MicroRNA-101 inhibits cell proliferation and induces apoptosis by targeting EYA1 in breast cancer

EYA3 promotes the tumorigenesis of gastric cancer through activation of the mTORC1 signaling pathway and inhibition of autophagy

Gastric cancer (GC) is a leading cause of cancer-related mortality, with a high rate of postoperative recurrence and poor long-term survival. The Eyes Absent (EYA) protein family plays a significant role in cancer progression, with EYA3 being implicated in promoting GC cell proliferation and tumor growth. Utilizing the DepMap database, we identified EYA3 as a gene of interest in GC. We analyzed EYA3 expression in GC tissues and cell lines, performed in vitro assays to assess its role in cell proliferation, and conducted gene set enrichment analysis to explore its relationship with autophagy and the mTORC1 signaling pathway. In vivo, we used a xenograft tumor model to examine the effects of EYA3 expression on tumor progression. EYA3 was consistently upregulated in GC tissues, and its high expression correlated with a decrease in patient survival rates. Silencing EYA3 in GC cell lines resulted in reduced cell proliferation. Inhibition of autophagy and activation of the mTORC1 signaling pathway were observed as mechanisms by which EYA3 may promote GC cell growth. In vivo experiments supported the in vitro findings, showing slower tumor growth with reduced EYA3 expression. Our study confirms the upregulation of EYA3 in GC and its association with poor prognosis. EYA3 promotes GC cell proliferation and tumor growth by activating the mTORC1 signaling pathway and inhibiting autophagy. These findings highlight the potential of EYA3 as a therapeutic target for GC, providing a foundation for future research and treatment strategies. Despite the promising data, the limitations of sample size and the need for further mechanistic studies are acknowledged.

Differential effects of docosahexaenoic acid (DHA) and linoleic acid (LA) on miR-101 and miR-342 tumor suppressor microRNAs in Taxol-treated HER2-positive breast cancer cells

BACKGROUND & AIMS

Docosahexaenoic acid (DHA) and linoleic acid (LA) have been shown to exhibit anti-proliferative effects against breast cancer cells. However, the mechanisms underlying these effects are not yet fully understood. One potential mechanism is through the regulation of microRNAs (miRs), which are known to play a crucial role in breast cancer development and progression. This study aimed to investigate the expression of miR-342 and miR-101 as tumor-suppressor miRs in the human HER-2 positive breast cancer cell line BT-474 after treatment with DHA, LA, alone or in combination with Taxol, a standard chemotherapy agent.

METHODS

The human breast cancer cell line BT-474 was cultured, and the IC50 for Taxol was determined using the MTT assay. Cells were then cultured and treated for 24 h with 100 μM DHA and 50 μM LA, alone or in combination with the respective IC50 of Taxol. Cells were harvested, and miRNA extraction and cDNA synthesis were performed using standard methods. Expression levels of miRs were analyzed using quantitative real-time PCR (qRT-PCR), and results were normalized against U6 snRNA expression levels.

RESULTS

The Taxol IC50 for BT-474 cells was 19 nM. According to the data obtained from our study, it was observed that Taxol treatment resulted in the down-regulation of both miR-101 and miR-342 (3.69 (p < 0.0001) and 1.88 fold, (p < 0.0001) respectively). In addition, DHA, LA and DHA + LA caused up-regulation of miR-101 (0.11, 0.05, 0.03 fold (p < 0.0001) respectively) but not miR-342 (decreased by 1.93 (p < 0.0001), 2.89 (p < 0.0001) and 1.19 fold (p = 0.0029) respectively). Notably, treatment with DHA, LA and DHA + LA was able to restore the down-regulated expression of miR-101 (0.25 (p < 0.0001), 0.05 (p = 0.0012) and 0.06 fold (p < 0.0001) respectively) during Taxol treatment.

CONCLUSION

Our study demonstrates that DHA and LA can effectively compensate for the reduced expression of miR-101 during Taxol treatment. These findings suggest that dietary fatty acids may play a critical role in modulating the anti-cancer effects of chemotherapy agents. Future studies are needed to investigate the functional aspects of dietary fatty acids on breast cancer development and progression.

Stem Cell Division and Its Critical Role in Mammary Gland Development and Tumorigenesis: Current Progress and Remaining Challenges

The origin of breast cancer (BC) has traditionally been a focus of medical research. It is widely acknowledged that BC originates from immortal mammary stem cells and that these stem cells participate in two division modes: symmetric cell division (SCD) and asymmetrical cell division (ACD). Although both of these modes are key to the process of breast development and their imbalance is closely associated with the onset of BC, the molecular mechanisms underlying these phenomena deserve in-depth exploration. In this review, we first outline the molecular mechanisms governing ACD/SCD and analyze the role of ACD/SCD in various stages of breast development. We describe that the changes in telomerase activity, the role of polar proteins, and the stimulation of ovarian hormones subsequently lead to two distinct consequences: breast development or carcinogenesis. Finally, gene mutations, abnormalities in polar proteins, modulation of signal-transduction pathways, and alterations in the microenvironment disrupt the balance of BC stem cell division modes and cause BC. Important regulatory factors such as mammalian Inscuteable mInsc, Numb, Eya1, PKCα, PKCθ, p53, and IL-6 also play significant roles in regulating pathways of ACD/SCD and may constitute key targets for future research on stem cell division, breast development, and tumor therapy.

Regulation of the Cell Cycle by ncRNAs Affects the Efficiency of CDK4/6 Inhibition

Cyclin-dependent kinases (CDKs) regulate cell division at multiple levels. Aberrant proliferation induced by abnormal cell cycle is a hallmark of cancer. Over the past few decades, several drugs that inhibit CDK activity have been created to stop the development of cancer cells. The third generation of selective CDK4/6 inhibition has proceeded into clinical trials for a range of cancers and is quickly becoming the backbone of contemporary cancer therapy. Non-coding RNAs, or ncRNAs, do not encode proteins. Many studies have demonstrated the involvement of ncRNAs in the regulation of the cell cycle and their abnormal expression in cancer. By interacting with important cell cycle regulators, preclinical studies have demonstrated that ncRNAs may decrease or increase the treatment outcome of CDK4/6 inhibition. As a result, cell cycle-associated ncRNAs may act as predictors of CDK4/6 inhibition efficacy and perhaps present novel candidates for tumor therapy and diagnosis.

MiR-101: An Important Regulator of Gene Expression and Tumor Ecosystem

MiRNAs are small single-stranded non-coding RNAs. MiRNA contributes to the transcriptional and post-transcriptional regulation of mRNA in different cell types, including mRNA transcription inhibition and mRNA decay and phenotypes via the effect of several essential oncogenic processes and tumor microenvironment. MiR-101 is a highly conserved miRNA that was found to alter the expression in various human cancers. MiR-101 has been reported to have tumor oncogenic and suppressive effects to regulate tumorigenesis and tumor progression. In this review, we summarize the new findings about the roles of miR-101 in cancers and the underlying mechanisms of targeting genes degradation and microenvironment regulation, which will improve biological understanding and design of novel therapeutics.

The role of epigenetic modifications in drug resistance and treatment of breast cancer

Background

Breast cancer is defined as a biological and molecular heterogeneous disorder that originates from breast cells. Genetic predisposition is the most important factor giving rise to this malignancy. The most notable mutations in breast cancer occur in the BRCA1 and BRCA2 genes. Owing to disease heterogeneity, lack of therapeutic target, anti-cancer drug resistance, residual disease, and recurrence, researchers are faced with challenges in developing strategies to treat patients with breast cancer.

Results

It has recently been reported that epigenetic processes such as DNA methylation and histone modification, as well as microRNAs (miRNAs), have potently contributed to the pathophysiology, diagnosis, and treatment of breast cancer. These observations have persuaded researchers to move their therapeutic approaches beyond the genetic framework toward the epigenetic concept.

Conclusion

Herein we discuss the molecular and epigenetic mechanisms underlying breast cancer progression and resistance as well as various aspects of epigenetic-based therapies as monotherapy and combined with immunotherapy.

Significance of Cyclooxgenase-2 gene polymorphism and related miRNAs in pulmonary arterial hypertension

BACKGROUND

Pulmonary arterial hypertension (PAH) is a rare disease with a poor prognosis. The suppression of cyclooxygenase-2 (COX-2) expression has been known to impair vascular function in endothelial cells; however, the epigenetic factors that cause this are largely obscure. Our aim in this study was to examine the polymorphisms in the gene for COX-2 (PTGS2) and related miRNAs regulating its level in a single-center cohort of patients with PAH.

METHOD

In this study, three SNPs and miRNAs (rs5275, rs689470, rs20417, miR-26b-5p, miR-146a-5p, and miR-101-5p) in the PTGS2 were screened in PAH and controls by qPCR. In addition, the COX-2 level was determined by immunoassay to examine the effects of epigenetic factors on its expression levels.

RESULTS

The non-dominant genotypes of rs20417 and rs5275 were found to be related to PAH (OR = 8.56, 95% CI = 3.39-21.63, p < 0.0001 and OR = 7.82, 95% CI = 3.30-18.53, p < 0.0001, respectively). We also observed a significant increase in the miR-26b-5p and miR-146a-5p levels in PAH patients (2.18 and 2.35-fold, respectively; for both, p < 0.05). In addition, it was found that SNPs influenced the COX-2, miR-26b-5p, and miR-146a-5p levels in PAH. A negative correlation was also found between COX-2 levels and miR-26b-5p and miR-146a-5p.

CONCLUSIONS

As conventional drug therapies may cause lower COX-2 levels, the development of new genetic or epigenetic biomarkers is crucially important for early diagnosis and prognosis. The presence of minor alleles for rs5275 and rs689470 might also be considered as a significant risk factor for developing PAH. Furthermore, locus-specific miRNAs, such as miR-26b-5p and miR-146a-5p, seem to play a critical role in the regulation of PTGS2 expression.

miR-101-5p Acts as a Tumor Suppressor in HER2-Positive Breast Cancer Cells and Improves Targeted Therapy

Purpose

Human epidermal growth factor receptor 2 positive (HER2+) breast cancers responding poorly to targeted therapy need improved treatment options. miR-101-5p has shown tumor-suppressive properties in multiple cancer forms, and we assessed the effect and mechanism of action of this miRNA in HER2+ breast cancer.

Methods

Expression levels of miR-101-5p in two clinical datasets, TCGA and METABRIC, were compared between tumor and normal adjacent samples, and across molecular subtypes and HER2 status. The ability of miR-101-5p to sensitize for treatment with lapatinib, tucatinib and trastuzumab was explored in HER2+ breast cancer cells responding poorly to such targeted drugs. Proliferation and apoptosis assays and downstream protein analysis were performed.

Results

Expression levels of miR-101-5p were significantly lower in tumor compared to normal adjacent tissue (p < 0.001), and particularly low in HER2+ tumors, both the HER2-enriched subtype (p ≤ 0.037) and clinical HER2-status (p < 0.001). In a HER2+ cell line (KPL4) responding poorly to targeted drugs, miR-101-5p overexpression inhibited proliferation (p < 0.001), and combinatorial treatment with lapatinib and trastuzumab significantly further decreased this inhibition (p = 0.004). Proteomic data and in silico analyses revealed PI3K/Akt- and HER2-pathways among the predicted regulated pathways. miR-101-5p alone (p = 0.018) and in combination with lapatinib and trastuzumab (p < 0.001) induced apoptosis, while the targeted drugs alone did not exert any significant effect neither on proliferation nor apoptosis.

Conclusion

miR-101-5p acts as a tumor suppressor by inducing apoptosis in HER2+ breast cancer and sensitizes cells with initially poor response to lapatinib and trastuzumab.

Cytochrome b561 Serves as a Potential Prognostic Biomarker and Target for Breast Cancer

PURPOSE

Cytochrome b561 (CYB561) is a transmembrane protein and participates in ascorbate recycling and iron homeostasis. However, its role in breast cancer remains unclear.

PATIENTS AND METHODS

In this study, we explored the expression pattern and prognostic value of CYB561 in breast cancer through The Cancer Genome Atlas (TCGA), Gene Expression Omnibus (GEO), PrognoScan and Kaplan-Meier Plotter and confirmed its mRNA expression in human breast cell lines. LinkedOmics, Metascape and Gene Expression Profiling Interactive Analysis (GEPIA2) databases were applied to investigate the co-expression genes and construct microRNA (miRNA) networks associated with CYB561. The correlations between CYB561 and immune infiltration cells and genes were also illustrated.

RESULTS

The CYB561 expression was upregulated in breast cancer tissues and cell lines and significantly correlated with the clinical features of breast cancer patients. High CYB561 expression was associated with poor survival and was an independent risk factor for overall and disease-specific survival. Functional enrichment analysis showed that CYB561 and its co-expressed genes were mainly enriched in lipid biosynthetic process, Wnt signaling pathway, Hippo signaling pathway, etc. The miRNA network analysis suggested that hsa-miR-497 was negatively correlated with CYB561 expression and was predicted to direct target CYB561. CYB561 expression was positively correlated with infiltrating levels of CD4+ T cells, neutrophils and dendritic cells in breast cancer. Subsequent analysis found that B cells could predict the outcome of breast cancer. Also, CYB561 showed strong correlations with diverse immune marker sets in breast cancer.

CONCLUSION

CYB561 may serve as a potential prognostic biomarker and target for breast cancer. Our findings laid foundation for future research on molecular mechanisms of CYB561 in breast cancer.

Epi-miRNAs: Regulators of the Histone Modification Machinery in Human Cancer

Cancer is a leading cause of death and disability worldwide. Epigenetic deregulation is one of the most critical mechanisms in carcinogenesis and can be classified into effects on DNA methylation and histone modification. MicroRNAs are small noncoding RNAs involved in fine-tuning their target genes after transcription. Various microRNAs control the expression of histone modifiers and are involved in a variety of cancers. Therefore, overexpression or downregulation of microRNAs can alter cell fate and cause malignancies. In this review, we discuss the role of microRNAs in regulating the histone modification machinery in various cancers, with a focus on the histone-modifying enzymes such as acetylases, deacetylases, methyltransferases, demethylases, kinases, phosphatases, desumoylases, ubiquitinases, and deubiquitinases. Understanding of microRNA-related aberrations underlying histone modifiers in pathogenesis of different cancers can help identify novel therapeutic targets or early detection approaches that allow better management of patients or monitoring of treatment response.

Is the regulation by miRNAs of NTPDase1 and ecto-5'-nucleotidase genes involved with the different profiles of breast cancer subtypes?

Breast cancer (BC) is a public health problem worldwide, causing suffering and premature death among women. As a heterogeneous disease, BC-specific diagnosis and treatment are challenging. Ectonucleotidases are related to tumor development and their expression may vary among BC. miRNAs may participate in epigenetic events and may regulate ectonucleotidases in BC. This study aimed to evaluate the expression of ectonucleotidases according to BC subtypes and to predict if there is post-transcriptional regulation of them by miRNAs. MCF 10A (non-tumorigenic), MCF7 (luminal BC), and MDA-MB-231 (triple-negative BC - TNBC) breast cell lines were used and ENTPD1 (the gene encoding for NTPDase1) and NT5E (the gene encoding for ecto-5'-nucleotidase) gene expression was determined. Interestingly, the expression of ENTPD1 was only observed in MCF7 and NT5E was lower in MCF7 compared to MDA-MB-231 cell line. ATP, ADP, and AMP hydrolysis were observed on the surface of all cell lines, being higher in MDA-MB-231. Like qPCR, the activity of AMP hydrolysis was also lower in the MCF7 cells, which may represent a striking feature of this BC subtype. In silico analyses confirmed that the miRNAs miR-101-3p, miR-141-3p, and miR-340-5p were higher expressed in MCF7 cells and targeted NT5E mRNA. Altogether, data suggest that the regulation of NT5E by miRNAs in MCF7 lineage may direct the molecular profile of luminal BC. Thus, we suggest that the roles of ecto-5'-nucleotidase and the aforementioned miRNAs must be unraveled in TNBC to be possibly defined as diagnostic and therapeutic targets.

Maternal Nutrition During Gestation Alters Histochemical Properties, and mRNA and microRNA Expression in Adipose Tissue of Wagyu Fetuses

We hypothesized that maternal low or high nutrition would give unique effects to morphological and molecular dynamics in adipose tissue of fetus of fatty breed Wagyu (Japanese Black) cattle which produce highly marbled beef. This study aimed to determine the effects of maternal energy intake in Wagyu cows, during gestation on fetal adipose tissue development, histochemical properties, and gene and microRNA (miRNA) expression. Cows were allocated to one of two nutritional energy groups: 120% (HIGH) or 60% nutritional requirements of (LOW). Fetuses (n = 6 per treatment) were removed from pregnant cows by cesarean section at fetal age 260 ± 8 days and euthanized. Subcutaneous adipose tissue (SAT), thoracic cavity visceral adipose tissue (TVAT), and perirenal adipose tissue (PAT) were collected for analysis. In histochemical analysis, in SAT and PAT, HIGH fetuses had greater diameter of adipocytes than LOW fetuses (P<0.05). Only in SAT, LOW fetuses had more Leptin (LEP) mRNA and tended to have more Peroxisome Proliferator-Activated Receptor gamma (PPARG) CCAAT-enhancer-binding proteins alpha (CEBPA) and Glucose transporter (GLUT) 4 mRNA(P<0.10). In all SAT, TVAT, and PAT, LOW fetuses had higher levels of the brown adipose tissue (BAT) biomarkers Uncoupling Protein (UCP) 1 and PPARG coactivator (PGC) 1α mRNA than HIGH fetuses (P<0.08). Meanwhile, in the other adipose tissue, LOW fetuses had lower PPARG, CEBPA, and Zinc Finger Protein (ZFP) 423 (in TVAT and PAT), FASN (in TVAT), LEP and GLUT4 mRNA (in PAT; P<0.10). In particular, in TVAT and PAT, LOW fetuses exhibited lower expression of WAT biomarkers (PPARG and ZFP423). Differential expression of various miRNAs related to adipogenesis between the LOW and HIGH fetuses was detected in an adipose tissue-specific manner (P<0.10). Based on adipose tissue-specific effects of maternal nutrition, these findings suggested that poor maternal nutrition in Wagyu cattle increased BAT development in SAT, TVAT and PAT, while elevated maternal nutrition stimulated fetal SAT development compared with that of TVAT and PAT.

The role of tumor suppressor short non-coding RNAs on breast cancer

Characterized by remarkable levels of aggression and malignancy, BC remains one of the leading causes of death in females world wide. Accordingly, significant efforts have been made to develop early diagnostic tools, increase treatment efficacy, and improve patient prognosis. Hopefully, many of the molecular mechanisms underlying BC have been detected and show promising targeting potential. In particular, short and long non-coding RNAs (ncRNAs) are a class of endogenous BC controllers and include a number of different species including microRNAs, Piwi-interacting RNAs, small nucleolar RNA, short interfering RNAs, and tRNA-derivatives. In this review, we discuss the tumor suppressing roles of ncRNAs in the context of BC, and the mechanisms by which ncRNAs target tumor hallmarks, including apoptosis, proliferation, invasion, metastasis, epithelial-mesenchymal transition, angiogenesis, and cell cycle progression, in addition to their diagnostic and prognostic significance in cancer treatment.

GPER1 and microRNA: Two Players in Breast Cancer Progression

Breast cancer is the main cause of morbidity and mortality in women worldwide. However, the molecular pathogenesis of breast cancer remains poorly defined due to its heterogeneity. Several studies have reported that G Protein-Coupled Estrogen Receptor 1 (GPER1) plays a crucial role in breast cancer progression, by binding to estrogens or synthetic agonists, like G-1, thus modulating genes involved in diverse biological events, such as cell proliferation, migration, apoptosis, and metastasis. In addition, it has been established that the dysregulation of short sequences of non-coding RNA, named microRNAs (miRNAs), is involved in various pathophysiological conditions, including breast cancer. Recent evidence has indicated that estrogens may regulate miRNA expression and therefore modulate the levels of their target genes, not only through the classical estrogen receptors (ERs), but also activating GPER1 signalling, hence suggesting an alternative molecular pathway involved in breast tumor progression. Here, the current knowledge about GPER1 and miRNA action in breast cancer is recapitulated, reporting recent evidence on the liaison of these two players in triggering breast tumorogenic effects. Elucidating the role of GPER1 and miRNAs in breast cancer might provide new tools for innovative approaches in anti-cancer therapy.

MiR-203a-3p Inhibits Pancreatic Cancer Cell Proliferation, EMT, and Apoptosis by Regulating SLUG

OBJECTIVE

The aim of the present research is to study the roles of miR-203a-3p on cell proliferation, migration, invasion, and epithelial-mesenchymal transition in pancreatic cancer.

METHODS

Transcription profiles were acquired from Gene Expression Omnibus database, which was used to screen out the differentially expressed microRNAs and messenger RNAs in pancreatic cancer. Pancreatic cancer tissues were used to verify the bioinformatics results by quantitative real-time polymerase chain reaction. The relationship between miR-203a-3p and SLUG was examined by TargetScan software, dual-luciferase reporter assay, and RNA immunoprecipitation. The Cell Counting Kit-8, wound healing, and transwell assays were conducted to investigate the proliferation, migration, and invasion capability of pancreatic cancer cells, respectively. The expression of epithelial-mesenchymal transition-related proteins was determined by the Western blot assay. Xenograft assay was performed to verify findings from in vitro assays.

RESULTS

Bioinformatic analysis found that a total of 113 microRNAs and 1749 messenger RNAs expressed differentially in pancreatic cancer tissues. Among these microRNAs, the expression of miR-203a-3p was significantly decreased in both pancreatic cancer tissues and cells. On the other hand, the SLUG expression was remarkably upregulated in pancreatic cancer tissues and cells in comparison with normal tissues and cells. Moreover, TargetScan software, dual-luciferase reporter assay, and RNA immunoprecipitation revealed that SLUG was a target of miR-203a-3p. The upregulation of miR-203a-3p expression inhibited the proliferation, migration, and invasion ability of pancreatic cancer cells by suppressing the epithelial-mesenchymal transition process via sponging SLUG.

CONCLUSION

These findings indicate that downregulation of miR-203a-3p in pancreatic cancer cells leads to high expression of SLUG, which promotes epithelial-mesenchymal transition process and induces cancer progression.

Circulating miRNAs in HER2-Positive and Triple Negative Breast Cancers: Potential Biomarkers and Therapeutic Targets

Breast cancer is one of the most prevalent diseases among women worldwide and is highly associated with cancer-related mortality. Of the four major molecular subtypes, HER2-positive and triple-negative breast cancer (TNBC) comprise more than 30% of all breast cancers. While the HER2-positive subtype lacks estrogen and progesterone receptors and overexpresses HER2, the TNBC subtype lacks estrogen, progesterone and HER2 receptors. Although advances in molecular biology and genetics have substantially ameliorated breast cancer disease management, targeted therapies for the treatment of estrogen-receptor negative breast cancer patients are still restricted, particularly for TNBC. On the other hand, it has been demonstrated that microRNAs, miRNAs or small non-coding RNAs that regulate gene expression are involved in diverse biological processes, including carcinogenesis. Moreover, circulating miRNAs in serum/plasma are among the most promising diagnostic/therapeutic tools as they are stable and relatively easy to quantify. Various circulating miRNAs have been identified in several human cancers including specific breast cancer subtypes. This review aims to discuss the role of circulating miRNAs as potential diagnostic and prognostic biomarkers as well as therapeutic targets for estrogen-receptor negative breast cancers, HER2+ and triple negative.

Downregulation of extracellular vesicle microRNA-101 derived from bone marrow mesenchymal stromal cells in myelodysplastic syndrome with disease progression

To evaluate the mechanism underlying the communication between myeloid malignant and bone marrow (BM) microenvironment cells in disease progression, the current study established BM mesenchymal stromal cells (MSCs) and assessed extracellular vesicle (EV) microRNA (miR) expression in 22 patients with myelodysplastic syndrome (MDS) and 7 patients with acute myeloid leukemia and myelodysplasia-related changes (AML/MRC). Patients with MDS were separated into two categories based on the revised International Prognostic Scoring System (IPSS-R), and EV-miR expression in BM-MSCs was evaluated using a TaqMan low-density array. The selected miRs were evaluated using reverse transcription-quantitative PCR. The current study demonstrated that the expression of BM-MSC-derived EV-miR was heterogenous and based on MDS severity, the expression of EV-miR-101 was lower in high-risk group and patients with AML/MRC compared with the control and low-risk groups. This reversibly correlated with BM blast percentage, with which the cellular miR-101 from BM-MSCs or serum EV-miR-101 expression exhibited no association. Database analyses indicated that miR-101 negatively regulated cell proliferation and epigenetic gene expression. The downregulation of BM-MSC-derived EV-miR-101 may be associated with cell-to-cell communication and may accelerate the malignant process in MDS cells.

miRNA-101 Targets TGF-βR1 to Retard the Progression of Oral Squamous Cell Carcinoma

Despite the considerable knowledge on the involvement of microRNA-101 (miR-101) in the evolution of oral squamous cell carcinoma (OSCC), the underlying mechanisms remain obscure. In this study, miR-101 expression was markedly downregulated in the OSCC cell lines and tissues. Cell counting kit-8 (CCK-8), ethynyl deoxyuridine (EdU), and colony formation assays showed that miR-101 inhibited the proliferation of OSCC cells. Flow cytometry and caspase 3 activity assays indicated that miR-101 induced OSCC cell apoptosis. Transwell assays demonstrated that this miRNA also repressed OSCC cell migration and invasion. Moreover, tube formation assay showed that miR-101 abated the proangiogenesis of OSCC cells. Dual-luciferase reporter assay confirmed that miR-101 directly targeted transforming growth factor-β receptor 1 (TGF-βR1) in OSCC. Ectopic expression of TGF-βR1 counteracted the effects of miR-101 on the OSCC cell characteristics. Thus, miR-101 significantly abolished the proliferation, motility, and proangiogenesis of OSCC cells and induced their apoptosis by targeting TGF-βR1. These results imply the potential application of miR-101 in OSCC treatment.

Chromatin protein PC4 is downregulated in breast cancer to promote disease progression: Implications of miR-29a

The human transcriptional coactivator PC4 has numerous roles to play in the cell. Other than its transcriptional coactivation function, it facilitates chromatin organization, DNA damage repair, viral DNA replication, etc. Although it was found to be an essential protein in vivo, the importance of this multifunctional protein in the regulation of different cellular pathways has not been investigated in details, particularly in oncogenesis. In this study, PC4 downregulation was observed in a significant proportion of mammary tissues obtained from Breast cancer patient samples as well as in a subset of highly invasive and metastatic Breast cancer patient-derived cell lines. We have identified a miRNA, miR-29a which potentially reduce the expression of PC4 both in RNA and protein level. This miR-29a was found to be indeed overexpressed in a substantial number of Breast cancer patient samples and cell lines as well, suggesting one of the key mechanisms of PC4 downregulation. Stable Knockdown of PC4 in MCF7 cells induced its migratory as well as invasive properties. Furthermore, in an orthotopic breast cancer mice model system; we have shown that reduced expression of PC4 enhances the tumorigenic potential substantially. Absence of PC4 led to the upregulation of several genes involved in Epithelial to Mesenchymal Transition (EMT), indicating the possible mechanism of uniform tumour progression in the orthotropic mice. Collectively these data establish the role of PC4 in tumour suppression.

MicroRNAs in breast cancer: Roles, functions, and mechanism of actions

Breast cancer is one of the most lethal malignancies in women in the world. Various factors are involved in the development and promotion of the malignancy; most of them involve changes in the expression of certain genes, such as microRNAs (miRNAs). MiRNAs can regulate signaling pathways negatively or positively, thereby affecting tumorigenesis and various aspects of cancer progression, particularly breast cancer. Besides, accumulating data demonstrated that miRNAs are a novel tool for prognosis and diagnosis of breast cancer patients. Herein, we will review the roles of these RNA molecules in several important signaling pathways, such as transforming growth factor, Wnt, Notch, nuclear factor-κ B, phosphoinositide-3-kinase/Akt, and extracellular-signal-regulated kinase/mitogen activated protein kinase signaling pathways in breast cancer.

LINC00511 as a ceRNA promotes cell malignant behaviors and correlates with prognosis of hepatocellular carcinoma patients by modulating miR-195/EYA1 axis

BACKGROUND

Recently, a growing number of reports indicated that long non-coding RNAs (lncRNAs) were involved in the development of various cancers. However, the performance of LINC00511 is still limited in hepatocellular carcinoma (HCC). Thus, we attempted to assess the effect of LINC00511 and underlying mechanism in HCC progression.

METHODS

TCGA and GEO database acted as supporters to provide us clinical samples data. Overall survival (OS) analyses were plotted using Kaplan-Meier method. Five cell lines were utilized to detect LINC00511 expression level and Cell Counting Kit-8 (CCK-8), colony formation and transwell assays were conducted to examine the effects on cell behaviors. The correlations between LINC00511 and miR-195 or eyes absent homolog 1 (EYA1) were confirmed by luciferase reporter assay. Quantitative real-time PCR and western blotting were fulfilled to ascertain the mRNA and protein expression levels.

RESULTS

In this study, we found that LINC00511 was high-regulated in HCC tissue samples and cell lines, which might be linked with unfavorable prognosis of HCC patients and clinical parameters. Loss-of-function experiments determined that LINC00511 deficiency inhibited cell proliferation, colony formation and invasive activity in HepG2 cells, while gain-of-function experiments showed the counter impacts in Huh7 cells. Bioinformatics tools and luciferase reporter assays revealed that LINC00511 may act as a competing endogenous RNA (ceRNA) for miR-195 and positively correlate with EYA1, which was reinforced by rescue experiments.

CONCLUSION

Taken together, these findings indicated that LINC00511 interacted with EYA1 promoted HCC development via mediating miR-195, proposing a promising therapeutic biomarker for HCC diagnosis and prognosis.

The Regulatory Role of MicroRNAs in Breast Cancer

MicroRNAs (miRNAs) are small non-coding RNA molecules which function as critical post-transcriptional gene regulators of various biological functions. Generally, miRNAs negatively regulate gene expression by binding to their selective messenger RNAs (mRNAs), thereby leading to either mRNA degradation or translational repression, depending on the degree of complementarity with target mRNA sequences. Aberrant expression of these miRNAs has been linked etiologically with various human diseases including breast cancer. Different cellular pathways of breast cancer development such as cell proliferation, apoptotic response, metastasis, cancer recurrence and chemoresistance are regulated by either the oncogenic miRNA (oncomiR) or tumor suppressor miRNA (tsmiR). In this review, we highlight the current state of research into miRNA involved in breast cancer, with particular attention to articles published between the years 2000 to 2019, using detailed searches of the databases PubMed, Google Scholar, and Scopus. The post-transcriptional gene regulatory roles of various dysregulated miRNAs in breast cancer and their potential as therapeutic targets are also discussed.

NOTCH signaling pathway and non-coding RNAs in cancer

Malignant tumors, known as cancer, seriously threaten human life and health. Cancer has the characteristics of abnormal cell differentiation, proliferation, invasion and metastasis. As a result, cancer often accompanied by poor prognosis and a lower survival rate. Notch signaling pathway is a highly conserved system in many multicellular organisms, and which has been proved to play a biological role in many cancers. In recent years, increasing evidence has shown that non-coding RNA can not only activate or inhibit NOTCH pathway, but also regulate the occurrence and development of cancer through NOTCH pathway. Therefore, we focus on the cancer-NOTCH-non-coding RNA axis in this review, and provide new ideas for cancer therapy.

Non-coding RNAs as potential therapeutic targets in breast cancer

Paradigm shifting studies especially involving non-coding RNAs (ncRNAs) during last few decades have significantly changed the scientific perspectives regarding the complexity of cellular signalling pathways. Several studies have shown that the non-coding RNAs, initially ignored as transcriptional noise or products of erroneous transcription; actually regulate plethora of biological phenomena ranging from developmental processes to various diseases including cancer. Current strategies that are employed for the management of various cancers including that of breast fall short when their undesired side effects like Cancer Stem Cells (CSC) enrichment, low recurrence-free survival and development of drug resistance are taken into consideration. This review aims at exploring the potential role of ncRNAs as therapeutics in breast cancer, by providing a comprehensive understanding of their mechanism of action and function and their crucial contribution in regulating various aspects of breast cancer progression such as cell proliferation, angiogenesis, EMT, CSCs, drug resistance and metastasis. In addition, we also provide information about various strategies that can be employed or are under development to explore them as potential moieties that may be used for therapeutic intervention in breast cancer.

MicroRNA‑4530 suppresses cell proliferation and induces apoptosis by targeting RASA1 in human umbilical vein endothelial cells

MicroRNAs (miRNAs/miRs) are a class of endogenous and non-coding RNAs that are present in eukaryotes. In previous studies, miRNAs have been revealed to have an important role in cell growth and apoptosis. In the present study, the function of a novel and rarely studied miRNA, miR-4530, was investigated in human umbilical vein endothelial cells (HUVECs). The expression level of miR-4530 in HUVECs was investigated using reverse transcription-quantitative polymerase chain reaction following transfection with miR-4530 precursor plasmids, anti-miR-4530 plasmids and empty vector plasmids. Following this, it was revealed that overexpression of miR-4530 can suppress cell proliferation and enhance cell apoptosis. TargetScan analysis suggested that Ras p21 protein activator 1 (RASA1) is a target gene of miR-4530. The results of a dual-luciferase reporter assay also suggested that miR-4530 targets RASA1. Furthermore, the results of dual-luciferase reporter assay suggested that miR-4530 enhanced luciferase activity of the wild-type reporter, but not the mutant RASA1 reporter activity, thus suggesting that miR-4530 enhances the expression of RASA1. In addition, western blot analysis demonstrated that the protein expression level of RASA1 was enhanced following upregulation of miR-4530. The exact mechanism underlying this process has not yet been determined and requires further investigation. In addition, a RASA1 overexpression plasmid vector was transfected into HUVECs. The results suggest that overexpression of RASA1 suppresses cell growth and promotes apoptosis, which was in agreement with the results regarding the overexpression of miR-4530. To investigate how miRNA-4530 affects cellular function, numerous proteins associated with the extracellular signal-regulated kinase (ERK)/mitogen-activated protein kinase (MAPK) and phosphoinositide 3-kinase (PI3K)/AKT serine/threonine kinase pathways were investigated via western blot analysis. The results suggested that miRNA-4530 suppresses cell proliferation and enhances apoptosis by targeting RASA1 via the ERK/MAPK and PI3K/AKT signaling pathways.

MiR-101 inhibits cell proliferation and invasion of pancreatic cancer through targeting STMN1

MiRNAs regulated most genes expression, which were proved important in various tumors. In this study, we want to investigate miR-101 effect and molecular mechanism on pancreatic cancer (PC), the research about this was blank now. RT-PCR analysis showed that miR-101 expression was declined in PC. MTT assay found that miR-101 mimic suppressed cell viability, while suppressing miR-101 facilitated cell proliferation. Transwell assay showed that miR-101 mimic inhibited cell invasion, but promoted cell invasion by miR-101 inhibitor. With TargetScanHuman's help, we verified STMN1 as a specific target of miR-101 and luciferase reporter assay was carried out to further confirm this discovery. STMN1 expression was reduced by miR-101 mimic and increased by miR-101 inhibitor. We next found that STMN1 was elevated in PC and its expression was negatively correlated with miR-101 expression. Furthermore, STMN1 siRNA curbed cell proliferation and invasion, which was opposite to miR-101 inhibitor effect on PC progression and STMN1 siRNA attenuated miR-101 inhibitor effect on cell proliferation and invasion. In conclusion, miR-101 inhibited PC cell proliferation and invasion via regulating STMN1, which provided a potential therapeutic for PC patients.

Oncogenic and Tumor-Suppressive Roles of MicroRNAs with Special Reference to Apoptosis: Molecular Mechanisms and Therapeutic Potential

MicroRNAs (miRNAs) are the non-coding class of minute RNA molecules that negatively control post-transcriptional regulation of various functional genes. These miRNAs are transcribed from the loci present in the introns of functional or protein-coding genes, exons of non-coding genes, or even in the 3'-untranslated region (3'-UTR). They have potential to modulate the stability or translational efficiency of a variety of target RNA [messenger RNA (mRNA)]. The regulatory function of miRNAs has been elucidated in several pathological conditions, including neurological (Alzheimer's disease and Parkinson's disease) and cardiovascular conditions, along with cancer. Importantly, miRNA identification in cancer progression and invasion has evolved as an incipient era in cancer treatment. Several studies have shown the influence of miRNAs on various cancer processes, including apoptosis, invasion, metastasis and angiogenesis. In particular, apoptosis induction in tumor cells through miRNA has been extensively studied. The biphasic mode (up- and down-regulation) of miRNA expression in apoptosis and other cancer processes has already been determined. The findings of these studies could be utilized to develop potential therapeutic strategies for the management of various cancers. The present review critically describes the oncogenic and tumor suppressor role of miRNAs in apoptosis and other cancer processes, therapy resistance, and use of their presence in the body fluids as biomarkers.

Non-coding RNAs in Various Stages of Liver Disease Leading to Hepatocellular Carcinoma: Differential Expression of miRNAs, piRNAs, lncRNAs, circRNAs, and sno/mt-RNAs

Hepatocellular carcinoma (HCC) was the fifth leading cause of cancer death in men and eighth leading cause of death in women in the United States in 2017. In our study, we sought to identify sncRNAs in various stages of development of HCC. We obtained publicly available small RNA-seq data derived from patients with cirrhosis (n = 14), low-grade dysplastic nodules (LGDN, n = 9), high grade dysplastic nodules (HGDN, n = 6), early hepatocellular carcinoma (eHCC, n = 6), and advanced hepatocellular carcinoma (HCC, n = 20), along with healthy liver tissue samples (n = 9). All samples were analyzed for various types of non-coding RNAs using PartekFlow software. We remapped small RNA-seq to miRBase to obtain differential expressions of miRNAs and found 87 in cirrhosis, 106 in LGDN, 59 in HGDN, 80 in eHCC, and 133 in HCC. Pathway analysis of miRNAs obtained from diseased samples compared to normal samples showed signaling pathways in the microRNA dependent EMT, CD44, and others. Additionally, we analyzed the data sets for piRNAs, lncRNAs, circRNAs, and sno/mt-RNAs. We validated the in silico data using human HCC samples with NanoString miRNA global expression. Our results suggest that publically available data is a valuable resource for sncRNA identification in HCC progression (FDR set to <0.05 for all samples) and that a data mining approach is useful for biomarker development.

Measuring plasma levels of three microRNAs can improve the accuracy for identification of malignant breast lesions in women with BI-RADS 4 mammography

A BI-RADS category of 4 from a mammogram indicates suspicious breast lesions, which require core biopsies for diagnosis and have an approximately one third chance of being malignant. Human plasma contains many circulating microRNAs, and variations in their circulating levels have been associated with pathologies, including cancer. Here, we present a novel methodology to identify malignant breast lesions in women with BI-RADS 4 mammography. First, we used the miRNome array and qRT-PCR to define circulating microRNAs that were differentially represented in blood samples from women with breast tumor (BI-RADS 5 or 6) in comparison to controls (BI-RADS 1 or 2). Next, we used qRT-PCR to quantify the level of this circulating microRNAs in patients with mammograms presenting with BI-RADS category 4. Finally, we developed a machine learning method (Artificial Neural Network - ANN) that receives circulating microRNA levels and automatically classifies BI-RADS 4 breast lesions as malignant or benign. We identified a minimum set of three circulating miRNAs (miR-15a, miR-101 and miR-144) with altered levels in patients with breast cancer. These three miRNAs were quantified in plasma from 60 patients presenting biopsy-proven BI-RADS 4 lesions. Finally, we constructed a very efficient ANN that could correctly classify BI-RADS 4 lesions as malignant or benign with approximately 92.5% accuracy, 95% specificity and 88% sensibility. We believe that our strategy of using circulating microRNA and a machine learning method to classify BI-RADS 4 breast lesions is a non-invasive, non-stressful and valuable complementary approach to core biopsy in women with BI-RADS 4 lesions.

1,25D3 differentially suppresses bladder cancer cell migration and invasion through the induction of miR-101-3p

Metastasis is the major cause of bladder cancer death. 1,25D3, the active metabolite of vitamin D, has shown anti-metastasis activity in several cancer model systems. However, the role of 1,25D3 in migration and invasion in bladder cancer is unknown. To investigate whether 1,25D3 affects migration and invasion, four human bladder cell lines with different reported invasiveness were selected: low-invasive T24 and 253J cells and highly invasive 253J-BV and TCCSUP cells. All of the four bladder cancer cells express endogenous and inducible vitamin D receptor (VDR) as examined by immunoblot analysis. 1,25D3 had no effect on the proliferation of bladder cancer cells as assessed by MTT assay. In contrast, 1,25D3 suppressed migration and invasion in the more invasive 253J-BV and TCCSUP cells, but not in the low-invasive 253J and T24 cells using "wound" healing, chemotactic migration and Matrigel-based invasion assays. 1,25D3 promoted the expression of miR-101-3p and miR-126-3p in 253J-BV cells as examined by qRT-PCR. miR-101-3p inhibitor partially abrogated and pre-miR-101-3p further suppressed the inhibition of 1,25D3 on migration and invasion in 253J-BV cells. Further, 1,25D3 enhanced VDR recruitment to the promoter region of miR-101-3p using ChIP-qPCR assay. 1,25D3 enhanced the promoter activity of miR-101-3p as evaluated by luciferase reporter assay. Taken together, 1,25D3 suppresses bladder cancer cell migration and invasion in two invasive/migration competent lines but not in two less invasive/motile lines, which is partially through the induction of miR-101-3p expression at the transcriptional level.

Clinical Value of miR-101-3p and Biological Analysis of its Prospective Targets in Breast Cancer: A Study Based on The Cancer Genome Atlas (TCGA) and Bioinformatics

Background

MiR-101-3p can promote apoptosis and inhibit proliferation, invasion, and metastasis in breast cancer (BC) cells. However, its mechanisms in BC are not fully understood. Therefore, a comprehensive analysis of the target genes, pathways, and networks of miR-101-3p in BC is necessary.

Material/Methods

The miR-101 profiles for 781 patients with BC from The Cancer Genome Atlas (TCGA) were analyzed. Gene expression profiling of GSE31397 with miR-101-3p transfected MCF-7 cells and scramble control cells was downloaded from Gene Expression Omnibus (GEO), and the differentially expressed genes (DEGs) were identified. The potential genes targeted by miR-101-3p were also predicted. Gene Ontology (GO) and pathway and network analyses were constructed for the DEGs and predicted genes.

Results

In the TCGA data, a low level of miR-101-2 expression might represent a diagnostic (AUC: 0.63) marker, and the miR-101-1 was a prognostic (HR=1.79) marker. MiR-101-1 was linked to the estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2), and miR-101-2 was associated with the tumor (T), lymph node (N), and metastasis (M) stages of BC. Moreover, 427 genes were selected from the 921 DEGs in GEO and the 7924 potential target genes from the prediction databases. These genes were related to transcription, metabolism, biosynthesis, and proliferation. The results were also significantly enriched in the VEGF, mTOR, focal adhesion, Wnt, and chemokine signaling pathways.

Conclusions

MiR-101-1 and miR-101-2 may be prospective biomarkers for the prognosis and diagnosis of BC, respectively, and are associated with diverse clinical parameters. The target genes of miR-101-3p regulate the development and progression of BC. These results provide insight into the pathogenic mechanism and potential therapies for BC.

Identification of Significant Pathways Induced by PAX5 Haploinsufficiency Based on Protein-Protein Interaction Networks and Cluster Analysis in Raji Cell Line

PAX5 encodes a transcription factor essential for B-cell differentiation, and PAX5 haploinsufficiency is involved in tumorigenesis. There were few studies on how PAX5 haploinsufficiency regulated genes expression to promote tumorigenesis. In this study, we constructed the cell model of PAX5 haploinsufficiency using gene editing technology in Raji cells, detected differentially expressed genes in PAX5 haploinsufficiency Raji cells, and used protein-protein interaction networks and cluster analysis to comprehensively investigate the cellular pathways involved in PAX5 haploinsufficiency. The clusters of gene transcription, inflammatory and immune response, and cancer pathways were identified as three important pathways associated with PAX5 haploinsufficiency in Raji cells. These changes hinted that the mechanism of PAX5 haploinsufficiency promoting tumorigenesis may be related to genomic instability, immune tolerance, and tumor pathways.