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Olea europaea leaf extract alters microRNA expression in human glioblastoma cells.

PurposeGlioblastoma multiforme (GBM) is the most common and the most lethal form of primary malignant tumors in the central nervous system. There is an increasing need for the development of more efficient therapeutic approaches for the treatment of these patients. One of the most attractive cancer therapy methods to date is the induction of tumor cell death by certain phytochemicals. Interestingly, bioactive compounds have been shown to alter micro RNA (miRNA) expression involved in several biological processes at the posttranscriptional level. The present study aimed to evaluate whether Olea europaea leaf extract (OLE) has an anticancer effect and modulates miRNA expression in GBM.Materials and methodsFirstly, the anti-proliferative activity of OLE and the nature of the interaction with temozolomide (TMZ) of OLE were tested in human glioblastoma cell line T98G cells by trypan blue and WST-1 assays and than realized miRNA PCR array analysis. Potential mRNA targets were analyzed bioinformatically.ResultsOLE exhibited anti-proliferative effects on T98G cell lines. Cells were treated with temozolomide (TMZ) in the presence OLE, and changes to miRNA expression levels were identified by PCR array analysis. miRNA target genes are involved in cell cycle and apoptotic pathways. Specifically, miR-181b, miR-153, miR-145, miR-137, and let-7d were significantly upregulated after treatment with both TMZ and OLE.ConclusionOur results suggest that OLE modulates the expression of some miRNAs related to anticancer activity in GBM and the response to TMZ. Further studies and validations are needed, but we suggest that OLE might be used for in vivo studies and future medical drug studies.

BRCA1/2 germline mutations and their clinical importance in Turkish breast cancer patients.

BRCA1/BRCA2 genes were screened in 117 patients with breast cancer by sequencing. Fourteen percent of patients tested positive for BRCA1/BRCA2 mutations. Four frame shift mutations, four pathogenic missense mutations, and 25 different sequence variations were detected. BRCA mutation positivity was significantly associated with Ki67 (p = .001). BRCA protein expressions were decreased in the patients harboring important mutations and polymorphisms (BRCA1;P508stop, V1740G, Q1182R, Q1756P and BRCA2;V2466A) related with disease. Our findings contribute significantly to the types of germline BRCA1/BRCA2 mutations and their biological effects in Turkish women. These data could help guide the management of BRCA1/BRCA2 mutation-carrying patients when considering breast-conserving therapy.

Molecular approach to genetic and epigenetic pathogenesis of early-onset colorectal cancer

Colorectal cancer (CRC) is the third most frequent cancer type and the incidence of this disease is increasing gradually per year in individuals younger than 50 years old. The current knowledge is that early-onset CRC (EOCRC) cases are heterogeneous population that includes both hereditary and sporadic forms of the CRC. Although EOCRC cases have some distinguishing clinical and pathological features than elder age CRC, the molecular mechanism underlying the EOCRC is poorly clarified. Given the significance of CRC in the world of medicine, the present review will focus on the recent knowledge in the molecular basis of genetic and epigenetic mechanism of the hereditary forms of EOCRC, which includes Lynch syndrome, Familial CRC type X, Familial adenomatous polyposis, MutYH-associated polyposis, Juvenile polyposis syndrome, Peutz-Jeghers Syndrome and sporadic forms of EOCRC. Recent findings about molecular genetics and epigenetic basis of EOCRC gave rise to new alternative therapy protocols. Although exact diagnosis of these cases still remains complicated, the present review paves way for better predictions and contributes to more accurate diagnostic and therapeutic strategies into clinical approach.

CK19, CK20, EGFR and HER2 status of circulating tumor cells in patients with breast cancer.

AIMS AND BACKGROUND The major cause of death in breast cancer patients is metastasis. Various biomarkers have been used for the early detection of circulating tumor cells in the peripheral blood of breast cancer patients. The aims of the current study were to analyze circulating tumor cells in the blood of breast cancer patients by investigating EGFR, CK19, CK20 and HER2 expression profiles and to evaluate their prognostic importance. METHODS CK19, CK20 and EGFR gene expression profiles were evaluated in the blood samples of 84 female patients with primary invasive ductal breast cancer and 20 healthy female volunteers using SYBR green-based real-time qPCR assays. HER2 expression analyses were conducted in 46 patients who had an HER2-positive primary tumor and in 30 healthy women to determine the cutoff level of positivity. RESULTS The positive rates of CK20, EGFR, CK19 and HER2 mRNA expression in the peripheral blood were 28.57% (24/84), 20.23% (17/84), 5.95% (5/84) and 2.17% (1/46), respectively. The high positive ratio of CK20 mRNA expression in the peripheral blood of breast cancer was identified for the first time in the current study. Significant differences were identified in CK20 expression status and several clinical parameters related with aggressiveness of tumors using a binary logistic regression analysis. Higher CK20-positive levels were observed in patients who had lymph node metastasis and advanced-grade primary tumors, which were estrogen receptor-negative. We have demonstrated that CK20 may be a novel biomarker that is useful to identify circulating tumor cells and predict breast cancer progression. CONCLUSIONS The results suggest that the investigation of CK20 mRNA with other biomarkers in the peripheral blood of breast cancer patients may be useful to monitor the presence of disseminated tumor cells in the blood circulation and to predict the prognosis of breast cancer.

Mutation analysis of the PARKIN, PINK1, DJ1, and SNCA genes in Turkish early-onset Parkinson’s patients and genotype-phenotype correlations

OBJECTIVE Variations in PARK genes (PRKN, PINK1, DJ-1, and SNCA) cause early-onset Parkinsons disease (EOPD) in different populations. In the current study, we aimed to evaluate the frequencies of variations in PARK genes and the effects of these variations on the phenotypes of Turkish EOPD patients. METHODS All coding regions and exon-intron boundaries of the PRKN, PINK1, DJ-1, and SNCA genes were screened by heteroduplex analysis followed by direct sequencing of the detected variants in 50 Turkish EOPD patients. These variants were evaluated using SIFT, PolyPhen, HSF, and LOVD web-based programs. RESULTS The frequency of EOPD-associated variations in the PRKN gene was 34%. Among these variations, p.A82E in exon 3 and p.Q409X in exon 11 was determined to be pathogenic. We also defined previously unknown cryptic variations, including c.872-35 G>A and c.872-28T>G in exon 8 of PRKN and c.252+30 T>G and c.322+4 A>G in exons 4 and 5 of DJ1, respectively, that were associated with EOPD. Although no significant association was observed between the PARK gene mutations and clinical features (P>0.05), the alterations were related to the clinical symptoms in each patient. CONCLUSION An increasing number of studies report that PRKN, PINK1, DJ1 and SNCA mutations are associated with early-onset Parkinsons disease; however, a limited number of studies have been conducted in Turkey. Additionally, our study is the first to evaluate the frequency of SNCA mutations in a Turkish population. The aim of this study was determine the frequency distributions of the PRKN, PINK1, DJ1, and SNCA gene mutations and to analyze the relationships between these genetic variations and the clinical phenotype of EOPD in Turkish patients.

Microsatellite instability status affects gene expression profiles in early onset colorectal cancer patients.

BACKGROUND The association between microsatellite instability (MSI) status and gene expression profiles in the early onset sporadic colorectal cancer (CRC) has not been clearly established. The aim of this study was to identify the altered gene expression patterns depending on the MSI status of early onset CRC and determine specific biomarkers that could provide novel therapeutic molecular targets in the Turkish population. MATERIALS AND METHODS MSI markers (BAT25, BAT26, D2S123, D5S346, and D17S250) were investigated in tumors from 36 early onset sporadic CRC patients in whom gene expression profiles were analyzed previously. The relationship between the gene expression profiles depending on MSI status was evaluated. RESULTS A total of 15 tumors (16.66%) were identified as having MSI and 21 tumors (58.33%) were identified as having microsatellite stability (MSS). CK20 and MAP3K8 upregulation, observed in MSS tumors, was significantly associated with lymph node metastasis, recurrence, and/or distant metastasis and a short median survival (P < 0.05). REG1A upregulation is also correlated with recurrence and/or distant metastasis and a short median survival in patients with MSI tumors (P < 0.05). CONCLUSIONS High expression levels of CK20 and MAP3K8 in MSS tumors and REG1A in MSI tumors correlated with a poor prognosis in CRC patients. Further studies and validations are required; these genes may provide novel therapeutic molecular targets for the development of anticancer drugs related to MSI status for early onset CRC treatment.

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 (β2=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.

Expression and clinical significance of miRNAs that may be associated with the FHIT gene in breast cancer

The dysregulation of miRNA expression has frequently been observed in breast cancer. Therefore, we investigated the expression profile of miRNAs that may be associated with expression of the FHIT gene in breast cancer and assessed their clinicopathological significance. The expression levels of miR-143, miR-663a, miR-668, miR-922 and FHIT were analyzed in normal and malignant breast tissues from 65 patients with breast cancer. We studied the correlation between the expression of miR-143, miR-663a, miR-668, miR-922 and FHIT and the clinicopathological features presented by the patients. The expression levels of the miRNAs and FHIT were downregulated in breast cancer tissue. The expression levels of miR-143, miR-663a and miR-668 were significantly reduced in FHIT downregulated tumors. miR-668 expression was also significantly altered relative to FHIT down- and up- regulated tumor tissues. Reduced miR-663a expression was statistically associated with high-grade ER/PR (+) status, benign reactive hyperplasia, lymph-node metastasis, in-situ component >25% and Ki 67>15% compared with non-tumor tissues. Additionally, reduced miR-668 expression was significantly different between tumors with and without lymph-node metastasis. miR-668 may play an important role in breast cancer development and progression by regulating the expression of FHIT. Furthermore, miR-668 and miR-663a may be potential prognostic biomarkers for breast cancer.