Neurological adverse effects caused by cytotoxic and targeted therapies

Most Common Symptomatic Adverse Reactions of Cancer Treatments From US Drug Labels (2015-2021) to Inform Selection of Patient-Reported Outcomes

OBJECTIVES

Incorporating patient-reported outcomes (PROs) to assess symptomatic adverse events (AEs) in cancer clinical trials (CTs) is important to characterize treatment tolerability. Cancer therapies approved over the past decade have expanded the types of expected toxicities. To inform future symptomatic AE PRO item selection, we identified the most common symptomatic adverse reactions from recently approved products.

METHODS

We reviewed approvals from 2015 to 2021 for lung, breast, and hematologic cancer indications. Using United States Prescribing Information safety data, we recorded symptomatic adverse reactions reported in ≥20% of patients in the experimental arm of CTs supporting approvals. We calculated the proportion of arms reporting each symptomatic adverse reaction.

RESULTS

In total, 130 experimental arms were included (lung = 30, breast = 10, hematologic = 90). For all cancer types, fatigue and diarrhea were reported in >50% of the arms. Nausea was reported in ≥50% of the arms for all except lung. Vomiting, decreased appetite, and alopecia, were reported in ≥50% of breast cancer arms. Rash, musculoskeletal pain, and cough were reported in >50% of leukemia/lymphoma arms. Cough was common (50%) in multiple myeloma arms.

CONCLUSIONS

Heterogeneity in symptomatic adverse reactions across CTs supports the use of item libraries when building a PRO strategy to assess tolerability. Fatigue, diarrhea, and nausea were the most frequent symptomatic adverse reactions reported in contemporary cancer CTs and could provide a starting point when selecting PRO symptomatic AE items. Additional symptomatic AE PRO items should be selected based on the mechanism of action, early clinical data, published literature, and patient and clinician input.

Incidence and Clinical Presentation of Severe Neurotoxicity from Nelarabine in Patients with T-Cell Acute Lymphoblastic Leukemia

BACKGROUND

Nelarabine is a purine analog with demonstrated efficacy in the treatment of T-cell Lymphoblastic Leukemia and Lymphoma (T-ALL/LBL). Despite its efficacy and excellent blood-brain barrier penetration, it has a significant side effect profile which is namely concerning for neurotoxicity. Reported neurotoxicity has varied from mild peripheral neuropathy to debilitating grade 4 neurologic complications including Guillain-Barre like syndrome and myelopathy.

PATIENTS AND METHODS

We conducted a single centered, retrospective case series to study patients who developed severe neurotoxicity after receiving nelarabine as part of T-ALL treatment. One hundred thirty-five patients were identified. Thirteen patients were reviewed for severe neurotoxicity (defined as ≥grade 3), and of those five patients were deemed to have neurotoxicity secondary to nelarabine exposure.

RESULTS

Five patients (4%) developed severe neurotoxicity as manifested by Guillain-Barre like syndrome or myelopathy within a timeframe of eight to fifty-eight days from last nelarabine dose. Upon diagnosis, patients received formal neurologic evaluation by our neuro-oncology specialists including imaging, cerebrospinal fluid testing, and electromyography. Patients were treated with IVIG, and steroids upon diagnosis, but the majority of neuro-deficits were irreversible.

CONCLUSION

Our study shows that nelarabine is generally well-tolerated, and the incidence of severe neurotoxicity is rare. Given the potential risk of severe neurotoxicity, we propose capped dose of nelarabine 1000 mg/day, neurological assessment before subsequent dosing, and avoidance of simultaneous IT therapy during nelarabine administration.

Advances in Anti-Cancer Drug Development: Metformin as Anti-Angiogenic Supplemental Treatment for Glioblastoma

According to the WHO 2016 classification, glioblastoma is the most prevalent primary tumor in the adult central nervous system (CNS) and is categorized as grade IV. With an average lifespan of about 15 months from diagnosis, glioblastoma has a poor prognosis and presents a significant treatment challenge. Aberrant angiogenesis, which promotes tumor neovascularization and is a prospective target for molecular target treatment, is one of its unique and aggressive characteristics. Recently, the existence of glioma stem cells (GSCs) within the tumor, which are tolerant to chemotherapy and radiation, has been linked to the highly aggressive form of glioblastoma. Anti-angiogenic medications have not significantly improved overall survival (OS), despite various preclinical investigations and clinical trials demonstrating encouraging results. This suggests the need to discover new treatment options. Glioblastoma is one of the numerous cancers for which metformin, an anti-hyperglycemic medication belonging to the Biguanides family, is used as first-line therapy for type 2 diabetes mellitus (T2DM), and it has shown both in vitro and in vivo anti-tumoral activity. Based on these findings, the medication has been repurposed, which has shown the inhibition of many oncopromoter mechanisms and, as a result, identified the molecular pathways involved. Metformin inhibits cancer cell growth by blocking the LKB1/AMPK/mTOR/S6K1 pathway, leading to selective cell death in GSCs and inhibiting the proliferation of CD133+ cells. It has minimal impact on differentiated glioblastoma cells and normal human stem cells. The systematic retrieval of information was performed on PubMed. A total of 106 articles were found in a search on metformin for glioblastoma. Out of these six articles were Meta-analyses, Randomized Controlled Trials, clinical trials, and Systematic Reviews. The rest were Literature review articles. These articles were from the years 2011 to 2024. Appropriate studies were isolated, and important information from each of them was understood and entered into a database from which the information was used in this article. The clinical trials on metformin use in the treatment of glioblastoma were searched on clinicaltrials.gov. In this article, we examine and evaluate metformin's possible anti-tumoral effects on glioblastoma, determining whether or not it may appropriately function as an anti-angiogenic substance and be safely added to the treatment and management of glioblastoma patients.

Phyto-pharmacological evaluation and characterization of the methanolic extract of the Baccaurea motleyana Müll. Arg. seed: promising insights into its therapeutic uses

Introduction: Plants and their extracts have been integral to the development of medicinal treatments throughout history, offering a vast array of compounds for innovative therapies. Baccaurea motleyana Müll. Arg., commonly known as Rambai, is an evergreen tree with economic importance in the Old-World Tropics. Method: The study investigates its phytochemical composition through Gas Chromatography-Mass Spectrometry (GC-MS) and evaluates its pharmacological properties, including antidiabetic, antidiarrheal, antimicrobial, and antidepressant effects. Result and Discussion: The GC-MS analysis revealed 15 bioactive compounds in the methanol extract, with Phenol, 3,5-bis(1,1-dimethylethyl)-, Methyl stearate, and Hexadecanoic acid, methyl ester being the predominant ones. The cytotoxicity assay demonstrated significant activity in the ethyl acetate fraction. Antimicrobial assays indicated mild to moderate antibacterial activity. In vivo studies on mice revealed significant hypoglycemic, antidiarrheal, and antidepressant properties. Molecular docking studies against EGFR, DHFR, GLUT-3, KOR, and MOA identified promising compounds with potential therapeutic effects. The identified compounds exhibited favorable ADME/T properties, emphasizing their potential for drug development. The study underscores the promising therapeutic potential of Baccaurea motleyana, showcasing its diverse bioactive compounds with significant medicinal properties. Conclusion: These findings lay the groundwork for future research, emphasizing the exploration of B. motleyana as a source of natural remedies for addressing prevalent health conditions.

Exosomes: special nano-therapeutic carrier for cancers, overview on anticancer drugs

Chemotherapy drugs are the first line of cancer treatment, but problems such as low intratumoral delivery, poor bioavailability, and off-site toxicity must be addressed. Cancer-specific drug delivery techniques could improve the therapeutic outcome in terms of patient survival. The current study investigated the loading of chemotherapy drugs loaded into exosomes for cancer treatment. Exosomes are the smallest extracellular vesicles found in body fluids and can be used to transfer information by moving biomolecules from cell to cell. This makes them useful as carriers. As the membranes of these nanoparticles are similar to cell membranes, they can be easily transported to carry different components. As most chemotherapy drugs are not easily soluble in liquid, loading them into exosomes can be a suitable solution to this problem. This cancer treatment could avert the injection of high doses of drugs and provide a more appropriate release mechanism.

Imaging Findings in Children Presenting with CNS Nelarabine Toxicity

Nelarabine is a nucleoside analog critical for the treatment of patients with T-cell acute lymphoblastic leukemia/lymphoma. However, clinical peripheral and central neurologic adverse events associated with nelarabine administration have been reported. Neuroimaging of brain neurotoxicity has only been described in very few reports in pediatric patients so far. Six children with diagnosed T-cell acute lymphoblastic leukemia who clinically experienced possible, probable, or definite nelarabine-induced toxicity and underwent spine and/or brain MR imaging were reviewed. Neuroimaging findings showed a mixture of patterns including features of acute toxic leukoencephalopathy (seen in 6 cases), posterior reversible encephalopathy syndrome (2 cases), involvement of deep gray structures (1 case) and brainstem (2 cases), cranial and spinal neuropathy (2 cases each), and myelopathy (2 cases). Even though neuroimaging findings are nonspecific, the goal of this article was to alert the pediatric neuroradiologists, radiologists, and clinicians about the possibility of nelarabine-induced neurotoxicity and its broad neuroimaging spectrum.

Intravitreal Carboplatin as Salvage Treatment for Progressive Vitreous Disease in Retinoblastoma: a Phase I Clinical Trial

PURPOSE

To determine the safety and toxicity profile of intravitreal carboplatin as salvage treatment for retinoblastoma with vitreous disease.

DESIGN

Single-institution, interventional prospective clinical trial.

PARTICIPANTS

Patients with progressive or recurrent vitreous seeds after completion of primary treatment for intraocular retinoblastoma.

METHODS

Eligible eyes received an intravitreal injection of carboplatin every 14 to 21 days with simultaneous focal therapy (laser, thermotherapy, and brachytherapy) provided at the discretion of the ocular oncologist. The evaluation with examination under anesthesia, ultrasound biomicroscopy, and electroretinography (ERG) were performed before each injection to assess for tumor response and drug-related toxicity. A serious adverse event resulted in dose recalculation and ultimately early closure of the study.

MAIN OUTCOME MEASURES

Regression pattern of vitreous disease and incidence of dose-limiting toxicities.

RESULTS

Four patients were enrolled at an initial dose of 0.3 mg. Complete regression of vitreous seeds was noted in all patients after 5, 2, 2, and 1 injections (respectively). Two patients developed recurrent vitreous disease at 3 and 25 months after complete regression and ultimately required enucleation. A serious adverse event occurred in 1 patient who developed acute vision loss with extinguished ERG response 72 hours after the second injection; ultimately, this eye developed a cataract and required enucleation. After temporary suspension and dose modification, 3 patients were enrolled at an injection dose of 3 μg and treated with a total of 5, 2, and 1 injections, respectively. Complete regression of vitreous disease was not achieved in any patient though ERG amplitudes remained stable. After removal from protocol, all 3 patients had a complete response to intravitreal melphalan. Concern for dose escalation and further toxicity in the setting of an effective and safe alternative (melphalan) led to the termination of the study.

CONCLUSIONS

Intravitreal carboplatin may be effective in treating progressive vitreous seeding at higher doses, but permanent retinal toxicity was observed. Other alternative agents should be considered.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found after the references.

Role of inflammation and oxidative stress in chemotherapy-induced neurotoxicity

Chemotherapeutic agents may adversely affect the nervous system, including the neural precursor cells as well as the white matter. Although the mechanisms are not completely understood, several hypotheses connecting inflammation and oxidative stress with neurotoxicity are now emerging. The proposed mechanisms differ depending on the class of drug. For example, toxicity due to cisplatin occurs due to activation of nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), which alters hippocampal long-term potentiation. Free radical injury is also involved in the cisplatin-mediated neurotoxicity as dysregulation of nuclear factor erythroid 2-related factor 2 (Nrf2) has been seen which protects against the free radical injury by regulating glutathione S-transferases and hemeoxygenase-1 (HO-1). Thus, correcting the imbalance between NF-κB and Nrf2/HO-1 pathways may alleviate cisplatin-induced neurotoxicity. With newer agents like bortezomib, peripheral neuropathy occurs due to up-regulation of TNF-α and IL-6 in the sensory neurons. Superoxide dismutase dysregulation is also involved in bortezomib-induced neuropathy. This article reviews the available literature on inflammation and oxidative stress in neurotoxicity caused by various classes of chemotherapeutic agents. It covers the conventional medicines like platinum compounds, vinca alkaloids, and methotrexate, as well as the newer therapeutic agents like immunomodulators and immune checkpoint inhibitors. A better understanding of the pathophysiology will lead to further advancement in strategies for management of chemotherapy-induced neurotoxicity.

Mid-term treatment-related cognitive sequelae in glioma patients

Purpose

Cognitive functioning represents an essential determinant of quality of life. Since significant advances in neuro-oncological treatment have led to prolonged survival it is important to reliably identify possible treatment-related neurocognitive dysfunction in brain tumor patients. Therefore, the present study specifically evaluates the effects of standard treatment modalities on neurocognitive functions in glioma patients within two years after surgery.

Methods

Eighty-six patients with World Health Organization (WHO) grade 1–4 gliomas were treated between 2004 and 2012 and prospectively followed within the German Glioma Network. They received serial neuropsychological assessment of attention, memory and executive functions using the computer-based test battery NeuroCog FX. As the primary outcome the extent of change in cognitive performance over time was compared between patients who received radiotherapy, chemotherapy or combined radio-chemotherapy and patients without any adjuvant therapy. Additionally, the effect of irradiation and chemotherapy was assessed in subgroup analyses. Furthermore, the potential impact of the extent of tumor resection and histopathological characteristics on cognitive functioning were referred to as secondary outcomes.

Results

After a median of 16.8 (range 5.9–31.1) months between post-surgery baseline neuropsychological assessment and follow-up assessment, all treatment groups showed numerical and often even statistically significant improvement in all cognitive domains. The extent of change in cognitive functioning showed no difference between treatment groups. Concerning figural memory only, irradiated patients showed less improvement than non-irradiated patients (p = 0.029, η² = 0.06). Resected patients, yet not patients with biopsy, showed improvement in all cognitive domains. Compared to patients with astrocytomas, patients with oligodendrogliomas revealed a greater potential to improve in attentional and executive functions. However, the heterogeneity of the patient group and the potentially selected cohort may confound results.

Conclusion

Within a two-year post-surgery interval, radiotherapy, chemotherapy or their combination as standard treatment did not have a detrimental effect on cognitive functions in WHO grade 1–4 glioma patients. Cognitive performance in patients with adjuvant treatment was comparable to that of patients without.

Supplementary Information

The online version contains supplementary material available at 10.1007/s11060-022-04044-1.

Selective delivery of clinically approved tubulin binding agents through covalent conjugation to an active targeting moiety

Abstract:

The efficacy and tolerability of tubulin binding agents are hampered by their low specificity for cancer cells, like most clinically used anticancer agents. To improve specificity, tubulin binding agents have been covalently conjugated to agents which target cancer cells to give actively targeted drug conjugates. These conjugates are designed to increase uptake of the drug by cancer cells, while having limited uptake by normal cells thereby improving efficacy and tolerability. Approaches used include attachment to small molecules, polysaccharides, peptides, proteins and antibodies that exploit the overexpression of receptors for these substances. Antibody targeted strategies have been the most successful to date with six such examples having gained clinical approval. Many other conjugate types, especially those targeting the folate receptor, have shown promising efficacy and toxicity profiles in pre-clinical models and in early-stage clinical studies. Presented herein is a discussion of the success or otherwise of the recent strategies used to form these actively targeted conjugates.

Peripheral Nervous System Involvement in Non-Primary Pediatric Cancer: From Neurotoxicity to Possible Etiologies

Peripheral neuropathy is a well described complication in children with cancer. Oncologists are generally well aware of the toxicity of the main agents, but fear the side effects of new drugs. As chemotherapeutic agents have been correlated with the activation of the immune system such as in Chemotherapy Induced Peripheral Neuropathy (CIPN), an abnormal response can lead to Autoimmune Peripheral Neuropathy (APN). Although less frequent but more severe, Radiation Induced Peripheral Neuropathy may be related to irreversible peripheral nervous system (PNS). Pediatric cancer patients also have a higher risk of entering a Pediatric Intensive Care Unit for complications related to therapy and disease. Injury to peripheral nerves is cumulative, and frequently, the additional stress of a malignancy and its therapy can unmask a subclinical neuropathy. Emerging risk factors for CIPN include treatment factors such as dose, duration and concurrent medication along with patient factors, namely age and inherited susceptibilities. The recent identification of individual genetic variations has advanced the understanding of physiopathological mechanisms and may direct future treatment approaches. More research is needed on pharmacological agents for the prevention or treatment of the condition as well as rehabilitation interventions, in order to allow for the simultaneous delivery of optimal cancer therapy and the mitigation of toxicity associated with pain and functional impairment. The aim of this paper is to review literature data regarding PNS complications in non-primary pediatric cancer.

Anticancer Drugs and the Nervous System

PURPOSE OF REVIEW

This article reviews the clinical features, prognosis, and treatment of neurotoxicity from anticancer drugs, including conventional cytotoxic chemotherapy, biologics, and targeted therapies, with a focus on the newer immunotherapies (immune checkpoint inhibitors and chimeric antigen receptor T cells).

RECENT FINDINGS

Whereas neurologic complications from traditional chemotherapy are widely recognized, newer cancer therapies, in particular immunotherapies, have unique and distinct patterns of neurologic adverse effects. Anticancer drugs may cause central or peripheral nervous system complications. Neurologic complications of therapy are being seen with increasing frequency as patients with cancer are living longer and receiving multiple courses of anticancer regimens, with novel agents, combinations, and longer duration. Neurologists must know how to recognize treatment-related neurologic toxicity since discontinuation of the offending agent or dose adjustment may prevent further or permanent neurologic injury. It is also imperative to differentiate neurologic complications of therapy from cancer progression into the nervous system and from comorbid neurologic disorders that do not require treatment dose reduction or discontinuation.

SUMMARY

Neurotoxicity from cancer therapy is common, with effects seen on both the central and peripheral nervous systems. Immune checkpoint inhibitor therapy and chimeric antigen receptor T-cell therapy are new cancer treatments with distinct patterns of neurologic complications. Early recognition and appropriate management are essential to help prevent further neurologic injury and optimize oncologic management.

Electronic von Frey as an objective assessment tool for oxaliplatin-induced peripheral neuropathy: A prospective longitudinal study

OBJECTIVE

There is wide discrepancy on how to perform clinical assessment of oxaliplatin-induced peripheral neuropathy. In this scenario, the Electronic von Frey (EVF), which evaluates pain objectively based upon mechanical pain thresholds (MPTs), may be a valuable tool. The present study aims to quantify hyperalgesia in the hands and feet of patients treated with oxaliplatin and to propose a novel method to classify the degree of neurotoxicity using EVF-derived measures as cut-off points.

METHODS

This is a prospective cohort study including 46 patients treated for colorectal cancer with the FLOX regimen. Before each oxaliplatin administration, patients were evaluated with the Acute and Chronic Neuropathy Questionnaire, Oxaliplatin-Specific Neurotoxicity Scale and National Cancer Institute Common Terminology Criteria for Adverse Events scale. Also, objective pain assessment with the EVF was performed.

RESULTS

For both upper and lower extremities, EVF was shown to correlate well with patients' symptoms and functional impairment, as assessed by subjective scales. Also, when cut-off MPT variations were determined for diagnosis of neurotoxicity grade 2 or 3, the method showed good sensitivity and specificity.

CONCLUSION

Electronic von Frey is a noninvasive and easy-to-perform objective method with potential to supplement the current assessment tools for oxaliplatin-induced peripheral neuropathy, which are mostly subjective.

Neurological complications of pediatric cancer

Both the onset of various malignancies as well as the treatment of cancer can lead to neurologic symptoms which can be difficult to diagnose. In this review, we highlight the varied ways in which neurologic sequelae of cancer and its treatment manifest in children. Initial neurologic presentation may be secondary to mass effect or to immune-mediated paraneoplastic syndromes. Treatment effects on the nervous system may arise from surgery, chemotherapy, radiation, or bone marrow transplantation. In addition, the rapidly expanding field of immunotherapies for cancer has generated numerous new approaches to eradicating cancer including monoclonal antibodies, checkpoint inhibitors, and chimeric antigen receptor T cells (CAR-T cells), which have neurologic side effects mediated by immune responses that are also being recognized. Here we review common consult questions to the neurologist and our general approach to these scenarios including altered mental status, headaches, seizures, and sensorimotor complaints, considering the multifactorial nature of each.

Neurotoxicity of antineoplastic drugs: Mechanisms, susceptibility, and neuroprotective strategies

This review summarizes the adverse effects on the central and/or peripheral nervous systems that may occur in response to antineoplastic drugs. In particular, we describe the neurotoxic side effects of the most commonly used drugs, such as platinum compounds, doxorubicin, ifosfamide, 5-fluorouracil, vinca alkaloids, taxanes, methotrexate, bortezomib and thalidomide. Neurotoxicity may result from direct action of compounds on the nervous system or from metabolic alterations produced indirectly by these drugs, and either the central nervous system or the peripheral nervous system, or both, may be affected. The incidence and severity of neurotoxicity are principally related to the dose, to the duration of treatment, and to the dose intensity, though other factors, such as age, concurrent pathologies, and genetic predisposition may enhance the occurrence of side effects. To avoid or reduce the onset and severity of these neurotoxic effects, the use of neuroprotective compounds and/or strategies may be helpful, thereby enhancing the therapeutic effectiveness of antineoplastic drug.

FLOX (5-fluorouracil + leucovorin + oxaliplatin) chemotherapy for colorectal cancer leads to long-term orofacial neurotoxicity: a STROBE-guided longitudinal prospective study

BACKGROUND

Colorectal carcinoma (CRC) is widely treated by chemotherapy based on an intensely neurotoxic drug: oxaliplatin (OXL). We objective to evaluate prospectively the orofacial neurotoxicity during FLOX (fluorouracil + leucovorin + OXL) chemotherapy.

METHODS

So, 46 patients with CRC were prospectively evaluated during FLOX chemotherapy by 3 cycles (C) of 6 weeks (W) each. We weekly applied the orofacial section of the Acute and Chronic Neuropathy Questionnaire of Common Toxicity Criteria for Adverse Events of the National Cancer Institute of the United States of America (Oxaliplatin-specific neurotoxicity scale). Patients were asked the following concerning the severity (scores 0-5) of orofacial symptoms: jaw pain, eyelids drooping, throat discomfort, ear pain, tingling in mouth, difficulty with speech, burning or discomfort of the eyes, loss of any vision, feeling shock/pain down back and problems breathing. We summed the scores (0-50) and evaluated the clinicopathological data. Friedman/Dunn, Chi square and multinomial regression logistic tests were used (SPSS 20.0, p < 0.05).

RESULTS

There was a significant increase in sum of orofacial neurotoxicity from baseline to C1.W3, C2.W1 and C3.W5 (p < 0.001) due increase in scores of jaw pain (p < 0.001), eyelids drooping (p = 0.034), throat discomfort (p < 0.001), ear pain (p = 0.034), tingling in mouth (p = 0.015), burning/discomfort of your eyes (p < 0.001), loss of any vision (p < 0.001), feeling shock/pain down back (p < 0.001), problems with breathing (p = 0.045), but not difficulty with speech (p = 0.087). Women (p = 0.021) and young patients (p = 0.027) had significant higher prevalence of orofacial neurotoxicity.

CONCLUSIONS

FLOX-related orofacial neurotoxicity begins acutely and remains long term with increased incidence in women and younger patients.

Thymoquinone-chemotherapeutic combinations: new regimen to combat cancer and cancer stem cells

Cancer is a worldwide disease that causes millions of cases of mortality and morbidity. The major problem associated with the cancer is its resistance to conventional therapy and a high relapse rate. The use of chemotherapy to treat cancer began at the start of the twentieth century with attempts to control cancer. In time advance, many cancer chemotherapeutic agents have been developed for cancer treatment with different mechanisms of action including the alkylating agents, antimetabolites, antimicrotubule, topoisomerase inhibitors, and cytotoxic antibiotics, all of which have toxic effects toward normal cells in the body. Here, we reviewed chemotherapeutics' anticancer role potentiation and safety by thymoquinone (TQ) alone or in combination with the most common therapeutic drugs. Our search was done through PubMed, Science Direct, Springer Link, Taylor & Francis Online, Wiley Online Library, Nature publication group, SAGE Journals, and Web of Science databases. We recognized that TQ-chemotherapeutics combination increased chemo-modulation to the anticancer effect of different chemotherapeutics and protected the normal body cells from the toxic injuries that are induced by chemotherapeutics based on its antioxidant power. Moreover, the current study investigates the possible combinatory effect of TQ and chemotherapeutics to control cancer stem cells through molecular docking targeting of wingless/integrated (Wnt) and Hedgehog (Hh). We found that TQ modulates the Wnt and Hh pathways, by binding with tankyrase-2 and smoothened 7TM receptor, respectively, more efficiently than most chemotherapeutics drugs, while methotrexate showed high-binding affinity compared with TQ. Therefore, we encourage researchers to investigate the chemo-modulatory potential and protective effects of TQ in combination with chemotherapeutics for either cancer or cancer stem cell treatment.

Prevention of chemotherapy-induced peripheral neuropathy: A review of recent findings

Chemotherapy-induced peripheral neuropathy (CIPN) is an adverse effect of chemotherapy that is frequently experienced by patients receiving treatment for cancer. CIPN is caused by many of the most commonly used chemotherapeutic agents, including taxanes, vinca alkaloids, and bortezomib. Pain and sensory abnormalities may persist for months, or even years after the cessation of chemotherapy. The management of CIPN is a significant challenge, as it is not possible to predict which patients will develop symptoms, the timing for the appearance of symptoms can develop anytime during the chemotherapy course, there are no early indications that warrant a reduction in the dosage to halt CIPN progression, and there are no drugs approved to prevent or alleviate CIPN. This review focuses on the etiology of CIPN and will highlight the various approaches developed for prevention and treatment. The goal is to guide studies to identify, test, and standardize approaches for managing CIPN.

Model-based clustering for identifying disease-associated SNPs in case-control genome-wide association studies

Genome-wide association studies (GWASs) aim to detect genetic risk factors for complex human diseases by identifying disease-associated single-nucleotide polymorphisms (SNPs). The traditional SNP-wise approach along with multiple testing adjustment is over-conservative and lack of power in many GWASs. In this article, we proposed a model-based clustering method that transforms the challenging high-dimension-small-sample-size problem to low-dimension-large-sample-size problem and borrows information across SNPs by grouping SNPs into three clusters. We pre-specify the patterns of clusters by minor allele frequencies of SNPs between cases and controls, and enforce the patterns with prior distributions. In the simulation studies our proposed novel model outperforms traditional SNP-wise approach by showing better controls of false discovery rate (FDR) and higher sensitivity. We re-analyzed two real studies to identifying SNPs associated with severe bortezomib-induced peripheral neuropathy (BiPN) in patients with multiple myeloma (MM). The original analysis in the literature failed to identify SNPs after FDR adjustment. Our proposed method not only detected the reported SNPs after FDR adjustment but also discovered a novel BiPN-associated SNP rs4351714 that has been reported to be related to MM in another study.

Combination of Whole-Brain Radiotherapy with Epidermal Growth Factor Receptor Tyrosine Kinase Inhibitors Improves Overall Survival in EGFR-Mutated Non-Small Cell Lung Cancer Patients with Brain Metastases

Brain metastases (BM) cause morbidity and mortality in patients with non-small cell lung cancer (NSCLC). The use of upfront epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) and withholding of whole-brain radiation therapy (WBRT) is controversial. We aim to investigate the impact of WBRT on overall survival (OS). After screening 1384 patients, a total of 141 EGFR-mutated patients with NSCLC and BM were enrolled. All patients received EGFR-TKIs between 2011 and 2015. Ninety-four patients (66.7 %) were treated with WBRT (TKI + WBRT group). With a median follow-up of 20.3 months (95% confidence interval (CI), 16.9-23.7), the median OS after the diagnosis of BM was 14.3 months (95% CI, 9.5 to 18.3) in the TKI + WBRT group and 2.3 months (95% CI, 2 to 2.6) in the TKI alone group. On multivariate analysis, WBRT (p < 0.001), female, surgery to primary lung tumor, and surgery to BM were associated with improved OS. The 1-year OS rate was longer in the TKI+WBRT group than that in the TKI alone group (81.9% vs 59.6%, p = 0.002). In conclusion, this is the first study to demonstrate the negative survival impact from the omission of WBRT in patients with EGFR-mutant NSCLC.

Involvement of Endothelin Receptors in Peripheral Sensory Neuropathy Induced by Oxaliplatin in Mice

The aim of this study was to evaluate the participation of the endothelin ET_A and ET_B receptors and the effects of bosentan in oxaliplatin-induced peripheral sensory neuropathy (OIN) in mice. Adult male Swiss mice received 1 mg/kg of oxaliplatin intravenously, twice a week for 5 weeks. Dorsal root ganglia (DRG) and spinal cords were removed for evaluation of the endothelin ET_A and ET_B receptor expression. Afterwards, selective (BQ-123 and BQ-788; 10 nmol in 30 μL, intraplantarly) and non-selective (bosentan, 100 mg/kg, orally) antagonists were administered in order to evaluate the involvement of the endothelin receptors in OIN. Mechanical and thermal nociception tests were performed once a week for 56 days. Oxaliplatin induced mechanical and thermal hypersensitivity and increased the endothelin ET_A receptor expression in both the DRG and spinal cord (P < 0.05). Endothelin ET_B receptor expression was increased in the DRG (P < 0.05) but not in the spinal cord. Both endothelin ET_A and ET_B receptor selective antagonists partially prevented mechanical hyperalgesia in mice with OIN (P < 0.05). Moreover, bosentan prevented mechanical and thermal hypersensitivity in oxaliplatin-treated mice (P < 0.05). In conclusion, both endothelin ET_A and ET_B receptors seem to be involved in the OIN in mice and they should be considered possible targets for the management of this clinical feature.

CYT997(Lexibulin) induces apoptosis and autophagy through the activation of mutually reinforced ER stress and ROS in osteosarcoma

Background

Osteosarcoma (OS) is a common malignant cancer in children and adolescents and has a cure rate that has not improved in the last two decades. CYT997 (lexibulin) is a novel potent microtubule-targeting agent with various anticancer activities, such as proliferation inhibition, vascular disruption, and cell cycle arrest and apoptosis induction, in multiple cancers. However, the direct cytotoxic mechanisms of CYT997 have not yet been fully characterized.

Methods

We evaluated apoptosis and autophagy in human osteosarcomas after treatment with CYT997 and investigated the underlying mechanisms. To explore relationships, we used the reactive oxygen species (ROS) scavenger N-acetyl cysteine (NAC), PERK inhibitor GSK2606414, ERO1 inhibitor EN460 and mitochondrial targeted protection peptide elamipretide. BALB/c-nu mice were inoculated with 143B tumor cells to investigate the in vivo effect of CYT997.

Results

We explored the efficacy and mechanism of CYT997 in osteosarcoma (OS) in vitro and in vivo and demonstrated that CYT997 potently suppresses cell viability and induces apoptosis and autophagy. CYT997 triggered production of ROS and exerted lethal effects via endoplasmic reticulum (ER) stress in OS cells. NAC attenuated these effects. The PERK inhibitor GSK2606414, which can block the ER stress pathway, reduced ROS production and enhanced cell viability. Moreover, activation of ERO1 in the ER stress pathway was responsible for inducing ROS production. ROS produced by the mitochondrial pathway also aggravate ER stress. Protection of mitochondria can reduce apoptosis and autophagy. Finally, CYT997 prominently reduced tumor growth in vivo.

Conclusions

This study suggests that CYT997 induces apoptosis and autophagy in OS cells by triggering mutually enhanced ER stress and ROS and may thus be a promising agent against OS.

Electronic supplementary material

The online version of this article (10.1186/s13046-019-1047-9) contains supplementary material, which is available to authorized users.

Progesterone Is More Effective Than Dexamethasone in Prolonging Overall Survival and Preserving Neurologic Function in Experimental Animals with Orthotopic Glioblastoma Allografts

OBJECTIVE

Dexamethasone (DEXA) has been widely used in the management of peritumoral brain edema. DEXA, however, has many systemic side effects and can interact negatively with glioma therapy. Progesterone (PROG), however, is a well-tolerated and readily accessible anti-inflammatory and antiedema agent, with potent neuroprotective properties. We investigated whether PROG could serve as a viable alternative to DEXA in the management of peritumoral brain edema.

METHODS

We used an orthotopic C6 glioblastoma model with male Sprague-Dawley rats. Tumor grafts were allowed to grow for 14 days before drug treatment with DEXA 1 mg/kg, PROG 10 mg/kg, or PROG 20 mg/kg for 5 consecutive days. The overall animal survival and neurologic function were evaluated. Mechanistic studies on blood-brain barrier permeability and angiogenic responses were performed on the ex vivo tumor grafts.

RESULTS

We found that all drug treatments prolonged overall survival to different extents. PROG 10 mg led to significantly longer survival and better preservation of neurologic function and body weight. The blood-brain barrier permeability was better preserved with PROG 10 mg than with DEXA, possibly through downregulation of matrix metalloproteinase-9 and aquaporin-4 expression. Antiangiogenic responses were also observed in the PROG group.

CONCLUSIONS

The present proof-of-concept pilot study has provided novel information on the use of PROG as a corticosteroid-sparing agent in brain tumor management. Further translational and clinical studies are warranted.

The Efficacy of Acupuncture in Chemotherapy-Induced Peripheral Neuropathy: Systematic Review and Meta-Analysis

Background: Chemotherapy-induced peripheral neuropathy (CIPN) has no cure, but acupuncture may provide relief through its known neuromodulation or neuroendocrine adjustment. This review aimed to assess the efficacy of acupuncture in treating CIPN. Method: A literature review following the PRISMA Statement was performed, searching 7 databases from inception through August 2019. All studies were clinical trials of the effect of acupuncture on CIPN. The methodological quality of these trials was assessed using Cochrane criteria; meta-analysis software (RevMan 5.2) was used to analyze the data. Data Sources: The databases searched were the following: MEDLINE (Ovid), Embase, Cochrane CENTRAL, Scopus, World Health Organization International Clinical Trials Registry Platform, CNKI (China National Knowledge Infrastructure), and Wanfang Med Online. Results: We examined 386 cancer patients from 6 randomized control trials, which had high quality, based on the modified Jadad scale. Meta-analysis showed that acupuncture led to significant improvements in pain scores (-1.21, 95% confidence interval [CI] = -1.61 to -0.82, P < .00001) and nervous system symptoms based on Functional Assessment of Cancer Therapy/Neurotoxicity questionnaire scores (-2.02, 95% CI = -2.21 to -1.84, P < .00001). No significant change was noted in nerve conduction velocity (1.58, 95% CI = -2.67 to 5.83, P = .47). Conclusion: Acupuncture can effectively relieve CIPN pain and functional limitation. The limited number of subjects warrants a larger scale study.

Adverse drug reactions of anticancer drugs derived from natural sources

Cancer, a life threatening disease adversely affects huge population worldwide. Naturally derived drug discovery has emerged as a potential pathway in search of anticancers. Natural products-based drugs are generally considered safe, compared to their synthetic counterparts. A systematic review on adverse drugs reactions (ADRs) of the anticancer natural products has not been performed till date. We reviewed anticancer drugs, derived from plants, microbes and marine sources with their mechanistic action and reported ADRs. PubMed, ScienceDirect and Scopus were searched through Boolean information retrieval method using keywords "natural products", "cancer", "herbal", "marine drugs" and "adverse drug reaction". We documented ADRs of natural products based anticancer agents, mechanisms of action and chemical structures. It was observed that majority of the natural products based anticancer drugs possess ample adverse effects, dominantly hematological toxicities, alopecia, neurotoxicity and cardiotoxicity. These findings deviate from the preconceived notion about safer nature of herbal drugs. We also came across some anti-cancer natural products with less/no reported adverse events like Cabazitaxel and Arglabin. Comprehensive pharmacovigilance studies are needed to report ADRs and thereby predicting safety of anti-cancer drugs, either originated from natural sources or chemically synthesized.

Nerve Ultrasound, Electrophysiological, and Clinical Changes in Treatment-Naive Chronic Inflammatory Demyelinating Polyneuropathy: A Case Report

We report the case of a 74-year-old woman with treatment-naive chronic inflammatory demyelinating polyneuropathy evaluated by both nerve conduction studies and nerve ultrasound (NUS) before and after initial treatment. Performing both nerve conduction study and NUS before and after initial treatment seems rare for treatment-naive chronic inflammatory demyelinating polyneuropathy. This case yielded two major findings. First, improvement of nerve swelling as evaluated by NUS correlated well with the improvement of neurological symptoms. Second, NUS improvements were seen right after treatment, whereas electrophysiological improvements were not. Nerve ultrasound might thus allow for judgment of curative effects much more immediately and sensitively than nerve conduction study in treatment-naive chronic inflammatory demyelinating polyneuropathy.

A New Approach for Loading Anticancer Drugs Into Mesenchymal Stem Cell-Derived Exosome Mimetics for Cancer Therapy

Exosomes derived from mesenchymal stem cells (MSCs) have been evaluated for their potential to be used as drug delivery vehicles. Synthetically personalized exosome mimetics (EMs) could be the alternative vesicles for drug delivery. In this study, we aimed to isolate EMs from human MSCs. Cells were mixed with paclitaxel (PTX) and PTX-loaded EMs (PTX-MSC-EMs) were isolated and evaluated for their anticancer effects against breast cancer. EMs were isolated from human bone marrow-derived MSCs. MSCs (4 × 106 cells/mL) were mixed with or without PTX at different concentrations in phosphate-buffered saline (PBS) and serially extruded through 10-, 5-, and 1-μm polycarbonate membrane filters using a mini-extruder. MSCs were centrifuged to remove debris and the supernatant was filtered through a 0.22-μm filter, followed by ultracentrifugation to isolate EMs and drug-loaded EMs. EMs without encapsulated drug (MSC-EMs) and those with encapsulated PTX (PTX-MSC-EMs) were characterized by western blotting, nanoparticle tracking analysis (NTA), and transmission electron microscopy (TEM). The anticancer effects of MSC-EMs and PTX-MSC-EMs were assessed with breast cancer (MDA-MB-231) cells both in vitro and in vivo using optical imaging. EMs were isolated by the extrusion method and ultracentrifugation. The isolated vesicles were positive for membrane markers (ALIX and CD63) and negative for golgi (GM130) and endoplasmic (calnexin) marker proteins. NTA revealed the size of MSC-EM to be around 149 nm, while TEM confirmed its morphology. PTX-MSC-EMs significantly (p < 0.05) decreased the viability of MDA-MB-231 cells in vitro at increasing concentrations of EM. The in vivo tumor growth was significantly inhibited by PTX-MSC-EMs as compared to control and/or MSC-EMs. Thus, MSC-EMs were successfully isolated using simple procedures and drug-loaded MSC-EMs were shown to be therapeutically efficient for the treatment of breast cancer both in vitro and in vivo. MSC-EMs may be used as drug delivery vehicles for breast cancers.

Indibulin dampens microtubule dynamics and produces synergistic antiproliferative effect with vinblastine in MCF-7 cells: Implications in cancer chemotherapy

Indibulin, a synthetic inhibitor of tubulin assembly, has shown promising anticancer activity with a minimal neurotoxicity in preclinical animal studies and in Phase I clinical trials for cancer chemotherapy. Using time-lapse confocal microscopy, we show that indibulin dampens the dynamic instability of individual microtubules in live breast cancer cells. Indibulin treatment also perturbed the localization of end-binding proteins at the growing microtubule ends in MCF-7 cells. Indibulin reduced inter-kinetochoric tension, produced aberrant spindles, activated mitotic checkpoint proteins Mad2 and BubR1, and induced mitotic arrest in MCF-7 cells. Indibulin-treated MCF-7 cells underwent apoptosis-mediated cell death. Further, the combination of indibulin with an anticancer drug vinblastine was found to exert synergistic cytotoxic effects on MCF-7 cells. Interestingly, indibulin displayed a stronger effect on the undifferentiated neuroblastoma (SH-SY5Y) cells than the differentiated neuronal cells. Unlike indibulin, vinblastine and colchicine produced similar depolymerizing effects on microtubules in both differentiated and undifferentiated SH-SY5Y cells. The data indicated a possibility that indibulin may reduce chemotherapy-induced peripheral neuropathy in cancer patients.

Targeting B Cells and Plasma Cells in Glomerular Diseases: Translational Perspectives

The unique contributions of memory B cells and plasma cells in kidney diseases remain unclear. In this review, we evaluate the clinical experience with treatments directed at B cells, such as rituximab, and at plasma cells, such as proteasome inhibition, to shed light on the role of these two B lineage compartments in glomerular diseases. Specifically, analysis of these targeted interventions in diseases such as ANCA-associated vasculitis, SLE, and antibody-mediated transplant rejection permits insight into the pathogenetic effect of these cells. Notwithstanding the limitations of preclinical models and clinical studies (heterogeneous populations, among others), the data suggest that memory B and plasma cells represent two engines of autoimmunity, with variable involvement in these diseases. Whereas memory B cells and plasma cells appear to be key in ANCA-associated vasculitis and antibody-mediated transplant rejection, respectively, SLE seems likely to be driven by both autoimmune compartments. These conclusions have implications for the future development of targeted therapeutics in immune-mediated renal disease.

Neurotoxic effect of oxaliplatin: Comparison with its oxalate-free analogue cis-[PtII(1R,2R-DACH)(3-acetoxy-1,1-cyclobutanedicarboxylato)] (LLC-1402) in mice

Studies suggest that oxalate is involved in the development oxaliplatin-induced peripheral sensory neuropathy (OPSN). This study aimed to compare the neurotoxic effects of oxaliplatin with its oxalate-free cytotoxic analogue cis-[Pt^II(1R,2R-DACH)(3-acetoxy-1,1-cyclobutanedicarboxylato)] (LLC-1402) in mice. Oxaliplatin and LLC-1402 were intravenously injected in male Swiss mice with a total of nine injections. Oxalate was intraperitoneally injected in other animals. The development of OPSN was evaluated using mechanical and thermal sensitivity tests. Dorsal root ganglia of the mice were removed to evaluate c-Fos, ATF3 and iNOS expression and a sample of blood was collected for leukocyte count and hepatic and renal biochemical function tests. Oxaliplatin and LLC-1402 decreased the mechanical and thermal nociceptive threshold, whilst oxalate lead to a partial and later increase in the mechanical sensitivity (P<0.05). c-Fos, ATF3 and iNOS expressions were increased in neuronal cells during and after the end of the injections in animals treated with oxaliplatin and LLC-1402 (P<0.05), even though oxaliplatin lead to an earlier increase. Only c-Fos expression was elevated during the period of injections in the oxalate group (P<0.05), but this expression reduced after the end of the treatment. c-Fos expression was also shown in glial satellite cells only in the oxaliplatin-treated animals. Oxaliplatin and LLC-1402 reduced leukocyte count (P<0.05), but did not change renal and liver functions. In conclusion, oxalate may contribute to an earlier development of peripheral sensory neuropathy. However, the antitumor cytotoxic mechanism of oxaliplatin seems to be the main responsible by its neurotoxic effect.

Herbal medicines and chemotherapy induced peripheral neuropathy (CIPN): A critical literature review

BACKGROUND

Chemotherapy induced peripheral neuropathy [CIPN] is a common significant and debilitating side-effect resulting from the administration of neurotoxic chemotherapeutic agents. These pharmaco-chemotherapeutics can include taxanes, vinca alkaloids, platinum analogues, and others. Moderate to severe CIPN significantly decreases the quality of life and physical abilities of cancer patients and current pharmacotherapy for CIPN e.g. Amifostine, and antidepressants have had limited efficacy and may themselves induce adverse side-effects.

METHODS

To determine the potential use of herbal medicines as adjuvants in cancer treatments, a critical literature review was conducted by electronic and manual search on nine databases. These include PubMed, the Cochrane Library, Science Direct, Scopus, EMBASE, MEDLINE, Google Scholar, and two Chinese databases CNKI and CINAHL. Thirty-four studies were selected from 5614 studies assessed and comprising animal studies, case reports, retrospective studies, and minimal randomized clinical trials investigating the anti-CIPN effect of herbal medicines as the adjuvant intervention in patients administered chemotherapy. The thirty-four studies were assessed on methodological quality and limitations identified.

RESULTS

Studies were mixed in their recommendations for herbal medicines as an adjuvant treatment for CIPN.

CONCLUSION

Currently no agent has shown solid beneficial evidence to be recommended for the treatment or prophylaxis of CIPN. Given that the number of cancer survivors is increasing, the long-term side effects of cancer treatment, is of major importance.

Vascular complications in glioma patients

Vascular complications in patients with glioma most commonly include venous and arterial thromboembolism; however, treatment-induced vasculopathies are also problematic, especially in long-term survivors. The interactions between treatment such as radiation and chemotherapy, the coagulation cascade, endothelium, and regulators of angiogenesis are complex, drive glioma growth and invasion, and create common management problems in the clinic. We review the incidence of thrombotic complications in glioma, the biology of the coagulome as related to glioma progression, prevention and treatment of thrombosis, the role of anticoagulants as anticancer therapy, and vascular complications such as ischemic stroke and intracranial bleeding. The coagulation cascade is intimately involved in cancer-related thrombosis, glioma progression, and vascular complications of glioma therapy. Tissue factor is the principal initiator of coagulation and is upregulated in a glioma subtype-specific fashion. Short-term (perioperative) antithrombotic prophylaxis is effective, but long-term anticoagulation, although attractive, is not routinely indicated. Most patients with symptomatic venous thromboembolism can be safely anticoagulated, including those on anti-vascular endothelial growth factor therapeutics such as bevacizumab. Initial therapy should include low-molecular-weight heparin, and protracted anticoagulant treatment, perhaps indefinitely, is indicated. Many complex interactions resulting in vessel wall injury can lead to ischemic stroke, intracranial and intratumoral hemorrhage, and long-term sequelae such as cognitive impairment.

Macrophages as Active Nanocarriers for Targeted Early and Adjuvant Cancer Chemotherapy

Taking advantage of the highly permeable vasculature and lack of lymphatic drainage in solid tumors (EPR effect), nanosized drug delivery systems or nanomedicines have been extensively explored for tumor-targeted drug delivery. However, in most clinical cases tumors such as the early stage tumors and post-surgery microscopic residual tumors have not yet developed such pathological EPR features, i.e., EPR-deficient. Therefore, nanomedicines may not be applicable for such these tumors. Macrophages by nature can actively home and extravasate through the tight vascular wall into tumors and migrate to their hypoxic regions, and possess perfect stealth ability for long blood circulation and impressive phagocytosis for drug loadings. Thus, nanomedicines loaded in macrophages would harness both merits and gain the active tumor homing capability independent of the EPR effect for treatments of the EPR-deficient tumors. Herein, the critical considerations, current progress, challenges and future prospects of macrophages as carriers for nanomedicines are summarized, aiming at rational design of EPR-independent tumor-targeting active nanomedicines for targeted early and adjuvant cancer chemotherapy.

Bortezomib-associated demyelinating neuropathy--clinical and pathologic features

OBJECTIVES

Bortezomib is a proteasome inhibitor that is frequently used for multiple myeloma and lymphoma. A sensory predominant axonal neuropathy is associated with bortezomib treatment but a demyelinating neuropathy is also described primarily based on electrodiagnostic findings. We report a series of patients treated with bortezomib who developed peripheral neuropathy and were found to have demyelinating features on electrodiagnostic testing.

METHODS

Four patients who developed a bortezomib-induced peripheral neuropathy underwent electrophysiological testing, and 1 patient had a nerve biopsy.

RESULTS

The four patients with bortezomib-induced peripheral neuropathy had demyelinating features on their electrophysiological testing. The nerve biopsy performed in 1 patient demonstrated a demyelinating component in a background of axonal degeneration.

CONCLUSIONS

Although most toxic neuropathies are symmetrical axonal neuropathies, bortezomib is part of a small list of agents that may cause a demyelinating polyneuropathy and axonal degeneration. These findings have been confirmed by nerve biopsy.

Kinase inhibitors and monoclonal antibodies in oncology: clinical implications

Molecularly targeted cancer therapies, such as small-molecule kinase inhibitors and monoclonal antibodies, constitute a rapidly growing and an important part of the oncology armamentarium. Unlike conventional (cytotoxic) chemotherapeutics, targeted therapies were designed to disrupt cancer cell pathogenesis at specific biological points essential for the development and progression of the tumour. These agents were developed to disrupt specific targets with the aim of minimizing treatment burden compared with conventional chemotherapy. Nevertheless the increasingly common use of targeted therapies has revealed some unanticipated, often clinically significant toxic effects, as well as compromising effective palliative and end-of-life management approaches. Although patients and clinicians welcome improvements in cancer prognosis, these changes can also impact patient quality-of-life. Therefore, as demand for oncology expertise increases, physicians need to apprise themselves of targeted therapies and their clinical implications, including drug-specific side effects, impact on quality of life, and cost issues, especially in relation to end-of-life care. This Review provides a useful summary and guide for professionals treating patients with malignant diseases.

An Overview of Bortezomib-Induced Neurotoxicity

The boronic acid dipeptide bortezomib, able to induce tumor cell death by degradation of key proteins, is the first proteasome inhibitor drug to enter clinical practice. It is employed as first-line treatment in relapsed or resistant multiple myeloma (MM) patients. However, bortezomib often induces a dose-limiting toxicity in the form of painful sensory neuropathy, which can mainly be reduced by subcutaneous administration or dose modification. In this review we focus on the current understanding of the pathophysiological mechanisms of bortezomib-induced neuropathy to allow further studies in animal models and humans, including analysis of clinical and pharmacogenetic aspects, to optimize the treatment regimens.

Metformin inhibits growth of human glioblastoma cells and enhances therapeutic response

High-grade gliomas, glioblastomas (GB), are refractory to conventional treatment combining surgery, chemotherapy, mainly temozolomide, and radiotherapy. This highlights an urgent need to develop novel therapies and increase the efficacy of radio/chemotherapy for these very aggressive and malignant brain tumors. Recently, tumor metabolism became an interesting potential therapeutic target in various cancers. Accordingly, combining drugs targeting cell metabolism with appropriate chemotherapeutic agents or radiotherapy has become attractive. In light of these perspectives, we were particularly interested in the anti-cancer properties of a biguanide molecule used for type 2 diabetes treatment, metformin. In our present work, we demonstrate that metformin decreases mitochondrial-dependent ATP production and oxygen consumption and increases lactate and glycolytic ATP production. We show that metformin induces decreased proliferation, cell cycle arrest, autophagy, apoptosis and cell death in vitro with a concomitant activation of AMPK, Redd1 and inhibition of the mTOR pathway. Cell sensitivity to metformin also depends on the genetic and mutational backgrounds of the different GB cells used in this study, particularly their PTEN status. Interestingly, knockdown of AMPK and Redd1 with siRNA partially, but incompletely, abrogates the induction of apoptosis by metformin suggesting both AMPK/Redd1-dependent and –independent effects. However, the primary determinant of the effect of metformin on cell growth is the genetic and mutational backgrounds of the glioma cells. We further demonstrate that metformin treatment in combination with temozolomide and/or irradiation induces a synergistic anti-tumoral response in glioma cell lines. Xenografts performed in nude mice demonstrate in vivo that metformin delays tumor growth. As current treatments for GB commonly fail to cure, the need for more effective therapeutic options is overwhelming. Based on these results, metformin could represent a potential enhancer of the cytotoxic effects of temozolomide and/or radiotherapy.

Tumor extracellular acidity activated “off–on” release of bortezomib from a biocompatible dendrimer

A nanoparticle with a specific response to tumor extracellular acidity provides a new option in the design of tumor-targeted delivery systems.

Current use of drugs affecting the central nervous system for chemotherapy-induced peripheral neuropathy in cancer patients: a systematic review

PURPOSE

Chemotherapy-induced peripheral neuropathy (CIPN) is common among cancer patients who undergo chemotherapy with platinum analogues, taxanes, vinca alkaloids, epothilone, bortezomib, and thalidomide. The purpose of this study was to investigate the evidence of using drugs affecting the central nervous system (CNS) to alleviate CIPN in cancer patients.

METHODS

A systematic literature search was conducted using the CINAHL, EMBASE, and Medline databases to identify randomized controlled clinical trials (RCTs) reported in English up to 2013. We identified ten trials of CNS-acting drugs used to treat CIPN in cancer patients and reviewed efficacy and safety of CNS-acting drugs for CIPN using a standard data collection form. The risk of bias in each RCT was also assessed.

RESULTS

Antidepressants were used in six studies and anticonvulsants in four studies. We found positive results for amitriptyline (topical), venlafaxine, and oxcarbazepine in one study each, but the results were not sufficient to draw definite conclusions. One trial with duloxetine showed a moderate effect (effect size, 0.513, P = .003) on CIPN pain relief. However, none of the results has yet been duplicated in an RCT with a large sample size.

CONCLUSIONS

Insufficient RCTs exist to confirm the efficacy of CNS agents to reduce CIPN. This study highlighted the need for and the importance of conducting well-designed RCTs to generate evidence on CIPN symptom management. Additional RCTs are warranted to accelerate the potential use of CNS drugs for CIPN in cancer patients.

Treatment of multiple myeloma: thalidomide-, bortezomib-, and lenalidomide-induced peripheral neuropathy

Over the last 15 years, substantial progress has been made in the treatment of patients with multiple myeloma (MM). New chemotherapeutic options with the immunomodulatory drugs thalidomide and lenalidomide and with the proteasome inhibitor bortezomib have increased the response rates before and after autologous hematopoietic stem cell transplantation (ASCT). Incorporation of the novel agents into the treatment of newly diagnosed MM and at relapse is now standard of care also for patients with MM not eligible for ASCT. However, the use of thalidomide and bortezomib is frequently associated with a dose-limiting peripheral neuropathy. In order to take full advantage of the therapeutic potential, a risk assessment for neurotoxicity is needed on a case-by-case basis. This assessment includes pre-existing neurological symptoms due to the MM, any comorbidities, and past or planned treatment regimens. The aim is to achieve maximum efficacy while minimizing the risk of developing chemotherapy-induced polyneuropathy (CIPN). This requires a neurological evaluation of the patient at regular intervals, the implementation of preventive measures, and the development of validated therapeutic strategies for emerging neurotoxic side effects. This review focuses on the incidence, prevention, and management of peripheral neurotoxicity due to thalidomide, bortezomib, and lenalidomide in the treatment of MM.

Chemotherapy-induced peripheral neurotoxicity (CIPN): what we need and what we know

Chemotherapy-induced peripheral neurotoxicity (CIPN) is one of the most frequent and severe long-term side effects of cancer chemotherapy. Preclinical and clinical studies have extensively investigated CIPN searching for effective strategies to limit its severity or to treat CIPN-related impairment, but the results have been disappointing. Among the reasons for this failure are methodological flaws in both preclinical and clinical investigations. Their successful resolution might provide a brighter perspective for future studies. Among the several neurotoxic chemotherapy drugs, oxaliplatin may offer a clear example of a methodological approach eventually leading to successful clinical trials. However, the same considerations apply to the other neurotoxic agents and, although frequently neglected, also to the new "targeted" agents.

Central neurotoxicity of standard treatment in patients with newly-diagnosed high-grade glioma: a prospective longitudinal study

Following tumor resection, the majority of high-grade glioma (HGG) patients are treated with a combined modality regimen of radiotherapy and temozolomide. As a result of the tumor itself or as treatment-related neurotoxic side-effects, these patients may experience cognitive deficits. Additionally, radiological abnormalities expressed as white matter hyperintensities (WMH) and cerebral atrophy (CA) can develop. In this study, these functional and morphological parameters are evaluated, and their relation is investigated. After surgery, HGG patients underwent chemo-irradiation for six weeks, followed by six cycles of temozolomide. Assessments were performed before chemo-irradiation, post-concomitantly, after the third and sixth adjuvant cycle, and 3 and 7 months after treatment. Degree of WMH and CA was scored on MRI. Patients' neuropsychological performance was compared to healthy matched controls, yielding six cognitive domain z-scores. Development or progression of pre-existing WMH and CA during follow-up was observed in 36 and 45 % of the patients (n = 39) respectively. Cognitive functioning remained stable or improved in 70 % of the patients and deteriorated in 30 % of the patients (n = 33). Of the cognitive decliners, 80 % had tumor progression within 4 months thereafter. No clear association between cognitive functioning and WMH or CA was found. Central neurotoxic effects of combined modality treatment in HGG patients expressed by radiological abnormalities are encountered in approximately 40 % of patients. However, functional impact as indexed by cognitive functioning was found to be limited. Furthermore, development or progression of pre-existing WMH and CA does not consistently result in functional impairment as measured by cognitive tests.