Oxaliplatin Neurotoxicity

A transient inflammatory response contributes to oxaliplatin neurotoxicity in mice

OBJECTIVES

Peripheral neuropathy is a relevant dose-limiting adverse event that can affect up to 90% of oncologic patients with colorectal cancer receiving oxaliplatin treatment. The severity of neurotoxicity often leads to dose reduction or even premature cessation of chemotherapy. Unfortunately, the limited knowledge about the molecular mechanisms related to oxaliplatin neurotoxicity leads to a lack of effective treatments to prevent the development of this clinical condition. In this context, the present work aimed to determine the exact molecular mechanisms involved in the development of oxaliplatin neurotoxicity in a murine model to try to find new therapeutical targets.

METHODS

By single-cell RNA sequencing (scRNA-seq), we studied the transcriptomic profile of sensory neurons and satellite glial cells (SGC) of the Dorsal Root Ganglia (DRG) from a well-characterized mouse model of oxaliplatin neurotoxicity.

RESULTS

Analysis of scRNA-seq data pointed to modulation of inflammatory processes in response to oxaliplatin treatment. In this line, we observed increased levels of NF-kB p65 protein, pro-inflammatory cytokines, and immune cell infiltration in DRGs and peripheral nerves of oxaliplatin-treated mice, which was accompanied by mechanical allodynia and decrease in sensory nerve amplitudes.

INTERPRETATION

Our data show that, in addition to the well-described DNA damage, oxaliplatin neurotoxicity is related to an exacerbated pro-inflammatory response in DRG and peripheral nerves, and open new insights in the development of anti-inflammatory strategies as a treatment for preventing peripheral neuropathy induced by oxaliplatin.

The Combination of Zinc and Melatonin Enhanced Neuroprotection and Attenuated Neuropathy in Oxaliplatin-Induced Neurotoxicity

Objective

The present study was designed to investigate the possible synergistic effects of melatonin with zinc in the prevention and treatment of oxaliplatin-induced neurotoxicity in rats.

Methodology

Forty-eight male Wistar albino rats were used and randomly allocated into six groups: The negative control group, oxaliplatin group, zinc + oxaliplatin group, melatonin + oxaliplatin group, zinc + melatonin + oxaliplatin prevention-approach group, and zinc + melatonin + oxaliplatin treatment-approach group. The thermal nociceptive/hyperalgesia tests were performed. Brain tissue homogenate was used for measuring GFAP, NCAM, TNF α, MAPK 14, NF-kB, GPX, and SOD. Brain tissue was sent for histopathological and immunohistochemistry studies.

Results

The combination therapies showed improvement in the behavioral tests. A significant increase in GPX and SOD with a significant decrease in GFAP levels resulted in the prevention approach. TNF α decreased significantly in the treatment approach. No significant changes were seen in NCAM, NFkB, and MAPK-14. The histopathological findings support the biochemical results. Additionally, immunohistochemistry revealed a significant attenuation of p53 and a non-significant decrease in Bcl2 levels in the combination groups.

Conclusion

The combination of zinc with melatonin for the prevention approach was effective in attenuating neurotoxicity induced by oxaliplatin. The proposed mechanisms are boosting the antioxidant system and attenuating the expression of p53, GFAP, and TNF-α.

Physical Activity: A Systematic Review to Inform Nurse Recommendations During Treatment for Colorectal Cancer

Colorectal cancer (CRC) is the third most common cancer in the world (American Cancer Society [ACS], 2021). Because of increasing survival rates, there is a need improve survivors' quality of life (QOL), physical functioning, recurrence risk, and comorbidity prevalence (ACS, 2020). Many patients with CRC have poor QOL during and after treatment; other common side effects include fatigue, depression, anxiety, and decreased sleep quality (Bourke et al., 2014; Cramer et al., 2014; Gao et al., 2020). Focusing on the treatment period is important because physical activity (PA) may decrease side effects and prevent PA decline and functional decline, both of which can become significant barriers to PA following treatment. In addition, patients with CRC have a higher rate of comorbidities than patients without cancer, making lifestyle changes pre- and post-treatment particularly important for their continued survival and QOL (ACS, 2020).

Predictive Biomarkers of Oxaliplatin-Induced Peripheral Neurotoxicity

Oxaliplatin (OXA) is a platinum compound primarily used in the treatment of gastrointestinal cancer. OXA-induced peripheral neurotoxicity (OXAIPN) is the major non-hematological dose-limiting toxicity of OXA-based chemotherapy and includes acute transient neurotoxic effects that appear soon after OXA infusion, and chronic non-length dependent sensory neuronopathy symmetrically affecting both upper and lower limbs in a stocking-and-glove distribution. No effective strategy has been established to reverse or treat OXAIPN. Thus, it is necessary to early predict the occurrence of OXAIPN during treatment and possibly modify the OXA-based regimen in patients at high risk as an early diagnosis and intervention may slow down neuropathy progression. However, identifying which patients are more likely to develop OXAIPN is clinically challenging. Several objective and measurable early biomarkers for OXAIPN prediction have been described in recent years, becoming useful for informing clinical decisions about treatment. The purpose of this review is to critically review data on currently available or promising predictors of OXAIPN. Neurological monitoring, according to predictive factors for increased risk of OXAIPN, would allow clinicians to personalize treatment, by monitoring at-risk patients more closely and guide clinicians towards better counseling of patients about neurotoxicity effects of OXA.

Duloxetine against symptomatic chemotherapy-induced peripheral neurotoxicity in cancer survivors: a real world, open-label experience

The objective of this observational study was to evaluate the efficacy and safety of duloxetine in a cohort of 100 cancer survivors with chemotherapy-induced peripheral neurotoxicity (CIPN). CIPN was graded employing the TNSc and the NCI-CTCv4. The Patient Global Impression of Change (PGIC) scale measured the efficacy of duloxetine (1: no benefit; to 7: excellent response). A clinically meaningful response was considered a PGIC > 4. Median age was 62 (29-81) years and 42% were male. CIPN was graded as grades 1, 2 and 3 in 20, 66, and 14% of patients, respectively. Median time to duloxetine initiation was 6 (1-63) months after chemotherapy. Fifty-seven patients early dropped out from duloxetine, due to lack of efficacy (20%) or side effects (37%). Male patients more frequently discontinued duloxetine due to lack of efficacy (35.7 vs. 8.6% P = 0.001). PGIC scores were higher in female patients (4 vs. 1, P = 0.001), taxane-treated patients (4 vs. 1, P = 0.042) and with short-lasting (<6 months) CIPN (4 vs. 1, P = 0.008). Patients with long-lasting CIPN had a higher rate of adverse events (47 vs. 27%, P = 0.038) and discontinuation (54.8 vs. 45.1%, P = 0.023). In the multivariate analysis, female gender and short-lasting CIPN were independently associated with a favorable response to duloxetine. Low tolerability, male gender, and long-lasting CIPN significantly limited duloxetine use in daily practice setting. A minority of cancer survivors with CIPN treated with duloxetine had a meaningful CIPN improvement, and tolerability was overall low. Female gender and short-term CIPN were independently associated with a favorable response to duloxetine.

Pathogenesis of platinum-induced peripheral neurotoxicity: Insights from preclinical studies

One of the most relevant dose-limiting adverse effects of platinum drugs is the development of a sensory peripheral neuropathy that highly impairs the patients' quality of life. Nowadays there are no available efficacy strategies for the treatment of platinum-induced peripheral neurotoxicity (PIPN), and the only way to prevent its development and progression is by reducing the dose of the cytostatic drug or even withdrawing the chemotherapy regimen. This clinical issue has been the main focus of hundreds of preclinical research works during recent decades. As a consequence, dozens of in vitro and in vivo models of PIPN have been developed to elucidate the molecular mechanisms involved in its development and to find neuroprotective targets. The apoptosis of peripheral neurons has been identified as the main mechanism involved in PIPN pathogenesis. This mechanism of DRG sensory neurons cell death is triggered by the nuclear and mitochondrial DNA platination together with the increase of the oxidative cellular status induced by the depletion of cytoplasmic antioxidant mechanisms. However, since there has been no successful transfer of preclinical results to clinical practise in terms of therapeutic approaches, some mechanisms of PIPN pathogenesis still remain to be elucidated. This review is focused on the pathogenic mechanisms underlying PIPN described up to now, provided by the critical analysis of in vitro and in vivo models.

Assembly simulation and synergistic chemotherapy of TPGS derivative functionalized polymersomes in hepatocellular carcinoma

Aim: Multidrug resistance and severe side effects lead to poor therapeutic efficacy of monotherapy against hepatocellular carcinoma. Here, a targeting codelivery nanocomposite system is constructed to reverse tumor multidrug resistance and realize a combination therapy of doxorubicin and oxaliplatin. Methods & materials: We simulate the composited structure of TPGS-lactobionic acid conjugate (TLA) modified methyl poly(ethylene glycol)-polylactide (mPP) polymersomes using dissipative particle dynamics. Cellular uptake and drug retention, cytotoxicity, in vivo antitumor efficacy and toxicity were evaluated. Results: TLA/mPP composited polymersomes improved intracellular accumulation of coloaded drugs via active targeting ability and P-gp efflux inhibition, leading to strong cytotoxicity against HepG2/ADR cells and potent tumor inhibition (93.5%) for HepG2/ADR tumor. Conclusion: TLA/mPP composited polymersomes represent a promising multifunctional nanoplatform against hepatocellular carcinoma.

Rechallenge with oxaliplatin and peripheral neuropathy in colorectal cancer patients

BACKGROUND

Oxaliplatin (OXA) is a cornerstone in the treatment of colorectal cancer (CRC). Retreatment with OXA is frequently considered as salvage treatment. OXA-induced neuropathy (OIN) is the most frequent and feared long-term side effect.

PATIENTS AND METHODS

CRC patients receiving at least twice OXA-based chemotherapy lines at our institution between June 2000 and July 2016 were reviewed. The aim of this study was to investigate whether retreatment with OXA increases the risk of developing new or worsening previous neuropathy. OIN was assessed by National Cancer Institute-Common Toxicity Criteria for Adverse Events (NCI), Total Neuropathy Score© (TNS) and nerve-conduction studies.

RESULTS

106 patients were included in the analysis. Median age at OXA-based retreatment was 61.5 (20-83) years. After the first OXA-based chemotherapy treatment, 63.4% of patients developed OIN, 30.7 and 8.9% grades 2 and 3, respectively, after a median of 11 (1-17) cycles. After 30 (11-90) months of median to retreatment with a median of 8 (1-14) OXA cycles, 39.6, 22.6, and 0% of patients developed grade 1, 2, and 3 OIN, respectively. Worsening of the previous OIN was observed in one-third (31.1%) of all patients. OXA-cumulative dose was independently associated with greater risk of worsening OIN (p < 0.001). Non-significant trend towards higher TNSc© scores after retreatment was observed [5 (0-11) vs 6 (3-13), p = 0.083].

CONCLUSION

Retreatment with OXA in CRC patients is a feasible option even in patients who previously developed moderate or severe OIN. One-third of patients' OIN was worsened by retreatment. Neurological monitoring should be considered.

Serum micronutrients and prealbumin during development and recovery of chemotherapy-induced peripheral neuropathy

Chemotherapy-induced peripheral neuropathy (CIPN) is a frequent adverse event. Nutritional status can become impaired in cancer patients, potentially contributing to neuropathy's evolution. Our aim was to evaluate serum micronutrients and prealbumin in a cohort of 113 solid-cancer patients receiving platinum and taxane compounds during the development and recovery of neuropathy, up to 1 year after finishing treatment. CIPN was graded according to Total Neuropathy Score(©) and NCI.CTCv3 at T0 (baseline), T1 (1-3 months), and T12 (12 months) after chemotherapy. CIPN was classified as asymptomatic (< grade 2) or symptomatic (≥2). CIPN recovery was defined as ≥1 grade improvement at T12. Symptomatic CIPN developed in 52% of patients. Symptomatic patients presented a higher increase in TNSc (p < 0.001), in TNSr(©) (p < 0.001), and decrease in sural (p < 0.001) and radial nerve conduction (p < 0.001). No significant differences with any of the micronutrients were observed along T0-T1 period between severity or chemotherapy groups. By T12, symptomatic patients without recovery had a decrease in vitamin E levels (p = 0.019) and prealbumin (p = 0.062) compared with those symptomatic that improved. A correlation between the variation of vitamin E and prealbumin at T0-T1 (r = 0.626, p = 0.001) and T1-T12 (r = 0.411, p = 0.06) was observed. After chemotherapy treatment, the improvement of patients displaying symptomatic neuropathy is related to vitamin E and prealbumin serum levels. Our results suggest that nutritional status can play a role in CIPN recovery.

Efficacy of a Novel Sigma-1 Receptor Antagonist for Oxaliplatin-Induced Neuropathy: A Randomized, Double-Blind, Placebo-Controlled Phase IIa Clinical Trial

This trial assessed the efficacy of MR309 (a novel selective sigma-1 receptor ligand previously developed as E-52862) in ameliorating oxaliplatin-induced peripheral neuropathy (oxaipn). A discontinuous regimen of MR309 (400 mg/day, 5 days per cycle) was tested in patients with colorectal cancer receiving FOLFOX in a phase II, randomized, double-blind, placebo-controlled, multicenter clinical trial. Outcome measures included changes in 24-week quantitative measures of thermal sensitivity and total neuropathy score. In total, 124 patients were randomized (1:1) to MR309 or placebo. Sixty-three (50.8%) patients withdrew prematurely before completing 12 planned oxaliplatin cycles. Premature withdrawal because of cancer progression was less frequent in the MR309 group (7.4% vs 25.0% with placebo; p = 0.054). MR309 significantly reduced cold pain threshold temperature [mean treatment effect difference (SE) vs placebo: 5.29 (1.60)°C; p = 0.001] and suprathreshold cold stimulus-evoked pain intensity [mean treatment effect difference: 1.24 (0.57) points; p = 0.032]. Total neuropathy score, health-related quality-of-life measures, and nerve-conduction parameters changed similarly in both arms, whereas the proportion of patients with severe chronic neuropathy (National Cancer Institute Common Terminology Criteria for Adverse Events ≥ 3) was significantly lower in the MR309 group (3.0% vs 18.2% with placebo; p = 0.046). The total amount of oxaliplatin delivered was greater in the active arm (1618.9 mg vs 1453.8 mg with placebo; p = 0.049). Overall, 19.0% of patients experienced at least 1 treatment-related adverse event (25.8% and 11.9% with MR309 and placebo, respectively). Intermittent treatment with MR309 was associated with reduced acute oxaipn and higher oxaliplatin exposure, and showed a potential neuroprotective role for chronic cumulative oxaipn. Furthermore, MR309 showed an acceptable safety profile.

Bevacizumab maintenance treatment for colorectal cancer: A meta-analysis

AIM

to perform a meta-analysis to evaluate the efficacy and safety of bevacizumab in the maintenance treatment of colorectal cancer.

METHODS

Literature retrieval was conducted by searching Cochrane Controlled Trials Register (CCTR), MEDLINE (1994-August 2016), Chinese Biomedical database (1978-August 2016) and CNKI (1994-August 2016). The quality of included articles was assessed based on the approach commended by the International Cochrane Collaboration. Statistical analysis was performed using RevMan5.0 software.

RESULTS

Eight randomized controlled clinical trials were included, but concealed allocation was not mentioned in all of them. Although loss to follow-up was reported and intention-to-treat analysis was conducted in all the included articles, blinding method was covered only in one paper. Compared with chemotherapy alone, chemotherapy combined with bevacizumab was associated with prolonged progression free survival (PFS; HR = 0.76, 95%CI: 0.64-0.90) and median overall survival (OS; HR = 0.82, 95%CI: 0.74-0.89). After six cycles of XELOX (capecitabine, oxaliplatin, and fluorouracil) + bevacizumab, the patients received maintenance therapy comprising either XELOX + bevacizumab or capecitabine + bevacizumab (PFS: HR = 1.68, 95%CI: 1.21-2.35; OS: HR = 1.38, 95%CI: 0.91-2.08). In patients who had disease progression after first-line chemotherapy combined with bevacizumab, bevacizumab combined with second-line maintenance chemotherapy provided survival advantage (PFS: HR = 0.76, 95%CI: 0.69-0.83; OS: HR = 0.83, 95%CI: 0.72-0.95). chemotherapy plus bevacizumab increased the incidence of grade 3-4 toxicities (RR = 1.19, 95%CI: 1.11-1.28).

CONCLUSION

Bevacizumab combined with chemotherapy can improve the PFS and OS in the treatment of metastatic colorectal cancer, but increases the incidence of grade 3-4 toxicities.