Tumor Suppressor miRNAs Research Articles

Impact of UV-Irradiated Mesoporous Titania Nanoparticles (mTiNPs) on Key Onco- and Tumor Suppressor microRNAs of PC3 Prostate Cancer Cells

Background: Mesoporous titanium dioxide nanoparticles (mTiNPs) are known for their chemical stability, non-toxicity, antimicrobial and anticancer effects, as well as for their photocatalytic properties. When this material is subjected to UV radiation, its electronic structure shifts, and during that process, reactive oxygen species are generated, which in turn exert apoptotic events on the cancer cells. Objectives: We evaluated the cytotoxic effects of UV-irradiated mTiNPs on prostate cancer (PCa) cell line PC3 with the aim of demonstrating that the interaction between UV-light and mTiNPs positively impacts the nanomaterial’s cytotoxic efficiency. Moreover, we assessed the differential expression of key oncomiRs and tumor suppressor (TS) miRNAs, as well as their associated target genes, in cells undergoing this treatment. Methods: PBS-suspended mTiNPs exposed to 290 nm UV light were added at different concentrations to PC3 cells. Cell viability was determined after 24 h with a crystal violet assay. Then, the obtained IC50 concentration of UV-nanomaterial was applied to a new PC3 cell culture, and the expression of a set of miRNAs and selected target genes was evaluated via qRT-PCR. Results: The cells exposed to photo-activated mTiNPs required 4.38 times less concentration of the nanomaterial than the group exposed to non-irradiated mTiNPs to achieve the half-maximal inhibition, demonstrating an improved cytotoxic performance of the UV-irradiated mTiNPs. Moreover, the expression of miR-18a-5p, miR-21-5p, and miR-221-5p was downregulated after the application of UV-mTiNPs, while TS miR-200a-5p and miR-200b-5p displayed an upregulated expression. Among the miRNA target genes, PTEN was found to be upregulated after the treatment, while BCL-2 and TP53 were underexpressed. Conclusions: Our cytotoxic outcomes coincided with previous reports performed in other cancer cell lines, strongly suggesting UV-irradiated mTiNPs as a promising nano-therapeutic approach against PCa. On the other hand, to the best of our knowledge, this is the first report exploring the impact of UV-irradiated mTiNPs on key onco- and TS microRNAs in PCa cells.

Selective arm-usage of pre-miR-1307 dysregulates angiogenesis and affects breast cancer aggressiveness

BackgroundBreast cancer is the leading cause of cancer-related mortality in women. Deregulation of miRNAs is frequently observed in breast cancer and affects tumor biology. A pre-miRNA, such as pre-miR-1307, gives rise to several mature miRNA molecules with distinct functions. However, the impact of global deregulation of pre-miR-1307 and its individual mature miRNAs in breast cancer has not been investigated in breast cancer, yet.ResultsHere, we found significant upregulation of three mature miRNA species derived from pre-miR-1307 in human breast cancer tissue. Surprisingly, the overexpression of pre-miR-1307 in breast cancer cell lines resulted in reduced xenograft growth and impaired angiogenesis. Mechanistically, overexpression of miR-1307-5p altered the secretome of breast cancer cells and reduced endothelial cell sprouting. Consistently, expression of miR-1307-5p was inversely correlated with endothelial cell fractions in human breast tumors pointing at an anti-angiogenic role of miR-1307-5p. Importantly, the arm usage of miR-1307 and other miRNAs was highly correlated, which suggests an undefined common regulatory mechanism.ConclusionsIn summary, miR-1307-5p reduces angiogenesis in breast cancer, thereby antagonizing the oncogenic effects of miR-1307-3p. Our results emphasize the importance of future research on the regulation of miRNA arm selection in cancer. The underlying mechanisms might inspire new therapeutic strategies aimed at shifting the balance towards tumor-suppressive miRNA species.Graphical

Unraveling the mechanism of microRNA-134 in colon cancer progression: Targeting KRAS and PIK3CA for cell cycle control and histone deacetylase regulation.

Colon cancer is the leading cause of cancer-related deaths worldwide. MicroRNAs (miRNAs) are key regulators of gene expression, often dysregulated in colon cancer. This study aims to elucidate the therapeutic role of miR-134-5p as a tumor suppressor miRNA in colon cancer cells. We analyzed miRNA expression profiles in primary and metastatic colon cancer cells. The clinical significance of miR-134-5p was evaluated using the TCGA database. Bioinformatics tools (HADDOCK) predicted miRNA-mRNA interactions and the molecular docking of miRNA-mRNA-AGO2 complexes. Luciferase reporter assays, cell proliferation, immunofluorescence, colony forming unit assays, and qRT-PCR analysis assessed miR-134-5p effects on KRAS, PIK3CA, and downstream signaling pathways in primary and metastatic colon cancer cells. miR-134-5p was downregulated in colon cancer cells. Bioinformatics analysis suggested KRAS, PIK3CA, EGFR, and HDAC5 as potential targets. HADDOCK analysis revealed strong binding affinity and structural stability between KRAS, PIK3CA, miR-134-5p, and AGO2. Gene-reporter assays confirmed miR-134-5p-mediated degradation of KRAS and PIK3CA. miR-134-5p transfection reduced KRAS and PI3K protein levels, suppressed EGFR/RTK signaling and its downstream targets, and inhibited HDAC expression, ultimately reducing colon cancer cell proliferation. The results of this study confirm that miR-134-5p acts as a potential tumor suppressor miRNA in colon cancer cells by inhibiting KRAS and PI3K expression through AGO2-mediated gene silencing. It deregulates downstream EGFR signaling and HDACs, thereby reducing colon cancer cell proliferation. These findings highlight miR-134-5p as a promising therapeutic target for miRNA-mediated anticancer therapy.

The miRNA-mRNA Regulatory Network in Human Hepatocellular Carcinoma by Transcriptomic Analysis From GEO.

Bioinformatics analysis of hepatocellular carcinoma (HCC) expression profiles can aid in understanding its molecular mechanisms and identifying new targets for diagnosis and treatment. In this study, we analyzed expression profile datasets and miRNA expression profiles related to HCC from the GEO using R software to detect differentially expressed genes (DEGs) and differentially expressed miRNAs (DEmiRs). Common DEGs were identified, and a PPI network was constructed using the STRING database and Cytoscape software to identify hub genes. The reduced levels of tumor suppressor miRNAs or down regulated DEmiRs may be increased levels of oncogenes, the oncomirs or up regulated DEmiRs may be decreased levels of tumor suppressor genes in cancerous cells. According to this strategy, increased and decreased DEGs, also increased and decreased DEmiRs were selected. The multimir package was employed to predict target genes for DEmiRs then DEmiRs-hub gene network created. We identified approximately 1000 overlapping DEGs and 60 DEmiRs. Hub genes included RRM2, MELK, KIF11, KIF23, NCAPG, DLGAP5, BUB1B, AURKB, CCNB1, KIF20A, CCNA2, TTK, PBK, TOP2A, CDK1, MAD2L1, BIRC5, ASPM, CDCA8, and CENPF, all associated with significantly worse survival in HCC. miR-224, miR-24, miR-182, miRNA-1-3p, miR-30a, miR-27a, and miR-214 were identified as important DEmiRs with targeting more than six hub genes. Generally, our findings offer insight into the interaction of hub genes and miRNAs in the development of HCC by bioinformatics analysis, information that may prove useful in identifying biomarkers and therapeutic targets in HCC.

Exosomes and microRNAs: Powerful mediators of cancer and their clinical applications

Exosomes are nanoscale extracellular vesicles secreted by nearly all cell types, playing a crucial role in intercellular communication. These vesicles transport biomolecules, including proteins, lipids, and nucleic acids, particularly microRNAs (miRNAs), which regulate post-transcriptional gene expression. In cancer, exosomes influence critical processes such as cell proliferation, angiogenesis, metastasis, and therapeutic resistance by transferring oncogenic or tumor-suppressor miRNAs to recipient cells. Their stability in biological fluids and their ability to protect molecular cargo make them promising candidates for non-invasive diagnostics and targeted therapeutics. This review explores the mechanisms of exosome biogenesis, their molecular composition, and their roles in cancer progression, alongside emerging clinical applications and challenges.

Analysis of Methylation of Tumor-suppressive miRNAs and KRAS/TP53 Mutations in Pancreatic Juice.

We previously reported the usefulness of detecting aberrant methylation in tumor suppressive microRNAs (miRNAs) in bile and plasma to discriminate pancreaticobiliary cancers from benign pancreaticobiliary diseases. This study analyzed the methylation of miRNAs in pancreatic juice to identify those specific to pancreatic cancer (PC). Pancreatic juice was collected from 20 patients with PC, including eight with intraductal papillary mucinous carcinoma (IPMC), two with low grade-pancreatic intraepithelial neoplasia (LG-PanIN), 32 with LG-intraductal papillary mucinous neoplasm (IPMN), and seven with benign pancreatic lesions. Polymerase chain reaction amplification and sequencing were performed for three tumor suppressive miRNAs (miR-200a, 200b, and 1247), and their methylation rates were determined. Additionally, KRAS and TP53 mutations were analyzed. The methylation rate of miR-1247 was significantly higher in patients with PC than in those with LG-PanIN/IPMN. Furthermore, it was significantly higher in patients with IPMC than in those with LG-IPMN. KRAS and TP53 mutations were detected in seven (70%) and one (10%) of the patients with PC, respectively. Analyzing the methylation of miR-1247 in addition to KRAS and TP53 mutations in pancreatic juice may be useful to distinguish PC from PanIN/IPMN.

Identification of Tumor-Suppressive miR-30a-3p Controlled Genes: ANLN as a Therapeutic Target in Breast Cancer.

Our recently created RNA-sequence-based microRNA (miRNA) expression signature in breast cancer clinical specimens revealed that some miR-30 family members were significantly downregulated in cancer tissues. Based on TCGA database analyses, we observed that among the miR-30 family members, miR-30a-3p (the passenger strand derived from pre-miR-30a) was significantly downregulated in breast cancer (BC) clinical specimens, and its low expression predicted worse prognoses. Ectopic expression assays showed that miR-30a-3p transfected cancer cells (MDA-MB-157 and MDA-MB-231) had their aggressive phenotypes significantly suppressed, e.g., their proliferation, migration, and invasion abilities. These data indicated that miR-30a-3p acted as a tumor-suppressive miRNA in BC cells. Our subsequent search for miR-30a-3p controlled molecular networks in BC cells yielded a total of 189 genes. Notably, among those 189 genes, cell-cycle-related genes (ANLN, MKI67, CCNB1, NCAPG, ZWINT, E2F7, PDS5A, RIF1, BIRC5, MAD2L1, CACUL1, KIF23, UBE2S, EML4, SEPT10, CLTC, and PCNP) were enriched according to a GeneCodis 4 database analysis. Moreover, the overexpression of four genes (ANLN, CCNB1, BIRC5, and KIF23) significantly predicted worse prognoses for patients with BC according to TCGA analyses. Finally, our assays demonstrated that the overexpression of ANLN had cancer-promoting functions in BC cells. The involvement of miR-30a-3p (the passenger strand) in BC molecular pathogenesis is a new concept in cancer research, and the outcomes of our study strongly indicate the importance of analyzing passenger strands of miRNAs in BC cells.

Direct and indirect modulation of STAT3/CSE/H2S axis in triple negative breast cancer by non-coding RNAs: MALAT-1 lncRNA, miR-486–5p and miR-30a-5p

Recently, our research group reported an upregulated expression profile of cystathionine γ-lyase (CSE) and cystathionine β-synthase (CBS), key enzymes involved in hydrogen sulfide (H2S) production, in triple-negative breast cancer (TNBC) patients. However, the regulatory mechanisms underlying such altered expression patterns are not yet fully understood. In this study, we focused on the role of the STAT3/CSE/H2S axis and the potential involvement of non-coding RNAs (ncRNAs), including long and short ncRNAs, in modulating this pivotal pathway. The results revealed that STAT3 was upregulated and positively correlated with CSE expression in BC patients. Additionally, the lncRNA MALAT-1 was found to regulate STAT3 expression, indirectly influencing CSE levels. Furthermore, we explored the interplay between the IGF-1R as a gatekeeper for JAK/STAT pathway and accordingly its impact on the STAT3/CSE/H2S axis in TNBC cell lines. Our results demonstrated that miR-486–5p, a tumor suppressor miRNA, directly targets IGF-1R, leading to the downstream suppression of STAT3 and CSE in MDA-MB-231 cells. To identify a direct upstream repressor of CSE and CBS, we conducted an in silico analysis and identified miR-30a-5p as a promising candidate. When ectopically expressed, miR-30a-5p was downregulated in BC tissues and effectively suppressed CSE and CBS expression. In conclusion, this study revealed novel regulatory mechanisms involved in CSE and CBS expression in TNBC patients and cell lines. Abolishing H2S-synthesizing machinery, particularly via miR-30a-5p, may represent a promising therapeutic strategy for TNBC patients.

Tumor Suppressor miR-27a-5p and Its Significance for Breast Cancer.

Background: MicroRNAs are well established as master regulators of carcinogenesis and potential biomarkers in breast cancer (BC). In a preliminary effort, we found miR-27a-5p to be significantly downregulated in experimentally derived mammospheres and BC patients from The Cancer Genome Atlas Breast Invasive Carcinoma (TCGA-BRCA) dataset. Objectives. Herein, we sought to investigate the putative involvement of miR-27a-5p in promoting a migratory phenotype of breast cancer cells, and establish whether miR-27a-5p is associated with patient clinicopathological characteristics. Methods: miR-27a-5p capability of inducing a metastasis-prone cell phenotype was analyzed in SUM159 and MDA-MB-231, both representing the triple negative BC subtype. miR-27a-5p expression profile was carried out in a cohort of 232 BC patients and normal breast tissues (NBTs) by RT-qPCR. Results: Transient miR-27a-5p inhibition did not affect cell proliferation but led to a significant increase of cell migration in knocked-down compared to control cells. Following quantification in the patient cohort, miR-27a-5p was found higher in NBTs (Median 2.28, IQR 1.50-5.40) and pre-invasive breast lesions (Median 3.32, IQR 1.68-4.32) compared to tumors. In particular, miR-27a-5p was less expressed in patients with synchronous (Median 1.03, IQR 0.83-1.58) or metachronous (Median 1.83, IQR 1.29-3.17) metastases than in patients free from metastases after a 5-year follow-up (Median 2.17, IQR 1.19-3.64), suggesting that miR-27a-5p expression is negatively correlated with breast pathology evolution (R = -0.13, p = 0.038). However, time-to-event analysis did not highlight significant associations with patient outcome in either our internal cohort or TCGA-BRCA dataset. Conclusions: Our study suggests a potential role of miR-27a-5p as tumor suppressor miRNA in breast cancer. Further investigations may help define its biomarker potential in each breast cancer subtype, and identify other molecular partners as targets for new interventions.

EXTH-52. SIMULTANEOUS TARGETING OF TUMOR CELLS AND TUMOR-ASSOCIATED MACROPHAGES TO REPROGRAM GLIOBLASTOMA BY TUMOR-SUPPRESSIVE MICRORNA

Abstract Glioblastoma (GBM) is the most aggressive type of primary brain tumors due in part to cell-intrinsic and cell-extrinsic mechanisms. The ability of GBM tumor to not only resist conventional therapies but also induce an immunosuppressive tumor microenvironment (TME) is thought to underlie the failure of immunotherapies. Thus, strategies to target both tumor cells and immunosuppressive immune cells, such as tumor-associated macrophages (TAMs), are of great interest. The ability of microRNA (miRNA) to target multiple genes is favorable to alter the character of the TME and cancer cells. Previously, we have shown that tumor suppressive miRNA, miR-138, can effectively regulate the genes in GBM cells relating to cell proliferation and viability. The exogenous delivery of miRNAs, however, has been limited due to the lack of delivery mechanisms that minimize off target effects. We argue that extracellular vesicles (EVs) are an ideal modality of targeted delivery for therapeutic miRNA, which we can accomplish by decorating the EV surface with cancer specific ligands, such as folate. Here, we report that trypsin digestion of the EV surface can increase the surface labeling efficiency for cancer targeting ligands. Folate-labeled trypsinized EVs effectively targeted folate receptor (FR) positive GBM cells and TAMs, delivering miR-138 in in vitro and in vivo orthotopic intracranial murine models of GBM. This simultaneous delivery decreased cancer cell proliferation and altered macrophage polarization through the inhibition of known target genes, phenotypically reprogramming both cancer cells and TAMs. To our knowledge, this is the first preclinical study attempting to target both tumor cells and innate immunity by delivering tumor suppressive miR-138 using a trypsinized EV-based RNA delivery system. These findings can be rapidly translated into a novel therapeutic option for GBM patients.

MGAT4A/Galectin9-Driven N-Glycosylation Aberration as a Promoting Mechanism for Poor Prognosis of Endometrial Cancer with TP53 Mutation.

Emerging evidence recognizes aberrant glycosylation as the malignant characteristics of cancer cells, but little is known about glycogenes' roles in endometrial carcinoma (EC), especially the most aggressive subtype carrying TP53 mutations. Using unsupervised hierarchical clustering, an 11-glycogene cluster is identified to distinguish an EC subtype associated with frequent TP53 mutation and worse prognosis. Among them, MGAT4A (alpha-1,3-mannosyl-glycoprotein 4-β-N-acetylglucosaminyltransferase A) emerges as the most consistently overexpressed glycogene, contributing to EC aggressiveness. In the presence of galectin-9, MGAT4A increases EC cell proliferation and invasion via promoting glucose metabolism. N-glycoproteomics further revealed GLUT1, a glucose transporter, as a glycoprotein modified by MGAT4A. Binding of galectin-9 to the MGAT4A-branched N-glycan on GLUT1 enhances its cell membrane distribution, leading to glucose uptake increase. In addition, oncogenic mutations of TP53 gene in EC cells upregulate MGAT4A expression by disrupting the regulatory oversight exerted by wild-type p53 on tumor-suppressive miRNAs, including miR-34a and miR-449a/b. The findings highlight a new molecular mechanism involving MGAT4A-regulated N-glycosylation on the key regulator of glucose metabolism in p53 mutants-driven EC aggressiveness, which may provide a strategic avenue to combat advanced EC.

Replenishing co-downregulated miR-100-5p and miR-125b-5p in malignant germ cell tumors causes growthinhibition through cell cycle disruption.

MicroRNAs (miRNAs) are short, nonprotein-coding RNAs, and their expression is dysregulated in malignant germ cell tumors (GCTs). Here, we investigated the causes and consequences of downregulated miR-99a-5p/miR-100-5p (functionally identical) and miR-125b-5p levels in malignant GCTs regardless of age, site, or subtype. Quantitative RT-PCR was used to assess miR-99a-5p/miR-100-5p, miR-125b-5p, and associated gene expression in malignant GCT tissues/cell lines [seminoma (Sem), yolk sac tumor (YST), embryonal carcinoma (EC)]. Cells were treated with demethylating 5-azacytidine and pyrosequencing was performed. Combination miR-100-5p/miR-125b-5p mimic replenishment was used to treat malignant GCTcells. Global messenger RNA (mRNA) targets of the replenished miRNAs were identified and Metascape used to study pathway effects. We found that expression levels of miR-99a-5p/miR-100-5p and miR-125b-5p, their respective pri-miRNAs, and associated genes from chromosomes 11 and 21 (chr11/chr21) were downregulated and highly correlated in malignant GCTcells. Treatment with 5-azacytidine caused upregulation of these miRNAs, with pyrosequencing revealing hypermethylation of their chr11/chr21 loci, likely contributing to miR-100-5p/miR-125b-5p downregulation. Combination miR-100-5p/miR-125b-5p mimic replenishment resulted in growth inhibition in Sem/YST cells, with miR-100-5p/miR-125b-5p mRNA targets enriched in downregulated genes, which were involved in cell cycle (confirmed by flow cytometry) and signaling pathways. Knockdown of the miR-100-5p/miR-125b-5p target tripartite motif containing 71 (TRIM71kd) recapitulated miR-100-5p/miR-125b-5p replenishment, with growth inhibition and cell cycle disruption of Sem/YST/EC cells. Further, replenishment led to reduced lin-28 homolog A (LIN28A) levels and concomitant increases in let-7 (MIRLET7B) tumor suppressor miRNAs, creating a sustained reversion of cell phenotype. In summary, combination miR-100-5p/miR-125b-5p mimic replenishment or TRIM71kd caused growth inhibition in malignant GCTcells via cell cycle disruption. Further studies are now warranted, including mimic treatment alongside conventional platinum-based chemotherapy.

Progress in Precision Medicine for Head and Neck Cancer.

This paper presents a comprehensive comparative analysis of biomarkers for head and neck cancer (HNC), a prevalent but molecularly diverse malignancy. We detail the roles of key proteins and genes in tumourigenesis and progression, emphasizing their diagnostic, prognostic, and therapeutic relevance. Our bioinformatic validation reveals crucial genes such as AURKA, HMGA2, MMP1, PLAU, and SERPINE1, along with microRNAs (miRNA), linked to HNC progression. OncomiRs, including hsa-miR-21-5p, hsa-miR-31-5p, hsa-miR-221-3p, hsa-miR-222-3p, hsa-miR-196a-5p, and hsa-miR-200c-3p, drive tumourigenesis, while tumour-suppressive miRNAs like hsa-miR-375 and hsa-miR-145-5p inhibit it. Notably, hsa-miR-155-3p correlates with survival outcomes in addition to the genes RAI14, S1PR5, OSBPL10, and METTL6, highlighting its prognostic potential. Future directions should focus on leveraging precision medicine, novel therapeutics, and AI integration to advance personalized treatment strategies to optimize patient outcomes in HNC care.

MiRNA Profiling of Areca Nut-Induced Carcinogenesis in Head and Neck Cancer.

While miRNAs are increasingly recognized for their role in tumorigenesis, their involvement in head and neck cancer (HNC) remains insufficiently explored. Additionally, the carcinogenic mechanisms of areca nut, a major habitual carcinogen in Southeast Asia, are not well understood. This study adopts a systematic approach to identify miRNA profiles associated with areca nut-induced HNC. Using miRNA microarray analysis, we identified 292 miRNAs dysregulated in areca nut-treated HNC cells, with 136 upregulated and 156 downregulated. Bioinformatic analysis of the TCGA-HNSC dataset uncovered a set of 692 miRNAs relevant to HNC development, comprising 449 overexpressed and 243 underexpressed in tumor tissues. Integrating these datasets, we defined a signature of 84 miRNAs, including 39 oncogenic miRNAs (OncomiRs) and 45 tumor-suppressive miRNAs (TsmiRs), highlighting their pivotal role in areca nut-induced carcinogenesis. MultiMiR analysis identified 740 genes cross-regulated by eight hub TsmiRs, significantly impacting key cancer-related pathways (p53, PI3K-AKT, MAPK, and Ras) and critical oncogenic processes. Moreover, we validated miR-499a-5p as a vital regulator, demonstrating its ability to mitigate areca nut-induced cancer progression by reducing cell migration, invasion, and chemoresistance. Thus, this miRNA signature addresses a crucial gap in understanding the molecular underpinnings of areca nut-induced carcinogenesis and offers a promising platform for clinical applications in risk assessment, diagnosis, and prognosis of areca nut-associated malignancies.

The Association of Neuroendocrine Differentiation with MicroRNA 21 and MicroRNA let7f Expression and the Clinicopathological Parameters in Primary Invasive Breast Carcinomas with Neuroendocrine Features.

MiRNAs have been reported as biomarkers with diagnostic, prognostic, and predictive value for many different diseases. Therapeutic agents targeting some miRNAs are currently being developed. We aimed to compare BC-NEFs (carcinoma of the breast with neuroendocrine features) with IDC (invasive ductal carcinoma) cases without neuroendocrine features in terms of the level of miRNA expression known to show the oncogenic (miR-21) and tumor-suppressor effects (miR-let7f) and the clinicopathological features. A total of 29 patients with a diagnosis of BC-NEFs (15 cases with neuroendocrine differentiation >50% of the whole section of tumor and 14 cases with neuroendocrine differentiation 10-50% of the tumor) and 30 patients with a diagnosis of IDC (no neuroendocrine differentiation) were retrospectively re-evaluated. Expression levels of miR-21 and miR-let7f were determined by the qRT-PCR method in paraffin tissue blocks. MiR-21 expression was significantly higher in the IDC group than in the group with BC-NEFs. miR-let7f expression was significantly lower in the group with BC-NEFs compared to the IDC group. A high expression level of miR-21 was found to be associated with progesterone receptor (PR) negativity. Our findings show that the presence of NEFs in breast carcinomas makes a significant difference in the expression levels of the investigated oncogenic (miR-21) and tumor-suppressor (miR-let7f) miRNAs. These findings suggest that miRNAs may be a potential biomarker in BC-NEFs and would benefit from targeted therapy.

Cancer Pathways Targeted by Berberine: Role of microRNAs.

Cancer is a complex and heterogeneous malignant disease. Due to its multifactorial nature, including progressive changes in genetic, epigenetic, transcript, and protein levels, conventional therapeutics fail to save cancer patients. Evidence indicates that dysregulation of microRNA (miRNA) expression plays a crucial role in tumorigenesis, metastasis, cell proliferation, differentiation, metabolism, and signaling pathways. Moreover, miRNAs can be used as diagnostic and prognostic markers and therapeutic targets in cancer. Berberine, a naturally occurring plant alkaloid, has a wide spectrum of biological activities in different types of cancers. Inhibition of cell proliferation, metastasis, migration, invasion, and angiogenesis, as well as induction of cell cycle arrest and apoptosis in cancer cells, is reported by berberine. Recent studies suggested that berberine regulates many oncogenic and tumor suppressor miRNAs implicated in different phases of cancer. This review discussed how berberine inhibits cancer growth and propagation and regulates miRNAs in cancer cells. And how berberine-mediated miRNA regulation changes the landscape of transcripts and proteins that promote or suppress cancer progression. Overall, the underlying molecular pathways altered by berberine and miRNA influencing the tumor pathophysiology will enhance our understanding to combat the malignancy.

Development of miRNA-based PROTACs targeting Lin28 for breast cancer therapy.

Lin28, a highly conserved carcinogenic protein, plays an important role in the generation of cancer stem cells, contributing to the unfavorable prognosis of cancer patients. This RNA binding protein specifically binds to pri/pre-microRNA (miRNA) lethal-7 (let-7), impeding its miRNA maturation. The reduced expression of tumor suppressor miRNA let-7 fosters development and progression-related traits such as proliferation, invasion, metastasis, and drug resistance. We report a series of miRNA-based Lin28A-miRNA proteolysis-targeting chimeras (Lin28A-miRNA-PROTACs) designed to efficiently degrade Lin28A through a ubiquitin-proteasome-dependent mechanism, resulting in up-regulation of mature let-7 family. The augmented levels of matured let-7 miRNAs further exert inhibitory effects on cancer cell proliferation and migration, and increase its sensitivity to chemotherapy. In a mouse ectopic tumor model, Lin28A-miRNA-PROTAC demonstrates a substantial efficacy in inhibiting tumor growth. When combined with tamoxifen, the tumors exhibit gradual regression. This study displays an effective miRNA-based PROTACs to degrade Lin28A and inhibit tumor growth, providing a promising therapeutic avenue for cancer treatment with miRNA-based therapy.

Understanding the role of miRNAs in cervical cancer pathogenesis and therapeutic responses.

Cervical cancer (CC) is the most common cancer in women and poses a serious threat to health. Despite familiarity with the factors affecting its etiology, initiation, progression, treatment strategies, and even resistance to therapy, it is considered a significant problem for women. However, several factors have greatly affected the previous aspects of CC progression and treatment in recent decades. miRNAs are short non-coding RNA sequences that regulate gene expression by inhibiting translation of the target mRNA. miRNAs play a crucial role in CC pathogenesis by promoting cancer stem cell (CSC) proliferation, postponing apoptosis, continuing the cell cycle, and promoting invasion, angiogenesis, and metastasis. Similarly, miRNAs influence important CC-related molecular pathways, such as the PI3K/AKT/mTOR signaling pathway, Wnt/β-catenin system, JAK/STAT signaling pathway, and MAPK signaling pathway. Moreover, miRNAs affect the response of CC patients to chemotherapy and radiotherapy. Consequently, this review aims to provide an acquainted summary of onco miRNAs and tumor suppressor (TS) miRNAs and their potential role in CC pathogenesis and therapy responses by focusing on the molecular pathways that drive them.

Mir-744-5p inhibits cell growth and angiogenesis in osteosarcoma by targeting NFIX

BackgroundOsteosarcoma (OS) is a malignant bone tumor that commonly occurs in children and adolescents under the age of 20. Dysregulation of microRNAs (miRNAs) is an important factor in the occurrence and progression of OS. MicroRNA miR-744-5p is aberrantly expressed in various tumors. However, its roles and molecular targets in OS remain unclear.MethodsDifferentially expressed miRNAs in OS were analyzed using the Gene Expression Omnibus dataset GSE65071, and the potential hub miRNA was identified through weighted gene co-expression network analysis. Quantitative real-time PCR (qRT-PCR) was used to detect the expression of miR-744-5p in OS cell lines. In vitro experiments, including CCK-8 assays, colony formation assays, flow cytometry apoptosis assays, and tube formation assays, were performed to explore the effects of miR-744-5p on OS cell biological behaviors. The downstream target genes of miR-744-5p were predicted through bioinformatics, and the binding sites were validated by a dual-luciferase reporter assay.ResultsThe lowly expressed miRNA, miR-744-5p, was identified as a hub miRNA involved in OS progression through bioinformatic analysis. Nuclear factor I X (NFIX) was confirmed as a direct target for miR-744-5p in OS. In vitro studies revealed that overexpression of miR-744-5p could restrain the growth of OS cells, whereas miR-744-5p inhibition showed the opposite effect. It was also observed that treatment with the conditioned medium from miR-744-5p-overexpressed OS cells led to poorer proliferation and angiogenesis in human umbilical vein endothelial cells (HUVECs). Furthermore, NFIX overexpression restored the suppression effects of miR-744-5p overexpression on OS cell growth and HUVECs angiogenesis.ConclusionOur results indicated that miR-744-5p is a potential tumor-suppressive miRNA in OS progression by targeting NFIX to restrain the growth of OS cells and angiogenesis in HUVECs.

Sponging of five tumour suppressor miRNAs by lncRNA-KCNQ1OT1 activates BMPR1A/BMPR1B-ACVR2A/ACVR2B signalling and promotes chemoresistance in hepatocellular carcinoma

Diverse mechanisms have been established to understand the chemoresistance of hepatocellular carcinoma (HCC), but the contribution of non-coding RNAs is not surveyed well. Here, we aimed to explore the lncRNA-miRNA axis in Hepatitis C and B virus (HCV and HBV) infected HCC to investigate the molecular mechanism of chemoresistance and to identify a potential therapeutic target for HCC. The small RNA transcriptome analysis followed by qRT-PCR validation with the liver tissues of both HCV and HBV infected HCC patients revealed that miR-424-5p, miR-136-3p, miR-139-5p, miR-223-3p, and miR-375-3p were the most downregulated miRNAs in HCC compared to normal (log2 fold change ≤−1.5, Padj ≤ 0.05). In silico pathway analysis with the validated targets of each miRNA revealed that the signalling pathway regulating pluripotency of stem cells is commonly targeted by these five miRNAs. Subsequent validation by 3′UTR-luciferase assay and western blot analysis unveiled that these five miRNAs impeded either same or diverse genes, but all linked to BMP signalling pathway such as BMPR1A/BMPR1B by miR-139-5p, miR-136-3p, and miR-375-3p, and ACVR2A/ACVR2B by miR-424-5p and miR-223-3p. Furthermore, restoration of each miRNA in Huh7/SNU449 cells inhibited phosphorylation of downstream SMAD1/5 and ERK1/2, and attenuated Epithelial-mesenchymal transition, stemness, spheroid formation, chemoresistance, invasion and migration of cells. To investigate the mechanism of suppression of these miRNAs, “DIANA” tool was employed and lncRNA-KCNQ1OT1 was retrieved as interacting partner of all the five miRNAs. In vitro RNA pull-down assay revealed that lncRNA-KCNQ1OT1 physically interacted and sequestered these five miRNAs in the cytoplasm. Hence, KCNQ1OT1 was suppressed in Huh7/SNU449 cells using CRISPR technology and observed regression of oncogenic properties with enhanced chemosensitivity and reduced metastasis in cancer cells. Shrinkage of tumour size and volume in NOD-SCID mice injected with KCNQ1OT1-sgRNA cells further strengthened our observations. Thus, lncRNA-KCNQ1OT1 is the main regulator, which reduces the level of beneficiary miRNAs in the tumour milieu and modulates BMP signalling pathway to promote chemoresistance in HCC, suggesting lncRNA-KCNQ1OT1 might have robust potential to be a therapeutic target in HCC.