Identification of CHEK2 germline mutations in BRCA1/2 and PALB2 negative breast and ovarian cancer patients.

INTRODUCTION: The CHEK2 gene is known to be an important signal transducer involved in DNA repair, apoptosis, or cell cycle arrest in response to DNA damage. The mutations in this gene have been associated with a wide range of cancers, both sporadic and hereditary. Germline CHEK2 mutations are linked to an increased risk of breast cancer. Therefore, the aim of this study was to identify the prevalence of CHEK2 variants in BRCA1/2 and PALB2 negative early-onset patients with breast cancer and/or ovarian cancer in a Turkish population for the first time. METHODS: The study included 95 patients with BRCA1/2 and PALB2 negative early-onset breast cancer and/or ovarian cancer and also 60 unaffected women. All the intron/exon boundaries and coding exons of CHEK2 were subjected to mutational analysis by heteroduplex analysis and DNA sequencing. RESULTS: A total of 16 CHEK2 variants were found in breast cancer patients within the Turkish population. CHEK2 c.1100delC mutation studied in the CHEK2 gene most frequently was not detected in our study. The prevalence of variants of uncertain significance in CHEK2 was found to be 7.3% (n= 7) in BRCA1/2 and PALB2 mutation negative Turkish patients with early-onset breast and/or ovarian cancer. DISCUSSION/CONCLUSION: The present study may shed light on alternative variations that could be significant for understanding the prevalence and clinical suitability of the CHEK2 gene.

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.

Investigation of VHL gene associated with miR-223 in clear cell renal cell carcinoma.

BACKGROUND: Clear cell type renal cell carcinoma (ccRCC) is the most common renal cell carcinoma (RCC). In this study, we examined the expressions of VHL and miR-223 in ccRCC patients׳ tissues to investigate the possible role in the development of ccRCC. METHODS AND RESULTS: This study collected five expression profiles (GSE36139, GSE3, GSE73731, GSE40435, and GSE26032) from Gene Omnibus Data. Expressions of VHL and miR-223 in paraffinized tumor and normal tissues of 100 Turkish patients' ccRCC tissues were determined by bioinformatic data mining and real-time quantitative polymerase chain reaction (qRT-PCR). The VHL gene was subjected to mutational analysis by DNA sequencing, and pVHL was analyzed using western blotting. Our study's t-test and Pearson correlation analysis showed that VHL gene expression in tumoral tissues with a - 0.39-fold decrease was not significantly lower than normal tissues (p = 0.441), and a 0.97-fold increase miR-223 (p = 0.045) was determined by real-time PCR. Also, as a result of DNA sequence analysis performed in the VHL gene, it was found that 26% of the patients have mutations. The mutations for (VHL):c.60C>A (p.Val20=) and (VHL):c.467delA (p.Tyr156Leu) was detected for the first time in Turkish patients. CONCLUSIONS: The present study demonstrated that the differences in the expression levels of miR-223 have the potential to be biomarkers to determine the poor prognosis in ccRCC.

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.

Inhibitory Effects of Olea europaea Leaf Extract on Mesenchymal Transition Mechanism in Glioblastoma Cells.

BACKGROUND: Glioblastoma (GB) is the most aggressive form of brain tumor. Despite the current treatment methods, the survival rate of patients is very low. Therefore, there is a need to develop new therapeutic agents. The migration and invasion capacity of GB cells is related to mesenchymal transition (MT) mechanism. MATERIALS AND METHODS: The effect of OLE on MT was determined by analysis of the Twist, Snail, Zeb1, N-cadherin and E-cadherin genes in the EMT mechanism. The effect of OLE on cell migration was determined by wound healing test. RESULTS: 2 mg/ml OLE reduced Twist, Snail, Zeb1 and N-cadherin expression and the combination of OLE + TMZ (2 mg/ml OLE + 350 mM TMZ) increased E-cadherin and reduced Twist, Zeb1 and N-cadherin. In addition, co-treatment with OLE increased TMZ-induced anti-invasion properties thought suppressing transcription factors of MT mechanism. CONCLUSION: OLE can enhance the anti-MT activities of TMZ against GB and provide strong evidence that combined treatment with OLE and TMZ has the potential to be an effective alternative approach in GB therapy.

Evaluation of the Clinical Features Accompanied by the Gene Mutations: The 2 Novel PSEN1 Variants in a Turkish Early-onset Alzheimer Disease Cohort.

INTRODUCTION: Early-onset Alzheimer disease (EOAD) is an earlier Alzheimer disease form which is characterized by the mutations in the amyloid precursor protein, presenilin-1/2 (PSEN1/2), and triggering receptor expressed on myeloid cells 2 (TREM2). However, it is still necessary to report mutational screening in multiethnic groups to improve the genetic background of EOAD due to the variant classification challenge. METHODS: We performed targeted sequencing for the amyloid precursor protein, PSEN1, PSEN2, and TREM2 genes in 74 patients and 1 family diagnosed with EOAD. RESULTS: Among the detected variants, 8 were coding and 6 were noncoding in 15 of 74 patients. In PSEN1, 2 pathogenic coding variants (T274K and L364P) detected in 2 patients were novel and 3 coding variants (G183V, E318G, and L219P) detected in 2 patients were previously reported. We found 4 patients with the compound heterozygosity for the PSEN2 A23= and N43= and a family with the coexistence of them, and 1 patient with TREM2 Y38C. The coding variation frequency was 12.1%. In silico analysis indicated pathogenic potentials and clinical interpretations of the detected variants. CONCLUSION: Our study reveals the rare gene variants including novel ones from the Turkish EOAD cohort and provides to clinicians the list of detected variants in the screened genes, which may also be useful for accurate genetic counseling.

NEAT1 Is a Novel Oncogenic LncRNA and Correlated with miR-143 in Pediatric Oligodendrogliomas.

INTRODUCTION: The noncoding RNAs (ncRNAs) play a role in biological processes of various cancers including gliomas. The majority of these transcripts are uniquely expressed in differentiated tissues or specific glioma types. Pediatric oligodendroglioma (POG) is a rare subtype of diffuse glioma and accounts for <1% of pediatric brain tumors. Because histologically POG resembles adult OG, the same treatment is applied as adults. However, the significance in predicting outcomes in POG patients is unclear. In this study, we aimed to investigate the prognostic significance of expression -profiles of microRNA (miRNA) and long noncoding RNA -(LncRNA) in POGs. METHODS: We investigated the levels of 13 known miRNAs and 6 LncRNAs in tumor samples from 9 patients with primary POG by using RT-PCR and analyzed their association with outcomes. RESULTS: The expression levels of miR-21, miR-106a, miR-10b, and LncRNA NEAT1 were higher, and the expression level of miR-143 was lower in POG tissues compared with normal brain tissues (p = 0.006, p = 0.032, p = 0.034, p = 0.002, and p = 0.001, respectively). High levels of NEAT1 and low expression of miR-143 were associated with decreased probability of short disease-free survival (p = 0.018 and p = 0.022, respectively). DISCUSSION: NEAT1 and miR-143 levels could serve as reciprocal prognostic predictors of disease progression in patients with POG. New treatment models to regulate the expression levels of NEAT1 and miR-143 will bring a new approach to the therapy of POG.

Talazoparib nanoparticles for overcoming multidrug resistance in triple-negative breast cancer.

Herein, we investigated efflux pumps-mediated talazoparib-resistance in the treatment of triple-negative breast cancer (TNBC). Furthermore, we produced a novel talazoparib-solid lipid nanoparticles (SLNs) and then explored in vitro therapeutic efficacy of talazoparib-SLNs to overcome talazoparib-resistance in TNBC cells. Talazoparib-SLNs formulation was produced and then characterized. Calcein and Rho-123 were used to analyze the functional activity of drug efflux pumps in these cells. Additionally, RT-PCR, western blot and immunofluorescence analysis were used to detect the messenger RNA, and protein expression level, and cellular localization of the multidrug resistance (MDR1), breast cancer resistance protein (BCRP), and MRP1. We found that talazoparib efflux was mediated by BCRP and MRP1 pumps in TNBC cells. Talazoparib-SLNs could significantly enhance therapeutic efficacy of talazoparib. Furthermore, talazoparib-SLNs were more effective in the suppression of MDR1, BCRP, and MRP1 gene and protein expression levels than talazoparib. Consequently, this study suggests that talazoparib-SLNs formulation represents a promising therapeutic carrier to reverse MDR-mediated resistance in TNBC.

RNA-based markers in biopsy cores with atypical small acinar proliferation: Predictive effect of T2E fusion positivity and MMP-2 upregulation for a subsequent prostate cancer diagnosis.

BACKGROUND: Atypical small acinar proliferation (ASAP) is a precursor lesion of prostate cancer (PC), and PC develops from this suspicious focus or an unsampled malignant gland nearby. However, PC-related molecular alterations that could guide the timing of repeat biopsies and help monitor PC risk in ASAP-diagnosed patients have not been investigated. The purpose of this study was to first investigate the expression of seven different PC-related RNAs that included serine 2 (TMPRSS2): erythroblastosis virus E26 oncogene homolog (ERG) gene (TMPRSS2-ERG, T2E) fusion, alpha-methylacyl-CoA racemase (AMACR), kallikrein related peptidase 3 (KLK3), androgen receptor (AR), prostate cancer specific antigen 3 (PCA3), and matrix metalloproteinases (MMP)-2 and 9. METHODS: PC-related RNAs were evaluated using a real-time quantitative reverse transcription polymerase chain reaction (RT-qPCR) system in pathologically ASAP-diagnosed prostate biopsy cores from 55 patients presenting with a normal digital rectal examination and a PSA level of 4-10 ng/mL. RESULTS: We detected that positive T2E fusion status (P = 0.013) and the expression of AMACR (P = 0.016), AR (P = 0.016) and MMP-2 (P = 0.013) were independently and significantly associated with PC risk in ASAP patients. There were also several statistically significant correlations between expression levels. Additionally, we demonstrated that T2E fusion positive ASAP patients with higher MMP-2 expression were more likely to be diagnosed with PC at a subsequent biopsy during the follow-up period (P = 0.003). CONCLUSIONS: Although, more clinical validations are needed for the stratification of PC risk in ASAP-diagnosed biopsy cores, our current results indicate that the coexistence of T2E fusion positivity with MMP-2 upregulation may help clinicians adjust their biopsy timetable and/or assessment of PC risk in ASAP-diagnosed patients with a PSA level of 4-10 ng/mL.

BMN 673 (talazoparib): A potent PARP inhibitor for triple negative breast cancer with different genetic profile.

The objective of the present study was to elucidate the effect of BMN 673 (talozoparib) on BRCA1 mutant (HCC1937) and wild-type (MDA-MB-231) triple negative breast cancer (TNBC). The in vitro cytotoxicity results indicated that BMN 673 had considerable inhibitory effects on HCC1937 and MDA-MB-231 cell lines by inducing apoptosis, multicaspase activity, G2/M arrest, and altering the expression levels of apoptosis-related genes (P < 0.01). Additionally, BMN 673 indicated no toxicity on MCF-10A control cells until a certain concentration and incubation time. However, BMN 673, a novel and selective poly ADP ribose polymerase inhibitor, was more potent in TNBC cells bearing BRCA1 mutant than those with wild-type BRCA1. In conclusion, our study, for the first time, demonstrated a molecular mechanism of the induction of apoptosis by BMN 673 in TNBC with different genetic profile. However, further investigations regarding the exact molecular mechanisms underlying BMN 673-inducing apoptotic death and gene-cell line associations are required.