Abstract
BACKGROUND:
Colorectal cancer is a serious disease that causes significant morbidity and mortality in developed countries. Genetic changes, such as mutations in proto-oncogenes and DNA repair genes, and loss of function in the tumor suppressor genes cause colorectal cancer development. Abnormal DNA methylation is also known to play a crucial role in colorectal carcinogenesis.
OBJECTIVE:
In this study, frequencies of KRAS and BRAF mutations, promoter hypermethylation profiles of SFRP2, DAPK1, MGMT, HIC1 and p16 genes, and possible associations between hypermethylation of these genes and KRAS and BRAF mutations were aimed to find out.
METHODS:
Ninety three colorectal cancer tissues and 14 normal colon mucosas were included in the study. Common twelve KRAS gene mutation were investigated with using reverse-hybridization strip assay method. BRAF V600E mutations were investigated with RFLP method. Hypermethylation status of five tumor suppressor genes were detected by using reverse-hybridization strip assay method after bisulfite modification of DNA.
RESULTS:
KRAS and BRAF mutation frequencies were determined as 54.84% and 12.9%, respectively. Promoter hypermethylation frequencies of tumor suppressor genes SFRP2, DAPK1, MGMT, HIC1 and p16 were determined as 66.7%, 45.2%, 40.9%, 40.9% and 15.1%, respectively. Statistically significant associations were found between BRAF mutation and SFRP2 and p16 tumor suppressor genes hypermethylation (SFRP2; p= 0.005, p16; p= 0.016). Compared to rectum, SFRP2 (p= 0.017) and MGMT (p= 0.013) genes have statistically significantly higher promoter hypermethylation in colon.
CONCLUSIONS:
Results of the current study have confirmed that KRAS mutations and SFRP2 hypermethylation can be used as genetic markers in colorectal cancer.
Keywords: Colorectal cancer, hypermethylation, oncogene, tumor suppressor gene, KRAS, BRAF, SFRP2, DAPK1, MGMT, HIC1, p16
Full Text
The Full Text of this article is available as a PDF (321.5 KB).
References
- [1]. Adjei AA Blocking oncogenic Ras signaling for cancer therapy. J Natl Cancer Inst 2001; 93(14): 1062-1074. [DOI] [PubMed] [Google Scholar]
- [2]. Ahuja N, Mohan AL, Li Q, et al. Association between CpG island methylation and microsatellite instability in colorectal cancer. Cancer Res 1997; 57(16): 3370-3374. [PubMed] [Google Scholar]
- [3]. Al-Mulla F, Going JJ, Sowden ET, Winter A, Pickford IR, Birnie GD. Heterogeneity of mutant versus wild-type Ki-ras in primary and metastatic colorectal carcinomas, and association of codon-12 valine with early mortality. J Pathol 1998; 185(2): 130-138. [DOI] [PubMed] [Google Scholar]
- [4]. Andreyev HJ, Norman AR, Cunningham D, et al. Kirsten ras mutations in patients with colorectal cancer: the 'RASCAL II' study. Br J Cancer 2001; 85(5): 692-696. [DOI] [PMC free article] [PubMed] [Google Scholar]
- [5]. Anjum R, Roux PP, Ballif BA, Gygi SP, Blenis J. The tumor suppressor DAP kinase is a target of RSK-mediated survival signaling. Curr Biol 2005; 15(19): 1762-1767. [DOI] [PubMed] [Google Scholar]
- [6]. Arrington AK, Heinrich EL, Lee W, et al. Prognostic and predictive roles of KRAS mutation in colorectal cancer. Int J Mol Sci 2012; 13(10): 12153-13168. [DOI] [PMC free article] [PubMed] [Google Scholar]
- [7]. Arslan S, Akkurt I, Koksal B, Karadayi S, Ozdemir O. Predictive significance of KRAS point mutation in patients with non-small cell lung carcinoma relation to smoking and asbestos exposure in middle Anatolia population. Healthmed 2010; 4: 715-719. [Google Scholar]
- [8]. Arslan S, Dogan T, Koksal B, et al. Tumoral tissue specific promoter hypermethylation of distinct tumor suppressor genes in a case with nonsmall cell lung carcinoma: A case report. Lung India 2008; 25(4): 148-151. [DOI] [PMC free article] [PubMed] [Google Scholar]
- [9]. Berg M, Danielsen SA, Ahlquist T, et al. DNA sequence profiles of the colorectal cancer critical gene set KRAS-BRAF-PIK3CA-PTEN-TP53 related to age at disease onset. PLoS ONE 2010; 5(11): e13978. [DOI] [PMC free article] [PubMed] [Google Scholar]
- [10]. Brink M, de Goeij AF, Weijenberg MP, et al. K-ras oncogene mutations in sporadic colorectal cancer in The Netherlands Cohort Study. Carcinogenesis 2003; 24(4): 703-710. [DOI] [PubMed] [Google Scholar]
- [11]. Chang SC, Lin JK, Yang SH, Wang HS, Li AF, Chi CW. Relationship between genetic alterations and prognosis in sporadic colorectal cancer. Int J Cancer 2006; 118(7): 1721-1727. [DOI] [PubMed] [Google Scholar]
- [12]. Dahabreh IJ, Terasawa T, Castaldi PJ, Trikalinos TA. Systematic review: Anti-epidermal growth factor receptor treatment effect modification by KRAS mutations in advanced colorectal cancer. Ann Intern Med 2011; 154(1): 37-49. [DOI] [PubMed] [Google Scholar]
- [13]. Deng G, Bell I, Crawley S, et al. BRAF mutation is frequently present in sporadic colorectal cancer with methylated hMLH1, but not in hereditary nonpolyposis colorectal cancer. Clin Cancer Res 2004; 10: 191-195. [DOI] [PubMed] [Google Scholar]
- [14]. de Vogel S, Weijenberg MP, Herman JG, et al. MGMT and MLH1 promoter methylation versus APC, KRAS and BRAF gene mutations in colorectal cancer: Indications for distinct pathways and sequence of events. Ann Oncol 2009;. 20(7): 1216-1222. [DOI] [PubMed] [Google Scholar]
- [15]. Diehl JA, Zindy F, Sherr CJ. Inhibition of cyclin D1 phosphorylation on threonine-286 prevents its rapid degradation via the ubiquitin-proteasome pathway. Genes Dev 1997; 11(8): 957-972. [DOI] [PubMed] [Google Scholar]
- [16]. Di Nicolantonio F, Martini M, Molinari F, et al. Wild-type BRAF is required for response to panitumumab or cetuximab in metastatic colorectal cancer. J Clin Oncol 2008; 26(35): 5705-5712. [DOI] [PubMed] [Google Scholar]
- [17]. Dong SM, Lee EJ, Jeon ES, Park CK, Kim KM. Progressive methylation during the serrated neoplasia pathway of the colorectum. Mod Pathol 2004; 18(2): 170-178. [DOI] [PubMed] [Google Scholar]
- [18]. Esteller M, Toyota M, Sanchez-Cespedes M, et al. Inactivation of the DNA repair gene O6-methylguanine-DNA methyltransferase by promoter hypermethylation is associated with G to A mutations in K-ras in colorectal tumorigenesis. Cancer Res 2000; 60(9): 2368-2371. [PubMed] [Google Scholar]
- [19]. Guan RJ, Fu Y, Holt PR, Pardee AB. Association of K-ras mutations with p16 methylation in human colon cancer. Gastroenterology 1999; 116(5): 1063-1071. [DOI] [PubMed] [Google Scholar]
- [20]. Hawkins NJ, Lee JH, Wong JJ, Kwok CT, Ward RL, Hitchins MP. MGMT methylation is associated primarily with the germline C>T SNP (rs16906252) in colorectal cancer and normal colonic mucosa. Mod Pathol 2009; 22(12): 1588-1599. [DOI] [PubMed] [Google Scholar]
- [21]. Heinemann V, Stintzing S, Kirchner T, Boeck S, Jung A. Clinical relevance of EGFR- and KRAS-status in colorectal cancer patients treated with monoclonal antibodies directed against the EGFR. Cancer Treat Rev 2009; 35(3): 62-267. [DOI] [PubMed] [Google Scholar]
- [22]. Huang Z, Li L, Wang J. Hypermethylation of SFRP2 as a potential marker for stool-based detection of colorectal cancer and precancerous lesions. Dig Dis Sci 2007; 52(9): 2287-2291. [DOI] [PubMed] [Google Scholar]
- [23]. Imamura Y, Morikawa T, Liao X, et al. Specific mutations in KRAS codons 12 and 13, and patient prognosis in 1075 BRAF wild-type colorectal cancers. Clin Cancer Res 2012; 18(17): 4753-4763. [DOI] [PMC free article] [PubMed] [Google Scholar]
- [24]. Issa JP. Aging, DNA methylation and cancer. Crit Rev Oncol Hematol 1999; 32(1): 31-43. [DOI] [PubMed] [Google Scholar]
- [25]. Kawakami K, Ruszkiewicz A, Bennett G, et al. DNA hypermethylation in the normal colonic mucosa of patients with colorectal cancer. Br J Cancer 2006; 94(4): 593-598. [DOI] [PMC free article] [PubMed] [Google Scholar]
- [26]. Lee M, Han WS, Kim OK, et al. Prognostic value of p16INK4a and p14ARF gene hypermethylation in human colon cancer. Pathol Res Pract 2006;. 202(6): 415-424. [DOI] [PubMed] [Google Scholar]
- [27]. Li HT, Lu YY, An YX, Wang X, Zhao QC. KRAS, BRAF and PIK3CA mutations in human colorectal cancer: Relationship with metastatic colorectal cancer. Oncol Rep 2011; 25(6): 1691-1697. [DOI] [PubMed] [Google Scholar]
- [28]. Liggett WH, Sidransky D. Role of the p16 tumor suppressor gene in cancer. J Clin Oncol 1998; 16(3): 1197-1206. [DOI] [PubMed] [Google Scholar]
- [29]. Minoo P, Baker K, Goswami R, et al. Extensive DNA methylation in normal colorectal mucosa in hyperplastic polyposis. Gut 2006; 55(10): 1467-1474. [DOI] [PMC free article] [PubMed] [Google Scholar]
- [30]. Moerkerk P, Arends JW, van Driel M, de Bruïne A, de Goeij A, ten Kate J. Type and number of Ki-ras point mutations relate to stage of human colorectal cancer. Cancer Res 1994; 54(13): 3376-3378. [PubMed] [Google Scholar]
- [31]. Morton RF, Hammond EH. ASCO Provisional Clinical Opinion: KRAS, Cetuximab, and Panitumumab-Clinical Implications in Colorectal Cancer. J Oncol Pract 2009; 5(2): 71-72. [DOI] [PMC free article] [PubMed] [Google Scholar]
- [32]. Namba H, Nakashima M, Hayashi T, et al. Clinical implication of hot spot BRAF mutation, V599E, in papillary thyroid cancers. J Clin Endocrinol Metab 2003; 88(9): 4393-4397. [DOI] [PubMed] [Google Scholar]
- [33]. Nash GM, Gimbel M, Shia J, et al. KRAS mutation correlates with accelerated metastatic progression in patients with colorectal liver metastases. Ann Surg Oncol 2010; 17(2): 572-578. [DOI] [PubMed] [Google Scholar]
- [34]. Nicoll G, Crichton DN, McDowell HE, Kernohan N, Hup TR, Thompson AM. Expression of the Hypermethylated in Cancer gene (HIC-1) is associated with good outcome in human breast cancer. Br J Cancer 2001; 85(12): 1878-1882. [DOI] [PMC free article] [PubMed] [Google Scholar]
- [35]. Nosho K, Irahara N, Shima K, et al. Comprehensive biostatistical analysis of CpG island methylator phenotype in colorectal cancer using a large population-based sample. PLoS ONE 2008; 3(11): e3698. [DOI] [PMC free article] [PubMed] [Google Scholar]
- [36]. Ogino S, Meyerhardt JA, Irahara N, et al. KRAS mutation in stage III colon cancer and clinical outcome following intergroup trial CALGB 89803. Clin Cancer Res 2009; 15(23): 7322-7329. [DOI] [PMC free article] [PubMed] [Google Scholar]
- [37]. Rajagopalan H, Bardelli A, Lengauer C, Kinzler KW, Vogelstein B, Velculescu VE. Tumorigenesis: RAF/RAS oncogenes and mismatch-repair status. Nature 2002; 418(6901): 934. [DOI] [PubMed] [Google Scholar]
- [38]. Rattner A, Hsieh JC, Smallwood PM, et al. A family of secreted proteins contains homology to the cysteine-rich ligand-binding domain of frizzled receptors. PNAS 1997; 94(7): 2859-2863. [DOI] [PMC free article] [PubMed] [Google Scholar]
- [39]. Richman SD, Seymour MT, Chambers P, et al. KRAS and BRAF mutations in advanced colorectal cancer are associated with poor prognosis but do not preclude benefit from oxaliplatin or irinotecan: results from the MRC FOCUS trial. J Clin Oncol 2009; 27(35): 5931-5937. [DOI] [PubMed] [Google Scholar]
- [40]. Samowitz WS, Curtin K, Schaffer D, Robertson M, Leppert M, Slattery ML. Relationship of Ki-ras mutations in colon cancers to tumor location, stage, and survival: a population-based study. Cancer Epidemiol Biomarkers Pre 2000; 9(11): 1193-1197. [PubMed] [Google Scholar]
- [41]. Shannon BA, Iacopetta BJ. Methylation of the hMLH1, p16, and MDR1 genes in colorectal carcinoma: associations with clinicopathological features. Cancer Letters 2001; 167(1): 91-97. [DOI] [PubMed] [Google Scholar]
- [42]. Shen L, Kondo Y, Rosner GL, et al. MGMT promoter methylation and field defect in sporadic colorectal cancer. J Natl Cancer Inst 2005; 97(18): 1330-1338. [DOI] [PubMed] [Google Scholar]
- [43]. Shiloh R, Bialik S, Kimchi A. The DAPK family: A structure-function analysis. Apoptosis 2014;. 19(2): 286-297. [DOI] [PubMed] [Google Scholar]
- [44]. Siegel R, DeSantis C, Jemal A. Colorectal cancer statistics, 2014. CA: A cancer journal for clinicians 2014; 64(2): 104-117. [DOI] [PubMed] [Google Scholar]
- [45]. Siena S, Sartore-Bianchi A, Di Nicolantonio F, Balfour J, Bardelli A. Biomarkers predicting clinical outcome of epidermal growth factor receptor-targeted therapy in metastatic colorectal cancer. J Natl Cancer Inst 2009; 101(19): 1308-1324. [DOI] [PMC free article] [PubMed] [Google Scholar]
- [46]. Smith G, Bounds R, Wolf H, Steele RJC, Carey FA, Wolf CR. Activating K-Ras mutations outwith `hotspot' codons in sporadic colorectal tumours-implications for personalised cancer medicine. Br J Cancer 2010; 102(4): 693-703. [DOI] [PMC free article] [PubMed] [Google Scholar]
- [47]. Sui C, Wang G, Chen Q, Ma J. Variation risks of SFRP2 hypermethylation between precancerous disease and colorectal cancer. Tumor Biology 2014; 35(10): 10457-10465. [DOI] [PubMed] [Google Scholar]
- [48]. Suzuki H, Watkins DN, Jair KW, et al. Epigenetic inactivation of SFRP genes allows constitutive WNT signaling in colorectal cancer. Nat Genet 2004; 36(4): 417-422. [DOI] [PubMed] [Google Scholar]
- [49]. Sweeney C, Boucher KM, Samowitz WS, et al. Oncogenetic tree model of somatic mutations and DNA methylation in colon tumors. Genes, Chromosomes and Cancer 2009; 48(1): 1-9. [DOI] [PMC free article] [PubMed] [Google Scholar]
- [50]. Tanaka N, Huttenhower C, Nosho K, et al. Novel application of structural equation modeling to correlation structure analysis of CpG island methylation in colorectal cancer. Am J Pathol 2010; 177(6): 2731-2740. [DOI] [PMC free article] [PubMed] [Google Scholar]
- [51]. Tol J, Punt CJ. Monoclonal antibodies in the treatment of metastatic colorectal cancer: A review. Clin Ther 2010; 32(3): 437-453. [DOI] [PubMed] [Google Scholar]
- [52]. Van Cutsem E, Köhne CH, Láng I, et al. Cetuximab Plus Irinotecan, Fluorouracil, and Leucovorin As First-Line Treatment for Metastatic Colorectal Cancer: Updated Analysis of Overall Survival According to Tumor KRAS and BRAF Mutation Status. J Clin Oncol 2011; 29(15): 2011-2019. [DOI] [PubMed] [Google Scholar]
- [53]. Wang DR, Tang D. Hypermethylated SFRP2 gene in fecal DNA is a high potential biomarker for colorectal cancer noninvasive screening. World J Gastroenterol 2008; 14(4): 524-531. [DOI] [PMC free article] [PubMed] [Google Scholar]
- [54]. Wu CM, Tang R, Wang JY, Changchien CR, Hsieh LL. Frequency and spectrum of K-RAS codons 12 and 13 mutations in colorectal adenocarcinomas from Taiwan. ancer Genet Cytogenet 2005; 158(1): 55-60. [DOI] [PubMed] [Google Scholar]
- [55]. Yen LC, Uen YH, Wu DC, et al. Activating KRAS mutations and overexpression of epidermal growth factor receptor as independent predictors in metastatic colorectal cancer patients treated with cetuximab. Ann Surg 2010; 251(2): 254-260. [DOI] [PubMed] [Google Scholar]
- [56]. Yokota T, Ura T, Shibata N, et al. BRAF mutation is a powerful prognostic factor in advanced and recurrent colorectal cancer. Br J Cancer 2011; 104(5): 856-862. [DOI] [PMC free article] [PubMed] [Google Scholar]
