MiR-18a 在 ER 阳性乳腺癌中激活 Wnt 通路，与不良预后相关。
- 作者列表："Nair MG","Prabhu JS","Korlimarla A","Rajarajan S","P S H","Kaul R","Alexander A","Raghavan R","B S S","T S S
:Despite the established benefits of long-term endocrine therapy, women with hormone receptor-positive breast cancer remain at risk for late relapse. The basis of this is multi-factorial including genetic, epigenetic, and host factors. In this study we have explored the epigenetic regulation of estrogen receptor (ER)-dependent molecular and cellular phenotype by hsa-miR-18a-5p using well-established human ER-positive (ER+) breast cancer cell lines. miR-18a was overexpressed in MCF7 and ZR-75-1 and this led to an increase in the proliferative ability of the cells and concurrently resulted in decreased expression of luminal markers and higher expression of the basal marker, cytokeratin 14. The cells became more migratory with a significant repression of E-cadherin and activation of the Wnt noncanonical pathway. We observed an activation of the planar cell polarity (PCP) pathway with increased activation of JNK pathway and eventually change in actin dynamics. There was increased F-actin polymerization in cells with higher expression of miR-18a. Examination of miR-18a expression in a set of human ER+ breast cancer specimens showed a negative correlation between miR-18a and ESR1 transcripts as well as ER protein. Kaplan-Meier survival analysis of the cohort stratified by tumor hsa-miR-18a-5p levels produced significant differences in disease-free survival (log rank P < .05). This observation was independently validated in the METABRIC cohort. These data provide support for a role of hsa-miR-18a-5p in altering the proliferative and migratory behavior of ER+ cells and its potential utility as a prognostic marker in clinical ER+ breast cancers.
: 尽管长期内分泌治疗已确立了益处，但激素受体阳性乳腺癌女性仍有晚期复发的风险。其基础是多因素的，包括遗传、表观遗传和宿主因素。在这项研究中，我们探索了雌激素受体 (ER) 依赖的分子和细胞表型的表观遗传调控，通过使用成熟的人 ER 阳性 (ER +) 乳腺癌细胞系 hsa-miR-18a-5p。MiR-18a 在 MCF7 和 ZR-75-1 中过表达，这导致细胞增殖能力的增加，同时导致管腔标记物的表达减少和基础标记物细胞角蛋白 14 的表达增加。细胞变得更加迁移，E-cadherin 显著抑制，Wnt 非经典通路激活。我们观察到平面细胞极性 (PCP) 通路的激活与 JNK 通路的激活增加，最终改变肌动蛋白动力学。细胞中 F-肌动蛋白聚合增加，miR-18a 表达增加。在一组人 ER + 乳腺癌标本中检测 miR-18a 表达显示 miR-18a 与 ESR1 转录本以及 ER 蛋白之间呈负相关。按肿瘤 hsa-miR-18a-5p 水平分层的队列 Kaplan-Meier 生存分析在无病生存方面产生显著差异 (log rank P <.05)。该观察结果在代谢队列中独立验证。这些数据支持 hsa-miR-18a-5p 在改变 ER + 细胞增殖和迁移行为中的作用及其作为临床 ER + 乳腺癌预后标志物的潜在效用。
METHODS::The emerging significance of the bitter taste receptors (T2Rs) role in the extraoral tissues alludes to their potential role in many pathophysiological conditions. The dysregulation of T2R expression and function in disease conditions has now been demonstrated in airways diseases, neurological disorders, and in some cancers. However, the role of T2Rs in the pathophysiology of breast cancer is unexplored thus far. Previously, we demonstrated differential expression of the 25 T2Rs in breast cancer (BC) cells. Based on our previous findings we selected two T2Rs, T2R4 and T2R14 for this work. The objective of the current study is to investigate the expression of T2R4 and T2R14 in BC clinical samples and to examine their physiological role using highly metastatic BC and non-cancerous cell lines. Using approaches, which involve receptor knockdown, pharmacological activation and biochemical assays we report that (i) T2R4 and T2R14 expression patterns are dissimilar, with decreased levels of T2R4 and increased levels of T2R14 in BC clinical samples compared to non-cancerous controls. (ii) Activation of T2Rs with their respective agonist elicited physiological responses in metastatic breast cancer cells, and no responses were seen in non-tumorigenic breast epithelial cells. (iii) Agonist activation of T2Rs (irrespective of T2R subtype) induced anti-proliferative, pro-apoptotic, and anti-migratory responses in highly metastatic breast cancer cells. Taken together, our findings demonstrate that the chemosensory T2R signaling network is involved in evoking physiological responses in the metastatic breast cancer cell line.
METHODS::RAD50 is commonly depleted in basal-like breast cancer with concomitant absence of INPP4B and several tumor suppressors such as BRCA1 and TP53. Our previous study revealed that INPP4B and RAD50 interact and such an interaction is associated with breast cancer survival at the transcriptional, translational and genomic levels. In the present study, we explored single nucleotide polymorphisms (SNPs) of these two genes that have synergistic effects on breast cancer survival to decipher mechanisms driving their interactions at the genetic level. The Cox's proportional hazards model was used to test whether SNPs of these two genes are interactively associated with breast cancer survival, following expression quantitative trait loci (eQTL) analysis and functional investigations. Our study revealed two disease-associating blocks, each encompassing five and two non-linkage disequilibrium linked SNPs of INPP4B and RAD50, respectively. Concomitant presence of any rare homozygote from each disease-associating block is synergistically prognostic of poor breast cancer survival. Such synergy is mediated via bypassing pathways controlling cell proliferation and DNA damage repair, which are represented by INPP4B and RAD50. Our study provided genetic evidence of interactions between INPP4B and RAD50, and deepened our understandings on the orchestrated genetic machinery governing tumor progression.
METHODS:BACKGROUND:Increased usage of genomic risk assessment assays suggests increased reliance on data provided by these assays to guide therapy decisions. The current study aimed to assess the change in treatment decision and physician confidence based on the 70-gene risk of recurrence signature (70-GS, MammaPrint) and the 80-gene molecular subtype signature (80-GS, BluePrint) in early stage breast cancer patients. METHODS:IMPACt, a prospective, case-only study, enrolled 452 patients between November 2015 and August 2017. The primary objective population included 358 patients with stage I-II, hormone receptor-positive, HER2-negative breast cancer. The recommended treatment plan and physician confidence were captured before and after receiving results for 70-GS and 80-GS. Treatment was started after obtaining results. The distribution of 70-GS High Risk (HR) and Low Risk (LR) patients was evaluated, in addition to the distribution of 80-GS compared to IHC status. RESULTS:The 70-GS classified 62.5% (n = 224/358) of patients as LR and 37.5% (n = 134/358) as HR. Treatment decisions were changed for 24.0% (n = 86/358) of patients after receiving 70-GS and 80-GS results. Of the LR patients initially prescribed CT, 71.0% (44/62) had CT removed from their treatment recommendation. Of the HR patients not initially prescribed CT, 65.1% (41/63) had CT added. After receiving 70-GS results, CT was included in 83.6% (n = 112/134) of 70-GS HR patient treatment plans, and 91.5% (n = 205/224) of 70-GS LR patient treatment plans did not include CT. For patients who disagreed with the treatment recommended by their physicians, most (94.1%, n = 16/17) elected not to receive CT when it was recommended. For patients whose physician-recommended treatment plan was discordant with 70-GS results, discordance was significantly associated with age and lymph node status. CONCLUSIONS:The IMPACt trial showed that treatment plans were 88.5% (n = 317/358) in agreement with 70-GS results, indicating that physicians make treatment decisions in clinical practice based on the 70-GS result. In clinically high risk, 70-GS Low Risk patients, there was a 60.0% reduction in treatment recommendations that include CT. Additionally, physicians reported having greater confidence in treatment decisions for their patients in 72% (n = 258/358) of cases after receiving 70-GS results. TRIAL REGISTRATION:"Measuring the Impact of MammaPrint on Adjuvant and Neoadjuvant Treatment in Breast Cancer Patients: A Prospective Registry" (NCT02670577) retrospectively registered on Jan 27, 2016.