Cognitive function after chemotherapy in adults with solid tumours

Chemotherapy-induced cognitive impairment and glia: A new take on chemobrain?

The significant rise in cancer survivorship stands out as one of the most notable achievements of modern science. However, this comes with a significant burden, as cancer treatment is not without adverse effects. Lately, there has been a growing focus on cognitive dysfunction associated with cancer treatment, often referred to as 'chemobrain'. It significantly impacts the quality of life for cancer survivors. The underlying mechanisms studied so far usually focus on neurons, while other cells of the central nervous system are often overlooked. This review seeks to place the hypothesis that glial cells may play a role in the development of chemotherapy-induced cognitive dysfunction. It summarizes the primary mechanisms proposed to date while underscoring the existing gaps in this research field. Inflammation and release of pro-inflammatory mediators by M1 microglia and A1 astrocytes are the most prevalent findings after chemotherapy. However, activation of A1 astrocytes by some chemotherapeutic agents may contribute to neuronal degeneration, alterations in synaptic branches, as well as glutamate excitotoxicity, which can contribute to cognitive impairment. Furthermore, the reduction in the number of oligodendrocytes after chemotherapy may also impact the myelin sheath, contributing to 'chemobrain'. Furthermore, some chemotherapeutic drugs activate M1 microglia, which is associated with decreased neuroplasticity and, possibly, cognitive impairment. In conclusion, data regarding the effects of chemotherapy on glial cells are scarce, and it is essential to understand how these cells are affected after cancer treatment to enable reliable therapeutic or preventive actions on cancer-treated patients.

Nanotechnology Approaches for Prevention and Treatment of Chemotherapy-Induced Neurotoxicity, Neuropathy, and Cardiomyopathy in Breast and Ovarian Cancer Survivors

Nanotechnology has emerged as a promising approach for the targeted delivery of therapeutic agents while improving their efficacy and safety. As a result, nanomaterial development for the selective targeting of cancers, with the possibility of treating off-target, detrimental sequelae caused by chemotherapy, is an important area of research. Breast and ovarian cancer are among the most common cancer types in women, and chemotherapy is an essential treatment modality for these diseases. However, chemotherapy-induced neurotoxicity, neuropathy, and cardiomyopathy are common side effects that can affect breast and ovarian cancer survivors quality of life. Therefore, there is an urgent need to develop effective prevention and treatment strategies for these adverse effects. Nanoparticles (NPs) have extreme potential for enhancing therapeutic efficacy but require continued research to elucidate beneficial interventions for women cancer survivors. In short, nanotechnology-based approaches have emerged as promising strategies for preventing and treating chemotherapy-induced neurotoxicity, neuropathy, and cardiomyopathy. NP-based drug delivery systems and therapeutics have shown potential for reducing the side effects of chemotherapeutics while improving drug efficacy. In this article, the latest nanotechnology approaches and their potential for the prevention and treatment of chemotherapy-induced neurotoxicity, neuropathy, and cardiomyopathy in breast and ovarian cancer survivors are discussed.

Patient-Reported Factors Impacting Memory and Cognition Among Women Currently or Previously Receiving Treatment for Breast Cancer

Objectives Cognitive impairments associated with cancer and cancer treatments have yet to determine definitive causes, gold-standard assessments, or effective treatments to offset or mitigate symptoms. The purpose of the current study was to determine relationships between women with breast cancer and the negative memory impact of treatment and other factors. Materials and methods This online study included 171 participants receiving at least one type of treatment for breast cancer. This descriptive correlational study used two measures to assess memory and one for stress. The survey included demographics, treatments received, and memory. Results Results indicated increased perceived impairments among variables of age, stress, surgery, chemotherapy, radiation, and hormonal treatment modalities. Discussion This study established relationships between memory/cognitive impairments and the variables of age, four treatment modalities, three agents, and stress. Conclusion The results from this study demonstrate the importance of developing standardized assessments to identify the presence and severity of cancer and treatment-related cognitive impairments. The study will be used as a first step to developing a memory support strategy using a web-based nursing intervention considering the impact of stress.

Comparative Effects of Exercise Interventions and Mindfulness-Based Interventions for Cognitive Impairment and Quality of Life in Breast Cancer Survivors During or After Cancer Treatment: A Systematic Review and Bayesian Network Meta-analysis

OBJECTIVE

The aim of this network meta-analysis was to compare the improvement effects of various exercise interventions and mindfulness-based interventions to determine the best interventions for the improvement of cognitive impairment.

DESIGN

Seven databases were searched to screen randomized controlled trials of exercise interventions and mindfulness-based interventions to improve cognitive impairment. The network meta-analysis was performed using Revman 5.3, R 4.2.1 and ADDIS 1.16.8 software.

RESULTS

Thirty-four randomized controlled trials involving 14 interventions were included in the study. In terms of cognitive function, except for mindfulness-based stress reduction, all interventions showed significantly greater improvement in cognitive function compared with conventional therapy. Physical activity and Qigong showed better effect in improving executive function. In terms of improving verbal memory, compensatory cognitive training, neurofeedback training, Qigong, and sham Qigong were more effective than other interventions. On performing surface under the cumulative ranking curve analysis, acceptance and commitment therapy, neurofeedback training, Qigong, and mediation had the best effects on cognitive function, quality of life, executive function, and processing speed, respectively.

CONCLUSIONS

Mindfulness-based interventions were found to be more effective than exercise interventions for alleviating cognitive impairment. More robust randomized controlled trials focusing on acceptance and commitment therapy for cognitive impairment are required to support the current evidence.

Coenzyme Q10 ameliorates chemotherapy-induced cognitive impairment in mice: a preclinical study

BACKGROUND

Among the three most used anticancer drugs, cyclophosphamide, Adriamycin, and 5-Fluorouracil (CAF), the most significant outcome is chemobrain, caused by increased oxidative stress, inflammatory insult, and mitochondrial dysfunction.

OBJECTIVE

In this study, endogenous antioxidant coenzyme Q10 (CoQ10) was evaluated for its neuroprotective effects in CICI.

MATERIALS AND METHODS

The chemobrain was induced in Swiss albino female mice by administering CAF (40 + 4 + 25 mg/kg) intraperitoneal (i.p.) in three cycles (single injection per week) followed by treatment with CoQ10 (40 mg/kg; p.o.) for up to 3 weeks followed by behavioral, biochemical, molecular and histopathological analysis.

RESULTS

Treatment with CoQ10 significantly improved cognition by improving exploring time in novel objects recognition test followed by increasing the time spent in the target quadrant in MWM test as compared to CAF-treated animals. Moreover, CoQ10 demonstrated antioxidant properties by reducing the expression of LPO while increasing levels of GSH, SOD, and catalase as compared to CAF-treated animals. While the levels of AChEs were significantly reduced after CoQ10 treatment in CAF-treated animals. In terms of its mechanism, it effectively counteracted the pro-inflammatory substances (TNF-α and IL-1β) triggered by CAF while also enhancing the levels of anti-inflammatory markers (IL-10 and Nrf2). Moreover, CoQ10 showed mitochondrial enhancers and it improved the level of Complex (I, II, and IV). Besides that, mitochondrial morphological analysis was done by TEM, and neuronal morphology along with quantification analysis was performed by H&E staining using Image J software to confirm the neuroprotective effect of CoQ10 over CAF-induced cognitive impairment.

CONCLUSION

This study suggests CoQ10 can protect the mitochondria by imposing antioxidant, and anti-inflammatory properties, which could be a potential therapy for CICI.

Cognitive impairment following breast cancer treatments: an umbrella review

OBJECTIVES

Cancer-related cognitive impairment (CRCI) refers to a cognitive decline associated with cancer or its treatments. While research into CRCI is expanding, evidence remains scattered due to differences in study designs, methodologies, and definitions. The present umbrella review aims to provide a comprehensive overview of the current evidence regarding the impact of different breast cancer therapies on cognitive functioning, with a particular focus on the interplay among objective cognitive deficits (ie, measured with standardized tests), subjective cognitive concerns, (ie, self-reported), and other mediating psycho-physical factors.

METHODS

The search was made in Pubmed, Embase, and Scopus for articles published until July 2023, following the guidelines of the Preferred Reporting Items for Systematic Reviews and Meta-analysis protocol.

RESULTS

Chemotherapy and endocrine therapy appear consistently associated with CRCI in patients with breast cancer, primarily affecting memory, attention/concentration, executive functioning, and processing speed. Subjective cognitive concerns were often found weakly or not associated with neuropsychological test results, while overall CRCI seemed consistently associated with psychological distress, fatigue, sleep quality, and inflammatory and biological factors.

CONCLUSION

Current evidence suggests that CRCI is common after chemotherapy and endocrine therapy for breast cancer. However, heterogeneity in study designs and the scarcity of studies on more recent treatments such as targeted therapies and immunotherapies, highlight the need for more systematic and harmonized studies, possibly taking into account the complex and multifactorial etiology of CRCI. This may provide valuable insights into CRCI's underlying mechanisms and potential new ways to treat it.

Postoperative Nausea and Vomiting in Female Patients Undergoing Laparoscopic Gastrointestinal Surgery with Double Prophylactic Therapy

Purpose  Postoperative nausea and vomiting (PONV) is a major problem after surgery. This study aimed to demonstrate the incidence of PONV and the potential associated factors in female patients undergoing laparoscopic gastrointestinal surgery against the background of double prophylactic therapy. Methods  Our retrospective study recruited 109 female patients undergoing laparoscopic gastrointestinal surgery with double prophylactic therapy, combining palonosetron with dexamethasone, from October 2020 to March 2021, at the Sixth Affiliated Hospital of Sun Yat-sen University, Guangzhou, China. Patient characteristics and perioperative management factors were included in univariate and multivariate analyses to identify factors influencing PONV. Results  Four patients lacked complete records, and of the 105 patients included in the final analysis, 53 (50.5%) patients developed PONV. Two influencing factors for PONV were identified: a history of chemotherapy (odds ratio [OR] 0.325, 95% confidence interval [CI] 0.123-0.856; p  = 0.023) and dosage of hydromorphone ≥ 0.02 mg/kg (OR 2.857, 95% CI 1.247-6.550; p  = 0.013). The performance of the multivariate logistic regression was evaluated by analyzing receiver operating characteristic curves, resulting in an area under the curve value of 0.673. Conclusion  The incidence of PONV remains high in female patients undergoing laparoscopic gastrointestinal surgery, even with double prophylactic therapy. A dosage of hydromorphone ≥ 0.02 mg/kg may increase risk of PONV, whereas a history of chemotherapy might be a protective factor.

Ondansetron attenuates cisplatin-induced behavioral and cognitive impairment through downregulation of NOD-like receptor inflammasome pathway

Cisplatin is an effective and commonly used chemotherapeutic drug; however, its use is accompanied by several adverse effects, including chemobrain. Ondansetron is a 5-HT3 antagonist, commonly used in prophylactic against chemotherapy-induced nausea and vomiting. Moreover, it has been identified as a novel neuroprotective agent in different animal models. However, its protective role against chemotherapy-induced chemobrain has not been investigated. The current study was the first study that explored the potential neuroprotective effect of ondansetron against cisplatin-induced chemobrain in rats. Cisplatin (5 mg/Kg) was injected intraperitoneally, once weekly, for 4 weeks with the daily administration of ondansetron (0.5 and 1 mg/Kg). Compared to the cisplatin-treated group, ondansetron administration showed a significant decrease in the latency time and a significant increase in ambulation, rearing, and grooming frequency in the open field test (OFT). Moreover, a significant improvement in the latency time in the rotarod and passive avoidance tests, following ondansetron administration. In addition, ondansetron treatment increased the percentage of alternation in the Y-maze test. Also, ondansetron showed a remarkable enhancement in the biochemical parameters in the hippocampus. It increased the acetylcholine (Ach) level and decreased the level of the acetylcholine esterase enzyme (AchE). Ondansetron significantly decreased interleukin-1β (Il-1β), tumor necrosis factor-alpha (TNF-α), toll-like receptor-4 (TLR-4), NOD-like receptor-3 (NLRP3) inflammasome as well as caspase-1 and caspase-3 levels. Furthermore, ondansetron significantly decreased the levels of copper transporter-1(CTR1) expression in the hippocampus. Collectively, these findings suggest that ondansetron may exhibit a neuroprotective and therapeutic activity against cisplatin-induced chemobrain.

Chemotherapy-induced cognitive impairment in breast cancer survivors: A systematic review of studies from 2000 to 2021

BACKGROUND

Studies have indicated that apart from enhancing patient survival, chemotherapy has adverse side effects on the psychological, social, and cognitive functions of breast cancer survivors.

AIMS

This study was conducted to understand chemotherapy's impact on breast cancer survivors' cognitive functions.

METHODS AND RESULTS

Our study is a systematic review based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. We searched English databases, including PubMed/MEDLINE, PsycINFO, and Web of Science, and Persian databases, such as Irandoc and Elmnet, using Persian keywords of cancer, breast cancer, chemotherapy, cognitive functions, executive functions, and neuropsychological functions. Two reviewers independently evaluated the full text of the articles according to predefined criteria. Among the 937 available studies, 26 were selected based on the inclusion and exclusion criteria, of which 17 (65%) were longitudinal and 9 (35%) were cross-sectional. The findings indicated a significant relationship between the use of chemotherapy and cognitive impairments, most notably attention, working and short-term memory, and executive functions. However, the studies differed in their findings regarding the long-term persistence of cancer-related cognitive impairment (CRCI), which could be due to the wide range of tools used, different methods to measure cognitive functions, and the difference in the sample size of the studies.

CONCLUSION

Chemotherapy, affecting cortical and subcortical brain structures, causes a set of cognitive impairments that can lead to impairments in social responsibility acceptance, daily functioning, and quality of life of women. Therefore, rigorous and extensive research design is required to understand the causes and consequences of CRCI using standardized and sensitive measures of cognitive functions. Specifically, studies comparing the effects of different chemotherapy regimens on cognition and potential mechanisms and/or moderators of CRCI would be instrumental in designing more effective therapy regimens and evaluating the efficacy and cost-effectiveness of cognitive rehabilitation and supportive care programs.

Treadmill exercise ameliorates chemotherapy-induced memory impairment through Wnt/β-catenin signaling pathway

Doxorubicin (DOX) is a widely used chemotherapy drug for various cancers and it is known to induce cognitive impairment. The aim of this study was to investigate the effect of treadmill exercise on chemotherapy-induced memory impairment. We assessed whether DOX affects inflammation, mitochondrial Ca2+ retention capacity, and Wnt/β-catenin signaling. Male Sprague-Dawley rats were divided into control group, exercise group, DOX-injection group, and DOX-injection and exercise group. To create a DOX-induced memory impairment model, animals were injected intraperitoneally with DOX (2 mg/kg) dissolved in saline solution once a week for 4 weeks. Treadmill exercise was performed once a day, 5 days a week, for 8 consecutive weeks. Short-term memory was determined using the step-down avoidance test. Western blot was performed for the proinflammatory cytokines, Wnt/β-catenin signaling, brain-derived neurotrophic factor (BDNF), tropomyosin receptor kinase B (TrkB) in the hippocampus. Mitochondrial Ca2+ retention capacity in the hippocampus was also measured. DOX-injection rats showed deterioration of short-term memory along with decreased expression of BDNF and TrkB in the hippocampus. Levels of the proinflammatory cytokines, tumor necrosis factor-α and interleukin-6, were increased in the DOX-injection rats. Wnt/β-catenin signaling was activated and mitochondrial Ca2+ retention capacity was decreased in the DOX-injection rats. However, treadmill exercise alleviated short-term memory impairment, decreased proinflammatory cytokines, increased BDNF and TrkB expression, and enhanced mitochondrial Ca2+ retention capacity. Treadmill exercise restorated Wnt/β-catenin signaling pathway. This study demonstrated that treadmill exercise can be used for patients undergoing chemotherapy with DOX.

Recommendations on the Selection, Development, and Modification of Performance Outcome Assessments: A Good Practices Report of an ISPOR Task Force

In evaluating the clinical benefit of new therapeutic interventions, it is critical that the treatment outcomes assessed reflect aspects of health that are clinically important and meaningful to patients. Performance outcome (PerfO) assessments are measurements based on standardized tasks actively undertaken by a patient that reflect physical, cognitive, sensory, and other functional skills that bring meaning to people's lives. PerfO assessments can have substantial value as drug development tools when the concepts of interest being measured best suit task performance and in cases where patients may be limited in their capacity for self-report. In their development, selection, and modification, including the evaluation and documentation of validity, reliability, usability, and interpretability, the good practice recommendations established for other clinical outcome assessment types should continue to be followed, with concept elicitation as a critical foundation. In addition, the importance of standardization, and the need to ensure feasibility and safety, as well as their utility in patient groups, such as pediatric populations, or those with cognitive and psychiatric challenges, may enhance the need for structured pilot evaluations, additional cognitive interviewing, and evaluation of quantitative data, such as that which would support concept confirmation or provide ecological evidence and other forms of construct evidence within a unitary approach to validity. The opportunity for PerfO assessments to inform key areas of clinical benefit is substantial and establishing good practices in their selection or development, validation, and implementation, as well as how they reflect meaningful aspects of health is critical to ensuring high standards and in furthering patient-focused drug development.

Protective Effect of Galantamine against Doxorubicin-Induced Neurotoxicity

BACKGROUND AND AIMS

Doxorubicin (DOX) causes cognitive impairment (chemobrain) in patients with cancer. While DOX damages the cholinergic system, few studies have focused on the protective effects of cholinergic function on chemobrain. The acetylcholinesterase inhibitor galantamine (GAL) demonstrates neuroprotective properties. We investigated the mechanisms associated with DOX-induced cognitive impairments and the potential protective role of GAL in preventing chemobrain.

MAIN METHODS

Female Wistar rats were divided into control, DOX, GAL, and DOX + GAL groups. The rats in the DOX group were administered DOX (5 mg/kg intraperitoneally twice weekly for two weeks), while those in the GAL group were orally administered GAL (2.5 mg/kg) via oral gavage once daily for 15 days. The combination group (DOX + GAL) received GAL (once daily) and DOX (two times per week) concurrently. The body weights and survival rates were monitored daily. The animals were subjected to behavioral tests to assess the memory function followed by the biochemical estimation of inflammatory markers, including tumor necrosis factor-α (TNF-α), interleukine-1β (IL-1β), and interleukine-6 (IL-6) in rat brain tissue and RT-qPCR.

KEY FINDINGS

DOX caused a reduction in the body weight and survival rate, which was alleviated by GAL concomitant treatment with DOX (DOX + GAL). These groups had reduced body weights and survival rates. DOX-treated animals exhibited an impairment of short-term spatial working memory, manifested as a behavioral alteration in the Y-maze test, the novel object recognition (NOR) test, and the elevated plus-maze (EPM) test. Concurrent treatment with GAL (DOX + GAL) showed improved memory function, as evidenced by an increase in the number of entries and time spent in the novel arm, the time spent exploring the novel object, and the transfer latency in the Y-maze, NOR test, and EPM test, respectively. These findings were also supported by biochemical observations showing the reversal of DOX-induced changes in IL-1β, IL-6, and TNF-α, as well as their relative expression of mRNA in brain tissue following concurrent GAL treatment.

CONCLUSION

GAL appeared to be a neuroprotective agent against neuroinflammation caused by DOX by reducing inflammatory markers in the brain.

Engineered Phage-Based Cancer Vaccines: Current Advances and Future Directions

Bacteriophages have emerged as versatile tools in the field of bioengineering, with enormous potential in tissue engineering, vaccine development, and immunotherapy. The genetic makeup of phages can be harnessed for the development of novel DNA vaccines and antigen display systems, as they can provide a highly organized and repetitive presentation of antigens to immune cells. Bacteriophages have opened new possibilities for the targeting of specific molecular determinants of cancer cells. Phages can be used as anticancer agents and carriers of imaging molecules and therapeutics. In this review, we explored the role of bacteriophages and bacteriophage engineering in targeted cancer therapy. The question of how the engineered bacteriophages can interact with the biological and immunological systems is emphasized to comprehend the underlying mechanism of phage use in cancer immunotherapy. The effectiveness of phage display technology in identifying high-affinity ligands for substrates, such as cancer cells and tumor-associated molecules, and the emerging field of phage engineering and its potential in the development of effective cancer treatments are discussed. We also highlight phage usage in clinical trials as well as the related patents. This review provides a new insight into engineered phage-based cancer vaccines.

Heterotopic 4T1 breast cancer transplantation induces hippocampal inflammation and depressive-like behaviors in mice

Cancer and its accompanying treatments can lead to numerous physical and emotional concerns, including subclinical or clinical depression and anxiety, which could significantly impact one's well-being, quality of life, and survival. A large number of studies have elucidated that neuroinflammation is associated with depression. Here, we report the hippocampal pathological changes and depressive behaviors of a heterotopic breast cancer transplantation mouse model; hence, a heterotopic 4T1 breast cancer transplantation mouse model was established. Assessment of cognitive and locomotive functions of the experimental animals was conducted using open- and closed-field tests, including a tail suspension test. Expression levels of monoaminergic system markers, brain-derived neurotrophic factor (BDNF), pro-inflammatory cytokines, and nuclear factor-kappa B (NFκB) in the hippocampus and serum were detected using immunochemistry and western and enzyme-linked immunosorbent assay analysis. A comparison of the differences between model and control animals was performed. As per our findings, 4T1 tumor-bearing mice displayed cancer-related anorexia/cachexia with significant reductions in the travel distance and the total number of squares crossed in the open- and closed-field tests. Additionally, the 4T1 tumor-bearing mice withstood a more extended period of immobility during the tail suspension test. Immunohistochemistry studies revealed reduced levels of serotonin, norepinephrine, and BDNF in the hippocampus and serum. Elevated levels of NFκB and pro-inflammatory cytokines in the hippocampus were also observed. These findings suggest that hippocampal inflammation may have played an important role in the neurological function and depressive behavior in heterotopic 4T1 breast cancer transplantation mice.

Emerging roles of toll-like receptor 4 in chemotherapy-induced neurotoxicity

Chemotherapy-induced neurotoxicity is one of the most prevalent side effects in cancer patients and survivors. Cognitive decline and peripheral neuropathy are the most common chemotherapy-induced neurotoxic symptoms. These symptoms lead not only to the limiting of the dose of chemotherapy given to cancer patients, but also have an impact on the quality of life of cancer survivors. Although the exact mechanisms involved in chemotherapy-induced neurotoxicity are still unclear, neuroinflammation is widely regarded as being one of the major causes involved in chemotherapy-induced neurotoxicity. It is known that Toll-like receptor 4 (TLR4) plays a critical role in the inflammatory process, and it has been recently reported that it is associated with chemotherapy-induced neurotoxicity. In this review, we summarize and discuss all available evidence regarding the activation of the TLR4 signaling pathway in various models of chemotherapy-induced neurotoxicity. This review also emphasizes the evidence pertinent to TLR4 inhibition on chemotherapy-induced neurotoxicity in rodent studies. Understanding the role of the TLR4 signaling pathway behind chemotherapy-induced neurotoxicity is crucial for improving treatments and ensuring the long-term survival of cancer patients.

Induced pluripotent stem cell-derived brain organoids as potential human model system for chemotherapy induced CNS toxicity

Neurotoxic phenomena are among the most common side effects of cytotoxic agents. The development of chemotherapy-induced polyneuropathy (CIPN) is a well-recognized adverse reaction in the peripheral nervous system, while changes of cognitive functions (post-chemotherapy cognitive impairment (PCCI)) are more diffuse and have only recently drawn scientific interest. PCCI in patients most often displays as short-term memory loss, reduced multitasking ability or deficits in language. Not least, due to a lack of preclinical human model systems, the underlying molecular mechanisms are poorly understood, and treatments are missing. We thus investigated whether induced pluripotent stem cell (iPSC)-derived brain organoids can serve as a human model system for the study of chemotherapy induced central nervous system toxicity. We robustly generated mature brain organoids from iPSC-derived neuronal precursor cells (NPC), which showed a typical composition with 1) dividing NPCs forming ventricle like structures 2) matured neurons and 3) supporting glial cells closer to the surface. Furthermore, upon stimulation the brain organoids showed functional signaling. When exposed to increasing concentrations of paclitaxel, a frequently used chemotherapy drug, we observed time dependent neurotoxicity with an EC50 of 153 nM, comparable to a published murine model system. Histological analysis after paclitaxel exposure demonstrated dose dependent apoptosis induction and reduced proliferation in the organoids with further Western blot analyses indicating the degradation of neuronal calcium sensor one protein (NCS-1) and activation of Caspase-3. We could also provide evidence that paclitaxel treatment negatively affects the pool of neuronal and astrocyte precursor cells as well as mature neurons. In summary our data suggests that human iPSC derived brain organoids are a promising preclinical model system to investigate molecular mechanisms underlying PCCI and to develop novel prevention and treatment strategies.

Rationale and design of the prevention of paclitaxel-related neurological side effects with lithium trial - Protocol of a multicenter, randomized, double-blind, placebo- controlled proof-of-concept phase-2 clinical trial

Introduction

Chemotherapy-induced polyneuropathy (CIPN) and post-chemotherapy cognitive impairment (PCCI) are frequent side effects of paclitaxel treatment. CIPN/PCCI are potentially irreversible, reduce quality of life and often lead to treatment limitations, which affect patients' outcome. We previously demonstrated that paclitaxel enhances an interaction of the Neuronal calcium sensor-1 protein (NCS-1) with the Inositol-1,4,5-trisphosphate receptor (InsP3R), which disrupts calcium homeostasis and triggers neuronal cell death via the calcium-dependent protease calpain in dorsal root ganglia neurons and neuronal precursor cells. Prophylactic treatment of rodents with lithium inhibits the NCS1-InsP3R interaction and ameliorates paclitaxel-induced polyneuropathy and cognitive impairment, which is in part supported by limited retrospective clinical data in patients treated with lithium carbonate at the time of chemotherapy. Currently no data are available from a prospective clinical trial to demonstrate its efficacy.

Methods and analysis

The PREPARE study will be conducted as a multicenter, randomized, double-blind, placebo-controlled phase-2 trial with parallel group design. N = 84 patients with breast cancer will be randomized 1:1 to either lithium carbonate treatment (targeted serum concentration 0.5-0.8 mmol/l) or placebo with sham dose adjustments as add-on to (nab-) paclitaxel. The primary endpoint is the validated Total Neuropathy Score reduced (TNSr) at 2 weeks after the last (nab-) paclitaxel infusion. The aim is to show that the lithium carbonate group is superior to the placebo group, meaning that the mean TNSr after (nab-) paclitaxel is lower in the lithium carbonate group than in the placebo group. Secondary endpoints include: (1) severity of CIPN, (2) amount and dose of pain medication, (3) cumulative dose of (nab-) paclitaxel, (4) patient-reported symptoms of CIPN, quality of life and symptoms of anxiety and depression, (5) severity of cognitive impairment, (6) hippocampal volume and changes in structural/functional connectivity and (7) serum Neurofilament light chain protein concentrations.

Ethics and dissemination

The study protocol was approved by the Berlin ethics committee (reference: 21/232 - IV E 10) and the respective federal agency (Bundesinstitut für Arzneimittel und Medizinprodukte, reference: 61-3910-4044771). The results of the study will be published in peer-reviewed medical journals as well as presented at relevant (inter)national conferences.

Clinical trial registration

[https://www.drks.de/drks_web/navigate.do?navigationId=trial.HTML&TRIAL_ID=DRKS00027165], identifier [DRKS00027165].

Comparative analysis of the chemotherapy-related cognitive impairments in patients with breast cancer: a community-based research

This study aimed to evaluate the effects of two common chemotherapy regimens on breast cancer (BC) survivors' cognition. The participants comprised 35 patients with BC who underwent two chemotherapy regimens, AC-T and TAC, and 24 matched healthy volunteers. The participants were assessed regarding cognitive function through Addenbrooke's Cognitive Examination and Cambridge Brain Science tests. The results represent the AC-T regimen to be more toxic than the TAC in domains of language, concentration, and visuospatial working memory (P-value =0.036, 0.008, and 0.031, respectively) and should be prescribed with caution in patients with BC suffering from baseline cognitive impairments.

Patient-reported outcomes and chemotherapy-related cognitive impairment in gynecologic malignancy

OBJECTIVE

Chemotherapy has multiple adverse effects, including chemotherapy-related cognitive impairment, the phenomenon colloquially referred to as 'chemobrain'. The objective of this study was to understand patient-reported experiences of this phenomenon in relation to chemotherapy administration among gynecologic oncology patients.

METHODS

A prospective patient-reported outcomes program was implemented in the Gynecologic Oncology clinic of a tertiary academic institution in January 2018. Patients with endometrial or ovarian cancer who received chemotherapy were included through September 2019 in this cohort study. Patients completed the European Organization for the Research and Treatment of Cancer Quality of Life Questionnaire. Serial responses were compared before, during, and after chemotherapy using a mixed effects linear regression with random effects for repeated measures within patients and a fixed effect for endometrial versus ovarian cancer.

RESULTS

Fifty patients were included who completed a total of 152 patient-reported outcome measures. Thirty-five questionnaires were administered before chemotherapy, 59 during treatment, and 58 at a median of 161 days after the final cycle of chemotherapy. Seventy-one percent of patients reported no difficulties with concentration before chemotherapy, which remained stable after chemotherapy (72%). Sixty-six percent reported no difficulty with memory before chemotherapy versus 52% after chemotherapy. There were significant differences in feeling tension (p<0.001), worry (p<0.001), and depression (p=0.02) before and after chemotherapy on mixed effects linear regression, with higher levels of adverse emotional symptoms before chemotherapy administration compared with after. Women reported more interference with their social lives during chemotherapy (mean 1.08) compared with before (mean 0.85) and after chemotherapy (0.75, p=0.04).

CONCLUSIONS

While no overt memory issues were discovered with serial administration of patient-reported outcome measures, rates of adverse emotional symptoms such as depression, tension, and worry diminished after chemotherapy administration. Further study is needed about the phenomenon of chemotherapy-related cognitive impairment using a larger cohort.

Chemobrain in Breast Cancer: Mechanisms, Clinical Manifestations, and Potential Interventions

Among the potential adverse effects of breast cancer treatment, chemotherapy-related cognitive impairment (CRCI) has gained increased attention in the past years. In this review, we provide an overview of the literature regarding CRCI in breast cancer, focusing on three main aspects. The first aspect relates to the molecular mechanisms linking individual drugs commonly used to treat breast cancer and CRCI, which include oxidative stress and inflammation, reduced neurogenesis, reduced levels of specific neurotransmitters, alterations in neuronal dendrites and spines, and impairment in myelin production. The second aspect is related to the clinical characteristics of CRCI in patients with breast cancer treated with different drug combinations. Data suggest the incidence rates of CRCI in breast cancer vary considerably, and may affect more than 50% of treated patients. Both chemotherapy regimens with or without anthracyclines have been associated with CRCI manifestations. While cross-sectional studies suggest the presence of symptoms up to 20 years after treatment, longitudinal studies confirm cognitive impairments lasting for at most 4 years after the end of chemotherapy. The third and final aspect is related to possible therapeutic interventions. Although there is still no standard of care to treat CRCI, several pharmacological and non-pharmacological approaches have shown interesting results. In summary, even if cognitive impairments derived from chemotherapy resolve with time, awareness of CRCI is crucial to provide patients with a better understanding of the syndrome and to offer them the best care directed at improving quality of life.

Anticancer and Neuroprotective Activities of Ethyl Acetate Fractions from Morus macroura Miq. Plant Organs with Ultraperformance Liquid Chromatography-Electrospray Ionization-Tandem Mass Spectrometry Profiling

Column chromatography afforded the isolation of seven secondary metabolites (1-(2,4,6-trihydroxy phenyl)-ethanone-4-O-β-d-glucopyranoside, naringenin-7-O-β-d-glucopyranoside, kaempferol-3-O-α-l-rhamnoside, kaempferol-3-O-β-d-glucopyranoside, quercetin-3-O-β-d-glucopyranoside, quercetin-3-O-β-d-galactopyranoside, rutin) from the ethyl acetate (ET) fractions of Morus macroura Miq. stems (S), leaves (L), and fruits (F). Their identification based on ultraviolet (UV), electron ionization (EI), electrospray ionization-mass spectrometry (ESI-MS), and 1D and 2D NMR data. In addition, profiling of ET fractions using ultraperformance liquid chromatography-electrospray ionization-tandem mass spectrometry (UPLC-ESI-MS/MS) resulted in the identification of 82 compounds belonging to different classes, mainly polyphenolic constituents. Chemical profiling as well as molecular docking directed us to biological evaluation. Interestingly, the ET-L fraction exhibited a robust cytotoxic activity against HepG-2, MCF-7, and HELA cell lines. Also, it displayed a neuromodulatory activity against cisplatin neurotoxicity in rats by ameliorating the neurobehavioral dysfunction visualized in the open field and Y-maze test and modulating the neurochemical parameters such as brain amino acid levels (glutamate, aspartate, serine, and histidine), oxidative stress markers (GSH, MDA, and 8-hydroxy-2'-deoxyguanosine), and purinergic cell energy (adenosine triphosphate (ATP) and adenosine monophosphate (AMP)). In conclusion, the isolated compounds (kaempferol-3-O-β-glucoside and quercetin-3-O-β-glucoside) from the ET-L fraction could serve as potent anticancer agents due to their strong antioxidant, in vitro cytotoxicity, and in vivo neuroprotective activity.

Long-Term Cognitive Dysfunction in Cancer Survivors

Cancer-related cognitive impairment (CRCI) is a frequent side effect experienced by an increasing number of cancer survivors with a significant impact on their quality of life. Different definitions and means of evaluation have been used in available literature; hence the exact incidence of CRCI remains unknown. CRCI can be described as cognitive symptoms reported by cancer patients in self-reported questionnaires or as cognitive changes evaluated by formal neuropsychological tests. Nevertheless, association between cognitive symptoms and objectively assessed cognitive changes is relatively weak or absent. Studies have focused especially on breast cancer patients, but CRCI has been reported in multiple types of cancer, including colorectal, lung, ovarian, prostate, testicular cancer and hematological malignancies. While CRCI has been associated with various treatment modalities, including radiotherapy, chemotherapy, hormone therapy and novel systemic therapies, it has been also detected prior to cancer treatment. Therefore, the effects of cancer itself with or without the psychological distress may be involved in the pathogenesis of CRCI as a result of altered coping mechanisms after cancer diagnosis. The development of CRCI is probably multifactorial and the exact mechanisms are currently not completely understood. Possible risk factors include administered treatment, genetic predisposition, age and psychological factors such as anxiety, depression or fatigue. Multiple mechanisms are suggested to be responsible for CRCI, including direct neurotoxic injury of systemic treatment and radiation while other indirect contributing mechanisms are hypothesized. Chronic neuroinflammation mediated by active innate immune system, DNA-damage or endothelial dysfunction is hypothesized to be a central mechanism of CRCI pathogenesis. There is increasing evidence of potential plasma (e.g., damage associated molecular patterns, inflammatory components, circulating microRNAs, exosomes, short-chain fatty acids, and others), cerebrospinal fluid and radiological biomarkers of cognitive dysfunction in cancer patients. Discovery of biomarkers of cognitive impairment is crucial for early identification of cancer patients at increased risk for the development of CRCI or development of treatment strategies to lower the burden of CRCI on long-term quality of life. This review summarizes current literature on CRCI with a focus on long-term effects of different cancer treatments, possible risk factors, mechanisms and promising biomarkers.

The Effects of 5-Fluorouracil/Leucovorin Chemotherapy on Cognitive Function in Male Mice

5-Fluorouracil (5-Fu) and leucovorin (LV) are often given in combination to treat colorectal cancer. 5-Fu/LV prevents cell proliferation by inhibiting thymidylate synthase, which catalyzes the conversion of deoxyuridine monophosphate to deoxythymidine monophosphate. While 5-Fu has been shown to cause cognitive impairment, the synergistic effect of 5-Fu with LV has not been fully explored. The present investigation was designed to assess how the combination of 5-Fu and LV affect cognition in a murine model. Six-month-old male mice were used in this study; 15 mice received saline injections and 15 mice received 5-Fu/LV injections. One month after treatment, the elevated plus maze, Y-maze, and Morris water maze behavioral tasks were performed. Brains were then extracted, cryosectioned, and stained for CD68 to assay microglial activation and with tomato lectin to assay the vasculature. All animals were able to locate the visible and hidden platform locations in the water maze. However, a significant impairment in spatial memory retention was observed in the probe trial after the first day of hidden-platform training (first probe trial) in animals that received 5-Fu/LV, but these animals showed spatial memory retention by day 5. There were no significant increases in inflammation as measured by CD68, but 5-Fu/LV treatment did modulate blood vessel morphology. Tandem mass tag proteomics analysis identified 6,049 proteins, 7 of which were differentially expressed with a p-value of <0.05 and a fold change of >1.5. The present data demonstrate that 5-Fu/LV increases anxiety and significantly impairs spatial memory retention.

The diuretic amiloride attenuates doxorubicin-induced chemobrain in rats: Behavioral and mechanistic study

Cognitive impairment or "chemobrain" is a troublesome adverse effect which had been increasingly reported by cancer patients after doxorubicin (DOX) chemotherapy. Notably, Hypertension, a very common comorbidity in cancer patients, could pose a greater risk for negative cognitive outcomes. Amiloride (AML) is an antihypertensive, potassium-sparing diuretic that has been proven to be neuroprotective in different experimental models; this can be attributed to its ability to inhibit different ion transporters such as Na^+/H⁺ exchanger (NHE), which upon excessive activation can result in intracellular cationic overload, followed by oxidative damage and cellular death. Accordingly, this study was designed to investigate the potential neuroprotective effect of AML against DOX-induced chemobrain and to elucidate possible underlying mechanisms. Briefly, Histopathological examination and neurobehavioral testing (Morris water maze, Y maze and passive avoidance test) showed that AML co-treatment (10 mg/kg/day) markedly attenuated DOX (2 mg/kg/week)-induced neurodegeneration and memory impairment after 4 weeks of treatments. We found that DOX administration up-regulated NHE expression and increased lactic acid content in the hippocampus which were markedly opposed by AML. Moreover, AML mitigated DOX-induced neuroinflammation and decreased hippocampal tumor necrosis factor-α level, nuclear factor kappa-B, and cyclooxygenase-2 expression. Additionally, AML counteracted DOX-induced hippocampal oxidative stress as indicated by normalized malondialdehyde and glutathione levels. Furthermore, AML halted DOX-induced hippocampal apoptosis as evidenced by decreased caspase-3 activity and lower cytochrome c immunoexpression. Our results in addition to the previously reported antitumor effects of AML and its ability to mitigate cancer resistance to DOX therapy could point toward possible new repositioning scenarios of the diuretic AML especially regarding hypertensive cancer patients.

Behavioral and morphological effects of resveratrol and curcumin in rats submitted to doxorubicin-induced cognitive impairment

Doxorubicin (DOX) is known to cause cognitive impairments in patients submitted to long-term chemotherapy (deficits also known as chemobrain). Therefore, there is an urgent need for therapeutic strategies capable of returning cancer survivors back to their previous quality of life. The present study investigated whether resveratrol (RSV) or curcumin (CUR) administration could affect mnemonic function and brain morphological changes following DOX administration in rats. Male Wistar rats were divided into 4 groups: DOX group (2.5 mg/kg/week for 4 weeks, i.p., plus distilled water for 28 days, oral gavage - OG), DOX + RSV group (DOX, 2.5 mg/kg/week for 4 weeks, i.p., plus RSV, 10 mg/kg/day for 28 days, OG), DOX + CUR group (DOX, 2.5 mg/kg/week for 4 weeks, i.p., plus CUR, 100 mg/kg/day for 28 days, OG) and control (CTR) group (0.9% saline solution weekly for 4 weeks, i.p., plus distilled water for 28 days, OG). Behavioral analyses (open field - OF - and the novel object recognition test - NORT) were performed. Brains were collected and analyzed by hematoxylin-eosin and luxol fast blue staining techniques and by immunohistochemistry for GFAP (glial fibrillary acidic protein) expression in astrocytes and Iba1 (ionized calcium-binding adaptor molecule 1) expression in microglia. DOX-injected rats presented short-term and long-term memory impairments as seen in the NORT at 3 and 24 h after habituation and increased GFAP and Iba1 expression, respectively, in astrocytes and microglia of the frontal cortex, hypothalamus and hippocampus. Such cognitive deficits were prevented by CUR at both periods and by RSV at 24 h. DOX-induced astrogliosis and microgliosis were avoided by RSV and CUR. No signs of demyelination or neuronal loss were found in any group. Thus, CUR and RSV prevented memory loss, astrogliosis and microgliosis induced by DOX monotherapy.

Study of Chemotherapy-Induced Cognitive Impairment in Women with Breast Cancer

Background: Oncology patients experience a large number of symptoms and, those referring to cognitive performance has an ever-increasing importance in clinical practice, due to the increase in survival rates and interest in the patient’s quality of life. The studies reviewed showed that chemotherapy-related cognitive impairment might occur in 15 and 50% of oncology patients. The main objective of this research was to study the impact of chemotherapy on the cognitive function of patients with locoregional breast cancer. Method: Analytical, prospective, longitudinal study using three measures, unifactorial intrasubject design, non-probability, and random selection sampling. The sample comprised women newly diagnosed with locoregional breast cancer in stages I, II, IIIA who received chemotherapy at the University Hospital of Salamanca (Complejo Asistencial Universitario de Salamanca), randomly selected for three years. Semi-structured interviews were conducted, and anxiety and depression (Hospital Anxiety and Depression scale, HAD); quality of life (QLQ-BR23 scale) and the following cognitive variables were assessed—processing speed, attention, memory, and executive functions (subtests of the Wechsler Intelligence Scale and the Trail Making Test). Results: The final sample size included 151 participants; 23 were excluded. A decline in cognitive performance was observed in patients, which did not completely recover two months after chemotherapy was completed. Additionally, worse cognitive performance was observed in patients with anxious or depressive symptoms. There was a negative impact on the quality of life. Conclusion: Chemotherapy had an impact on the cognitive performance of oncology patients in most cognitive domains studied.

Changes in Fatigue, Psychological Distress, and Quality of Life After Chemotherapy in Women with Breast Cancer: A Prospective Study

BACKGROUND

Chemotherapy leads to various symptoms and psychological distress, which contribute to a significant decrease in the quality of life of the patients.

OBJECTIVES

The aim of this study was to identify changes and interrelationships in the fatigue-depression-anxiety symptom cluster and quality of life during the cancer care trajectory in women with breast cancer.

METHODS

Fifty women participated in the study and completed questionnaires at 3 different times: prechemotherapy, postchemotherapy, and 6 months after the completion of chemotherapy. The assessment tools were the Functional Assessment of Cancer Therapy-Fatigue Scale, Hospital Anxiety and Depression Scale, and Functional Assessment of Cancer Therapy-Breast Cancer version 4 Scale. Data were analyzed using descriptive and repeated-measures analysis of variance statistics.

RESULTS

A significant increase in fatigue (F = 41.95, P < .001) and psychological distress (F = 26.55, P < .001) from prechemotherapy to postchemotherapy was noted. Improvement was observed 6 months after the completion of chemotherapy. A positive or negative change in fatigue was associated with the same in psychological distress. Quality of life (F = 65.22, P < .001) also showed similar change patterns as observed with fatigue and psychological distress. Fatigue had a greater impact on quality of life at postchemotherapy, but psychological distress had a greater impact at prechemotherapy and at the 6-month follow-up.

CONCLUSION

These results suggest that chemotherapy is highly associated with the fatigue-depression-anxiety symptom cluster and quality of life in women with breast cancer.

IMPLICATIONS FOR PRACTICE

Nursing intervention is needed to relieve the intensity of the fatigue-depression-anxiety symptom cluster and thus improve the quality of life of patients undergoing chemotherapy from before treatment to follow-up.

Chemotherapy-induced cognitive impairment from the forensic medicine perspective: A review of the updated literature

Chemotherapy treatments in some neoplastic patients can cause unwanted side-effects that can be accompanied by a physical weakening due to changes in executive functioning, processing speed and reaction times with a consequent inability to carry out daily life activities (ADL) or a working disability due to the loss of working memory and the inability to organize fundamental skills, influencing the quality of everyday life. Although chemotherapy-induced cognitive impairment (CICI), also known as post-chemotherapy cognitive impairment (PCCI), chemo-brain or chemo-fog, has been described in the literature since the late 1980s, the neurobiological factors behind this pathology to date are not yet fully understood. According to the finding of most studies conducted on patients affected by different forms of neoplastic diseases, there are strong enough evidence of a prominent role of some drug such as doxorubicin, cyclophosphamide, cytarabine, methotrexate, 5-fluorouracil and cisplatin in causing chemo-fog related neurological impairment. The physical incapacity that affects the patients seems, therefore, to be related to the cytotoxic effects that the chemotherapy drugs exert on the central nervous system, causing a short or long-term neurological decline. Cognitive dysfunctions could influence individual self-determination by configuring a state of transient or habitual mental infirmity capable of altering the preservation of the person's voluntary faculties, with potential consequences on the legal validity of any deeds signed by the person. The growing interest in this pathological condition by the forensic medicine community is due precisely to the non-negligible medico-legal implications that derive from it affecting aspects of private law. In this article, a review of the literature on chemotherapy-induced cognitive impairment and related issues that may arise in forensic medicine and private law was conducted.

Chemotherapy-induced cognitive impairment (CICI): An overview of etiology and pathogenesis

Many cancer patients treated with chemotherapy develop chemotherapy-induced cognitive impairment (CICI), often referred to as chemo-brain, which manifest during or post-treatment with variable degrees, onset and duration thereby affecting the patients' quality of life. Several chemotherapeutic agents have been studied to determine its possible association with cognitive impairment and to fully comprehend their contribution to CICI. A vast number of studies have emerged proposing several candidate underlying mechanisms and etiologies contributing to CICI such as direct neurotoxicity, BBB disruption, decreased hippocampal neurogenesis, white matter abnormalities, secondary neuro-inflammatory response and increased oxidative stress; however, the exact underlying mechanisms are still not well defined. This review summarizes CICI associated with most commonly used chemotherapeutic agents with emphasizes the possible underlying pathogenesis in both animal and clinical studies.

Cognitive dysfunction in patients with nasopharyngeal carcinoma after induction chemotherapy

OBJECTIVE

This prospective study aimed to assess the incidence, details of the change of cognitive dysfunction, and predictive factors of cognitive function impairment associated with induction chemotherapy (IC) in nasopharyngeal carcinoma (NPC) patients.

METHOD

We prospectively included NPC patients who treated with IC from December 2018 to January 2020. Montreal cognitive assessment (MoCA) was used to measure cognitive function, and score less than 26 was defined as cognitive dysfunction. Multivariate logistic regression analysis was applied to assess the independent predictors associated with cognitive function impairment.

RESULTS

A total of 76 patients were recruited, 10 patients were excluded due to refusal or unable to finish the questionnaire, and 66 patients were analyzed in this study. The median age of the patients was 48.5 years (range, 24-69 years). There was 89.4% of patients received ≥3 circles of IC. For the entire group, 27.3% had cognitive dysfunction, of which attention, language, short-term memory, and orientation showed significant downward trends, while visuospatial/executive function, naming, and abstraction demonstrated no prominent decrease. In patients having cognitive function impairment, 77.8% of them occurred after the first circle of IC. Gender (P = 0.039) and education (P = 0.03) were significant predictors for cognitive dysfunction. Female patients (female vs. male: 50% vs. 20%) and patients with lower educational levels (lower vs. higher: 37.8% vs. 11.8%) were more likely to suffer cognitive dysfunction. In addition, age (P = 0.572) and chemotherapy circles (P = 0.68) had no association with cognitive dysfunction.

CONCLUSION

Approximately 25% of NPC patients suffered cognitive dysfunction after IC, especially in female patients and patients with lower educational levels.

Correlates of cognitive impairment in adult cancer survivors who have received chemotherapy and report cognitive problems

OBJECTIVE

Cognitive impairment negatively affects some cancer survivors who have completed chemotherapy; however, factors underlying this cognitive impairment remain poorly understood. We aimed to investigate (1) the relative importance of demographics, medical, and psychological characteristics associated with cognitive impairment and (2) the specific variables associated with cognitive impairment in adult cancer survivors who completed adjuvant chemotherapy.

METHODS

We performed post hoc analyses of baseline data from early-stage cancer survivors with cognitive complaints who received adjuvant chemotherapy 0.5-5 years earlier and volunteered for a trial designed to improve cognition. The primary outcome of self-reported cognitive impairment was measured using a questionnaire; secondary outcome of objective cognitive impairment was measured using a computerized neuropsychological test battery. Hierarchical linear regression determined the relative importance of demographics, medical, and psychological characteristics in associations with both self-reported and objective cognitive impairment.

RESULTS

The sample was 95% female and 89% breast cancer patients. The final model accounted for 33% of variation in self-reported cognitive impairment (n = 212, demographics 5%, medical 3%, and psychological 25%), with fatigue and stress as significant individual correlates (p values ≤ 0.0001). For the secondary analysis, the final model accounted for 19% of variation in objective cognitive impairment (n = 206, demographics 10%, medical 5%, and psychological 4%), with age, smoking history, and number of chemotherapy cycles as significant individual correlates.

CONCLUSION

We found that psychological characteristics are more important than demographic and medical characteristics in self-reported cognitive impairment, whereas other characteristics are more important in objective cognitive impairment. This suggests clinicians should investigate possible psychological problems in cancer survivors who self-report cognitive impairment.

Taxane-induced neurotoxicity: Pathophysiology and therapeutic perspectives

Taxane-derived drugs are antineoplastic agents used for the treatment of highly common malignancies. Paclitaxel and docetaxel are the most commonly used taxanes; however, other drugs and formulations have been used, such as cabazitaxel and nab-paclitaxel. Taxane treatment is associated with neurotoxicity, a well-known and relevant side effect, very prevalent amongst patients undergoing chemotherapy. Painful peripheral neuropathy is the most dose-limiting side effect of taxanes, affecting up to 97% of paclitaxel-treated patients. Central neurotoxicity is an emerging side effect of taxanes and it is characterized by cognitive impairment and encephalopathy. Besides impairing compliance to chemotherapy treatment, taxane-induced neurotoxicity (TIN) can adversely affect the patient's life quality on a long-term basis. Despite the clinical relevance, not many reviews have comprehensively addressed taxane-induced neurotoxicity when they are used therapeutically. This article provides an up-to-date review on the pathophysiology of TIN and the novel potential therapies to prevent or treat this side effect.

Connectome analysis of brain functional network alterations in breast cancer survivors with and without chemotherapy

Purpose

Treatment modalities for breast cancer, the leading cause of cancer-related deaths in women worldwide, include surgery, radiotherapy, adjuvant chemotherapy, targeted therapy, and hormonal therapy. The advancement in medical technology has facilitated substantial reduction in breast cancer mortality. However, patients may experience cognitive impairment after chemotherapy. This phenomenon called chemotherapy-induced cognitive impairment (i.e., “chemobrain”) is common among breast cancer survivors. However, cognitive function deficits may exist before chemotherapy initiation. This study examined the functional network alterations in breast survivors by using resting-state functional magnetic resonance imaging (fMRI).

Methods

We recruited 172 female participants and separated them into three groups: C+ (57 breast cancer survivors who had finished 3–12-month-long chemotherapy), C- (45 breast cancer survivors who had not undergone chemotherapy), and HC (70 participants with no breast cancer history). We analyzed mean fractional amplitudes of low-frequency fluctuation and graph theoretical topologies from resting-state fMRI and applied network-based analysis to portray functional changes among the three groups.

Results

Among the three groups, the C- group demonstrated hyperactivity in the prefrontal cortex, bilateral middle temporal gyrus, right inferior temporal gyrus and right angular gyrus. Only the left caudate demonstrated significantly more hypoactivity in the C- group than in the C+ group. Graph theoretical analysis demonstrated that the brains of the C+ group became inclined toward regular networks and the brains of the C- group became inclined toward random networks.

Conclusion

Subtle alterations were noted in the brain activity and networks of our cancer survivors. Moreover, functional network disruptions occurred regardless of chemotherapeutic agent administration.

A mouse model of chemotherapy-related cognitive impairments integrating the risk factors of aging and APOE4 genotype

Some cancer survivors experience marked cognitive impairment, referred to as cancer-related cognitive impairment (CRCI). CRCI has been linked to the genetic factor APOE4, the strongest genetic risk factor for Alzheimer's disease (AD). We used APOE knock-in mice to test whether the relationship between APOE4 and CRCI can be demonstrated in a mouse model, to identify associations of chemotherapy with behavioural and structural correlates of cognition, and to test whether chemotherapy affects markers of AD. Twelve-month old C57BL/6 J female APOE3 (n = 30) and APOE4 (n = 31) knock-in mice were randomized to treatment with either doxorubicin (10 mg/kg) or saline. Behavioural assays at 2-21 weeks-post exposure included open field maze, elevated zero maze, pre-pulse inhibition, Barnes maze, and fear conditioning. Ex-vivo magnetic resonance imaging was used to determine regional volume differences at 31-35 weeks-post exposure, and tissue sections were analyzed for markers of AD pathogenesis. Minimal toxicities were observed in the aged mice after doxorubicin exposure. In the Barnes maze assay, APOE3 mice did not exhibit impairment in spatial learning after doxorubicin treatment, but APOE4 mice demonstrated significant impairments in both the initial identification of the escape hole and the latency to full escape at 6 weeks post-exposure. Both APOE3 and APOE4 mice treated with doxorubicin showed impairment of spatial memory. Grey matter volume in the frontal cortex decreased in APOE4 mice treated with doxorubicin vs. APOE3 mice. This study demonstrates cognitive impairments in aged APOE4 knock-in mice after doxorubicin treatment and establishes this system as a novel and powerful model of CRCI.

Curcumin attenuates cognitive impairment by enhancing autophagy in chemotherapy

Cisplatin, a commonly used chemotherapy drug, can increase the survival rate of cancer patients. However, it often causes various side effects, including neuronal deficit-induced cognitive impairment. Considering that curcumin is effective in neuronal protection, the action of curcumin on cognitive improvement was evaluated in cisplatin-treated C57BL/6 mice in the present study. Our results first showed that curcumin restored impaired cognitive behaviors. Consistent with this, neurogenesis and synaptogenesis were improved by curcumin. In addition, cisplatin-induced dysfunction of apoptosis-related proteins was partly reversed by curcumin. Moreover, cisplatin-induced autophagy was enhanced by curcumin. Our results also indicated that cisplatin induced autophagy through the endoplasmic reticulum (ER) stress-mediated ATF4-Akt-mTOR signaling pathway. Curcumin activated AMPK-JNK signaling, which mediated both mTOR inhibition and Bcl-2 upregulation and in turn enhanced autophagy and suppressed apoptosis, respectively. In contrast, pretreatment with the autophagy inhibitor 3-methyladenine (3-MA) completely abolished the effects of curcumin on cognitive improvement and improved neurogenesis, synaptogenesis and autophagy. Our results show that cognitive improvement induced by curcumin during chemotherapy is mediated by the enhancement of hippocampal autophagy.

Investigating Relationship between Pre- and Post- Chemotherapy Cognitive Performance with Levels of Depression and Anxiety in Breast Cancer Patients: A Cross-Sectional Study

INTRODUCTION

Evidence suggests that cancer and chemotherapy-related cognitive impairments are an important clinical issue that can have a negative impact on the quality of life (QOL) of many cancer patients during and after treatment. The aim of the current study was to investigate the relationship between cognitive performance before and after chemotherapy with levels of depression and anxiety in patients with breast cancer.

MATERIALS AND METHODS

This cross-sectional descriptive-analytical study was performed on 100 women with breast cancer in south of Iran. Patients included in the study were evaluated for cognitive performance before chemotherapy and 1, 3, and 6 months after chemotherapy. Patients' cognitive performance was assessed by Mini-Mental State Examination (MMSE). Patients were also assessed for their level of anxiety and depression using Beck Depression Inventory (BDI) and Beck Anxiety Inventory (BAI). Descriptive tests (percentage, frequency and mean) and ANOVA test used for statistical analysis.

RESULTS

Results of ANOVA test showed a significant difference between the cognitive performance of patients with breast cancer at 1, 3, and 6 months after chemotherapy compared to pre- chemotherapy phase. The above test also revealed a significant relationship between cognitive performance of patients and anxiety and depression.

CONCLUSION

The results showed that, due to the decrease in cognitive performance and increased anxiety and depression after initiation of chemotherapy in patients with breast cancer, it is necessary to closely monitor the mental and psychological status of these patients by their family and the treatment staffs so that the patient be able to cope with the disease more optimally and to recover.

Cognitive impairment after cytotoxic chemotherapy

Background

Neurotoxicity is a frequent side effect of cytotoxic chemotherapy and affects a large number of patients. Despite the high medical need, few research efforts have addressed the impact of cytotoxic agents on cognition (ie, postchemotherapy cognitive impairment; PCCI). One unsolved question is whether individual cytotoxic drugs have differential effects on cognition. We thus examine the current state of research regarding PCCI. Neurological symptoms after targeted therapies and immunotherapies are not part of this review.

Methods

A literature search was conducted in the PubMed database, and 1215 articles were reviewed for predefined inclusion and exclusion criteria. Thirty articles were included in the systematic review.

Results

Twenty-five of the included studies report significant cognitive impairment. Of these, 21 studies investigated patients with breast cancer. Patients mainly received combinations of 5-fluorouracil, epirubicin, cyclophosphamide, doxorubicin, and taxanes (FEC/FEC-T). Five studies found no significant cognitive impairment in chemotherapy patients. Of these, 2 studies investigated patients with colon cancer receiving 5-fluorouracil and oxaliplatin (FOLFOX). Independent risk factors for PCCI were patient age, mood alterations, cognitive reserve, and the presence of apolipoprotein E e4 alleles.

Conclusions

There is evidence that certain chemotherapy regimens cause PCCI more frequently than others as evidenced by 21 out of 23 studies in breast cancer patients (mainly FEC-T), whereas 2 out of 3 studies with colon cancer patients (FOLFOX) did not observe significant changes. Further studies are needed defining patient cohorts by treatment protocol in addition to cancer type to elucidate the effects of individual cytotoxic drugs on cognitive functions.

Nicotinic treatment of post-chemotherapy subjective cognitive impairment: a pilot study

PURPOSE

Persistent chemotherapy-related cognitive impairment (pCRCI) is commonly reported following cancer treatment and negatively affects quality of life; however, there is currently no pharmacological treatment indicated for pCRCI. This pilot study obtained preliminary data regarding the use of transdermal nicotine patches as a therapeutic strategy for women with pCRCI to (1) reduce subjective cognitive complaints and (2) enhance objective cognitive performance in breast, colon, lymphoma, or ovarian cancer survivors with pCRCI.

METHODS

Participants were randomized to either placebo (n = 11) or transdermal nicotine (n = 11) for 6 weeks, followed by 2 weeks of treatment withdrawal for a total of 8 weeks. Participants were assessed using both subjective and objective measures of cognitive functioning at five visits before, during, and after treatment.

RESULTS

Over the course of the study, women in both groups improved substantially in severity of self-reported cognitive complaints measured by Functional Assessment of Cancer Therapy-Cognitive Function Perceived Cognitive Impairments regardless of treatment arm. Additionally, objective cognitive performance measures improved in both groups; however, there was no significant difference in improvement between groups.

CONCLUSIONS

Due to a large placebo response, we were unable to determine if a drug effect was present. However, we did observe substantial improvement in self-reported cognitive symptoms, likely resulting from factors related to participation in the trial rather than specific drug treatment effects.

TRIAL REGISTRATION

The study was registered with clinicaltrials.gov (trial registration: NCT02312943).

IMPLICATIONS FOR CANCER SURVIVORS

These results suggest that women with pCRCI can exhibit improvement in subjective cognition, with attention paid to symptoms and close follow-up over a short period of time.

Chemobrain in rats: Behavioral, morphological, oxidative and inflammatory effects of doxorubicin administration

Doxorubicin (DOX) is known to cause cognitive impairments in patients submitted to long-term chemotherapy (deficits also known as chemobrain). The present study investigated whether DOX administration could affect behavior and brain morphology, as well as oxidative and inflammatory status in rats. Male Wistar rats were injected with DOX (2.5 mg/kg/week, 4 weeks, i.p.) or saline. Behavioral analyses were performed. Brains were collected and analyzed by hematoxylin-eosin and luxol fast blue staining techniques and by immunohistochemistry (for glial fibrillary acidic protein expression in astrocytes; GFAP). Serum and brain levels of TNF-α, IL-1β, IL-6, IL-8, IL-10 and CXCL-1 were determined. Oxidative parameters, such as superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione reductase (GR), nitric oxide (NO•), brain iron and ferritin levels, as well as reduced and oxidized glutathione (GSH and GSSG, respectively) and thiobarbituric acid reactive substances (TBARS) were also assessed in brain. DOX-injected rats presented cognitive/memory impairments, increased GFAP expression, increased levels of TBARS, NO and GR, but decreased GSSG and ferritin levels in brain homogenate. In addition, increased serum and brain levels of IL-6, IL-8 and CXCL1 were noted in the DOX group, although IL-10 decreased. As DOX has a poor penetration across the blood-brain barrier (BBB), it is proposed that this drug elicits a systemic proinflammatory response with increase of proinflammatory cytokines which cross the BBB and can be involved in the induction of oxidative molecules and proinflammatory cytokines that altogether induce astrogliosis all over the brain. These events may be responsable for chemotherapy-induced cognitive/memory deficits.

[A Structural Model for Chemotherapy Related Cognitive Impairment and Quality of Life in Breast Cancer Patients]

PURPOSE

This study aimed to develop and test a structural model for chemotherapy-related cognitive impairment of breast cancer patients based on a literature review and Hess and Insel's chemotherapy-related cognitive change model.

METHODS

The Participants consisted of 250 patients who were ≥19 years of age. The assessment tools included the Menopause Rating Scale, Symptom Experience Scale, Hospital Anxiety and Depression Scale, Everyday Cognition, and Functional Assessment of Cancer Therapy-Breast Cancer. Data were analyzed using the SPSS 21.0 and AMOS 21.0 programs.

RESULTS

The modified model was a good fit for the data. The model fit indices were χ²=423.18 (p<.001), χ²/df=3.38, CFI=.91, NFI=.91, TLI=.89, SRMR=.05, RMSEA=.09, and AIC=515.18. Chemotherapy-related cognitive impairment was directly influenced by menopausal symptoms (β=.38, p=.002), depression and anxiety (β=.25, p=.002), and symptom experiences (β=.19, p=.012). These predictors explained 47.7% of the variance in chemotherapy-related cognitive impairment. Depression and anxiety mediated the relations among menopausal symptoms, symptom experiences, and with chemotherapy related cognitive impairment. Depression and anxiety (β=-.51, p=.001), symptom experiences (β=-.27, p=.001), menopausal symptoms (β=-.22, p=.008), and chemotherapy-related cognitive impairment (β=-.15, p=.024) had direct effects on the quality of life and these variables explained 91.3%.

CONCLUSION

These results suggest that chemotherapy-related toxicity is highly associated with cognitive decline and quality of life in women with breast cancer. Depression and anxiety increased vulnerability to cognitive impairment after chemotherapy. Nursing intervention is needed to relieve chemotherapy-related toxicity and psychological factor as well as cognitive decline for quality of life in patients undergoing chemotherapy.

Differences in depressive and anxiety symptoms between cancer and noncancer patients with psychological distress

BACKGROUND

Cancer patients are particularly vulnerable to psychological problems. The purpose of the present study was to compare differences in psychological difficulties, including depression and anxiety, between cancer patients and noncancer patients. This study assessed the differences in depressive and anxiety symptoms between patients with and without cancer.

MATERIALS AND METHODS

Participants included 219 patients at The Cancer Center, Dongnam Institute of Radiological and Medical Sciences, Busan, Korea, who reported depressive or anxiety symptoms between April 2014 and April 2016. Patients were categorized into cancer and noncancer groups based on medical histories showing a diagnosis of any type of cancer. The Beck Depression Inventory (BDI) and Beck Anxiety Inventory (BAI) were used to evaluate psychological distress at each patient's first visit. Patients' charts were reviewed for clinical data, including BDI and BAI scores and duration of cancer treatment, and for demographic data such as age and sex.

RESULTS

The results showed that patients in the cancer group experienced greater discomfort related to somatic symptoms; higher BDI subscale scores were related to work difficulties, insomnia, loss of appetite, somatic worries (fatigue), and loss of libido compared with patients in the noncancer group. The BAI subscale scores for fear of the worst happening, feeling unsteady, feeling terrified or afraid, a sense of choking, fear of dying, and feeling scared were higher in patients with than in those without cancer.

CONCLUSION

High levels of depressive symptoms related to somatic discomfort and anxiety symptoms related to fear of cancer were associated with considerable psychological distress in patients with cancer diagnosis and treatment.

Effects of neoadjuvant chemotherapy on the depth of total intravenous anesthesia in patients with breast cancer undergoing unilateral modified radical mastectomy: A prospective observational study

Toxic effects of neoadjuvant chemotherapy (NC) on nervous, hepatorenal, and pulmonary systems might affect general anesthesia depth. This study aimed to evaluate the effects of NC on depth of total intravenous anesthesia.This prospective observational study enrolled 60 patients undergoing elective unilateral modified radical mastectomy during total intravenous anesthesia with propofol and remifentanil (January-June 2015; Liaocheng People's Hospital, China): the NC group (n = 30) received NC, while the control group (n = 30) did not. Propofol and remifentanil dosages were adjusted according to indexes of consciousness (IoC1: sedation; IoC2: analgesia) to control fluctuations of blood pressure and heart rate within 20% of baseline values. Parameters reflecting propofol/remifentanil dosages, intraoperative adverse events, and quality of anesthetic recovery were recorded.The duration of propofol infusion (1.3 ± 0.4 vs 1.8 ± 0.5 hours, P < .05), mean propofol dosage (8.0 ± 1.0 vs 9.3 ± 1.5 mg kg h, P < .05), and adjustment frequency of target-controlled remifentanil infusion (2.9 ± 1.8 vs 4.4 ± 2.6 times/surgery, P < .05) were significantly lower in the NC group than in the control group; adjustment frequency of target-controlled propofol infusion was also numerically lower (2.0 ± 1.1 vs 2.7 ± 1.5 times/surgery, P = .053). Duration of remifentanil infusion, mean remifentanil dosage, voluntary eye opening, extubation time, and recovery score were not significantly different between groups. The incidence of tachycardia was lower in the NC group than in the control group (7.1% vs 37.0%, P < .05), but there was no significant difference in the incidence of total adverse events between groups.NC can enhance the sensitivity of breast cancer patients to the anesthetic effect of propofol.

Does walking protect against decline in cognitive functioning among breast cancer patients undergoing chemotherapy? Results from a small randomised controlled trial

BACKGROUND

Cancer related cognitive impairments have been subjectively reported and objectively detected in breast cancer patients treated with chemotherapy and are known to have a profound negative impact on productivity, psychosocial well-being and overall quality of life. Moderate levels of walking are known to be of benefit to the psychosocial well-being of those affected by breast cancer and for managing cognitive impairment in healthy adults, children, and the elderly. The purpose of this study is to investigate the effects of a home-based, self-managed, moderate intensity walking intervention on subjective and objective cognitive functioning in breast cancer patients undergoing chemotherapy.

METHODS

A home-based, self-managed intervention that consisted of moderate levels of walking was compared to usual care among breast cancer patients treated with chemotherapy in a randomised controlled trial. Outcome measures included changes in subjective (CFQ) and objectively detected cognitive functioning (Stroop, SART and two subscales from the WAIS- Digit Span and Block Design). Fifty participants were randomised to either the intervention group (n = 25), who completed 12 weeks of moderate intensity walking, or to the control group (n = 25) mid-way through chemotherapy.

RESULTS

Compared with the control group, the self-managed walking intervention had positive effects on perceived cognitive function but not on sustained attention, executive function, memory or visual spatial skills when assessed objectively using neuropsychological measures.

CONCLUSION

This home-based, self-managed intervention is beneficial for protecting against perceived cognitive decline in breast cancer patients treated with chemotherapy. There is a need for further research to objectively assess cognitive decline within this population with larger sample sizes of patients.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN50709297.

Cisplatin treatment induces attention deficits and impairs synaptic integrity in the prefrontal cortex in mice

Patients treated for cancer frequently experience chemobrain, characterized by impaired memory and reduced attention. These deficits often persist after treatment, and no preventive or curative interventions exist. In mice, we assessed the effect of cisplatin chemotherapy on attention using the 5-choice serial reaction time task and on synaptic integrity. We also assessed the capacity of mesenchymal stem cells to normalize the characteristics of chemobrain. Mice were trained in the 5-choice serial reaction time task. After reaching advancement criteria at a 4-second stimulus time, they were treated with cisplatin followed by nasal administration of mesenchymal stem cells. Cisplatin reduced the percentage of correct responses due to an increase in omissions, indicating attention deficits. Mesenchymal stem cell treatment reversed these cisplatin-induced deficits in attention. Cisplatin also induced abnormalities in markers of synaptic integrity in the prefrontal cortex. Specifically, cisplatin decreased expression of the global presynaptic marker synaptophysin and the glutamatergic presynaptic marker vGlut2. Expression of the presynaptic GABAergic marker vGAT increased. Nasal mesenchymal stem cell administration normalized these markers of synaptic integrity. In conclusion, cisplatin induces long-lasting attention deficits that are associated with decreased synaptic integrity in the prefrontal cortex. Nasal administration of mesenchymal stem cells reversed these behavioural and structural deficits.