The G-protein-coupled estrogen receptor, a gene co-expressed with ERα in breast tumors, is regulated by estrogen-ERα signalling in ERα positive breast cancer cells.

GPER is a seven transmembrane G-protein-coupled estrogen receptor that mediates rapid estrogen actions. Large volumes of data have revealed its association with clinicopathological variables in breast tumors, role in epidermal growth factor (EGF)-like effects of estrogen, potential as a therapeutic target or a prognostic marker, and involvement in endocrine resistance in the face of tamoxifen agonism. GPER cross-talks with estrogen receptor alpha (ERα) in cell culture models implicating its role in the physiology of normal or transformed mammary epithelial cells. However, discrepancies in the literature have obfuscated the nature of their relationship, its significance, and the underlying mechanism. The purpose of this study was to assess the relationship between GPER, and ERα in breast tumors, to understand the mechanistic basis, and to gauge its clinical significance. We mined The Cancer Genome Atlas (TCGA)-BRCA data to examine the relationship between GPER and ERα expression. GPER mRNA, and protein expression were analyzed in ERα-positive or -negative breast tumors from two independent cohorts using immunohistochemistry, western blotting, or RT-qPCR. The Kaplan-Meier Plotter (KM) was employed for survival analysis. The influence of estrogen in vivo was studied by examining GPER expression levels in estrus or diestrus mouse mammary tissues, and the impact of 17ß-estradiol (E2) administration in juvenile or adult mice. The effect of E2, or propylpyrazoletriol (PPT, an ERα agonist) stimulation on GPER expression was studied in MCF-7 and T47D cells, with or without tamoxifen or ERα knockdown. ERα-binding to the GPER locus was explored by analysing ChIP-seq data (ERP000380), in silico prediction of estrogen response elements, and chromatin immunoprecipitation (ChIP) assay. Clinical data revealed significant positive association between GPER and ERα expression in breast tumors. The median GPER expression in ERα-positive tumors was significantly higher than ERα-negative tumors. High GPER expression was significantly associated with longer overall survival (OS) of patients with ERα-positive tumors. In vivo experiments showed a positive effect of E2 on GPER expression. E2 induced GPER expression in MCF-7 and T47D cells; an effect mimicked by PPT. Tamoxifen or ERα-knockdown blocked the induction of GPER. Estrogen-mediated induction was associated with increased ERα occupancy in the upstream region of GPER. Furthermore, treatment with 17ß-estradiol or PPT significantly reduced the IC50 of the GPER agonist (G1)-mediated loss of MCF-7 or T47D cell viability. In conclusion, GPER is positively associated with ERα in breast tumors, and induced by estrogen-ERα signalling axis. Estrogen-mediated induction of GPER makes the cells more responsive to GPER ligands. More in-depth studies are warranted to establish the significance of GPER-ERα co-expression, and their interplay in breast tumor development, progression, and treatment.

Major chemical constituents from Illicium griffithii Hook. f. & Thoms of North East India and their cytotoxicity and antimicrobial activities.

Illicium griffithii Hook. f. & Thoms is an endemic medicinal plant of North East India found in the Eastern Himalayan region of biodiversity mega centre. Herein, chemical investigation of I. griffithii, afforded five compounds and their structures were determined through extensive use of NMR, HRMS, and FT-IR spectroscopy. The complete proton-proton, proton-carbon coupling network of compound 1 was determined using 1H-1H COSY, HSQC and NOESY NMR experiments. All the compounds were evaluated for their cytotoxic activity by MTT assay and antimicrobial activity by Agar well diffusion method. Compound 1 exhibited significant cytotoxicity activity against Lung cancer (A549) and pancreatic cancer (MIAPaCa2) cell lines with IC50 values of 15.01 ± 2.69 µg/mL and 47.77 ± 2.38 µg/mL, respectively. Further, the compound 1 exhibited good antimicrobial activities against Escherichia coli and Candida albicans with MIC 7.50 ± 0.28 µg/mL and 7.50 ± 0.86 µg/mL, respectively. The other isolated compounds along with the extracts of I. griffithii also displayed moderate anticancer and antimicrobial activities against respective strains. To the best of our knowledge, this is the first study of isolation of compounds from bark, wood, and leaf along with cytotoxicity and antimicrobial activities of I. griffithii from the North Eastern region of India and could be a potential herbal medicine in near future.

BMP4 enhances anoikis resistance and chemoresistance of breast cancer cells through canonical BMP signaling.

Bone morphogenetic proteins (BMPs) regulate cell fate during development and mediate cancer progression. In this study, we investigated the role of BMP4 in proliferation, anoikis resistance, metastatic migration, and drug resistance of breast cancer cells. We utilized breast cancer cell lines and clinical samples representing different subtypes to understand the functional effect of BMP4 on breast cancer. The BMP pathway was inhibited with the small molecule inhibitor LDN193189 hydrochloride (LDN). BMP4 signaling enhanced the expression of stem cell genes CD44, ALDH1A3, anti-apoptotic gene BCL2 and promoted anoikis resistance in MDA-MB-231 breast cancer cells. BMP4 enhanced self-renewal and chemoresistance in MDA-MB-231 by upregulating Notch signaling while LDN treatment abrogated anoikis resistance and proliferation of anoikis resistant breast cancer cells in the osteogenic microenvironment. Conversely, BMP4 downregulated proliferation, colony-forming ability, and suppressed anoikis resistance in MCF7 and SkBR3 cells, while LDN treatment promoted tumor spheroid formation and growth. These findings indicate that BMP4 has a context-dependent role in breast cancer. Further, our data with MDA-MB-231 cells representing triple-negative breast cancer suggest that BMP inhibition might impair its metastatic spread and colonization.

Chemical composition, antimicrobial activity and cytotoxicity of Murraya paniculata (L.) Jack leaf essential oil from Assam, India: the effect of oil on cellular morphology of micro-organisms.

Murraya paniculata (L.) Jack is commonly cultivated as ornamental plant in Assam and has been used as spice and phytomedicine traditionally for many healthcare purposes. The therapeutic potential and chemical constituents of the essential oil of M. paniculata leaf was investigated against several pathogenic microbial species and human cancer cell lines. 29 chemical compounds were identified by GC-MS analysis from the essential oil representing 97.62% of the oil. The major compound identified was caryophyllene (20.93%). Leaf essential oil exhibited promising antibacterial activity against Mycobacterium smegmatis (MIC = 4 µg/mL) and Pseudomonas aeruginosa (MIC = 4 µg/mL). Best anticancer activity of the oil was observed for HeLa cells (IC50 = 6.28 µg/mL). Further, scanning electron microscopic studies revealed that the oil kills micro-organisms with the deformation of cellular morphology on treatment of the oil. Thus, the essential oil of M. paniculata leaf can be an excellent alternative for development of new antimicrobials and anticancer chemotherapeutic agents for the pharmaceutical industries.

RUNX1T1, a potential prognostic marker in breast cancer, is co-ordinately expressed with ERα, and regulated by estrogen receptor signalling in breast cancer cells.

BACKGROUND: RUNX1T1 is extensively studied in the context of AML1-RUNX1T1 fusion protein in acute myeloid leukemia. Little is known about the function of RUNX1T1 itself, although data on its function and regulation have begun to emerge from clinical, and in vitro studies. It is a putative tumor suppressor, whose expression is altered in a variety of solid tumors. Recently, reduced expression of RUNX1T1 in triple-negative breast tumors, and its influence on prognosis was reported. METHODS AND RESULTS: The Kaplan-Meier Plotter online tool was used to study the relationship between RUNX1T1 expression and survival of breast cancer patients. High RUNX1T1 expression was associated with longer overall survival (OS), relapse-free survival (RFS) and distant metastasis free survival (DMFS). RUNX1T1 expression positively and negatively influenced OS of patients with ERα-positive and ERα-negative breast tumors, respectively. It was also associated with prolonged RFS, and DMFS in tamoxifen-treated patients. Expression of RUNX1T1 and ERα mRNA was analyzed in 40 breast tumor samples, and breast cancer cell lines using RT-PCR. TCGA-BRCA data was mined to study the relationship between RUNX1T1 and ERα mRNA expression. ERα-positive breast tumors showed significantly higher RUNX1T1 mRNA expression compared to ERα-negative tumors. RUNX1T1 mRNA expression was analyzed by qRT-PCR in MCF-7 or T47D cells, which were treated with 17ß-estradiol, or the ERα agonist PPT, alone or in combination with 4-hydroxytamoxifen. Effect of ERα knockdown was also investigated. Results indicate that estrogen downmodulated RUNX1T1 mRNA expression via ERα. CONCLUSION: Higher expression of RUNX1T1 in breast tumors is associated with favourable prognosis. RUNX1T1 and ERα show co-ordinated expression in breast tumors, and breast cancer cell lines. Estrogen-ERα signalling downmodulates the expression of RUNX1T1 mRNA in ERα-positive breast cancer cells. In-depth investigations on the interaction between RUNX1T1 and ERα are warranted to unravel the role and relevance of RUNX1T1 in breast cancer.

Anticancer and antimicrobial compounds from Croton caudatus Gieseler and Eurya acuminata DC: Two edible plants used in the traditional medicine of the Kuki tribes.

Eurya acuminata DC and Croton caudatus Gieseler are two ethno-medicinal plants used by Kuki community of North East India. From these plants, we have characterized fifteen phytochemicals (1-15) by extensive use of chromatographic and spectroscopic methods. They were also tested for in vitro cytotoxic effects against A549 and MIAPACA2 cell lines and antimicrobial activities against Mycobacterium smegmatis and Candida albicans. All compounds showed moderate activity against the MIAPACA2 cell lines. Compounds tricosan-1-ol (6), octacosanoic acid (7), ß-sitosterol (10) and (E)-dodec-3-en-1-ol (14) exhibited promising activity against A549 cell lines with IC50 of 16.72, 4.5, 4.42 and 4.5 µg/ml respectively. Further, hexatriacontan-1-ol (2) exhibited lowest MIC of 50 µg/ml against C. Albicans and henicosan-1-ol (3) at 25 µg/ml against M. smegmatis. They were also screened through docking analysis against two Phosphatidylinositol-3-Kinase nodal proteins and three feedback loop proteins of cancers. Thus, this study validates their traditional uses as herbal anticancer and antimicrobial agents.

Elevated expression of RUNX3 co-expressing with EZH2 in esophageal cancer patients from India.

BACKGROUND: Runt related transcription factor3 (RUNX3) is considered as a tumor suppressor gene (TSG) that functions through the TGF-ß dependent apoptosis. Promoter methylation of the CpG islands of RUNX3 and overexpression of enhancer of zeste homolog 2 (EZH2) has been suggested to downregulate RUNX3 in cancer. METHODS: Here, we studied the expression of RUNX3 and EZH2 in 58 esophageal tumors along with paired adjacent normal tissue. mRNA levels, protein expressions and cellular localizations of EZH2 and RUNX3 were analyzed using real-time PCR and immunohistochemistry, respectively. DNA methylation was further assessed by the methylation specific-PCR. RESULTS: Compared to normal tissue, a significant increase in expression of RUNX3 mRNA in 31/57 patient's tumor tissue (p < 0.04) was observed. The expression of EZH2 was found to be upregulated compared to normal, and a significant positive correlation between EZH2 and RUNX3 expression was observed (p = 0.002). 22 of the 27 unmethylated cases at the promoter region of the RUNX3 had elevated RUNX3 protein expression (p < 0.001). CONCLUSION: The data presented in this study provide new insights into the biology of RUNX3 and highlights the need to revisit our current understanding of the role of RUNX3 in cancer.

Genetic Polymorphisms Along with Dietary and Environmental Factors Enhance the Susceptibility to Nasopharyngeal Carcinoma in Nagaland of Northeast India.

This study investigated the association of seven widely known DNA repair gene polymorphisms (hOGG1 Ser326Cys, XRCC1 Arg194Trp, XRCC1 Arg280His, XRCC1 Arg399Gln, XPC Val499Ala, XPD Lys751Gln and ERCC1 Cys8092Ala) with dietary and environmental factors for Nasopharyngeal Carcinoma (NPC) susceptibility in Nagaland of Northeast India. The genotypes were determined in 128 NPC patients and 180 healthy controls by PCR-RFLP. XRCC1 Arg280His, XPC Val499Ala and ERCC1 Cys8092Ala were found to be associated with NPC risk. Tobacco smoking and burning of firewood for cooking were also found to be a risk factor for NPC. The haplotype analysis of five single-nucleotide polymorphisms (SNPs) XRCC1 Arg194Trp, XRCC1 Arg280His, XRCC1 Arg399Gln, XPD Lys751Gln and ERCC1 Cys8092Ala identified haplotype TGAAC to be significantly associated with NPC. Multifactor dimensionality reduction (MDR) analysis suggested ERCC1 Cys8092Ala to be the best one-factor model that could predict NPC risk. From this study, we conclude that examining the synergistic interactions of various gene-environmental factors together is a better approach to understand NPC susceptibility, instead of their individual effects.

IL-10 Polymorphisms and Haplotypes Predict Susceptibility to Hepatocellular Carcinoma Occurrence in Patients with Hepatitis C Virus Infection from Northeast India.

Chronic hepatitis C virus (HCV) infection leads to variable outcomes, ranging from prolonged slow hepatic damage leading to cirrhosis, and hepatocellular carcinoma (HCC). Polymorphism in cytokines IL-10 and IL-12 that impact the immune response to HCV infection may play a role in determining this outcome. This study was aimed to determine if polymorphisms in IL-10 and IL-12B contribute to HCV susceptibility and the risk of developing HCC in patients from Northeast India. IL-10 - 1082, -819, -592 polymorphisms and IL-12B -1188 polymorphisms were genotyped by polymerase chain reaction-restriction fragment length polymorphism in a total of 266 HCV-infected patients and 100 age- and sex-matched controls. In the HCV-infected subjects, 110 patients had chronic hepatitis C (CHC), 96 with liver cirrhosis, and 60 with HCC. Serum levels of IL-10 were also measured and correlated with disease severity. Haplotype analysis for IL-10 polymorphisms was carried out. Statistical data were analyzed using SPSS ver. 22.0. The frequency of IL-10 - 592 AA genotype/A allele was significantly higher in HCC patients than in CHC patients. The intermediate IL-10-producing ACC haplotype was significantly more frequent in HCC and cirrhotic patients than in CHC patients. No significant association was found for IL-10 - 819, -592 and IL-12B -1188 polymorphisms with the susceptibility to HCV infection or occurrence of HCC in HCV-infected patients. IL-10 - 592 CA polymorphism and IL-10 ACC haplotype are significant biomarkers of HCC in HCV-infected patients from Northeast India. Higher serum levels of IL-10 were also linked to higher disease severity.

Role of VDR, GC, and CYP2R1 Polymorphisms in the Development of Hepatocellular Carcinoma in Hepatitis C Virus-Infected Patients.

Aims: This study was designed to determine if vitamin D receptor (VDR), carrier globulin/binding protein (GC), and cytochrome P-450 family 2, subfamily R, polypeptide 1 (CYP2R1) gene polymorphisms are risk factors in the development of hepatocellular carcinoma (HCC) in hepatitis C virus (HCV)-infected patients from Northeast India. Materials and Methods: A total of 351 HCV-infected patients were enrolled of which 167 were diagnosed with chronic hepatitis C (CHC), 124 with liver cirrhosis (LC), and 60 with HCC together with 102 age- and sex-matched healthy controls. VDR (BsmI, ApaI, and TaqI), GC (rs4588, rs7051), and CYP2R1 (rs10741657) gene polymorphisms were genotyped for all subjects. Statistical data were analyzed using SPSS ver. 22.0. Results: The frequency of the ApaI CC genotype, ApaI C allele, and bAt haplotype of the VDR gene was significantly higher in HCC and LC patients than controls. After adjusting for other covariates (age, gender, platelet count, AST, ALT, serum albumin, and viral load) logistic regression analysis showed that the ApaI CC genotype and bAt haplotype were independent predictors of HCC development. No significant associations was found for the GC and CYP2R1 polymorphisms examined with the occurrence of HCC. Conclusions: The presence of the VDR ApaI CC genotype and bAt haplotype appear to be important indicators in the development of HCC among HCV-infected patients. Larger studies are needed to further clarify and establish this potential causal relationship.

Decreased expression of MGMT in correlation with aberrant DNA methylation in esophageal cancer patients from North India.

O-6-methylguanine-DNA methyltransferase, DNA repair gene, has been found to be involved with the pathogenesis of the esophageal cancer. DNA hypermethylation and other factors have been suggested to downregulate O-6-methylguanine-DNA methyltransferase. In this communication, the methylation status of O-6-methylguanine-DNA methyltransferase gene and the corresponding O-6-methylguanine-DNA methyltransferase protein expression in esophageal cancer from North India has been studied. In all, 80 samples of tumor tissue along with adjacent normal tissue as controls were analyzed for messenger RNA level of O-6-methylguanine-DNA methyltransferase gene, protein expression, and subcellular localization. The messenger RNA expression was studied using real-time quantitative polymerase chain reaction, protein expression, and its subcellular localization by Western blotting and immunohistochemistry. DNA methylation was assessed through methylation-specific polymerase chain reaction. Clinicopathological parameters were recorded and correlated with the O-6-methylguanine-DNA methyltransferase expression. O-6-methylguanine-DNA methyltransferase messenger RNA expression was found to be downregulated in 65% cases (52/80). The expression of O-6-methylguanine-DNA methyltransferase at the protein level was also found to be absent in 65% (52/80) cases. In all, 52 cases had low or no expression of the protein, whereas out of those 28 remaining cases, 11.25% (09/80) cases had high O-6-methylguanine-DNA methyltransferase protein expression. The absence of O-6-methylguanine-DNA methyltransferase protein coincided with the methylated cases in 84% (38/45), whereas in 07 cases, out of the 45 methylated, O-6-methylguanine-DNA methyltransferase protein was present. The aggressive esophageal cancer patients having methylated O-6-methylguanine-DNA methyltransferase had more than 50% cases with no/mild expression of the O-6-methylguanine-DNA methyltransferase protein ( p > 0.001). Loss of O-6-methylguanine-DNA methyltransferase protein was very frequent in the incidence of esophageal cancer from North Indian patients, and methylation of the promoter region of O-6-methylguanine-DNA methyltransferase was significantly associated in its downregulation.

Alteration in the expression of MGMT and RUNX3 due to non-CpG promoter methylation and their correlation with different risk factors in esophageal cancer patients.

Promoter methylation reflects in the inactivation of different genes like O6-methylguanine-DNA methyltransferase DNA repair gene and runt-related transcription factor 3, a known tumor suppressor gene in various cancers such as esophageal cancer. The promoter methylation was evaluated for O6-methylguanine-DNA methyltransferase and runt-related transcription factor 3 in CpG, CHH, and CHG context (where H is A, T, or C) by next-generation sequencing. The methylation status was correlated with quantitative messenger RNA expression. In addition, messenger RNA expression was correlated with different risk factors like tobacco, alcohol, betel nut consumption, and smoking habit. CpG methylation of O6-methylguanine-DNA methyltransferase promoter had a positive association in the development of esophageal cancer (p < 0.05), whereas runt-related transcription factor 3 promoter methylation showed no significant association (p = 1.0) to develop esophageal cancer. However, the non-CpG methylation, CHH, and CHG were significantly correlated with O6-methylguanine-DNA methyltransferase (p < 0.05) and runt-related transcription factor 3 (p < 0.05) promoters in the development of esophageal cancer. The number of cytosine converted to thymine (C→T) in O6-methylguanine-DNA methyltransferase promoter showed a significant correlation between cases and controls (p < 0.05), but in runt-related transcription factor 3 no such significant correlation was observed. Besides, messenger RNA expression was found to be significantly correlated with promoter hypermethylation of O6-methylguanine-DNA methyltransferase and runt-related transcription factor 3 in the context of CHG and CHH (p < 0.05). The CpG hypermethylation in O6-methylguanine-DNA methyltransferase showed positive (p < 0.05) association, whereas in runt-related transcription factor 3, it showed contrasting negative association (p = 0.23) with their messenger RNA expression. Tobacco, betel nut consumption, and smoking habits were associated with altered messenger RNA expression of O6-methylguanine-DNA methyltransferase (p < 0.05) and betel nut consumption and smoking habits were associated with runt-related transcription factor 3 (p < 0.05). There was no significant association between messenger RNA expression of O6-methylguanine-DNA methyltransferase and runt-related transcription factor 3 with alcohol consumption (p = 0.32 and p = 0.15). In conclusion, our results suggest that an aberrant messenger RNA expression may be the outcome of CpG, CHG, and CHH methylation in O6-methylguanine-DNA methyltransferase, whereas outcome of CHG and CHH methylation in runt-related transcription factor 3 promoters along with risk factors such as consumption of tobacco, betel nut, and smoking habits in esophageal cancer from Northeast India.

Polymorphisms in Heat Shock Proteins A1B and A1L (HOM) as Risk Factors for Oesophageal Carcinoma in Northeast India.

BACKGROUND: To investigate polymorphisms in heat shock proteins A1B and A1L (HOM) and associated risk of oesophageal carcinoma in Northeast India. MATERIALS AND METHODS: The study includes oesophageal cancer (ECA) patients attending general outpatient department (OPD) and endoscopic unit of Gauhati Medical College. Patients were diagnosed based on endoscopic and histopathological findings. Genomic DNA was typed for HSPA1B1267 and HSPA1L2437 SNPs using the polymerase chain reaction with restriction fragment length polymorphisms. RESULTS: A total of 78 cases and 100 age-sex matched healthy controls were included in the study with a male: female ratio of 5:3 and a mean age of 61.4±8.5 years. Clinico-pathological evaluation showed 84% had squamous cell carcinoma and 16% were adenocarcinoma. Dysphagia grades 4 (43.5%) and 5 (37.1%) were observed by endoscopic and hispathological evaluation. The frequency of genomic variation of A1B from wild type A/A to heterozygous A/G and mutant G/G showed a positive association [chi sq=19.9, p= <0.05] and the allelic frequency also showed a significant correlation [chi sq=10.3, with cases vs. controls, OR=0.32, p≤0.05]. The genomic variation of A1L from wild T/T to heterozygous T/C and mutant C/C were found positively associated [chi sq= 7.02, p<0.05] with development of ECA. While analyzing the allelic frequency, there was no significant association [chi sq= 3.19, OR=0.49, p=0.07]. Among all the risk factors, betel quid [OR =9.79, Chi square= 35.0, p<0.05], tobacco [OR = 2.95, chi square=10.6, p<0.05], smoking [OR=3.23, chi square=10.1, p<0.05] demonstrated significant differences between consumers vs. non consumers regarding EC development. Alcohol did not show any significant association [OR= 1.34, chi square=0.69, p=0.4] independently. CONCLUSIONS: It can be concluded that the present study provides marked evidence that polymorphisms of HSP70 A1B and HSP70 A1L genes are associated with the development of ECA in a population in Northeast India, A1B having a stronger influence. Betel quid consumption was found to be a highly significant risk factor, followed by smoking and tobacco chewing. Although alcohol was not a potent risk factor independently, alcohol consumption along with tobacco, smoking and betel nut was found to contribute to development of ECA.