Browsing by Author "El Charif, Omar"

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    Clinical and Genetic Risk Factors for Radiation-Associated Ototoxicity: A Report from the Childhood Cancer Survivor Study and the St. Jude Lifetime Cohort
    (Wiley, 2021) Trendowski, Matthew R.; Baedke, Jessica L.; Sapkota, Yadav; Travis, Lois B.; Zhang, Xindi; El Charif, Omar; Wheeler, Heather E.; Leisenring, Wendy M.; Robison, Leslie L.; Hudson, Melissa M.; Morton, Lindsay M.; Oeffinger, Kevin C.; Howell, Rebecca M.; Armstrong, Gregory T.; Bhatia, Smita; Dolan, M. Eileen; Epidemiology, School of Public Health
    Background: Cranial radiation therapy (CRT) is associated with ototoxicity, which manifests as hearing loss and tinnitus. The authors sought to identify clinical determinants and genetic risk factors for ototoxicity among adult survivors of pediatric cancer treated with CRT. Methods: Logistic regression evaluated associations of tinnitus (n = 1991) and hearing loss (n = 2198) with nongenetic risk factors and comorbidities among CRT-treated survivors in the Childhood Cancer Survivor Study. Genome-wide association studies (GWASs) of CRT-related tinnitus and hearing loss were also performed. Results: Males were more likely to report CRT-related tinnitus (9.4% vs 5.4%; P = 5.1 × 10-4 ) and hearing loss (14.0% vs 10.7%; P = .02) than females. Survivors with tinnitus or hearing loss were more likely to experience persistent dizziness or vertigo (tinnitus: P < 2 × 10-16 ; hearing loss: P = 6.4 × 10-9 ), take antidepressants (tinnitus: P = .02; hearing loss: P = .01), and report poorer overall health (tinnitus: P = 1.5 × 10-6 ; hearing loss: P = 1.7 × 10-6 ) in comparison with controls. GWAS of CRT-related tinnitus revealed a genome-wide significant signal in chromosome 1 led by rs203248 (P = 1.5 × 10-9 ), whereas GWAS of CRT-related hearing loss identified rs332013 (P = 5.8 × 10-7 ) in chromosome 8 and rs67522722 (P = 7.8 × 10-7 ) in chromosome 6 as nearly genome-wide significant. A replication analysis identified rs67522722, intronic to ATXN1, as being significantly associated with CRT-related hearing loss (P = .03) and de novo hearing loss (P = 3.6 × 10-4 ). Conclusions: CRT-associated ototoxicity was associated with sex, several neuro-otological symptoms, increased antidepressant use, and poorer self-reported health. GWAS of CRT-related hearing loss identified rs67522722, which was supported in an independent cohort of survivors. Lay summary: Hearing loss and subjective tinnitus (the perception of noise or ringing in the ear) are long-term side effects of cancer treatment and are common in children treated with radiation to the brain. These toxicities can affect childhood development and potentially contribute to serious learning and behavioral difficulties. This study's data indicate that males are at greater risk for hearing loss and tinnitus than females after radiation therapy to the brain. Those who develop these toxicities are more likely to use antidepressants and report poorer overall health. Health care providers can improve the management of survivors by informing patients and/or their parents of these risks.
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    Clinical and Genome-Wide Analysis of Serum Platinum Levels after Cisplatin-Based Chemotherapy
    (American Association for Cancer Research, 2019-10-01) Trendowski, Matthew R.; El Charif, Omar; Ratain, Mark J.; Monahan, Patrick; Mu, Zepeng; Wheeler, Heather E.; Dinh, Paul C., Jr.; Feldman, Darren R.; Ardeshir-Rouhani-Fard, Shirin; Hamilton, Robert J.; Vaughn, David J.; Fung, Chunkit; Kollmannsberger, Christian; Mushiroda, Taisei; Kubo, Michiaki; Hannigan, Robyn; Strathmann, Frederick; Einhorn, Lawrence H.; Fossa, Sophie D.; Travis, Lois B.; Dolan, M. Eileen; Medicine, School of Medicine
    Purpose: Serum platinum is measurable for years after completion of cisplatin-based chemotherapy (CBC). We report the largest investigation of serum platinum levels to date of 1,010 testicular cancer survivors (TCS) assessed 1-35 years after CBC and evaluate genetic contributions to these levels. Experimental Design: Eligible TCS given 300 or 400 (±15) mg/m2 cisplatin underwent extensive audiometric testing, clinical examination, completed questionnaires and had crude serum platinum levels measured. Associations between serum platinum and various risk factors and toxicities were assessed after fitting a bi-exponential model adjusted for follow-up time and cumulative cisplatin dose. A genome-wide association study (GWAS) was performed using the serum platinum residuals of the dose and time-adjusted model. Results: Serum platinum levels exceeded the reference range for approximately 31 years, with a strong inverse relationship with creatinine clearance at follow-up (age-adjusted p = 2.13×10−3). We observed a significant, positive association between residual platinum values and luteinizing hormone (age-adjusted p=6.58×10−3). Patients with high residual platinum levels experienced greater Raynaud’s phenomenon than those with medium or low levels (age-adjusted ORhigh/low = 1.46; p = 0.04), as well as a higher likelihood of developing tinnitus (age-adjusted ORhigh/low = 1.68, p = 0.07). GWAS identified one single nucleotide polymorphism (SNP) meeting genome-wide significance rs1377817 (p=4.6×10−8, a SNP intronic to MYH14). Conclusions: This study indicates that residual platinum values are correlated with several cisplatin-related toxicities. One genetic variant is associated with these levels.
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    Genetic and Modifiable Risk Factors Contributing to Cisplatin-Induced Toxicities
    (American Association for Cancer Research, 2019-02-15) Trendowski, Matthew R.; El Charif, Omar; Dinh, Paul C. Jr.; Travis, Lois B.; Dolan, M.; Medicine, School of Medicine
    Effective administration of traditional cytotoxic chemotherapy is often limited by off-target toxicities. This clinical dilemma is epitomized by cisplatin, a platinating agent that has potent antineoplastic activity due to its affinity for DNA and other intracellular nucleophiles. Despite its efficacy against many adult-onset and pediatric malignancies, cisplatin elicits multiple off-target toxicities that can not only severely impact a patient’s quality of life, but also lead to dose reductions or the selection of alternative therapies that can ultimately affect outcomes. Without an effective therapeutic measure by which to successfully mitigate many of these symptoms, there have been attempts to identify a priori those individuals who are more susceptible to developing these sequelae through studies of genetic and nongenetic risk factors. Older age is associated with cisplatin induced ototoxicity, neurotoxicity and nephrotoxicity. Traditional genome-wide association studies have identified single nucleotide polymorphisms in ACYP2 and WFS1 associated with cisplatin-induced hearing loss. However, validating associations between specific genotypes and cisplatin-induced toxicities with enough stringency to warrant clinical application remains challenging. This review summarizes the current state of knowledge with regard to specific adverse sequelae following cisplatin-based therapy with a focus on ototoxicity, neurotoxicity, nephrotoxicity, myelosuppression and nausea/emesis. We discuss variables (genetic and nongenetic) contributing to these detrimental toxicities, and currently available means to prevent or treat their occurrence.
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    Variants in WFS1 and Other Mendelian Deafness Genes Are Associated with Cisplatin-Associated Ototoxicity
    (American Association for Cancer Research, 2017-07-01) Wheeler, Heather E.; Gamazon, Eric R.; Frisina, Robert D.; Perez-Cervantes, Carlos; El Charif, Omar; Mapes, Brandon; Fossa, Sophie D.; Feldman, Darren R.; Hamilton, Robert J.; Vaughn, David J.; Beard, Clair J.; Fung, Chunkit; Kollmannsberger, Christian; Kim, Jeri; Mushiroda, Taisei; Kubo, Michiaki; Ardeshir-Rouhani-Fard, Shirin; Einhorn, Lawrence; Cox, Nancy J.; Dolan, M. Eileen; Travis, Lois B.; Medicine, School of Medicine
    Purpose: Cisplatin is one of the most commonly used chemotherapy drugs worldwide and one of the most ototoxic. We sought to identify genetic variants that modulate cisplatin-associated ototoxicity (CAO).Experimental Design: We performed a genome-wide association study (GWAS) of CAO using quantitative audiometry (4-12 kHz) in 511 testicular cancer survivors of European genetic ancestry. We performed polygenic modeling and functional analyses using a variety of publicly available databases. We used an electronic health record cohort to replicate our top mechanistic finding.Results: One SNP, rs62283056, in the first intron of Mendelian deafness gene WFS1 (wolframin ER transmembrane glycoprotein) and an expression quantitative trait locus (eQTL) for WFS1 met genome-wide significance for association with CAO (P = 1.4 × 10-8). A significant interaction between cumulative cisplatin dose and rs62283056 genotype was evident, indicating that higher cisplatin doses exacerbate hearing loss in patients with the minor allele (P = 0.035). The association between decreased WFS1 expression and hearing loss was replicated in an independent BioVU cohort (n = 18,620 patients, Bonferroni adjusted P < 0.05). Beyond this top signal, we show CAO is a polygenic trait and that SNPs in and near 84 known Mendelian deafness genes are significantly enriched for low P values in the GWAS (P = 0.048).Conclusions: We show for the first time the role of WFS1 in CAO and document a statistically significant interaction between increasing cumulative cisplatin dose and rs62283056 genotype. Our clinical translational results demonstrate that pretherapy patient genotyping to minimize ototoxicity could be useful when deciding between cisplatin-based chemotherapy regimens of comparable efficacy with different cumulative doses.