Current use of fluid biomarkers as outcome measures in Multiple Sclerosis (MS): a review of ongoing pharmacological clinical trials

The present study aims to describe the state of the art of fluid biomarkers use in ongoing multiple sclerosis (MS) clinical trials.A review of 608 ongoing protocols in the clinicaltrials.gov and EudraCT databases was performed. The trials enrolled patients with a diagnosis of relapsing remitting MS, secondary progressive MS, and/or primary progressive MS according to Revised McDonald criteria or relapsing MS according to Lublin et al. (2014). The presence of fluid biomarkers among the primary and/or secondary study outcomes was assessed.Overall, 5% of ongoing interventional studies on MS adopted fluid biomarkers. They were mostly used as secondary outcomes in phase 3-4 clinical trials to support the potential disease-modifying properties of the intervention. Most studies evaluated neurofilament light chains (NfLs). A small number considered other novel fluid biomarkers of neuroinflammation and neurodegeneration such as glial fibrillary acid protein (GFAP).Considering the numerous ongoing clinical trials in MS, still a small number adopted fluid biomarkers as outcome measures, thus testifying the distance from clinical practice. In most protocols, fluid biomarkers were used to evaluate the effectiveness of approved second-line therapies, but also, new drugs (particularly Bruton kinase inhibitors). NfLs were also adopted to monitor disease progression after natalizumab suspension in stable patients, cladribine efficacy after anti-CD20 discontinuation, and the efficacy of autologous hematopoietic stem cell transplant (AHSCT) compared to medical treatment. Nevertheless, further validation studies are needed for all considered fluid biomarkers to access clinical practice, and cost-effectiveness in the "real word" remains to be clarified.

Impact of 2021 European Academy of Neurology/Peripheral Nerve Society diagnostic criteria on diagnosis and therapy of chronic inflammatory demyelinating polyradiculoneuropathy variants

BACKGROUND AND PURPOSE

There are different criteria for the diagnosis of different variants of chronic inflammatory demyelinating polyradiculoneuropathy (CIDP). The 2021 European Academy of Neurology/Peripheral Nerve Society (EAN/PNS) guidelines provide specific clinical criteria for each CIDP variant even if their therapeutical impact has not been investigated.

METHODS

We applied the clinical criteria for CIDP variants of the 2021 EAN/PNS guidelines to 369 patients included in the Italian CIDP database who fulfilled the 2021 EAN/PNS electrodiagnostic criteria for CIDP.

RESULTS

According to the 2021 EAN/PNS clinical criteria, 245 patients achieved a clinical diagnosis of typical CIDP or CIDP variant (66%). We identified 106 patients with typical CIDP (29%), 62 distal CIDP (17%), 28 multifocal or focal CIDP (7%), four sensory CIDP (1%), 27 sensory-predominant CIDP (7%), 10 motor CIDP (3%), and eight motor-predominant CIDP (2%). Patients with multifocal, distal, and sensory CIDP had milder impairment and symptoms. Patients with multifocal CIDP had less frequently reduced conduction velocity and prolonged F-wave latency and had lower levels of cerebrospinal fluid protein. Patients with distal CIDP more frequently had reduced distal compound muscle action potentials. Patients with motor CIDP did not improve after steroid therapy, whereas those with motor-predominant CIDP did. None of the patients with sensory CIDP responded to steroids, whereas most of those with sensory-predominant CIDP did.

CONCLUSIONS

The 2021 EAN/PNS criteria for CIDP allow a better characterization of CIDP variants, permitting their distinction from typical CIDP and more appropriate treatment for patients.

Mobile Applications to Support Multiple Sclerosis Communities: The Post-COVID-19 Scenario

Introduction: The increase in the use of mobile apps since the COVID-19 pandemic, even among people with multiple sclerosis (PwMS) and health care providers (HCPs), has enabled access to reliable information, symptoms monitoring and management, and social connections. The pandemic has undoubtedly contributed to the acceleration of the "digital revolution." But how far has it progressed for the MS communities? Methods: Italian Google Play and App Store were queried, selecting MS-specific apps in English or Italian language and usable by a wide public. Results: Fifty-four (n = 54) MS-specific apps were identified; most were PwMS-oriented (83%), free of charge (94%), and in English language (76%). The 45 PwMS-oriented apps focused on increasing MS knowledge (71%), tracking symptoms (33%), and promoting networking with peers or HCPs (38%). The 13 HCPs-oriented tools addressed education and updates on MS (62%), disease assessment and management (54%), and research (15%). Google Search tool was also queried to find non-MS-specific apps to fulfill some unmet domains (as sleep, pain, sexual or mental health). Twenty-four additional apps were listed to provide a valuable contribution. Conclusion: The "digital revolution" led to increasingly customized tools for PwMS, especially as m-health or social-networking apps. However, apps to support other specific MS-relevant domains, appealing HCPs-oriented apps, and specific mobile tools for MS caregivers are still lacking. The absence of data assessing the usability and quality of MS apps in ecologically contexts leads to not reliable conclusions about potential benefits. A strong dialogue between MS communities and the digital industry is encouraged to fill this gap.

Morphofunctional characterisation of axonal damage in different rat models of chemotherapy-induced peripheral neurotoxicity: The role of nerve excitability testing

BACKGROUND AND AIMS

Chemotherapy-induced peripheral neurotoxicity (CIPN) is a common and long-lasting adverse event of several anticancer compounds, for which treatment has not yet been developed. To fill this gap, preclinical studies are warranted, exploiting highly translational outcome measure(s) to transfer data from bench to bedside. Nerve excitability testing (NET) enables to test in vivo axonal properties and can be used to monitor early changes leading to axonal damage.

METHODS

We tested NET use in two different CIPN rat models: oxaliplatin (OHP) and paclitaxel (PTX). Animals (female) were chronically treated with either PTX or OHP and compared to respective control animals. NET was performed as soon as the first injection was administered. At the end of the treatment, CIPN onset was verified via a multimodal and robust approach: nerve conduction studies, nerve morphometry, behavioural tests and intraepidermal nerve fibre density.

RESULTS

NET showed the typical pattern of axonal hyperexcitability in the 72 h following the first OHP administration, whereas it showed precocious signs of axonal damage in PTX animals. At the end of the month of treatment, OHP animals showed a pattern compatible with a mild axonal sensory polyneuropathy. Instead, PTX cohort was characterised by a rather severe sensory axonal polyneuropathy with minor signs of motor involvement.

INTERPRETATION

NET after the first administration demonstrated the ongoing OHP-related channelopathy, whereas in PTX cohort it showed precocious signs of axonal damage. Therefore, NET could be suggested as an early surrogate marker in clinical trials, to detect precocious changes leading to axonal damage.

Effect of age on metabolomic changes in a model of paclitaxel-induced peripheral neurotoxicity

BACKGROUND AND AIMS

Chemotherapy-induced peripheral neurotoxicity (CIPN) is one of the most common dose-limiting side effects of paclitaxel (PTX) treatment. Many age-related changes have been hypothesized to underlie susceptibility to damage or impaired regeneration/repair after nerve injury. The results of these studies, however, are inconclusive and other potential biomarkers of nerve impairment need to be investigated.

METHODS

Twenty-four young (2 months) and 24 adult (9 months) Wistar male rats were randomized to either PTX treatment (10 mg/kg i.v. once/week for 4 weeks) or vehicle administration. Neurophysiological and behavioral tests were performed at baseline, after 4 weeks of treatment and 2-week follow-up. Skin biopsies and nerve specimens collected from sacrificed animals were examined for intraepidermal nerve fiber (IENF) density assessment and nerve morphology/morphometry. Blood and liver samples were collected for targeted metabolomics analysis.

RESULTS

At the end of treatment, the neurophysiological studies revealed a reduction in sensory nerve action potential amplitude (p < .05) in the caudal nerve of young PTX-animals, and in both the digital and caudal nerve of adult PTX-animals (p < .05). A significant decrease in the mechanical threshold was observed only in young PTX-animals (p < .001), but not in adult PTX-ones. Nevertheless, both young and adult PTX-rats had reduced IENF density (p < .0001), which persisted at the end of follow-up period. Targeted metabolomics analysis showed significant differences in the plasma metabolite profiles between PTX-animals developing peripheral neuropathy and age-matched controls, with triglycerides, diglycerides, acylcarnitines, carnosine, long chain ceramides, sphingolipids, and bile acids playing a major role in the response to PTX administration.

INTERPRETATION

Our study identifies for the first time multiple related metabolic axes involved in PTX-induced peripheral neurotoxicity, and suggests age-related differences in CIPN manifestations and in the metabolic profile.

Evaluation of drivers of treatment switch in relapsing multiple sclerosis: a study from the Italian MS Registry

BACKGROUND

Active relapsing-remitting (RR) and secondary progressive (SP) multiple sclerosis (MS) are currently defined as "relapsing MS" (RMS). The aim of this cross-sectional study was to assess drivers of treatment switches due to clinical relapses in a population of RMS patients collected in the Italian MS and Related Disorders Register (I-MS&RD).

METHODS

RRMS and SPMS patients with at least one relapse in a time window of 2 years before of data extraction were defined as RMS. Factors associated with disease-modifying therapy (DMT) switching due to clinical activity were assessed through multivariable logistic regression models in which treatment exposure was included as the last recorded DMT and the last DMT's class [moderate-efficacy (ME), high-efficacy (HE) DMTs and anti-CD20 drugs].

RESULTS

A cohort of 4739 RMS patients (4161 RRMS, 578 SPMS) was extracted from the I-MS&RD. A total of 2694 patients switching DMTs due to relapses were identified. Switchers were significantly (p < 0.0001) younger, less disabled, more frequently affected by an RR disease course in comparison to non-switcher patients. The multivariable logistic regression models showed that Alemtuzumab (OR 0.08, 95% CI 0.02-0.37), Natalizumab (0.48, 0.30-0.76), Ocrelizumab (0.1, 0.02-0.45) and Rituximab (0.23, 0.06-0.82) exposure was a protective factor against treatment switch due to relapses. Moreover, the use of HE DMTs (0.43, 0.31-0.59), especially anti-CD20 drugs (0.14, 0.05-0.37), resulted to be a protective factor against treatment switch due to relapses in comparison with ME DMTs.

CONCLUSIONS

More than 50% of RMS switched therapy due to disease activity. HE DMTs, especially anti-CD20 drugs, significantly reduce the risk of treatment switch.

Vincristine Disposition and Neurotoxicity Are Unchanged in Humanized CYP3A5 Mice

Previous studies have suggested that the incidence of vincristine-induced peripheral neuropathy (VIPN) is potentially linked with cytochrome P450 (CYP)3A5, a polymorphic enzyme that metabolizes vincristine in vitro, and with concurrent use of azole antifungals such as ketoconazole. The assumed mechanism for these interactions is through modulation of CYP3A-mediated metabolism, leading to decreased vincristine clearance and increased susceptibility to VIPN. Given the controversy surrounding the contribution of these mechanisms, we directly tested these hypotheses in genetically engineered mouse models with a deficiency of the entire murine Cyp3a locus [Cyp3a(-/-) mice] and in humanized transgenic animals with hepatic expression of functional and nonfunctional human CYP3A5 variants. Compared with wild-type mice, the systemic exposure to vincristine was increased by only 1.15-fold (95% confidence interval, 0.84-1.58) in Cyp3a(-/-) mice, suggesting that the clearance of vincristine in mice is largely independent of hepatic Cyp3a function. In line with these observations, we found that Cyp3a deficiency or pretreatment with the CYP3A inhibitors ketoconazole or nilotinib did not influence the severity and time course of VIPN and that exposure to vincristine was not substantially altered in humanized CYP3A5*3 mice or humanized CYP3A5*1 mice compared with Cyp3a(-/-) mice. Our study suggests that the contribution of CYP3A5-mediated metabolism to vincristine elimination and the associated drug-drug interaction potential is limited and that plasma levels of vincristine are unlikely to be strongly predictive of VIPN. SIGNIFICANCE STATEMENT: The current study suggests that CYP3A5 genotype status does not substantially influence vincristine disposition and neurotoxicity in translationally relevant murine models. These findings raise concerns about the causality of previously reported relationships between variant CYP3A5 genotypes or concomitant azole use with the incidence of vincristine neurotoxicity.

TWIST1 Upregulation Is a Potential Target for Reversing Resistance to the CDK4/6 Inhibitor in Metastatic Luminal Breast Cancer Cells

Cyclin-dependent kinase (CDK) 4/6 inhibitors have significantly improved progression-free survival in hormone-receptor-positive (HR+), human-epidermal-growth-factor-receptor-type-2-negative (HER2-) metastatic luminal breast cancer (mLBC). Several studies have shown that in patients with endocrine-sensitive or endocrine-resistant LBC, the addition of CDK4/6 inhibitors to endocrine therapy significantly prolongs progression-free survival. However, the percentage of patients who are unresponsive or refractory to these therapies is as high as 40%, and no reliable and reproducible biomarkers have been validated to select a priori responders or refractory patients. The selection of mutant clones in the target oncoprotein is the main cause of resistance. Other mechanisms such as oncogene amplification/overexpression or mutations in other pathways have been described in several models. In this study, we focused on palbociclib, a selective CDK4/6 inhibitor. We generated a human MCF-7 luminal breast cancer cell line that was able to survive and proliferate at different concentrations of palbociclib and also showed cross-resistance to abemaciclib. The resistant cell line was characterized via RNA sequencing and was found to strongly activate the epithelial-to-mesenchymal transition. Among the top deregulated genes, we found a dramatic downregulation of the CDK4 inhibitor CDKN2B and an upregulation of the TWIST1 transcription factor. TWIST1 was further validated as a target for the reversal of palbociclib resistance. This study provides new relevant information about the mechanisms of resistance to CDK4/6 inhibitors and suggests potential new markers for patients' follow-up care during treatment.

Axonal degeneration in chemotherapy-induced peripheral neurotoxicity: clinical and experimental evidence

Multiple pathological mechanisms are involved in the development of chemotherapy-induced peripheral neurotoxicity (CIPN). Recent work has provided insights into the molecular mechanisms underlying chemotherapy-induced axonal degeneration. This review integrates evidence from preclinical and clinical work on the onset, progression and outcome of axonal degeneration in CIPN. We review likely triggers of axonal degeneration in CIPN and highlight evidence of molecular pathways involved in axonal degeneration and their relevance to CIPN, including SARM1-mediated axon degeneration pathway. We identify potential clinical markers of axonal dysfunction to provide early identification of toxicity as well as present potential treatment strategies to intervene in axonal degeneration pathways. A greater understanding of axonal degeneration processes in CIPN will provide important information regarding the development and progression of axonal dysfunction more broadly and will hopefully assist in the development of successful interventions for CIPN and other neurodegenerative disorders.

Toxic medications in Charcot-Marie-Tooth patients: A systematic review

BACKGROUND AND AIMS

Several widely used medications, with a relevant efficacy profile, are toxic to the peripheral nervous system and an even larger number of agents are suspected to be neurotoxic. There are concerns about the use of these drugs in patients with Charcot-Marie-Tooth disease (CMT), a hereditary motor and sensory neuropathy. This review provides evidence-based updated recommendations on this clinically relevant topic.

METHODS

A systematic review of the available studies/reports written in English was performed from July to September 2022 including in the search string all reported putative neurotoxic drugs.

RESULTS

The results of our systematic review provide evidence-based support for the statement that use of vincristine, and possibly paclitaxel, can occasionally induce an atypical, and more severe, course of drug-related peripheral neurotoxicity in CMT patients. It is therefore reasonable to recommend caution in the use of these compounds in CMT patients. However, no convincing evidence for a similar recommendation could be found for all other drugs.

INTERPRETATION

It is important that patients with CMT are not denied effective treatments that may prolong life expectancy for cancer or improve their health status if affected by non-oncological diseases. Accurate monitoring of peripheral nerve function in CMT patients treated with any neurotoxic agent remains mandatory to detect the earliest signs of neuropathy worsening and atypical clinical courses. Neurologists monitoring CMT patients as part of their normal care package or for natural history studies should keep detailed records of exposures to neurotoxic medications and support reporting of accelerated neuropathy progression if observed.

Studies to Assess the Utility of Serum Neurofilament Light Chain as a Biomarker in Chemotherapy-Induced Peripheral Neuropathy

Chemotherapy-induced peripheral neuropathy (CIPN) is one of the most common and disabling dose-limiting toxicities of chemotherapy. We report here the results of two separate non-interventional studies (49 patients), which evaluated blood neurofilament light chain (NfL) as a biomarker of CIPN in breast cancer patients treated with paclitaxel. All patients underwent a standard treatment protocol that was established independently of the present studies. NfL was measured in serum using an ultrasensitive single-molecule array and compared with the self-administered European Organization for Research and Treatment of Cancer Quality of Life Questionnaire-CIPN twenty-item scale (CIPN20) and Total Neuropathy Score clinical version (TNSc), a clinician-reported measure of neuropathy progression. The TNSc increased with cumulative dose compared with baseline, and the NfL concentrations were also strongly associated with the cumulative dose of chemotherapy. The analysis showed a correlation between TNSc and NfL. Both TNSc and NfL showed weak to moderate associations with CIPN20 subscores, with a better association for the CIPN20 sensory compared with motor and autonomic subscores. Data from the two studies provide evidence that serum NfL has the potential to be used as a biomarker to monitor and mitigate CIPN. However, studies with additional patients planned in the ongoing clinical trial will determine the universal application of NfL as a biomarker in CIPN.

Unclassified clinical presentations of chronic inflammatory demyelinating polyradiculoneuropathy

BACKGROUND

To assess the ability of the 2021 European Academy of Neurology/Peripheral Nerve Society (EAN/PNS) clinical criteria for chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) to include within their classification the whole spectrum of clinical heterogeneity of the disease and to define the clinical characteristics of the unclassifiable clinical forms.

METHODS

The 2021 EAN/PNS clinical criteria for CIDP were applied to 329 patients fulfilling the electrodiagnostic (and in some cases also the supportive) criteria for the diagnosis of CIDP. Clinical characteristics were reviewed for each patient not strictly fulfilling the clinical criteria ('unclassifiable').

RESULTS

At study inclusion, 124 (37.5%) patients had an unclassifiable clinical presentation, including 110 (89%) with a typical CIDP-like clinical phenotype in whom some segments of the four limbs were unaffected by weakness ('incomplete typical CIDP'), 10 (8%) with a mild distal, symmetric, sensory or sensorimotor polyneuropathy confined to the lower limbs with cranial nerve involvement ('cranial nerve predominant CIDP') and 4 (1%) with a symmetric sensorimotor polyneuropathy limited to the proximal and distal areas of the lower limbs ('paraparetic CIDP'). Eighty-one (65%) patients maintained an unclassifiable presentation during the entire disease follow-up while 13 patients progressed to typical CIDP. Patients with the unclassifiable clinical forms compared with patients with typical CIDP had a milder form of CIDP, while there was no difference in the distribution patterns of demyelination.

CONCLUSIONS

A proportion of patients with CIDP do not strictly fulfil the 2021 EAN/PNS clinical criteria for diagnosis. These unclassifiable clinical phenotypes may pose diagnostic challenges and thus deserve more attention in clinical practice and research.

Targeting a xenobiotic transporter to ameliorate vincristine-induced sensory neuropathy

Vincristine is a widely used chemotherapeutic drug for the treatment of multiple malignant diseases that causes a dose-limiting peripheral neurotoxicity. There is no clinically effective preventative treatment for vincristine-induced sensory peripheral neurotoxicity (VIPN), and mechanistic details of this side effect remain poorly understood. We hypothesized that VIPN is dependent on transporter-mediated vincristine accumulation in dorsal root ganglion neurons. Using a xenobiotic transporter screen, we identified OATP1B3 as a neuronal transporter regulating the uptake of vincristine. In addition, genetic or pharmacological inhibition of the murine orthologue transporter OATP1B2 protected mice from various hallmarks of VIPN - including mechanical allodynia, thermal hyperalgesia, and changes in digital maximal action potential amplitudes and neuronal morphology - without negatively affecting plasma levels or antitumor effects of vincristine. Finally, we identified α-tocopherol from an untargeted metabolomics analysis as a circulating endogenous biomarker of neuronal OATP1B2 function, and it could serve as a companion diagnostic to guide dose selection of OATP1B-type transport modulators given in combination with vincristine to prevent VIPN. Collectively, our findings shed light on the fundamental basis of VIPN and provide a rationale for the clinical development of transporter inhibitors to prevent this debilitating side effect.

Role of Mouse Organic Cation Transporter 2 for Nephro- and Peripheral Neurotoxicity Induced by Chemotherapeutic Treatment with Cisplatin

Cisplatin (CDDP) is an efficient chemotherapeutic agent broadly used to treat solid cancers. Chemotherapy with CDDP can cause significant unwanted side effects such as renal toxicity and peripheral neurotoxicity. CDDP is a substrate of organic cation transporters (OCT), transporters that are highly expressed in renal tissue. Therefore, CDDP uptake by OCT may play a role in causing unwanted toxicities of CDDP anticancer treatment. In this study, the contribution of the mouse OCT2 (mOCT2) to CDDP nephro- and peripheral neurotoxicity was investigated by comparing the effects of cyclic treatment with low doses of CDDP on renal and neurological functions in wild-type (WT) mice and mice with genetic deletion of OCT2 (OCT2-/- mice). This CDDP treatment protocol caused significant impairment of kidneys and peripherical neurological functions in WT mice. These effects were significantly reduced in OCT2-/- mice, however, less profoundly than what was previously measured in mice with genetic deletion of both OCT1 and 2 (OCT1-2-/- mice). Comparing the apparent affinities (IC50) of mOCT1 and mOCT2 for CDDP, the mOCT1 displayed a higher affinity for CDDP than the mOCT2 (IC50: 9 and 558 µM, respectively). Also, cellular toxicity induced by incubation with 100 µM CDDP was more pronounced in cells stably expressing mOCT1 than in cells expressing mOCT2. Therefore, in mice, CDDP uptake by both OCT1 and 2 contributes to the development of CDDP undesired side effects. OCT seem to be suitable targets for establishing treatment protocols aimed at decreasing unwanted CDDP toxicity and improving anticancer treatment with CDDP.

CSF Findings in Relation to Clinical Characteristics, Subtype, and Disease Course in Patients With Guillain-Barré Syndrome

BACKGROUND AND OBJECTIVES

To investigate CSF findings in relation to clinical and electrodiagnostic subtypes, severity, and outcome of Guillain-Barré syndrome (GBS) based on 1,500 patients in the International GBS Outcome Study.

METHODS

Albuminocytologic dissociation (ACD) was defined as an increased protein level (>0.45 g/L) in the absence of elevated white cell count (<50 cells/μL). We excluded 124 (8%) patients because of other diagnoses, protocol violation, or insufficient data. The CSF was examined in 1,231 patients (89%).

RESULTS

In 846 (70%) patients, CSF examination showed ACD, which increased with time from weakness onset: ≤4 days 57%, >4 days 84%. High CSF protein levels were associated with a demyelinating subtype, proximal or global muscle weakness, and a reduced likelihood of being able to run at week 2 (odds ratio [OR] 0.42, 95% CI 0.25-0.70; p = 0.001) and week 4 (OR 0.44, 95% CI 0.27-0.72; p = 0.001). Patients with the Miller Fisher syndrome, distal predominant weakness, and normal or equivocal nerve conduction studies were more likely to have lower CSF protein levels. CSF cell count was <5 cells/μL in 1,005 patients (83%), 5-49 cells/μL in 200 patients (16%), and ≥50 cells/μL in 13 patients (1%).

DISCUSSION

ACD is a common finding in GBS, but normal protein levels do not exclude this diagnosis. High CSF protein level is associated with an early severe disease course and a demyelinating subtype. Elevated CSF cell count, rarely ≥50 cells/μL, is compatible with GBS after a thorough exclusion of alternative diagnoses.

CLASSIFICATION OF EVIDENCE

This study provides Class IV evidence that CSF ACD (defined by the Brighton Collaboration) is common in patients with GBS.

Abstract P1-13-21: Loss of CDKN2B expression as a potential marker of resistance to CDK4/6 inhibitor in Luminal Breast Cancer cells

Background Cyclin-Dependent Kinase (CDK) 4/6 inhibitors have significantly improved progression-free survival of Hormone Receptor positive (HR+), Human Epidermal Growth Factor Receptor type 2 negative (HER2-) luminal breast cancers (LBC). Several studies demonstrated that the addition of CDK4/6 inhibitors to endocrine therapy results in a significant prolongation of progression-free survival in patients with endocrine-sensitive or endocrine-resistant LBCs. However, the percentage of patients unresponsive or refractory to these therapies is as high as 40%, and no reliable and reproducible biomarkers able to select a priori responder or resistant patients have been validated till now. The main cause of resistance is the selection of mutant clones in the target oncoprotein. Other mechanisms, like oncogene amplification/overexpression or mutations in other pathways, have been described in several models. Here, we focused on palbociclib, a selective inhibitor of CDK4/6. Methods: We generated and characterized human luminal breast cancer MCF-7 and T47D derived cell lines, able to survive and proliferate at different palbociclib concentrations, which also shows cross-resistance to abemaciclib. The resistant MCF7 cell line was characterized by RNA sequencing. Results: To confirm resistance, we performed cell viability assays in MCF-7 and T47D palbociclib sensitive cells (MCF-7pS and T47pS) versus MCF-7 and T47D palbociclib resistant cells (MCF-7pR5), showing a 10-fold increase of IC50 in MCF-7pR5 compared to parental MCF-7pS cells (16.7 vs 1.8 µM) and a 3-fold increase of IC50 in T47DpR5 vs parental T47DpS. We also confirmed a significant cross resistance using abemaciclib in MCF-7pR5 with an IC50 equal to 6.8 vs 0.35 µM and in T47DpR with an IC50 of 10.72 vs 0.5 µM. RNA sequencing, qRT-qPCR and Western blot results demonstrated a dramatic downregulation of the CDK4 inhibitor CDKN2B in both cell lines and we found upregulation of an miR-31, a putative regulator of CDKN2B. This finding was further validated in a biopsy from a patient progressing on CDK4/6 inhibitor therapy. Conclusions: This study provides new relevant information regarding the mechanism of resistance to CDK4/6 inhibitors and suggests potential new markers to follow up patients during the treatment.

Citation Format: Nicoletta Cordani, Luca Mologni, Rocco Piazza, Viola Cogliati, Francesca Pepe, Serena Capici, Camillo Di Bella, Marta Jaconi, Maria Grazia Cerrito, Matteo Villa, Pietro Tettamanti, Guido Cavaletti, Marialuisa Lavitrano, Marina Elena Cazzaniga. Loss of CDKN2B expression as a potential marker of resistance to CDK4/6 inhibitor in Luminal Breast Cancer cells [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr P1-13-21.

Self-Reported Assessment of the Socio-Economic Impact of Anticancer Chemotherapy-Related Neurotoxicity

Chemotherapy-induced neurotoxicity is a well-known complication of several very effective systemic anticancer treatments, mainly presenting as cognitive impairment ("chemo-brain") and peripheral neuropathy. The social and economic effects of long-lasting chemotherapy-induced neurotoxicity on patients' lifestyles and their relationships are under-investigated, and their impact is, therefore, largely unknown. In this study, we used a web-based questionnaire to record the self-reported perception of chemotherapy-induced neurotoxicity on cancer patients' health status, but also on several different aspects of their daily life. From the study results, it emerged that the impact of chemotherapy-induced neurotoxicity on personal, social, and working activities is very high. A similar effect was also observed when the psychological impact is assessed. Moreover, there is evidence suggesting that the management of CIPN is suboptimal; this is partially due to a lack of effective drugs, but also of appropriate advice from healthcare providers. In conclusion, this study provides evidence for the relevance of the impact on the explored aspects of the daily life of cancer patients and spotlights the need for a larger and more structured investigation on these long-term side effects of anticancer chemotherapy.

Paclitaxel, but Not Cisplatin, Affects Satellite Glial Cells in Dorsal Root Ganglia of Rats with Chemotherapy-Induced Peripheral Neurotoxicity

Chemotherapy-induced peripheral neurotoxicity is one of the most common dose-limiting toxicities of several widely used anticancer drugs such as platinum derivatives (cisplatin) and taxanes (paclitaxel). Several molecular mechanisms related to the onset of neurotoxicity have already been proposed, most of them having the sensory neurons of the dorsal root ganglia (DRG) and the peripheral nerve fibers as principal targets. In this study we explore chemotherapy-induced peripheral neurotoxicity beyond the neuronocentric view, investigating the changes induced by paclitaxel (PTX) and cisplatin (CDDP) on satellite glial cells (SGC) in the DRG and their crosstalk. Rats were chronically treated with PTX (10 mg/Kg, 1qwx4) or CDDP (2 mg/Kg 2qwx4) or respective vehicles. Morpho-functional analyses were performed to verify the features of drug-induced peripheral neurotoxicity. Qualitative and quantitative immunohistochemistry, 3D immunofluorescence, immunoblotting, and transmission electron microscopy analyses were also performed to detect alterations in SGCs and their interconnections. We demonstrated that PTX, but not CDDP, produces a strong activation of SGCs in the DRG, by altering their interconnections and their physical contact with sensory neurons. SGCs may act as principal actors in PTX-induced peripheral neurotoxicity, paving the way for the identification of new druggable targets for the treatment and prevention of chemotherapy-induced peripheral neurotoxicity.

K index utility as diagnostic and prognostic biomarker in the assessment of patients with suspected Multiple Sclerosis

The aim of the present study is to evaluate the composite role of k index in the initial assessment of Multiple Sclerosis (MS) patients and to select useful cut-offs exportable in clinical practice. We analysed CSF/serum samples of 140 patients and followed-up the CIS/MS subgroup for 7 years. Our results suggest κ index as a quantitative diagnostic and prognostic biomarker in MS, significantly associated to baseline lesion load and to successive clinical course. We propose k index ≥106 as a prognostic cut-off to select patients at major risk of relapse, potentially influencing initial therapeutic decisions.

Neurological Complications of Conventional and Novel Anticancer Treatments

Various neurological complications, affecting both the central and peripheral nervous system, can frequently be experienced by cancer survivors after exposure to conventional chemotherapy, but also to modern immunotherapy. In this review, we provide an overview of the most well-known adverse events related to chemotherapy, with a focus on chemotherapy induced peripheral neurotoxicity, but we also address some emerging novel clinical entities related to cancer treatment, including chemotherapy-related cognitive impairment and immune-mediated adverse events. Unfortunately, efficacious curative or preventive treatment for all these neurological complications is still lacking. We provide a description of the possible mechanisms involved to drive future drug discovery in this field, both for symptomatic treatment and neuroprotection.

Evaluation of antitumoral effect of Hibiscus sabdariffa extract on human breast cancer cells

BackgroundBreast cancer is the most frequent tumor in women. Natural substances represent an important source of innovative therapeutic solutions, eventually integrating or substituting conventional drugs and chemicals. Hibiscus sabdariffa L. is a plant of the Malvaceae family that has raised interest thanks to its anti-inflammatory, antioxidant and anticancer effects. In this work, we evaluated the antitumoral effects of an enriched fraction of Hibiscus sabdariffa L. extract (HsEF) in two human breast cancer cell lines, MCF-7(ERα +) and MDA-MB-231 (triple negative).

Methods and resultsCell viability was assessed by MTT and Trypan blue assays. HsEF reduced both cell lines viability in a dose and time dependent manner and this effect results irreversible. In MCF-7 cells immunofluorescence experiments, demonstrated that HsEF induced ERα trans-location from nucleus to perinuclear area and in cytoplasmic compartment. qRT-PCR and western blotting high-lighted that HsEF reduced ERα, BRCA1 and caveolin1 gene and protein expression in MCF-7 cells, but not in MDA-MB-231 cells. Moreover, we demonstrated that HsEF reduced proteasome activity, an increased autophagy, impair migration and invasion in both cell lines.

ConclusionsOur data suggest HsEF has an antitumoral effects on both breast tumor cells examined and that ERα involvement could explain the differences observed between the two cell lines.

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Breast cancer conventional treatments have some limitations, such as drug resistance, metastasis and high heterogeneity.

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Natural products and their metabolites represent an alternative and an interesting therapeutic option.

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H. sabdariffa reduce cell viability, cell migration and cell invasion of breast cancer cell lines MCF-7 and MDA-MB-231.

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H. sabdariffa inhibits proteasome and induces autophagy.

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H.sabdariffa induce estrogen receptor downregulation and intracellular de-localization.

Calmangafodipir for Prevention of Oxaliplatin-Induced Peripheral Neuropathy: Two Placebo-Controlled, Randomized Phase 3 Studies (POLAR-A/POLAR-M)

BACKGROUND

Calmangafodipir (CaM, PledOx) demonstrated efficacy in preventing patient-reported chemotherapy-induced peripheral neuropathy (CIPN) in a randomized phase 2 study in patients with metastatic colorectal cancer. The Preventive Treatment of OxaLiplatin Induced peripherAl neuRopathy (POLAR) program aimed to assess efficacy and safety of CaM in the prevention of CIPN in patients treated with oxaliplatin in adjuvant (POLAR-A, ClinicalTrials.gov.NCT04034355) or metastatic (POLAR-M, ClinicalTrials.gov.NCT03654729) settings.

METHODS

Two randomized, placebo-controlled phase 3 trials investigated patient-reported, moderate-to-severe CIPN 9 months after beginning folinic acid, 5-fluorouracil, and oxaliplatin therapy with or without CaM. In POLAR-A, patients with stage III or high-risk stage II colorectal cancer were randomly assigned 1:1 to receive CaM 5 μmol/kg or placebo. In POLAR-M, patients with metastatic colorectal cancer were randomly assigned 1:1:1 to receive CaM 5 μmol/kg, CaM 2 μmol/kg, or placebo.

RESULTS

POLAR-A (n = 301) and POLAR-M (n = 291) were terminated early following unexpected hypersensitivity reactions in CaM-treated patients. In a combined analysis of month 9 CIPN (primary endpoint) data from both trials (CaM 5 μmol/kg, n = 175; placebo, n = 176), 54.3% of patients in the CaM group had moderate-to-severe CIPN compared with 40.3% in the placebo group. The estimated relative risk for moderate-to-severe CIPN at month 9 was 1.37 (95% confidence interval = 1.01 to 1.86; P = .045). A higher proportion of patients experienced serious hypersensitivity reactions across both trials with CaM treatment (3.6%) than with placebo (0.8%).

CONCLUSION

The POLAR clinical studies failed to meet their primary endpoint. These results highlight the challenges of targeting oxidative stress for preventing CIPN in both the adjuvant and metastatic settings.

ESMO Expert Consensus Statements on Cancer Survivorship: promoting high-quality survivorship care and research in Europe

BACKGROUND

The increased number of cancer survivors and the recognition of physical and psychosocial challenges, present from cancer diagnosis through active treatment and beyond, led to the discipline of cancer survivorship.

DESIGN AND METHODS

Herein, we reflected on the different components of survivorship care, existing models and priorities, in order to facilitate the promotion of high-quality European survivorship care and research.

RESULTS

We identified five main components of survivorship care: (i) physical effects of cancer and chronic medical conditions; (ii) psychological effects of cancer; (iii) social, work and financial effects of cancer; (iv) surveillance for recurrences and second cancers; and (v) cancer prevention and overall health and well-being promotion. Survivorship care can be delivered by structured care models including but not limited to shared models integrating primary care and oncology services. The choice of the care model to be implemented has to be adapted to local realities. High-quality care should be expedited by the generation of: (i) focused and shared European recommendations, (ii) creation of tools to facilitate implementation of coordinated care and (iii) survivorship educational programs for health care teams and patients. The research agenda should be defined with the participation of health care providers, researchers, policy makers, patients and caregivers. The following patient-centered survivorship research areas were highlighted: (i) generation of a big data platform to collect long-term real-world data in survivors and healthy controls to (a) understand the resources, needs and preferences of patients with cancer, and (b) understand biological determinants of survivorship issues, and (ii) develop innovative effective interventions focused on the main components of survivorship care.

CONCLUSIONS

The European Society for Medical Oncology (ESMO) can actively contribute in the efforts of the oncology community toward (a) promoting the development of high-quality survivorship care programs, (b) providing educational material and (c) aiding groundbreaking research by reflecting on priorities and by supporting research networking.

From Nature to Synthetic Compounds: Novel 1(N),2,3 Trisubstituted-5-oxopyrrolidines Targeting Multiple Myeloma Cells

The insurgence of drug resistance in treating Multiple Myeloma (MM) still represents a major hamper in finding effective treatments, although over the past decades new classes of drugs, such as proteasome inhibitors and immunomodulatory drugs, have been discovered. Recently, our research team, within a Nature-Aided Drug Discovery project, isolated from Hibiscus Sabdariffa L. calyces the secondary metabolite called Hib-ester which possesses antiproliferative properties against human multiple myeloma RPMI 8226 cells, reduces migration and cell invasion and inhibits proteasome without neurotoxic effects. In the present study, we explored the chemical spaces of the hit compound Hib-ester. We explored the structure-activity relationships (SAR), and we optimized the scaffold through sequentially modifying Hib-ester subunits. Compound screening was performed based on cytotoxicity against the RPMI 8226 cells to assess the potential efficacy toward human MM. The ability of the most effective molecules to inhibit the proteasome was evaluated and the binding mode of the most promising compounds in the proteasome chymotrypsin binding pocket was deciphered through molecular modeling simulations. Compounds 13 and 14 are more potent than Hib-ester, demonstrating that our strategy was suitable for the identification of a novel chemotype for developing possible drug candidates and hopefully widening the drug armamentarium against MM.

HDACi: The Columbus' Egg in Improving Cancer Treatment and Reducing Neurotoxicity?

Histone deacetylases (HDACs) are a group of enzymes that modify gene expression through the lysine acetylation of both histone and non-histone proteins, leading to a broad range of effects on various biological pathways. New insights on this topic broadened the knowledge on their biological activity and even more questions arose from those discoveries. The action of HDACs is versatile in biological pathways and, for this reason, inhibitors of HDACs (HDACis) have been proposed as a way to interfere with HDACs' involvement in tumorigenesis. In 2006, the first HDACi was approved by FDA for the treatment of cutaneous T-cell lymphoma; however, more selective HDACis were recently approved. In this review, we will consider new information on HDACs' expression and their regulation for the treatment of central and peripheral nervous system diseases.

Electrodiagnosis of Guillain-Barre syndrome in the International GBS Outcome Study: Differences in methods and reference values

OBJECTIVE

To describe the heterogeneity of electrodiagnostic (EDx) studies in Guillain-Barré syndrome (GBS) patients collected as part of the International GBS Outcome Study (IGOS).

METHODS

Prospectively collected clinical and EDx data were available in 957 IGOS patients from 115 centers. Only the first EDx study was included in the current analysis.

RESULTS

Median timing of the EDx study was 7 days (interquartile range 4-11) from symptom onset. Methodology varied between centers, countries and regions. Reference values from the responding 103 centers were derived locally in 49%, from publications in 37% and from a combination of these in the remaining 15%. Amplitude measurement in the EDx studies (baseline-to-peak or peak-to-peak) differed from the way this was done in the reference values, in 22% of motor and 39% of sensory conduction. There was marked variability in both motor and sensory reference values, although only a few outliers accounted for this.

CONCLUSIONS

Our study showed extensive variation in the clinical practice of EDx in GBS patients among IGOS centers across the regions.

SIGNIFICANCE

Besides EDx variation in GBS patients participating in IGOS, this diversity is likely to be present in other neuromuscular disorders and centers. This underlines the need for standardization of EDx in future multinational GBS studies.

Frequency and clinical correlates of anti-nerve antibodies in a large population of CIDP patients included in the Italian database

OBJECTIVE

To investigate the frequency and clinical correlates of anti-nerve autoantibodies in an unselected series of Italian patients with chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) METHODS: Sera from 276 CIDP patients fulfilling the EFNS/PNS criteria and included in the Italian CIDP database were examined for the presence of anti-nerve autoantibodies. Results were correlated with the clinical data collected in the database.

RESULTS

Anti-neurofascin155 (NF155) antibodies were found in 9/258 (3.5%) patients, anti-contactin1 (CNTN1) antibodies in 4/258 (1.6%) patients, and anti-contactin-associated protein1 (Caspr1) in 1/197 (0.5%) patients, while none had reactivity to gliomedin or neurofascin 186. Predominance of IgG4 isotype was present in 7of the 9 examined patients. Anti-NF155 patients more frequently had ataxia, tremor, and higher CSF protein levels than antibody-negative patients. Anti-CNTN1 patients more frequently had a GBS-like onset, pain, and ataxia and had more severe motor impairment at enrollment than antibody-negative patients. They more frequently received plasmapheresis, possibly reflecting a less satisfactory response to IVIg or steroids. IgM antibodies against one or more gangliosides were found in 6.5% of the patients (17/260) and were more frequently directed against GM1 (3.9%). They were frequently associated with a progressive course, with a multifocal sensorimotor phenotype and less frequent cranial nerve involvement and ataxia.

CONCLUSIONS

Anti-paranodal and anti-ganglioside antibodies are infrequent in patients with CIDP but are associated with some typical clinical association supporting the hypothesis that CIDP might be a pathogenically heterogeneous syndrome possibly explaining the different clinical presentations.

Making Connections: Mesenchymal Stem Cells Manifold Ways to Interact with Neurons

Mesenchymal Stem Cells (MSCs) are adult multipotent cells able to increase sensory neuron survival: direct co-culture of MSCs with neurons is pivotal to observe a neuronal survival increase. Despite the identification of some mechanisms of action, little is known about how MSCs physically interact with neurons. The aim of this paper was to investigate and characterize the main mechanisms of interaction between MSCs and neurons. Morphological analysis showed the presence of gap junctions and tunneling nanotubes between MSCs and neurons only in direct co-cultures. Using a diffusible dye, we observed a flow from MSCs to neurons and further analysis demonstrated that MSCs donated mitochondria to neurons. Treatment of co-cultures with the gap junction blocker Carbenoxolone decreased neuronal survival, thus demonstrating the importance of gap junctions and, more in general, of cell communication for the MSC positive effect. We also investigated the role of extracellular vesicles; administration of direct co-cultures-derived vesicles was able to increase neuronal survival. In conclusion, our study demonstrates the presence and the importance of multiple routes of communication between MSCs and neurons. Such knowledge will allow a better understanding of the potential of MSCs and how to maximize their positive effect, with the final aim to provide the best protective treatment.

Prospectively Assessing Serum Neurofilament Light Chain Levels As A Biomarker Of Paclitaxel-Induced Peripheral Neurotoxicity In Breast Cancer Patients

Our aim was to assess the significance of measuring serum neurofilament light chain (sNfL) levels as biomarker of paclitaxel-induced peripheral neurotoxicity (PIPN). We longitudinally measured sNfL in breast cancer patients, scheduled to receive the 12-weekly paclitaxel-based regimen. Patients were clinically examined by means of the Total Neuropathy Score-clinical version (TNSc), while sNfL were quantified, using the highly-sensitive Simoa technique, before starting chemotherapy (Baseline), after 2 (week-2) and 3 (week-3) weekly courses, and at the end of chemotherapy (week-12). Among 59 included patients (mean age: 53.1±11.5 years), 33 (56%) developed grade 0-1 and 26 (44%) grade 2-3 PIPN at week-12. A significant longitudinal increase of sNfL levels from baseline to week-12 was determined, whereas patients wth TNSc grade 2-3 PIPN had significantly increased sNfL levels at week-12, compared to those with grade 0-1. ROC analysis defined a value of NfL of >85 pg/mL at week-3 as the best discriminative determination to predict the development of grade 2-3 PIPN at week-12 (sensitivity 46.2%, specificity 84.8%). The logistic binary regression analysis revealed that age >50 years and the cutoff of >85 pg/mL of sNfL levels at week-3 independently predicted the development of grade 2-3 PIPN at week-12 with a sensitivity of 46%, a specificity of 91%, and a positive and negative predictive values of 75% and 67%, respectively. sNfL levels seem to be a valuable biomarker of neuro-axonal injury in PIPN. Early increase of this biomarker after a 3 weekly chemotherapy course can be a predictive marker of final PIPN severity. This article is protected by copyright. All rights reserved.

Rehabilitation, exercise, and related non-pharmacological interventions for chemotherapy-induced peripheral neurotoxicity: Systematic review and evidence-based recommendations

Pharmacological strategies for chemotherapy-induced peripheral neurotoxicity (CIPN) are very limited. We systematically reviewed data on rehabilitation, exercise, physical therapy, and other physical non-pharmacological interventions and offered evidence-based recommendations for the prevention and treatment of CIPN. A literature search using PubMed, Web of Science and CINAHL was conducted from database inception until May 31st, 2021. 2791 records were title-abstract screened, 71 papers were full-text screened, 41 studies were included, 21 on prevention and 20 on treatment of CIPN. Treatment type, cancer type, chemotherapy compounds were heterogeneous, sample size was small (median: N = 34) and intention-to-treat analysis was lacking in 26/41 reports. Because of the methodological issues of included studies, the reviewed evidence should be considered as preliminary. Exercise, endurance, strength, balance, and sensorimotor training have been studied in low-to-moderate quality studies, while the evidence for other treatments is preliminary/inconclusive. We offer recommendation for the design of future trials on CIPN.

Predicting Outcome in Guillain-Barré Syndrome: International Validation of the Modified Erasmus GBS Outcome Score

BACKGROUND AND OBJECTIVES

The clinical course and outcome of the Guillain-Barré syndrome (GBS) are diverse and vary among regions. The modified Erasmus GBS Outcome Score (mEGOS), developed with data from Dutch patients, is a clinical model that predicts the risk of walking inability in patients with GBS. The study objective was to validate the mEGOS in the International GBS Outcome Study (IGOS) cohort and to improve its performance and region specificity.

METHODS

We used prospective data from the first 1,500 patients included in IGOS, aged ≥6 years and unable to walk independently. We evaluated whether the mEGOS at entry and week 1 could predict the inability to walk unaided at 4 and 26 weeks in the full cohort and in regional subgroups, using 2 measures for model performance: (1) discrimination: area under the receiver operating characteristic curve (AUC) and (2) calibration: observed vs predicted probability of being unable to walk independently. To improve the model predictions, we recalibrated the model containing the overall mEGOS score, without changing the individual predictive factors. Finally, we assessed the predictive ability of the individual factors.

RESULTS

For validation of mEGOS at entry, 809 patients were eligible (Europe/North America [n = 677], Asia [n = 76], other [n = 56]), and 671 for validation of mEGOS at week 1 (Europe/North America [n = 563], Asia [n = 65], other [n = 43]). AUC values were >0.7 in all regional subgroups. In the Europe/North America subgroup, observed outcomes were worse than predicted; in Asia, observed outcomes were better than predicted. Recalibration improved model accuracy and enabled the development of a region-specific version for Europe/North America (mEGOS-Eu/NA). Similar to the original mEGOS, severe limb weakness and higher age were the predominant predictors of poor outcome in the IGOS cohort.

DISCUSSION

mEGOS is a validated tool to predict the inability to walk unaided at 4 and 26 weeks in patients with GBS, also in countries outside the Netherlands. We developed a region-specific version of mEGOS for patients from Europe/North America.

CLASSIFICATION OF EVIDENCE

This study provides Class II evidence that the mEGOS accurately predicts the inability to walk unaided at 4 and 26 weeks in patients with GBS.

TRIAL REGISTRATION INFORMATION

NCT01582763.

Systems Pharmacology Modeling Identifies a Novel Treatment Strategy for Bortezomib-Induced Neuropathic Pain

Chemotherapy-induced peripheral neurotoxicity is a common dose-limiting side effect of several cancer chemotherapeutic agents, and no effective therapies exist. Here we constructed a systems pharmacology model of intracellular signaling in peripheral neurons to identify novel drug targets for preventing peripheral neuropathy associated with proteasome inhibitors. Model predictions suggested the combinatorial inhibition of TNFα, NMDA receptors, and reactive oxygen species should prevent proteasome inhibitor-induced neuronal apoptosis. Dexanabinol, an inhibitor of all three targets, partially restored bortezomib-induced reduction of proximal action potential amplitude and distal nerve conduction velocity in vitro and prevented bortezomib-induced mechanical allodynia and thermal hyperalgesia in rats, including a partial recovery of intraepidermal nerve fiber density. Dexanabinol failed to restore bortezomib-induced decreases in electrophysiological endpoints in rats, and it did not compromise bortezomib anti-cancer effects in U266 multiple myeloma cells and a murine xenograft model. Owing to its favorable safety profile in humans and preclinical efficacy, dexanabinol might represent a treatment option for bortezomib-induced neuropathic pain.

Optimal outcome measures for assessing exercise and rehabilitation approaches in chemotherapy-induced peripheral-neurotoxicity: Systematic review and consensus expert opinion

INTRODUCTION

Chemotherapy-induced peripheral neurotoxicity (CIPN) remains a significant toxicity in cancer survivors without preventative strategies or rehabilitation. Exercise and physical activity-based interventions have demonstrated promise in reducing existing CIPN symptoms and potentially preventing toxicity, however there is a significant gap in evidence due to the lack of quality clinical trials and appropriate outcome measures.

AREAS COVERED

We systematically reviewed outcome measures in CIPN exercise and physical rehabilitation studies with expert panel consensus via the Peripheral Nerve Society Toxic Neuropathy Consortium to provide recommendations for future trials. Across 26 studies, 75 outcome measures were identified and grouped into 16 domains within three core areas - measures of manifestations of CIPN (e.g. symptoms/signs), measures of the impact of CIPN and other outcome measures.

EXPERT OPINION

This article provides a conceptual framework for CIPN outcome measures and highlights the need for definition of a core outcome measures set. The authors provide recommendations for CIPN exercise and physical rehabilitation trial design and outcome measure selection. The development of a core outcome measure set will be critical in the search for neuroprotective and treatment approaches to support cancer survivors and to address the gap in the identification of effective rehabilitation and treatment options for CIPN.

The neurophysiological lesson from the Italian CIDP database

INTRODUCTION

Electrophysiological diagnosis of chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) may be challenging. Thus, with the aim ofproviding some practical advice in electrophysiological approach to a patient with suspected CIDP, we analyzed electrophysiological data from 499 patients enrolled inthe Italian CIDP Database.

METHODS

We calculated the rate of each demyelinating feature, the rate of demyelinating features per nerve, the diagnostic rate for upper andlower limb nerves, and, using a ROC curve analysis, the diagnostic accuracy of each couple of nerves and each demyelinating feature, for every CIDP subtype.Moreover, we compared the electrophysiological data of definite and probable CIDP patients with those of possible and not-fulfilling CIDP patients, and by a logisticregression analysis, we estimated the odds ratio (OR) to make an electrophysiological diagnosis of definite or probable CIDP.

RESULTS

The ulnar nerve had the highestrate of demyelinating features and, when tested bilaterally, had the highest diagnostic accuracy except for DADS in which peroneal nerves were the most informative.In possible and not-fulfilling CIDP patients, a lower number of nerves and proximal temporal dispersion (TD) measurements had been performed compared to definiteand probable CIDP patients. Importantly, OR for each tested motor nerve and each TD measurement was 1.59 and 1.33, respectively.

CONCLUSION

Our findingsdemonstrated that the diagnosis of CIDP may be missed due to inadequate or incomplete electrophysiological examination or interpretation. At the same time, thesedata taken together could be useful to draw a thoughtful electrophysiological approach to patients suspected of CIDP.

Exercise and Neuropathy: Systematic Review with Meta-Analysis

INTRODUCTION

Peripheral neuropathies are a prevalent, heterogeneous group of diseases of the peripheral nervous system. Symptoms are often debilitating, difficult to treat, and usually become chronic. Not only do they diminish patients' quality of life, but they can also affect medical therapy and lead to complications. To date, for most conditions there are no evidence-based causal treatment options available. Research has increased considerably since the last review in 2014 regarding the therapeutic potential of exercise interventions for patients with polyneuropathy.

OBJECTIVE

Our objective in this systematic review with meta-analysis was to analyze exercise interventions for neuropathic patients in order to update a systematic review from 2014 and to evaluate the potential benefits of exercise on neuropathies of different origin that can then be translated into practice.

METHODS

Two independent reviewers performed a systematic review with meta-analysis according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). Inclusion criteria according to the PICOS approach were: neuropathic patients, exercise interventions only, an inactive or non-exercising control group, and solely randomized controlled trials with the following outcome parameters: neuropathic symptoms, balance parameters, functional mobility, gait, health-related quality of life, and HbA1c (glycated hemoglobin).

RESULTS

A total of 41 randomized, controlled trials met all inclusion criteria, 20 of which could be included in the quantitative analysis. Study quality varied from moderate to high. Current data further support the hypothesis that exercise is beneficial for neuropathic patients. This is best documented for patients with diabetic peripheral neuropathy (DPN) (27 studies) as well as for chemotherapy-induced peripheral neuropathy (CIPN) (nine studies), while there are only few studies (five) on all other causes of neuropathy. We found standardized mean differences in favor of the exercise group of 0.27-2.00 for static balance, Berg Balance Scale, Timed-up-and-go-test, nerve conduction velocity of peroneal and sural nerve as well as for HbA1c in patients with DPN, and standardized mean differences of 0.43-0.75 for static balance, quality of life, and neuropathy-induced symptoms in patients with CIPN.

CONCLUSION

For DPN, evidence-based recommendations can now be made, suggesting a combination of endurance and sensorimotor training to be most beneficial. For patients with CIPN, sensorimotor training remains the most crucial component. For all other neuropathies, more high-quality research is needed to derive evidence-based recommendations. Overall, it seems that sensorimotor training has great potential to target most neuropathies and combined with endurance training is therefore currently the best treatment option for neuropathies. REGISTRATION NUMBER: (PROSPERO 2019 CRD42019124583)/16.04.2019.

Rigosertib and Cholangiocarcinoma: A Cell Cycle Affair

Rigosertib is multi-kinase inhibitor that could represent an interesting therapeutic option for non-resectable patients with cholangiocarcinoma, a very aggressive hepatic cancer with limited effective treatments. The Western blotting technique was used to evaluate alterations in the expression of proteins involved in the regulation of the cell cycle of cholangiocarcinoma EGI-1 cells. Our results show an increase in EMI1 and Cyclin B protein levels after Rigosertib treatment. Moreover, the phosphorylation of CDK1 is significantly reduced by Rigosertib, while PLK1 expression increased after 24 h of treatment and decreased after 48 h. Finally, we evaluated the role of p53. Its levels increase after Rig treatment, and, as shown in the cell viability experiment with the p53 inhibitor Pifithrin, its activity is necessary for the effects of Rigosertib against the cell viability of EGI-1 cells. In conclusion, we hypothesized the mechanism of the action of Rigosertib against cholangiocarcinoma EGI-1 cells, highlighting the importance of proteins involved in the regulation of cell cycles. The CDK1-Cyclin B complex and p53 play an important role, explaining the Block in the G2/M phase of the cell cycle and the effect on cell viability.

Clinical and preclinical features of eribulin-related peripheral neuropathy

Different microtubule-targeting agents (MTAs) possess distinct modes of action and their clinical use in cancer treatment is often limited by chemotherapy-induced peripheral neurotoxicity (CIPN). Eribulin is a member of the halichondrin class of antineoplastic drugs, which is correlated with a high antimitotic activity against metastatic breast cancer and liposarcoma. Current clinical evidence suggests that eribulin treatment, unlike some of the other MTAs, is associated with a relatively low incidence of severe peripheral neuropathy. This suggests that different MTAs possess unique mechanisms of neuropathologic induction. Animal models reliably reproduced eribulin-related neuropathy providing newer insights in CIPN pathogenesis, and they are highly suitable for in vivo functional, symptomatic and morphological characterizations of eribulin-related CIPN. The purpose of this review is to discuss the most recent literature on eribulin with a focus on both clinical and preclinical data, to explain the molecular events responsible for its favorable neurotoxic profile.

Breast radiotherapy with kilovoltage photons and gold nanoparticles as radiosensitizer: An in vitro study

Purpose

We investigated the dose enhancement and internalization of gold nanoparticles (AuNPs) used as a radiosensitizer agent for rotational radiotherapy of breast cancer using a kilovoltage (kV) X‐ray beam.

Methods

Human breast cancer cells MDA‐MB‐231 were incubated with or without 100 μg/mL (4.87 nM) or 200 μg/mL (9.74 nM) 15 nm AuNPs and irradiated with 100 kV, 190 kV, or 6 MV X‐rays. To assess the toxicity of the AuNPs, we performed a Sulforhodamine B assay. Using atomic absorption spectroscopy, scanning electron microscopy, transmission electron microscopy, and time‐lapse optical microscopy (rate of 2 frames per minute), we carried out a quantitative assessment of the amount of gold internalized by MDA‐MB‐231 cells and a characterization of the static and dynamical aspects of this internalization process.

Results

No effect of AuNPs alone was shown on cell viability. Time‐lapse optical microscopy showed for the first time AuNPs cellular uptake and the dynamics of AuNPs internalization. Electron microscopy demonstrated AuNPs localization in endosomal vesicles, preferentially in the perinuclear region. After irradiation at doses up to 2 Gy, cell survival fraction curves showed increased mortality with AuNPs, with respect to irradiation without AuNPs. The highest effect of radioenhancement by AuNPs (at 9.74 nM AuNPs concentration) was observed at 190 kV showing a dose enhancement factor of 1.33 ± 0.06 (1.34 ± 0.02 at 100 kV), while at 6 MV it was 1.14 ± 0.06.

Conclusions

The observed radio‐sensitization effect is promising for future radio‐enhanced kV radiotherapy of breast cancer and quantitatively in the order of previous observations for 15 nm AuNPs. These results of a significant dose enhancement were obtained at 15 nm AuNPs concentration as low as several nanomolar units, at dose levels typical of a single dose fraction in a radiotherapy session. Dynamical behavior of the 3D spatial distribution of 15 nm AuNPs outside the nucleus of single breast cancer cell was observed, with possible implications for future models of AuNPs sensitization.

Serum neurofilament light chain levels as biomarker of paclitaxel-induced cognitive impairment in patients with breast cancer: a prospective study

OBJECTIVE

To prospectively assess the utility of serum neurofilament light chain (sNfL) levels in identifying the risk to develop chemotherapy-induced cognitive impairment (CICI) in cancer patients. We also examined if sNfL can be identified as an early biomarker of CICI development.

METHODS

We longitudinally measured sNfL levels in 20 female patients with breast cancer, scheduled to receive the 12 weekly paclitaxel-based regimen. An equal number of age-matched female heathy subjects was incuded as control group. CICI was graded by means of the Montreal Cognitive Assessment scale (MOCA); peripheral neurotoxicity (PN) was graded using the neurosensory Common Criteria for Adverse Events (CTCAE)v5.0, while sNfL levels were quantified using a high-sensitive technique (Quanterix, Simoa) before the administration of chemotherapy (T0), after 3 courses (T1), and at the end of chemotherapy (T2).

RESULTS

Pre-treatment sNfL levels were comparable in patients and controls (p = 0.103). At T2, 5/20 patients (mean age 61.4 ± 5.0 years) developed CICI. These 5 patients also had clinically-significant PN. Patients with and without CICI had comparable sNfL values at T2 (p = 0.1). In addition, at T2, sNfL levels did not correlate significantly with MOCA score in CICI patients (p = 0.604). The difference of sNfL levels between T1 and T0 failed to predict independently the occurrence of CICI at T2.

CONCLUSION

Our findings do not support the utility of measuring sNfL levels as a biomarker of CICI. Grade 2-3 PN most strongly confounded our outcomes. Considering the small sample size, which might have prevented the results from being extrapolated, further testing in larger studies is warranted.

Intravenous immunoglobulin treatment for mild Guillain-Barré syndrome: an international observational study

OBJECTIVE

To compare the disease course in patients with mild Guillain-Barré syndrome (GBS) who were treated with intravenous immunoglobulin (IVIg) or supportive care only.

METHODS

We selected patients from the prospective observational International GBS Outcome Study (IGOS) who were able to walk independently at study entry (mild GBS), treated with one IVIg course or supportive care. The primary endpoint was the GBS disability score four weeks after study entry, assessed by multivariable ordinal regression analysis.

RESULTS

Of 188 eligible patients, 148 (79%) were treated with IVIg and 40 (21%) with supportive care. The IVIg group was more disabled at baseline. IVIg treatment was not associated with lower GBS disability scores at 4 weeks (adjusted OR (aOR) 1.62, 95% CI 0.63 to 4.13). Nearly all secondary endpoints showed no benefit from IVIg, although the time to regain full muscle strength was shorter (28 vs 56 days, p=0.03) and reported pain at 26 weeks was lower (n=26/121, 22% vs n=12/30, 40%, p=0.04) in the IVIg treated patients. In the subanalysis with persistent mild GBS in the first 2 weeks, the aOR for a lower GBS disability score at 4 weeks was 2.32 (95% CI 0.76 to 7.13). At 1 year, 40% of all patients had residual symptoms.

CONCLUSION

In patients with mild GBS, one course of IVIg did not improve the overall disease course. The certainty of this conclusion is limited by confounding factors, selection bias and wide confidence limits. Residual symptoms were often present after one year, indicating the need for better treatments in mild GBS.

Cannabinoids: an Effective Treatment for Chemotherapy-Induced Peripheral Neurotoxicity?

Chemotherapy-induced peripheral neurotoxicity (CIPN) is one of the most frequent side effects of antineoplastic treatment, particularly of lung, breast, prostate, gastrointestinal, and germinal cancers, as well as of different forms of leukemia, lymphoma, and multiple myeloma. Currently, no effective therapies are available for CIPN prevention, and symptomatic treatment is frequently ineffective; thus, several clinical trials are addressing this unmet clinical need. Among possible pharmacological treatments of CIPN, modulation of the endocannabinoid system might be particularly promising, especially in those CIPN types where analgesia and neuroinflammation modulation might be beneficial. In fact, several clinical trials are ongoing with the specific aim to better investigate the changes in endocannabinoid levels induced by systemic chemotherapy and the possible role of endocannabinoid system modulation to provide relief from CIPN symptoms, a hypothesis supported by preclinical evidence but never consistently demonstrated in patients. Interestingly, endocannabinoid system modulation might be one of the mechanisms at the basis of the reported efficacy of exercise and physical therapy in CIPN patients. This possible virtuous interplay will be discussed in this review.

Nerve pathology in animal models of neuropathies

To understand the pathology of axonal degeneration and demyelination in peripheral neuropathy, histological investigations in different animal models that mimic some aspects of human peripheral neuropathy are needed. Thus, in the following section of this special issue, the main pathological features of experimental autoimmune neuritis, animal models of chemotherapy-induced peripheral neuropath and of human inherited peripheral neuropathies (IPNs) will be illustrated. When possible, micrographs from animal models and selected human biopsy will be shown side by side.

Prolonged distal motor latency of median nerve does not improve diagnostic accuracy for CIDP

Compression of the median nerve at the carpal tunnel can give demyelinating features and result in distal motor latency (DML) prolongation fulfilling the EFNS/PNS demyelinating criteria for chronic inflammatory demyelinating polyneuropathy (CIDP). Accordingly, being carpal tunnel syndrome (CTS) common in the general population, the EFNS/PNS guidelines recommend excluding the DML of the median nerve when DML prolongation may be consistent with median neuropathy at the wrist from CTS. The main aims of this study were to verify whether the inclusion of DML of the median nerve (when consistent with CTS) could improve electrophysiological diagnostic accuracy for CIDP and if the median nerve at the carpal tunnel was more prone to demyelination. We analyzed electrophysiological data from 499 patients included consecutively into the Italian CIDP Database. According to the EFNS/PNS criteria, 352 patients had a definite, 10 a probable, and 57 a possible diagnosis of CIDP, while 80 were not fulfilling the diagnostic criteria. The inclusion of DML prolongation of median nerve did not improve significantly the diagnostic accuracy for CIDP; overall diagnostic class changed in 6 out of 499 patients (1.2%) and electrodiagnostic class of CIDP changed from not fulfilling to possible in only 2 patients (2.5% of not-fulfilling patients). In conclusion, we can infer that excluding DML prolongation of median nerve does not increase the risk of missing a diagnosis of CIDP thus corroborating the current EFNS/PNS criteria.

Prospective Evaluation of Health Care Provider and Patient Assessments in Chemotherapy-Induced Peripheral Neurotoxicity

BACKGROUND AND OBJECTIVE

There is no agreement on the gold standard for detection and grading of chemotherapy-induced peripheral neurotoxicity (CIPN) in clinical trials. The objective is to perform an observational prospective study to assess and compare patient-based and physician-based methods for detection and grading of CIPN.

METHODS

Consecutive patients, aged 18 years or older, candidates for neurotoxic chemotherapy, were enrolled in the United States, European Union, or Australia. A trained investigator performed physician-based scales (Total Neuropathy Score-clinical [TNSc], used to calculate Total Neuropathy Score-nurse [TNSn]) and supervised the patient-completed questionnaire (Functional Assessment of Cancer Treatment/Gynecologic Oncology Group-Neurotoxicity [FACT/GOG-NTX]). Evaluations were performed before and at the end of chemotherapy. On participants without neuropathy at baseline, we assessed the association between TNSc, TNSn, and FACT/GOG-NTX. Considering a previously established minimal clinically important difference (MCID) for FACT/GOG-NTX, we identified participants with and without a clinically important deterioration according to this scale. Then, we calculated the MCID for TNSc and TNSn as the difference in the mean change score of these scales between the 2 groups.

RESULTS

Data from 254 participants were available: 180 (71%) had normal neurologic status at baseline. At the end of the study, 88% of participants developed any grade of neuropathy. TNSc, TNSn, and FACT/GOG-NTX showed good responsiveness (standardized mean change from baseline to end of chemotherapy >1 for all scales). On the 153 participants without neuropathy at baseline and treated with a known neurotoxic chemotherapy regimen, we verified a moderate correlation in both TNSc and TNSn scores with FACT/GOG-NTX (Spearman correlation index r = 0.6). On the same sample, considering as clinically important a change in the FACT/GOG-NTX score of at least 3.3 points, the MCID was 3.7 for TNSc and 2.8 for the TNSn.

CONCLUSIONS

MCID for TNSc and TNSn were calculated and the TNSn can be considered a reliable alternative objective clinical assessment if a more extended neurologic examination is not possible. The FACT/GOG-NTX score can be reduced to 7 items and these items correlate well with the TNSc and TNSn.

CLASSIFICATION OF EVIDENCE

This study provides Class III evidence that a patient-completed questionnaire and nurse-assessed scale correlate with a physician-assessed scale.

Alterations of gut microbiota composition in post-finasteride patients: a pilot study

PURPOSE

Post-finasteride syndrome (PFS) has been reported in a subset of patients treated with finasteride (an inhibitor of the enzyme 5alpha-reductase) for androgenetic alopecia. These patients showed, despite the suspension of the treatment, a variety of persistent symptoms, like sexual dysfunction and cognitive and psychological disorders, including depression. A growing body of literature highlights the relevance of the gut microbiota-brain axis in human health and disease. For instance, alterations in gut microbiota composition have been reported in patients with major depressive disorder. Therefore, we have here analyzed the gut microbiota composition in PFS patients in comparison with a healthy cohort.

METHODS

Fecal microbiota of 23 PFS patients was analyzed by 16S rRNA gene sequencing and compared with that reported in ten healthy male subjects.

RESULTS

Sexual dysfunction, psychological and cognitive complaints, muscular problems, and physical alterations symptoms were reported in more than half of the PFS patients at the moment of sample collection. The quality sequence check revealed a low library depth for two fecal samples. Therefore, the gut microbiota analyses were conducted on 21 patients. The α-diversity was significantly lower in PFS group, showing a reduction of richness and diversity of gut microbiota structure. Moreover, when visualizing β-diversity, a clustering effect was found in the gut microbiota of a subset of PFS subjects, which was also characterized by a reduction in Faecalibacterium spp. and Ruminococcaceae UCG-005, while Alloprevotella and Odoribacter spp were increased compared to healthy control.

CONCLUSION

Gut microbiota population is altered in PFS patients, suggesting that it might represent a diagnostic marker and a possible therapeutic target for this syndrome.