Search results for "Cell Line"
showing 10 items of 2924 documents
A study of PD-L1 expression in KRAS mutant non-small cell lung cancer cell lines exposed to relevant targeted treatments.
2017
We investigated PD-L1 changes in response to MEK and AKT inhibitors in KRAS mutant lung adenocarcinoma (adeno-NSCLC). PD-L1 expression was quantified using immunofluorescence and co-culture with a jurkat cell-line transfected with NFAT-luciferase was used to study if changes in PD-L1 expression in cancer cell lines were functionally relevant. Five KRAS mutant cell lines with high PD-L1 expression (H441, H2291, H23, H2030 and A549) were exposed to GI50 inhibitor concentrations of a MEK inhibitor (trametinib) and an AKT inhibitor (AZD5363) for 3 weeks. Only 3/5 (H23, H2030 and A549) and 2/5 cell lines (H441 and H23) showed functionally significant increases in PD-L1 expression when exposed to…
Recent Insights into the Development of Preclinical Trastuzumab- Resistant HER2+ Breast Cancer Models.
2018
Background: Overexpression and amplification of the human epidermal growth factor receptor 2 (HER2) occur in 20% of total breast carcinomas. HER2-overexpression is implicated in disease initiation and progression and associated with poor prognosis. Trastuzumab, a humanized monoclonal antibody, is the standard HER2-targeted therapy for early and metastatic HER2-amplified breast cancer patients. Trastuzumab has significantly increased clinical benefit in HER2+ metastatic and adjuvant settings; however, it is not effective for many patients due to primary or acquired resistance to the drug. During the last decade, many studies have revealed a number of novel molecular traits of HER2+ breast c…
miR‐200c and phospho‐AKT as prognostic factors and mediators of osteosarcoma progression and lung metastasis
2016
Lung metastasis is the major cause of death in osteosarcoma patients. However, molecular mechanisms underlying this metastasis remain poorly understood. To identify key molecules related with pulmonary metastasis of pediatric osteosarcomas, we analyzed high-throughput miRNA expression in a cohort of 11 primary tumors and 15 lung metastases. Results were further validated with an independent cohort of 10 primary tumors and 6 metastases. In parallel, we performed immunohistochemical analysis of activated signaling pathways in 36 primary osteosarcomas. Only phospho-AKT associated with lower overall survival in primary tumors, supporting its role in osteosarcoma progression. CTNNB1 expression a…
The role of miR-26a and miR-30b in HER2+ breast cancer trastuzumab resistance and regulation of the CCNE2 gene
2016
AbstractA subset of HER2+ breast cancer patients manifest clinical resistance to trastuzumab. Recently, miR-26a and miR-30b have been identified as trastuzumab response regulators, and their target gene CCNE2 seems to play an important role in resistance to trastuzumab therapy. Cell viability was evaluated in trastuzumab treated HER2+ BT474 wt (sensitive), BT474r (acquired resistance), HCC1954 (innate resistance), and MDA-MB-231 (HER2−) cell lines, and the expression of miR-26a, miR-30b, and their target genes was measured. BT474 wt cell viability decreased by 60% and miR-26a and miR-30b were significantly overexpressed (~3-fold, p = 0.003 and p = 0.002, respectively) after trastuzumab trea…
Suppressive role exerted by microRNA-29b-1-5p in triple negative breast cancer through SPIN1 regulation
2017
MiR-29 family dysregulation occurs in various cancers including breast cancers. We investigated miR-29b-1 functional role in human triple negative breast cancer (TNBC) the most aggressive breast cancer subtype. We found that miR-29b-1-5p was downregulated in human TNBC tissues and cell lines. To assess whether miR- 29b-1-5p correlated with TNBC regenerative potential, we evaluated cancer stem cell enrichment in our TNBC cell lines, and found that only MDA-MB-231 and BT-20 produced primary, secondary and tertiary mammospheres, which were progressively enriched in OCT4, NANOG and SOX2 stemness genes. MiR-29b-1-5p expression inversely correlated with mammosphere stemness potential, and miR-29b…
A two-gene epigenetic signature for the prediction of response to neoadjuvant chemotherapy in triple-negative breast cancer patients
2019
Background Pathological complete response (pCR) after neoadjuvant chemotherapy (NAC) in triple-negative breast cancer (TNBC) varies between 30 and 40% approximately. To provide further insight into the prediction of pCR, we evaluated the role of an epigenetic methylation-based signature. Methods Epigenetic assessment of DNA extracted from biopsy archived samples previous to NAC from TNBC patients was performed. Patients included were categorized according to previous response to NAC in responder (pCR or residual cancer burden, RCB = 0) or non-responder (non-pCR or RCB > 0) patients. A methyloma study was performed in a discovery cohort by the Infinium HumanMethylation450 BeadChip (450K arra…
Anticancer properties of 4-thiazolidinone derivatives depend on peroxisome proliferator-activated receptor gamma (PPARγ)
2017
Peroxisome proliferator-activated receptors (PPARs) play an important role in numerous chronic diseases such as diabetes, obesity, atherosclerosis and cancer, and PPAR modulators are among the approved drugs and drug-candidates for their treatment. The aim of this study was to elucidate the involvement of PPARs in the mechanism of cytotoxic and pro-apoptotic action of novel anticancer 4-thiazolidinone derivatives (Les-2194, Les-3377, Les-3640) and approved 4-thiazolidinones (Rosiglitazone, Pioglitazone) towards the human squamous carcinoma (SCC-15) cell line. Experiments with 4-thiazaolidinone derivatives and PPAR-specific siRNA were conducted and PPARα, PPARβ and PPARγ mRNA expression was …
Mid-region parathyroid hormone-related protein is a genome-wide chromatin-binding factor that promotes growth and differentiation of HB2 epithelial c…
2018
Human parathyroid hormone-related protein (PTHrP) is a polyhormone that undergoes proteolytic cleavage producing smaller peptides which exert diversified biological effects. PTHrP signalization is prominently involved in breast development and physiology, but the studies have been focused onto either N-terminal species or full-length protein introduced by gene transfer techniques. Our present work investigates for the first time the effect of the mid-region PTHrP secretory form, that is, the fragment [38-94], on HB2 non-tumoral breast epithelial cells. We examined viability/proliferation of cells grown in PTHrP-containing media supplemented with different serum concentration and on differen…
Vitamin D and Its Analogues Decrease Amyloid-β (Aβ) Formation and Increase Aβ-Degradation
2017
Alzheimer’s disease (AD) is characterized by extracellular plaques in the brain, mainly consisting of amyloid-β (Aβ), as derived from sequential cleavage of the amyloid precursor protein. Epidemiological studies suggest a tight link between hypovitaminosis of the secosteroid vitamin D and AD. Besides decreased vitamin D level in AD patients, an effect of vitamin D on Aβ-homeostasis is discussed. However, the exact underlying mechanisms remain to be elucidated and nothing is known about the potential effect of vitamin D analogues. Here we systematically investigate the effect of vitamin D and therapeutically used analogues (maxacalcitol, calcipotriol, alfacalcidol, paricalcitol, doxercalcife…
Identification of potential therapeutic compounds for Parkinson's disease using Drosophila and human cell models.
2017
Abstract Parkinson's disease (PD) is the second most common neurodegenerative disorder after Alzheimer's disease. It is caused by a loss of dopaminergic neurons in the substantia nigra pars compacta, leading to a decrease in dopamine levels in the striatum and thus producing movement impairment. Major physiological causes of neurodegeneration in PD are oxidative stress (OS) and mitochondrial dysfunction; these pathophysiological changes can be caused by both genetic and environmental factors. Although most PD cases are sporadic, it has been shown that 5–10% of them are familial forms caused by mutations in certain genes. One of these genes is the DJ-1 oncogene, which is involved in an early…