Browsing by Author "Miquel, Juan Francisco"
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Item A case-control study of a combination of single nucleotide polymorphisms and clinical parameters to predict clinically relevant toxicity associated with fluoropyrimidine and platinum-based chemotherapy in gastric cancer(2021) Cordova-Delgado, Miguel; Bravo, María Loreto; Cumsille, Elisa; Hill, Charlotte N.; Muñoz-Medel, Matías; Pinto, Mauricio P.; Retamal, Ignacio N.; Lavanderos, María A.; Miquel, Juan Francisco; Rodriguez-Fernandez, Maria; Liao, Yuwei; Li, Zhiguang; Corvalán, Alejandro H.; Armisén, Ricardo; Garrido, Marcelo; Quiñones, Luis A.; Owen, Gareth I.Background: Fluoropyrimidine plus platinum chemotherapy remains the standard first line treatment for gastric cancer (GC). Guidelines exist for the clinical interpretation of four DPYD genotypes related to severe fluoropyrimidine toxicity within European populations. However, the frequency of these single nucleotide polymorphisms (SNPs) in the Latin American population is low (< 0.7%). No guidelines have been development for platinum. Herein, we present association between clinical factors and common SNPs in the development of grade 3–4 toxicity. Methods: Retrospectively, 224 clinical records of GC patient were screened, of which 93 patients were incorporated into the study. Eleven SNPs with minor allelic frequency above 5% in GSTP1, ERCC2, ERCC1, TP53, UMPS, SHMT1, MTHFR, ABCC2 and DPYD were assessed. Association between patient clinical characteristics and toxicity was estimated using logistic regression models and classification algorithms. Results: Reported grade ≤ 2 and 3–4 toxicities were 64.6% (61/93) and 34.4% (32/93) respectively. Selected DPYD SNPs were associated with higher toxicity (rs1801265; OR = 4.20; 95% CI = 1.70–10.95, p = 0.002), while others displayed a trend towards lower toxicity (rs1801159; OR = 0.45; 95% CI = 0.19–1.08; p = 0.071). Combination of paired SNPs demonstrated significant associations in DPYD (rs1801265), UMPS (rs1801019), ABCC2 (rs717620) and SHMT1 (rs1979277). Using multivariate logistic regression that combined age, sex, peri-operative chemotherapy, 5-FU regimen, the binary combination of the SNPs DPYD (rs1801265) + ABCC2 (rs717620), and DPYD (rs1801159) displayed the best predictive performance. A nomogram was constructed to assess the risk of developing overall toxicity. Conclusion: Pending further validation, this model could predict chemotherapy associated toxicity and improve GC patient quality of life.Item A Single-Nucleotide Polymorphism of αVβ3 Integrin Is Associated with the Andes Virus Infection Susceptibility(2019) Martínez-Valdebenito, Constanza; Angulo, Jenniffer; Corre, Nicole Le; Marco, Claudia; Vial, Cecilia; Miquel, Juan Francisco; Cerda, Jaime; Mertz, Gregory; Vial, Pablo; Lopez-Lastra, Marcelo; Ferrés, MarcelaThe Andes Orthohantavirus (ANDV), which causes the hantavirus cardiopulmonary syndrome, enters cells via integrins, and a change from leucine to proline at residue 33 in the PSI domain (L33P), impairs ANDV recognition. We assessed the association between this human polymorphism and ANDV infection. We defined susceptible and protective genotypes as “TT” (coding leucine) and “CC” (coding proline), respectively. TT was present at a rate of 89.2% (66/74) among the first cohort of ANDV cases and at 60% (63/105) among exposed close-household contacts, who remained uninfected (p < 0.05). The protective genotype (CC) was absent in all 85 ANDV cases, in both cohorts, and was present at 11.4% of the exposed close-household contacts who remained uninfected. Logistic regression modeling for risk of infection had an OR of 6.2–12.6 (p < 0.05) in the presence of TT and well-known ANDV risk activities. Moreover, an OR of 7.3 was obtained when the TT condition was analyzed for two groups exposed to the same environmental risk. Host genetic background was found to have an important role in ANDV infection susceptibility, in the studied population.Item Evaluation of the chemopreventive potentials of ezetimibeand aspirin in a novel mouse model of gallbladderpreneoplasia(2020) Rosa, Lorena; Lobos-González, Lorena; Munoz Durango, Natalia; Garcıa, Patricia; Bizama, Carolina; Gomez, Natalia; Gonzalez, Ximena; Wichmann, Ignacio A.; Saavedra, Nicolas; Guevara, Francisca; Villegas, Jaime; Arrese, Marco; Ferreccio, Catterina; Alexis M. Kalergis, Alexis M.; Miquel, Juan Francisco; Espinoza, Jaime A.; Roa, Juan C.Gallbladder stones (cholecystolithiasis) are the main risk factor for gallbladder cancer (GBC), a lethal biliary malignancy with poor survival rates worldwide. Gallbladder stones are thought to damage the gallbladder epithelium and trigger chronic inflammation. Preneoplastic lesions that arise in such an inflammatory microenvironment can eventually develop into invasive carcinoma, through mechanisms that are not fully understood. Here, we developed a novel gallbladder preneoplasia mouse model through the administration of two lithogenic diets (a low- or a high-cholesterol diet) in wild-type C57BL/6 mice over a period of 9 months. Additionally, we evaluated the chemopreventive potentials of the anti-inflammatory drug aspirin and the cholesterol absorption inhibitor ezetimibe. Both lithogenic diets induced early formation of gallbladder stones, together with extensive inflammatory changes and widespread induction of metaplasia, an epithelial adaptation to tissue injury. Dysplastic lesions were presented only in mice fed with high-cholesterol diet (62.5%) in late stages (9th month), and no invasive carcinoma was observed at any stage. The cholesterol absorption inhibitor ezetimibe inhibited gallbladder stone formation and completely prevented the onset of metaplasia and dysplasia in both lithogenic diets, whereas aspirin partially reduced metaplasia development only in the low-cholesterol diet setting. This model recapitulates several of the structural and inflammatory findings observed in human cholecystolithiasic gallbladders, making it relevant for the study of gallbladder carcinogenesis. In addition, our results suggest that the use of cholesterol absorption inhibitors and anti-inflammatory drugs can be evaluated as chemopreventive strategies to reduce the burden of GBC among high-risk populations.