The Sound of Silence: A Proxy for Platinum Toxicity

Transition metals in angiogenesis - A narrative review

The aim of this paper is to offer a narrative review of the literature regarding the influence of transition metals on angiogenesis, excluding lanthanides and actinides. To our knowledge there are not any reviews up to date offering such a summary, which inclined us to write this paper. Angiogenesis describes the process of blood vessel formation, which is an essential requirement for human growth and development. When the complex interplay between pro- and antiangiogenic mediators falls out of balance, angiogenesis can quickly become harmful. As it is so fundamental, both its inhibition and enhancement take part in various diseases, making it a target for therapeutic treatments. Current methods come with limitations, therefore, novel agents are constantly being researched, with metal agents offering promising results. Various transition metals have already been investigated in-depth, with studies indicating both pro- and antiangiogenic properties, respectively. The transition metals are being applied in various formulations, such as nanoparticles, complexes, or scaffold materials. Albeit the increasing attention this field is receiving, there remain many unanswered questions, mostly regarding the molecular mechanisms behind the observed effects. Notably, approximately half of all the transition metals have not yet been investigated regarding potential angiogenic effects. Considering the promising results which have already been established, it should be of great interest to begin investigating the remaining elements whilst also further analyzing the established effects.

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.

Speech perception 30 years after cisplatin-based chemotherapy in adults: limited clinical relevance of long-term ototoxicity?

BACKGROUND

Cisplatin-based chemotherapy (CBCT) can cause high-frequency hearing loss, but little is known about the development and clinical relevance of this hearing loss in survivors of adult-onset cancer with very long-term follow-up. This case-control study investigates hearing and speech perception both in quiet and with background noise 30-years after CBCT.

PATIENTS AND METHODS

One-hundred-and-one patients (Cases) who received CBCT for testicular cancer between 1980 and 1994 were assessed with pure-tone audiometry (.125 - 8 kHz) and speech perception tests including hearing in noise test (HINT). Self-reported hearing and tinnitus was scored by participants. Results were compared with 30 age-matched controls.

RESULTS

The median age of Cases and Controls was 60 (46 - 83) and 61 years (51 - 74), respectively. The median observation time for Cases was 30 years (22 - 37). Compared with Controls, Cases had 8 and 19 dB worse age-adjusted high-frequency hearing at 6 and 8 kHz, respectively (p <.05), while thresholds at lower frequencies did not differ. All but four Cases reached 100% speech perception with basic speech audiometry. There was no difference between Cases and Controls in speech perception neither in quiet nor with both speech and background noise from the front, although the within-group variance was greater among Cases. Cases scored slightly worse with speech from front and noise from either side. Self-reported hearing loss (both hearing loss in general and specifically with background noise), and tinnitus were about three times more common among Cases compared with Controls.

CONCLUSIONS

Cisplatin causes high-frequency hearing loss, but speech perception tests performed both in quiet and in background noise 30 years post-treatment indicate that the clinical relevance is limited for most patients. Few patients develop severe hearing loss that requires rehabilitation but it is important to identify these patients. Self-reported hearing loss and tinnitus were more common among Cases compared with Controls.

Topic Modeling for Analyzing Patients' Perceptions and Concerns of Hearing Loss on Social Q&A Sites: Incorporating Patients' Perspective

Hearing loss is the most common human sensory deficit, affecting normal communication. Recently, patients with hearing loss or at risk of hearing loss are increasingly turning to the online health community for health information and support. Information on health-related topics exchanged on the Internet is a useful resource to examine patients' informational needs. The ability to understand the patients' perspectives on hearing loss is critical for health professionals to develop a patient-centered intervention. In this paper, we apply Latent Dirichlet Allocation (LDA) on electronic patient-authored questions on social question-and-answer (Q&A) sites to identify patients' perceptions, concerns, and needs on hearing loss. Our results reveal 21 topics, which are both representative and meaningful, and mostly correspond to sub-fields established in hearing science research. The latent topics are classified into five themes, which include "sudden hearing loss", "tinnitus", "noise-induced hearing loss", "hearing aids", "dizziness", "curiosity about hearing loss", "otitis media" and "complications of disease". Our topic analysis of patients' questions on the topic of hearing loss allows achieving a thorough understanding of patients' perspectives, thereby leading to better development of the patient-centered intervention.

The Relationship Between Cisplatin-related and Age-related Hearing Loss During an Extended Follow-up

OBJECTIVES

Cisplatin-related hearing loss (HL) is claimed to progress after treatment. This controlled longitudinal study with extended follow-up investigates HL in testicular cancer survivors (TCSs) after cisplatin-based chemotherapy (CBCT).

STUDY DESIGN

Controlled longitudinal study.

METHODS

Eighty-two TCSs treated with CBCT between 1980 and 1994 in Norway participated in two surveys (S1/S3), including pure-tone audiograms (0.125-8 kHz) and self-reported HL, 12 and 31 years after treatment, respectively. Hearing thresholds were age-adjusted based on age-matched hearing thresholds from the general population (controls). Hearing loss was defined as thresholds >20 dB at any frequency.

RESULTS

Between the two surveys, the prevalence of high-frequency HL (4, 6, and 8 kHz) increased from 73% to 94% but approached those of the aging general population after age adjustment. In TCSs aged >40 years at first survey, HL at the subsequent survey equaled that of controls. Self-reported HL increased from seven (9%) at S1 to 20 (26%) at S3. At S1, age-adjusted HL was identified in all (seven) TCSs reporting decreased hearing whereas at S3, hearing thresholds did not differ from controls in seven out of 20 patients reporting HL.

CONCLUSION

CBCT-related ototoxicity causes high-frequency HL, but in contrast to reports from follow-up studies from the first post-treatment decade, no major progression was found beyond the first post-treatment decade for frequencies 0.125-8 kHz. Importantly, with extended follow-up, hearing thresholds of patients approach those of the general population, possibly due to a less-than-additive effect with age-related hearing loss (ARHL) in CBCT-treated patients. Age-and sex-matching is strongly advised in long-term follow-up of CBCT-related ototoxicity. Specificity for detecting ototoxicity with self-reported questionnaires decreases with extended follow-up.

LEVEL OF EVIDENCE

3 Laryngoscope, 130:E515-E523, 2020.

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.

Hearing loss before and after cisplatin-based chemotherapy in testicular cancer survivors: a longitudinal study

BACKGROUND

Hearing loss is a well-known long-term effect after cisplatin-based chemotherapy (CBCT) in testicular cancer survivors (TCS), but longitudinal data are sparse. We evaluate hearing loss and the impact of age in TCS treated with CBCT in this longitudinal study.

MATERIAL AND METHODS

Forty-six TCS treated with CBCT 1980-1994 with audiograms (0.25-8 kHz) pre-chemotherapy (PRE) and at a follow-up survey (SURV) after median 10 years were included (cases). Audiograms at SURV from 46 age-matched TCS without CBCT were included as controls. Linear regression was performed to evaluate predictors for change in the hearing threshold level (HTL) from PRE to SURV. Two definitions of a audiogram-defined hearing loss was applied if: (1) mean HTL for both ears exceeded 20 dB at any frequency 0.25-8 kHz (American Speech-Language-Hearing Association (ASHA) definition) and (2) average HTL for the frequencies 0.5, 1, 2 and 4 kHz exceeded 20 dB (WHO-M4 definition). Self-reported hearing impairment (SURV) was assessed by a questionnaire.

RESULTS

Age and cisplatin dose was significantly associated with a greater change in HTL for the frequencies 2-8 kHz. For the 8 kHz frequency, each 100 mg increase in cumulative cisplatin dose was associated with a deterioration of 3.6 dB (95% CI 1.8-5.3, p < .001). The prevalence of hearing loss (ASHA) among cases was 33% PRE, 70% at SURV and 65% among controls at SURV (cases vs. controls, p = .66). According to M4, the prevalence of hearing loss among cases was 6.5% PRE, 13% at SURV and 2.2% among controls at SURV (cases vs. controls, p = .049). Twenty-nine percent of cases, and 33% of controls (p = .70) reported hearing impairment at SURV.

CONCLUSION

Cisplatin is associated with a hearing loss particularly at higher frequencies. Age appear to be an important factor for hearing loss regardless of treatment. The ASHA definition overestimates the hearing problem.

Preparation of PGA-PAE-Micelles for Enhanced Antitumor Efficacy of Cisplatin

Poly-γ-l-glutamic acid (PGA) is an outstanding drug carrier candidate owning to its excellent biodegradability and biocompatibility. The PGA carrier may shield toxic drugs from the body and enable the delivery of poorly soluble or unstable drugs and thereby minimize the side effects and improve drug efficacy. However, the limitation of PGA as a drug carrier is low drug loading efficiency (DLE), which is usually below 30%. In this study, we reported a chemical modification method using l-phenylalanine ethyl ester (PAE). PGA-PAE construct was amphiphilic, which could form micelles in aqueous solution. Cisplatin (CDDP), a commonly used chemotherapy drug whose side effect is well-known, was used as a model molecule to test the drug-loading efficiency of PGA-PAE. In this paper, two sizes of CDDP-loaded PGA-PAE micelles (M(Pt)-1 and M(Pt)-2) were prepared, the average diameter of M(Pt)-1 was 106 ± 6 nm and M(Pt)-2 was 210 ± 9 nm. The DLE of M(Pt)-1 and M(Pt)-2 was 52.8 ± 2.2 and 55.8 ± 1.2%, respectively. Both exhibited excellent biocompatibility, stability, and drug-retaining capability in physiological condition. The in vitro accumulative drug-releasing profile, IC₅₀ for different tumor cell lines HeLa, A549, and HCCC9810, and in vivo pharmacokinetics were similar between these two micelles; however, M(Pt)-1 showed higher tumor tissue retention and longer efficient cancer cell internalization time (up to 20 d). Our results suggested PGA-PAE micelle carriers reduced the toxicity of CDDP and its size at around 100 nm was the better for CDDP high-efficacy.

Cumulative Burden of Morbidity Among Testicular Cancer Survivors After Standard Cisplatin-Based Chemotherapy: A Multi-Institutional Study

Purpose In this multicenter study, we evaluated the cumulative burden of morbidity (CBM) among > 1,200 testicular cancer survivors and applied factor analysis to determine the co-occurrence of adverse health outcomes (AHOs). Patients and Methods Participants were ≤ 55 years of age at diagnosis, finished first-line chemotherapy ≥ 1 year previously, completed a comprehensive questionnaire, and underwent physical examination. Treatment data were abstracted from medical records. A CBM score encompassed the number and severity of AHOs, with ordinal logistic regression used to assess associations with exposures. Nonlinear factor analysis and the nonparametric dimensionality evaluation to enumerate contributing traits procedure determined which AHOs co-occurred. Results Among 1,214 participants, approximately 20% had a high (15%) or very high/severe (4.1%) CBM score, whereas approximately 80% scored medium (30%) or low/very low (47%). Increased risks of higher scores were associated with four cycles of either ifosfamide, etoposide, and cisplatin (odds ratio [OR], 1.96; 95% CI, 1.04 to 3.71) or bleomycin, etoposide, and cisplatin (OR, 1.44; 95% CI, 1.04 to 1.98), older attained age (OR, 1.18; 95% CI, 1.10 to 1.26), current disability leave (OR, 3.53; 95% CI, 1.57 to 7.95), less than a college education (OR, 1.44; 95% CI, 1.11 to 1.87), and current or former smoking (OR, 1.28; 95% CI, 1.02 to 1.63). CBM score did not differ after either chemotherapy regimen ( P = .36). Asian race (OR, 0.41; 95% CI, 0.23 to 0.72) and vigorous exercise (OR, 0.68; 95% CI, 0.52 to 0.89) were protective. Variable clustering analyses identified six significant AHO clusters (χ² P < .001): hearing loss/damage, tinnitus (OR, 16.3); hyperlipidemia, hypertension, diabetes (OR, 9.8); neuropathy, pain, Raynaud phenomenon (OR, 5.5); cardiovascular and related conditions (OR, 5.0); thyroid disease, erectile dysfunction (OR, 4.2); and depression/anxiety, hypogonadism (OR, 2.8). Conclusion Factors associated with higher CBM may identify testicular cancer survivors in need of closer monitoring. If confirmed, identified AHO clusters could guide the development of survivorship care strategies.

Predicting Cardiovascular Disease Among Testicular Cancer Survivors After Modern Cisplatin-based Chemotherapy: Application of the Framingham Risk Score

BACKGROUND

Testicular cancer survivors (TCSs) are at increased risk of cardiovascular disease (CVD) after cisplatin-based chemotherapy (CBCT). Identifying at-risk survivors would allow early intervention, but risk prediction tools such as the Framingham Risk Score (FRS) have not been applied to TCSs given modern chemotherapy.

METHODS

TCSs > 1 year post-CBCT were evaluated. Associations between FRS and clinical, socioeconomic, and lifestyle measures and treatment regimen (4 cycles, etoposide and cisplatin [EP × 4]); 3 or 4 cycles, bleomycin plus EP (BEP × 3, BEP × 4) were analyzed with general linear multivariable models. Controls from the National Health and Nutrition Examination Survey were matched 1:1 to TCSs by age, race, and education with differences in mean FRS evaluated with 2-sided t tests.

RESULTS

Of 787 TCSs (median age, 37.3 years; median follow-up, 4.2 years), 284, 342, and 161 received EP × 4, BEP × 3, or BEP × 4, respectively. TCSs had higher median systolic blood pressure (126 vs. 119 mm Hg; P < .001), but fewer were smokers (8.4% vs. 28.2%; P < .001) than controls. In multivariable analysis, no significant differences in FRS between EP × 4, BEP × 3, and BEP × 4 were observed, but less than college education (P < .001) and lack of vigorous exercise (P = .006) were associated with higher FRS. Mean FRS did not differ between TCSs and controls (6.8% vs. 7.3%; P = .67).

CONCLUSION

This is the first study to apply the office-based FRS to TCSs. Chemotherapy regimen (BEP × 3 vs. EP × 4) was not associated with FRS, but less educated and less vigorously active patients had higher FRS, and present a high-risk subgroup for intense follow-up and counseling.

Long-term toxicity of cisplatin in germ-cell tumor survivors

CONTEXT

Testicular germ-cell tumors (GCT) are highly curable. A multidisciplinary approach, including cisplatin-based chemotherapy has resulted in cure in the majority of patients with GCT. Thus, the life expectancy of survivors will extend to many decades post-diagnosis. Late treatment toxicities associated with cisplatin-based chemotherapy may impact their future health.

OBJECTIVE

To systematically evaluate evidence regarding the long-term toxicity of cisplatin in GCT survivors.

EVIDENCE ACQUISITION

We carried out a critical review of PubMed/Medline in February 2017 according to the Preferred Reporting Items for Systematic Review and Meta-analysis (PRISMA) statement. Identified reports were reviewed according to the Consolidated Standards of Reporting Trials (CONSORT) criteria. Eighty-three publications were selected for inclusion in this analysis.

EVIDENCE SYNTHESIS

Included reports evaluated long-term toxicities of cisplatin-based chemotherapy in GCT survivors. Studies reporting neuro- and ototoxicity, secondary malignancies, cardiovascular, renal and pulmonary toxicities, hypogonadism and infertility were found. Seven studies (8%) reported genetic underpinnings of long-term toxicities and 3 (4%) and 14 (19%) studies correlated long-term toxicities with circulating platinum levels and cumulative dose of cisplatin, respectively. Significant risks for long-term toxicities associated with cisplatin and platinum-based regimens were reported. The cumulative dose of cisplatin and circulating platinum were reported as risk factors. Several single-nucleotide polymorphisms identified patients susceptible to cisplatin compared with wild-type individuals.

CONCLUSIONS

GCT survivors cured with cisplatin-based chemotherapy are at risk for long-term side-effects. Detection of single-nucleotide polymorphisms could be a valuable tool for predicting long-term toxicities.

PATIENT SUMMARY

Herein, this article summarizes the available evidence of long-term toxicity of cisplatin-based chemotherapy in GCT survivors and provide insights from Indiana University.

Multi-Institutional Assessment of Adverse Health Outcomes Among North American Testicular Cancer Survivors After Modern Cisplatin-Based Chemotherapy

Purpose To provide new information on adverse health outcomes (AHOs) in testicular cancer survivors (TCSs) after four cycles of etoposide and cisplatin (EPX4) or three or four cycles of bleomycin, etoposide, cisplatin (BEPX3/BEPX4). Methods Nine hundred fifty-two TCSs > 1 year postchemotherapy underwent physical examination and completed a questionnaire. Multinomial logistic regression estimated AHOs odds ratios (ORs) in relation to age, cumulative cisplatin and/or bleomycin dose, time since chemotherapy, sociodemographic factors, and health behaviors. Results Median age at evaluation was 37 years; median time since chemotherapy was 4.3 years. Chemotherapy consisted largely of BEPX3 (38.2%), EPX4 (30.9%), and BEPX4 (17.9%). None, one to two, three to four, or five or more AHOs were reported by 20.4%, 42.0%, 25.1%, and 12.5% of TCSs, respectively. Median number after EPX4 or BEPX3 was two (range, zero to nine and zero to 11, respectively; P > .05) and two (range, zero to 10) after BEPX4. When comparing individual AHOs for EPX4 versus BEPX3, Raynaud phenomenon (11.6% v 21.4%; P < .01), peripheral neuropathy (29.2% v 21.4%; P = .02), and obesity (25.5% v 33.0%; P = .04) differed. Larger cumulative bleomycin doses (OR, 1.44 per 90,000 IU) were significantly associated with five or more AHOs. Increasing age was a significant risk factor for one to two, three to four, or five or more AHOs versus zero AHOs (OR, 1.22, 1.50, and 1.87 per 5 years, respectively; P < .01); vigorous physical activity was protective (OR, 0.62, 0.51, and 0.41, respectively; P < .05). Significant risk factors for three to four and five or more AHOs included current (OR, 3.05 and 3.73) or former (OR, 1.61 and 1.76) smoking ( P < .05). Self-reported health was excellent/very good in 59.9% of TCSs but decreased as AHOs increased ( P < .001). Conclusion Numbers of AHOs after EPX4 or BEPX3 appear similar, with median follow-up of 4.3 years. A healthy lifestyle was associated with reduced number of AHOs.

Long-term ototoxicity in women after cisplatin treatment for ovarian germ cell cancer

OBJECTIVE

Evaluate long-term cisplatin-induced ototoxicity in women treated for malignant ovarian germ cell tumors (MOGCT).

METHODS

Seventy-four women treated for MOGCT in Norway (1980-2009) were analyzed: 41 had received cisplatin-based chemotherapy (CBCT) ("Cases") and 33 had no CBCT ("Controls"). Median follow-up was 15years. Hearing was assessed by pure tone audiometry and by the SCIN questionnaire. Air conduction thresholds were reported as absolute hearing thresholds and age-adjusted thresholds. Absolute and age-adjusted hearing loss were defined as thresholds of >20dB at any frequency. Tinnitus was evaluated using the Tinnitus Handicap Inventory. Serum Platinum Concentration (SPC) was determined.

RESULTS

Absolute hearing loss was identified in 21 Cases (51%) and 24 Controls (73%). After adjusting for age, only 9 Cases (22%) and 5 Controls (15%) remained. Age-adjusted hearing thresholds at 4, 6 and 8kHz were slightly but significantly higher in Cases compared to Controls. Subjective hearing loss was reported by 27% of Cases and 21% of Controls, who were significantly older. Elevated SPC values were detected up to 20years after CBCT, but SPC did not correlate significantly with age-adjusted hearing loss. The rate of tinnitus was similar in Cases and Controls.

CONCLUSION

Long-term MOGCT survivors treated with CBCT have small but significant reductions in age-adjusted hearing thresholds at 4, 6 and 8kHz versus Controls. Approximately one in four women experienced subjective hearing loss. To avoid overestimation of clinically relevant cisplatin-induced ototoxicity, absolute hearing thresholds should be age-adjusted and compared to an age-matched control group.