Cisplatin-associated neuropathy characteristics compared with those associated with other neurotoxic chemotherapy agents (Alliance A151724)

Validity of Patient-Reported Outcome Measures in Evaluating Nerve Damage Following Chemotherapy

Importance

Chemotherapy-induced peripheral neuropathy (CIPN) is a substantial adverse effect of anticancer treatments. As such, the assessment of CIPN remains critically important in both research and clinic settings.

Objective

To compare the validity of various patient-reported outcome measures (PROMs) with neurophysiological and sensory functional measures as the optimal method of CIPN assessment.

Design, Setting, and Participants

This cohort study evaluated participants treated with neurotoxic chemotherapy across 2 cohorts using a dual-study design. Participants commencing treatment were assessed prospectively at beginning of neurotoxic treatment, midtreatment, and at the end of treatment. Participants who completed treatment up to 5 years prior were assessed cross-sectionally and completed a single assessment time point. Participants were recruited from oncology centers in Australia from August 2015 to November 2022. Data analysis occurred from February to November 2023.

Exposures

Neurotoxic cancer treatment including taxanes, platinums, vinca-alkaloids, proteasome inhibitors, and thalidomide.

Main Outcomes and Measures

CIPN was assessed via PROMs (European Organization for Research and Treatment of Cancer Quality of Life Questionnaire [EORTC-CIPN20], Functional Assessment of Cancer Therapy/Gynecological Cancer Group Neurotoxicity Questionnaire (FACT/GOG-Ntx), and the patient-reported outcomes version of the Common Terminology Criteria for Adverse Events [PRO-CTCAE]), neurological and neurophysiological assessment (Total Neuropathy Score and sural and tibial compound nerve amplitudes), and sensory measures (Grating orientation, Von Frey monofilament, and 2-point discrimination tasks). Core measurement properties of CIPN outcome measures were evaluated. Convergent and known-groups validity was assessed cross-sectionally following treatment completion, and responsiveness was evaluated prospectively during treatment. Neurological, neurophysiological, and sensory outcome measure scores were compared between those who reported high and low levels of CIPN symptoms using linear regressions.

Results

A total of 1033 participants (median [IQR] age, 61 [50-59] years; 676 female [65.4%]) were recruited to this study, incorporating 1623 assessments. PROMs demonstrated best ability to accurately assess CIPN (convergent validity), especially the PRO-CTCAE composite score (r = 0.85; P < .001) and EORTC-CIPN20 (r = 0.79; P < .001). PROMS also demonstrated the best ability to discriminate between CIPN severity (known-groups validity) and to detect changes at onset of CIPN development (responsiveness), especially for EORTC-CIPN20 (d = 0.67; 95% CI, 0.52-0.83), FACT/GOG-Ntx (d = 0.65; 95% CI, 0.49-0.81) and the PRO-CTCAE (d = 0.83; 95% CI, 0.64-1.02). Other measures did not achieve threshold for convergent validity (α < 0.7). Neurophysiological and sensory measures did not demonstrate acceptable responsiveness. In regression models, neurological, neurophysiological, and sensory outcome measures were significantly impaired in participants who reported high levels of CIPN symptoms compared with those who reported low levels of CIPN symptoms.

Conclusions and Relevance

In this cohort study of 1033 cancer patients, PROMs were the only measures to satisfy all 3 core measurement property criteria (convergent validity, known-groups validity, and responsiveness). These findings suggest that adoption of PROMs in clinical practice can equip clinicians with valuable information in assessing CIPN morbidity.

Salivary toxicity from PSMA-targeted radiopharmaceuticals: What we have learned and where we are going

Clinical trials of prostate-specific membrane antigen (PSMA) targeted radiopharmaceuticals have shown encouraging results. Some agents, like lutetium-177 [177Lu]Lu-PSMA-617 ([177Lu]Lu-PSMA-617), are already approved for late line treatment of metastatic castration-resistant prostate cancer (mCRPC). Projections are for continued growth of this treatment modality; [177Lu]Lu-PSMA-617 is being studied both in earlier stages of disease and in combination with other anti-cancer therapies. Further, the drug development pipeline is deep with variations of PSMA-targeting radionuclides, including higher energy alpha particles conjugated to PSMA-honing vectors. It is safe to assume that an increasing number of patients will be exposed to PSMA-targeted radiopharmaceuticals during the course of their cancer treatment. In this setting, it is important to better understand and mitigate the most commonly encountered toxicities. One particularly vexing side effect is xerostomia. In this review, we discuss the scope of the problem, inventories to better characterize and monitor this troublesome side effect, and approaches to preserve salivary function and effectively palliate symptoms. This article aims to serve as a useful reference for prescribers of PSMA-targeted radiopharmaceuticals, while also commenting on areas of missing data and opportunities for future research.

Phytic Acid Maintains Peripheral Neuron Integrity and Enhances Survivability against Platinum-Induced Degeneration via Reducing Reactive Oxygen Species and Enhancing Mitochondrial Membrane Potential

Phytic acid (PA) has been reported to possess anti-inflammatory and antioxidant properties that are critical for neuroprotection in neuronal disorders. This raises the question of whether PA can effectively protect sensory neurons against chemotherapy-induced peripheral neuropathy (CIPN). Peripheral neuropathy is a dose-limiting side effect of chemotherapy treatment often characterized by severe and abnormal pain in hands and feet resulting from peripheral nerve degeneration. Currently, there are no effective treatments available that can prevent or cure peripheral neuropathies other than symptomatic management. Herein, we aim to demonstrate the neuroprotective effects of PA against the neurodegeneration induced by the chemotherapeutics cisplatin (CDDP) and oxaliplatin. Further aims of this study are to provide the proposed mechanism of PA-mediated neuroprotection. The neuronal protection and survivability against CDDP were characterized by axon length measurements and cell body counting of the dorsal root ganglia (DRG) neurons. A cellular phenotype study was conducted microscopically. Intracellular reactive oxygen species (ROS) was estimated by fluorogenic probe dichlorofluorescein. Likewise, mitochondrial membrane potential (MMP) was assessed by fluorescent MitoTracker Orange CMTMRos. Similarly, the mitochondria-localized superoxide anion radical in response to CDDP with and without PA was evaluated. The culture of primary DRG neurons with CDDP reduced axon length and overall neuronal survival. However, cotreatment with PA demonstrated that axons were completely protected and showed increased stability up to the 45-day test duration, which is comparable to samples treated with PA alone and control. Notably, PA treatment scavenged the mitochondria-specific superoxide radicals and overall intracellular ROS that were largely induced by CDDP and simultaneously restored MMP. These results are credited to the underlying neuroprotection of PA in a platinum-treated condition. The results also exhibited that PA had a synergistic anticancer effect with CDDP in ovarian cancer in vitro models. For the first time, PA's potency against CDDP-induced PN is demonstrated systematically. The overall findings of this study suggest the application of PA in CIPN prevention and therapeutic purposes.

Impact of pain and adverse health outcomes on long-term US testicular cancer survivors

BACKGROUND

No study has quantified the impact of pain and other adverse health outcomes on global physical and mental health in long-term US testicular cancer survivors or evaluated patient-reported functional impairment due to pain.

METHODS

Testicular cancer survivors given cisplatin-based chemotherapy completed validated surveys, including Patient-Reported Outcomes Measurement Information System v1.2 global physical and mental health, Patient-Reported Outcomes Measurement Information System pain questionnaires, and others. Multivariable linear regression examined relationships between 25 adverse health outcomes with global physical and mental health and pain-interference scores. Adverse health outcomes with a β^  of more than 2 are clinically important and reported below.

RESULTS

Among 358 testicular cancer survivors (median age = 46 years, interquartile range [IQR] = 38-53 years; median time since chemotherapy = 10.7 years, IQR = 7.2-16.0 years), median adverse health outcomes number was 5 (IQR = 3-7). A total of 12% testicular cancer survivors had 10 or more adverse health outcomes, and 19% reported chemotherapy-induced neuropathic pain. Increasing adverse health outcome numbers were associated with decreases in physical and mental health (P < .0001 each). In multivariable analyses, chemotherapy-induced neuropathic pain (β^ = -3.72; P = .001), diabetes (β^ = -4.41; P = .037), obesity (β^ = -2.01; P = .036), and fatigue (β^ = -8.58; P < .0001) were associated with worse global mental health, while being married or living as married benefited global mental health (β^ = 3.63; P = .0006). Risk factors for pain-related functional impairment included lower extremity location (β^ = 2.15; P = .04) and concomitant peripheral artery disease (β^ = 4.68; P < .001). Global physical health score reductions were associated with diabetes (β^ = -3.81; P = .012), balance or equilibrium problems (β^ = -3.82; P = .003), cognitive dysfunction (β^ = -4.43; P < .0001), obesity (β^ = -3.09; P < .0001), peripheral neuropathy score (β^ = -2.12; P < .0001), and depression (β^ = -3.17; P < .0001).

CONCLUSIONS

Testicular cancer survivors suffer adverse health outcomes that negatively impact long-term global mental health, global physical health, and pain-related functional status. Clinically important factors associated with worse physical and mental health identify testicular cancer survivors requiring closer monitoring, counseling, and interventions. Chemotherapy-induced neuropathic pain must be addressed, given its detrimental impact on patient-reported functional status and mental health 10 or more years after treatment.

G Protein-Coupled Receptors and Ion Channels Involvement in Cisplatin-Induced Peripheral Neuropathy: A Review of Preclinical Studies

Cisplatin is a platinum-based chemotherapy drug widely used to treat various solid tumours. Although it is effective in anti-cancer therapy, many patients develop peripheral neuropathy during and after cisplatin treatment. Peripheral neuropathy results from lesions or diseases in the peripheral somatosensory nervous system and is a significant cause of debilitation and suffering in patients. In recent years, preclinical studies have been conducted to elucidate the mechanisms involved in chemotherapy-induced peripheral neuropathic pain, as well as to promote new therapeutic targets since current treatments are ineffective and are associated with adverse effects. G-protein coupled receptors and ion channels play a significant role in pain processing and may represent promising targets for improving the management of cisplatin-induced neuropathic pain. This review describes the role of G protein-coupled receptors and ion channels in cisplatin-induced pain, analysing preclinical experimental studies that investigated the role of each receptor subtype in the modulation of cisplatin-induced pain.

Monoclonal Antibody Targeting CGRP Relieves Cisplatin-Induced Neuropathic Pain by Attenuating Neuroinflammation

Chemotherapy-induced neuropathic pain (CIPN) is a common side effect of antitumor chemotherapeutic agents. It describes a pathological state of pain related to the cumulative dosage of the drug, significantly limiting the efficacy of antitumor treatment. Sofas strategies alleviating CIPN still lack. Calcitonin gene-related peptide (CGRP) is a neuropeptide involved in many pathologic pains. In this study, we explored the effects of CGRP blocking on CIPN and potential mechanisms. Total dose of 20.7 mg/kg cisplatin was used to establish a CIPN mouse model. Mechanical and thermal hypersensitivity was measured using von Frey hairs and tail flick test. Western blot and immunofluorescence were utilized to evaluate the levels of CGRP and activated astrocytes in mouse spinal cord, respectively. In addition, real-time quantitative PCR (RT-qPCR) was used to detect the level of inflammatory cytokines such as IL-6, IL-1β, and NLRP3 in vitro and in vivo. There are markedly increased CGRP expression and astrocyte activation in the spinal cord of mice following cisplatin treatment. Pretreatment with a monoclonal antibody targeting CGRP (ZR8 mAb) effectively reduced cisplatin-induced mechanical hypersensitivity and thermal nociceptive sensitization and attenuated neuroinflammation as marked by downregulated expression of IL-6, IL-1β, and NLRP3 in the mice spinal cord and spleen. Lastly, ZR8 mAb does not interfere with the antitumor effects of cisplatin in tumor-bearing mice. Our findings indicate that neutralizing CGRP with monoclonal antibody could effectively alleviate CIPN by attenuating neuroinflammation. CGRP is a promising therapeutic target for CIPN.

A Novel Therapy for Cisplatin-Induced Allodynia and Dysfunctional and Emotional Impairments in Male and Female Mice

Patients undergoing chemotherapy with cisplatin (CIS) develop neuropathy in addition to other symptoms such as, anxiety, depression, muscle wasting and body weight loss. This symptomatology greatly weakens patients and may even lead to adjournment of chemotherapy. The protecting actions of molecular hydrogen in many neurological illnesses have been described, but its effect on the functional and emotional deficiencies caused by CIS has not been assessed. In C57BL/6J male and female mice injected with CIS, we examined the impact of the prophylactic treatment with hydrogen-rich water (HRW) on: (i) the tactile and cold allodynia, (ii) the deficits of grip strength and weight loss, (iii) the anxiodepressive-like behaviors and (iv) the inflammatory and oxidative reactions incited by CIS in the dorsal root ganglia (DRG) and prefrontal cortex (PFC). The results demonstrate that the mechanical allodynia and the anxiodepressive-like comportment provoked by CIS were similarly manifested in both sexes, whereas the cold allodynia, grip strength deficits and body weight loss produced by this chemotherapeutic agent were greater in female mice. Nonetheless, the prophylactic treatment with HRW prevented the allodynia and the functional and emotional impairments resulting from CIS in both sexes. This treatment also inhibited the inflammatory and oxidative responses activated by CIS in the DRG and PFC in both sexes, which might explain the therapeutic actions of HRW in male and female mice. In conclusion, this study revealed the plausible use of HRW as a new therapy for the allodynia and physical and mental impairments linked with CIS and its possible mechanism of action.

A state-of-art of underlying molecular mechanisms and pharmacological interventions/nanotherapeutics for cisplatin resistance in gastric cancer

The fourth common reason of death among patients is gastric cancer (GC) and it is a dominant tumor type in Ease Asia. One of the problems in GC therapy is chemoresistance. Cisplatin (CP) is a platinum compound that causes DNA damage in reducing tumor progression and viability of cancer cells. However, due to hyperactivation of drug efflux pumps, dysregulation of genes and interactions in tumor microenvironment, tumor cells can develop resistance to CP chemotherapy. The current review focuses on the CP resistance emergence in GC cells with emphasizing on molecular pathways, pharmacological compounds for reversing chemoresistance and the role of nanostructures. Changes in cell death mechanisms such as upregulation of pro-survival autophagy can prevent CP-mediated apoptosis that results in drug resistance. Moreover, increase in metastasis via EMT induction induces CP resistance. Dysregulation of molecular pathways such as PTEN, PI3K/Akt, Nrf2 and others result in changes in CP response of GC cells. Non-coding RNAs determine CP response of GC cells and application of pharmacological compounds with activity distinct of CP can result in sensitivity in tumor cells. Due to efficacy of exosomes in transferring bioactive molecules such as RNA and DNA molecules among GC cells, exosomes can also result in CP resistance. One of the newest progresses in overcoming CP resistance in GC is application of nanoplatforms for delivery of CP in GC therapy that they can increase accumulation of CP at tumor site and by suppressing carcinogenic factors and overcoming biological barriers, they increase CP toxicity on cancer cells.

Milnacipran Has an Antihyperalgesic Effect on Cisplatin-Induced Neuropathy

(1) Background: Milnacipran is a typical serotonin-norepinephrine reuptake inhibitor and has been shown to have analgesic effects in several pain models. However, its antihyperalgesic effect in cisplatin-induced neuropathy remains unknown. We examined the effects of intraperitoneal (IP) milnacipran on allodynia in cisplatin-induced peripheral neuropathic mice. (2) Methods: Peripheral neuropathy was induced by injecting cisplatin (2.3 mg/kg/day, IP) six times, on every other day. Saline or milnacipran (10, 30, 50 mg/kg, IP) were then administered to the neuropathic mice. We examined mechanical allodynia using von Frey hairs at preadministration and at 30, 60, 90, 120, 180, 240 min and 24 h after drug administration. We also measured the dorsal root ganglion (DRG) activating transcription factor 3 (ATF3) to confirm the analgesic effects of milnacipran. (3) Results: For the milnacipran groups, the decreased paw withdrawal thresholds to mechanical stimuli were significantly reversed when compared to the preadministration values and the values in the saline-injected control group (p < 0.0001). Milnacipran administration to cisplatin-induced peripheral neuropathic mice resulted in a significant suppression of neuronal ATF3 activation (p < 0.01). (4) Conclusions: Milnacipran given via IP injection attenuates mechanical allodynia in mouse models of cisplatin-induced poly-neuropathic pain. These effects were confirmed by significant suppression of neuronal ATF3 activation in the DRG.

Kinin B2 Receptor Mediates Cisplatin-Induced Painful Peripheral Neuropathy by Intracellular Kinase Pathways and TRPA1 Channel Sensitisation

Chemotherapy-induced peripheral neuropathy is a severe clinical problem frequently associated with cisplatin use. Although its pathophysiology is poorly understood, it is known that kinin receptors and the transient receptor potential ankyrin 1 (TRPA1) channel play a significant role in the peripheral neuropathy induced by cisplatin in rodents. However, the role of signalling pathways downstream from B₂ kinin receptors activation and sensitisation of the TRPA1 channel remains unknown in this model. The cisplatin-induced neuropathy model caused mechanical and cold allodynia in male Swiss mice. Antagonists for kinin B₂ and B₁ receptors and the TRPA1 channel attenuated the painful parameters. Local sub-nociceptive doses of kinin B₂ receptor (bradykinin) and TRPA1 channel (allyl isothiocyanate; AITC) agonists enhanced the painful parameters in cisplatin-treated mice, which their respective antagonists attenuated. Furthermore, we demonstrated the interaction between the kinin B₂ receptor and the TRPA1 channel in cisplatin-induced peripheral neuropathy since phospholipase C (PLC) and protein kinase C epsilon (PKCε) inhibitors attenuated the increase in mechanical and cold allodynia evoked by bradykinin and AITC in cisplatin-treated mice. Therefore, regulating the activation of signalling pathways downstream from the kinin B₂ receptors activation and TRPA1 channel sensitisation can mitigate the painful peripheral neuropathy decurrent of the oncology treatment with cisplatin.

An evaluation of the effect of lithium on taxane-induced neuropathy

PURPOSE

No medications are known to protect against chemotherapy-induced peripheral neuropathy (CIPN). Pre-clinical models suggest that lithium may lessen taxane-induced neuropathy. Our aim was to use clinical data to assess whether concurrent lithium usage decreased the frequency or severity of CIPN in patients receiving taxane chemotherapy.

METHODS

A retrospective analysis was performed using the electronic health record at Mayo Clinic to identify all patients prescribed concurrent lithium and paclitaxel. Four controls were matched to each case based on clinical variables. Neuropathy severity was graded from available patient and clinician reports. Rates of any neuropathy, dose reduction for CIPN, and treatment discontinuation for CIPN were compared. Conditional regression analysis was performed with propensity score matching.

RESULTS

Six patients, receiving concurrent lithium and paclitaxel, were included in the analysis, and compared to 24 control cases. A similar number of paclitaxel cycles were administered to both groups. Any neuropathy was experienced by 33% (2/6) of patients receiving lithium and 38% (9/24) patients who did not receive lithium (p = 1.000). There was no difference in neuropathy severity (p = 0.8565), rate of chemotherapy dose reduction (17% vs. 17%, p = 1.000), or treatment discontinuation (17% vs 4%, p = 0.3655) for CIPN. In the propensity score analysis, the odds ratio for developing any neuropathy was 0.63 (95% confidence interval, 0.06 to 6.96, p = 0.7079).

CONCLUSIONS

Lithium does not appear to significantly lessen the risk of neuropathy for patients receiving paclitaxel.

IMPLICATIONS FOR CANCER SURVIVORS

Targeted approaches for preventing CIPN are desperately needed. Despite sound scientific rationale, the current study did not identify neuroprotective properties of lithium.

Neuropathy, its Profile and Experimental Nerve Injury Neuropathic Pain Models: A Review

Neuropathy is a terrible disorder that has a wide range of etiologies. Drug-induced neuropathy, which happens whenever a chemical agent damages the peripheral nerve system, has been linked here to the iatrogenic creation of some drugs. It is potentially permanent and causes sensory impairments and paresthesia that typically affects the hands, feet, and stockings; motor participation is uncommon. It might appear suddenly or over time, and the long-term outlook varies. The wide range of chronic pain conditions experienced by people has been one of the main obstacles to developing new, more effective medications for the treatment of neuropathic pain. Animal models can be used to examine various neuropathic pain etiologies and symptoms. Several models investigate the peripheral processes of neuropathic pain, whereas some even investigate the central mechanisms, such as drug induce models like vincristine, cisplatin, bortezomib, or thalidomide, etc., and surgical models like sciatic nerve chronic constriction injury (CCI), sciatic nerve ligation through spinal nerve ligation (SNL), sciatic nerve damage caused by a laser, SNI (spared nerve injury), etc. The more popular animal models relying on peripheral nerve ligatures are explained. In contrast to chronic sciatic nerve contraction, which results in behavioral symptoms of less reliable stressful neuropathies, (SNI) spared nerve injury generates behavioral irregularities that are more feasible over a longer period. This review summarizes the latest methods models as well as clinical ideas concerning this mechanism. Every strongest current information on neuropathy is discussed, along with several popular laboratory models for causing neuropathy.

Animal models of chemotherapy-induced peripheral neuropathy for hematological malignancies: A review

Chemotherapy is one of the main treatments for hematologic malignancies. However, chemotherapy-induced peripheral neuropathy (CIPN) is one of the most common long-term toxic reactions in chemotherapy, and the occurrence of CIPN affects patients' quality of life and can cause interruption of chemotherapy in severe cases, thus reducing the efficacy of chemotherapy. We currently summarize the existing CIPN animal models, including the characteristics of several common animal models such as bortezomib-induced peripheral neuropathy, vincristine-induced peripheral neuropathy, and oxaliplatin-induced peripheral neuropathy. It was found that CIPN may lead to behavioral, histopathological, and neurophysiological changes inducing peripheral neuropathy. However, the mechanism of CIPN has not been fully elucidated, especially the prevention and treatment protocols need to be improved. Therefore, this review article summarizes the progress of research on CIPN animal models and the possible mechanisms and treatment of CIPN.

Pregabalin for chemotherapy-induced neuropathy: background and rationale for further study

Chemotherapy-induced neuropathy is difficult to manage, and the pain associated with neuropathy is poorly responsive to gabapentin in a randomized trial. Duloxetine is the only drug that has been found to be effective in reducing pain from chemotherapy neuropathy. In this qualitative review, the use of pregabalin for chemotherapy-induced neuropathy is discussed including the rationale and pharmacological reasons why pregabalin should be considered in a large, randomized placebo-controlled trial.

Cisplatin for cancer therapy and overcoming chemoresistance

Cisplatin spearheads the anticancer chemotherapeutics in present-day use although acute toxicity is its primary impediment factor. Among a plethora of experimental medications, a drug as effective or surpassing the benefits of cisplatin has not been discovered yet. Although Oxaliplatin is considered more superior to cisplatin, the former has been better for colorectal cancer while cisplatin is widely used for treating gynaecological cancers. Carcinoma imposes a heavy toll on mortality rates worldwide despite the novel treatment strategies and detection methods that have been introduced; nanomedicine combined with precision medicine, immunotherapy, volume-regulated anion channels, and fluorodeoxyglucose-positron emission tomography. Millions of deaths occur annually from metastatic cancers which escape early detection and the concomitant diseases caused by highly toxic chemotherapy that causes organ damage. It continues due to insufficient knowledge of the debilitative mechanisms induced by cancer biology. To overcome chemoresistance and to attenuate the adverse effects of cisplatin therapy, both in vitro and in vivo models of cisplatin-treated cancers and a few multi-centred, multi-phasic, randomized clinical trials in pursuant with recent novel strategies have been tested. They include plant-based phytochemical compounds, de novo drug delivery systems, biochemical/immune pathways, 2D and 3D cell culture models using small molecule inhibitors and genetic/epigenetic mechanisms, that have contributed to further the understanding of cisplatin's role in modulating the tumour microenvironment. Cisplatin was beneficial in cancer therapy for modulating the putative cellular mechanisms; apoptosis, autophagy, cell cycle arrest and gene therapy of micro RNAs. Specific importance of drug influx, efflux, systemic circulatory toxicity, half-maximal inhibition, and the augmentation of host immunometabolism have been identified. This review offers a discourse on the recent anti-neoplastic treatment strategies to enhance cisplatin efficacy and to overcome chemoresistance, given its superiority among other tolerable chemotherapies.

Chemotherapy-Induced Peripheral Neuropathy: Epidemiology, Pathomechanisms and Treatment

PURPOSE

This review provides an update on the current clinical, epidemiological and pathophysiological evidence alongside the diagnostic, prevention and treatment approach to chemotherapy-induced peripheral neuropathy (CIPN).

FINDINGS

The incidence of cancer and long-term survival after treatment is increasing. CIPN affects sensory, motor and autonomic nerves and is one of the most common adverse events caused by chemotherapeutic agents, which in severe cases leads to dose reduction or treatment cessation, with increased mortality. The primary classes of chemotherapeutic agents associated with CIPN are platinum-based drugs, taxanes, vinca alkaloids, bortezomib and thalidomide. Platinum agents are the most neurotoxic, with oxaliplatin causing the highest prevalence of CIPN. CIPN can progress from acute to chronic, may deteriorate even after treatment cessation (a phenomenon known as coasting) or only partially attenuate. Different chemotherapeutic agents share both similarities and key differences in pathophysiology and clinical presentation. The diagnosis of CIPN relies heavily on identifying symptoms, with limited objective diagnostic approaches targeting the class of affected nerve fibres. Studies have consistently failed to identify at-risk cohorts, and there are no proven strategies or interventions to prevent or limit the development of CIPN. Furthermore, multiple treatments developed to relieve symptoms and to modify the underlying disease in CIPN have failed.

IMPLICATIONS

The increasing prevalence of CIPN demands an objective approach to identify at-risk patients in order to prevent or limit progression and effectively alleviate the symptoms associated with CIPN. An evidence base for novel targets and both pharmacological and non-pharmacological treatments is beginning to emerge and has been recognised recently in publications by the American Society of Clinical Oncology and analgesic trial design expert groups such as ACTTION.

Chemotherapy and peripheral neuropathy

Chemotherapy-induced peripheral neurotoxicity (CIPN) is a major dose-limiting side effect of many anti-cancer agents, including taxanes, platinums, vinca alkaloids, proteasome inhibitors, immunomodulatory drugs, and antibody-drug conjugates. The resultant symptoms often persist post treatment completion and continue to impact on long-term function and quality of life for cancer survivors. At present, dose reduction remains the only strategy to prevent severe neuropathy, often leading clinicians to the difficult decision of balancing maximal treatment exposure and minimal long-lasting side effects. This review examines the clinical presentations of CIPN with each class of neurotoxic treatment, describing signs, symptoms, and long-term outcomes. We provide an update on the proposed mechanisms of nerve damage and review current data on clinical and genetic risk factors contributing to CIPN development. We also examine recent areas of research in the treatment and prevention of CIPN, with specific focus on current clinical trials and consensus recommendations for CIPN management.

Grape seed proanthocyanidin extract ameliorates cisplatin-induced testicular apoptosis via PI3K/Akt/mTOR and endoplasmic reticulum stress pathways in rats

Testicular toxicity is an adverse reaction of the effective chemotherapy drug cisplatin (CIS). Our previous study found that grape seed proanthocyanidin extract (GSPE) had a protective effect on CIS-induced testicular toxicity. However, the protective mechanism of GSPE against CIS-induced testicular toxicity remains unknown. In this study, we aimed to investigate whether GSPE can reduce CIS-induced testicular toxicity and its potential mechanism in rats. The results showed that GSPE ameliorated CIS-induced the apoptosis of testicular cells and inhibited the protein levels of Bad, Cyt c, caspase-9, caspase-3, caspase-12, GRP78, CHOP, IRE1α, p-IRE1α, XBP-1S, PERK, p-PERK, eIF2α, and p-eIF2α. Besides, GSPE reversed the downregulation of PI3K, p-PI3K, Akt, p-Akt, mTOR, and p-mTOR protein expression induced by CIS. These results indicated that GSPE can improve CIS-induced testicular cells apoptosis via activating PI3K/Akt/mTOR and inhibiting Bad/Cyt c/caspase-9/caspase-3 pathways. And GSPE relieved endoplasmic reticulum stress-mediated apoptosis via inhibiting PREK/eIF2α and IRE1α/XBP-1S/caspase-12 pathways. In conclusion, the evidence suggested that GSPE can act as a protective agent against testicular toxicity induced by CIS. PRACTICAL APPLICATIONS: Testicular toxicity was a well-known adverse effect of cisplatin (CIS) in cancer treatment. Grape seed proanthocyanidin extract (GSPE) has been reported to serve as one of the most therapeutic potentials agents. In present study, we explored the regulatory effects of GSPE on the apoptosis induced by CIS, which involved testicular apoptosis mechanisms in rats. Our results indicated that CIS caused testicular toxicity via PI3K/AKT/mTOR and ERS mediated apoptosis pathway in rats. This toxicity was attenuated by GSPE treatment via activated PI3K/Akt/mTOR pathway, and inhibiting Bad/CytC/caspase-9/caspase-3 as well as PREK/eIF2α, IRE1α/XBP-1S/caspase-12 pathways. Our findings suggest that GSPE may be a novel protective agent against testicular toxicity induced by CIS.

Corneal nerve changes following treatment with neurotoxic anticancer drugs

Survival rates of cancer has improved with the development of anticancer drugs including systemic chemotherapeutic agents. However, long-lasting side effects could impact treated patients. Neurotoxic anticancer drugs are specific agents which cause chemotherapy-induced peripheral neuropathy (CIPN), a debilitating condition that severely deteriorates quality of life of cancer patients and survivors. The ocular surface is also prone to neurotoxicity but investigation into the effects of neurotoxic chemotherapy on the ocular surface has been more limited compared to other systemic etiologies such as diabetes. There is also no standardized protocol for CIPN diagnosis with an absence of a reliable, objective method of observing nerve damage structurally. As the cornea is the most densely innervated region of the body, researchers have started to focus on corneal neuropathic changes that are associated with neurotoxic chemotherapy treatment. In-vivo corneal confocal microscopy enables rapid and objective structural imaging of ocular surface microscopic structures such as corneal nerves, while esthesiometers provide means of functional assessment by examining corneal sensitivity. The current article explores the current guidelines and gaps in our knowledge of CIPN diagnosis and the potential role of in-vivo corneal confocal microscopy as a diagnostic or prognostic tool. Corneal neuropathic changes with neurotoxic anticancer drugs from animal research progressing through to human clinical studies are also discussed, with a focus on how these data inform our understanding of CIPN.

Impact of Chemotherapy-Induced Peripheral Neuropathy on Quality of Life in Patients with Advanced Lung Cancer Receiving Platinum-Based Chemotherapy

Chemotherapy-induced peripheral neuropathy (CIPN) is a common adverse effect of neurotoxic anticancer drugs that may affect quality of life (QoL). Purpose: The purposes of this study were to: assess the levels of CIPN, anxiety, depression, CIPN–related QoL, and general QoL; and identify the factors related to CIPN–related QoL and general QoL in patients with advanced lung cancer (LC) receiving platinum-based chemotherapy. This cross-sectional study examined patients with advanced LC who received platinum-based chemotherapy from the thoracic oncology inpatient wards of a medical center in northern Taiwan. Structured questionnaires were used to measure patients’ CIPN (European Organization for Research and Treatment of Cancer quality of life questionnaire–chemotherapy–induced peripheral neuropathy 20), anxiety (Hospital Anxiety and Depression Scale Depression Scale [HADS]), depression (HADS), CIPN-related QoL (Functional Assessment of Cancer Therapy /Gynecologic Oncology Group-Neurotoxicity subscale [FACT/GOG–Ntx]), and general QoL (Functional Assessment of Cancer Therapy–General Input [FACT-G]). Of 93 patients with advanced LC, 53.8% reported CIPN–sensory impairment and 47.3% reported CIPN–motor impairment. The most common CIPN symptoms were difficulty getting or maintaining an erection (only for men > 65 years) and difficulty in climbing stairs or getting up out of a chair. Poor CIPN–related QoL (FACT/GOG–Ntx) was associated with more CIPN–sensory and more CIPN–motor impairment. Poor general QoL (FACT-G) was associated with a higher level of depression, a higher level of anxiety, and receipt of more chemotherapy cycles. More than half of LC patients report impairment related to CIPN, calling for holistic treatment to improve QoL.

Exploring the Potential Role of the Gut Microbiome in Chemotherapy-Induced Neurocognitive Disorders and Cardiovascular Toxicity

Chemotherapy, targeting not only malignant but also healthy cells, causes many undesirable side effects in cancer patients. Due to this fact, long-term cancer survivors often suffer from late effects, including cognitive impairment and cardiovascular toxicity. Chemotherapy damages the intestinal mucosa and heavily disrupts the gut ecosystem, leading to gastrointestinal toxicity. Animal models and clinical studies have revealed the associations between intestinal dysbiosis and depression, anxiety, pain, impaired cognitive functions, and cardiovascular diseases. Recently, a possible link between chemotherapy-induced gut microbiota disruption and late effects in cancer survivors has been proposed. In this review, we summarize the current understanding of preclinical and clinical findings regarding the emerging role of the microbiome and the microbiota-gut-brain axis in chemotherapy-related late effects affecting the central nervous system (CNS) and heart functions. Importantly, we provide an overview of clinical trials evaluating the relationship between the gut microbiome and cancer survivorship. Moreover, the beneficial effects of probiotics in experimental models and non-cancer patients with neurocognitive disorders and cardiovascular diseases as well as several studies on microbiota modulations via probiotics or fecal microbiota transplantation in cancer patients are discussed.