. The human gene for vascular endothelial growth factor: multiple protein forms are encoded through alternative exon splicing. J Biol Chem (1991) 266:11947–11954.
15. Watson CJ, Webb NJA, Bottomley MJ, Brenchley PEC. Identification of polymorphisms within the vascular endothelial growth factor (VEGF) gene: correlation with variation in VEGF protein production. Cytokine (2000) 12:1230–1235.
16. Renner W, Kotschan S, Hoffman C, et al. A common 936C/T mutation in the gene for vascular endothelial growth factor is associated with vascular endothelial factor plasma levels. J Vasc Res (2000) 37:443–448.[CrossRef][Web of Science][Medline]
17. Stevens A, Soden J, Brenchley PE, et al. Haplotype analysis of the polymorphic human vascular endothelial growth factor gene promoter. Cancer Res (2003) 63:812–816.
18. Howell WM, Bateman AC, Turner SJ, et al. Influence of vascular endothelial growth factor single nucleotide polymorphisms on tumor development in cutaneous malignant melanoma. Genes Immun (2002) 3:229–232.[CrossRef][Web of Science][Medline]
19. Lee SJ, Lee SY, Jeon HS, et al. Vascular endothelial growth factor gene polymorphisms and risk of primary lung cancer. Cancer Epidemiol Biomarkers Prev (2005) 14:571–575.
20. Lin CC, Wu HC, Tsai FJ, et al. Vascular endothelial growth factor gene –460C/T polymorphism is a biomarker for prostate cancer. Urology (2003) 62:374–377.[CrossRef][Web of Science][Medline]
21. Krippl P, Langsenlehner U, Renner W, et al. A common 936 C/T gene polymorphism of vascular endothelial growth factor is associated with decreased breast cancer. Int J Cancer (2003) 106:468–471.[CrossRef][Web of Science][Medline]
22. Ruzzo A, Graziano F, Kawakami K, et al. Pharmacogenetic profiling and clinical outcome of patients with advanced gastric cancer treated with with palliative chemotherapy. J Clin Oncol (2006) 24:1883–1891.
23. Lu H, Shu X, Cui Y, et al. Association of genetic polymorphisms in the VEGF gene with breast cancer survival. Cancer Res (2005) 65:5015–5019.
24. Jin Q, Hemminki K, Enquist K, et al. Vascular endothelial growth factor polymorphisms in relation to breast cancer development and prognosis. Clin Cancer Res (2005) 11:3647–3653.
25. Dotor E, Cuatrecases M, Martinez-Iniesta M, et al. Tumor thymidylate synthase 1496del6 genotype as a prognostic factor in colorectal cancer patients receiving flourouracil-based adjuvant treatment. J Clin Oncol (2006) 24:1603–1611.
26. Li D, Frazier M, Evans DB, et al. Single nucleotide polymorphisms of RecQ1, RAD54L, and ATM genes are associated with reduced survival of pancreatic cancer. J Clin Oncol (2006) 24:1720–1728.
27. Hamilton SR, Aaltonen LA. WHO Classification. In: Tumours of the Digestive System: Pathology & Genetics (2000) Lyon, France. IARC Press.
28. Greene FL, Page DL, Fleming ID, et al. The AJCC cancer staging manual (2002) 6th edition. New York, NY: Springer-Verlag.
29. Stephens M, Smith MJ, Donnelly P. A new statistical method for haplotype reconstruction from population data. Am J Hum Genet (2001) 68:978–989.[CrossRef][Web of Science][Medline]
30. Gonzalez CA, Sala N, Capella G. Genetic susceptibility and gastric cancer risk. Int J Cancer (2002) 100:249–260.[CrossRef][Web of Science][Medline]
31. Karayiannakis AJ, Syrigos KN, Polychronidis A, et al. Circulating VEGF levels in the serum of gastric cancer patients. Ann Surg (2002) 236:37–42.[CrossRef][Web of Science][Medline]
32. Awata T, Inoue K, Kurihara S, et al. A common polymorphism in the 5'-untranslated region of the VEGF gene is associated with diabetic retinopathy in type 2 diabetes. Diabetes (2002) 51:1630–1635.
33. Koukourakis MI, Papazoglou D, Giatromanolaki A, et al. VEGF gene sequence variation defines VEGF gene expression status and angiogenic activity in non-small cell lung cancer. Lung Cancer (2004) 46:293–298.[CrossRef][Web of Science][Medline]
34. Hurwitz H, Fehrenbacher L, Novotny W, et al. Bevacizumab plus irinotecan, fluorouracil, and leucovorin for metastatic colorectal cancer. N Engl J Med (2004) 350:2335–2342.
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 |
|
 G. Lurje, W. Zhang, A. M. Schultheis, D. Yang, S. Groshen, A. E. Hendifar, H. Husain, M. A. Gordon, F. Nagashima, H. M. Chang, et al. Polymorphisms in VEGF and IL-8 predict tumor recurrence in stage III colon cancer Ann. Onc., October 1, 2008; 19(10): 1734 - 1741. [Abstract] [Full Text] [PDF]
|
|
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J. G. Kim, Y. S. Chae, S. K. Sohn, Y. Y. Cho, J. H. Moon, J. Y. Park, S. W. Jeon, I. T. Lee, G. S. Choi, and S.-H. Jun Vascular Endothelial Growth Factor Gene Polymorphisms Associated with Prognosis for Patients with Colorectal Cancer Clin. Cancer Res., January 1, 2008; 14(1): 62 - 66. [Abstract] [Full Text] [PDF]
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