Genetic polymorphisms and paclitaxel- or docetaxel-induced toxicities: A systematic review

Recent Developments of Novel Pharmacologic Therapeutics for Prevention of Chemotherapy-Induced Peripheral Neuropathy

Chemotherapy-induced peripheral neuropathy (CIPN) is a common and dose-limiting toxicity, negatively affecting both quality of life and disease outcomes. To date, there is no proven preventative strategy for CIPN. Although multiple randomized trials have evaluated a variety of pharmacologic interventions for the treatment of CIPN, only duloxetine has shown clear efficacy in a phase III study. The National Cancer Institute's Symptom Management and Health-Related Quality of Life Steering Committee has identified CIPN as a priority for translational research in cancer care. Promising advances in preclinical research have identified several novel preventative and therapeutic targets, which have the potential to transform the care of patients with this debilitating neurotoxicity. Here, we provide an overarching view of emerging strategies and therapeutic targets that are currently being evaluated in CIPN.

Developing Body-Components-Based Theranostic Nanoparticles for Targeting Ovarian Cancer

Ovarian cancer mortality is the highest among gynecologic malignancies. Hence, the major challenges are early diagnosis and efficient targeted therapy. Herein, we devised model theranostic nanoparticles (NPs) for combined diagnostics and delivery of chemotherapeutics, targeted to ovarian cancer cells. These NPs were made of natural biocompatible and biodegradable body components: hyaluronic acid (HA) and serum albumin (SA). The hydrophilic HA served as the targeting ligand for cancer cells overexpressing CD44, the HA receptor. SA, the natural carrier of various ligands through the blood, served as the hydrophobic block of the self-assembling block copolymeric Maillard-conjugates. We show the successful construction of fluorescently-labeled SA-HA conjugate-based theranostic NPs, their loading with paclitaxel (PTX) (association constant (8.6 ± 0.8) × 103 M-1, maximal loading capacity of 4:1 PTX:BSA, and 96% encapsulation efficiency), selective internalization and cytotoxicity to CD44-overexpressing ovarian cancer cells (IC50: 26.4 ± 2.3 nM, compared to 115.0 ± 17.4 of free PTX, and to 58.6 ± 19.7 nM for CD44-lacking cognate ovarian cancer cells). Fluorescein isothiocyanate (FITC) was used for in vitro imaging, whereas long wavelength fluorophores or other suitable tracers would be used for future in vivo diagnostic imaging. Collectively, our findings demonstrate that fluorescent HA-SA NPs harboring a cytotoxic drug cargo can specifically target, label CD44-expressing ovarian cancer cells and efficiently eradicate them.

Reproducibility of pharmacogenetics findings for paclitaxel in a heterogeneous population of patients with lung cancer

Pharmacogenetics studies have identified several allelic variants with the potential to reduce toxicity and improve treatment outcome. The present study was designed to determine if such findings are reproducible in a heterogenous population of patients with lung cancer undergoing therapy with paclitaxel. We designed a prospective multi-institutional study that recruited n = 103 patients receiving paclitaxel therapy with a 5-year follow up. All patients were genotyped using the Drug Metabolizing Enzymes and Transporters (DMET) platform, which ascertains 1931 genotypes in 235 genes. Progression-free survival (PFS) of paclitaxel therapy and clinically-significant paclitaxel toxicities were classified and compared according to genotype. Initial screening revealed eleven variants that are associated with PFS. Of these, seven variants in ABCB11 (rs4148768), ABCC3 (rs1051640), ABCG1 (rs1541290), CYP8B1 (rs735320), NR3C1 (rs6169), FMO6P (rs7889839), and GSTM3 (rs7483) were associated with paclitaxel PFS in a multivariate analysis accounting for clinical covariates. Multivariate analysis revealed four SNPs in VKORC1 (rs2884737), SLC22A14 (rs4679028), GSTA2 (rs6577), and DCK (rs4643786) were associated with paclitaxel toxicities. With the exception of a variant in VKORC1, the present study did not find the same genetic outcome associations of other published research on pharmacogenetics variants that affect paclitaxel outcomes. This finding suggests that prior pharmacogenomics research findings may not be reproduced in the most frequently-diagnosed malignancy, lung cancer.

Auriculasin sensitizes primary prostate cancer cells to TRAIL-mediated apoptosis through up-regulation of the DR5-dependent pathway

Primary prostate cancer cells frequently develop resistance toward chemotherapy as well as most chemotherapeutics have been reported to induce undesirable cytotoxicity in normal cells. In this study, we performed sensitizing activity analysis of auriculasin (AC) to tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) in RC-58T/h/SA#4 primary prostate cancer cells without significant cytotoxicity in RWPE-1 prostate epithelial cells. Combined treatment with AC and TRAIL at optimal concentrations resulted in tumor-specific apoptotic cell death in RC-58T/h/SA#4 cells, characterized by DNA fragmentation, accumulation of apoptotic cell population, and nuclear condensation. Compared to single treatment with AC or TRAIL, co-treatment with AC and TRAIL significantly increased expression of Bax, cleaved PARP, AIF, endo G, and cytochrome c but decreased expression of phosphorylation of AKT and mammalian target of rapamycin (mTOR), phosphoinositide 3-kinase (PI3K), Bcl-2 and caspases-9, -8, -3, and -10. The sensitizing effect of AC to TRAIL was well correlated with inhibition of death receptor 5 (DR5) CHOP, and p53 expression. Moreover, pre-treatment with a chimeric blocking antibody for DR5 effectively reduced AC-TRAIL-induced cell death and apoptosis-related protein expression. These results suggest that non-toxic concentrations of AC sensitize TRAIL-resistant primary prostate cancer cells to TRAIL-mediated apoptosis via up-regulation of DR5 and downstream signaling pathways.

Docetaxel-loaded human serum albumin (HSA) nanoparticles: synthesis, characterization, and evaluation

Background

Docetaxel (DTX) is an anticancer drug that is currently formulated with polysorbate 80 and ethanol (50:50, v/v) in clinical use. Unfortunately, this formulation causes hypersensitivity reactions, leading to severe side-effects, which have been primarily attributed to polysorbate 80.

Methods

In this study, a DTX-loaded human serum albumin (HSA) nanoparticle (DTX-NP) was designed to overcome the hypersensitivity reactions that are induced by polysorbate 80. The methods of preparing the DTX-NPs have been optimized based on factors including the drug-to-HSA weight ratio, the duration of HSA incubation, and the choice of using a stabilizer. Synthesized DTX-NPs were characterized with regard to their particle diameters, drug loading capacities, and drug release kinetics. The morphology of the DTX-NPs was observed via scanning electron microscopy (SEM) and the successful preparation of DTX-NPs was confirmed via differential scanning calorimetry (DSC). The cytotoxicity and cellular uptake of DTX-NPs were investigated in the non-small cell lung cancer cell line A549 and the maximum tolerated dose (MTD) of DTX-NPs was evaluated via investigations with BALB/c mice.

Results

The study showed that the loading capacity and the encapsulation efficiency of DTX-NPs prepared under the optimal conditions was 11.2 wt% and 63.1 wt%, respectively and the mean diameter was less than 200 nm, resulting in higher permeability and controlled release. Similar cytotoxicity against A549 cells was exhibited by the DTX-NPs in comparison to DTX alone while higher maximum tolerated dose (MTD) with the DTX-NPs (75 mg/kg) than with DTX (30 mg/kg) was demonstrated in mice, suggesting that the DTX-NPs prepared with HSA yielded similar anti-tumor activity but were accompanied by less systemic toxicity than solvent formulated DTX.

Conclusions

DTX-NPs warrant further investigation and are promising candidates for clinical applications.

Investigation of chemotherapy-induced brain structural alterations in breast cancer patients with generalized q-sampling MRI and graph theoretical analysis

BACKGROUND

Breast neoplasms are the most common cancer among women in Taiwan. Cognitive deficits are common complications of breast cancer survivors treated with chemotherapy. The most frequently observed disorders involve executive function and memory impairment. With improvements in tumor intervention and the consequent increase in the number of cancer survivors, the quality of life of patients has become an important issue. We are interested in the early effects of chemotherapy on the brain structures of patients. In addition, generalized q-sampling imaging (GQI), a wide range of q-space datasets for a more accurate and sophisticated diffusion MR approach, was first used in this topic.

METHODS

As diffusion tensor imaging (DTI) is associated with restrictions in the resolution of crossing fibers, we attempted to use GQI, which can overcome these difficulties and is advantageous over DTI for tractography of the crossing fibers. This cross-sectional study included two groups: breast cancer survivors who had completed their chemotherapy (n = 19) and healthy controls (n = 20). All participants underwent diffusion MRI exams and neuropsychological assessments. We included four parts in our image analysis, i.e., voxel-based statistical analysis, multiple regression analysis, graph theoretical analysis and network-based statistical analysis.

RESULTS

The results from the voxel-based statistical analysis showed significantly lower GFA and NQA values in the breast cancer group than those in the control group. We found significant positive correlations between the FACT-Cog and GQI indices. In the graph theoretical analysis, the breast cancer group demonstrated significantly longer characteristic path length. Adjuvant chemotherapy affected the integrity of white matter and resulted in poor cognitive performance, as indicated by the correlations between the neuropsychological assessment scales and the GQI indices. In addition, it was found that the characteristic path lengths in the breast cancer group increased, indicating that the brain network integration became worse.

CONCLUSIONS

Our study demonstrated alterations in structural brain networks and associated neuropsychological deficits among breast cancer survivors.

Tolerance, Variability and Pharmacokinetics of Albumin-Bound Paclitaxel in Chinese Breast Cancer Patients

Objective: The aim of this study was to explore the tolerance, variability, and pharmacokinetics (PK) of albumin-bound paclitaxel (QL, HR, ZDTQ) among Chinese breast cancer patients.

Methods: Three randomized, open-label, two-period crossover bioequivalence studies were conducted with albumin-bound paclitaxel. Each subject received a single dose of 260 mg/m² albumin-bound paclitaxel [sponsor 1 (QL, light food), sponsor 2 (HR, fasting), sponsor 3 (ZDTQ, light food); test] or Abraxane® (reference) and was monitored for 72 h. Serum concentrations of total paclitaxel and unbound paclitaxel were measured using liquid chromatography/mass spectrometry (LC/MS), and appropriate pharmacokinetic parameters were determined by non-compartmental methods. Safety assessments included adverse events, hematology and biochemistry tests.

Results: The bioequivalence analyses of the QL, HR, and ZDTQ products included 24, 23, and 24 patients, respectively. The mean t_1/2 was 20.61–27.31 h for total paclitaxel. Food intake did not affect the pharmacokinetics of paclitaxel. From the comparison of total paclitaxel and unbound paclitaxel, the 90% confidence intervals (CIs) for the ratios of C_max, AUC_0−t, and AUC_0−∞ were within 80.00–125.00%. The intra-subject variability ranged from 6.4–11% to 9.85–15.87% for total paclitaxel and unbound paclitaxel, respectively. Almost all subjects in the test and Abraxane® (reference) groups experienced mild or moderate adverse events. No fatal AEs or study drug injection site reactions related to these drugs were observed.

Conclusion: Albumin-bound paclitaxel (QL, HR or ZDTQ; test products) showed bioequivalence to Abraxane® (reference) with lower intra-subject variability, which was less than 16% in all cases, and was well-tolerated in Chinese breast cancer patients. Twenty-two patients are enough for an albumin-bound paclitaxel bioequivalence study.

Inhibition of Prostate Cancer DU-145 Cells Proliferation by Anthopleura anjunae Oligopeptide (YVPGP) via PI3K/AKT/mTOR Signaling Pathway

We investigated the antitumor mechanism of Anthopleura anjunae oligopeptide (AAP-H, YVPGP) in prostate cancer DU-145 cells in vitro and in vivo. Results indicated that AAP-H was nontoxic and exhibited antitumor activities. Cell cycle analysis indicated that AAP-H may arrest DU-145 cells in the S phase. The role of the phosphatidylinositol 3-kinase/protein kinase B/mammalian rapamycin target protein (PI3K/AKT/mTOR) signaling pathway in the antitumor mechanism of APP-H was investigated. Results showed that AAP-H treatment led to dose-dependent reduction in the levels of p-AKT (Ser473), p-PI3K (p85), and p-mTOR (Ser2448), whereas t-AKT and t-PI3K levels remained unaltered compared to the untreated DU-145 cells. Inhibition of PI3K/AKT/mTOR signaling pathway in the DU-145 cells by employing inhibitor LY294002 (10 μM) or rapamycin (20 nM) effectively attenuated AAP-H-induced phosphorylation of AKT and mTOR. At the same time, inhibitor addition further elevated AAP-H-induced cleaved-caspase-3 levels. Furthermore, the effect of AAP-H on tumor growth and the role of the PI3K/AKT/mTOR signaling pathway in nude mouse model were also investigated. Immunohistochemical analysis showed that activated AKT, PI3K, and mTOR levels were reduced in DU-145 xenografts. Western blotting showed that AAP-H treatment resulted in dose-dependent reduction in p-AKT (Ser473), p-PI3K (p85), and p-mTOR (Ser2448) levels, whereas t-AKT and t-PI3K levels remained unaltered. Similarly, Bcl-xL levels decreased, whereas that of Bax increased after AAP-H treatment. AAP-H also increased initiator (caspase 8 and 9) and executor caspase (caspase 3 and 7) levels. Therefore, the antitumor mechanism of APP-H on DU-145 cells may involve regulation of the PI3K/AKT/mTOR signaling pathway, which eventually promotes apoptosis via mitochondrial and death receptor pathways. Thus, the hydrophobic oligopeptide (YVPGP) can be developed as an adjuvant for the prevention or treatment of prostate cancer in the future.

Pharmacogenetic impact of docetaxel on neoadjuvant treatment of breast cancer patients

AIM

This study aimed to investigate the effect of CYP3A4 and CYP3A5 genotypes on clinical outcomes of docetaxel treatment.

PATIENTS & METHODS

In the PROMIX trial, 150 breast cancer patients received docetaxel preoperatively. CYP3A4 and CYP3A5 genotype combinations were transformed into total CYP 3A phenotypes.

RESULTS

Seven patients were characterized as poor metabolizer (PM), 22 patients as extensive metabolizer and 121 patients as intermediate metabolizer. The frequency of grade 3/grade 4 adverse events was higher in the PM group (p = 0.002). One PM subject who basically lacked enzyme activity died from typhlitis. Total 45 recurrences were reported after a median of 5-year follow-up; none of these was PM.

CONCLUSION

The allelic variants CYP3A4*22 and CYP3A5*3 contribute to the interpatient variations of docetaxel.

Licochalcone C induced apoptosis in human oral squamous cell carcinoma cells by regulation of the JAK2/STAT3 signaling pathway

Oral cancer is of an aggressive malignancy that arises on oral cavity and lip, 90% of cancers histologically originated in the squamous cells. Licochalcone (LC)C has been known as natural phenolic chalconoid substances, and its origin is the root of Glycyrrhiza glabra or Glycyrrhiza inflata. LCC inhibited oral squamous cell carcinoma (OSCC) cell viability, mitochondrial function, and anchorage-independent growth in a dose-dependent manner. To investigate the ability of LCC to target Janus kinase 2 (JAK2), we performed pull-down binding assay, kinase assay, and docking simulation. The molecular docking studies were performed between JAK2 and the potent inhibitor LCC. It was shown that LCC tightly interacted with ATP-binding site of JAK2. In addition, LCC inhibited the JAK2/signal transducer and activator of transcription 3 pathway, upregulated p21, and downregulated Bcl-2, Mcl-1, and Survivin, while it disrupted mitochondrial membrane potential and subsequently caused cytochrome c release with activation of multi-caspase, eventually leading to apoptosis in HN22 and HSC4 cells. LCC elevated the protein levels of Bax, cleaved Bid and PARP, and increased Apaf-1, and this effect was reversed by LCC treatment. Our results demonstrated that treatment of OSCC cells with LCC induced the death receptor (DR)4 and DR5 expression level with the generation of reactive oxygen species and the upregulation of CHOP protein expression. Taken together, these results could provide the basis for clinical application as a new therapeutic strategy in the treatment of oral cancer.

GSTP1 rs1695 is associated with both hematological toxicity and prognosis of ovarian cancer treated with paclitaxel plus carboplatin combination chemotherapy: a comprehensive analysis using targeted resequencing of 100 pharmacogenes

Purpose

To find genetic variants that predicted toxicity and/or efficacy of paclitaxel plus carboplatin combination therapy (TC therapy).

Patients and methods

In a retrospective case-control study, we analyzed 320 patients who had received TC therapy for gynecological cancers (ovarian, fallopian tube, peritoneal, uterine, and cervical cancers) and collected their germline DNA. We performed a comprehensive pharmacogenomic analysis using a targeted resequencing panel of 100 pharmacogenes. For 1,013 variants passing QC, case-control association studies and survival analyses were conducted.

Results

GSTP1 rs1695 showed the smallest p value for hematotoxicity association, and the ¹⁰⁵Ile wild type allele had a significantly higher risk of severe hematotoxicity (neutropenia G4, thrombocytopenia ≥ G3 and anemia ≥ G3) than the ¹⁰⁵Val allele (p=0.00034, odds ratio=5.71 (95% confidence interval:1.77-18.44)). Next, we assessed 5-year progression-free survival (PFS) and overall survival (OS) in 56 advanced ovarian cancer patients who received tri-weekly TC as a first-line chemotherapy. Patients with the ¹⁰⁵Ile/¹⁰⁵Ile genotype showed significantly better PFS (p=0.00070) and OS (p=0.0012) than those with the ¹⁰⁵Ile/¹⁰⁵Val or ¹⁰⁵Val/¹⁰⁵Val genotype.

Conclusion

Our study indicates that the GSTP1 rs1695 ¹⁰⁵Ile/¹⁰⁵Ile genotype is associated with both severe hematotoxicity and high efficacy of TC therapy, identifying a possible prognostic indicator for patients with TC therapy.

Endoplasmic reticulum stress-mediated autophagy protects against β,β-dimethylacrylshikonin-induced apoptosis in lung adenocarcinoma cells

β,β‐Dimethylacrylshikonin (DMAS) is an anti‐cancer compound extracted from the roots of Lithospermum erythrorhizon. The present study aims to investigate the effects of DMAS on human lung adenocarcinoma cells in vitro and explore the mechanisms of its anti‐cancer action. We showed that DMAS markedly inhibited cell viability in a dose‐ and time‐dependent way, and induced apoptosis as well as autophagy in human lung adenocarcinoma cells. Furthermore, we found that DMAS stimulated endoplasmic reticulum stress and mediated autophagy through the PERK‐eIF2α‐ATF4‐CHOP and IRE1‐TRAF2‐JNK axes of the unfolded protein response in human lung adenocarcinoma cells. We also showed that the autophagy induced by DMAS played a prosurvival role in human lung adenocarcinoma cells and attenuated the apoptotic cascade. Collectively, combined treatment of DMAS and pharmacological autophagy inhibitors could offer an effective therapeutic strategy for lung adenocarcinoma treatment.

SNPs in predicting clinical efficacy and toxicity of chemotherapy: walking through the quicksand

In the "precision medicine" era, chemotherapy still remains the backbone for the treatment of many cancers, but no affordable predictors of response to the chemodrugs are available in clinical practice. Single nucleotide polymorphisms (SNPs) are gene sequence variations occurring in more than 1% of the full population, and account for approximately 80% of inter-individual genomic heterogeneity. A number of studies have investigated the predictive role of SNPs of genes enrolled in both pharmacodynamics and pharmacokinetics of chemotherapeutics, but the clinical implementation of related results has been modest so far. Among the examined germline polymorphic variants, several SNPs of dihydropyrimidine dehydrogenase (DPYD) and uridine diphosphate glucuronosyltransferases (UGT) have shown a robust role as predictors of toxicity following fluoropyrimidine- and/or irinotecan-based treatments respectively, and a few guidelines are mandatory in their detection before therapy initiation. Contrasting results, however, have been reported on the capability of variants of other genes as MTHFR, TYMS, ERCC1, XRCC1, GSTP1, CYP3A4/3A5 and ABCB1, in predicting either therapy efficacy or toxicity in patients undergoing treatment with pyrimidine antimetabolites, platinum derivatives, irinotecan and taxanes. While formal recommendations for routine testing of these SNPs cannot be drawn at this moment, therapeutic decisions may indeed benefit of germline genomic information, when available. Here, we summarize the clinical impact of germline genomic variants on the efficacy and toxicity of major chemodrugs, with the aim to facilitate the therapeutic expectance of clinicians in the odiern quicksand field of complex molecular biology concepts and controversial trial data interpretation.

FOXM1 contributes to taxane resistance by regulating UHRF1-controlled cancer cell stemness

Therapy-induced expansion of cancer stem cells (CSCs) has been identified as one of the most critical factors contributing to therapeutic resistance, but the mechanisms of this adaptation are not fully understood. UHRF1 is a key epigenetic regulator responsible for therapeutic resistance, and controls the self-renewal of stem cells. In the present study, taxane-resistant cancer cells were established and stem-like cancer cells were expanded. UHRF1 was overexpressed in the taxane-resistant cancer cells, which maintained CSC characteristics. UHRF1 depletion overcame taxane resistance in vitro and in vivo. Additionally, FOXM1 has been reported to play a role in therapeutic resistance and the self-renewal of CSCs. FOXM1 and UHRF1 are highly correlated in prostate cancer tissues and cells, FOXM1 regulates CSCs by regulating uhrf1 gene transcription in an E2F-independent manner, and FOXM1 protein directly binds to the FKH motifs at the uhrf1 gene promoter. This present study clarified a novel mechanism by which FOXM1 controls CSCs and taxane resistance through a UHRF1-mediated signaling pathway, and validated FOXM1 and UHRF1 as two potential therapeutic targets to overcome taxane resistance.

ABCB1 Variation Affects Myelosuppression, Progression-free Survival and Overall Survival in Paclitaxel/Carboplatin-treated Ovarian Cancer Patients

The standard chemotherapy for ovarian cancer is paclitaxel/carboplatin. Patients often exhibit myelosuppressive toxicity, and the treatment response varies considerably. In this study, we investigated the previously reported SNPs 1199G>A (rs2229109), 1236C>T (rs1128503), 2677G>T/A (rs2032582), 3435C>T (rs1045642) in ABCB1, and 1196A>G (rs10509681) in CYP2C8 and their association with treatment-induced myelosuppression, progression-free survival (PFS) and overall survival (OS). From the phase III study, OAS-07OVA, 525 patients (All) treated with carboplatin and paclitaxel administered as Paclical (Arm A, n = 260) or Taxol^® (Arm B, n = 265) were included and genotyped using pyrosequencing. Genotype associations with myelosuppression, PFS and OS were investigated using anova, Kaplan-Meier analysis and Cox proportional hazard models. The most prominent finding was for the ABCB1 variant 3435TT, which was significantly associated with increased PFS in All (hazard ratio (HR) = 0.623), in Arm A (HR = 0.590) and in Arm B (HR = 0.627), as well as increased OS in All (HR = 0.443) and in Arm A (HR = 0.372) compared to the wild-type, 3435CC. For toxicity, the most interesting finding concerned the haplotype, including 1236TT, 2677TT and 3435TT, which was associated with higher neutrophil values in Arm B (p = 0.039) and less neutrophil decrease in All (p = 0.048) and in Arm B (p = 0.021). It is noteworthy that the results varied depending on the treatment arm which indicates that the effects of ABCB1 variants vary with the treatment regimen. Our results reflect the contradictory results of previous studies, confirming that small variations in the composition of treatment regimens and patient populations may influence the interpretation of SNPs effects on treatment outcome.

Chemoresistance to Cancer Treatment: Benzo-α-Pyrene as Friend or Foe?

Background: Environmental pollution such as exposure to pro-carcinogens including benzo-α-pyrene is becoming a major problem globally. Moreover, the effects of benzo-α-pyrene (BaP) on drug pharmacokinetics, pharmacodynamics, and drug resistance warrant further investigation, especially in cancer outpatient chemotherapy where exposure to environmental pollutants might occur. Method: We report here on the effects of benzo-α-pyrene on esophageal cancer cells in vitro, alone, or in combination with chemotherapeutic drugs cisplatin, 5-flurouracil, or paclitaxel. As the study endpoints, we employed expression of proteins involved in cell proliferation, drug metabolism, apoptosis, cell cycle analysis, colony formation, migration, and signaling cascades in the WHCO1 esophageal cancer cell line after 24 h of treatment. Results: Benzo-α-pyrene had no significant effect on WHCO1 cancer cell proliferation but reversed the effect of chemotherapeutic drugs by reducing drug-induced cell death and apoptosis by 30−40% compared to drug-treated cells. The three drugs significantly reduced WHCO1 cell migration by 40−50% compared to control and BaP-treated cells. Combined exposure to drugs was associated with significantly increased apoptosis and reduced colony formation. Evaluation of survival signaling cascades showed that although the MEK-ERK and Akt pathways were activated in the presence of drugs, BaP was a stronger activator of the MEK-ERK and Akt pathways than the drugs. Conclusion: The present study suggest that BaP can reverse the effects of drugs on cancer cells via the activation of survival signaling pathways and upregulation of anti-apoptotic proteins such as Bcl-2 and Bcl-xL. Our data show that BaP contribute to the development of chemoresistant cancer cells.

Perturbing mitosis for anti-cancer therapy: is cell death the only answer?

Interfering with mitosis for cancer treatment is an old concept that has proven highly successful in the clinics. Microtubule poisons are used to treat patients with different types of blood or solid cancer since more than 20 years, but how these drugs achieve clinical response is still unclear. Arresting cells in mitosis can promote their demise, at least in a petri dish. Yet, at the molecular level, this type of cell death is poorly defined and cancer cells often find ways to escape. The signaling pathways activated can lead to mitotic slippage, cell death, or senescence. Therefore, any attempt to unravel the mechanistic action of microtubule poisons will have to investigate aspects of cell cycle control, cell death initiation in mitosis and after slippage, at single-cell resolution. Here, we discuss possible mechanisms and signaling pathways controlling cell death in mitosis or after escape from mitotic arrest, as well as secondary consequences of mitotic errors, particularly sterile inflammation, and finally address the question how clinical efficacy of anti-mitotic drugs may come about and could be improved.

Proinflammatory Factors Mediate Paclitaxel-Induced Impairment of Learning and Memory

The chemotherapeutic agent paclitaxel is widely used for cancer treatment. Paclitaxel treatment impairs learning and memory function, a side effect that reduces the quality of life of cancer survivors. However, the neural mechanisms underlying paclitaxel-induced impairment of learning and memory remain unclear. Paclitaxel treatment leads to proinflammatory factor release and neuronal apoptosis. Thus, we hypothesized that paclitaxel impairs learning and memory function through proinflammatory factor-induced neuronal apoptosis. Neuronal apoptosis was assessed by TUNEL assay in the hippocampus. Protein expression levels of tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) in the hippocampus tissue were analyzed by Western blot assay. Spatial learning and memory function were determined by using the Morris water maze (MWM) test. Paclitaxel treatment significantly increased the escape latencies and decreased the number of crossing in the MWM test. Furthermore, paclitaxel significantly increased the number of TUNEL-positive neurons in the hippocampus. Also, paclitaxel treatment increased the expression levels of TNF-α and IL-1β in the hippocampus tissue. In addition, the TNF-α synthesis inhibitor thalidomide significantly attenuated the number of paclitaxel-induced TUNEL-positive neurons in the hippocampus and restored the impaired spatial learning and memory function in paclitaxel-treated rats. These data suggest that TNF-α is critically involved in the paclitaxel-induced impairment of learning and memory function.

Genotoxicity assessment of a selected cytostatic drug mixture in human lymphocytes: A study based on concentrations relevant for occupational exposure

Cytostatic drugs are highly cytotoxic agents used in cancer treatment and although their benefit is unquestionable, they have been recognized as hazardous to healthcare professionals in occupational settings. In a working environment, simultaneous exposure to cytostatics may occur creating a higher risk than that of a single substance. Hence, the present study evaluated the combined cyto/genotoxicity of a mixture of selected cytostatics with different mechanisms of action (MoA; 5-fluorouracil, cyclophosphamide and paclitaxel) towards human lymphocytes in vitro at a concentration range relevant for occupational as well as environmental exposure. The results suggest that the selected cytostatic drug mixture is potentially cyto/genotoxic and that it can induce cell and genome damage even at low concentrations. This indicates not only that such mixture may pose a risk to cell and genome integrity, but also that single compound toxicity data are not sufficient for the prediction of toxicity in a complex working environment. The presence of drugs in different amounts and with different MoA suggests the need to study the relationship between the presence of genotoxic components in the mixture and the resulting effects, taking into account the MoA of each component by itself. Therefore, this study provides new data sets necessary for scientifically-based risk assessments of cytostatic drug mixtures in occupational as well as environmental settings.

Human mesenchymal stem cells lose their functional properties after paclitaxel treatment

Mesenchymal stem cells (MSCs) are an integral part of the bone marrow niche and aid in the protection, regeneration and proliferation of hematopoietic stem cells after exposure to myelotoxic taxane anti-cancer agents, but the influence of taxane compounds on MSCs themselves remains incompletely understood. Here, we show that bone marrow-derived MSCs are highly sensitive even to low concentrations of the prototypical taxane compound paclitaxel. While MSCs remained metabolically viable, they were strongly impaired regarding both their proliferation and their functional capabilities after exposure to paclitaxel. Paclitaxel treatment resulted in reduced cell migration, delays in cellular adhesion and significant dose-dependent inhibition of the stem cells’ characteristic multi-lineage differentiation potential. Cellular morphology and expression of the defining surface markers remained largely unaltered. Paclitaxel only marginally increased apoptosis in MSCs, but strongly induced premature senescence in these stem cells, thereby explaining the preservation of the metabolic activity of functionally inactivated MSCs. The reported sensitivity of MSC function to paclitaxel treatment may help to explain the severe bone marrow toxicities commonly caused by taxane-based anti-cancer treatments.

Auriculasin-induced ROS causes prostate cancer cell death via induction of apoptosis

Recent studies have demonstrated that natural agents targeting the accumulation of reactive oxygen species (ROS) that selectively kill, leaving normal cells undamaged, can suppress prostate cancer. Here, we show that auriculasin, derived from Flemingia philippinensis, induces significant cell death and apoptosis via ROS generation in prostate cancer cells. Auriculasin treatment resulted in selective apoptotic cell death in LNCaP prostate cancer cells, characterized by DNA fragmentation, accumulation of sub-G1 cell population, cleavage of poly (ADP-ribose) polymerase (PARP), regulation of Bax/Bcl-2 ratio, increase of cytosolic apoptosis-inducing factor (AIF) and endonuclease G (EndoG), in addition to inhibiting tumor growth in a xenograft mouse model. Interestingly, auriculasin-induced apoptosis did not result in caspase-3, -8, and -9 activations. We found that auriculasin treatment decreased phosphorylation of AKT/mTOR/p70s6k in a dose- and time-dependent manner. Further, cellular ROS levels increased in LNCaP cells treated with auriculasin and blocking ROS accumulation with ROS scavengers resulted in inhibition of auriculasin-induced PARP cleavage, AIF increase, upregulation of Bax/Bcl-2 ratio, and decrease in AKT/mTOR phosphorylation. Taken together, these data suggest that auriculasin targets ROS-mediated caspase-independent pathways and suppresses PI3K/AKT/mTOR signaling, which leads to apoptosis and decreased tumor growth.

Role of GABAB receptors and p38MAPK/NF-κB pathway in paclitaxel-induced apoptosis of hippocampal neurons

CONTEXT

The effects of the anticancer drug paclitaxel on learning and memory are rarely studied.

OBJECTIVE

This study investigated changes in GABAB receptor expression during paclitaxel-induced apoptosis of hippocampal neurons and the role of the p38MAPK/NF-κB pathway in this process.

MATERIALS AND METHODS

Hippocampal neurons isolated from neonatal Sprague-Dawley rats were divided into six groups: Control (C), SB (10 µL of 10-µmol/L SB203580), SN (53 µg/mL SN50), N (1 µmol/L paclitaxel), SB + N (10 µmol/L SB203580 + 1 µmol/L paclitaxel) and SN + N (53 µg/mL SN50 + 1 µmol/L paclitaxel). Cells in different groups were treated with corresponding agents for 24 h at 37 °C. The apoptosis rate and protein levels of GABAB1 receptors and NF-κB p65 were evaluated. Rat models of neuropathic pain was induced by paclitaxel and were divided into four groups such as N, B + N, SN + N and SN + B + N groups. Rats in the N group received intrathecal injections of normal saline solution. Rats in the B + N group received intrathecal injections of 10 μL baclofen (0.05 μg/μL). Rats in the SN + N and SN + B + N groups received intrathecal injections of SN50 and SN50 plus baclofen, respectively. Spatial learning and memory were evaluated in rat models based on the escape latency and the number of crossings over the platform and protein levels of GABAB1 receptors, NF-κB, IL-1β and TNFα were measured by immunohistochemistry assay and western blot.

RESULTS

The neuronal apoptosis rate was significantly increased in N (49.16 ± 3.12)%, SB + N (31.18 ± 3.02)% and SN + N (28.47 ± 3.75)% groups, accompanied by increased levels of GABAB1 receptors and NF-κB p65 (p < 0.05). The paclitaxel-treated rats demonstrated significantly increased latency (24.32 ± 2.94)s and decreased the crossings number (3.14 ± 0.63) after 15 d in the Morris water maze (p < 0.05). Immunohistochemistry assay showed that compared with the N group (GABAB1:9.0 ± 1.6, NF-κB p65:29.6 ± 2.4, IL-1β: 30.4 ± 3.4, TNFα: 31.0 ± 3.4), B + N, SN + N and SN + B + N groups evidently increased levels of GABAB1 receptor (B + N:SN + N:SN + B + N = 19.4 ± 2.1:20.8 ± 1.9:28.0 ± 1.9) but significantly decreased levels of NF-κB p65 (B + N:SN + N:SN + B + N = 21.2 ± 1.5:18.6 ± 2.1:12.6 ± 1.5), IL-1β (B + N:SN + N:SN + B + N = 22.0 ± 1.0:19.6 ± 1.8:14.6 ± 1.5) and TNF α (B + N:SN + N:SN + B + N = 23.0 ± 1.6:22.2 ± 0.8:16.6 ± 1.7). Similar findings were found in western blot analysis.

DISCUSSIONS AND CONCLUSIONS

Paclitaxel may reduce cognitive function in rats through the p38MAPK/NF-κB pathway and GABAB1 receptors.

Assessment of Pharmacogenomic Panel Assay for Prediction of Taxane Toxicities: Preliminary Results

Backbone: Paclitaxel and docetaxel are the primary taxane anticancer drugs regularly used to treat, breast, gastric, ovarian, head/neck, lung, and genitourinary neoplasm. Suspension of taxane treatments compromising patient benefits is more frequently caused by peripheral neuropathy and allergy, than to tumor progression. Several strategies for preventing toxicity have been investigated so far. Recently, findings on the genetic variants associated with toxicity and resistance to taxane-based chemotherapy have been reported.

Methods: An extensive panel of five polymorphisms on four candidate genes (ABCB1, CYP2C8^*3, CYP3A4^*1B, XRCC3), previously validated as significant markers related to paclitaxel and Docetaxel toxicity, are analyzed and discussed. We genotyped 76 cancer patients, and 35 of them received paclitaxel or docetaxel-based therapy. What is more, an early outline evaluation of the genotyping costs and benefit was assessed.

Results: Out of 35 patients treated with a taxane, six (17.1%) had adverse neuropathy events. Pharmacogenomics analysis showed no correlation between candidate gene polymorphisms and toxicity, except for the XRCC3 AG+GG allele [OR 2.61 (95% CI: 0.91–7.61)] which showed a weak significant trend of risk of neurotoxicities vs. the AG allele [OR 1.52 (95% CI: 0.51–4.91)] P = 0.03.

Summary: Based on our experimental results and data from the literature, we propose a useful and low-cost genotyping panel assay for the prevention of toxicity in patients undergoing taxane-based therapy. With the individual pharmacogenomics profile, clinicians will have additional information to plan the better treatment for their patients to minimize toxicity and maximize benefits, including determining cost-effectiveness for national healthcare sustainability.

Critically short telomeres and toxicity of chemotherapy in early breast cancer

Cumulative toxicity from weekly paclitaxel (myalgia, peripheral neuropathy, fatigue) compromises long-term administration. Preclinical data suggest that the burden of critically short telomeres (< 3 kilobases, CSTs), but not average telomere length by itself, accounts for limited tissue renewal and turnover capacity. The impact of this parameter (which can be modified with different therapies) in chemotherapy-derived toxicity has not been studied.

Blood from 115 treatment-naive patients from a clinical trial in early HER2-negative breast cancer that received weekly paclitaxel (80 mg/m2 for 12 weeks) either alone or in combination with nintedanib and from 85 healthy controls was prospectively obtained and individual CSTs and average telomere lenght were determined by HT Q-FISH (high-throughput quantitative FISH). Toxicity was graded according to NCI common toxicity criteria for adverse events (NCI CTCAE V.4.0). The variable under study was “number of toxic episodes” during the 12 weeks of therapy.

The percentage of CSTs ranged from 6.5%–49.4% and was directly associated with the number of toxic events (R² = 0.333; P < 0.001). According to a linear regression model, each 18% increase in the percentage of CSTs was associated to one additional toxic episode during the paclitaxel cycles; this effect was independent of the age or treatment arm. Patients in the upper quartile (> 21.9% CSTs) had 2-fold higher number of neuropathy (P = 0.04) or fatigue (P = 0.019) episodes and >3-fold higher number of myalgia episodes (P = 0.005). The average telomere length was unrelated to the incidence of side effects.

The percentage of CSTs, but not the average telomere size, is associated with weekly paclitaxel-derived toxicity.

Adjuvant Therapy with Silibinin Improves the Efficacy of Paclitaxel and Cisplatin in MCF-7 Breast Cancer Cells

Herbal-derived medicines have introduced as sources of novel drugs due to minimum systemic side effects. Silibinin as a flavonoid compound has showed with effective chemotherapeutic effects on different cancers. Here, we investigated the impact of combination therapy of silibinin, with paclitaxel and cisplatin in inhibition of proliferation and induction of apoptosis in MCF-7 cells. Cell proliferation was assessed by MTT assay and the percentage of apoptotic cells was measured using flowcytometric assay. Understand of molecular mechanism of this combination related to apoptotic pathway were evaluated by Real Time RT-PCR assays. The IC₅₀ values for silibinin, paclitaxel and cisplatin were 160 ± 22.2 µM, 33.7 ± 4.2 nM and 3.2 ± 0.5 µM, respectively. Paclitaxel and cisplatin induced higher percentage of apoptosis in MCF-7 (P < 0.05). Treatment of cell line with combination of silibinin and paclitaxel or cisplatin showed enhanced early apoptosis 56% and 61%, respectively (P < 0.05). Gene expression patterns demonstrated a significant decrease in anti-apoptotic Bcl-2 with increase in pro-apoptotic Bax, P53, BRCA1 and ATM mRNA levels. Taken together combination therapy of breast cancer cells by applying paclitaxel or cisplatin with silibinin synergistically increases the anti-proliferative effect of single agents.

Single-nucleotide polymorphisms in the genes of CES2, CDA and enzymatic activity of CDA for prediction of the efficacy of capecitabine-containing chemotherapy in patients with metastatic breast cancer

We examined whether genetic polymorphisms (SNPs) in the capecitabine activation pathway and CDA enzymatic activity were associated with prognosis, benefit from capecitabine-containing treatment or capecitabine-related toxicities. The study population comprised 188 metastatic breast cancer patients of the ATX trial (EudraCT 2006-006058-83) randomized for first-line paclitaxel and bevacizumab with (ATX) or without capecitabine (AT). Cumulative capecitabine dose until grade ≥2 hand-foot syndrome or until first dose reduction were toxicity endpoints. We genotyped CDA c.-451C>T (rs532545), CDA c.-33delC (rs3215400) and CES2 c.-806C>G (rs11075646). CDA activity in baseline serum was measured with a spectrophotometric assay and values were analyzed using a median cut-off or as continuous variable. CDA c.-33delC was prognostic for overall survival (OS) independent of hormone receptor status. For the predictive analysis, progression-free survival benefit from ATX over AT was observed in patients with a CDA c.-33del/del or del/insC genotype, a CDA c.-451CC or CT genotype, and a CES2 c.-806CC genotype compared with their counterparts. There was a higher response rate for ATX over AT in patients with a CDA c.-451CT or TT genotype. Patients with high CDA enzymatic activity had more benefit from capecitabine, while this was marginally observed in the CDA low group. Toxicity endpoints were not associated with any candidate markers. In conclusion, CDA c.-33delC was associated with OS. Since particular SNPs in CDA and CES2 were associated with benefit from the addition of capecitabine to AT, their predictive value should be explored in a higher number of patients.

Whole exome sequencing detects variants of genes that mediate response to anticancer drugs

Certain interindividual differences affecting the efficacy of drug treatment and adverse drug reactions are caused by genetic variants, and their phenotypic effects differ among ethnic groups. In this study, we used whole exome sequencing (WES) systematically to identify germline mutations that influence the activities of drug-metabolizing enzymes, as well as that of a transporter. We analyzed DNA isolated from blood samples from 2,042 Japanese patients with diverse cancers. We identified sequence variants of CYP2B6 (rs3745274), CYP2C9 (rs1057910), CYP2C19 (rs4986893), CYP2C19 (rs4244285), TPMT (rs1142345), NAT2 (rs1799930), NAT2 (rs1799931), UGT1A1 (rs4148323), COMT (rs4680), ABCB1 (rs1045642), and CDA (rs60369023). Wider application of WES will help to determine the effects of mutations on the activities of proteins encoded by drug response genes, and the information gained will accelerate the development of personalized therapies for patients with cancer. Moreover, this knowledge may provide clues for preventing cancer before the onset of symptoms.

The FOXM1-ABCC5 axis contributes to paclitaxel resistance in nasopharyngeal carcinoma cells

Paclitaxel is clinically used as a first-line chemotherapeutic regimen for several cancer types, including head and neck cancers. However, acquired drug resistance results in the failure of therapy, metastasis and relapse. The drug efflux mediated by ATP-binding cassette (ABC) transporters and the survival signals activated by forkhead box (FOX) molecules are critical in the development of paclitaxel drug resistance. Whether FOX molecules promote paclitaxel resistance through drug efflux remains unknown. In this study, we developed several types of paclitaxel-resistant (TR) nasopharyngeal carcinoma (NPC) cells. These TR NPC cells acquired cancer stem cell (CSC) phenotypes and underwent epithelial to mesenchymal transition (EMT), and developed multidrug resistance. TR cells exhibited stronger drug efflux than parental NPC cells, leading to the reduction of intracellular drug concentrations and drug insensitivity. After screening the gene expression of ABC transporters and FOX molecules, we found that FOXM1 and ABCC5 were consistently overexpressed in the TR NPC cells and in patient tumor tissues. Further studies demonstrated that FOXM1 regulated abcc5 gene transcription by binding to the FHK consensus motifs at the promoter. The depletion of FOXM1 or ABCC5 with siRNA significantly blocked drug efflux and increased the intracellular concentrations of paclitaxel, thereby promoting paclitaxel-induced cell death. Siomycin A, a FOXM1 inhibitor, significantly enhanced in vitro cell killing by paclitaxel in drug-resistant NPC cells. This study is the first to identify the roles of FOXM1 in drug efflux and paclitaxel resistance by regulating the gene transcription of abcc5, one of the ABC transporters. Small molecular inhibitors of FOXM1 or ABCC5 have the potential to overcome paclitaxel chemoresistance in NPC patients.

Long-Term Effects, Pathophysiological Mechanisms, and Risk Factors of Chemotherapy-Induced Peripheral Neuropathies: A Comprehensive Literature Review

Neurotoxic anticancer drugs, such as platinum-based anticancer drugs, taxanes, vinca alkaloids, and proteasome/angiogenesis inhibitors are responsible for chemotherapy-induced peripheral neuropathy (CIPN). The health consequences of CIPN remain worrying as it is associated with several comorbidities and affects a specific population of patients already impacted by cancer, a strong driver for declines in older adults. The purpose of this review is to present a comprehensive overview of the long-term effects of CIPN in cancer patients and survivors. Pathophysiological mechanisms and risk factors are also presented. Neurotoxic mechanisms leading to CIPNs are not yet fully understood but involve neuronopathy and/or axonopathy, mainly associated with DNA damage, oxidative stress, mitochondria toxicity, and ion channel remodeling in the neurons of the peripheral nervous system. Classical symptoms of CIPNs are peripheral neuropathy with a “stocking and glove” distribution characterized by sensory loss, paresthesia, dysesthesia and numbness, sometimes associated with neuropathic pain in the most serious cases. Several risk factors can promote CIPN as a function of the anticancer drug considered, such as cumulative dose, treatment duration, history of neuropathy, combination of therapies and genetic polymorphisms. CIPNs are frequent in cancer patients with an overall incidence of approximately 38% (possibly up to 90% of patients treated with oxaliplatin). Finally, the long-term reversibility of these CIPNs remain questionable, notably in the case of platinum-based anticancer drugs and taxanes, for which CIPN may last several years after the end of anticancer chemotherapies. These long-term effects are associated with comorbidities such as depression, insomnia, falls and decreases of health-related quality of life in cancer patients and survivors. However, it is noteworthy that these long-term effects remain poorly studied, and only limited data are available such as in the case of bortezomib and thalidomide-induced peripheral neuropathy.

Pharmacogenomics of second-line drugs used for treatment of unresponsive or relapsed osteosarcoma patients

Second-line treatment of high-grade osteosarcoma (HGOS) patients is based on different approaches and chemotherapy protocols, which are not yet standardized. Although several drugs have been used in HGOS second-line protocols, none of them has provided fully satisfactory results and the role of rescue chemotherapy is not well defined yet. This article focuses on the drugs that have most frequently been used for second-line treatment of HGOS, highlighting the present knowledge on their mechanisms of action and resistance and on gene polymorphisms with possible impact on treatment sensitivity or toxicity. In the near future, validation of the so far identified candidate genetic biomarkers may constitute the basis for tailoring treatment by taking the patients' genetic background into account.

Genotypes of CYP2C8 and FGD4 and their association with peripheral neuropathy or early dose reduction in paclitaxel-treated breast cancer patients

Background:

The purpose of this study was to evaluate single-nucleotide polymorphisms (SNPs) in genes encoding key metabolising enzymes or involved in pharmacodynamics for possible associations with paclitaxel-induced peripheral neuropathy.

Methods:

The study population consists of 188 women from the multicenter, randomised, phase II ATX trial (BOOG2006-06; EudraCT number 2006-006058-83) that received paclitaxel and bevacizumab without or with capecitabine as first-line palliative therapy of HER2-negative metastatic breast cancer. Genotyping of CYP2C8*3 (c.416G>A), CYP3A4*22 (c.522-191C>T), TUBB2A (c.-101T>C), FGD4 (c.2044-236G>A) and EPHA5 (c.2895G>A) was performed by real-time PCR. Toxicity endpoints were cumulative dose (1) until first onset of grade ⩾1 peripheral neuropathy and (2) until first paclitaxel dose reduction from related toxicity (NCI-CTCAE version 3.0). SNPs were evaluated using the Kaplan–Meier method, the Gehan–Breslow–Wilcoxon test and the multivariate Cox regression analysis.

Results:

The rate of grade ⩾1 peripheral neuropathy was 67% (n=126). The rate of dose reduction was 46% (n=87). Age ⩾65 years was a risk factor for peripheral neuropathy (HR=1.87, P<0.008), but not for dose reduction. When adjusted for age, body surface area and total cumulative paclitaxel dose, CYP2C8*3 carriers had an increased risk of peripheral neuropathy (HR=1.59, P=0.045). FGD4 c.2044-236 A-allele carriers had an increased risk of paclitaxel dose reduction (HR per A-allele=1.38, P=0.036) when adjusted for total cumulative paclitaxel dose.

Conclusions:

These findings may point towards clinically useful indicators of early toxicity, but warrant further investigation.

Induction of C/EBP homologous protein-mediated apoptosis and autophagy by licochalcone A in non-small cell lung cancer cells

Licochalcone A (LCA), a flavonoid isolated from the famous Chinese medicinal herb Glycyrrhiza uralensis Fisch, presents obvious anti-cancer effects. In this study, the anti-cancer effects and potential mechanisms of LCA in non-small cell lung cancer (NSCLC) cells were studied. LCA decreased cell viability, increased lactate dehydrogenase release, and induced apoptosis in a concentration-dependent manner in NSCLC cells while not in human embryonic lung fibroblast cells. The expression of phosphatidylethanolamine-modified microtubule-associated protein light-chain 3 (LC3-II) and formation of GFP-LC3 punta, two autophagic markers, were increased after treatment with LCA. LCA-induced LC3-II expression was increased when combined with chloroquine (CQ), while knock-down of autophagy related protein (ATG) 7 or ATG5 reversed LCA-induced LC3-II expression and GFP-LC3 punta formation, suggesting that LCA induced autophagy in NSCLC cells. Inhibition of autophagy could not reverse the LCA-induced cell viability decrease and apoptosis. In addition, LCA increased the expression of endoplasmic reticulum stress related proteins, such as binding immunoglobulin protein and C/EBP homologous protein (CHOP). Knock-down of CHOP reversed LCA-induced cell viability decrease, apoptosis, and autophagy. Taken together, LCA-induced autophagic effect is an accompanied phenomenon in NSCLC cells, and CHOP is critical for LCA-induced cell viability decrease, apoptosis, and autophagy.

A phase I study afatinib/carboplatin/paclitaxel induction chemotherapy followed by standard chemoradiation in HPV-negative or high-risk HPV-positive locally advanced stage III/IVa/IVb head and neck squamous cell carcinoma

INTRODUCTION

Afatinib is an ErbB family receptor inhibitor with efficacy in head and neck squamous cell carcinoma (HNSCC). A phase I trial was conducted to determine the maximally tolerated dose (MTD) of afatinib in combination with carboplatin and paclitaxel as induction chemotherapy (IC).

MATERIAL AND METHODS

Patients with newly diagnosed, locally advanced HPV-negative or HPV-positive HNSCC with a significant smoking history were enrolled. Afatinib alone was given daily for two weeks as lead-in and subsequently given with carboplatin AUC 6mg/mlmin and paclitaxel 175mg/m(2) every 21days as IC. Afatinib was started at a dose of 20mg daily and dose escalated using a modified Fibonacci design. After completion of IC, afatinib was discontinued and patients received concurrent cisplatin 40mg/m(2) weekly and standard radiation. Toxicity was assessed using CTCAE version 4.0.

RESULTS

Seven of nine patients completed afatinib lead-in and IC. Five patients had partial response and two patients had stable disease after IC. Dose level 1 (afatinib 20mg) was well tolerated with one grade 3 (ALT elevation) and one grade 4 (neutropenia) toxicities. However, dose level 2 (afatinib 30mg) was not well tolerated with nine grade 3 (pneumonia, abdominal pain, diarrhea, pancytopenia, and UTI), two grade 4 (sepsis) and one grade 5 (death) toxicities.

CONCLUSIONS

The MTD of afatinib given with carboplatin AUC 6mg/mlmin and paclitaxel 175mg/m(2) is 20mg daily. Combination of afatinib at doses higher than 20mg with carboplatin and paclitaxel should be administered with caution due to the toxicities.