RESUMO
BACKGROUND: Genetic susceptibility plays an important role in the risk of developing pain in individuals with cancer. As a complex trait, multiple genes underlie this susceptibility. We used gene network analyses to identify novel target genes associated with pain in patients newly diagnosed with squamous cell carcinoma of the head and neck (HNSCC). RESULTS: We first identified 36 cancer pain-related genes (i.e., focus genes) from 36 publications based on a literature search. The Ingenuity Pathway Analysis (IPA) analysis identified additional genes that are functionally related to the 36 focus genes through pathway relationships yielding a total of 82 genes. Subsequently, 800 SNPs within the 82 IPA-selected genes on the Illumina HumanOmniExpress-12v1 platform were selected from a large-scale genotyping effort. Association analyses between the 800 candidate SNPs (covering 82 genes) and pain in a patient cohort of 1368 patients with HNSCC (206 patients with severe pain vs. 1162 with non-severe pain) showed the highest significance for MAPK1/ERK2, a gene belonging to the MAP kinase family (rs8136867, p value = 8.92 × 10(-4); odds ratio [OR] = 1.33, 95 % confidence interval [CI]: 1.13-1.58). Other top genes were PIK3C2G (a member of PI3K [complex], rs10770367, p value = 1.10 × 10(-3); OR = 1.46, 95 % CI: 1.16-1.82), TCRA (the alpha chain of T-cell receptor, rs6572493, p value = 2.84 × 10(-3); OR = 0.70, 95 % CI: 0.55-0.88), PDGFC (platelet-derived growth factor C, rs6845322, p value = 4.88 × 10(-3); OR = 1.32, 95 % CI: 1.09-1.60), and CD247 (a member of CD3, rs2995082, p value = 7.79 × 10(-3); OR = 0.76, 95 % CI: 0.62-0.93). CONCLUSIONS: Our findings provide novel candidate genes and biological pathways underlying pain in cancer patients. Further study of the variations of these candidate genes could inform clinical decision making when treating cancer pain.
Assuntos
Carcinoma de Células Escamosas/genética , Terapia Genética , Neoplasias de Cabeça e Pescoço/genética , Proteína Quinase 1 Ativada por Mitógeno/genética , Dor/genética , Idoso , Carcinoma de Células Escamosas/terapia , Estudos de Casos e Controles , Feminino , Predisposição Genética para Doença , Técnicas de Genotipagem , Neoplasias de Cabeça e Pescoço/terapia , Humanos , Linfocinas/genética , Masculino , Pessoa de Meia-Idade , Fenótipo , Fosfatidilinositol 3-Quinases/genética , Fator de Crescimento Derivado de Plaquetas/genética , Polimorfismo de Nucleotídeo Único , Carcinoma de Células Escamosas de Cabeça e PescoçoRESUMO
Pain is often one of the first signs of squamous cell carcinoma of the head and neck (HNSCC). Pain at diagnosis is an important prognostic marker for the development of chronic pain, and importantly, for the overall survival time. To identify variants influencing severe pre-treatment pain in 1,368 patients newly diagnosed with HNSCC, we conducted a genome-wide association study based on 730,525 tagging SNPs. The patients were all previously untreated for cancer. About 15% of the patients had severe pre-treatment pain, defined as pain score ≥7 (0 = "no pain" and 10 = "worst pain"). We identified 3 common genetic variants in high linkage disequilibrium for severe pre-treatment pain, representing one genomic region at 1q44 (rs3862188, P = 3.45 × 10-8; rs880143, P = 3.45 × 10-8; and rs7526880, P = 4.92 × 10-8), which maps to the RP11-634B7.4 gene, a novel antisense gene to three olfactory receptor genes. Olfactory receptor genes, upstream effectors of the MAPK signaling cascade, might be novel target genes for pain in HNSCC patients. Future experimental validation to explore biological mechanisms will be key to defining the role of the intronic variants and non-coding RNA for pain in patients with HNSCC.