Associations between the Levels of Estradiol-, Progesterone-, and Testosterone-Sensitive MiRNAs and Main Clinicopathologic Features of Breast Cancer

Abstract

Despite the existing advances in the diagnosis and treatment of breast cancer (BC), the search for markers associated with the clinicopathological features of BC is still in demand. MiRNAs (miRs) have potential as markers, since a change in the miRNA expression profile accompanies the initiation and progression of malignant diseases. The receptors for estrogen, androgen, and progesterone (ER, AR, and PR) play an important role in breast carcinogenesis. Therefore, to search for miRNAs that may function as markers in BC, using bioinformatic analysis and the literature data, we selected 13 miRNAs whose promoter regions contain binding sites for ER or AR, or putative binding sites for ER, AR, and PR. We quantified their expression in MCF-7 cells treated with estradiol, progesterone, or testosterone. The levels of miRNAs sensitive to one or more of these hormones were quantified in BC samples (n = 196). We discovered that high expression levels of miR-190b in breast tumor tissue indicate a positive ER status, and miR-423 and miR-200b levels differ between patients with and without HER2 amplification. The miR-193b, -423, -190a, -324, and -200b levels were associated with tumor size or lymph node status in BC patients, but the presence of these associations depended on the status and expression level of ER, PR, HER2, and Ki-67. We also found that miR-21 expression depends on HER2 expression in ER- and/or PR-positive BC. The levels of miRNA were significantly different between HER2 0 and HER2 1+ tumors (p = 0.027), and between HER2 0 and HER2 2+, 3+ tumors (p = 0.005).

Keywords: biomarker; breast cancer; hormone-dependent carcinogenesis; lymph node metastasis; microRNA.

Figure 1

The comparison of miRNA expression between normal and cancerous tissue groups. The Y axis presents the expression level ($${\log }_2{2}^{–\mathsf{\Delta }\mathsf{\Delta }\mathrm{Ct}}$$).

Figure 2

The comparison of miR-190a expression between different cancerous tissue groups: (A) relation of miR-190a level with the LNM in tumors with Ki-67 < 14% (left), relation of miR-190a level with the LNM in tumors with Ki-67 ≥ 14% (right); (B) relation of miR-190a level with the PR expression level in tumors with Ki-67 ≥ 14% (left), relation of miR-190a level with the PR expression level in tumors with Ki-67 < 14% (right); (C) relation of miR-190a level with age of patients with luminal B HER2-aplified BC. The Y axis presents the expression level ($${\log }_2{2}^{–\mathsf{\Delta }\mathsf{\Delta }\mathrm{Ct}}$$); the results were normalized to the control (normal tissue).

Figure 3

The comparison of miR-190b expression between different cancerous tissue groups: (A) relation of miR-190b level with the LNM in tumors with HER2 IHC score 0 (left), relation of miR-190b level with the LNM in tumors with HER2 IHC score 1+, 2+, 3+ (right); (B) relation of miR-190b level with Ki-67 in tissues of patients with luminal HER2-expressing BC (20% was the median value of Ki-67 index). The Y axis presents the expression level ($${\log }_2{2}^{–\mathsf{\Delta }\mathsf{\Delta }\mathrm{Ct}}$$); the results were normalized to the control (normal tissue).

Figure 4

Relation of miR-27a level with PR expression level in luminal B tumors (left) and relation of miR-27a level with PR expression level in luminal A tumors (right). The Y axis presents the expression level ($${\log }_2{2}^{–\mathsf{\Delta }\mathsf{\Delta }\mathrm{Ct}}$$); the results were normalized to the control (normal tissue).

Figure 5

The comparison of miR-193b expression between different cancerous tissue groups: (A) relation of miR-193b level with the T stage in tumors with HER2 IHC score 0 (left), relation of miR-193b level with the T stage in tumors with HER2 IHC score 1+, 2+, 3+ (right); (B) relation of miR-193b level with LNM in tumors with HER2 IHC score 0, 2+, 3+ (left), relation of miR-193b level with LNM in tumors with HER2 IHC score 1+ (right); (C) relation of miR-193b level with PR and ER expression levels in luminal B HER2 0 BC. The Y axis presents the expression level ($${\log }_2{2}^{–\mathsf{\Delta }\mathsf{\Delta }\mathrm{Ct}}$$); the results were normalized to the control (normal tissue).

Figure 6

The comparison of miR-324 expression between different cancerous tissue groups: (A) relation of miR-324 level with the T stage in luminal B HER2-non-amplified tumors (left), relation of miR-324 level with the T stage in luminal A and luminal B HER2-amplified tumors (right); (B) relation of miR-324 level with age of patients in tumors with Ki-67 < 14% (left), relation of miR-324 level with age of patients in tumors with Ki-67 ≥ 14% (right). The Y axis presents the expression level ($${\log }_2{2}^{–\mathsf{\Delta }\mathsf{\Delta }\mathrm{Ct}}$$); the results were normalized to the control (normal tissue).

Figure 7

Relation of miR-423 level with LNM in luminal A, luminal B HER2-amplified, and luminal B HER2 1+ tumors (left); relation of miR-423 level with LNM in luminal B HER2-non-expressing tumors (right). The Y axis presents the expression level ($${\log }_2{2}^{–\mathsf{\Delta }\mathsf{\Delta }\mathrm{Ct}}$$); the results were normalized to the control (normal tissue).

Figure 8

The comparison of miR-200b expression between different cancerous tissue groups: (A) relation of miR-200b level with the T stage in tumors with Ki-67 < 14% (left), relation of miR-200b level with the T stage in tumors with Ki-67 ≥ 14% (right); (B) relation of miR-200b level with ER expression level in luminal B HER2-non-expressing tumors. The Y axis presents the expression level ($${\log }_2{2}^{–\mathsf{\Delta }\mathsf{\Delta }\mathrm{Ct}}$$); the results were normalized to the control (normal tissue).

Figure 9

The comparison of miR-21 expression between different cancerous tissue groups: (A) relation of miR-21 level with LNM in HER2-expressing tumors with Ki-67 ≥ 14% (left), relation of miR-21 level with LNM in HER2-expressing tumors with Ki-67 < 14% (right); (B) relation of miR-21 level with PR expression level in luminal B HER2-non-expressing tumors. The Y axis presents the expression level ($${\log }_2{2}^{–\mathsf{\Delta }\mathsf{\Delta }\mathrm{Ct}}$$); the results were normalized to the control (normal tissue).

Figure 10

The relation of the miR-21 level with the HER2 expression level in ER-positive and/or PR-positive tumors. The Y axis presents the expression level ($${\log }_2{2}^{–\mathsf{\Delta }\mathsf{\Delta }\mathrm{Ct}}$$); the results were normalized to the control (normal tissue).

Figure 11

The comparison of miR-21 expression between different BC subtypes. HER2+ = HER2 amplification. Tumors with HER2 IHC scores of 1+ were treated as a separate group. The Y axis presents the expression level ($${\log }_2{2}^{–\mathsf{\Delta }\mathsf{\Delta }\mathrm{Ct}}$$); the results were normalized to the control (normal tissue).

Figure 12

The comparison of miR-190a, miR-190b, and miR-27a expression between different cancerous tissue groups: (A) relation of miR-190a level with Ki-67 index in TNBC (75% was the median value of Ki-67); (B) relation of miR-190b level with Ki-67 in HER2-amplified tumors (32% was the median value of Ki-67); (C) relation of miR-27a level with age of patients with HER2-expressing tumors. The Y axis presents the expression level ($${\log }_2{2}^{–\mathsf{\Delta }\mathsf{\Delta }\mathrm{Ct}}$$); the results were normalized to the control (normal tissue).