MicroRNAs that affect the Fanconi Anemia/BRCA pathway are downregulated in imatinib-resistant chronic myeloid leukemia patients without detectable BCR-ABL kinase domain mutations

Correlation analysis of bone marrow microvessel density and miRNA expression on drug resistance in patients with chronic myelogenous leukemia after tyrosine kinase inhibitor treatment

OBJECTIVE

This study analyzed the relationship between bone marrow microvessel density (MVD) and the expression of four miRNAs with chronic myelogenous leukemia (CML) resistance after tyrosine kinase inhibitor (TKI) treatment.

METHODS

234 CML patients were divided into resistance and non-resistance groups in terms of the results of the 5-year follow-up. Patients were divided into the Optimum response group and the Warning/Failure group based on TKI response. MVD was determined by immunohistochemistry, and the expression levels of four miRNAs (miR-106a, miR-155, miR-146a, and miR-340) in bone marrow biopsy specimens were examined by qPCR. We evaluated the association of MVD with four miRNAs and them predictive value for CML resistance after TKI treatment.

RESULTS

The MVD and the levels of miR-106a, miR-155, and miR-146a were significantly higher while the miR-340 level was lower in the resistance group than the non-resistance group. Besides, MVD had a significant correlation with the levels of miR-340 and miR-155. According to the results of survival analysis, MVD as well as miR-340 and miR-155 levels were observably correlated with 5-year survival of patients without TKI resistance. The results of the ROC curve indicated that the MVD, miR-106a, miR-340, and miR-155 had good predictive accuracy for CML resistance after TKI treatment. As for the results of multivariate analysis, disease stage, risk level (high risk), high MVD, low miR-340 expression, and high miR-155 expression were all independent risk factors for CML resistance.

CONCLUSION

MVD and the expression of miR-340 and miR-155 are closely associated with CML resistance after TKI treatment.

The role of mir-151a-5p in tumorigenesis; A systematic review

BACKGROUND

Highly supported microRNAs (miRNAs) are key players in cancer development. Each of these miRNAs may act as an oncomir, a tumor-suppressor, or both in various cancers. Mir-151a-5p is believed to be one of these miRNAs with diverse roles. We have conducted this systematic review to clarify the role of mir-151a-5p in formation of various cancers.

METHODS AND MATERIALS

We searched for existing articles in PubMed, Web of Science, Cochrane, Scopus, and RNAcentral databases up to November 2022. A total of 23 articles were qualified and included in the present systematic review. This review is registered on JBI at https://jbi.global/systematic-review-register. Expression levels, diagnostic and prognostic values, biological processes, and targeted downstream genes are included.

RESULTS

Assembled data indicate the expression levels of mir-151a-5p vary from down- to up-regulated based on the type of the cancer. Its functional role depends on the genetic profile of cancerous tissue. Results mostly point to the oncogenic role of this miRNA in Pituitary adenomas, Acute Myeloid Leukemia (AML), Endometrial, Lung, Barrett's carcinogenesis, Colorectal, Myelodysplastic syndromes, Hepatocellular carcinoma and Breast cancers, as its inhibited targets seem to be controlling several signaling pathways, cell adhesion, and cell cycle. At the same time, tumor-suppressing role has also been observed only in Malignant Pleural Mesothelioma, Central Nerve System (CNS) lymphoma, Chronic Myeloid and Acute Lymphocytic Leukemia. Two types of cancers, prostate and colon, show contradictory results as there are studies supporting both up- and down-regulation in these cancers. Pituitary adenomas, Barrett's carcinogenesis and CNS lymphomas are top cancers diagnosed with mir-151-5p. However, prognostic feature is only applicable to Lung adenocarcinoma.

DISCUSSION

Based on the present findings and further studies in the future, mir-151a-5p may be used as diagnostic and prognostic biomarkers or even a therapeutic target in cancer studies.

DATA AVAILABILITY STATEMENT

The articles used in this study can be found with the defined search phrase in mentioned databases. A list of selected articles will be available on reasonable requests.

MiRNA-146a-A Key Player in Immunity and Diseases

miRNA-146a, a single-stranded, non-coding RNA molecule, has emerged as a valuable diagnostic and prognostic biomarker for numerous pathological conditions. Its primary function lies in regulating inflammatory processes, haemopoiesis, allergic responses, and other key aspects of the innate immune system. Several studies have indicated that polymorphisms in miRNA-146a can influence the pathogenesis of various human diseases, including autoimmune disorders and cancer. One of the key mechanisms by which miRNA-146a exerts its effects is by controlling the expression of certain proteins involved in critical pathways. It can modulate the activity of interleukin-1 receptor-associated kinase, IRAK1, IRAK2 adaptor proteins, and tumour necrosis factor (TNF) targeting protein receptor 6, which is a regulator of the TNF signalling pathway. In addition, miRNA-146a affects gene expression through multiple signalling pathways, such as TNF, NF-κB and MEK-1/2, and JNK-1/2. Studies have been carried out to determine the effect of miRNA-146a on cancer pathogenesis, revealing its involvement in the synthesis of stem cells, which contributes to tumourigenesis. In this review, we focus on recent discoveries that highlight the significant role played by miRNA-146a in regulating various defence mechanisms and oncogenesis. The aim of this review article is to systematically examine miRNA-146a's impact on the control of signalling pathways involved in oncopathology, immune system development, and the corresponding response to therapy.

HucMSC exosomes promoted imatinib-induced apoptosis in K562-R cells via a miR-145a-5p/USP6/GLS1 axis

Chronic myeloid leukemia (CML) is a myeloproliferative neoplasm with increasing incidence worldwide. Growing evidence suggests that ubiquitin-specific proteases (USPs) play a role in cancer treatment. Dysregulation of miR-146a has been found in both adult and pediatric patients with acute leukemia. Knockdown of glutaminase-1 (GLS1) resulted in inhibition of tumor growth. However, the role of miR-146a-5p/USP6/GLS1 in leukemia and chemoresistance of leukemia cells remains to be elucidated. In the current study, USP6 level was increased in bone marrow aspiration specimens of patients with CML and associated with poor prognosis. USP6 was significantly upregulated in imatinib (IM)-resistant clinical samples compared with IM-sensitive samples. USP6 overexpression significantly inhibited IM-induced apoptosis of leukemia cells. Overexpressing USP6 significantly increased GLS1 ubiquitination to decrease GLS protein. A mechanism study indicated that USP6 regulation of IM resistance of CML cells was GLS1 dependent and regulated by miR-146a-5p. Administration of human umbilical cord mesenchymal stem cell (hucMSC) exosomes promoted IM-induced cell apoptosis through miR-145a-5p/USP6. Therefore, hucMSC exosomes promoted IM-induced apoptosis of K562-R cells by suppressing GLS1 ubiquitination to increase GLS protein via miR-146a-5p and its target GLS1. The findings highlight the importance of miR-146a-5p/USP6/GLS1 signaling in chemoresistance of leukemia and provide new insights into therapeutic strategies for chemoresistant leukemia.

CircRNAs: biogenesis, functions, and role in drug-resistant Tumours

Targeted treatment, which can specifically kill tumour cells without affecting normal cells, is a new approach for tumour therapy. However, tumour cells tend to acquire resistance to targeted drugs during treatment. Circular RNAs (circRNAs) are single-stranded RNA molecules with unique structures and important functions. With the development of RNA sequencing technology, circRNAs have been found to be widespread in tumour-resistant cells and to play important regulatory roles. In this review, we present the latest advances in circRNA research and summarize the various mechanisms underlying their regulation. Moreover, we review the role of circRNAs in the chemotherapeutic resistance of tumours and explore the clinical value of circRNA regulation in treating tumour resistance.

A miR-146a-5p/TRAF6/NF-kB p65 axis regulates pancreatic cancer chemoresistance: functional validation and clinical significance

Background: Dysregulated microRNA (miRNA) expression in cancer can act as a key factor that modifies biological processes, including chemoresistance. Our study aimed to identify the miRNAs associated with gemcitabine (GEM) resistance in pancreatic ductal adenocarcinoma (PDAC) and to explore the potential mechanisms.

Methods: The miRNA microarray was used to identify miRNAs associated with GEM resistance. Quantitative real-time PCR was used to examine miR-146a-5p expression in paired PDAC and adjacent normal tissues. Bioinformatics analysis, luciferase reporter assays, and chromatin immunoprecipitation assays were used to confirm tumor necrosis factor receptor-associated factor 6 (TRAF6) as a direct target of miR-146a-5p and to explore the potential transcription factor binding and regulation by miR-146a-5p. In vitro and in vivo experiments were performed to investigate the mechanisms.

Results: MiR-146a-5p expression was significantly decreased in PDAC tissues compared with adjacent normal tissues, and miR-146a-5p expression correlated with prognosis in PDAC patients. Functional studies indicated that miR-146a-5p suppressed PDAC cell proliferation and sensitized PDAC cells to GEM chemotherapy by targeting the 3'-untranslated region (3′-UTR) of TRAF6. MiR-146a-5p was also observed to downregulate the TRAF6/NF-κB p65/P-gp axis, which regulates PDAC cell growth and chemoresistance.

Conclusions: Taken together, the results indicate that the miR-146a-5p/TRAF6/NF-κB p65 axis drives pancreatic chemoresistance by regulating P-gp, suggesting that miR-146a-5p may be utilized as a new therapeutic target and prognostic marker in PDAC patients.

MicroRNAs and response to therapy in leukemia

A variety of epigenetic factors involved in leukemia pathogenesis. Among various epigenetic factors, microRNAs (miRNAs) have emerged as important players, which affect a sequence of cellular and molecular signaling pathways. Leukemia is known as progressive cancer, which is related to many health problems in the world. It has been shown that the destruction of the blood-forming organs could lead to abnormal effects on the proliferation and development of leukocytes and their precursors. Despite many attempts for approved effective and powerful therapies for patients with leukemia, finding and developing new therapeutic approaches are required. One of the important aspects of leukemia therapy, identification of underlying cellular and molecular mechanisms involved in the pathogenesis of leukemia. Several miRNAs (ie, miR-103, miR-101, mit-7, let-7i, miR-424, miR-27a, and miR-29c) and play major roles in response to therapy in patients with leukemia. miRNAs exert their effects by targeting a variety of targets, which are associated with response to therapy in patients with leukemia. It seems that more understanding about the roles of miRNAs in response to therapy in patients with leukemia could contribute to better treatment of patients with leukemia. Here, for the first time, we summarized various miRNAs, which are involved in response to therapy in the treatment patients with leukemia.

miR-146a-5p: Expression, regulation, and functions in cancer

Cancer as we know it is actually an umbrella term for over 100 very unique malignancies in various tissues throughout the human body. Each type, and even subtype of cancer, has different genetic, epigenetic, and other cellular events responsible for malignant development and metastasis. Recent work has indicated that microRNAs (miRNAs) play a major role in these processes, sometimes by promoting cancer growth and other times by suppressing tumorigenesis. miRNAs are small, noncoding RNAs that negatively regulate expression of specific target genes. This review goes into an in-depth look at the most recent finding regarding the significance of one particular miRNA, miR-146a-5p, and its involvement in cancer. Target gene validation and pathway analysis have provided mechanistic insight into this miRNA's purpose in assorted tissues. Additionally, this review outlines novel findings that suggest miR-146a-5p may be useful as a noninvasive biomarker and as a targeted therapeutic in several cancers. This article is categorized under: RNA in Disease and Development > RNA in Disease Regulatory RNAs/RNAi/Riboswitches > Regulatory RNAs.

miR‑146a‑5p targets TCSF and influences cell growth and apoptosis to repress NSCLC progression

Several studies have indicated that microRNAs (miRs) mediate multiple pathways associated with tumorigenesis and progression. Our preliminary study experimentally verified that miR-146a-5p has a role in the biological behavior of non-small cell lung cancer (NSCLC) cells. To perform further investigation of miR-146a-5p, the present study evaluated miR-146a-5p by targeting its downstream gene tumor collagenase stimulatory factor (TCSF) to influence cell viability, proliferation and apoptosis in NSCLC. Online sequence prediction, a thorough search of the open source database The Cancer Genome Atlas (TCGA), immunohistochemistry (IHC) of TCSF in clinical lung cancer tissues, and a dual-luciferase assay, as well as assays to test viability, proliferation and apoptosis in vitro, were conducted to explain the targeted regulation association between miR-146a-5p and TCSF in NSCLC. The miRanda and TargetScanHuman database revealed that TCSF and miR-146a-5p had target binding sites. A luciferase reporter assay demonstrated that miR-146a-5p and TCSF did have complementary sequences (P<0.05). From the TCGA database, TCSF was highly expressed in lung adenocarcinoma and lung squamous cell carcinoma tissues when compared with normal lung tissues (P<0.05). Furthermore, the protein level of TCSF in cancerous lung tissues was determined by IHC, and it was concluded that TCSF protein was also upregulated in NSCLC tissues (P<0.001). A significant difference was identified following in vitro experiments for the NSCLC cell line A549, which revealed that miR-146a-5p and TCSF regulated cell viability, proliferation and apoptosis. In conclusion, the present study verified the target action association between TCSF and miR-146a-5p with high throughput data analysis and experimental results in NSCLC.

Towards Comprehension of the ABCB1/P-Glycoprotein Role in Chronic Myeloid Leukemia

Abstract: The introduction of imatinib (IM), a BCR-ABL1 tyrosine kinase inhibitor (TKI), has represented a significant advance in the first-line treatment of chronic myeloid leukemia (CML). However, approximately 30% of patients need to discontinue IM due to resistance or intolerance to this drug. Both resistance and intolerance have also been observed in treatment with the second-generation TKIs-dasatinib, nilotinib, and bosutinib-and the third-generation TKI-ponatinib. The mechanisms of resistance to TKIs may be BCR-ABL1-dependent and/or BCR-ABL1-independent. Although the role of efflux pump P-glycoprotein (Pgp), codified by the ABCB1 gene, is unquestionable in drug resistance of many neoplasms, a longstanding question exists about whether Pgp has a firm implication in TKI resistance in the clinical scenario. The goal of this review is to offer an overview of ABCB1/Pgp expression/activity/polymorphisms in CML. Understanding how interactions, associations, or cooperation between Pgp and other molecules-such as inhibitor apoptosis proteins, microRNAs, or microvesicles-impact IM resistance risk may be critical in evaluating the response to TKIs in CML patients. In addition, new non-TKI compounds may be necessary in order to overcome the resistance mediated by Pgp in CML.