Variants in WFS1 and Other Mendelian Deafness Genes Are Associated with Cisplatin-Associated Ototoxicity

Strategies to Mitigate Cisplatin-Induced Ototoxicity: A Literature Review of Protective Agents, Mechanisms, and Clinical Gaps

BACKGROUND

Cisplatin, a widely used chemotherapeutic agent, is associated with significant ototoxicity, leading to progressive and irreversible sensorineural hearing loss in up to 93% of patients. Cisplatin generates reactive oxygen species (ROS) in the cochlea, activating apoptotic and necroptotic pathways that result in hair cell death. Inflammatory processes and nitrative stress also contribute to cochlear damage.

METHODS

This literature review was conducted to explore the mechanisms underlying cisplatin-induced ototoxicity and evaluate protective strategies, including both current and emerging approaches. A structured search was performed in multiple scientific databases, including PubMed and ScienceDirect, for articles published up to November 2024.

RESULTS

Current otoprotective strategies include systemic interventions such as antioxidants, anti-inflammatory agents, and apoptosis inhibitors, as well as localized delivery methods like intratympanic injection and nanoparticle-based systems. However, these approaches have limitations, including potential interference with cisplatin's antitumor efficacy and systemic side effects. Emerging strategies focus on genetic and biomarker-based risk stratification, novel otoprotective agents targeting alternative pathways, and combination therapies. Repurposed drugs like pravastatin also show promise in reducing cisplatin-induced ototoxicity.

CONCLUSIONS

Despite these advancements, significant research gaps remain in translating preclinical findings to clinical applications and developing selective otoprotective agents that do not compromise cisplatin's efficacy. This review examines the mechanisms of cisplatin-induced ototoxicity, current otoprotective strategies, and emerging approaches to mitigate this adverse effect.

Machine learning model identifies genetic predictors of cisplatin-induced ototoxicity in CERS6 and TLR4

BACKGROUND

Cisplatin-induced ototoxicity remains a significant concern in pediatric cancer treatment due to its permanent impact on quality of life. Previously, genetic association analyses have been performed to detect genetic variants associated with this adverse reaction.

METHODS

In this study, a combination of interpretable neural networks and Generative Adversarial Networks (GANs) was employed to identify genetic markers associated with cisplatin-induced ototoxicity. The applied method, BRI-Net, incorporates biological domain knowledge to define the network structure and employs adversarial training to learn an unbiased representation of the data, which is robust to known confounders. Leveraging genomic data from a cohort of 362 cisplatin-treated pediatric cancer patients recruited by the CPNDS (Canadian Pharmacogenomics Network for Drug Safety), this model revealed two statistically significant single nucleotide polymorphisms to be associated with cisplatin-induced ototoxicity.

RESULTS

Two markers within the CERS6 (rs13022792, p-value: 3 × 10-4) and TLR4 (rs10759932, p-value: 7 × 10-4) genes were associated with this cisplatin-induced adverse reaction. CERS6, a ceramide synthase, contributes to elevated ceramide levels, a known initiator of apoptotic signals in mouse models of inner ear hair cells. TLR4, a pattern-recognition protein, initiates inflammation in response to cisplatin, and reduced TLR4 expression has been shown in murine hair cells to confer protection from ototoxicity.

CONCLUSION

Overall, these findings provide a foundation for understanding the genetic landscape of cisplatin-induced ototoxicity, with implications for improving patient care and treatment outcomes.

Leveraging large-scale datasets and single cell omics data to develop a polygenic score for cisplatin-induced ototoxicity

BACKGROUND

Cisplatin-induced ototoxicity (CIO), characterized by irreversible and progressive bilateral hearing loss, is a prevalent adverse effect of cisplatin chemotherapy. Alongside clinical risk factors, genetic variants contribute to CIO and genome-wide association studies (GWAS) have highlighted the polygenicity of this adverse drug reaction. Polygenic scores (PGS), which integrate information from multiple genetic variants across the genome, offer a promising tool for the identification of individuals who are at higher risk for CIO. Integrating large-scale hearing loss GWAS data with single cell omics data holds potential to overcome limitations related to small sample sizes associated with CIO studies, enabling the creation of PGSs to predict CIO risk.

RESULTS

We utilized a large-scale hearing loss GWAS and murine inner ear single nuclei RNA-sequencing (snRNA-seq) data to develop two polygenic scores: a hearing loss PGS (PGSHL) and a biologically informed PGS for CIO (PGSCIO). The PGSCIO included only variants which mapped to genes that were differentially expressed within cochlear cells that showed differential abundance in the murine snRNA-seq data post-cisplatin treatment. Evaluation of the association of these PGSs with CIO in our target CIO cohort revealed that PGSCIO demonstrated superior performance (P = 5.54 × 10- 5) relative to PGSHL (P = 2.93 × 10- 3). PGSCIO was also associated with CIO in our test cohort (P = 0.04), while the PGSHL did not show a significant association with CIO (P = 0.52).

CONCLUSION

This study developed the first PGS for CIO using a large-scale hearing loss dataset and a biologically informed filter generated from cisplatin-treated murine inner ear snRNA-seq data. This innovative approach offers new avenues for developing PGSs for pharmacogenomic traits, which could contribute to the implementation of tailored therapeutic interventions. Further, our approach facilitated the identification of specific cochlear cells that may play critical roles in CIO. These novel insights will guide future research aimed at developing targeted therapeutic strategies to prevent CIO.

The role of genetic variants in the prediction of hearing loss due to cisplatin chemoradiotherapy

BACKGROUND

Concomitant high-dose cisplatin with radiotherapy is commonly used for treating head and neck squamous cell carcinoma (HNSCC). Cisplatin, often used with radiotherapy, is known for causing irreversible sensorineural hearing loss, with individual variability suggesting a genetic component. This study aims to enhance the predictive ability of the clinical prediction model for cisplatin-induced hearing loss (CIHL) in HNSCC patients, as outlined in Theunissen et al., by incorporating significant genetic variants.

METHODS

Conducted at the Netherlands Cancer Institute, this retrospective study included 74 patients treated between 1997 and 2011. Thirty-one SNPs that were previously associated with CIHL or other cisplatin-induced toxicities were identified and incorporated into the model. The primary outcome measured was the change in decibels at posttreatment 1-2-4 kHz hearing levels per additional minor allele of these SNPs, evaluated using linear mixed-effects regression models. The model's predictive accuracy was determined by the area under the curve (AUC) using 10-fold cross-validation.

RESULTS

The rs2289669 SNP in the SLC47A1/MATE1 gene was linked to a significant 2.67 dB increase in hearing loss per allele (95% CI 0.49-4.86, p = 0.017). Incorporating rs2289669 improved the model's AUC from 0.78 to 0.83, a borderline significant improvement (p = 0.073).

CONCLUSIONS

This study underscores the importance of the rs2289669 SNP in CIHL and demonstrates the potential of combining genetic and clinical data for enhanced predictive models in personalized treatment strategies.

Loss of Fascin2 increases susceptibility to cisplatin-induced hearing impairment and cochlear cell apoptosis in mice

Objectives

Deletion of Fscn2 gene in mice has been linked to progressive hearing loss and degeneration of cochlear cells. Cisplatin, an antitumor drug, can cause various side effects, including ototoxicity. The aim of this study was to investigate the effects of Fscn2 on cisplatin-induced hearing impairment in mice and to explore the possible mechanism.

Methods

Two-week-old Fscn2 +/+ mice and Fscn2 -/- mice were treated with two doses of cisplatin, with a 3-day recovery period in between. ABR (auditory evoked brain stem response) thresholds were measured and cochlear pathology was observed at 3 weeks of age.

Results

Both Fscn2 +/+ and Fscn2 -/- mice showed hearing loss under the effect of cisplatin, but the impairment was more severe in Fscn2 -/- mice. Further experiments showed that the percentages of outer hair cell (OHC) and spiral ganglion neuron (SGN) loss were significantly higher in cisplatin-treated Fscn2 -/- mice compared to Fscn2 +/+ mice. Additionally, knockdown of Fscn2 in HEI-OC1 cells worsened cisplatin-induced cell apoptosis.

Conclusion

FSCN2 mediates reduction of CDDP induced ototoxicity by inhibiting cell apoptosis.

Drug-induced hearing loss: Listening to the latest advances

Sensorineural hearing loss (SNHL) is the most common type of hearing loss. Causes include degenerative changes in the sensory hair cells, their synapses and/or the cochlear nerve. As human inner ear hair cells have no capacity for regeneration, their destruction is irreversible and leads to permanent hearing loss. SNHL can be genetically inherited or acquired through ageing, exposure to noise or ototoxic drugs. Ototoxicity generally refers to damage to the structures and functions of the inner ear following exposure to specific drugs. Ototoxicity can be multifactorial, causing damage to cochlear hair cells or cells with homeostatic functions that modulate cochlear hair cell function. Clinical strategies to limit ototoxicity include identifying patients at risk, monitoring drug concentrations, performing serial hearing assessments and switching to less ototoxic therapy. This review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, using the PubMed® database. The search terms "ototoxicity", "hearing loss" and "drugs" were combined. We included studies published between September 2013 and June 2023, and focused on medicines and drugs used in hospitals. The review highlighted a number of articles reporting the main drug classes potentially involved: namely, immunosuppressants, antimalarials, vaccines, antibiotics, antineoplastic agents, diuretics, nonsteroidal anti-inflammatory drugs and analgesics. The presumed ototoxic mechanisms were described, together with the therapeutic and preventive options developed over the last ten years.

Prediction of Tumor Microenvironment Characteristics and Treatment Response in Lung Squamous Cell Carcinoma by Pseudogene OR7E47P-related Immune Genes

OBJECTIVE

Pseudogenes are initially regarded as nonfunctional genomic sequences, but some pseudogenes regulate tumor initiation and progression by interacting with other genes to modulate their transcriptional activities. Olfactory receptor family 7 subfamily E member 47 pseudogene (OR7E47P) is expressed broadly in lung tissues and has been identified as a positive regulator in the tumor microenvironment (TME) of lung adenocarcinoma (LUAD). This study aimed to elucidate the correlation between OR7E47P and tumor immunity in lung squamous cell carcinoma (LUSC).

METHODS

Clinical and molecular information from The Cancer Genome Atlas (TCGA) LUSC cohort was used to identify OR7E47P-related immune genes (ORIGs) by weighted gene correlation network analysis (WGCNA). Based on the ORIGs, 2 OR7E47P clusters were identified using non-negative matrix factorization (NMF) clustering, and the stability of the clustering was tested by an extreme gradient boosting classifier (XGBoost). LASSO-Cox and stepwise regressions were applied to further select prognostic ORIGs and to construct a predictive model (ORPScore) for immunotherapy. The Botling cohorts and 8 immunotherapy cohorts (the Samstein, Braun, Jung, Gide, IMvigor210, Lauss, Van Allen, and Cho cohorts) were included as independent validation cohorts.

RESULTS

OR7E47P expression was positively correlated with immune cell infiltration and enrichment of immune-related pathways in LUSC. A total of 57 ORIGs were identified to classify the patients into 2 OR7E47P clusters (Cluster 1 and Cluster 2) with distinct immune, mutation, and stromal programs. Compared to Cluster 1, Cluster 2 had more infiltration by immune and stromal cells, lower mutation rates of driver genes, and higher expression of immune-related proteins. The clustering performed well in the internal and 5 external validation cohorts. Based on the 7 ORIGs (HOPX, STX2, WFS, DUSP22, SLFN13, GGCT, and CCSER2), the ORPScore was constructed to predict the prognosis and the treatment response. In addition, the ORPScore was a better prognostic factor and correlated positively with the immunotherapeutic response in cancer patients. The area under the curve values ranged from 0.584 to 0.805 in the 6 independent immunotherapy cohorts.

CONCLUSION

Our study suggests a significant correlation between OR7E47P and TME modulation in LUSC. ORIGs can be applied to molecularly stratify patients, and the ORPScore may serve as a biomarker for clinical decision-making regarding individualized prognostication and immunotherapy.

Systematic Critical Review of Genetic Factors Associated with Cisplatin-induced Ototoxicity: Canadian Pharmacogenomics Network for Drug Safety 2022 Update

BACKGROUND

Cisplatin is commonly used to treat solid tumors; however, its use can be complicated by drug-induced hearing loss (ie, ototoxicity). The presence of certain genetic variants has been associated with the development/occurrence of cisplatin-induced ototoxicity, suggesting that genetic factors may be able to predict patients who are more likely to develop ototoxicity. The authors aimed to review genetic associations with cisplatin-induced ototoxicity and discuss their clinical relevance.

METHODS

An updated systematic review was conducted on behalf of the Canadian Pharmacogenomics Network for Drug Safety, based on the Preferred Reporting Items for Systematic reviews and Meta-Analyses 2020 statement. Pharmacogenomic studies that reported associations between genetic variation and cisplatin-induced ototoxicity were included. The evidence on genetic associations was summarized and evaluated, and knowledge gaps that can be used to inform future pharmacogenomic studies identified.

RESULTS

Overall, 40 evaluated reports, considering 47 independent patient populations, captured associations involving 24 genes. Considering GRADE criteria, genetic variants in 2 genes were strongly (ie, odds ratios ≥3) and consistently (ie, replication in ≥3 independent populations) predictive of cisplatin-induced ototoxicity. Specifically, an ACYP2 variant has been associated with ototoxicity in both children and adults, whereas TPMT variants are relevant in children. Encouraging evidence for associations involving several other genes also exists; however, further research is necessary to determine potential clinical relevance.

CONCLUSIONS

Genetic variation in ACYP2 and TPMT may be helpful in predicting patients at the highest risk of developing cisplatin-induced ototoxicity. Further research (including replication studies considering diverse pediatric and adult patient populations) is required to determine whether genetic variation in additional genes may help further identify patients most at risk.

Predicting Hearing Loss in Testicular Cancer Patients after Cisplatin-Based Chemotherapy

Testicular cancer is predominantly curable, but the long-term side effects of chemotherapy have a severe impact on life quality. In this research study, we focus on hearing loss as a part of overall chemotherapy-induced ototoxicity. This is a unique approach where we combine clinical data from the acclaimed nationwide Danish Testicular Cancer (DaTeCa)-Late database. Clinical and genetic data on 433 patients were collected from hospital files in October 2014. Hearing loss was classified according to the FACT/GOG-Ntx-11 version 4 self-reported Ntx6. Machine learning models combining a genome-wide association study within a nested cross-validated logistic regression were applied to identify patients at high risk of hearing loss. The model comprising clinical and genetic data identified 67% of the patients with hearing loss; however, this was with a false discovery rate of 49%. For the non-affected patients, the model identified 66% of the patients with a false omission rate of 19%. An area under the receiver operating characteristic (ROC-AUC) curve of 0.73 (95% CI, 0.71-0.74) was obtained, and the model suggests genes SOD2 and MGST3 as important in improving prediction over the clinical-only model with a ROC-AUC of 0.66 (95% CI, 0.65-0.66). Such prediction models may be used to allow earlier detection and prevention of hearing loss. We suggest a possible biological mechanism for cisplatin-induced hearing loss development. On confirmation in larger studies, such models can help balance treatment in clinical practice.

Clinical and genome-wide association analysis of chemoradiation-induced hearing loss in nasopharyngeal carcinoma

Chemoradiation-induced hearing loss (CRIHL) is one of the most devasting side effects for nasopharyngeal carcinoma (NPC) patients, which seriously affects survivors' long-term quality of life. However, few studies have comprehensively characterized the risk factors for CRIHL. In this study, we found that age at diagnosis, tumor stage, and concurrent cisplatin dose were positively associated with chemoradiation-induced hearing loss. We performed a genome-wide association study (GWAS) in 777 NPC patients and identified rs1050851 (within the exon 2 of NFKBIA), a variant with a high deleteriousness score, to be significantly associated with hearing loss risk (HR = 5.46, 95% CI 2.93-10.18, P = 9.51 × 10^-08). The risk genotype of rs1050851 was associated with higher NFKBIA expression, which was correlated with lower cellular tolerance to cisplatin. According to permutation-based enrichment analysis, the variants mapping to 149 hereditary deafness genes were significantly enriched among GWAS top signals, which indicated the genetic similarity between hereditary deafness and CRIHL. Pathway analysis suggested that synaptic signaling was involved in the development of CRIHL. Additionally, the risk score integrating genetic and clinical factors can predict the risk of hearing loss with a relatively good performance in the test set. Collectively, this study shed new light on the etiology of chemoradiation-induced hearing loss, which facilitates high-risk individuals' identification for personalized prevention and treatment.

Association of Clinical Aspects and Genetic Variants with the Severity of Cisplatin-Induced Ototoxicity in Head and Neck Squamous Cell Carcinoma: A Prospective Cohort Study

Background: Cisplatin (CDDP) is a major ototoxic chemotherapy agent for head and neck squamous cell carcinoma (HNSCC) treatment. Clinicopathological features and genotypes encode different stages of CDDP metabolism, as their coexistence may influence the prevalence and severity of hearing loss. Methods: HNSCC patients under CDDP chemoradiation were prospectively provided with baseline and post-treatment audiometry. Clinicopathological features and genetic variants encoding glutathione S-transferases (GSTT1, GSTM1, GSTP1), nucleotide excision repair (XPC, XPD, XPF, ERCC1), mismatch repair (MLH1, MSH2, MSH3, EXO1), and apoptosis (P53, CASP8, CASP9, CASP3, FAS, FASL)-related proteins were analyzed regarding ototoxicity. Results: Eighty-nine patients were included, with a cumulative CDDP dose of 260 mg/m2. Moderate/severe ototoxicity occurred in 26 (29%) patients, particularly related to hearing loss at frequencies over 3000 Hertz. Race, body-mass index, and cumulative CDDP were independent risk factors. Patients with specific isolated and combined genotypes of GSTM1, GSTP1 c.313A>G, XPC c.2815A>C, XPD c.934G>A, EXO1 c.1762G>A, MSH3 c.3133A>G, FASL c.-844A>T, and P53 c.215G>C SNVs had up to 32.22 higher odds of presenting moderate/severe ototoxicity. Conclusions: Our data present, for the first time, the association of combined inherited nucleotide variants involved in CDDP efflux, DNA repair, and apoptosis with ototoxicity, which could be potential predictors in future clinical and genomic models.

Systematic Review and Meta-Analysis of the Influence of Genetic Variation on Ototoxicity in Platinum-Based Chemotherapy

OBJECTIVE

The objective of this meta-analysis is to evaluate the impact of genetic polymorphisms on platinum-based chemotherapy (PBC)-induced ototoxicity.

DATA SOURCES

Systematic searches of PubMed, Embase, Cochrane, and Web of Science were conducted from the inception of the databases to May 31, 2022. Abstracts and presentations from conferences were also reviewed.

REVIEW METHODS

Four investigators independently extracted data in adherence to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Differences in the prevalence of PBC-induced ototoxicity between reference and variant (i) genotypes and (ii) alleles were analyzed. The overall effect size was presented using the random-effects model as an odds ratio (OR) with a 95% confidence interval (CI).

RESULTS

From 32 included articles, 59 single nucleotide polymorphisms on 28 genes were identified, with 4406 total unique participants. For allele frequency analysis, the A allele in ACYP2 rs1872328 was positively associated with ototoxicity (OR: 2.61; 95% CI: 1.06-6.43; n = 2518). Upon limiting to cisplatin use only, the T allele of COMT rs4646316 and COMT rs9332377 revealed significant results. For genotype frequency analysis, the CT/TT genotype in ERCC2 rs1799793 demonstrated an otoprotective effect (OR: 0.50; 95% CI: 0.27-0.94; n = 176). Excluding studies using carboplatin or concomitant radiotherapy revealed significant effects with COMT rs4646316, GSTP1 rs1965, and XPC rs2228001. Major sources of variations between studies include differences in patient demographics, ototoxicity grading systems, and treatment protocols.

CONCLUSION

Our meta-analysis presents polymorphisms that exert ototoxic or otoprotective effects in patients undergoing PBC. Importantly, several of these alleles are observed at high frequencies globally, highlighting the potential for polygenic screening and cumulative risk evaluation for personalized care.

Prevalence and risk factors for ototoxicity after cisplatin-based chemotherapy

PURPOSE

Ototoxicity is a prominent side effect of cisplatin-based chemotherapy. There are few reports, however, estimating its prevalence in well-defined cohorts and associated risk factors.

METHODS

Testicular cancer (TC) survivors given first-line cisplatin-based chemotherapy completed validated questionnaires. Descriptive statistics evaluated the prevalence of ototoxicity, defined as self-reported hearing loss and/or tinnitus. We compared patients with and without tinnitus or hearing loss using Chi-square test, two-sided Fisher's exact test, or two-sided Wilcoxon rank sum test. To evaluate ototoxicity risk factors, a backward selection logistic regression procedure was performed.

RESULTS

Of 145 TC survivors, 74% reported ototoxicity: 68% tinnitus; 59% hearing loss; and 52% reported both. TC survivors with tinnitus were more likely to indicate hypercholesterolemia (P = 0.008), and difficulty hearing (P < .001). Tinnitus was also significantly related to age at survey completion (OR = 1.79; P = 0.003) and cumulative cisplatin dose (OR = 5.17; P < 0.001). TC survivors with hearing loss were more likely to report diabetes (P = 0.042), hypertension (P = 0.007), hypercholesterolemia (P < 0.001), and family history of hearing loss (P = 0.044). Risk factors for hearing loss included age at survey completion (OR = 1.57; P = 0.036), hypercholesterolemia (OR = 3.45; P = 0.007), cumulative cisplatin dose (OR = 1.94; P = 0.049), and family history of hearing loss (OR = 2.87; P = 0.071).

CONCLUSIONS

Ototoxicity risk factors included age, cisplatin dose, cardiovascular risk factors, and family history of hearing loss. Three of four TC survivors report some type of ototoxicity; thus, follow-up of cisplatin-treated survivors should include routine assessment for ototoxicity with provision of indicated treatments.

IMPLICATIONS FOR CANCER SURVIVORS

Survivors should be aware of risk factors associated with ototoxicity. Referrals to audiologists before, during, and after cisplatin treatment is recommended.

Comprehensive association analysis of speech recognition thresholds after cisplatin-based chemotherapy in survivors of adult-onset cancer

PURPOSE

Deficits in speech understanding constitute one of the most severe consequences of hearing loss. Here we investigate the clinical and genetic risk factors for symmetric deterioration of speech recognition thresholds (SRT) among cancer survivors treated with cisplatin.

METHODS

SRT was measured using spondaic words and calculating the mean of measurements for both ears with symmetric SRT values. For clinical associations, SRT-based hearing disability (SHD) was defined as SRT≥15 dB hearing loss and clinical variables were derived from the study dataset. Genotyped blood samples were used for GWAS with rank-based inverse normal transformed SRT values as the response variable. Age was used as a covariate in association analyses.

RESULTS

SHD was inversely associated with self-reported health (p = 0.004). Current smoking (p = 0.002), years of smoking (p = 0.02), BMI (p < 0.001), and peripheral motor neuropathy (p = 0.003) were positively associated with SHD, while physical activity was inversely associated with SHD (p = 0.005). In contrast, cumulative cisplatin dose, peripheral sensory neuropathy, hypertension, and hypercholesterolemia were not associated with SHD. Although no genetic variants had an association p value < 5 × 10-8 , 22 genetic variants were suggestively associated (p < 10-5 ) with SRT deterioration. Three of the top variants in 10 respective linkage disequilibrium regions were either positioned within the coding sequence or were eQTLs for genes involved in neuronal development (ATE1, ENAH, and ZFHX3).

CONCLUSION

Current results improve our understanding of risk factors for SRT deterioration in cancer survivors. Higher BMI, lower physical activity, and smoking are associated with SHD. Larger samples would allow for expansion of the current findings on the genetic architecture of SRT.

Ototoxicity prognostic models in adult and pediatric cancer patients: a rapid review

PURPOSE

A cornerstone of treatment for many cancers is the administration of platinum-based chemotherapies and/or ionizing radiation, which can be ototoxic. An accurate ototoxicity risk assessment would be useful for counseling, treatment planning, and survivorship follow-up in patients with cancer.

METHODS

This systematic review evaluated the literature on predictive models for estimating a patient's risk for chemotherapy-related auditory injury to accelerate development of computational approaches for the clinical management of ototoxicity in cancer patients. Of the 1195 articles identified in a PubMed search from 2010 forward, 15 studies met inclusion for the review.

CONCLUSIONS

All but 1 study used an abstraction of the audiogram as a modeled outcome; however, specific outcome measures varied. Consistently used predictors were age, baseline hearing, cumulative cisplatin dose, and radiation dose to the cochlea. Just 5 studies were judged to have an overall low risk of bias. Future studies should attempt to minimize bias by following statistical best practices including not selecting multivariate predictors based on univariate analysis, validation in independent cohorts, and clearly reporting the management of missing and censored data. Future modeling efforts should adopt a transdisciplinary approach to define a unified set of clinical, treatment, and/or genetic risk factors. Creating a flexible model that uses a common set of predictors to forecast the full post-treatment audiogram may accelerate work in this area. Such a model could be adapted for use in counseling, treatment planning, and follow-up by audiologists and oncologists and could be incorporated into ototoxicity genetic association studies as well as clinical trials investigating otoprotective agents.

IMPLICATIONS FOR CANCER SURVIVORS

Improvements in the ability to model post-treatment hearing loss can help to improve patient quality of life following cancer care. The improvements advocated for in this review should allow for the acceleration of advancements in modeling the auditory impact of these treatments to support treatment planning and patient counseling during and after care.

Genome-wide analyses of platinum-induced ototoxicity in childhood cancer patients: Results of GO-CAT and United Kingdom MAGIC consortia

Hearing loss (ototoxicity) is a major adverse effect of cisplatin and carboplatin chemotherapy. The aim of this study is to identify novel genetic variants that play a role in platinum-induced ototoxicity. Therefore, a genome-wide association study was performed in the Genetics of Childhood Cancer Treatment (GO-CAT) cohort (n = 261) and the United Kingdom Molecular Genetics of Adverse Drug Reactions in Children Study (United Kingdom MAGIC) cohort (n = 248). Results of both cohorts were combined in a meta-analysis. In primary analysis, patients with SIOP Boston Ototoxicity Scale grade ≥1 were considered cases, and patients with grade 0 were controls. Variants with a p-value <10^-5 were replicated in previously published data by the PanCareLIFE cohort (n = 390). No genome-wide significant associations were found, but variants in TSPAN5, RBBP4P5, AC010090.1 and RNU6-38P were suggestively associated with platinum-induced ototoxicity. The lowest p-value was found for rs7671702 in TSPAN5 (odds ratio 2.0 (95% confidence interval 1.5-2.7), p-value 5.0 × 10^-7). None of the associations were significant in the replication cohort, although the effect directions were consistent among all cohorts. Validation and functional understanding of these genetic variants could lead to more insights in the development of platinum-induced ototoxicity.

Modern developments in germline pharmacogenomics for oncology prescribing

The integration of genomic data into personalized treatment planning has revolutionized oncology care. Despite this, patients with cancer remain vulnerable to high rates of adverse drug events and medication inefficacy, affecting prognosis and quality of life. Pharmacogenomics is a field seeking to identify germline genetic variants that contribute to an individual's unique drug response. Although there is widespread integration of genomic information in oncology, somatic platforms, rather than germline biomarkers, have dominated the attention of cancer providers. Patients with cancer potentially stand to benefit from improved integration of both somatic and germline genomic information, especially because the latter may complement treatment planning by informing toxicity risk for drugs with treatment-limiting tolerabilities and narrow therapeutic indices. Although certain germline pharmacogenes, such as TPMT, UGT1A1, and DPYD, have been recognized for decades, recent attention has illuminated modern potential dosing implications for a whole new set of anticancer agents, including targeted therapies and antibody-drug conjugates, as well as the discovery of additional genetic variants and newly relevant pharmacogenes. Some of this information has risen to the level of directing clinical action, with US Food and Drug Administration label guidance and recommendations by international societies and governing bodies. This review is focused on key new pharmacogenomic evidence and oncology-specific dosing recommendations. Personalized oncology care through integrated pharmacogenomics represents a unique multidisciplinary collaboration between oncologists, laboratory science, bioinformatics, pharmacists, clinical pharmacologists, and genetic counselors, among others. The authors posit that expanded consideration of germline genetic information can further transform the safe and effective practice of oncology in 2022 and beyond.

Family Socioeconomic Position and Lung Cancer Risk: A Meta-Analysis and a Mendelian Randomization Study

Background

Family socioeconomic position (SEP) in childhood is an important factor to predict some chronic diseases. However, the association between family SEP in childhood and the risk of lung cancer is not clear.

Methods

A systematic search was performed to explore their relationship. We selected education level, socioeconomic positions of parents and childhood housing conditions to represent an individual family SEP. Hazard ratios (HRs) of lung cancer specific-mortality were synthesized using a random effects model. Two-sample Mendelian randomization (MR) was carried out with summary data from published genome-wide association studies of SEP to assess the possible causal relationship of SEP and risk of lung cancer.

Results

Through meta-analysis of 13 studies, we observed that to compared with the better SEP, the poorer SEP in the childhood was associated with the increased lung cancer risk in the adulthood (HR: 1.25, 95% CI: 1.10 to 1.43). In addition, the dose-response analysis revealed a positive correlation between the poorer SEP and increased lung cancer risk. Same conclusion was reached in MR [(education level) OR 0.50, 95% CI: 0.39 to 0.63; P &lt; 0.001].

Conclusion

This study indicates that poor family socioeconomic position in childhood is causally correlated with lung cancer risk in adulthood.

Systematic Review Registration

identifier: 159082.

Associations of Body Fat Distribution and Cardiometabolic Risk of Testicular Cancer Survivors after Cisplatin-Based Chemotherapy

Background

It is unknown how body fat distribution modulates the cardiometabolic risk of testicular cancer survivors (TCSs) after cisplatin-based chemotherapy.

Methods

For 455 patients enrolled in The Platinum Study at Memorial Sloan Kettering Cancer Center, visceral (VAT) and subcutaneous (SAT) adipose tissue was quantified on pre-chemotherapy CT. VAT/SAT ratio was calculated as a quantitative measure of central adiposity. Endpoints were incidence of new post-chemotherapy cardiometabolic disease (new antihypertensive, lipid-lowering, or diabetes medication), and post-chemotherapy Framingham risk scores. Cox models and linear regression with interaction terms were applied. Post-chemotherapy body fat distribution was analyzed in 108 patients. All statistical tests were 2-sided.

Results

Baseline median age was 31 years (IQR = 26, 39), BMI 26 kg/m2 (IQR: 24, 29), and VAT/SAT ratio 0.49 (IQR: 0.31, 0.75). Median follow-up was 26 months (IQR: 16, 59). Higher pre-chemotherapy VAT/SAT ratios inferred a higher likelihood of new cardiometabolic disease among patients with BMI ≥30 kg/m2 (age-adjusted HR = 3.14, 95% CI = 1.02–9.71, p = 0.047), but not other BMI groups. Pre-chemotherapy VAT/SAT ratio was associated with post-chemotherapy Framingham risk scores in univariate regression analysis (exp(β)-estimate: 2.10, 95% CI: 1.84, 2.39, p &lt; 0.001); in a multivariate model, this association was stronger in younger versus older individuals. BMI increased in most patients after chemotherapy and correlated with increases in VAT/SAT (Spearman r = 0.39; p &lt; 0.001).

Conclusions

In TCSs, central adiposity is associated with increased cardiometabolic risk after cisplatin-based chemotherapy, particularly in obese or young men. Weight gain after chemotherapy occurs preferentially in the visceral compartment, providing insight into the pathogenesis of cardiovascular disease in this population.

Pharmacogenomics of cisplatin-induced neurotoxicities: Hearing loss, tinnitus, and peripheral sensory neuropathy

PURPOSE

Cisplatin is a critical component of first-line chemotherapy for several cancers, but causes peripheral sensory neuropathy, hearing loss, and tinnitus. We aimed to identify comorbidities for cisplatin-induced neurotoxicities among large numbers of similarly treated patients without the confounding effect of cranial radiotherapy.

METHODS

Utilizing linear and logistic regression analyses on 1680 well-characterized cisplatin-treated testicular cancer survivors, we analyzed associations of hearing loss, tinnitus, and peripheral neuropathy with nongenetic comorbidities. Genome-wide association studies and gene-based analyses were performed on each phenotype.

RESULTS

Hearing loss, tinnitus, and peripheral neuropathy, accounting for age and cisplatin dose, were interdependent. Survivors with these neurotoxicities experienced more hypertension and poorer self-reported health. In addition, hearing loss was positively associated with BMIs at clinical evaluation and nonwork-related noise exposure (>5 h/week). Tinnitus was positively associated with tobacco use, hypercholesterolemia, and noise exposure. We observed positive associations between peripheral neuropathy and persistent vertigo, tobacco use, and excess alcohol consumption. Hearing loss and TXNRD1, which plays a key role in redox regulation, showed borderline significance (p = 4.2 × 10^-6 ) in gene-based analysis. rs62283056 in WFS1 previously found to be significantly associated with hearing loss (n = 511), was marginally significant in an independent replication cohort (p = 0.06; n = 606). Gene-based analyses identified significant associations between tinnitus and WNT8A (p = 2.5 × 10^-6 ), encoding a signaling protein important in germ cell tumors.

CONCLUSIONS

Genetics variants in TXNRD1 and WNT8A are notable risk factors for hearing loss and tinnitus, respectively. Future studies should investigate these genes and if replicated, identify their potential impact on preventive strategies.

Genome-wide analysis identify novel germline genetic variations in ADCY1 influencing platinum-based chemotherapy response in non-small cell lung cancer

To explore the pharmacogenomic markers that affect the platinum-based chemotherapy response in non-small-cell lung carcinoma (NSCLC), we performed a two-cohort of genome-wide association studies (GWAS), including 34 for WES-based and 433 for microarray-based analyses, as well as two independent validation cohorts. After integrating the results of two studies, the genetic variations related to the platinum-based chemotherapy response were further determined by fine-mapping in 838 samples, and their potential functional impact were investigated by eQTL analysis and in vitro cell experiments. We found that a total of 68 variations were significant at P < 1 × 10^-3 in cohort 1 discovery stage, of which 3 SNPs were verified in 262 independent samples. A total of 541 SNPs were significant at P < 1 × 10^-4 in cohort 2 discovery stage, of which 8 SNPs were verified in 347 independent samples. Comparing the validated SNPs in two GWAS, ADCY1 gene was verified in both independent studies. The results of fine-mapping showed that the G allele carriers of ADCY1 rs2280496 and C allele carriers of rs189178649 were more likely to be resistant to platinum-based chemotherapy. In conclusion, our study found that rs2280496 and rs189178649 in ADCY1 gene were associated the sensitivity of platinum-based chemotherapy in NSCLC patients.

Incidence of childhood hearing loss after in utero exposure to platinum agents

OBJECTIVE

When treated for childhood cancers, at least 50% of children exposed to platinum agents have permanent hearing loss. We determined the relative risk of childhood hearing loss after in utero exposure to platinum chemotherapy in our registry cohort.

METHOD

After exposure to platinum chemotherapy in utero, all children undergo routine newborn hearing screening. This consists of Otoacoustic Emissions. Children who failed this screen were evaluated by audiologists. For those children with hearing loss by Automated Auditory Brainstem Response, prenatal and postnatal treatment details were compared to platinum exposed children without hearing loss.

RESULTS

Three hundred and seven children were exposed to chemotherapy in utero. Four children were diagnosed with hearing loss, all exposed to platinum agents. Chemotherapy exposures included: Cisplatin/Paclitaxel (2), Etoposide/Cisplatin/Bleomycin (1), Carboplatin/Paclitaxel (1) to treat ovarian (2), or cervical cancer (2). Of the 39 platinum exposed without hearing loss: 11 children were exposed to oxaliplatin, 16 were exposed to cisplatin and 12 to carboplatin in utero. Two hundred and sixty four women received non-platinum based chemotherapy for various cancers during pregnancy. Among these, there were no cases of hearing loss. There was a significant difference in hearing loss based on exposure to platinum agents in utero compared to non-platinum-containing chemotherapy regimens, 4/43 versus 0/264, p = 0.0003. There were no statistical differences in prenatal and postnatal treatment details, including: gestational age at diagnosis, at first chemotherapy treatment, at first platinum treatment, at delivery (<32 weeks, <35 weeks, <37 weeks), gender, birthweight, birthweight percentile, rates of intrauterine growth restriction, neonatal complications or use of postnatal antibiotics between the platinum exposed children with and without hearing loss.

CONCLUSION

The only children in the registry exposed to chemotherapy who were diagnosed with hearing loss had been exposed to cisplatin or carboplatin in utero. No hearing loss occurred in children exposed to oxaliplatin, or non-platinum agents. Due to a concern for cisplatin ototoxicity, carboplatin is the preferred platinum agent for use in pregnancy when equivalent maternal survival can be expected for the particular cancer type. For newborns exposed to platinum agents in utero, newborn screening with an auditory emissions test at birth (OES) may not detect sensorineural hearing loss and auditory brainstem response testing is recommended, regardless of the newborn screening result.

Recommendations for Age-Appropriate Testing, Timing, and Frequency of Audiologic Monitoring During Childhood Cancer Treatment: An International Society of Paediatric Oncology Supportive Care Consensus Report

Importance

Ototoxicity is an irreversible direct and late effect of certain childhood cancer treatments. Audiologic surveillance during therapy as part of the supportive care pathway enables early detection of hearing loss, decision-making about ongoing cancer treatment, and, when applicable, the timely use of audiologic interventions. Pediatric oncologic clinical practice and treatment trials have tended to be driven by tumor type and tumor-specific working groups. Internationally accepted standardized recommendations for monitoring hearing during treatment have not previously been agreed on.

Objective

To provide standard recommendations on hearing loss monitoring during childhood cancer therapy for clinical practice.

Methods

An Ototoxicity Task Force was formed under the umbrella of the International Society of Paediatric Oncology, consisting of international audiologists, otolaryngologists, and leaders in the field of relevant pediatric oncology tumor groups. Consensus meetings conducted by experts were organized, aimed at providing standardized recommendations on age-directed testing, timing, and frequency of monitoring during cancer treatment based on literature and consensus. Consensus statements were prepared by the core group, adapted following several videoconferences, and finally agreed on by the expert panel.

Findings

The consensus reached was that children who receive ototoxic cancer treatment (platinum agents, cranial irradiation, and/or brain surgery) require a baseline case history, monitoring of their middle ear and inner ear function, and assessment of tinnitus at each audiologic follow-up. As a minimum, age-appropriate testing should be performed before and at the end of treatment. Ideally, audiometry with counseling before each cisplatin cycle should be considered in the context of the individual patient, specific disease, feasibility, and available resources.

Conclusions and Relevance

This is an international multidisciplinary consensus report providing standardized supportive care recommendations on hearing monitoring in children undergoing potentially ototoxic cancer treatment. The recommendations are intended to improve the care of children with cancer and facilitate comparative research on the timing and development of hearing loss caused by different cancer treatment regimens.

Testicular cancer: Biology to bedside

Testicular cancer is the first solid tumor with a remarkably high cure rate. This success was only made possible through collaborative efforts of basic and clinical research. Most patients with distant metastases can be cured. However, the majority of these patients are diagnosed at a young age, leaving many decades for the development of treatment-related complications. This has magnified the importance of research into survivorship issues after exposure to platinum-based chemotherapy. This research, along with research into newer biomarkers that will aid in the diagnosis and surveillance of patients and survivors of testicular cancer, will continue to advance the field and provide new opportunities for these patients. There also remains the need for further therapeutic options for patients who unfortunately do not respond to standard treatment regimens and ultimately die from this disease, including a cohort of patients with late relapses and platinum-refractory disease. Here we discuss the advancements in management that led to a highly curable malignancy, while highlighting difficult situations still left to solve as well as emerging research into novel biomarkers.

Clinical and genetic risk factors for radiation-associated ototoxicity: A report from the Childhood Cancer Survivor Study and the St. Jude Lifetime Cohort

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.

Late adverse effects and quality of life in survivors of testicular germ cell tumour

Currently, ~95% of patients with testicular germ cell tumour (TGCT) are cured, resulting in an increasing number of TGCT survivors. Although cured, these men face potential late adverse effects and reduced quality of life. Survivors face a twofold increased risk of second malignant neoplasms after chemotherapy and radiotherapy, with evidence of dose-dependent associations. For survivors managed with surveillance or treated with radiotherapy, the risk of cardiovascular disease (CVD) is comparable to the risk in the general population, whereas treatment with chemotherapy increases the risk of life-threatening CVD, especially during treatment and after 10 years of follow-up. Other adverse effects are organ-related toxicities such as neuropathy and ototoxicity. Pulmonary and renal impairment in patients with TGCT treated with chemotherapy is limited. Survivors of TGCT might experience psychosocial distress including anxiety disorders, fear of cancer recurrence and TGCT-specific issues, such as sexual dysfunction. Late adverse effects can be avoided in most patients with stage I disease if followed on a surveillance programme. However, patients with disseminated disease can experience toxicities associated with radiotherapy and chemotherapy, and/or adverse effects related to surgery for residual disease. The severity of adverse effects increases with dose of both chemotherapy and radiotherapy. This Review discusses the most recent data concerning the late adverse effects of today's standard treatments for TGCT.

Integrating disease and drug-related phenotypes for improved identification of pharmacogenomic variants

Aim: To improve the identification and interpretation of pharmacogenetic variants through the integration of disease and drug-related traits. Materials & methods: We hypothesized that integrating genome-wide disease and pharmacogenomic data may drive new insights into drug toxicity and response by identifying shared genetic architecture. Pleiotropic variants were identified using a methodological framework incorporating colocalization analysis. Results: Using genome-wide association studies summary statistics from the UK Biobank, European Bioinformatics Institute genome-wide association studies catalog and the Pharmacogenomics Research Network, we validated pleiotropy at the ABCG2 locus between allopurinol response and gout and identified novel pleiotropy between antihypertensive-induced new-onset diabetes, Crohn's disease and inflammatory bowel disease at the IL18RAP/SLC9A4 locus. Conclusion: New mechanistic insights and genetic loci can be uncovered by identifying pleiotropy between disease and drug-related traits.

Causal relationship between the timing of menarche and young adult body mass index with consideration to a trend of consistently decreasing age at menarche

Younger age at menarche (AAM) is associated with higher body mass index (BMI) for young women. Considering that continuous trends in decreasing AAM and increasing BMI are found in many countries, we attempted to assess whether the observed negative association between AAM and young adult BMI is causal. We included 4,093 women from the Korean Genome and Epidemiology Study (KoGES) and Healthy twin Study (HTS) with relevant epidemiologic data and genome-wide marker information. To mitigate the remarkable differences in AAM across generations, we converted the AAM to a generation-standardized AAM (gsAAM). To test causality, we applied the Mendelian randomization (MR) approach, using a genetic risk score (GRS) based on 14 AAM-associated single nucleotide polymorphisms (SNPs). We constructed MR models adjusting for education level and validated the results using the inverse-variance weighted (IVW), weighted median (WM), MR-pleiotropy residual sum and outliers test (MR-PRESSO), and MR-Egger regression methods. We found a null association using observed AAM and BMI level (conventional regression; -0.05 [95% CIs -0.10-0.00] per 1-year higher AAM). This null association was replicated when gsAAM was applied instead of AAM. Using the two-stage least squares (2SLS) approach employing a univariate GRS, the association was also negated for both AAM and gsAAM, regardless of model specifications. All the MR diagnostics suggested statistically insignificant associations, but weakly negative trends, without evidence of confounding from pleiotropy. We did not observe a causal association between AAM and young adult BMI whether we considered the birth cohort effect or not. Our study alone does not exclude the possibility of existing a weak negative association, considering the modest power of our study design.

Genome-wide association study of cardiovascular disease in testicular cancer patients treated with platinum-based chemotherapy

Genetic variation may mediate the increased risk of cardiovascular disease (CVD) in chemotherapy-treated testicular cancer (TC) patients compared to the general population. Involved single nucleotide polymorphisms (SNPs) might differ from known CVD-associated SNPs in the general population. We performed an explorative genome-wide association study (GWAS) in TC patients. TC patients treated with platinum-based chemotherapy between 1977 and 2011, age ≤55 years at diagnosis, and ≥3 years relapse-free follow-up were genotyped. Association between SNPs and CVD occurrence during treatment or follow-up was analyzed. Data-driven Expression Prioritized Integration for Complex Trait (DEPICT) provided insight into enriched gene sets, i.e., biological themes. During a median follow-up of 11 years (range 3–37), CVD occurred in 53 (14%) of 375 genotyped patients. Based on 179 SNPs associated at p ≤ 0.001, 141 independent genomic loci associated with CVD occurrence. Subsequent, DEPICT found ten biological themes, with the RAC2/RAC3 network (linked to endothelial activation) as the most prominent theme. Biology of this network was illustrated in a TC cohort (n = 60) by increased circulating endothelial cells during chemotherapy. In conclusion, the ten observed biological themes highlight possible pathways involved in CVD in chemotherapy-treated TC patients. Insight in the genetic susceptibility to CVD in TC patients can aid future intervention strategies.

Clinical and Genome-Wide Analysis of Multiple Severe Cisplatin-Induced Neurotoxicities in Adult-Onset Cancer Survivors

PURPOSE

Cisplatin is a first-line chemotherapeutic for many cancers, but causes neurotoxicity including hearing loss, tinnitus, and peripheral sensory neuropathy. However, no study has comprehensively characterized risk factors for developing multiple (>1) severe neurotoxicities.

EXPERIMENTAL DESIGN

The relationship between multiple severe neurotoxicities and age, cumulative cisplatin dose, medical history, and lifestyle/behavioral factors was evaluated in 300 cisplatin-treated testicular cancer survivors using logistic regression. Case-control genome-wide association study (GWAS; cases, n = 104 and controls, n = 196) was also performed.

RESULTS

Age at clinical examination (P = 6.4 × 10^-16) and cumulative cisplatin dose (P = 5.4 × 10^-4) were positively associated with multiple severe neurotoxicity risk, as were high serum platinum levels (P = 0.02), tobacco use (ever smoker, P = 0.001 and current smoker, P = 0.002), and hypertension (P = 0.01) after adjustment for age and cumulative cisplatin dose. Individuals with multiple severe neurotoxicities were more likely to experience dizziness/vertigo (P = 0.01), Raynaud phenomenon (P = 3.7 × 10^-9), and symptoms consistent with peripheral motor neuropathy (P = 4.3 × 10^-14) after age and dose adjustment. These patients also reported poorer overall health (P = 2.7 × 10^-5) and a greater use of psychotropic medications (P = 0.06). GWAS identified no genome-wide significant SNPs. Gene-based association analysis identified RGS17 (P = 3.9 × 10^-5) and FAM20C (P = 5.5 × 10^-5) as near genome-wide significant. Decreased FAM20C expression was associated with increased cisplatin sensitivity in tumor cell lines.

CONCLUSIONS

Certain survivors are more susceptible to cisplatin-induced neurotoxicity, markedly increasing likelihood of developing numerous neuro-otological symptoms that affect quality of life. Genome-wide analysis identified genetic variation in FAM20C as a potentially important risk factor.

Automated Phenotyping Tool for Identifying Developmental Language Disorder Cases in Health Systems Data (APT-DLD): A New Research Algorithm for Deployment in Large-Scale Electronic Health Record Systems

Purpose Data mining algorithms using electronic health records (EHRs) are useful in large-scale population-wide studies to classify etiology and comorbidities (Casey et al., 2016). Here, we apply this approach to developmental language disorder (DLD), a prevalent communication disorder whose risk factors and epidemiology remain largely undiscovered. Method We first created a reliable system for manually identifying DLD in EHRs based on speech-language pathologist (SLP) diagnostic expertise. We then developed and validated an automated algorithmic procedure, called, Automated Phenotyping Tool for identifying DLD cases in health systems data (APT-DLD), that classifies a DLD status for patients within EHRs on the basis of ICD (International Statistical Classification of Diseases and Related Health Problems) codes. APT-DLD was validated in a discovery sample (N = 973) using expert SLP manual phenotype coding as a gold-standard comparison and then applied and further validated in a replication sample of N = 13,652 EHRs. Results In the discovery sample, the APT-DLD algorithm correctly classified 98% (concordance) of DLD cases in concordance with manually coded records in the training set, indicating that APT-DLD successfully mimics a comprehensive chart review. The output of APT-DLD was also validated in relation to independently conducted SLP clinician coding in a subset of records, with a positive predictive value of 95% of cases correctly classified as DLD. We also applied APT-DLD to the replication sample, where it achieved a positive predictive value of 90% in relation to SLP clinician classification of DLD. Conclusions APT-DLD is a reliable, valid, and scalable tool for identifying DLD cohorts in EHRs. This new method has promising public health implications for future large-scale epidemiological investigations of DLD and may inform EHR data mining algorithms for other communication disorders. Supplemental Material https://doi.org/10.23641/asha.12753578.

The Impact of Genetic Polymorphisms in Organic Cation Transporters on Renal Drug Disposition

A considerable number of drugs and/or their metabolites are excreted by the kidneys through glomerular filtration and active renal tubule secretion via transporter proteins. Uptake transporters in the proximal tubule are part of the solute carrier (SLC) superfamily, and include the organic cation transporters (OCTs). Several studies have shown that specific genetic polymorphisms in OCTs alter drug disposition and may lead to nephrotoxicity. Multiple single nucleotide polymorphisms (SNPs) have been reported for the OCT genes (SLC22A1, SLC22A2 and SLC22A3), which can influence the proteins’ structure and expression levels and affect their transport function. A gain-in-function mutation may lead to accumulation of drugs in renal proximal tubule cells, eventually leading to nephrotoxicity. This review illustrates the impact of genetic polymorphisms in OCTs on renal drug disposition and kidney injury, the clinical significances and how to personalize therapies to minimize the risk of drug toxicity.

Usefulness of current candidate genetic markers to identify childhood cancer patients at risk for platinum-induced ototoxicity: Results of the European PanCareLIFE cohort study

BACKGROUND

Irreversible sensorineural hearing loss is a common side effect of platinum treatment with the potential to significantly impair the neurocognitive, social and educational development of childhood cancer survivors. Genetic association studies suggest a genetic predisposition for cisplatin-induced ototoxicity. Among other candidate genes, thiopurine methyltransferase (TPMT) is considered a critical gene for susceptibility to cisplatin-induced hearing loss in a pharmacogenetic guideline. The aim of this cross-sectional cohort study was to confirm the genetic associations in a large pan-European population and to evaluate the diagnostic accuracy of the genetic markers.

METHODS

Eligibility criteria required patients to be aged less than 19 years at the start of chemotherapy, which had to include cisplatin and/or carboplatin. Patients were assigned to three phenotype categories: no, minor and clinically relevant hearing loss. Fourteen variants in eleven candidate genes (ABCC3, OTOS, TPMT, SLC22A2, NFE2L2, SLC16A5, LRP2, GSTP1, SOD2, WFS1 and ACYP2) were investigated. Multinomial logistic regression was performed to model the relationship between genetic predictors and platinum ototoxicity, adjusting for clinical risk factors. Additionally, measures of the diagnostic accuracy of the genetic markers were determined.

RESULTS

900 patients were included in this study. In the multinomial logistic regression, significant unique contributions were found from SLC22A2 rs316019, the age at the start of platinum treatment, cranial radiation and the interaction term [platinum compound]∗[cumulative dose of cisplatin]. The predictive performance of the genetic markers was poor compared with the clinical risk factors.

CONCLUSIONS

PanCareLIFE is the largest study of cisplatin-induced ototoxicity to date and confirmed a role for the polyspecific organic cation transporter SLC22A2. However, the predictive value of the current genetic candidate markers for clinical use is negligible, which puts the value of clinical factors for risk assessment of cisplatin-induced ototoxicity back into the foreground.

Testicular Cancer Survivorship

Testicular cancer (TC) is the most common cancer among men aged 18 to 39 years. It is highly curable, with a 10-year relative survival approaching 95% due to effective cisplatin-based chemotherapy. Given the increasing incidence of TC and improved survival, TC survivors (TCS) now account for approximately 4% of all US male cancer survivors. They have also become a valuable cohort for adult-onset cancer survivorship research, given their prolonged survival. Commensurately, long-term treatment-related complications have emerged as important survivorship issues. These late effects include life-threatening conditions, such as second malignant neoplasms and cardiovascular disease. Moreover, TCS can also experience hearing loss, tinnitus, neurotoxicity, nephrotoxicity, pulmonary toxicity, hypogonadism, infertility, anxiety, depression, cognitive impairment, and chronic cancer-related fatigue. Characterization of the number and severity of long-term adverse health outcomes among TCS remains critical to develop risk-stratified, evidence-based follow-up guidelines and to inform the development of preventive measures and interventions. In addition, an improved understanding of the long-term effects of TC treatment on mortality due to noncancer causes and second malignant neoplasms remains paramount. Future research should focus on the continued development of large, well-characterized clinical cohorts of TCS for lifelong follow-up. These systematic, comprehensive approaches can provide the needed infrastructure for further investigation of long-term latency patterns of various medical and psychosocial morbidities and for more in-depth studies investigating associated etiopathogenetic pathways. Studies examining premature physiologic aging may also serve as new frontiers in TC survivorship research.

Association between systemic sclerosis and risk of lung cancer: results from a pool of cohort studies and Mendelian randomization analysis

BACKGROUND

Population-based cohort studies have indicated that systemic sclerosis (SSc) may be associated with an increased risk of lung cancer. However, there are few studies that comprehensively investigate their correlation and the causal effect remains unknown.

METHODS

A systematic search of PubMed, Web of Science, Cochrane Library and Embase from the inception dates to December 1, 2019 was carried out. Meta-analysis was performed to calculate odds ratio (OR) and corresponding 95% confidence interval (CI) using random-effects models. Subgroup analyses were performed regarding gender. Two-sample Mendelian randomization (MR) was carried out with summary data from published genome-wide association studies of SSc (Neale Lab, 3871 individuals; UK Biobank, 463,315 individuals) and lung cancer (International Lung Cancer Consortium, 27,209 individuals; UK Biobank, 508,977 individuals). Study-specific estimates were summarized using inverse variance-weighted, weighted median, and MR-Egger method.

RESULTS

Through meta-analysis of 10 population-based cohort studies involving 12,218 patients, we observed a significantly increased risk of lung cancer among patients with SSc (OR 2.80, 95% CI 1.55-5.03). In accordance with subgroup analysis, male patients (OR 4.11, 95% CI 1.92-8.79) had a 1.5-fold higher lung cancer risk compared with female patients (OR 2.73, 95% CI 1.41-5.27). However, using a score of 11 SSc-related single nucleotide polymorphisms (p < 5*10^-8) as instrumental variables, the MR study did not support a causality between SSc and lung cancer (OR 1.001, 95% CI 0.929-1.100, p = 0.800). Specifically, subgroup MR analyses indicated that SSc was not associated with increased risks of non-small-cell lung cancer (OR 1.000, 95% CI 0.999-1.000, p = 0.974), including lung adenocarcinoma (OR 0.996, 95% CI 0.906-1.094, p = 0.927), squamous cell lung carcinoma (OR 1.034, 95% CI 0.937-1.140, p = 0.507), nor small-cell lung cancer (OR 1.000, 95% CI 0.999-1.000, p = 0.837).

CONCLUSIONS

This study indicated an increased risk of lung cancer among patients with SSc by meta-analysis, whereas the MR study did not support a causality between the two diseases. Further studies are warranted to investigate the factors underlying the attribution of SSc to lung cancer risk.

Pharmacogenomics as a Tool to Limit Acute and Long-Term Adverse Effects of Chemotherapeutics: An Update in Pediatric Oncology

In the past decades, new cancer treatments have been introduced in pediatric oncology leading to improvement in clinical outcomes and survival rates. However, due to inter-individual differences, some children experience severe chemotherapy-induced toxicities or a poor clinical outcome. An explanation for the diversity in response to chemotherapy is genetic variation, leading to differences in expression and activity of metabolizing and transport enzymes as well as drug targets. Pharmacogenetic testing has emerged as a promising tool to predict and limit acute and long-term adverse effects in patients. However, in pediatric oncology, limited number of patients and a considerable diversity in study results complicate the interpretation of test results and its clinical relevance. With this review, we provide an overview of new developments over the past four years regarding relevant polymorphisms related to toxicity in pediatric oncology. The following chemotherapeutics and associated toxicities are discussed: alkylating agents, anthracyclines, asparaginase, methotrexate, platinum compounds, steroids, thiopurines, topoisomerase inhibitors, and vinca alkaloids. Our review identifies several questions regarding the role of genetic variants in chemotherapy-induced toxicities. Ambiguities in the literature stem from small population sizes, differences in (statistical) interpretation and variations in sequencing technologies as well as different clinical outcome definitions. Standardization of clinical outcome data and toxicity definitions within electronic health records combined with the increased availability of genomic sequence techniques in clinical practice will help to validate these models in upcoming years.

Toxicity, risk factors and management of cisplatin-induced toxicity: A prospective study

Background and propose

Cisplatin is a cytotoxic drug that triggers several toxicities. However, nephrotoxicity and ototoxicity remain major clinical limitations. The aim of our study was to evaluate the incidence of chemotherapy toxicity induced by cisplatin and to analyze the influence of risk factors in the Tunisian population.

Methods

We performed a prospective descriptive study in a period of four months. Patients were eligible if they had pathologically confirmed malignancies and treated with cisplatin-regimen chemotherapy. Nephrotoxicity and digestive toxicity were graded according to the World Health Organization toxicity scale and ototoxicity was scored clinically according to the Common Terminology Criteria for Adverse Events (CTCAE). Multivariate logistic regression analysis was performed to evaluate the influence of clinical variables on cisplatin-induced toxicity.

Results

A total of 150 patients were included. Forty-four percent of patients developed cisplatin-regimen toxicity: 15% developed cisplatin-induced nephrotoxicity, 9% cisplatin-induced ototoxicity and 27% digestive toxicity. In the multivariate analysis, age >65 years (OR= 6.129, p = 0.010), metastatic cancer (OR = 0.171, p = 0.007) and cumulative dose (OR= 1.004 mg/m2; p = 0.042) were strong predisposing factors for CDDP-induced nephrotoxicity. The cumulative dose was an independent prognostic indicator for digestive toxicity (OR = 0.997, p = 0.002).

Conclusion

In our study, age >65 years and metastatic cancer were risk factors for cisplatin-induced nephrotoxicities. We also found the correlation between cumulative dose and nephrotoxicity or digestive toxicity.

Looking beyond the audiogram in ototoxicity associated with platinum-based chemotherapy

Introduction

Ototoxicity associated with platinum-based chemotherapy is highly prevalent and can cause detrimental consequences among cancer survivors.

Discussion

In this article, we highlight important aspects of the evaluation of ototoxicity with the aim to increase awareness of Oncologists in this regard. Standard pure tone audiometry alone is inadequate for this context. Comprehensive and consistent hearing tests should be implemented in a monitoring and surveillance program. High-frequency audiometry (10–16 kHz) is a sensitive tool in the detection of ototoxic hearing loss at onset. In addition to threshold audiometry, measures of speech comprehension (both in quiet and in noise) can add useful information in the evaluation of hearing in real-life situations. Not only hearing loss, but also tinnitus and imbalance are common in patients who receive platinum-based chemotherapy, and can cause debilitating effects upon quality of life in this population. Moreover, self-report measures associated with cochlear and vestibular handicaps can provide valuable information regarding the impact of ototoxicity.

Conclusions

It is vital to build awareness about the variety and impact of the symptoms of ototoxicity. Comprehensive evaluation of hearing status along with self-reported impact of the cochlear and vestibular handicap should be implemented in a monitoring and surveillance program for appropriate investigation and management.

Cisplatin ototoxicity in children: risk factors and its relationship with polymorphisms of DNA repair genes ERCC1, ERCC2, and XRCC1

PURPOSE

We aimed to investigate the cisplatin-related hearing toxicity and its possible relationship with polymorphic variants in DNA repair genes, ERCC1, ERCC2, and XRCC1.

METHODS

Fifty patients treated with cisplatin in the past were included in the study. There were 29 females and 21 males; mean age 13.4 ± 6.0 years). The polymorphism in DNA repair genes was studied using primer and probes in Light Cycler device after DNA isolation was carried out with PCR technique. The polymorphisms and clinical risk factors were evaluated using Chi square test and logistic regression modelling.

RESULTS

The patients had hearing loss in 44%. For ERCC1 gene, the patients with hearing loss had 50% of GG (wild type), 40.9% of AG and 9.1% of AA genotypes, while the patients without hearing loss had 28.6% of GG, 53.5% of AG, and 17.9% of AA genotypes. For ERCC2 gene, the patients with hearing loss had 18.2% of GG (wild type), 40.9% of TG, and 40.9% of TT genotypes, while the patients without hearing loss had 10.7% of GG 39.3% of TG, and 50% of TT genotypes. For XRCC1 gene, the patients with hearing loss had 18.2% of CC (wild type), 59.1% of CT, and 22.7% of TT genotypes, while the patients without hearing loss had 35.7% of CC, 50% of CT, and 14.3% of TT genotypes. There was no statistically significant association among the groups (p = 0.24).

CONCLUSION

We did not find a relationship between DNA repair gene polymorphisms and hearing toxicity of cisplatin.

Clinical and Genome-Wide Analysis of Serum Platinum Levels after Cisplatin-Based Chemotherapy

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 biexponential 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 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.

Clinical and Genetic Risk Factors for Adverse Metabolic Outcomes in North American Testicular Cancer Survivors

Background: Testicular cancer survivors (TCS) are at significantly increased risk for cardiovascular disease (CVD), with metabolic syndrome (MetS) an established risk factor. No study has addressed clinical and genetic MetS risk factors in North American TCS. Patients and Methods: TCS were aged <55 years at diagnosis and received first-line chemotherapy. Patients underwent physical examination, and had lipid panels, testosterone, and soluble cell adhesion molecule-1 (sICAM-1) evaluated. A single nucleotide polymorphism in rs523349 (5-α-reductase gene, SRD5A2), recently implicated in MetS risk, was genotyped. Using standard criteria, MetS was defined as ≥3 of the following: hypertension, abdominal obesity, hypertriglyceridemia, decreased high-density lipoprotein (HDL) cholesterol level, and diabetes. Matched controls were derived from the National Health and Nutrition Examination Survey. Results: We evaluated 486 TCS (median age, 38.1 years). TCS had a higher prevalence of hypertension versus controls (43.2% vs 30.7%; P<.001) but were less likely to have decreased HDL levels (23.7% vs 34.8%; P<.001) or abdominal obesity (28.2% vs 40.1%; P<.001). Overall MetS frequency was similar in TCS and controls (21.0% vs 22.4%; P=.59), did not differ by treatment (P=.20), and was not related to rs523349 (P=.61). For other CVD risk factors, TCS were significantly more likely to have elevated low-density lipoprotein (LDL) cholesterol levels (17.7% vs 9.3%; P<.001), total cholesterol levels (26.3% vs 11.1%; P<.001), and body mass index ≥25 kg/m² (75.1% vs 69.1%; P=.04). On multivariate analysis, age at evaluation (P<.001), testosterone level ≤3.0 ng/mL (odds ratio [OR], 2.06; P=.005), and elevated sICAM-1 level (OR_{highest vs lowest quartile}, 3.58; P=.001) were significantly associated with MetS. Conclusions and Recommendations: Metabolic abnormalities in TCS are characterized by hypertension and increased LDL and total cholesterol levels but lower rates of decreased HDL levels and abdominal obesity, signifying possible shifts in fat distribution and fat metabolism. These changes are accompanied by hypogonadism and inflammation. TCS have a high prevalence of CVD risk factors that may not be entirely captured by standard MetS criteria. Cancer treatment-associated MetS requires further characterization.

Adverse Health Outcomes in Relationship to Hypogonadism After Chemotherapy: A Multicenter Study of Testicular Cancer Survivors

BACKGROUND

This study examined the prevalence of hypogonadism, its clinical and genetic risk factors, and its relationship to adverse health outcomes (AHOs) in North American testicular cancer survivors (TCS) after modern platinum-based chemotherapy.

PATIENTS AND METHODS

Eligible TCS were <55 years of age at diagnosis and treated with first-line platinum-based chemotherapy. Participants underwent physical examinations and completed questionnaires regarding 15 AHOs and health behaviors. Hypogonadism was defined as serum testosterone levels ≤3.0 ng/mL or use of testosterone replacement therapy. We investigated the role of 2 single nucleotide polymorphisms (rs6258 and rs12150660) in the sex hormone-binding globulin (SHBG) locus implicated in increased hypogonadism risk in the general population.

RESULTS

Of 491 TCS (median age at assessment, 38.2 years; range, 18.7-68.4 years), 38.5% had hypogonadism. Multivariable binary logistic regression analysis identified hypogonadism risk factors, including age at clinical evaluation (odds ratio [OR], 1.42 per 10-year increase; P= .006) and body mass index of 25 to <30 kg/m2 (OR, 2.08; P= .011) or ≥30 kg/m2 (OR, 2.36; P= .005) compared with <25 kg/m2. TCS with ≥2 risk alleles for the SHBG SNPs had a marginally significant increased hypogonadism risk (OR, 1.45; P= .09). Vigorous-intensity physical activity appeared protective (OR, 0.66; P= .07). Type of cisplatin-based chemotherapy regimen and socioeconomic factors did not correlate with hypogonadism. Compared with TCS without hypogonadism, those with hypogonadism were more likely to report ≥2 AHOs (65% vs 51%; P= .003), to take medications for hypercholesterolemia (20.1% vs 6.0%; P<.001) or hypertension (18.5% vs 10.6%; P= .013), and to report erectile dysfunction (19.6% vs 11.9%; P= .018) or peripheral neuropathy (30.7% vs 22.5%; P= .041). A marginally significant trend for increased use of prescription medications for either diabetes (5.8% vs 2.6%; P= .07) or anxiety/depression (14.8% vs 9.3%; P= .06) was observed.

CONCLUSIONS

At a relatively young median age, more than one-third of TCS have hypogonadism, which is significantly associated with increased cardiovascular disease risk factors, and erectile dysfunction. Providers should screen TCS for hypogonadism and treat symptomatic patients.

Genetic Variants as Predictive Markers for Ototoxicity and Nephrotoxicity in Patients with Locally Advanced Head and Neck Cancer Treated with Cisplatin-Containing Chemoradiotherapy (The PRONE Study)

Ototoxicity and nephrotoxicity are potentially irreversible side effects of chemoradiotherapy with cisplatin in locally advanced head and neck cancer (LAHNC) patients. Several predictive genetic variants have been described, but as yet none in LAHNC patients. The aim of this study is to investigate genetic variants as predictors for ototoxicity and nephrotoxicity in LAHNC patients treated with cisplatin-containing chemoradiotherapy. Our prospective cohort of 92 patients was genotyped for 10 genetic variants and evaluated for their association with cisplatin-induced ototoxicity (ACYP2, COMT, TPMT and WFS1) and nephrotoxicity (OCT2, MATE and XPD). Ototoxicity was determined by patient-reported complaints as well as tone audiometrical assessments. Nephrotoxicity was defined as a decrease of ≥25% in creatinine clearance during treatment compared to baseline. A significant association was observed between carriership of the A allele for rs1872328 in the ACYP2 gene and cisplatin-induced clinically determined ototoxicity (p = 0.019), and not for ototoxicity measured by tone audiometrical assessments (p = 0.449). Carriership of a T allele for rs316019 in the OCT2 gene was significantly associated with nephrotoxicity at any time during chemoradiotherapy (p = 0.022), but not with nephrotoxicity at the end of the chemoradiotherapy. In conclusion, we showed prospectively that in LAHNC patients genetic variants in ACYP2 are significantly associated with clinically determined ototoxicity. Validation studies are necessary to prove the added value for individualized treatments plans in these patients.

Clinical and Genome-wide Analysis of Cisplatin-induced Tinnitus Implicates Novel Ototoxic Mechanisms

PURPOSE

Cisplatin, a commonly used chemotherapeutic, results in tinnitus, the phantom perception of sound. Our purpose was to identify the clinical and genetic determinants of tinnitus among testicular cancer survivors (TCS) following cisplatin-based chemotherapy.

EXPERIMENTAL DESIGN

TCS (n = 762) were dichotomized to cases (moderate/severe tinnitus; n = 154) and controls (none; n = 608). Logistic regression was used to evaluate associations with comorbidities and SNP dosages in genome-wide association study (GWAS) following quality control and imputation (covariates: age, noise exposure, cisplatin dose, genetic principal components). Pathway over-representation tests and functional studies in mouse auditory cells were performed.

RESULTS

Cisplatin-induced tinnitus (CisIT) significantly associated with age at diagnosis (P = 0.007) and cumulative cisplatin dose (P = 0.007). CisIT prevalence was not significantly greater in 400 mg/m²-treated TCS compared with 300 (P = 0.41), but doses >400 mg/m² (median 580, range 402-828) increased risk by 2.61-fold (P < 0.0001). CisIT cases had worse hearing at each frequency (0.25-12 kHz, P < 0.0001), and reported more vertigo (OR = 6.47; P < 0.0001) and problems hearing in a crowd (OR = 8.22; P < 0.0001) than controls. Cases reported poorer health (P < 0.0001) and greater psychotropic medication use (OR = 2.4; P = 0.003). GWAS suggested a variant near OTOS (rs7606353, P = 2 × 10^-6) and OTOS eQTLs were significantly enriched independently of that SNP (P = 0.018). OTOS overexpression in HEI-OC1, a mouse auditory cell line, resulted in resistance to cisplatin-induced cytotoxicity. Pathway analysis implicated potassium ion transport (q = 0.007).

CONCLUSIONS

CisIT associated with several neuro-otological symptoms, increased use of psychotropic medication, and poorer health. OTOS, expressed in the cochlear lateral wall, was implicated as protective. Future studies should investigate otoprotective targets in supporting cochlear cells.

The genetic vulnerability to cisplatin ototoxicity: a systematic review

Ototoxicity is one of the major side-effects of platinum-based chemotherapy, in particular cisplatin (cis-diammine dichloroplatinum II). To our knowledge, no systematic review has previously provided a quantitative summary estimate of the impact of genetics upon the risk of developing hearing loss. We searched Embase, Medline, ASSIA, Pubmed, Scopus, and Web of Science, for studies documenting the genetic risk of ototoxicity in patients with cancer treated with cisplatin. Titles/abstracts and full texts were reviewed for inclusion. Meta-analytic estimates of risk (Odds Ratio) from the pooled data were calculated for studies that have been repeated twice or more. The search identified 3891 papers, of which 30 were included. The majority were retrospective (44%), ranging from n = 39 to n = 317, some including only patients younger than 25 years of age (33%), and some on both genders (80%). The most common cancers involved were osteosarcoma (53%), neuroblastoma (37%), prostate (17%) and reproductive (10%). Most studies performed genotyping, though only 5 studies performed genome-wide association studies. Nineteen single-nucleotide polymorphisms (SNPs) from 15 genes were repeated more than twice. Meta-analysis of group data indicated that rs1872328 on ACYP2, which plays a role in calcium homeostasis, increases the risk of ototoxicity by 4.61 (95% CI: 3.04-7.02; N = 696, p < 0.0001) as well as LRP2 rs4668123 shows a cumulated Odds Ratio of 3.53 (95% CI: 1.48-8.45; N = 118, p = 0.0059), which could not be evidenced in individual studies. Despite the evidence of heterogeneity across studies, these meta-analytic results from 30 studies are consistent with a view of a genetic predisposition to platinum-based chemotherapy mediated ototoxicity. These new findings are informative and encourage the genetic screening of cancer patients in order to identify patients with greater vulnerability of developing hearing loss, a condition having a potentially large impact on quality of life. More studies are needed, with larger sample size, in order to identify additional markers of ototoxic risk associated with platinum-based chemotherapy and investigate polygenic risks, where multiple markers may exacerbate the side-effects.

Role of Germline Genetics in Identifying Survivors at Risk for Adverse Effects of Cancer Treatment

The growing population of cancer survivors often faces adverse effects of treatment, which have a substantial impact on morbidity and mortality. Although certain adverse effects are thought to have a significant heritable component, much work remains to be done to understand the role of germline genetic factors in the development of treatment-related toxicities. In this article, we review current understanding of genetic susceptibility to a range of adverse outcomes among cancer survivors (e.g., fibrosis, urinary and rectal toxicities, ototoxicity, chemotherapy-induced peripheral neuropathy, subsequent malignancies). Most previous research has been narrowly focused, investigating variation in candidate genes and pathways such as drug metabolism, DNA damage and repair, and inflammation. Few of the findings from these earlier candidate gene studies have been replicated in independent populations. Advances in understanding of the genome, improvements in technology, and reduction in laboratory costs have led to recent genome-wide studies, which agnostically interrogate common and/or rare variants across the entire genome. Larger cohorts of patients with homogeneous treatment exposures and systematic ascertainment of well-defined outcomes as well as replication in independent study populations are essential aspects of the study design and are increasingly leading to the discovery of variants associated with each of the adverse outcomes considered in this review. In the long-term, validated germline genetic associations hold tremendous promise for more precisely identifying patients at highest risk for developing adverse treatment effects, with implications for frontline therapy decision-making, personalization of long-term follow-up guidelines, and potential identification of targets for prevention or treatment of the toxicity.

Genetic and Modifiable Risk Factors Contributing to Cisplatin-induced Toxicities

Effective administration of traditional cytotoxic chemotherapy is often limited by off-target toxicities. This clinical dilemma is epitomized by cisplatin, a platinating agent, which 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.

Testicular cancer

Testicular cancer is the most common malignancy among men between 14 and 44 years of age, and its incidence has risen over the past two decades in Western countries. Both genetic and environmental factors contribute to the development of testicular cancer, for which cryptorchidism is the most common risk factor. Progress has been made in our understanding of the disease since the initial description of carcinoma in situ of the testis in 1972 (now referred to as germ cell neoplasia in situ), which has led to improved treatment options. The combination of surgery and cisplatin-based chemotherapy has resulted in a cure rate of >90% in patients with testicular cancer, although some patients become refractory to chemotherapy or have a late relapse; an improved understanding of the molecular determinants underlying tumour sensitivity and resistance may lead to the development of novel therapies for these patients. This Primer provides an overview of the biology, epidemiology, diagnosis and current treatment guidelines for testicular cancer, with a focus on germ cell tumours. We also outline areas for future research and what to expect in the next decade for testicular cancer.

Phenotype-Specific Enrichment of Mendelian Disorder Genes near GWAS Regions across 62 Complex Traits

Although recent studies provide evidence for a common genetic basis between complex traits and Mendelian disorders, a thorough quantification of their overlap in a phenotype-specific manner remains elusive. Here, we have quantified the overlap of genes identified through large-scale genome-wide association studies (GWASs) for 62 complex traits and diseases with genes containing mutations known to cause 20 broad categories of Mendelian disorders. We identified a significant enrichment of genes linked to phenotypically matched Mendelian disorders in GWAS gene sets; of the total 1,240 comparisons, a higher proportion of phenotypically matched or related pairs (n = 50 of 92 [54%]) than phenotypically unmatched pairs (n = 27 of 1,148 [2%]) demonstrated significant overlap, confirming a phenotype-specific enrichment pattern. Further, we observed elevated GWAS effect sizes near genes linked to phenotypically matched Mendelian disorders. Finally, we report examples of GWAS variants localized at the transcription start site or physically interacting with the promoters of genes linked to phenotypically matched Mendelian disorders. Our results are consistent with the hypothesis that genes that are disrupted in Mendelian disorders are dysregulated by non-coding variants in complex traits and demonstrate how leveraging findings from related Mendelian disorders and functional genomic datasets can prioritize genes that are putatively dysregulated by local and distal non-coding GWAS variants.