Downregulation of microRNA‑183‑5p inhibits the proliferation and invasion of colorectal cancer cells by inactivating the reticulocalbin‑2/Wnt/β‑catenin signaling pathway

Regulatory RNAs, microRNA, long-non coding RNA and circular RNA roles in colorectal cancer stem cells

The properties of cancer stem cells (CSCs), such as self-renewal, drug resistance, and metastasis, have been indicated to be responsible for the poor prognosis of patients with colon cancers. The epigenetic regulatory network plays a crucial role in CSC properties. Regulatory non-coding RNA (ncRNA), including microRNAs, long noncoding RNAs, and circular RNAs, have an important influence on cell physiopathology. They modulate cells by regulating gene expression in different ways. This review discusses the basic characteristics and the physiological functions of colorectal cancer (CRC) stem cells. Elucidation of these ncRNAs will help us understand the pathological mechanism of CRC progression, and they could become a new target for cancer treatment.

Long non-coding RNA DUXAP8 elevates RCN2 expression and facilitates cell malignant behaviors and angiogenesis in cervical cancer via sponging miR-1297

BACKGROUND

Cervical cancer (CC) endangers women's health in the world range. Accumulating studies have revealed the crucial regulatory role of long non-coding RNAs (lncRNAs) in multiple malignancies, including CC. Our study aimed to explore the role of lncRNA double homeobox A pseudogene 8 (DUXAP8) in cervical carcinogenesis.

METHODS

Gene expressions in CC were assessed by RT-qPCR. Function experiments and tube formation assays were performed to evaluate the role of DUXAP8 in CC cells. Subcellular fractionation and FISH assays were conducted to determine the subcellular location of DUXAP8. Luciferase reporter, RNA pull down and RIP assays were conducted to investigate the mechanism of DUXAP8.

RESULTS

DUXAP8 was notably upregulated in CC cells. Downregulation of DUXAP8 repressed cell malignant behaviors and angiogenesis in CC. Mechanically, DUXAP8 boosted the expression of reticulocalbin-2 (RCN2) through relieving the binding of miR-1297 to RCN2 3'-UTR. Moreover, miR-1297 inhibition and RCN2 overexpression could counteract the inhibitory effects of DUXAP8 knockdown on the malignant phenotypes of CC cells. Besides, enhanced RCN2 expression restored the tumor growth in vivo that was inhibited by DUXAP8 repression.

CONCLUSIONS

DUXAP8 promotes malignant behaviors in CC cells via regulating miR-1297/RCN2 axis.

Wnt-Signaling Regulated by Glucocorticoid-Induced miRNAs

Glucocorticoids (GCs) are pleiotropic hormones which regulate innumerable physiological processes. Their comprehensive effects are due to the diversity of signaling mechanism networks. MiRNAs, small, non-coding RNAs contribute to the fine tuning of signaling pathways and reciprocal regulation between GCs and miRNAs has been suggested. Our aim was to investigate the expressional change and potential function of GC mediated miRNAs. The miRNA expression profile was measured in three models: human adrenocortical adenoma vs. normal tissue, steroid-producing H295R cells and in hormonally inactive HeLa cells before and after dexamethasone treatment. The gene expression profile in 82 control and 57 GC-affected samples was evaluated in GC producing and six different GC target tissue types. Tissue-specific target prediction (TSTP) was applied to identify the most relevant miRNA-mRNA interactions. Glucocorticoid treatment resulted in cell type-dependent miRNA expression changes. However, 19.5% of the influenced signaling pathways were common in all three experiments, of which the Wnt-signaling pathway seemed to be the most affected. Transcriptome data and TSTP showed similar results, as the Wnt pathway was significantly altered in both the GC-producing adrenal gland and all investigated GC target tissue types. In different cell types, different miRNAs led to the regulation of similar pathways. Wnt signaling may be one of the most important signaling pathways affected by hypercortisolism. It is, at least in part, regulated by miRNAs that mediate the glucocorticoid effect. Our findings on GC producing and GC target tissues suggest that the alteration of Wnt signaling (together with other pathways) may be responsible for the leading symptoms observed in Cushing's syndrome.

The Combination Therapy of Fluorouracil and Oxaliplatin Suppress the Progression of Colon Cancer Through miR-183-5p/SOCS3 Axis and Downregulating PD-L1

Purpose

The purpose of this study was to investigate the mechanism of combination of fluorouracil (FU) and oxaliplatin (OXA) on the progression of colon cancer via miR-183-5p/SOCS3 axis and regulating PD-L1.

Methods

HCT116 cells were treated with 4 μM OXA and 10.5 μM FU, or exogenous regulation of the expression of miR-183-5p, SOCS3 and PD-L1 in HCT116 cells. CCK-8 assay was employed to detect cell viability of HCT116 cells. Flow cytometry was performed to assess the apoptosis and cell cycle. The expression level of SOCS3, PD-L1, chemokines (CCL1, CCL4 and CCL7) and immune escapes related proteins (EGFR, STARD1 and STARD3) in HCT116 cells were assessed by Western blotting. In addition, dual-luciferase reporter gene was carried out to verify the targeted relationship between miR-183-5p with SOCS3.

Results

Our study demonstrated that the combination of OXA and FU remarkably suppressed proliferation, promoted apoptosis and arrest cells in G0/G1 phrase of HCT116 cells, and observably downregulated the expression of PD-L1, CCL1, CCL4, CCL7, EGFR, STARD1 and STARD3. Meanwhile, the combination of OXA and FU significantly downregulated miR-183-5p expression. Knockdown of miR-183-5p also repressed the proliferation, promoted apoptosis and arrest cells in G0/G1 phrase of HCT116 cells, and downregulated the expression of PD-L1, CCL1, CCL4, CCL7, EGFR, STARD1 and STARD3. In addition, our study proved that miR-183-5p upregulated PD-L1 by targeting downregulated SOCS3 expression. Finally, we demonstrated that the combination therapy of OXA and FU inhibited the proliferation, promote apoptosis and arrest cells in G0/G1 phrase by downregulating PD-L1 via miR-183-5p/SOCS3 axis.

Conclusion

The combination therapy of OXA and FU could suppress the malignant biological behavior, and the mechanism was realized by inhibiting PD-L1 through miR-183-5p/SOCS3 axis.