Methyl CpG binding protein MBD2 has a regulatory role on the BRCA1 gene expression and its modulation by resveratrol in ER+, PR+ & triple-negative breast cancer cells.

BACKGROUND: Resveratrol has demonstrated its ability to regulate BRCA1 gene expression in breast cancer cells, and previous studies have established the binding of MBD proteins to BRCA1 gene promoter regions. However, the molecular mechanism underlying these interactions remains to be elucidated. The aimed to evaluate the impact of MBD proteins on the regulation of BRCA1, BRCA2, and p16 genes and their consequential effects on breast cancer cells. METHODS: Efficacy of resveratrol was assessed using the MTT assay. Binding interactions were investigated through EMSA, ChIP, & MeIP assay. Expression analyses of MBD genes and proteins were conducted using qRT-PCR and western blotting, respectively. Functional assays, including clonogenic, migratory, and sphere formation assays were used to assess cancer cells' colony-forming, metastatic, and tumor-forming abilities. The cytotoxicity of resveratrol on cancer cells was also tested using an apoptosis assay. RESULTS: The study determined an IC50 of 30µM for resveratrol. MBD proteins were found to bind to the BRCA1 gene promoter. Resveratrol exhibited regulatory effects on MBD gene expression, subsequently impacting BRCA1 gene expression and protein levels. Higher concentrations of resveratrol resulted in reduced colony and sphere formation, decreases migration of cancer cells, and an increases number of apoptotic cells in breast cancer cells. Impact Identification of MBD2-BRCA1 axis indicates their significant role in the induction of apoptosis and reduction of metastasis and proliferation in breast cancer cells. Further therapy can be designed to target these MBD proteins and resveratrol could be used along with other anticancer drugs to target breast cancer. CONCLUSIONS: In conclusion MBD2 protein interact to the BRCA1 gene promoter, and resveratrol modulates MBD2 gene expression, which in turn regulates BRCA1 gene expression, and inhibits cell proliferation, migration, and induces apoptosis in ER+, PR+ & Triple negative breast cancer cells.

Efficient and stereoselective synthesis of sugar fused pyrano[3,2-c]pyranones as anticancer agents.

A highly stereoselective, efficient and facile route was achieved for the synthesis of novel and biochemically potent sugar fused pyrano[3,2-c]pyranone derivatives starting from inexpensive, naturally occurring d-galactose and d-glucose. First, ß-C-glycopyranosyl aldehydes were synthesized from these d-hexose sugars in six steps, with overall yields 41-55%. Next, two different 1-C-formyl glycals were synthesized from these ß-C-glycopyranosyl aldehydes by treatment in basic conditions. The optimization of reaction conditions was carried out following reactions between 1-C-formyl galactal and 4-hydroxycoumarin. Next, 1-C-formyl galactal and 1-C-formyl glucal were treated with nine substituted 4-hydroxy coumarins at room temperature (25 °C) in ethyl acetate for ∼1-2 h in the presence of l-proline to obtain exclusively single diastereomers of pyrano[3,2-c]pyranone derivatives in excellent yields. Four compounds were found to be active for the MCF-7 cancer cell line. The MTT assay, apoptosis assay and migration analysis showed significant death of the cancer cells induced by the synthesized compounds.

Role of identified proteins in the proteome profiles of CDK4/6 inhibitor-resistant breast cancer cell lines.

Abemaciclib (Ab) and palbociclib (Pb) are CDK4/6 inhibitors used to cure advanced breast cancer (BC). However, acquired resistance is a major challenge. The molecular mechanisms and signature proteins of therapy resistance for Ab and Pb drugs need to be explored. Here we developed resistant cells for Ab and Pb drugs in MCF-7 cell lines and explored the mechanisms and signature proteins of therapy resistance in BC. Proteome profiling was performed using the label-free proteome-orbitrap-fusion-MS-MS technique. Gene ontology (GO)-terms, KEGG pathways and network analysis were performed for the proteome data. Drug-resistant cells showed increased drug tolerance, enhanced colony formation potential and an increased gap-healing tendency for the respective drug. Up-regulation of survival genes (BCL-2 and MCL-1) and down-regulation of apoptosis inducers were observed. Drug-resistance markers (MDR-1 and ABCG2 (BCRP)) along with ESR-1, CDK4, CDK6, and cyclin-D1 genes were up-regulated in resistant cells. A total of 237 and 239 proteins were found to be differentially expressed in the Ab and Pb-resistant cells, respectively. Down-regulated proteins induce apoptosis signalling and nucleotide metabolisms and restrict EGFR signalling; however, up-regulated proteins induce Erk, wnt-ß-catenin, VEGFR-PI3K-AKT, glucose transportation, and hypoxia signalling pathways and regulate hydrogen peroxide signalling pathways. The panel of identified proteins associated with these pathways might have characteristics of molecular signature and new drug targets for overcoming drug resistance in breast cancer.

In silico prediction and interaction of resveratrol on methyl-CpG binding proteins by molecular docking and MD simulations study.

Resveratrol enhances the BRCA1 gene expression and the MBD family of proteins bind to the promoter region of the BRCA1 gene. However, the molecular interaction is not yet reported. Here we have analyzed the binding affinity of resveratrol with MBD proteins. Our results suggest that resveratrol binds to the MBD proteins with higher binding affinity toward MeCP2 protein (ΔG = -6.5) by sharing four hydrogen bonds as predicted by molecular docking studies. Further, the molecular dynamics simulations outcomes showed that the backbones of all three protein-ligand complexes are stabilized after the period of 75 ns, constantly fluctuating around the deviations of 0.4 Å, 0.5 Å and 0.7 Å for MBD1, MBD2 and MeCP2, respectively. The inter-molecular hydrogen bonding trajectory analysis for protein-ligand complexes also support the strong binding between MeCP2-resveratrol complex. Further, binding free energy calculations showed binding energy of -94.764 kJ mol-1, -53.826 kJ mol-1 and -36.735 kJ mol-1 for MeCP2-resveratrol, MBD2-resveratrol and MBD1-resveratrol complexes, respectively, which also supported our docking results. Our study also highlighted that the MBD family of proteins forms a binding interaction with other signaling proteins that are involved in various cancer initiation pathways.

Schleichera oleosa Seed Extract Reduced the Proliferation of Breast Cancer by Regulating the BRCA1 and p16 Genes.

BACKGROUND: Breast cancer is the most commonly diagnosed cancer and the leading cause of cancer death in females worldwide. Schleichera oleosa (kusum tree) belongs to the Sapindaceae family commonly found in many states of India. This plant is traditionally being used in various pathological conditions. METHODS: In vitro studies were performed using seed extract of Schleichera oleosa. Different concentrations of seed extracts were treated on MCF-7 breast cancer cell line and its effect on migration and colony formation were observed. BRCA1 and p16 gene expression was analyzed by real-time PCR and Western blotting. RESULTS: We have analyzed anticancer and anti-metastatic effects of seed extract in breast cancer and IC50 was 140µg/ml concentration. Further, its inhibitory role in cell migration and colony formation was at 140µg/ml (P<0.0001) concentration and reduced significantly growth of sphere at 140 µg (P<0.0031) and 150µg (P<0.0010) concentration after 5 days of treatment. The apoptosis study was shown a significant increase at 140 µg (P<0.0001) in apoptotic cells. Expression of BRCA1 and p16 were found to be over-expressed as 1.4 and 1.7 fold, respectively, at 140µg/ml concentration after 24 h of treatment at the transcription level. BRCA1 protein was up-regulated but p16 expression down-regulated at 140 to 150µg/ml (One-Way ANOVA, P<0.0001) concentration. CONCLUSION: In this study, we found a significant role of S. Oleosa seed extract has an anti-cancer as well as anti-metastatic via up-regulation of BRCA1 and p16 genes in breast cancer cells.

Development of a pH-sensitive functionalized metal organic framework: in vitro study for simultaneous delivery of doxorubicin and cyclophosphamide in breast cancer.

Exploration of an efficient dual-drug based nanocarrier with high drug loading capacity, specific targeting properties, and long-term stability is highly desirable in cancer therapy. Metal-organic frameworks (MOFs) have proven to be a promising class of drug carriers due to their high porosity, crystalline properties with defined structure information, and their potential for further functionalization. To enhance the drug efficacy as well as to overcome the burst effect of drugs, here we synthesized a pH responsive folic acid (FA) and graphene oxide (GO) decorated zeolitical imidazolate frameworks-8 (GO-FA/ZIF-8), for targeted delivery of doxorubicin (DOX) and cyclophosphamide (CP), simultaneously. In this system, DOX molecules were encapsulated in the pores of ZIF-8 during in situ synthesis of ZIF-8 and CP molecules have been captured by the GO surface via hydrogen bonding and π-π interactions as well. Furthermore, the resulting pH-responsive nanocarrier (DOX@ZIF-8/GO-FA/CP) showed in vitro sustained release characteristics (76% of DOX and 80% of CP) by cleavage of chemical bonding and disruption of the MOFs structure under acidic condition (at pH 5.6). Moreover, DOX@ZIF-8/GO-FA/CP has synergistic cytotoxic effects as compared to the combination of both the drugs without ZIF-8/GO-FA when treating MCF-7 and MDA-MB-231 breast cancer cell lines (with a combination index of 0.29 and 0.75 for MCF-7 and MDA-MB-231 cell-lines, respectively). Hence this system can be applied as an effective platform for smart dual drug delivery in breast cancer treatment through its remarkable manageable multidrug release.

p16 promoter methylation, expression, and its association with estrogen receptor, progesterone receptor, and human epidermal growth factor receptor 2 subtype of breast carcinoma.

OBJECTIVES: The purpose of the study is to investigate p16 protein expression and promoter methylation of p16 gene and their association with molecular subtypes based on parameter such as estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2). MATERIALS AND METHODS: A total of 114 breast cancer tissue biopsies were collected for methylation-specific polymerase chain reaction (MSP) and immunohistochemical (IHC) analysis. RESULTS: Seven tissue microarrays were constructed. p16 protein expression was studied in 114 cases, of which 35/114 (30.7%) cases showed strong expression and the majority of them had ER-positive tumor (57.6%), and it was statistically significant (P < 0.0074). Similarly, p16 expression was reduced in the majority of PR-negative tumors (83.9%) and the association was statistically significant (P = 0.0026). p16 methylation was studied in 114 cases and was positive in 71.0% cases. CONCLUSION: High p16 protein expression was associated with ER-positive, PR-negative, and HER2-negative tumors which is associated with poor prognosis. p16 protein expression may be used as a prognostic indicator to predict treatment response to hormonal therapy.

BRCA1 Promoter Methylation and Expression - Associations with ER+, PR+ and HER2+ Subtypes of Breast Carcinoma

Introduction: Considering the increasing trend in incidence rates, morbidity and mortality of breast cancer, there is an urgent need to identify and validate new biomarkers for early detection and better management. The purpose of the study was to investigate BRCA1 protein expression and promoter methylation of the BRCA1 gene and their association with molecular subtypes based on estrogen receptor (ER), progesterone receptor (PR) and human epidermal growth factor receptor 2 (HER2) positivity. Materials and Methods: A total of 114 breast cancer tissue biopsies were collected for methylation specific PCR (MSP) and immunohistochemical (IHC) analysis. Results: Seven tissue microarrays were constructed. BRCA1 protein expression was reduced in 55/114 (48.2%) and in the majority of ER-negative tumors (73.3%) (p<0.001). Similarly BRCA1 expression was reduced in the majority of PR-negative tumors (69.2%) but without statistical significance (p value=0.083). BRCA1 methylation was positive in 59.6% cases. A subset regarding ER+, PR+ and HER2+ was identified which consisted of 31.6% in which an inverse relationship between BRCA1 methylation and protein expression was noted. Conclusion: Reduced expression was associated with ER and PR negative status which is linked with a poor prognosis. BRCA1 protein expression might thus be used as a prognostic indicator to predict treatment response to hormone therapy.