Characteristics and risk factors of bortezomib induced peripheral neuropathy: A systematic review of phase III trials

Bortezomib for rituximab-refractory immune-mediated thrombotic thrombocytopenic purpura in the caplacizumab era: an Italian multicenter study

BACKGROUND

Immune-mediated thrombotic thrombocytopenic purpura (iTTP) patients are not responsive to standard rituximab in approximately 10% to 15% of cases, and oral immunosuppressants showed controversial results with significant toxicity. Targeting plasma cells with bortezomib appears promising, but the available evidence is scarce and stems only from isolated reports in the precaplacizumab era.

OBJECTIVES

To evaluate the safety and efficacy of bortezomib in rituximab-refractory iTTP patients.

METHODS

We conducted a retrospective observational multicenter study among 13 Italian iTTP treating centers, collecting data from May 2017 to May 2023 (caplacizumab was licensed in Italy in January 2020).

RESULTS

Bortezomib was effective in 10/17 patients (59%). Eleven were treated in the acute phase (9/11 responders, 82%, allowing discontinuation of caplacizumab in 5/6 treated patients), and 7 during clinical remission (2/7 responders, 28%). Responses occurred at a median time of 30 days, but 3 patients responded after 4 months. The median duration of response was 22 months (IQR, 10-38), still ongoing in 6 patients at the time of data cutoff. Responders had fewer previous acute iTTP episodes than nonresponders (median [IQR], 1 [1,2] vs 5.5 [2-7]; P = .03). Eight subjects (47%) reported toxicities, mostly in those treated with ≥2 cycles.

CONCLUSION

Durable responses to bortezomib were registered in about 60% of multirefractory iTTP patients with mild to moderate toxicities. The occurrence of late responses (ie, after 30 days) suggests a "watchful waiting" approach after bortezomib treatment.

Bortezomib-induced neuropathy in multiple myeloma manifesting as foot drop due to peroneal nerve palsy

We present the case of a man in his 50s with multiple myeloma who developed foot drop after receiving bortezomib-dexamethasone combination chemotherapy. Diagnostic evaluations, including haematological parameters, nerve conduction studies and imaging, were performed to confirm the diagnosis and assess the extent of neuropathy. He was managed conservatively with analgesics and vitamin supplements, and bortezomib was temporarily withheld. The neuropathy gradually improved, and bortezomib was successfully reintroduced without recurrence of foot drop. Bortezomib-induced foot drop is a rare complication of bortezomib-based therapy in patients with multiple myeloma. Early recognition and intervention are crucial to minimise impact on quality of life. This case report emphasises the safe reintroduction of bortezomib post-neuropathy resolution, emphasising the importance of early recognition and multidisciplinary management.

Genetic Risk Factors for Bortezomib-induced Neuropathic Pain in an Asian Population: A Genome-wide Association Study in South Korea

Bortezomib-induced neuropathic pain (BINP) poses a challenge in multiple myeloma (MM) treatment. Genetic factors play a key role in BINP susceptibility, but research has predominantly focused on Caucasian populations. This research explored novel genetic risk loci and pathways associated with BINP development in Korean MM patients while evaluating the reproducibility of variants from Caucasians. Clinical data and buffy coat samples from 185 MM patients on bortezomib were collected. The cohort was split into discovery and validation cohorts through random stratification of clinical risk factors for BINP. Genome-wide association study was performed on the discovery cohort (n = 74) with Infinium Global Screening Array-24 v3.0 BeadChip (654,027 single nucleotide polymorphism [SNPs]). Relevant biological pathways were identified using the pathway scoring algorithm. The top 20 SNPs were validated in the validation cohort (n = 111). Previously reported SNPs were validated in the entire cohort (n = 185). Pathway analysis of the genome-wide association study results identified 31 relevant pathways, including immune systems and endosomal vacuolar pathways. Among the top 20 SNPs from the discovery cohort, 16 were replicated, which included intronic variants in ASIC2 and SMOC2, recently implicated in nociception, as well as intergenic variants or long noncoding RNAs. None of the 17 previously reported SNPs remained significant in our cohort (rs2274578, P = .085). This study represents the first investigation of novel genetic loci and biological pathways associated with BINP occurrence. Our findings, in conjunction with existing Caucasian studies, expand the understanding of personalized risk prediction and disease mechanisms. PERSPECTIVE: This article is the first to explore novel genetic loci and pathways linked to BINP in Korean MM patients, offering novel insights beyond the existing research focused on Caucasian populations into personalized risk assessment and therapeutic strategies of BINP.

Reporting of adverse events of treatment interventions in multiple myeloma: an overview of systematic reviews

The present study is an overview of systematic reviews focusing on adverse events of antimyeloma treatments. It provides a systematic description of adverse events as they are reported in the systematic reviews as well as a critical appraisal of included reviews. We conducted a comprehensive literature search in the most widely used electronic databases looking for systematic reviews that had an adverse event of an antimyeloma treatment intervention as primary outcome. Two independent reviewers conducted selection of included studies and data extraction on predesigned online forms and assessed study quality using AMSTAR 2. Overall corrected covered area (CCA) was calculated to examine the overlap of primary studies across systematic reviews. After screening eligible studies, 23 systematic reviews were included in this overview. Seven reviews with overall CCA of 14.7% examined cardiovascular adverse events of different drugs, including immunomodulatory drugs and proteasome inhibitors (mainly carfilzomib). Nine focused on infections, presenting with overall CCA of 5.8%, each one focused on a different drug or drug class. Three studied thromboembolism in patients treated either with lenalidomide, any immunomodulatory drug, or with daratumumab and had an overall CCA equal to 1.5%. Four more reviews focused on bortezomib-associated neurotoxicity, carfilzomib-associated renal toxicity, or second primary malignancies as an adverse event of lenalidomide or anti-CD38 monoclonal antibody treatment. The quality of included studies as judged by AMSTAR 2 was mostly critically low. Absence of a priori registered protocol and formal assessment of risk of bias of included primary studies were the most common shortcomings. Reporting of antimyeloma drug-associated toxicity is supported by multiple systematic reviews; nevertheless, methodological quality of existing reviews is mostly low.

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.

Bortezomib-induced peripheral neuropathy: Clinical features, molecular basis, and therapeutic approach

Bortezomib is the first-line standard and most effective chemotherapeutic for multiple myeloma; however, bortezomib-induced peripheral neuropathy (BIPN) severely affects the chemotherapy regimen and has long-term impact on patients under maintenance therapy. The pathogenesis of BIPN is poorly understood, and basic research and development of BIPN management drugs are in early stages. Besides chemotherapy dose reduction and regimen modification, no recommended prevention and treatment approaches are available for BIPN apart from the International Myeloma Working Group guidelines for peripheral neuropathy in myeloma. An in-depth exploration of the pathogenesis of BIPN, development of additional therapeutic approaches, and identification of risk factors are needed. Optimizing effective and standardized BIPN treatment plans and providing more decision-making evidence for clinical diagnosis and treatment of BIPN are necessary. This article reviews the recent advances in BIPN research; provides an overview of clinical features, underlying molecular mechanisms, and therapeutic approaches; and highlights areas for future studies.

Health-Related Complications during Follow-Up and Their Impact on Blood Cancer Survivors: Results from the "Aftercare in Blood Cancer Survivors" (ABC) Study

INTRODUCTION

Blood cancer survivors are at increased risk for medical complications.

METHODS

Our questionnaire-based study involved 1,551 blood cancer survivors with a ≥3-year interval since the last intense treatment. Its goal was to quantify health-related complications during follow-up and assess their impact on the patients' lives.

RESULTS

A total of 20.4% of the responding survivors reported a disease relapse, most often in indolent lymphomas. Second primary malignancies occurred in 14.1%, primarily in lymphoma and allogeneic transplantation survivors. The most frequent malignancy was basal cell carcinoma of the skin, but myeloid malignancies, melanoma, bladder, head-and-neck, and thyroid cancer also appeared disproportionately frequent. An increased infection rate was reported by 43.7%, most often after allogeneic transplantation. New cardiovascular diseases were reported by 30.2%, with a high rate of thromboembolic events in multiple myeloma (MM) and myeloproliferative diseases. Polyneuropathies were reported by 39.1%, most often by survivors with a history of MM or aggressive lymphoma. Disease relapse was perceived as the highest burden, followed by second primary malignancy, increased infection frequency, and polyneuropathy. In each area investigated, the range of perceived severities was wide.

CONCLUSIONS

Health-related complications are frequent during blood cancer follow-up, with significant repercussions on the patients' lives.

Chemotherapy-Induced Peripheral Neuropathy Impacts Quality of Life and Activities of Daily Living of Brazilian Multiple Myeloma Patients

BACKGROUND

Survival in multiple myeloma (MM) has improved in the past years with the introduction of immunomodulators and proteasome inhibitors. However, chemotherapyinduced peripheral neuropathy (CIPN) is associated with both drug classes affecting Health- Related Quality of Life (HRQoL) and activities of daily living (ADL).

OBJECTIVE

We evaluated CIPN in MM patients to identify associated factors and impacts on HRQoL and ADL.

METHODS

This is a cross-sectional study with Brazilian patients from public and private health services. Patients were interviewed using validated tools to measure CIPN and HRQoL, along with sociodemographic and clinical questions. Logistic regression was used to assess the association of CIPN with sociodemographic, clinical, and HRQoL variables.

RESULTS

In total, 217 patients were eligible for the study. The median age was 67, 50.9% were women, 51.6% had low income, 47.5% had low education, and 55.3% attended private health services. The chemotherapy regimen most used was the combination of cyclophosphamide, thalidomide, and dexamethasone (17.5%) among the 24 types of regimens found. Most patients (90.3%) had at least one CIPN symptom: 62.7% were severe, and 51.62% were extremely bothered ADL. Numbness was the most common symptom (40.6%). CIPN was independently associated with education, hospitalization, chemotherapy, side effects, disease symptoms, and global health status in HRQoL.

CONCLUSION

MM patients showed a high frequency of CIPN, which affected ADL and impaired HRQoL. Early and accurate detection of CIPN and dose management in patients with thalidomide and bortezomib-based regimens should be performed to provide better treatment outcomes and avoid permanent disabilities.

Bortezomib Is Toxic but Induces Neurogenesis and Inhibits TUBB3 Degradation in Rat Neural Stem Cells

Bortezomib (BTZ) is a proteasome inhibitor used to treat multiple myeloma (MM). However, the induction of peripheral neuropathy is one of the major concerns in using BTZ to treat MM. In the current study, we have explored the effects of BTZ (0.01-5 nM) on rat neural stem cells (NSCs). BTZ (5 nM) induced cell death; however, the percentage of neurons was increased in the presence of mitogens. BTZ reduced the B-cell lymphoma 2 (Bcl-2)/Bcl-2 associated X protein ratio in proliferating NSCs and differentiated cells. Inhibition of βIII-tubulin (TUBB3) degradation was observed, but not inhibition of glial fibrillary acidic protein degradation, and a potential PEST sequence was solely found in TUBB3. In the presence of growth factors, BTZ increased cAMP response element-binding protein (CREB) phosphorylation, brain-derived neurotrophic factor (Bdnf) transcription, BDNF expression, and Tubb3 transcription in NSCs. However, in the neuroblastoma cell line, SH-SY5Y, BTZ (1-20 nM) only increased cell death without increasing CREB phosphorylation, Bdnf transcription, or TUBB3 induction. These results suggest that although BTZ induces cell death, it activates neurogenic signals and induces neurogenesis in NSCs.

Recent advances in the treatment and prevention of peripheral neuropathy after multiple myeloma treatment

The incidence of multiple myeloma (MM) is increasing year by year, requiring chemotherapy drugs to control the condition. With the advent of new proteasome inhibitors, immunomodulators, and monoclonal antibodies, the prognosis of patients has improved significantly. However, peripheral neuropathy caused by drugs limits the dose and duration of treatment, which seriously affects patients' quality of life and treatment outcome. Although the neuropathies induced by chemotherapy drugs have attracted much attention, their mechanism and effective prevention and treatment measures are not clear. Therefore, how to alleviate peripheral neuropathy caused by drugs for treatment of MM is a key issue in improving patients' quality of life and prolonging their survival time, which have some clinical value. In this paper, we review the current research on the pathogenesis, pharmacological and nonpharmacological treatment, and prevention, which expects to present instruction for peripheral neuropathy after treatment of MM.

Targeting KRAS in Colorectal Cancer: A Bench to Bedside Review

Colorectal cancer (CRC) is a heterogeneous disease with a myriad of alterations at the cellular and molecular levels. Kristen rat sarcoma (KRAS) mutations occur in up to 40% of CRCs and serve as both a prognostic and predictive biomarker. Oncogenic mutations in the KRAS protein affect cellular proliferation and survival, leading to tumorigenesis through RAS/MAPK pathways. Until recently, only indirect targeting of the pathway had been investigated. There are now several KRAS allele-specific inhibitors in late-phase clinical trials, and many newer agents and targeting strategies undergoing preclinical and early-phase clinical testing. The adequate treatment of KRAS-mutated CRC will inevitably involve combination therapies due to the existence of robust adaptive resistance mechanisms in these tumors. In this article, we review the most recent understanding and findings related to targeting KRAS mutations in CRC, mechanisms of resistance to KRAS inhibitors, as well as evolving treatment strategies for KRAS-mutated CRC patients.

CYP3A genetic variation and taxane-induced peripheral neuropathy: a systematic review, meta-analysis, and candidate gene study

Background: Taxane-induced peripheral neuropathy (TIPN) is an important cause of premature treatment cessation and dose-limitation in cancer therapy. It also reduces quality of life and survivorship in affected patients. Genetic polymorphisms in the CYP3A family have been investigated but the findings have been inconsistent and contradictory. Methods: A systematic review identified 12 pharmacogenetic studies investigating genetic variation in CYP3A4*22 and CYP3A5*3 and TIPN. In our candidate gene study, 288 eligible participants (211 taxane participants receiving docetaxel or paclitaxel, and 77 control participants receiving oxaliplatin) were successfully genotyped for CYP3A4*22 and CYP3A5*3. Genotyping data was transformed into a combined CYP3A metaboliser phenotype: Poor metabolisers, intermediate metabolisers and extensive metabolisers. Individual genotypes and combined CYP3A metaboliser phenotypes were assessed in relation to neurotoxicity, including by meta-analysis where possible. Results: In the systematic review, no significant association was found between CYP3A5*3 and TIPN in seven studies, with one study reporting a protective association. For CYP3A4*22, one study has reported an association with TIPN, while four other studies failed to show an association. Evaluation of our patient cohort showed that paclitaxel was found to be more neurotoxic than docetaxel (p < 0.001). Diabetes was also significantly associated with the development of TIPN. The candidate gene analysis showed no significant association between either SNP (CYP3A5*3 and CYP3A4*22) and the development of TIPN overall, or severe TIPN. Meta-analysis showed no association between these two variants and TIPN. Transformed into combined CYP3A metaboliser phenotypes, 30 taxane recipients were poor metabolisers, 159 were intermediate metabolisers, and 22 were extensive metabolisers. No significant association was observed between metaboliser status and case-control status. Summary: We have shown that the risk of peripheral neuropathy during taxane chemotherapy is greater in patients who have diabetes. CYP3A genotype or phenotype was not identified as a risk factor in either the candidate gene analysis or the systematic review/meta-analysis, although we cannot exclude the possibility of a minor contribution, which would require a larger sample size.

The nonlinear association between red blood cell distribution width (RDW) and bortezomib-related peripheral neurotoxicity (PN): A retrospective cohort study

Background

Previous evidence on the association of red blood cell distribution width (RDW) with bortezomib-induced peripheral neuropathy (BIPN) is limited. As a result, in this single-center retrospective cohort analysis, the link between RDW and BIPN was investigated.

Methods

This study4 comprised 376 patients with primary multiple myeloma (MM) who attended the Department of Haematology at Guizhou Provincial People's Hospital between 2013 and 2021. RDW and the occurrence of BIPN were the exposure and outcome variables, respectively. Demographic characteristics, pharmacological agents, co-morbidities, and MM-related indicators were all included as covariates. To investigate the relationship between RDW and BIPN, binary logistic regression and two-piecewise linear regression were utilized.

Results

The relationship between RDW and BIPN was found to be non-linear. RDW was not significantly associated with the risk of BIPN (odds ratio (OR): 0.99; 95% confidence interval (CI): 0.95 to 1.02; p-value: 0.4810) to the left of the inflection point (RDW = 72.3); to the right of the inflection point, each 1 ft increase in RDW was associated with an 7% increase in the risk of BIPN (OR: 1.07; 95% CI: 1.01 to 1.15; p-value: 0.046).

Conclusion

The relationship between RDW and the risk of BIPN demonstrated a threshold effect, with RDW exceeding 72.3 fl, indicating a relatively significant risk of BIPN.

An efficient cellular image-based platform for high-content screening of neuroprotective agents against chemotherapy-induced neuropathy

Chemotherapy-induced peripheral neuropathy (CIPN) is a major dose-limiting side effect, with no approved therapy for prevention or treatment. Here, we aimed to establish a high-content image platform based on the neurite outgrowth of dorsal root ganglia (DRG)-derived neuron cells for the discovery of neuroprotective agents against paclitaxel-induced CIPN. ND7/23 cells, an immortalized hybrid DRG cell line, were maturely differentiated by induction with nerve growth factor and upregulation of intracellular cAMP levels. High-content image analyses of the neurofilament-stained neurite network showed that paclitaxel disrupted the neurite outgrowth of well-differentiated ND7/23 DRG neuron cells, recapitulating characteristic effects of paclitaxel on primary cultured DRG neurons. This process coincided with the upregulated activity of store-operated Ca²⁺ entry, similar to those found in rodent models of paclitaxel-induced CIPN. The previously identified neuroprotective agents, minoxidil and 8-Br-cyclic adenosine monophosphate ribose (8-Br-cADPR), attenuated the reduction in total neurite outgrowth in paclitaxel-damaged ND7/23 cells. Additionally, the total neurite outgrowth of well-differentiated ND7/23 cells was concentration-dependently reduced by the neurotoxic chemotherapeutic agents, oxaliplatin and bortezomib, but not the less neurotoxic 5-fluorouracil. We demonstrated that high-content analyses of neurite morphology in well-differentiated DRG neuron-derived cells provide an effective, reproducible, and high-throughput strategy for developing therapeutics against CIPN.

Metabolic and lifestyle risk factors for chemotherapy-induced peripheral neuropathy in taxane and platinum-treated patients: a systematic review

PURPOSE

Chemotherapy-induced peripheral neurotoxicity (CIPN) is a common dose-limiting toxicity of cancer treatment causing functional impairment and impacting quality of life. Effective prevention and treatment of CIPN are lacking, and CIPN risk factors remain ill-defined. Metabolic syndrome and associated conditions have emerged as potential risk factors, due to their high prevalence and independent association with nerve dysfunction. This systematic review aimed to investigate the association between these common metabolic-lifestyle factors and CIPN.

METHODS

Searches were undertaken using Medline, Embase, CINAHL, Scopus, and Web of Science databases, with additional studies identified from bibliographic references cited by original and review articles. Articles that analyzed metabolic-lifestyle risk factors associated with CIPN for patients treated with platinum- or taxane-based chemotherapy were included.

RESULTS

Searches identified 6897 titles; 44 articles had full text review, with 26 studies included. Overall incidence of neuropathy ranged from 16.9 to 89.4%. Obesity had the most consistent patient-oriented evidence as a risk factor for CIPN, with moderate evidence suggesting diabetes did not increase CIPN incidence or severity. A limited number of studies supported an association with low physical activity and greater CIPN risk.

CONCLUSIONS

Comorbidities and lifestyle factors, particularly obesity and low physical activity, may contribute to the development of CIPN. The implementation of sensitive outcome measures in large-scale clinical trials is required to further elucidate CIPN risk factors and evaluate if changes in lifestyle would improve long-term CIPN outcomes for cancer survivors.

IMPLICATIONS FOR CANCER SURVIVORS

Better understanding of CIPN risk profiles may inform personalized medicine strategies and help elucidate pathophysiological mechanisms which could be targeted for neuroprotection.

Inhibitors of the Mechanistic Target of Rapamycin Can Ameliorate Bortezomib-Induced Peripheral Neuropathy

Bortezomib, an anticancer drug for multiple myeloma and mantle cell lymphoma, causes severe adverse events and leads to peripheral neuropathy. The associated neuropathy limits the use of bortezomib and could lead to discontinuation of the treatment; therefore, effective intervention is crucial. In the present study, we statistically searched for a drug that could alleviate bortezomib-induced peripheral neuropathy using adverse event self-reports. We observed that specific inhibitors of the mechanistic target of rapamycin (mTOR) lowered the incidence of bortezomib-induced peripheral neuropathy. These findings were experimentally validated in mice, which exhibited long-lasting mechanical hypersensitivity after repeated bortezomib treatment. This effect was inhibited for hours after a systemic injection with rapamycin or everolimus in a dose-dependent manner. Bortezomib-induced allodynia was accompanied by the activation of spinal astrocytes, and intrathecal injection of mTOR inhibitors or an inhibitor of ribosomal protein S6 kinase 1, a downstream target of mTOR, exhibited considerable analgesic effects in a dose-dependent manner. These results suggest that mTOR inhibitors, which are readily available to patients prescribed bortezomib, are one of the most effective therapeutics for bortezomib-induced peripheral neuropathy.

Dose-dependent immunomodulatory effects of bortezomib in experimental autoimmune neuritis

Proteasome inhibition with bortezomib has been reported to exert an immunomodulatory action in chronic autoimmune neuropathies. However, bortezomib used for the treatment of multiple myeloma induces a painful toxic polyneuropathy at a higher concentration. Therefore, we addressed this controversial effect and evaluated the neurotoxic and immunomodulatory mode of action of bortezomib in experimental autoimmune neuritis. Bortezomib-induced neuropathy was investigated in Lewis rats using the von Frey hair test, electrophysiological, qPCR and histological analyses of the sciatic nerve as well as dorsal root ganglia outgrowth studies. The immunomodulatory potential of bortezomib was characterized in Lewis rats after experimental autoimmune neuritis induction with P2_53-78 peptide. Clinical, electrophysiological, histological evaluation, von Frey hair test, flow cytometric and mRNA analyses were used to unravel the underlying mechanisms. We defined the toxic concentration of 0.2 mg/kg bortezomib applied intraperitoneally at Days 0, 4, 8 and 12. This dosage induces a painful toxic neuropathy but preserves axonal regeneration in vitro. Bortezomib at a concentration of 0.05 mg/kg significantly ameliorated experimental autoimmune neuritis symptoms, improved experimental autoimmune neuritis-induced hyperalgesia and nerve conduction studies, and reduced immune cell infiltration. Furthermore, proteasome inhibition induced a transcriptional downregulation of Nfkb in the sciatic nerve, while its inhibitor Ikba (also known as Nfkbia) was upregulated. Histological analyses of bone marrow tissue revealed a compensatory increase of CD138⁺ plasma cells. Our data suggest that low dose bortezomib (0.05 mg/kg intraperitoneally) has an immunomodulatory effect in the context of experimental autoimmune neuritis through proteasome inhibition and downregulation of nuclear factor 'kappa-light-chain-enhancer' of activated B-cells (NFKB). Higher bortezomib concentrations (0.2 mg/kg intraperitoneally) induce sensory neuropathy; however, the regeneration potential remains unaffected. Our data empathizes that bortezomib may serve as an attractive treatment option for inflammatory neuropathies in lower concentrations.

Clinical significance of SIRT3 and inflammatory factors in multiple myeloma patients with bortezomib-induced peripheral neuropathy: a cohort study

The present study aimed to investigate the role of SIRT3 and inflammatory factors in bortezomib-induced peripheral neuropathy (PN). This prospective observational cohort study included a total of 159 patients of multiple myeloma patients during June 2016 to June 2019. All patients received the strategy of bortezomib and dexamethasone and were further divided into the PN group and the non-PN group. Serum SIRT3, CRP, IL-6 and TNF-α levels were measured by enzyme-linked immunosorbent assay (ELISA). During the study period, 76 (47.8%) patients developed PN. The inflammatory factors all gradually decreased and SIRT3 levels were gradually increased after treatment by bortezomib combined with dexamethasone compared with the baseline. The levels of all inflammatory factors were markedly higher, while SIRT3 levels were lower in PN patients compared with the non-PN patients at the same time point after treatment. In PN grade III patients, the serum levels of CRP, IL-6 and TNF-α were significantly higher, while serum levels of SIRT3 were markedly lower than the grade I-II patients. SIRT3 was negatively correlated with CRP, IL-6 and TNF-α. After nursing treatment and reduction of bortezomib dose, the levels of SIRT3 significantly increased, while levels of inflammatory decreased in PN patients with grade III. SIRT3 and inflammatory factors showed the potential for diagnosis of bortezomib-induced PN. Besides, SIRT3, IL-6 and TNF-α were the independent risk factors for MM patients developing PN after treatment of bortezomib. Higher inflammatory factors and lower SIRT3 might be associated with the development of bortezomib-induced PN in multiple myeloma patients, which might be reversed by decreased bortezomib dose and proper nursing treatment.

Iatrogenic immune-mediated neuropathies: diagnostic, epidemiological and mechanistic uncertainties for causality and implications for clinical practice

Acute and chronic immune-mediated neuropathies have been widely reported with medical intervention. Although causal relationship may be uncertain in many cases, a variety of drugs, several vaccination types, surgical procedures and bone marrow transplants have been reported as possible cause or trigger of a putative immune-mediated response resulting in acute and chronic neuropathies. We conducted a systematic review of the literature from 1966 to 2020 on reported cases of possible iatrogenic immune-mediated neuropathies. We determined in each case the likelihood of causality based on frequency of the association, focusing primarily on clinical presentation and disease course as well as available ancillary investigations (electrophysiology, blood and cerebrospinal fluid and neuropathology). The response to immunotherapy and issue of re-exposure were also evaluated. We also considered hypothesised mechanisms of onset of immune-mediated neuropathy in the specific iatrogenic context. We believe that a likely causal relationship exists for only few drugs, mainly antitumour necrosis factor alpha agents and immune checkpoint inhibitors, but remains largely unsubstantiated for most other suggested iatrogenic causes. Unfortunately, given the lack of an accurate diagnostic biomarker for most immune-mediated neuropathies, clinical assessment will often override ancillary investigations, resulting in lower levels of certainty that may continue to cast serious doubts on reliability of their diagnosis. Consequently, future reports of suspected cases should collect and exhaustively assess all relevant data. At the current time, besides lack of evidence for causality, the practical implications on management of suspected cases is extremely limited and therapeutic decisions appear likely no different to those made in non-iatrogenic cases.

The molecular and cellular insight into the toxicology of bortezomib-induced peripheral neuropathy

The proteasome inhibitor bortezomib (BTZ) is a first-line antitumor drug, mainly used for multiple myeloma treatment. However, BTZ shows prominent toxicity in the peripheral nervous system, termed BTZ-induced peripheral neuropathy (BIPN). BIPN is characterized by neuropathic pain, resulting in a dose reduction or even treatment withdrawal. To date, the pathological mechanism of BIPN has not been elucidated. There is still no effective strategy to prevent or treat BIPN. This review summarizes the pathological mechanisms of BIPN, which involves the pathological changes of Schwann cells, neurons, astrocytes and macrophages. A better knowledge of the pathological mechanisms of BIPN would provide new ideas for therapeutic interventions of BIPN patients.

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.

Review Article "Spotlight on Ultrasonography in the Diagnosis of Peripheral Nerve Disease: The Evidence to Date"

Neuromuscular ultrasound is rapidly becoming incorporated into clinical practice as a standard tool in the assessment of peripheral nerve diseases. Ultrasound complements clinical phenotyping and electrodiagnostic evaluation, providing critical structural anatomical information to enhance diagnosis and identify structural pathology. This review article examines the evidence supporting neuromuscular ultrasound in the diagnosis of compressive mononeuropathies, traumatic nerve injury, generalised peripheral neuropathy and motor neuron disease. Extending the sonographic evaluation of nerves beyond simple morphological measurements has the potential to improve diagnostics in peripheral neuropathy, as well as advancing the understanding of pathological mechanisms, which in turn will promote precise therapies and improve therapeutic outcomes.

Prevalence of Chemotherapy-Induced Peripheral Neuropathy in Multiple Myeloma Patients and its Impact on Quality of Life: A Single Center Cross-Sectional Study

Bortezomib is a pivotal drug for the management of multiple myeloma. However, bortezomib is a neurotoxic anticancer drug responsible for chemotherapy-induced peripheral neuropathy (CIPN). CIPN is associated with psychological distress and a decrease of health-related quality of life (HRQoL), but little is known regarding bortezomib-related CIPN. This single center, cross-sectional study assessed the prevalence and severity of sensory/motor CIPN, neuropathic pain and ongoing pain medications, anxiety, depression, and HRQoL, in multiple myeloma patients after the end of bortezomib treatment. Paper questionnaires were sent to patients to record the scores of sensory and motor CIPNs (QLQ-CIPN20), neuropathic pain (visual analogue scale and DN4 interview), anxiety and depression (HADS), the scores of HRQoL (QLQ-C30 and QLQ-MY20) and ongoing pain medications. Oncological data were recorded using chemotherapy prescription software and patient medical records. The prevalence of sensory CIPN was 26.9% (95% CI 16.7; 39.1) among the 67 patients analyzed and for a mean time of 2.9 ± 2.8 years since the last bortezomib administration. The proportion of sensory CIPN was higher among patients treated by intravenous and subcutaneous routes than intravenous or subcutaneous routes (p = 0.003). QLQ-CIPN20 motor scores were higher for patients with a sensory CIPN than those without (p < 0.001) and were correlated with the duration of treatment and the cumulative dose of bortezomib (coefficient: 0.31 and 0.24, p = 0.01 and 0.0475, respectively), but not sensory scores. Neuropathic pain was screened in 44.4% of patients with sensory CIPN and 66.7% of them had ongoing pain medications, but none were treated with duloxetine (recommended drug). Multivariable analysis revealed that thalidomide treatment (odds-ratio: 6.7, 95% CI 1.3; 35.5, p = 0.03) and both routes of bortezomib administration (odds-ratio: 13.4, 95% CI 1.3; 139.1, p = 0.03) were associated with sensory CIPN. Sensory and motor CIPNs were associated with anxiety, depression, and deterioration of HRQoL. Sensory CIPN was identified in a quarter of patients after bortezomib treatment and associated with psychological distress that was far from being treated optimally. There is a need to improve the management of patients with CIPN, which may include better training of oncologists regarding its diagnosis and pharmacological treatment.

Comparison of efficacy, safety, patients' quality of life, and doctors' occupational stress between lenalidomide-based and bortezomib-based induction in patients with newly diagnosed multiple myeloma

BACKGROUND

In the new therapeutic era, comparisons between regimens containing lenalidomide and bortezomib are needed.

METHODS

In this single-center, prospective study, patients received four to six cycles of lenalidomide+liposomal doxorubicin+dexamethasone (RAD) or bortezomib+liposomal doxorubicin+dexamethasone (PAD) every 4 weeks, with subsequent autologous stem cell transplantation (ASCT) and maintenance therapy. We compared the efficacy, safety, patients' quality of life, and doctors' occupational stress between RAD and PAD induction in newly diagnosed MM patients.

RESULTS

The complete response (CR) rate was comparable between the RAD and PAD groups after induction (30.8% vs. 32.0%, p = 0.92). Common adverse events, including infections, peripheral neuropathy, and gastrointestinal disturbances, were more frequent in the PAD group, while leukopenia and rashes were more common in the RAD group. Compared with PAD, RAD improved patients' quality of life more quickly and caused less occupational stress for doctors. However, only 31.6% of patients collected adequate CD34+ cells (≥2 × 10⁶ /kg) in the RAD group, which was significantly lower than that in the PAD group (95.5%, p < 0.001). The number of CD34+ cells collected was significantly higher in patients within three courses of RAD than in patients with four or five to six courses (14.18 ± 13.57 vs. 2.07 ± 2.42 vs. 1.51 ± 1.81 × 10⁶ /kg, p = 0.028). The median progression-free survival and overall survival of the two groups were not reached by the end of follow-up.

CONCLUSION

Compared to PAD, RAD induction had comparable efficacy and a significantly better safety profile, improved quality of life for patients, and reduced occupational stress for doctors. However, RAD induction may need to be limited to four cycles to avoid irreversible damage to hematopoietic stem cells.

CLINICAL TRIAL REGISTRATION

This study was registered at www.chictr.org.cn (ChiCTR1900021558).

Multiple myeloma-A painful disease of the bone marrow

Multiple myeloma is a bone marrow neoplasia with an incidence of 6/100,000/year in Europe. While the disease remains incurable, the development of novel treatments such as autologous stem cell transplantation, proteasome inhibitors and monoclonal antibodies has led to an increasing subset of patients living with long-term myeloma. However, more than two thirds of patients suffer from bone pain, often described as severe, and knowledge on the pain mechanisms and its effect on their health-related quality of life (HRQoL) is limited. In this review, we discuss the mechanisms of myeloma bone disease, the currently available anti-myeloma treatments and the lessons learnt from clinical studies regarding HRQoL in myeloma patients. Moreover, we discuss the mechanisms of cancer-induced bone pain and the knowledge that animal models of myeloma-induced bone pain can provide to identify novel analgesic targets. To date, information regarding bone pain and HRQoL in myeloma patients is still scarce and an effort should be made to use standardised questionnaires to assess patient-reported outcomes that allow inter-study comparisons of the available clinical data.

Non-Hematologic Toxicity of Bortezomib in Multiple Myeloma: The Neuromuscular and Cardiovascular Adverse Effects

Simple Summary

Multiple myeloma (MM) is a still uncurable tumor of mainly elderly patients originating from the terminally differentiated B cells. Introduction to the treatment of MM patients of a new class of drugs called proteasome inhibitors (bortezomib followed by carfilzomib and ixazomib) significantly improved disease control. Proteasome inhibitors interfere with the major mechanism of protein degradation in a cell leading to the severe imbalance in the protein turnover that is deadly to MM cells. Currently, these drugs are the mainstream of MM therapy but are also associated with an increased rate of the injuries to multiple organs and tissues. In this review, we summarize the current knowledge on the molecular mechanisms of the first-in-class proteasome inhibitor bortezomib-induced disturbances in the function of peripheral nerves and cardiac and skeletal muscle.

Abstract

The overall approach to the treatment of multiple myeloma (MM) has undergone several changes during the past decade. and proteasome inhibitors (PIs) including bortezomib, carfilzomib, and ixazomib have considerably improved the outcomes in affected patients. The first-in-class selective PI bortezomib has been initially approved for the refractory forms of the disease but has now become, in combination with other drugs, the backbone of the frontline therapy for newly diagnosed MM patients, as well as in the maintenance therapy and relapsed/refractory setting. Despite being among the most widely used and highly effective agents for MM, bortezomib can induce adverse events that potentially lead to early discontinuation of the therapy with negative effects on the quality of life and outcome of the patients. Although peripheral neuropathy and myelosuppression have been recognized as the most relevant bortezomib-related adverse effects, cardiac and skeletal muscle toxicities are relatively common in MM treated patients, but they have received much less attention. Here we review the neuromuscular and cardiovascular side effects of bortezomib. focusing on the molecular mechanisms underlying its toxicity. We also discuss our preliminary data on the effects of bortezomib on skeletal muscle tissue in mice receiving the drug.

Long-Term Prevalence of Sensory Chemotherapy-Induced Peripheral Neuropathy for 5 Years after Adjuvant FOLFOX Chemotherapy to Treat Colorectal Cancer: A Multicenter Cross-Sectional Study

(1) Background: Oxaliplatin is among the most neurotoxic anticancer drugs. Little data are available on the long-term prevalence and consequences of chemotherapy-induced peripheral neuropathy (CIPN), even though the third largest population of cancer survivors is made up of survivors of colorectal cancer. (2) Methods: A multicenter, cross-sectional study was conducted in 16 French centers to assess the prevalence of CIPN, as well as its consequences (neuropathic pain, anxiety, depression, and quality of life) in cancer survivors during the 5 years after the end of adjuvant oxaliplatin chemotherapy. (3) Results: Out of 406 patients, the prevalence of CIPN was 31.3% (95% confidence interval: 26.8–36.0). Little improvement in CIPN was found over the 5 years, and 36.5% of patients with CIPN also had neuropathic pain. CIPN was associated with anxiety, depression, and deterioration of quality of life. None of the patients with CIPN were treated with duloxetine (recommendation from American Society of Clinical Oncology), and only 3.2%, 1.6%, and 1.6% were treated with pregabalin, gabapentin, and amitriptyline, respectively. (4) Conclusions: Five years after the end of chemotherapy, a quarter of patients suffered from CIPN. The present study showed marked psychological distress and uncovered a failure in management in these patients.

Exploring the RC-106 Chemical Space: Design and Synthesis of Novel (E)-1-(3-Arylbut-2-en-1-yl)-4-(Substituted) Piperazine Derivatives as Potential Anticancer Agents

Despite the fact that significant advances in treatment of common cancers have been achieved over the years, orphan tumors still represent an important unmet medical need. Due to their complex multifactorial origin and limited number of cases, such pathologies often have very limited treatment options and poor prognosis. In the search for new anticancer agents, our group recently identified RC-106, a Sigma receptor modulator endowed with proteasome inhibition activity. This compound showed antiproliferative activity toward different cancer cell lines, among them glioblastoma (GB) and multiple myeloma (MM), two currently unmet medical conditions. In this work, we directed our efforts toward the exploration of chemical space around RC-106 to identify new active compounds potentially useful in cancer treatment. Thanks to a combinatorial approach, we prepared 41 derivatives of the compound and evaluated their cytotoxic potential against MM and GB. Three novel potential anticancer agents have been identified.