Prediction of Chemotherapy-Induced Peripheral Neuropathy in Patients with Lymphoma and Myeloma: the Roles of Brain-Derived Neurotropic Factor Protein Levels and A Gene Polymorphism.

BACKGROUND AND PURPOSE: Brain-derived neurotrophic factor (BDNF) is a neuronal growth factor that plays an essential role in the maintenance of the nervous system. We have evaluated the peripheral blood protein levels of BDNF and the valine-to-methionine substitution at codon 66 (Val66Met) single-nucleotide polymorphism (SNP) as potential biomarkers for the early recognition of chemotherapy-induced peripheral neuropathy (CIPN) in non-Hodgkin lymphoma and multiple myeloma patients. METHODS: CIPN was assessed in 45 patients at the diagnosis and during vincristine or bortezomib-based therapy using objective [reduced version of the Total Neuropathy Score (TNSr)] and subjective (FACT-GOG-NTx) tools. Depression was assessed using the Patient Health Questionnaire-9 (PHQ-9) questionnaire. BDNF protein levels and the Val66Met SNP were determined using ELISA and Sanger sequencing. RESULTS: The pretreatment BDNF protein level was inversely correlated with the maximum TNSr, FACT-GOG-NTx, and PHQ-9 scores in both genotypes. BDNF patients with the Val/Val genotype demonstrated significantly higher maximum FACT-GOG-NTx and PHQ-9 scores than those with the Val/Met and Met/Met genotypes (Met-BNDF carriers). Correlations between PHQ-9 and TNSr score were found only in Met-BDNF carriers, suggesting that peripheral neuropathy and depression coincide in Met-BDNF carriers. CONCLUSIONS: Determining the BDNF protein levels before initiating chemotherapy might be a useful tool for CIPN risk assessment and preemptive dose modification. The present data should be validated in larger studies that include other neurotoxic agents.

BDNF Val66Met is Associated with Pre-existing but not with Paclitaxel-induced Peripheral Neuropathy in an Israeli Cohort of Breast Cancer Patients.

BACKGROUND: Brain-derived neurotrophic factor (BDNF) is a neuronal growth factor that is important for the development, maintenance, and repair of the peripheral nervous system. The BDNF gene commonly carries a single nucleotide polymorphism (Val66Met-SNP), which affects the cellular distribution and activity-dependent secretion of BDNF in neuronal cells. OBJECTIVES: To check the association between BDNF Val66Met-SNP as a predisposition that enhances the development of chemotherapy-induced peripheral neuropathy in an Israeli cohort of patients with breast cancer who were treated with paclitaxel. METHODS: Peripheral neuropathy symptoms were assessed and graded at baseline, before beginning treatment, and during the treatment protocol in 35 patients, using the reduced version of the Total Neuropathy Score (TNSr). Allelic discrimination of BDNF polymorphism was determined in the patients' peripheral blood by established polymerase chain reaction and Sanger sequencing. RESULTS: We found Val/Val in 20 patients (57.14%), Val/Met in 15 patients (42.86%), and Met/Met in none of the patients (0%). Baseline TNSr scores were higher in Met-BDNF patients compared to Val-BDNF patients. The maximal TNSr scores that developed during the follow-up in Met-BDNF patients were higher than in Val-BDNF patients. However, exclusion of patients with pre-existing peripheral neuropathy from the analysis resulted in equivalent maximal TNSr scores in Met-BDNF and Val-BDNF patients. CONCLUSIONS: These observations suggest that BDNF Val66met-SNP has no detectable effect on the peripheral neuropathy that is induced by paclitaxel. The significance of BDNF Val66Met-SNP in pre-existing peripheral neuropathy-related conditions, such as diabetes, should be further investigated.

Comparative proteomics of small cell lung carcinoma.

Small cell lung carcinoma (SCLC) is an aggressive, highly metastatic cancer with a strong tendency for chemotherapy resistance. Identification of proteins uniquely expressed in SCLC cells, can facilitate the development of new diagnostic tools, improve immunotherapy, and deepen our understanding of the underlying mechanisms of the disease. Here we describe a comparative proteomics analysis of ten SCLC cell lines and three controls lines, while searching for proteins preferentially expressed in SCLC cells as potential disease markers. Total protein extracts were compared by two-dimensional gel electrophoresis and by two-dimensional liquid chromatography resulting in the identification of 1093 proteins, 202 of which were detected only in the SCLC cells. These include proteins of different cellular functions, including cellular proliferation and known tumor antigens. Since SCLC has a neuroendocrine origin, of major interest are the identified proteins involved in nerve and brain embryonic development. These proteins are potentially valuable as both tumor markers and as antigens for immunotherapy.