MicroRNA-188 inhibits biological activity of lung cancer stem cells through targeting MDK and mediating the Hippo pathway

Interaction of noncoding RNAs with hippo signaling pathway in cancer cells and cancer stem cells

The Hippo signaling pathway has a regulatory function in the organogenesis process and cellular homeostasis, switching the cascade reactions of crucial kinases acts to turn off/on the Hippo pathway, altering the downstream gene expression and thereby regulating proliferation, apoptosis, or stemness. Disruption of this pathway can lead to the occurrence of various disorders and different types of cancer. Recent findings highlight the importance of ncRNAs, such as microRNA, circular RNA, and lncRNAs, in modulating the Hippo pathway. Defects in ncRNAs can disrupt Hippo pathway balance, increasing tumor cells, tumorigenesis, and chemotherapeutic resistance. This review summarizes ncRNAs' inhibitory or stimulatory role in - Hippo pathway regulation in cancer and stem cells. Identifying the relation between ncRNAs and the components of this pathway could pave the way for developing new biomarkers in the treatment and diagnosis of cancers.

Deciphering the role of Hippo pathway in lung cancer

Hippo pathway has been initially recognized as a regulatory mechanism for modulation of organ size in fruitfly. Subsequently, its involvement in the regulation of homeostasis and tumorigenesis has been identified. This pathway contains some tumor suppressor genes such as hippo (hpo) and warts (wts), as well as a number of oncogenic ones such as yorkie (yki). Recent studies have shown participation of Hippo pathway in the lung carcinogenesis. This pathway can affect lung cancer via different mechanisms. The interaction between some miRNAs and Hippo pathway is a possible mechanism for carcinogenic processes. Moreover, some other types of non-coding RNAs including PVT1, SFTA1P, NSCLCAT1 and circ_0067741 are implicated in this process. Besides, anti-cancer effects of gallic acid, icotinib hydrochloride, curcumin, ginsenoside Rg3, cryptotanshinone, nitidine chloride, cucurbitacin E, erlotinib, verteporfin, sophoridine, cisplatin and verteporfin in lung cancer are mediated through modulation of Hippo pathway. Here, we summarize the results of recent studies that investigated the role of Hippo signaling in the progression of lung cancer, the impact of non-coding RNAs on this pathway and the effects of anti-cancer agents on Hippo signaling in the context of lung cancer.

Deciphering Potential Role of Hippo Signaling Pathway in Breast Cancer: A Comprehensive Review

Breast cancer is a heterogeneous disease and a leading malignancy around the world. It is a vital cause of untimely mortality among women. Drug resistance is the major challenge for effective cancer therapeutics. In contrast, cancer stem cells (CSCs) are one of the reasons for drug resistance, tumor progression, and metastasis. The small population of CSCs present in each tumor has the ability of self-renewal, differentiation, and tumorigenicity. CSCs are often identified and enriched using a variety of cell surface markers (CD44, CD24, CD133, ABCG2, CD49f, LGR5, SSEA-3, CD70) that exert their functions by different regulatory networks, i.e., Notch, Wnt/β-catenin, hedgehog (Hh), and Hippo signaling pathways. Particularly the Hippo signaling pathway is the emerging and very less explored cancer stem cell pathway. Here, in this review, the Hippo signaling molecules are elaborated with respect to their ability of stemness as epigenetic modulators and how these molecules can be targeted for better cancer treatment and to overcome drug resistance.

Recent insights into the microRNA and long non-coding RNA-mediated regulation of stem cell populations

Stem cells are undifferentiated cells that have multi-lineage differentiation. The transition from self-renewal to differentiation requires rapid and extensive gene expression alterations. Since different stem cells exhibit diverse non-coding RNAs (ncRNAs) expression profiles, the critical roles of ncRNAs in stem cell reprogramming, pluripotency maintenance, and differentiation have been widely investigated over the past few years. Hence, in this current review, the two main categories of ncRNAs, microRNAs (miRNAs) and long non-coding RNAs (lncRNAs), are discussed. While the primary way by which miRNAs restrict mRNA transcription is through miRNA-mRNA interaction, lncRNAs have a wide range of effects on mRNA functioning, including interactions with miRNAs. Both of these ncRNAs participate in the post-transcriptional regulation of crucial biological mechanisms, such as cell cycle regulation, apoptosis, aging, and cell fate decisions. These findings shed light on a previously unknown aspect of gene regulation in stem cell fate determination and behavior. Overall, we summarized the key roles of miRNAs (including exosomal miRNAs) and lncRNAs in the regulation of stem cell populations, such as cardiac, hematopoietic, mesenchymal, neural, and spermatogonial, as well ncRNAs' influence on malignancy through modulating cancer stem cells, which might significantly contribute to clinical stem cell therapy and in regenerative medicine.

Tanshinone IIA reverses oxaliplatin resistance in colorectal cancer through microRNA-30b-5p/AVEN axis

This research aims to explore the role of Tanshinone IIA (Tan IIA) and microRNA (miR)-30b-5p in chemoresistance of colorectal cancer (CRC). The expression levels of miR-30b-5p and apoptosis and caspase activation inhibitor (AVEN) was detected by reverse transcription-quantitative polymerase chain reaction assay. The cell proliferation and apoptosis were examined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and flow cytometry assays. The target relationship between miR-30b-5p and AVEN was confirmed by Dual-luciferase reporter assay. Transwell assay was performed to assess CRC cells’ metastasis. Western blot was carried out to measure the apoptosis-related protein. The results showed that miR-30b-5p was lowly expressed in oxaliplatin-resistance CRC cells SW480 (SW480/R) compared to SW480 cells. Overexpression of miR-30b-5p significantly suppressed the malignant biological behaviors of SW480/R cells and significantly promoted the sensitivity of SW480/R cells to oxaliplatin by down-regulated AVEN expression. Besides, Tan IIA treatment upregulated miR-30b-5p expression in SW480/R cells. Moreover, miR-30b-5p upregulation strengthened the promoting effect of Tan IIA on the sensitivity of SW480/R cells to oxaliplatin. In conclusion, Tan IIA and miR-30b-5p could reverse oxaliplatin resistance of CRC cells and may thus be potential treatment strategies for treating patients with CRC.

Human bone marrow-mesenchymal stem cell-derived exosomal microRNA-188 reduces bronchial smooth muscle cell proliferation in asthma through suppressing the JARID2/Wnt/β-catenin axis

The functions of exosomes in allergic diseases including asthma have aroused increasing concerns. This paper focuses on the effects of exosomes derived from human bone marrow-mesenchymal stem cells (hBM-MSCs) on the proliferation of bronchial smooth muscle cells in asthma and the mechanism involved. Exosomes were extracted from hBM-MSCs and identified. Human BSMCs were induced with transforming growth factor (TGF)-β1 to mimic an asthma-like condition in vitro and then treated with exosomes. A mouse model with asthma was induced by ovalbumin (OVA) and treated with exosomes for in vivo study. The hBM-MSC-derived exosomes significantly reduced the abnormal proliferation and migration of TGF-β1-treated BSMCs. microRNA (miR)-188 was the most enriched miRNA in exosomes according the microarray analysis, and JARID2 was identified as a mRNA target of miR-188. Either downregulation of miR-188 or upregulation of JARID2 blocked the protective effects of exosomes on BSMCs. JARID2 activated the Wnt/β-catenin signaling pathway. In the asthmatic mice, hBM-MSC-derived exosomes reduced inflammatory cell infiltration, mucus production, and collagen deposition in mouse lung tissues. In conclusion, this study suggestes that hBM-MSC-derived exosomes suppress proliferation of BSMCs and lung injury in asthmatic mice through the miR-188/JARID2/Wnt/β-catenin axis. This study may provide novel insights into asthma management.

Inhibition of miR-185-3p Confers Erlotinib Resistance Through Upregulation of PFKL/MET in Lung Cancers

Erlotinib (ER), as an epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI), has a significant therapeutic effect in lung cancers. However, EGFR TKI resistance inevitably occurs after treatment for approximately 12 months, which weakens its antitumor effect. Here, we identified miR-185-3p as a significantly downregulated microRNA responsible for acquired EGFR TKI resistance in cells and patients with lung cancer. qRT-PCR and Western Blot were performed to determine the relative expression of miR-185-3p in ER-resistant tumor tissues and cells. The viability and apoptosis of lung cancer cells were evaluated by Cell Counting Kit-8 (CCK8) assay and flow cytometry, respectively. The binding between miR-185-3p and liver-type phosphofructokinase (PFKL) was verified by dual luciferase assay. It was found that overexpression of miR-185-3p conferred ER sensitivity in lung cancer cell lines. MiR-185-3p was downregulated in ER-resistant lung cancer cells (H1299/ER and A549/ER). MiR-185-3p inhibited proliferation and induced cell apoptosis in ER-resistant cells. Mechanistically, miR-185-3p downregulation contributed to ER resistance through upregulating the PFKL. Moreover, Mesenchymal to epithelial transition (MET) oncoprotein promoted EGFR-TKI resistance by regulating miR-185-3p and PFKL. These findings revealed a novel mechanism in which downregulation of miR-185-3p may induce overexpression of PFKL and MET and confer ER resistance in lung cells. Combination of PFKL/MET inhibitors and EGFR TKIs could be a rational therapeutic approach for lung cancer patients with EGFR mutation.

MicroRNA-188 inhibits biological activity of lung cancer stem cells through targeting MDK and mediating the Hippo pathway

New Findings

What is the central question of this study?

The aim was to investigate the function of microRNA‐188 in the biological characteristics of lung cancer stem cells and the molecular mechanisms involved.

What is the main finding and its importance?

This study highlights a new molecular mechanism involving microRNA‐188, MDK and the Hippo signalling pathway that plays a suppressive role in biological activity of lung cancer stem cells. This finding might offer new insights into gene‐based therapy for lung cancer.

Abstract

MicroRNAs (miRNAs) have been implicated in lung cancer and reported as new promising diagnostic and therapeutic tools for cancer control. Here, we investigated the action of microRNA‐188 (miR‐188) in lung cancer stem cells. We first tested miR‐188 expression in clinical samples of lung cancer patients, and a low expression profile of miR‐188 was found. Next, we analysed the role of miR‐188 in lung cancer stem cells with cell growth assays. To verify the in vitro results, we used a xenograft model to validate the capability of miR‐188 in tumorigenesis. Overexpression of miR‐188 reduced viability and metastasis of cancer stem cells. Similar results were reproduced in vivo, where overexpression of miR‐188 retarded tumour growth in mice. We also identified MDK as a target of miR‐188, and overexpression of MDK was found in lung cancer samples. Overexpressed MDK promoted the malignant behaviours of lung cancer stem cells. In addition, the Hippo pathway was found to be inactivated in lung cancer tissues, presenting as increased levels of YAP and TAZ. Suppression of the Hippo pathway also enhanced lung cancer stem cell activity and promoted the growth of xenograft tumours. To sum up, our results reveal that miR‐188 inhibits the malignant behaviours of lung cancer stem cells and the growth of xenograft tumours. This study might offer new insights into gene‐based therapies for cancer.