Association between the apoptotic effect of Cabazitaxel and its pro-oxidant efficacy on the redox adaptation mechanisms in prostate cancer cells with different resistance phenotypes.

Redox adaptation causes poor prognosis by adapting cancer cells to excessive oxidative stress. Previously, we introduced an oxidative stress-resistant metastatic prostate cancer (mPC) model (LNCaP-HPR) that redox adaptation reduced the effect of Cabazitaxel (Cab), the last taxane-derivative for metastatic castration-resistant PC (mCRPC). Whereas, we investigated for the first time whether there is an association between the altered apoptotic effect and pro-oxidant efficacy of Cab on the redox adaptation in PC cells with different phenotypes, including LNCaP mPC, LNCaP-HPR, C4-2 mCRPC, and RWPE-1 cells. Cab was shown pro-oxidant efficacy proportionally with the apoptotic effect, more prominent in the less aggressive LNCaP cells, by increasing the endogenous ROS, mitochondrial damage, and inhibiting nuclear ROS scavengers, p-Nrf2 and HIF-1α. However, the pro-oxidant and apoptotic effect was lower in the LNCaP-HPR and C4-2 cells, indicating that the drug sensitivity of the cells adapted to survive with more ROS was reduced via altered regulation of redox adaptation. Additionally, unlike LNCaP, Cab caused an increase in the p-NF-κB activation, suggesting that the p-NF-κB might accompany maintaining survival with the increased ROS in the aggressive PC cells. Moreover, the cytotoxic and apoptotic effects of Cab were less on RWPE-1 cells compared to LNCaP but were closer to those on the more aggressive LNCaP-HPR and C4-2 cells, except for the changing pro-oxidant effect of Cab. Consequently, this study indicates the variable pro-oxidant effects of Cab on redox-sensitive proteins, which could be a target for improving Cab's apoptotic effect more in aggressive PC cells.

The regulatory effect of cabazitaxel on epithelial-mesenchymal transition in metastatic prostate cancer.

Introduction: : Epithelial-mesenchymal transition (EMT) is a critical mechanism that promotes cancer cells to metastasis. Therefore, EMT regulation has become an important target in anticancer therapy approaches in recent years. However, in metastatic prostate cancer (PC), the EMT regulatory effect has not fully understood for cabazitaxel (Cbx), a third line taxane-based chemotherapeutic for metastatic castration-resistant PC. Aim: In this study, we investigated the antimetastatic and EMT-regulatory effects of Cbx on hormone-sensitive metastatic PC cells. Materials and Methods: The anticancer effects of Cbx were assessed by WST-1 and Annexin V analysis. The antimetastatic effect of Cbx was evaluated by wound healing and quantitative reverse transcription polymerase chain reaction through EMT-mesenchymal-to-epithelial transition (MET) markers as well as EMT-repressor microRNAs (miRNAs) in Cbx-treated LNCaP cells. Results: Our results showed that, in addition to its apoptotic and anti-migratory activities, Cbx exhibited the EMT-repressor effects through the prominent downregulation of matrix metalloproteinase-9 and Snail levels as EMT-promoting factors, and the significant upregulation of the certain miRNAs, including miR-205, miR-524, and miR-124, which play a role in EMT-repressing by targeting regulators of the EMT-associated genes. Conclusion: Although further evaluations are needed to improve the findings, we showed that, in addition to its classical taxane function, Cbx has a regulatory effect on EMT-MET cycling in hormone-sensitive metastatic PC.

An in vitro redox adaptation model for metastatic prostate cancer: Establishing, characterizing and Cabazitaxel response evaluating.

Little is known about the redox-adapted cancer cells for understanding their pharmacologically targetable features and chemotherapeutic responses. Thus, we present the first in vitro redox adaptation model for metastatic prostate cancer (mPC), LNCaP-hydrogen peroxide resistant (LNCaP-HPR), with enhanced oxidative stress resistance accompanying poor Cabazitaxel response. After establishing, the cells were characterized by comparing the viability, death, oxidative stress, total glutathione (GSH) levels and the mRNA and protein levels of the redox-sensitive transcription factors responsible for the adaptation, Nrf-2, NF-κB and HIF-1α. Then, the apoptotic effect of Cabazitaxel was evaluated in LNCaP mPC, LNCaP-HPR and C4-2 metastatic castration-resistant (mCRPC) cells. In response to H2 O2 , viability, oxidative stress and the total GSH levels of LNCaP-HPR cells have confirmed the oxidative stress resistance. Nrf-2, NF-κB and HIF-1α were upregulated in LNCaP-HPR cells, not in LNCaP, confirming that resistant cells were much less affected by exogenous oxidative stress. Unlike LNCaP, LNCaP-HPR cells were less sensitive to Cabazitaxel, as closer to the response of C4-2 mCRPC cells, indicating that redox adaptation decreased Cabazitaxel response. This is the first evaluated association between redox adaptation and poor Cabazitaxel response, suggesting that in vitro Cabazitaxel efficiency is affected by PC cells' endogenous oxidative stress tolerance.

The Anticancer Effect of Inula viscosa Methanol Extract by miRNAs' Re-regulation: An in vitro Study on Human Malignant Melanoma Cells.

Alternative and natural therapies are needed for malignant melanoma (MM), the most deadly skin cancer type due to chemotherapy's limited effect. In the present study, we evaluated the anticancer potentials of Inula viscosa methanol and water extracts (IVM and IVW) on MM cells, A2058 and MeWo, and normal fibroblasts. After the chromatographic and antioxidant activity analysis, their antiproliferative effects were determined with the increasing doses for 24-72 h. IVM induced more cell death in a dose and time-dependent manner in MM cells compared to IVW. This effect was probably due to the higher amount of phenolics in it. IVM significantly induced more apoptotic death in MM cells than fibroblasts (p < 0.01), which was also supported morphologically. IVM also caused cell cycle arrest at G0/G1 and G2/M phases in A2058 and MeWo, respectively, and suppressed the migration ability of MM cells (p < 0.01). Additionally, IVM was found to have significant potential in regulating MM-related miRNAs, upregulating miR-579 and miR-524, and downregulating miR-191 and miR-193, in MM cells (p < 0.05, p < 0.01). As a result, the anticancer effect of IVM via regulating miRNAs' expression has been demonstrated for the first time. Thus, IVM, with these potentials, may be a promising candidate for MM treatment.

Association between the anticancer efficacy of cabazitaxel and toll-like receptor 4 mediating signaling pathways in metastatic castration-resistant prostate cancer cells.

BACKGROUND: We evaluated the effect of cabazitaxel (CAB) as a third-line taxane on Toll-like receptor 4 (TLR4)-mediated signaling pathways, especially NF-κB activity, in metastatic castration-resistant prostate cancer (mCRPC) cells. METHODS: CAB cytotoxicity was determined by WST-1 assay. To assess the relationship between CAB efficacy and TLR4 signaling pathways, RT-PCR, western blot and immunofluorescence analysis were performed. Additionally, CAB-mediated apoptotic cell death was assessed by Annexin V and RT-PCR analysis. RESULTS: Our results demonstrated that CAB exerted considerably cytotoxic and apoptotic effects on PC-3 mCRPC cells (p < 0.05). CAB treatment altered TLR4 expression level in a dose-dependent manner. Furthermore, 1 nM CAB treatment significantly induced NF-κB activity through p65 nuclear localization and increased the expression level of caspase-3, Bax and p53. Interestingly, total apoptotic cell death and IRF3 protein levels were increased at 5 nM concentration of CAB despite a decrease in the levels of both NF-κB and pro-apoptotic genes. CONCLUSIONS: Therefore, NF-κB activity may be a potential target for the efficacy of CAB in mCRPC cells.

Contribution of functional dopamine D2 and D3 receptor variants to motor and non-motor symptoms of early onset Parkinson's disease.

In the present study, we focused on investigating the contribution of functional dopamine D2 and D3 receptor variants to motor and/or non-motor symptoms of early onset Parkinson's disease (EOPD). Three functional single nucleotide polymorphisms (SNPs), DRD3 rs6280, DRD2 rs2283265 and DRD2 rs1076560, were genotyped in 128 Turkish EOPD patients and then, statistical analysis was conducted for the potential impacts of SNPs on clinical parameters. All three SNPs were found to be statistically significant in terms of PD-related pain: DRD3 [rs6280; risk allele "T" for pain; p = 0.031; odds ratio (OR)=4.25], DRD2 [rs2283265; risk allele "A" for pain; p = 0.001; OR=8.47] and, DRD2 [rs1076560; risk allele "A" for pain; p = 0.022; OR=4.58]. Additionally, bilateral disease [p = 0.011; OR=5.10] and gender [risk group "female"; p = 0.003; OR=8.53] were also identified as significant univariate risk factors for PD-related pain. Based on logistic regression analysis conducted with the significant univariate risk factors, this the first report to clarify that a female patient with bilateral PD and DRD2 rs2283265 polymorphism has a significant risk for PD-related pain. Our findings might contribute to improve life quality by offering treatment options for pain in PD patients with these clinical and genetic features.

Clinicopathologic features and genetic characteristics of the BRCA1/2 mutation in Turkish breast cancer patients.

The aim of this study was to identify the frequency and spectrum of germline BRCA1/2 pathogenic alterations in a cohort of patients with breast carcinoma. In this study, a total of 603 breast cancer subjects from Turkey were screened for BRCA1/BRCA2 mutations using HDA and Sanger sequencing. In the present study, 21 BRCA1 and BRCA2 pathogenic variants were detected in 30 patients and BRCA1/2 mutations were significantly associated with a family history of breast/ovarian cancer. Analysis of overall survival for BRCA1/BRCA2 mutation carriers showed a trend for poor overall survival only in BRCA1 carriers, although this was not statistically significant in BRCA1 and BRCA2 mutation carriers. The c.5266dupC mutation is one of the most frequently reported mutations in BRCA1 and was identified in five breast cancer patients in our study. The most common BRCA2 gene mutations in the present study were c.8940delA and c.9097dupA, which were found in seven patients. We found mostly BRCA1 and BRCA2 mutation carriers in those patients who showed hormone-positive features. In conclusion, our data showed differences in the distribution of the mutation spectrum of BRCA1 and BRCA2 in Turkey.

Synergistic effects of hormone therapy drugs and usnic acid on hormone receptor-positive breast and prostate cancer cells.

The aim of this study was to investigate the combined effects of usnic acid (UA) and Tamoxifen (Tam) or Enzalutamide (Enz) on hormone receptor-positive breast and prostate cancer (BC and PC), respectively. The antiproliferative and apoptotic effects of Tam or Enz alone and in combination with UA on MCF7 and LNCaP cancer cells were detected. The results of the WST-1 assay indicated that UA was a promising anticancer compound that significantly enhanced the effectiveness of hormone therapy drugs compared with each drug alone (combination index < 1). In addition, the combination of UA with Tam or Enz remarkably induced more cell cycle arrest at the G0/G1 phase and apoptosis than only drug-treated cells (P < 0.01). Consequently, our findings suggest that the combination of UA with Tam or Enz may be a potential therapeutic approach for the treatment of BC and PC and further studies are required to exploit the potential mechanisms of synergistic effects.

Investigation of new treatment option for hepatocellular carcinoma: a combination of sorafenib with usnic acid.

OBJECTIVES: Sorafenib (SOR) is an orally administered molecular targeted agent in the systemic chemotherapy of hepatocellular carcinoma (HCC). However, the partial response of SOR is limited due to its adverse side effect and high heterogeneity and resistant phenotype of HCC. In the current study, we investigated synergistic effects of SOR and usnic acid (UA) on HCC cell lines including HepG2 and SNU-449, and a normal cell line, HUVEC. METHODS: The antiproliferative and apoptotic effects of combination therapy and SOR alone were analysed by WST-1 and Annexin V analysis, respectively. Furthermore, cell cycle, gene expression analysis of SOR-targeted kinases and acridine orange-ethidium bromide staining were also performed in combined treatments. KEY FINDINGS: Our results demonstrated that SOR and UA combination indicated a strong synergism in HCC cell lines and reduced SOR toxicity in HUVEC cells. Additionally, the combination treatment SOR and UA significantly induced much more apoptotic cell death and G0/G1 arrest through downregulation of SOR-targeted kinases. CONCLUSIONS: Consequently, SOR and UA combination could be a new therapeutic strategy for HCC treatment.

In vitro cytotoxic and antiproliferative effects of usnic acid on hormone-dependent breast and prostate cancer cells.

The aim of the current study was first to investigate cytotoxic activity of usnic acid (UA) on hormone-dependent breast and prostate cancer, and normal cells. Cells were treated with increasing concentrations (25 to 150 µM) of UA for 48 hours and cell viability, quantitative and morphological analysis of cell death, and cell cycle analysis were performed. UA was shown to have selective cytotoxicity on hormone-dependent cancer cells with the IC50 levels of 71.4 and 77.5 µM for MCF7 and LNCaP cells, respectively. UA induced apoptotic cell death and G0/G1 cell cycle arrest without damaging normal cells. MCF7 cells were more sensitive to UA than LNCaP cells. Our results first revealed that UA is a promising candidate as an alternative agent for hormone-dependent breast and prostate cancers. However, molecular mechanism underlying the UA-mediated cell death in cancer cells should be investigated further.

T2E (TMPRSS2-ERG) fusion transcripts are associated with higher levels of AMACR mRNA and a subsequent prostate cancer diagnosis in patients with atypical small acinar proliferation.

Genetic rearrangements involving androgen-regulated transmembrane protease serine 2 (TMPRSS2) and genes from the ETS transcription factor family, most commonly ERG and ETV1, result in alteration that responsible for oncogenic activity in prostate cancer (PC). The aims of the present study were to: 1) investigate the frequency of these fusion transcripts in prostate tissue samples obtained from patients diagnosed with atypical small acinar proliferation (ASAP), 2) determine any clinical significance of T2E expression at the RNA level in predicting PC detection in subsequent biopsies, and 3) evaluate expression of the PC marker, alpha-methylacyl-CoA racemase (AMACR), according to T2E status by real-time quantitative reverse transcription PCR (RT-qPCR). T2E transcripts were detected in 31.7% (n=20) of the patients examined, and this was significantly associated with subsequent detection of PC in ASAP patients with a prostate specific antigen (PSA) level of 4-10ng/ml (p=0.045). AMACR expression was also significantly higher in the patients who were diagnosed with PC in subsequent biopsies than in the patients who were not diagnosed with PC (p=0.034) and in T2E-positive ASAP patients (p=0.002) compared to T2E-negative ASAP patients. Although these results need to be further clinically validated, we suggest that the presence of T2E transcript, in association with higher AMACR expression, is an indicator of PC risk from a T2E-positive focus or an unsampled malignant gland adjacent to a T2E-positive site in ASAP lesions.

Epigenetic approach to early-onset Parkinson's disease: low methylation status of SNCA and PARK2 promoter regions.

Background and aim The effect of epigenetic modifications in the genes related to Parkinson's disease (PD) is still unclear. In the present study, we investigated methylation status of SNCA and PARK2 genes in patients with early-onset Parkinson's disease (EOPD). Materials and methods The promoter region methylation status of SNCA and PARK2 genes was evaluated by methylation specific-PCR (MSP) in 91 patients with EOPD and 52 healthy individuals. Results The methylation of SNCA and PARK2 promoter regions were significantly lower in EOPD patients compared to the control group (P = 0.013 and P = 0.03, respectively). We also found that the methylation status of the SNCA might be associated with positive family history of PD (P = 0.042). Conclusion Although it should be supported by further analysis, based on the results of the present study, the methylation status of SNCA and PARK2 genes might contribute to EOPD pathogenesis.

Association of MDR1, CYP2D6, and CYP2C19 gene polymorphisms with prophylactic migraine treatment response.

Prophylactic therapy response varies in migraine patients. The present study investigated the relationship between the resistance to the drugs commonly used in prophylactic therapy and the possible polymorphic variants of proteins involved in the metabolism of these drugs. Migraine patients with the MDR1 3435TT genotype exhibited a better treatment response to topiramate than migraine patients with the CC and CT genotypes (p=0.020). The MDR1 C3435T polymorphism was also found to be a higher risk factor for topiramate treatment failure in a comparison of the number of days with migraine (ß2=1.152, p=0.015). However, there was no significant relationship between the treatment response to topiramate and either the CYP2D6 or CYP2C19 polymorphism, and there were no significant correlations between the treatment responses to amitriptyline, propranolol, and valproic acid and the MDR1, CYP2D6 and CYP2C19 gene polymorphisms. This is the first study to investigate the effect of the polymorphic variants on prophylactic therapy response in migraine patients.

The effect of aluminium-stress and exogenous spermidine on chlorophyll degradation, glutathione reductase activity and the photosystem II D1 protein gene (psbA) transcript level in lichen Xanthoria parietina.

In this study, the effects of short-term aluminium toxicity and the application of spermidine on the lichen Xanthoria parietina were investigated at the physiological and transcriptional levels. Our results suggest that aluminium stress leads to physiological processes in a dose-dependent manner through differences in lipid peroxidation rate, chlorophyll content and glutathione reductase (EC 1.6.4.2) activity in aluminium and spermidine treated samples. The expression of the photosystem II D1 protein (psbA) gene was quantified using semi-quantitative RT-PCR. Increased glutathione reductase activity and psbA mRNA transcript levels were observed in the X. parietina thalli that were treated with spermidine before aluminium-stress. The results showed that the application of spermidine could mitigate aluminium-induced lipid peroxidation and chlorophyll degradation on lichen X. parietina thalli through an increase in psbA transcript levels and activity of glutathione reductase (GR) enzymes.