Anti-ESR1 monoclonal antibody, clone 3H223C4

Objective: This study aimed to investigate the role of ESR1 and PGR gene polymorphisms in development of intrauterine growth restriction (IUGR) among Russian women in Central Russia. Study design: This case-control study recruited a total of 520 women in the third trimester of pregnancy, including 196 IUGR patients and 324 controls. The participants were unrelated women of self-reported Russian ethnicity. Participants were genotyped at 4 functionally significant polymorphisms of the ESR1 (rs2234693, rs9340799) and the PGR (rs484389, rs1042838) genes. The association analysis was performed using logistic regression. Two polymorphisms, which were associated with IUGR, and 26 polymorphisms linked to them (r(2) >= 0.6) were analyzed for their functional significance in silico. Results: Haplotype TG of loci rs2234693-rs9340799ESR1 (OR = 1.94, P-perm = 0.006) was associated with an increased risk of IUGR. Allele T of rs2234693 decreases expression of ESR1 in thyroid gland, allele T of rs2234693 and allele G of rs9340799 increase affinity to eight transcription factors (AP-4, HEN1, E2A, LBP-1, RP58, LUN, Ets and Hand). The loci that are linked (r(2) >= 0.6) to the IUGR-associated SNPs, have the cis-eQTL value (expression ESR1 in thyroid gland) and showed their regulatory effects in organs and tissues related to pathogenesis of IUGR. Conclusion: Haplotype TG defined by polymorphisms rs2234693-rs9340799 of the ESR1 gene is associated with the development of IUGR in Russian women from Central Russia. (C) 2020 Elsevier B.V. All rights reserved.

Mechanisms driving resistance to cyclin-dependent kinase 4/6 inhibitors (CDK4/6i) in hormone receptor-positive (HR+) breast cancer have not been clearly defined. Whole-exome sequencing of 59 tumors with CDK4/6i exposure revealed multiple candidate resistance mechanisms including RB1 loss, activating alterations in AKT1, RAS, AURKA, CCNE2, ERBB2, and FGFR2, and loss of estrogen receptor expression. in vitro experiments confirmed that these alterations conferred CDK4/6i resistance. Cancer cells cultured to resistance with CDK4/6i also acquired RB1, KRAS, AURKA, or CCNE2 alterations, which conferred sensitivity to AURKA, ERK, or CHEK1 inhibition. Three of these activating alterations-in AKT1, RAS, and AURKA-have not, to our knowledge, been previously demonstrated as mechanisms of resistance to CDK4/6i in breast cancer preclinically or in patient samples. Together, these eight mechanisms were present in 66% of resistant tumors profiled and may define therapeutic opportunities in patients. SIGNIFICANCE: We identified eight distinct mechanisms of resistance to CDK4/6i present in 66% of resistant tumors profiled. Most of these have a therapeutic strategy to overcome or prevent resistance in these tumors. Taken together, these findings have critical implications related to the potential utility of precision-based approaches to overcome resistance in many patients with HR- metastatic breast cancer.