Liability of the voltage-gated potassium channel KCNN3 repeat polymorphism to acute oxaliplatin-induced peripheral neurotoxicity

Oxaliplatin-induced peripheral neurotoxicity in colorectal cancer patients: mechanisms, pharmacokinetics and strategies

Oxaliplatin-based chemotherapy is a standard treatment approach for colorectal cancer (CRC). However, oxaliplatin-induced peripheral neurotoxicity (OIPN) is a severe dose-limiting clinical problem that might lead to treatment interruption. This neuropathy may be reversible after treatment discontinuation. Its complicated mechanisms are related to DNA damage, dysfunction of voltage-gated ion channels, neuroinflammation, transporters, oxidative stress, and mitochondrial dysfunction, etc. Several strategies have been proposed to diminish OIPN without compromising the efficacy of adjuvant therapy, namely, combination with chemoprotectants (such as glutathione, Ca/Mg, ibudilast, duloxetine, etc.), chronomodulated infusion, dose reduction, reintroduction of oxaliplatin and topical administration [hepatic arterial infusion chemotherapy (HAIC), pressurized intraperitoneal aerosol chemotherapy (PIPAC), and hyperthermic intraperitoneal chemotherapy (HIPEC)]. This article provides recent updates related to the potential mechanisms, therapeutic strategies in treatment of OIPN, and pharmacokinetics of several methods of oxaliplatin administration in clinical trials.

Sodium-Calcium Exchanger 2: A Pivotal Role in Oxaliplatin Induced Peripheral Neurotoxicity and Axonal Damage?

Oxaliplatin (OHP)-induced peripheral neurotoxicity (OIPN) is a frequent adverse event of colorectal cancer treatment. OIPN encompasses a chronic and an acute syndrome. The latter consists of transient axonal hyperexcitability, due to unbalance in Na+ voltage-operated channels (Na+VOC). This leads to sustained depolarisation which can activate the reverse mode of the Na+/Ca2+ exchanger 2 (NCX2), resulting in toxic Ca2+ accumulation and axonal damage (ADa). We explored the role of NCX2 in in vitro and in vivo settings. Embryonic rat Dorsal Root Ganglia (DRG) organotypic cultures treated with SEA0400 (SEA), a NCX inhibitor, were used to assess neuroprotection in a proof-of-concept and pilot study to exploit NCX modulation to prevent ADa. In vivo, OHP treated mice (7 mg/Kg, i.v., once a week for 8 weeks) were compared with a vehicle-treated group (n = 12 each). Neurophysiological and behavioural testing were performed to characterise acute and chronic OIPN, and morphological analyses were performed to detect ADa. Immunohistochemistry, immunofluorescence, and western blotting (WB) analyses were also performed to demonstrate changes in NCX2 immunoreactivity and protein expression. In vitro, NCX inhibition was matched by ADa mitigation. In the in vivo part, after verifyingboth acute and chronic OIPN had ensued, we confirmed via immunohistochemistry, immunofluorescence, and WB that a significant NCX2 alteration had ensued in the OHP group. Our data suggest NCX2 involvement in ADa development, paving the way to a new line of research to prevent OIPN.

Biomarkers of Chemotherapy-Induced Peripheral Neuropathy: Current Status and Future Directions

Chemotherapy induced peripheral neuropathy (CIPN) is an often severe and debilitating complication of multiple chemotherapeutic agents that can affect patients of all ages, across cancer diagnoses. CIPN can persist post-therapy, and significantly impact the health and quality of life of cancer survivors. Identifying patients at risk for CIPN is challenging due to the lack of standardized objective measures to assess for CIPN. Furthermore, there are no approved preventative treatments for CIPN, and therapeutic options for CIPN remain limited once it develops. Biomarkers of CIPN have been studied but are not widely used in clinical practice. They can serve as an important clinical tool to identify individuals at risk for CIPN and to better understand the pathogenesis and avenues for treatment of CIPN. Here we review promising biomarkers of CIPN in humans and their clinical implications.

New diagnostic measures of oxaliplatin-induced peripheral sensory neuropathy

OBJECTIVE

Oxaliplatin-induced peripheral neuropathy (OIPN) is an unwanted side effect of oxaliplatin chemotherapy treatment. OIPN manifests in an acute phase that lasts a few days after injection and a persistent phase that may become chronic. Currently, there is no consensus about a clinically applicable, quantitative, and objective measure of OIPN.

METHODS

Seventeen patients treated with oxaliplatin containing adjuvant chemotherapy for stage III colon cancer, but otherwise healthy, were tested with six quantitative sensory tests (QST) and five large fibre perception threshold tracking (PTT) measures (quantified by, e.g., rheobase and electrotonus threshold) one hour before each of the 12 chemotherapy cycles given at two weeks' intervals. These measures were repeated at 3, 6, and 12-month follow-ups. The temporal development of OIPN assessed by the Common Terminology Criteria for Adverse Events (CTCAE) scale, QST, and PTT measures was calculated by linear regression.

RESULTS

The CTCAE score showed a tri-phasic increase during the treatment and remained increased during the follow-up. The vibration threshold (R = 0.25, p<0.001), the cold pain threshold (R = 0.17, p = 0.02), and the rheobase (R = 0.28, p < 0.001) increased during treatment, whereas the cold detection threshold (R=-0.16, p = 0.002) decreased. The cold pain threshold and the rheobase remained increased, and the cold detection and heat pain threshold remained decreased during follow-up.

CONCLUSIONS

Increased cold pain sensitivity and decreased large fibre sensitivity (increased rheobase) correlate to the persistent OIPN, whereas the CTCAE score assesses both acute and persistent OIPN. Furthermore, the novel PTT method assessed the nerve excitability changes caused by the oxaliplatin.

Management of Side Effects in the Personalized Medicine Era: Chemotherapy-Induced Peripheral Neurotoxicity

Pharmacogenomics is a powerful tool to predict individual response to treatment, in order to personalize therapy, and it has been explored extensively in oncology practice. Not only efficacy on the malignant disease has been investigated but also the possibility to predict adverse effects due to drug administration. Chemotherapy-induced peripheral neurotoxicity (CIPN) is one of those. This potentially severe and long-lasting/permanent side effect of commonly administered anticancer drugs can severely impair quality of life (QoL) in a large cohort of long survival patients. So far, a pharmacogenomics-based approach in CIPN regard has been quite delusive, making a methodological improvement warranted in this field of interest: even the most refined genetic analysis cannot be effective if not applied correctly. Here we try to devise why it is so, suggesting how THE "bench-side" (pharmacogenomics) might benefit from and should cooperate with THE "bed-side" (clinimetrics), in order to make genetic profiling effective if applied to CIPN.

Platinum-Induced Peripheral Neuropathy (PIPN): ROS-Related Mechanism, Therapeutic Agents, and Nanosystems

Platinum (Pt) drugs (e.g., oxaliplatin, cisplatin) are applied in the clinic worldwide for the treatment of various cancers. However, platinum-induced peripheral neuropathy (PIPN) caused by the accumulation of Pt in the peripheral nervous system limits the clinical application, whose prevention and treatment are still a huge challenge. To date, Pt-induced reactive oxygen species (ROS) generation has been studied as one of the primary mechanisms of PIPN, whose downregulation would be feasible to relieve PIPN. This review will discuss ROS-related PIPN mechanisms including Pt accumulation in the dorsal root ganglia (DRG), ROS generation, and cellular regulation. Based on them, some antioxidant therapeutic drugs will be summarized in detail to alleviate the Pt-induced ROS overproduction. More importantly, we focus on the cutting-edge nanotechnology in view of ROS-related PIPN mechanisms and will discuss the rational fabrication of tailor-made nanosystems for efficiently preventing and treating PIPN. Last, the future prospects and potential breakthroughs of these anti-ROS agents and nanosystems will be briefly discussed.

Neuromuscular complications of cancer therapy

PURPOSE OF THE REVIEW

The neuromuscular complications of cancer therapy include chemotherapy-induced peripheral neurotoxicity (CIPN), immune-related neuromuscular complications to immune checkpoint inhibitors and radiation-induced neuropathy/plexopathy. With a wider focus on CIPN, we will discuss new pathogenetic insights, recent predictive biomarkers and emerging therapies for neuromuscular complications of cancer therapy.

RECENT FINDINGS

Findings from recent preclinical studies have improved our knowledge on new CIPN pathogenetic pathways, including the activation of senescence-like processes in neurons, axonal degeneration and neuroinflammation. Metabolomics and serum neurofilament light chain levels appear the most promising biomarkers to predict CIPN development and severity. There is some recent evidence of promising pharmacological compounds to prevent or treat CIPN, and new drugs are in early development and testing.

SUMMARY

A multimodal assessment, with neurophysiological, imaging and patient-reported outcome measures, coupled with the use of reliable blood or genetic biomarkers, may offer pathogenetic grounds for future preventive and symptomatic strategies for the multidisciplinary treatment of neuromuscular complications of cancer therapy.

Efficacy of Exercise Rehabilitation Program in Relieving Oxaliplatin Induced Peripheral Neurotoxicity

BACKGROUND

Peripheral neurotoxicity is common in patients with digestive malignancies receiving chemotherapy containing oxaliplatin, and there is still no effective drug to prevent or treat this complication.

METHODS

Seventy-nine patients receiving chemotherapy containing oxaliplatin were included, and the relationship between chemotherapy regimens, cycles, and cumulative dose of oxaliplatin and peripheral neurotoxicity was analyzed. Patients were divided into two groups of control or intervention. Twenty-eight patients in the control group received routine chemotherapy care, and 51 patients in the intervention group underwent two-week exercise rehabilitation program. Patients' Functional Assessment of Cancer Therapy/Gynecologic Oncology Group - Neurotoxicity (FACT/GOG-Ntx), functional tests, and Brief Pain Inventory(BPI) scores as well as interference life scores were assessed before intervention and two weeks after the intervention.

RESULTS

In the intervention group, 52.9% patients previously exercised regularly. The FOLFOX regimen was more common in peripheral neurotoxicity (73.4%), and the median oxaliplatin cycles for neurotoxicity was 9 (ranging from 1 to 16). The mean cumulative dose of oxaliplatin was 1080.02 ± 185.22 mg, both the cycles and cumulative dose were positively correlated with the occurrence of peripheral neurotoxicity. Compared with control, the scores of FACT/GOG-Ntx, functional tests, and BPI were significantly decreased in the intervention group (p < 0.05).

CONCLUSION

Chemotherapy cycles and cumulative doses were in relation with OIN  , and exercise rehabilitation program could effectively alleviate OIN.<br />.

Real world, open label experience with lacosamide against acute painful oxaliplatin-induced peripheral neurotoxicity

We report the outcome of a pilot, open-label study that tested the potential of lacosamide (200 mg/bi.d) as an effective and safe symptomatic treatment against acute painful oxaliplatin-induced peripheral neurotoxicity (OXAIPN). Lacosamide was introduced in 18 colorectal cancer patients with evidence of clinically significant acute, painful OXAIPN after infusion of the third course (T1) of oxaliplatin-based chemotherapy (FOLFOX4) and was maintained until completion of all 12 courses (T4). The OXA-Neuropathy Questionnaire (OXA-NQ) was used to record the severity of acute OXAIPN; the PI-NRS estimated the severity of neuropathic pain, while the chronic OXAIPN was graded with TNSc. The EuroQOL (EQ-5D) instrument was also applied. The Patient Global Impression of Change (PGIC) scale measured the lacosamide-attributed perception of change. LCM-responders were considered those with ≥50% reduction in PI-NRS and OXA-NQ scores at T4, compared to T1. Patients experienced on T1 a median number of acute OXAIPN symptoms of 4 and had a median neuropathic pain severity score of 6, which was strongly related to lower quality of life, according to EQ-VAS (P < .001). At T4, 12 patients (66.7%) were classified as responders. A significant clinical improvement was documented in the severity of acute OXAIPN and neuropathic pain in relation to lacosamide (P < .001) at T4 compared to T1, which was associated with improved EQ-VAS scores (P < .001). Twelve patients scored PGIC ≥5 (lacosamide-attributed) at T4. There were no incidences of early drop-outs for safety reasons. Lacosamide appears to be an effective and well-tolerated symptomatic treatment against acute, painful OXAIPN.