Upregulated miR-1258 regulates cell cycle and inhibits cell proliferation by directly targeting E2F8 in CRC

Prostate cancer and the cell cycle: Focusing on the role of microRNAs

Prostate cancer is the most frequent solid tumor in terms of incidence and ranks second only to lung cancer in terms of cancer mortality among men. It has a considerably high mortality rate; around 375,000 deaths occurred worldwide in 2020. In 2024, the American Cancer Society estimated that the number of new prostate cancer cases will be around 299,010 cases, and the estimated deaths will be around 32,250 deaths only in the USA. Cell cycle dysregulation is inevitable in cancer etiology and is targeted by various therapies in cancer treatment. MicroRNAs (miRNAs) are small, endogenous, non-coding regulatory molecules involved in both normal and abnormal cellular events. One of the cellular processes regulated by miRNAs is the cell cycle. Although there are some exceptions, tumor suppressor miRNAs could potentially arrest the cell cycle by downregulating several molecular machineries involved in catalyzing the cell cycle progression. In contrast, oncogenic miRNAs (oncomirs) help the cell cycle to progress by targeting various regulatory proteins such as retinoblastoma (Rb) or cell cycle inhibitors such as p21 or p27, and hence may contribute to prostate cancer progression; however, this is not always the case. In this review, we emphasize how a dysregulated miRNA expression profile is linked to an abnormal cell cycle progression in prostate cancer, which subsequently paves the way to a new therapeutic option for prostate cancer.

PTGR1-mediated immune evasion mechanisms in late-stage triple-negative breast cancer: mechanisms of M2 macrophage infiltration and CD8+ T cell suppression

Triple-negative breast cancer (TNBC) is a heterogeneous disease characterized by metabolic dysregulation. Tumor cell immune escape plays an indispensable role in the development of TNBC tumors. Furthermore, in the abstract, we explicitly mention the techniques used and enhance the clarity and impact of our findings. "Based on bioinformatics analysis results, we utilized CRISPR/Cas9 technology to knockout the target gene and established a mouse model of breast cancer. Through experiments such as CCK8, scratch assay, and Transwell assay, we further investigated the impact of target gene knockout on the malignant behavior of tumor cells. Subsequently, we conducted immunohistochemistry and Western Blot experiments to study the expression of macrophage polarization and infiltration-related markers and evaluate the effect of the target gene on macrophage polarization. Next, through co-culture experiments, we simulated the tumor microenvironment and used immunohistochemistry staining to observe and analyze the distribution and activation status of M2 macrophages and CD8+ T cells in the co-culture system. We validated in vivo experiments the molecular mechanism by which the target gene regulates immune cell impact on TNBC progression.

Single-cell RNA sequencing reveals special basal cells and fibroblasts in idiopathic pulmonary fibrosis

Idiopathic pulmonary fibrosis (IPF) is the most predominant type of idiopathic interstitial pneumonia and has an increasing incidence, poor prognosis, and unclear pathogenesis. In order to investigate the molecular mechanisms underlying IPF further, we performed single-cell RNA sequencing analysis on three healthy controls and five IPF lung tissue samples. The results revealed a significant shift in epithelial cells (ECs) phenotypes in IPF, which may be attributed to the differentiation of alveolar type 2 cells to basal cells. In addition, several previously unrecognized basal cell subtypes were preliminarily identified, including extracellular matrix basal cells, which were increased in the IPF group. We identified a special population of fibroblasts that highly expressed extracellular matrix-related genes, POSTN, CTHRC1, COL3A1, COL5A2, and COL12A1. We propose that the close interaction between ECs and fibroblasts through ligand-receptor pairs may have a critical function in IPF development. Collectively, these outcomes provide innovative perspectives on the complexity and diversity of basal cells and fibroblasts in IPF and contribute to the understanding of possible mechanisms in pathological lung fibrosis.

Caffeic acid phenethyl ester promotes oxaliplatin sensitization in colon cancer by inhibiting autophagy

Colon cancer ranks as the third most prevalent form of cancer globally, with chemotherapy remaining the primary treatment modality. To mitigate drug resistance and minimize adverse effects associated with chemotherapy, selection of appropriate adjuvants assumes paramount importance. Caffeic acid phenethyl ester (CAPE), a naturally occurring compound derived from propolis, exhibits a diverse array of biological activities. We observed that the addition of CAPE significantly augmented the drug sensitivity of colon cancer cells to oxaliplatin. In SW480 and HCT116 cells, oxaliplatin combined with 10 µM CAPE reduced the IC50 of oxaliplatin from 14.24 ± 1.03 and 84.16 ± 3.02 µM to 2.11 ± 0.15 and 3.92 ± 0.17 µM, respectively. We then used proteomics to detect differentially expressed proteins in CAPE-treated SW480 cells and found that the main proteins showing changes in expression after CAPE treatment were p62 (SQSTM1) and LC3B (MAP1LC3B). Gene ontology analysis revealed that CAPE exerted antitumor and chemotherapy-sensitization effects through the autophagy pathway. We subsequently verified the differentially expressed proteins using immunoblotting. Simultaneously, the autophagy inhibitor bafilomycin A1 and the mCherry-EGFP-LC3 reporter gene were used as controls to detect the effect of CAPE on autophagy levels. Collectively, the results indicate that CAPE may exert antitumor and chemotherapy-sensitizing effects by inhibiting autophagy, offering novel insights for the development of potential chemosensitizing agents.

Deciphering the miRNA-mRNA Interaction Landscape between Breast Cancer and Triple-Negative Breast Cancer: An Integrated Bioinformatics Approach

Breast cancer (BC) is globally recognized as the second most prevalent form of cancer. It predominantly affects women and can be categorized into distinct types based on the overexpression of specific cancer receptors.The key receptors implicated in this context are the human epidermal growth factor receptor-2 (HER2), estrogen receptor (ER), and progesterone receptor (PR), alongside a particularly intricate subclass known as triple-negative breast cancer (TNBC). This subclassification is critical for the stratification of breast cancer and informs therapeutic decision-making processes. Due to a lack of therapeutic targets, such as growth factor receptors, TNBC is the most aggressive type. Hence, identifying targetable regulators such as miRNAs could pave the way for potential therapeutic interventions. To identify common differentially expressed mRNAs (DE-mRNAs) in BC, including TNBC, we leveraged two data sets from the GEO collection and The Cancer Genome Atlas (TCGA). Significant DE-mRNAs were identified through PPI, MCODE, CytoNCA, and CytoHubba analyses. Following this, miRNAs were predicted using mirDIP. We utilized GSE42568, GSE185645, and TCGA and identified 159 common DE-mRNAs. Using Cytoscape plug-ins, we identified the 10 most significant DE-mRNAs in BC. Using mirDIP, target miRNAs for 10 DE-mRNAs were identified. We conducted an advanced analysis on the TNBC GEO data set (GSE45498) to corroborate the significance of shared DE-mRNAs and DE-miRNAs in TNBC. We identified four downregulated DE-miRNAs, including hsa-miR-802, hsa-miR-1258, hsa-miR-548a-3p, and hsa-miR-2053, significantly associated with TNBC. Our study revealed significant miRNA-mRNA interactions, specifically hsa-miR-802/MELK, hsa-miR-1258/NCAPG, miR-548a-3p/CCNA2, and hsa-miR-2053/NUSAP1, in both BC and TNBC. The observed downregulation of hsa-miR-548a-3p is associated with diminished survival rates in BC patients, emphasizing their potential utility as prognostic indicators. Furthermore, the differential expression of mRNAs, including CCNB2, UBE2C, MELK, and KIF2C, correlates with reduced survival outcomes, signifying their critical role as potential targets for therapeutic intervention in both BC and TNBC. These findings highlight specific regulatory mechanisms that are potentially crucial for understanding and treating these cancer types.

LncRNA GAS5 Modulates the Progression of Glioma Through Repressing miR-135b-5p and Upregulating APC

Purpose

The main purpose of this paper is to explore the interaction between GAS5 and miR-135b-5p to understand their function in the metastasis, invasion, and proliferation of glioma. This may provide new ideas for the pathogenesis and treatment of glioma.

Patients and Methods

Western blotting assays and RT‑qPCR were employed to investigate the expression of related genes in glioma tissues or cell lines. CCK-8 was used to examine the impact of GAS5 on cell viability. Motile activities were adopted by the transwell and wound healing experiments. A double luciferase experiment was performed to elucidate transcriptional regulation.

Results

GAS5 showed low expression in glioma cells and tissues, and up-regulation of GAS5 could depress the invasion, proliferation, and metastasis of glioma. GAS5 negatively regulates miR-135b-5p, which can counteract the cellular effects caused by GAS5. APC was the target of miR-135b-5p, and GAS5 can regulate the expression of APC by sponging miR-135b-5p. APC overexpression reversed the effects of miR-135b-5p promotion on glioma cells, while miR-135b-5p has the opposite function. As a downstream target gene of GAS5, miR-135b-5p was negatively regulated by GAS5. The restoration of miR-135b-5p can remarkably reverse the impact of GAS5 on glioma cells. In addition, GAS5 increased the expression of APC in glioma cells by inhibiting miR-135b-5p.

Conclusion

GAS5 increased APC expression by restraining miR-135b-5p and partially blocked the progression of glioma, suggesting that it could be an advantageous therapeutic target for glioma intervention.

Pleiotrophin inhibited chondrogenic differentiation potential of dental pulp stem cells

OBJECTIVE

Studies have shown that the levels of pleiotrophin (PTN) are greatly elevated in the synovial fluid and cartilage in osteoarthritis. Therefore, the purpose of this study was to investigate the effect and mechanism of PTN on the chondrogenic differentiation of DPSCs in inflammatory and normal microenvironments.

MATERIALS AND METHODS

A lentiviral vector was used to deplete or overexpress PTN in DPSCs. The inflammatory microenvironment was simulated in vitro by the addition of IL-1β to the culture medium. The chondrogenic differentiation potential was assessed using Alcian Blue staining and the main chondrogenic markers. A dual-luciferase reporter assay was used to explore the relationship between miR-137 and PTN.

RESULTS

The results showed that 0.1 ng/mL IL-1β treatment during chondrogenic induction greatly impaired the chondrogenic differentiation of DPSCs. Supplementation with PTN and PTN overexpression inhibited chondrogenic differentiation of DPSCs, while PTN depletion promoted chondrogenic differentiation. MiR-137 negatively regulated the expression of PTN by binding to the 3'UTR of its mRNA. Moreover, miR-137 promoted chondrogenic differentiation of DPSCs in normal and inflammatory microenvironments.

CONCLUSION

Our results suggest that PTN may play an inhibitory role in the chondrogenic differentiation of DPSCs in normal and inflammatory microenvironments, which is regulated by miR-137.

α-Conotoxin recombinant protein ImI-AFP3 efficiently inhibits the growth and migration of lung cancer cells

α-Conotoxin ImI is a selective antagonist of alpha7 nicotinic acetylcholine receptor (α7 nAChR) that is involved in cancer development. Human alpha fetoprotein domain 3 (AFP3) is a prototype of anticancer agents. In an effort to design drugs for anticancer treatments, we fused the ImI peptide to AFP3 as a fusion protein for testing. The fusion protein (ImI-AFP3) was highly expressed in the insect Bac-to-Bac system. The purified fusion protein was found to have improved anticancer activity and synergized with the drug gefitinib to inhibit the growth and migration of A549 and NCI-H1299 lung cancer cells. Our data have demonstrated that the recombinant protein ImI-AFP3 is a promising candidate for drug development to suppress lung cancer cell growth, especially to suppress hepatoid adenocarcinoma of the lung (HAL) cell growth.

Unraveling the enigma of B cells in diffuse large B-cell lymphoma: unveiling cancer stem cell-like B cell subpopulation at single-cell resolution

Background

Diffuse large B-cell lymphoma (DLBCL) represents the most prevalent form of aggressive non-Hodgkin lymphoma. Despite receiving standard treatment, a subset of patients undergoes refractory or recurrent cases, wherein the involvement of cancer stem cells (CSCs) could be significant.

Methods

We comprehensively characterized B cell subpopulations using single-cell RNA sequencing data from three DLBCL samples and one normal lymph tissue. The CopyKat R package was employed to assess the malignancy of B cell subpopulations based on chromosomal copy number variations. CIBERSORTx software was utilized to estimate the proportions of B cell subpopulations in 230 DLBCL tissues. Furthermore, we employed the pySCENIC to identify key transcription factors that regulate the functionality of B cell subpopulations. By employing CellphoneDB, we elucidated the interplay among tumor microenvironment components within the B cell subpopulations. Finally, we validated our findings through immunofluorescence experiments.

Results

Our analysis revealed a specific cancer stem cell-like B cell subpopulation exhibiting self-renewal and multilineage differentiation capabilities based on the exploration of B cell subpopulations in DLBCL and normal lymph tissues at the single-cell level. Notably, a high infiltration of cancer stem cell-like B cells correlated with a poor prognosis, potentially due to immune evasion mediated by low expression of major histocompatibility complex molecules. Furthermore, we identified key transcription factor regulatory networks regulated by HMGB3, SAP30, and E2F8, which likely played crucial roles in the functional characterization of the cancer stem cell-like B cell subpopulation. The existence of cancer stem cell-like B cells in DLBCL was validated through immunofluorescent staining. Finally, cell communication between B cells and tumor-infiltrating T cell subgroups provided further insights into the functional characterization of the cancer stem cell-like B cell subpopulation.

Conclusions

Our research provides a systematic description of a specific cancer stem cell-like B cell subpopulation associated with a poor prognosis in DLBCL. This study enhances our understanding of CSCs and identifies potential therapeutic targets for refractory or recurrent DLBCL patients.

GTF2E2 downregulated by miR-340-5p inhibits the malignant progression of glioblastoma

Glioblastoma is the most common malignant tumor in the central nervous system. The general transcription factor IIE subunit beta (GTF2E2) is crucial for physiological and pathological functions, but its roles in the malignant biological function of glioma remain ambiguous. CCK-8, colony formation assays, TUNEL assays, cell migration assays, wound-healing assays, and xenograft model were established to investigate the biological functions of GTF2E2 both in vitro and in vivo. GTF2E2 was overexpressed in glioma and was associated with poor prognosis of glioma patients. Biological functions of GTF2E2 were investigated both in vitro and in vi0vo by multiple experiments. Moreover, we explored the possible mechanisms of GTF2E2. In our results, we demonstrated that GTF2E2 could be regulated by miR-340-5p directly or indirectly. CCND1 was transcriptionally affected by GTF2E2 and glioma progression was then regulated. Our data presented the overexpression of GTF2E2 in glioma and indicated the association between GTF2E2 and glioma prognosis. GTF2E2 was found to be regulated by miR-340-5p and thus affect downstream gene expressions and glioma progression. Our results indicate that GTF2E2 might be a potential target in the diagnosis and treatments of glioblastoma.

miR-765 targeting PDX1 impairs pancreatic β-cell function to induce type 2 diabetes

Type 2 diabetes (T2DM) is a chronic metabolism disorder with a symptom as pancreatic β-cell dysfunction. In this study, the bioinformatics analysis identified the key regulators (PDX1 and miR-765) in T2DM. By qRT-PCR and western blotting, miR-765 with high expression and PDX1 with low expression were observed in blood samples from T2DM patients and the T2DM cell model. Together with GSIS assay, CCK-8, TUNEL assay, glycolysis assay, and mitochondrial respiration assay, miR-765 overexpression impaired insulin secretion cell viability, glycolysis, and mitochondrial respiration, while enhanced cell apoptosis in pancreatic β-cell. The Luciferase reporter, RIP, and RNA pull-down assays showed that PDX1 was the target gene of miR-765 in pancreatic β-cell. Besides, the negative effect of miR-765 on pancreatic β-cell could be overturned by PDX1 overexpression. In conclusion, we confirmed that miR-765 could cause a detrimental effect on pancreatic β-cell survival and function by targeting PDX1, which might provide new insight for T2DM therapy.

Emerging role of E2F8 in human cancer

E2F8 is a multifaceted transcription factor that plays a crucial role in mediating the hallmarks of cancer, including sustaining proliferative signaling, resisting cell death, and activating invasion and metastasis. Aberrant E2F8 expression is associated with poor clinical outcomes in most human cancers. However, E2F8 also exhibits tumor-suppressing activity; thus, the role of E2F8 in cell-fate determination is unclear. In this review, we highlight the recent progress in understanding the role of E2F8 in human cancers, which will contribute to building a conceptual framework and broadening our knowledge pertaining to E2F8. This review provides insight into future challenges and perspectives regarding the translation of biological knowledge into therapeutic strategies for the treatment of cancer.

Identification and preliminary validation of synovial tissue-specific genes and their-mediated biological mechanisms in rheumatoid arthritis

BACKGROUND

Rheumatoid arthritis (RA) is a chronic inflammatory autoimmune disease. It is well known that the formation of positive feedback between synovial hyperplasia and inflammatory infiltration is intimately associated with the occurrence and development of RA. However, the exact mechanisms still remain unknown, making the early diagnosis and therapy of RA difficult. This study was designed to identify prospective diagnostic and therapeutic biomarkers, as well as their-mediated biological mechanisms in RA.

METHODS

Three microarray datasets (GSE36700, GSE77298 and GSE153015) and two RNA-sequencing datasets (GSE89408 and GSE112656) of synovial tissues, as well as three other microarray datasets (GSE101193, GSE134087 and GSE94519) of peripheral blood were downloaded for integrated analysis. The differently expressed genes (DEGs) were identified by "limma" package of R software. Then, weight gene co-expression analysis and gene set enrichment analysis were performed to investigate synovial tissue-specific genes and their-mediated biological mechanisms in RA. The expression of candidate genes and their diagnostic value for RA were verified by quantitative real-time PCR and receiver operating characteristic (ROC) curve, respectively. Relevant biological mechanisms were explored through cell proliferation and colony formation assay. The suggestive anti-RA compounds were discovered by CMap analysis.

RESULTS

We identified a total of 266 DEGs, which were mainly enriched in cellular proliferation and migration, infection and inflammatory immune signaling pathways. Bioinformatics analysis and molecular validation revealed 5 synovial tissue-specific genes, which exhibited excellent diagnostic value for RA. The infiltration level of immune cells in RA synovial tissue was significantly higher than that in control individuals. Moreover, preliminary molecular experiments suggested that these characteristic genes may be responsible for the high proliferation potential of RA fibroblast-like synoviocytes (FLSs). Finally, 8 small molecular compounds with anti-RA potential were obtained.

CONCLUSIONS

We have proposed 5 potential diagnostic and therapeutic biomarkers (CDK1, TTK, HMMR, DLGAP5, and SKA3) in synovial tissues that may contribute to the pathogenesis of RA. These findings may shed light on the early diagnosis and therapy of RA.

Construction and validation of a prognostic model based on ten signature cell cycle-related genes for early-stage lung squamous cell carcinoma

BACKGROUND

We performed a bioinformatics analysis to screen for cell cycle-related differentially expressed genes (DEGs) and constructed a model for the prognostic prediction of patients with early-stage lung squamous cell carcinoma (LSCC).

METHODS

From a gene expression omnibus (GEO) database, the GSE157011 dataset was randomly divided into an internal training group and an internal testing group at a 1:1 ratio, and the GSE30219, GSE37745, GSE42127, and GSE73403 datasets were merged as the external validation group. We performed single-sample gene set enrichment analysis (ssGSEA), univariate Cox analysis, and difference analysis, and identified 372 cell cycle-related genes. Additionally, we combined LASSO/Cox regression analysis to construct a prognostic model. Then, patients were divided into high-risk and low-risk groups according to risk scores. The internal testing group, discovery set, and external verification set were used to assess model reliability. We used a nomogram to predict patient prognoses based on clinical features and risk values. Clinical relevance analysis and the Human Protein Atlas (HPA) database were used to verify signature gene expression.

RESULTS

Ten cell cycle-related DEGs (EIF2B1, FSD1L, FSTL3, ORC3, HMMR, SETD6, PRELP, PIGW, HSD17B6, and GNG7) were identified and a model based on the internal training group constructed. From this, patients in the low-risk group had a higher survival rate when compared with the high-risk group. Time-dependent receiver operating characteristic (tROC) and Cox regression analyses showed the model was efficient and accurate. Clinical relevance analysis and the HPA database showed that DEGs were significantly dysregulated in LSCC tissue.

CONCLUSION

Our model predicted the prognosis of early-stage LSCC patients and demonstrated potential applications for clinical decision-making and individualized therapy.

PCR Techniques and Their Clinical Applications

Kary B. Mullis developed a revolutionary method name polymerase chain reaction (PCR) in 1983, which can synthesize new strand of DNA complementary to the template strand of DNA and produce billions of copies of a DNA fragment only in few hours. Denaturation, annealing, and extension are the three primary steps involved in the PCR process, which generally requires thermocyclers, DNA template, a pair of primers, Taq polymerase, nucleotides, buffers, etc. With the development of PCR, from traditional PCR, quantitative PCR, to next digital PCR, PCR has become a powerful tool in life sciences and medicine. Applications of PCR techniques for infectious diseases include specific or broad-spectrum pathogen detection, assessment and surveillance of emerging infections, early detection of biological threat agents, and antimicrobial resistance analysis. Applications of PCR techniques for genetic diseases include prenatal diagnosis and screening of neonatal genetic diseases. Applications of PCR techniques for cancer research include tumor-related gene detection. This chapter aimed to discuss about the different types of PCR techniques, including traditional PCR, quantitative PCR, digital PCR, etc., and their applications for rapid detection, mutation screen or diagnosis in infectious diseases, inherited diseases, cancer, and other diseases.

Transcription factor E2F8 is a therapeutic target in the basal-like subtype of breast cancer

Introduction

Tumorigenesis in breast cancers usually accompanied by the dysregulation of transcription factors (TFs). Abnormal amplification of TFs leads aberrant expression of its downstream target genes. However, breast cancers are heterogeneous disease with different subtypes that have distinguished clinical behaviours, and the identification of prognostic TFs may enable to provide diagnosis and treatment of breast cancer based on subtypes, especially in Basal-like breast cancer.

Methods

The RNA-sequencing was performed to screen differential TFs in breast cancer subtypes. The GEPIA dataset analysis was used to analyze the genes expression in invasive breast carcinoma. The expression of MYBL2, HOXC13, and E2F8 was verified by qRT-PCR assay in breast cancers. The depiction analysis of co-expressed proteins was revealed using the STRING datasets. The cellular infiltration level analysis by the TISIDB and TIMER databases. The transwell assay was performed to analyze cellular migration and invasion. CCK-8 assay was used to evaluate cellular drug susceptibility for docetaxel treatment. Predicted targeted drugs in breast cancers by GSCA Lite database online.

Results

Kaplan-Meier plotter suggested that high expression of both E2F8 and MYBL2 in Basal-like subtype had a poor relapse-free survival. Functional enrichment results identified that apoptosis, cell cycle, and hormone ER pathway were represented the crucial regulation pathways by both E2F8 and MYBL2. In the meantime, database analysis indicated that high expression of E2F8 responded to chemotherapy, while those patients of high expression of MYBL2 responded to endocrinotherapy, and a positive correlation between the expression of E2F8 and PD-L1/CTLA4. Our cell line experiments confirmed the importance of E2F8 and MYBL2 in proliferation and chemotherapy sensitivity, possibly, the relationship with PD-L1. Additionally, we also observed that the up-regulation of E2F8 was accompanied with higher enrichments of CD4+ T cells and CD8+ T cells in breast cancers.

Conclusion

Taken together, our findings elucidated a prospective target in Basal-like breast cancer, providing underlying molecular biomarkers for the development of breast cancer treatment.

UBE2J1 inhibits colorectal cancer progression by promoting ubiquitination and degradation of RPS3

Ubiquitin-conjugating enzyme E2 J1 (UBE2J1) has been proven to participate in the ubiquitination of multiple substrate proteins. However, the underlying mechanisms of UBE2J1 as a ubiquitin-conjugating enzyme participating in cancer development and progression remain largely unknown. Here, we identified that UBE2J1 is downregulated in colorectal cancer (CRC) tissues and cell lines which are mediated by DNA hypermethylation of its promoter, and decreased UBE2J1 is associated with poor prognosis. Functionally, UBE2J1 serving as a suppressor gene inhibits the proliferation and metastasis of CRC cells. Mechanistically, UBE2J1-TRIM25, forming an E2-E3 complex, physically interacts with and targets RPS3 for ubiquitination and degradation at the K214 residue. The downregulated RPS3 caused by UBE2J1 overexpression restrains NF-κB translocation into the nucleus and therefore inactivates the NF-κB signaling pathway. Our study revealed a novel role of UBE2J1-mediated RPS3 poly-ubiquitination and degradation in disrupting the NF-κB signaling pathway, which may serve as a novel and promising biomarker and therapeutic target for CRC.

Mitochondrion-Targeted NIR Therapeutic Agent Suppresses Melanoma by Inducing Apoptosis and Cell Cycle Arrest via E2F/Cyclin/CDK Pathway

Malignant melanoma is the most fatal form of skin cancer worldwide, and earlier diagnosis and more effective therapies are required to improve prognosis. As a possible solution, near-infrared fluorescent heptamethine cyanine dyes have been shown to be useful for tumor diagnosis and treatment. Here, we synthesized a novel theranostic agent, IR-817, a multifunctional bioactive small-molecule that has near-infrared emission, targets mitochondria in cancer cells, and has selective anti-cancer effects. In in vitro experiments, IR-817 preferentially accumulated in melanoma cells through organic anion transporting polypeptide transporters but also selectively inhibited the growth of tumor cells by inducing mitochondrial-dependent intrinsic apoptosis. Mechanistically, IR-817 caused G0/G1 cell cycle arrest by targeting the E2F/Cyclin/CDK pathway. Finally, IR-817 significantly suppressed the growth of xenograft tumors in zebrafish and mice. Immunohistochemical staining and hematoxylin and eosin staining revealed that IR-817 induced apoptosis and inhibited tumor cell proliferation without notable side effects. Therefore, mitochondrial-targeting theranostic agent IR-817 may be promising for accurate tumor diagnosis, real-time monitoring, and safe anti-cancer treatments.

Relationship between miRNA and ferroptosis in tumors

Malignant tumor is a major killer that seriously endangers human health. At present, the methods of treating tumors include surgical resection, chemotherapy, radiotherapy and immunotherapy. However, the survival rate of patients is still very low due to the complicated mechanism of tumor occurrence and development and high recurrence rate. Individualized treatment will be the main direction of tumor treatment in the future. Because only by understanding the molecular mechanism of tumor development and differentially expressed genes can we carry out accurate treatment and improve the therapeutic effect. MicroRNA (miRNA) is a kind of small non coding RNA, which regulates gene expression at mRNA level and plays a key role in tumor regulation. Ferroptosis is a kind of programmed death caused by iron dependent lipid peroxidation, which is different from apoptosis, necrosis and other cell death modes. Now it has been found that ferroptosis plays an important role in the occurrence and development of tumors and drug resistance. More and more studies have found that miRNAs can regulate tumor development and drug resistance through ferroptosis. Therefore, in this review, the mechanism of ferroptosis is briefly outlined, and the relationship between miRNAs and ferroptosis in tumors is reviewed.

Recent advances in the diagnostic and therapeutic roles of microRNAs in colorectal cancer progression and metastasis

Colorectal cancer (CRC) is the third most common malignancy in the world and one of the leading causes of cancer death; its incidence is still increasing in most countries. The early diagnostic accuracy of CRC is low, and the metastasis rate is high, resulting in a low survival rate of advanced patients. MicroRNAs (miRNAs) are a small class of noncoding RNAs that can inhibit mRNA translation and trigger mRNA degradation, and can affect a variety of cellular and molecular targets. Numerous studies have shown that miRNAs are related to tumour progression, immune system activity, anticancer drug resistance, and the tumour microenvironment. Dysregulation of miRNAs occurs in a variety of malignancies, including CRC. In this review, we summarize the recent research progress of miRNAs, their roles in tumour progression and metastasis, and their clinical value as potential biomarkers or therapeutic targets for CRC. Furthermore, we combined the roles of miRNAs in tumorigenesis and development with the therapeutic strategies of CRC patients, which will provide new ideas for the diagnosis and treatment of CRC.

MicroRNA-668-3p regulates oxidative stress and cell damage induced by Aβ1-42 by targeting the OXR1/p53-p21 axis

Background

Alzheimer’s disease (AD) is the most common type of dementia in old age and has become a serious social and medical problem threatening human health. We aimed to explore the mechanisms underlying AD development by screening for microRNAs (miRNAs) that affect AD progression and examining their role in AD development.

Methods

Hematoxylin-eosin (HE) staining, immunohistochemistry, and immunofluorescence (IF) were used to analyze the characteristics of the hippocampus, neuron cell separation, and related protein expression in mice. We used Gene Expression Omnibus (GEO) data analysis to screen miRNAs and mRNAs that affect AD progression, and quantitative reverse transcription polymerase chain reaction (RT-qPCR) and western blot analysis to determine changes in miRNA and mRNA levels before and after amyloid β (Aβ)1-42 induction. In addition, we used luciferase analysis to examine miRNA and mRNA binding and the effect of miRNA/mRNA interaction on neuronal cell proliferation. Apoptosis and reactive oxygen species (ROS) levels were examined using Cell Counting Kit-8 analysis and flow cytometry (FCM), respectively. The enzyme-linked immunosorbent assay was used to analyze changes in neuronal cell-secreted oxidative stress-related protein levels through miRNA/mRNA interaction.

Results

Oxidative stress levels were significantly increased in the AD mouse model. GEO data analysis revealed 67 dysregulated miRNAs, and miR-668-3p was identified as a potential therapeutic target for AD. We found that the AD and Aβ1-42-induced models showed an increase in miR-668-3p and a decrease in oxidation resistance 1 (OXR1) expression. The luciferase analysis results revealed that miR-668-3p may play a role in AD development by targeting OXR1 and promoting intracellular oxidative stress by activating p53-p21 signaling. The final rescue experiment also confirmed that Aβ1-42-induction decreased cell proliferation, increased apoptosis, increased cell cycle arrest, and promoted oxidative stress. Tenovin-1 (TEN) enhanced the effect of Aβ1-42, and the miR-668-3p inhibitor partially alleviated it, although the effect of the miR-668-3p inhibitor was weakened by TEN.

Conclusions

MiR-668-3p negatively regulated OXR1 expression by targeting OXR1, affecting p53-p21 protein signaling, and regulating cell damage and oxidative stress induced by Aβ1-42. Therefore, miR-668-3p may be a potential therapeutic target for AD.

Let-7i-3p inhibits the cell cycle, proliferation, invasion, and migration of colorectal cancer cells via downregulating CCND1

Dysregulated microRNAs are closely related to the malignant progression of colorectal cancer (CRC). Although abnormal let-7i-3p expression has been reported in various human cancers, its biological role and potential mechanism in CRC remain unclear. Therefore, the purpose of this study was to investigate the expression and regulation of let-7i-3p in CRC. Here, we demonstrated that let-7i-3p expression was significantly downregulated in three CRC cell lines while CyclinD1 (CCND1) was upregulated compared with the normal colon epithelial FHC cells. Moreover, bioinformatics and luciferase reporter assays revealed that CCND1 was a direct functional target of let-7i-3p. In addition, let-7i-3p overexpression or CCND1 silencing inhibited cell cycle, proliferation, invasion, and migration and diminished the activation of p-ERK in HCT116 cells. However, exogenously expressing CCND1 alleviated these effects. Taken together, our findings may provide new insight into the pathogenesis of CRC and let-7i-3p/CCND1 might function as new therapeutic targets for CRC.

MicroRNA-4463 facilitates the development of colon cancer by suppression of the expression of PPP1R12B

PURPOSE

In the present work, we investigated the expression pattern of miR-4463 in the non-metastasis and metastasis colorectal cancer (CRC) patients and its regulation axis.

METHODS

RT-qPCR assay was performed to assess miR-4463 expression in the serum and tissues of patients with non-metastasis and metastasis, and in the CRC cell lines. MTT assay, colony formation assay, transwell assay, and flow cytometry assay were used to examine the role of miR-4463 in CRC cell viability, proliferation, and migration. Bioinformatic analysis was used to identify the potential target gene of miR-4463, and the targeting relationship between miR-4463 and PPP1R12B was verified in vitro using dual luciferase assay. Western blotting assay was used to determine the protein level of the target gene PPP1R12B in CRC cells under the transfections of miR-4463 mimic, inhibitor and vectors overexpressing PPP1R12B.

RESULTS

miR-4463 was markedly increased in the non-metastasis CRC tissues, and increased even higher in the metastasis CRC tissues, while miR-4463 expression had no significant difference in serum from non-metastasis and metastasis CRC samples. Besides, miR-4463 was upregulated in CRC cell lines. Functionally, miR-4463 promoted CRC cell proliferation, migration, and inhibiting cell apoptosis. Further analysis revealed that the miR-4463/PPP1R12B axis was responsible for the role of this miRNA.

CONCLUSION

We reported the roles of miR-4463 in CRC proliferation and migration, supporting that miR-4463 could be a potential predictive diagnostic marker for colon cancer.

MicroRNA-1-3p affects lung adenocarcinoma progression through E2F8 and regulating NF-кB pathway

E2F8 can modulate development and progression of various cancers including cervical cancer, breast cancer and hepatocellular carcinoma. But its mechanism in lung adenocarcinoma (LUAD) remains underexplored. In this study, we conducted a series of experiments including qRT-PCR, western blot, CCK-8, scratch healing assay, Transwell, and flow cytometry. Through these assays, we confirmed the notable overexpression of E2F8 in LUAD and its promoting effects on LUAD cell proliferation, migration and invasion. Subsequently, microRNA-1-3p that was negatively associated with E2F8 expression was identified through bioinformatics analysis. qRT-PCR was then carried out for quantification of microRNA-1-3p expression, which displayed low microRNA-1-3p expression in LUAD cells. In addition, dual-luciferase reporter gene assay was utilized for validating the targeted relationship between microRNA-1-3p and E2F8. The results denoted that microRNA-1-3p could bind to the promoter region of E2F8. Finally, the results of rescue experiment revealed that microRNA-1-3p negatively modulated E2F8 level. It regulated NF-κB pathway to repress LUAD cell proliferative, migratory, and invasive properties, lead to cell cycle arrest in G0/G1 phase, and enhance cell apoptosis level. This study unraveled that microRNA-1-3p/E2F8 constrained LUAD malignant progression through NF-κB pathway, which may provide possible targets for LUAD diagnosis and treatment.

Upregulated circTMEM59 Inhibits Cell Growth and Metastasis by miR-668-3p/ID4 Axis in Colorectal Cancer

The incidence and mortality of colorectal cancer (CRC) are ranked in the top three worldwide in 2020. Abundant studies have reported that circular RNAs (circRNAs) act critical roles in the genesis and development of tumors, including CRC. Nevertheless, the roles and detailed regulation mechanisms of circRNAs that are related to the initiation and development of CRC have not been fully found and clarified. This research primarily revealed that circTMEM59 was greatly downregulated in CRC tissues and cell lines via qRT-PCR. In addition, the decreased expression of circTMEM59 was closely related to adverse clinicopathological characteristics and the shorter survival time of CRC patients. Then, a further study found that the overexpression of circTMEM59 suppressed cell growth and accelerated the cell death of CRC via a series of experiments in vitro and in vivo. Furthermore, circTMEM59 also repressed the metastatic behaviors of CRC cells. Further study revealed that circTMEM59 played the role of competing endogenous RNAs (ceRNAs) by binding to miR-668-3p to increase the expression of inhibitor of DNA binding 4 (ID4) in CRC. In summary, the results of this study clarified the antitumor effects of circTMEM59/miR-668-3p/ID4 axis in CRC progression and provided potential therapeutic targets and clinical prognostic markers for CRC.

The Role of MicroRNA in DNA Damage Response

DNA is essential for the development and function of organisms. A number of factors affect DNA integrity and cause DNA damages, such as ultraviolet light, ionizing radiation and hydrogen peroxide. DNA damages activate a series of intracellular reactions, called DNA damage response, which play a crucial role in the pathogenesis of cancers and other diseases. MiRNA is a type of evolutionarily conserved non-coding RNA and affects the expression of target genes by post-transcriptional regulation. Increasing evidences suggested that the expression of some miRNAs was changed in tumor cases. MiRNAs may participate in DNA damage response and affect genomic stability via influencing the processes of cell cycle, DNA damage repair and apoptosis, thus ultimately impact on tumorigenesis. Therefore, the role of miRNA in DNA damage response is reviewed, to provide a theoretical basis for the mechanism of miRNAs' effects on DNA damage response and for the research of new therapies for diseases.

The Roles of Non-Coding RNAs in Radiotherapy of Gastrointestinal Carcinoma

Radiotherapy (RT), or radiation therapy, has been widely used in clinical practice for the treatment of local advanced gastrointestinal carcinoma. RT causes DNA double-strand breaks leading to cell cytotoxicity and indirectly damages tumor cells by activating downstream genes. Non-coding RNA (including microRNAs, long non-coding RNAs (ncRNAs), and circular RNAs) is a type of RNA that does not encode a protein. As the field of ncRNAs increasingly expands, new complex roles have gradually emerged for ncRNAs in RT. It has been shown that ncRNAs can act as radiosensitivity regulators in gastrointestinal carcinoma by affecting DNA damage repair, cell cycle arrest, irradiation-induced apoptosis, cell autophagy, stemness, EMT, and cell pyroptosis. Here, we review the complex roles of ncRNAs in RT and gastrointestinal carcinoma. We also discuss the potential clinical significance and predictive value of ncRNAs in response to RT for guiding the individualized treatment of patients. This review can serve as a guide for the application of ncRNAs as radiosensitivity enhancers, radioresistance inducers, and predictors of response in RT of gastrointestinal carcinoma.

CircN4BP2L2 promotes colorectal cancer growth and metastasis through regulation of the miR-340-5p/CXCR4 axis

Colorectal cancer (CRC) is the third leading cause of cancer-related death worldwide. Dysregulation of circular RNAs (circRNAs) appears to be a critical factor in CRC progression. However, mechanistic studies delineating the role of circRNAs in CRC remain limited. In this study, qRT-PCR and western blot assays were used to measure the expression of genes and proteins. Migration, invasion, proliferation, and apoptosis were examined by wound-healing, transwell, CCK-8, colony formation, and flow cytometry assays, respectively. Molecular interactions were validated by a dual-luciferase report system. A xenograft animal model was established to examine in vivo tumor growth and lung metastasis. Our data indicated that circN4BP2L2 expression was increased in CRC tissues and cell lines. Notably, inhibition of circN4BP2L2 effectively inhibited proliferation, migration, and invasion of LoVo cells, and inhibited tumor growth and metastasis in vivo, whereas the forced expression of circN4BP2L2 facilitated the proliferation, migration, and invasion of HT-29 cells. Mechanistic studies revealed that circN4BP2L2 acted as a molecular sponge of miR-340-5p to competitively promote CXCR4 expression. Furthermore, inhibition of miR-340-5p reversed the anti-cancer effects of circN4BP2L2 or CXCR4 silencing. Our data indicated an oncogenic role of circN4BP2L2 in CRC via regulation of the miR-340-5p/CXCR4 axis, which may be a promising biomarker and target for CRC treatment.

MicroRNA miR-145-5p regulates cell proliferation and cell migration in colon cancer by inhibiting chemokine (C-X-C motif) ligand 1 and integrin α2

Colon cancer (CC), which has high morbidity and mortality, can be regulated by microRNAs. This study aimed to investigate the regulatory function of microRNA miR-145-5p in CC cells. Bioinformatics analysis was used to screen key genes in CC. The expression of miR-145-5p, chemokine (C-X-C motif) ligand 1 (CXCL1), and integrin α2 (ITGA2) in CC was confirmed by quantitative reverse transcription polymerase chain reaction and western blotting. After cell transfection, changes in proliferation and migration in CC cells were detected using the cell counting kit-8 (CCK-8), colony formation assay, and wound healing assay. A luciferase assay was conducted to confirm the interactome of miR-145-5p, CXCL1, and ITGA2 in CC cells. Bioinformatics analysis confirmed that CXCL1 and ITGA2 were key genes in CC. After performing several cell functional experiments, the results confirmed that upregulation of miR-145-5p attenuated proliferation and migration of CC cells. Luciferase assay and western blotting confirmed that CXCL1 and ITGA2 were targets of miR-145-5p, and their expression in CC could be suppressed by miR-145-5p. In conclusion, miR-145-5p is a tumor suppressor in CC and can inhibit the expression of CXCL1 and ITGA2.

Silencing FYVE, RhoGEF, and PH domain containing 1 (FGD1) suppresses melanoma progression by inhibiting PI3K/AKT signaling pathway

Cutaneous melanoma is the leading cause of death among skin cancers despite the availability of diverse treatments. FGD1 plays an important role in multiple cancers, but how it works in cutaneous melanoma has not been illustrated. Thus, this study was intended to investigate the roles of FGD1 and its underlying mechanisms in cutaneous melanoma. Bioinformatics tools and quantitative real-time polymerase chain reaction (qRT-PCR) were used to analyze the expression of FGD1 in cutaneous melanoma. After the knockdown of FGD1 in melanoma cells, the proliferation, migration, and invasion of cells were analyzed by cell counting kit-8 (CCK8) assay, colony formation assays and transwell assays. Western blot was used to check the expression of key factors in PI3K/AKT pathway. In addition, nude mice models were used to study the role of FGD1 in melanoma development and metastasis in vivo. The data demonstrated that FGD1 was up-regulated and predicted a poor clinical outcome for cutaneous melanoma patients. Knockdown of FGD1 inhibited melanoma cell proliferation, migration, and invasion. The expressions of p-PI3K and p-AKT were significantly decreased, while the expressions of PI3K and AKT showed no marked difference in the knockdown group. Meanwhile, knockdown of FGD1 suppressed the development of melanoma in vivo. This study suggested that knockdown of FGD1 could block melanoma formation and proliferation by inhibiting PI3K/AKT signaling pathway. FGD1 might be a promising therapeutic target for melanoma.

Propranolol Suppresses Proliferation and Migration of HUVECs through Regulation of the miR-206/VEGFA Axis

Propranolol has been used in the first-line therapy of infantile hemangioma (IH) for a number of years; however, the mechanisms through which propranolol regulates IH are not yet fully understood. In the present study, microRNA (miRNA/miR) sequencing analysis was performed to identify differentially expressed miRNAs in human umbilical vascular endothelial cells (HUVECs) treated with propranolol. Cell viability and apoptosis were detected using CCK-8 assay and flow cytometry, respectively. Cell migration was assessed using wound healing, Transwell, and tube formation assays. Methylation-specific PCR was then used to investigate the promoter methylation status. The levels of oxidative stress indicators, including superoxide dismutase, glutathione, and malondialdehyde were also detected. Finally, cell cycle analysis was performed using flow cytometry and western blotting. It was observed that propranolol induced the upregulation of miR-206 in HUVECs, which was caused by demethylation of the miR-206 promoter. Moreover, propranolol significantly inhibited the proliferation of HUVECs by inducing apoptosis, while these phenomena were reversed by miR-206 antagomir. VEGFA was found to be a target gene of miR-206. In addition, propranolol notably inhibited the migration and induced G1 arrest of the HUVECs, whereas these results were eliminated by miR-206 antagomir. Collectively, the findings of the present study demonstrated that propranolol may inhibit the proliferation and migration in HUVECs via modulating the miR-206/VEGFA axis. These findings suggest a novel mechanism through which propranolol suppresses the progression of IH.

MicroRNA-934 facilitates cell proliferation, migration, invasion and angiogenesis in colorectal cancer by targeting B-cell translocation gene 2

Colorectal cancer (CRC) is a global public health issue with increasing prevalence. MicroRNA-934 (miR-934) is a kind of non-coding RNA involved in the regulation of diverse cancers. Though previous researches have revealed part of association between miR-934 and CRC, the role of miR-934 in CRC pathogenesis has not been completely explored yet. In this study, we aim to investigate the effect of miR-934 on cell proliferation, migration, invasion and angiogenesis in CRC. Accordingly, miR-934 was found to be over-expressed in SW480 and HCT116 cells, two typical CRC cell lines. Meanwhile, miR-934 knockdown significantly inhibited cell proliferation and induced cell cycle arrest in SW480 and HCT116 cells. It was further validated that miR-934 knockdown displayed an inhibitory effect on cell migration and invasion in SW480 and HCT116 cells. Additionally, miR-934 deficiency markedly decreased VEGF expression in SW480 and HCT116 cells and suppressed capability of CRC cells to promote tube formation in vascular endothelial cells, which suggests the pro-angiogenesis role of miR-934 in vitro. Dual luciferase reporter assay further showed that miR-934 directly bound to B-cell translocation gene 2 (BTG2). BTG2 knockdown reversed the inhibitory effect of miR-934 silencing on cell proliferation, migration, invasion, and angiogenesis in SW480 and HCT116 cells. In summary, this study suggests that miR-934 facilitates CRC progression by targeting BTG2, and further highlights the role of miR-934 in pathogenesis of CRC.

Systematic study on expression and prognosis of E2Fs in human colorectal cancer

BACKGROUND

E2Fs are important components of transcription factors and play key roles in occurrence or advancement of various cancers, but the expression and exact roles of each E2F in colorectal cancer (CRC) are rarely known.

METHODS

To address this issue, we investigated the roles and prognostic values of E2Fs expressions in CRC patients by searching ONCOMINE, cBioPortal, GEPIA, Matascape and UALCAN.

RESULTS

E2F1, 3-8 were upregulated at the mRNA level and E2F2 was less expressed in CRC tissues than in normal tissues. The eight E2Fs were correlated with tumor stages of CRC. Survival analysis using GEPIA revealed that high expressions of E2F3, 4 were related with short overall survival in all CRC patients. The mutation rate of E2Fs (60%) was high and genetic alteration in E2Fs was linked with longer overall survival in CRC patients. Functional analysis implied that E2Fs and their 50 nearby genes were concentrated in tumor-related pathways.

CONCLUSIONS

E2Fs may be candidate biomarkers for CRC diagnosis and E2F3, 4 are potential prognosis biomarkers of CRC. Nevertheless, our findings must be validated in the future to popularize the clinical application of E2Fs in CRC.

Comprehensive Analysis of E2F Family Members in Human Gastric Cancer

Gastric cancer (GC) is the second most common cancer and the third most frequent cause of cancer-related deaths in China. E2Fs are a family of transcription factors reported to be involved in the tumor progression of various cancer types; however, the roles of individual E2Fs are still not known exactly in tumor progression of GC. In this study, we examined the expression of E2Fs to investigate their roles in tumor progression in GC patients using multiple databases, including ONCOMINE, GEPIA2, Kaplan-Meier plotter, cBioPortal, Metascape, LinkedOmics, GeneMANIA, STRING and UCSC Xena. We also performed real-time polymerase chain reaction (RT-PCR) to validate the expression levels of individual E2Fs in several GC cell lines. Our results demonstrated that the mRNA levels of E2F1/2/3/5/8 were significantly higher both in GC tissues and cell lines. The expression levels of E2F1 and E2F4 were correlated with poor overall survival (OS), decreased post-progression survival (PPS), and decreased progression-free survival (FP) in patients with GC. However, overexpression of E2F2, E2F5, E2F7 and E2F8 is significantly associated with disease-free survival and overall survival in patients with GC. In addition, higher E2F3 and E2F6 mRNA expression was found to increase GC patients' OS and PPS. 224 of 415 patients with STAD (54%) had gene mutations that were associated with longer disease-free survival (DFS) but not OS. Cell cycle pathway was closely associated with mRNA level of more than half of E2Fs (E2F1/2/3/7/8). There were close and complicated interactions among E2F family members. Finally, our results indicated the gene expressions of E2Fs had a positive relationship with its copy numbers. Taken together, E2F1/2/3/5/8 can serve as biomarkers for GC patients with high prognostic value for OS of GC patients or therapeutic targets for GC.

Circ-GALNT16 restrains colorectal cancer progression by enhancing the SUMOylation of hnRNPK

BACKGROUND

Recent studies have investigated the role of circular RNAs (circRNAs) as significant regulatory factors in multiple cancer progression. Nevertheless, the biological functions of circRNAs and the underlying mechanisms by which they regulate colorectal cancer (CRC) progression remain unclear.

METHODS

A novel circRNA (circ-GALNT16) was identified by microarray and qRT-PCR. A series of in vitro and in vivo phenotype experiments were performed to investigate the role of circ-GALNT16 in CRC. The FISH, RNA pulldown assay, RIP assay, RNA sequencing, coimmunoprecipitation, and ChIP were performed to investigate the molecular mechanisms of circ-GALNT16 in CRC progression.

RESULTS

Circ-GALNT16 was downregulated in CRC and was negatively correlated with poor prognosis. Circ-GALNT16 suppressed the proliferation and metastatic ability of CRC cells in vitro and in vivo. Mechanistically, circ-GALNT16 could bind to the KH3 domain of heterogeneous nuclear ribonucleoprotein K (hnRNPK), which promoted the SUMOylation of hnRNPK. Additionally, circ-GALNT16 could enhance the formation of the hnRNPK-p53 complex by facilitating the SUMOylation of hnRNPK. RNA sequencing assay identified serpin family E member 1 as the target gene of circ-GALNT16 at the transcriptional level. Rescue assays revealed that circ-GALNT16 regulated the expression of Serpine1 by inhibiting the deSUMOylation of hnRNPK mediated by SUMO-specific peptidase 2 and then regulating the sequence-specific DNA binding ability of the hnRNPK-p53 transcriptional complex.

CONCLUSIONS

Circ-GALNT16 suppressed CRC progression by inhibiting Serpine1 expression through regulating the sequence-specific DNA binding ability of the SENP2-mediated hnRNPK-p53 transcriptional complex and might function as a biomarker and therapeutic target for CRC.

MiRNAs and Cancer: Key Link in Diagnosis and Therapy

Since the discovery of the first microRNA (miRNA), the exploration of miRNA biology has come to a new era in recent decades. Monumental studies have proven that miRNAs can be dysregulated in different types of cancers and the roles of miRNAs turn out to function to either tumor promoters or tumor suppressors. The interplay between miRNAs and the development of cancers has grabbed attention of miRNAs as novel tools and targets for therapeutic attempts. Moreover, the development of miRNA delivery system accelerates miRNA preclinical implications. In this review, we depict recent advances of miRNAs in cancer and discuss the potential diagnostic or therapeutic approaches of miRNAs.

Whole transcriptome-based ceRNA network analysis revealed ochratoxin A-induced compromised intestinal tight junction proteins through WNT/Ca2+ signaling pathway

Ochratoxin A (OTA) is a widespread environmental pollutant that is a threat to humans and livestock and remains a global concern to public health. It has negative effects on both humans and animals that are in a continuously exposed environment. The compromised intestinal barrier caused by OTA has aroused widespread concern. This study aimed to investigate the mechanism of OTA-induced tight junction (TJ) protein damage and the relevant components of the intestinal barrier through in vivo whole transcriptome analysis combined with in vitro functional verification. Bioinformatics analysis in OTA-treated Balb/c mice demonstrated that regulated TJ protein related mRNAs were perturbed, and activated the WNT/Ca2+ signaling pathway possibly regulated by key lncRNAs and miRNAs. Competing endogenous RNA (ceRNA) network analysis revealed that lncRNA Zeb1 regulated FZD4 binding with WNT5a to release Ca2+ by targeting miR-1258-x and reduced the expression of TJ proteins, thus damaging the function of the intestinal barrier. An in vitro experiment with Caco-2 cells verified that an increase in Ca2+ level was involved in OTA-induced decreases in the expression of TJ proteins. Taken together, these results will help to identify targets in the intestinal barrier that are compromised by OTA, and will provide the basis for preventing the associated hazard and risk.

An Update on the Potential Roles of E2F Family Members in Colorectal Cancer

Colorectal cancer (CRC) is a major health burden worldwide, and thus, optimised diagnosis and treatments are imperative. E2F transcription factors (E2Fs) are a family of transcription factors consisting of eight genes, contributing to the oncogenesis and development of CRC. Importantly, E2Fs control not only the cell cycle but also apoptosis, senescence, DNA damage response, and drug resistance by interacting with multiple signaling pathways. However, the specific functions and intricate machinery of these eight E2Fs in human CRC remain unclear in many respects. Evidence on E2Fs and CRC has been scattered on the related regulatory genes, microRNAs (miRNAs), and competing endogenous RNAs (ceRNAs). Accordingly, some drugs targeting E2Fs have been transferred from preclinical to clinical application. Herein, we have systemically reviewed the current literature on the roles of various E2Fs in CRC with the purpose of providing possible clinical implications for patient diagnosis and prognosis and future treatment strategy design, thereby furthering the understanding of the E2Fs.

DNAJC2 is reversely regulated by miR‑627‑3p, promoting the proliferation of colorectal cancer

Colorectal cancer (CRC) is one of the most common malignancies among human, which is often connected with increased incidence and mortality rate. DnaJ Heat Shock Protein Family (Hsp40) Member C2 (DNAJC2) is an epigenetic factor, which is involved in a number of cytological functions, such as transcriptional regulation and ubiquitination. A number of studies reveal that DNAJC2 is closely associated with several tumors. However, the function and mechanism of DNAJC2 in CRC remains to be elucidated. In the present study, the expression of DNAJC2 was detected in CRC tissues and adjacent normal tissues. The results indicated that DNAJC2 was increased in CRC tissues and the expression level of DNAJC2 was significantly associated with tumor size. Cell function was detected via Cell Counting Kit-8, 5-ethynyl-2′-deoxyuridine, colony formation assays and flow cytometry by upregulating or knocking down of DNAJC2. Overexpression of DNAJC2 could accelerate cell proliferation while suppression of DNAJC2 decreased cell proliferation, possibly via the regulation of cell cycle regulation in vitro. It was also found that the function of DNAJC2 was reversely regulated by miR-672-3p, causing the promoting of cell proliferation through the activation of AKT/P21 signal pathway in CRC cells. These results suggested that DNAJC2 is a tumor-regulated protein in the progression of CRC and may represent a novel target for CRC detection and therapy.

Comprehensive Analysis Reveals the Potential Regulatory Mechanism Between Ub-Proteasome System and Cell Cycle in Colorectal Cancer

The ubiquitin (Ub)–proteasome system (UPS) is an important regulatory component in colorectal cancer (CRC), and the cell cycle is also characterized to play a significant role in CRC. In this present study, we firstly identified UPS-associated differentially expressed genes and all the differentially expressed protein-coding genes in CRC through three differential analyses. UPS-associated genes were also further analyzed via survival analysis. A weighted gene co-expression network analysis (WGCNA) was used to identify the cell cycle-associated genes. We used protein–protein interaction (PPI) network to comprehensively mine the potential mechanism of the UPS–cell cycle regulatory axis. Moreover, we constructed a signature based on UPS-associated genes to predict the overall survival of CRC patients. Our research provides a novel insight view of the UPS and cell cycle system in CRC.

Competing Endogenous RNA in Colorectal Cancer: An Analysis for Colon, Rectum, and Rectosigmoid Junction

BACKGROUND

Colorectal cancer (CRC) is a heterogeneous cancer. Its treatment depends on its anatomical site and distinguishes between colon, rectum, and rectosigmoid junction cancer. This study aimed to identify diagnostic and prognostic biomarkers using networks of CRC-associated transcripts that can be built based on competing endogenous RNAs (ceRNA).

METHODS

RNA expression and clinical information data of patients with colon, rectum, and rectosigmoid junction cancer were obtained from The Cancer Genome Atlas (TCGA). The RNA expression profiles were assessed through bioinformatics analysis, and a ceRNA was constructed for each CRC site. A functional enrichment analysis was performed to assess the functional roles of the ceRNA networks in the prognosis of colon, rectum, and rectosigmoid junction cancer. Finally, to verify the ceRNA impact on prognosis, an overall survival analysis was performed.

RESULTS

The study identified various CRC site-specific prognosis biomarkers: hsa-miR-1271-5p, NRG1, hsa-miR-130a-3p, SNHG16, and hsa-miR-495-3p in the colon; E2F8 in the rectum and DMD and hsa-miR-130b-3p in the rectosigmoid junction. We also identified different biological pathways that highlight differences in CRC behavior at different anatomical sites, thus reinforcing the importance of correctly identifying the tumor site.

CONCLUSIONS

Several potential prognostic markers for colon, rectum, and rectosigmoid junction cancer were found. CeRNA networks could provide better understanding of the differences between, and common factors in, prognosis of colon, rectum, and rectosigmoid junction cancer.

WSX1 act as a tumor suppressor in hepatocellular carcinoma by downregulating neoplastic PD-L1 expression

WSX1, a receptor subunit for IL-27, is widely expressed in immune cells and closely involved in immune response, but its function in nonimmune cells remains unknown. Here we report that WSX1 is highly expressed in human hepatocytes but downregulated in hepatocellular carcinoma (HCC) cells. Using NRAS/AKT-derived spontaneous HCC mouse models, we reveal an IL-27–independent tumor-suppressive effect of WSX1 that largely relies on CD8⁺ T-cell immune surveillance via reducing neoplastic PD-L1 expression and the associated CD8⁺ T-cell exhaustion. Mechanistically, WSX1 transcriptionally downregulates an isoform of PI3K—PI3Kδ and thereby inactivates AKT, reducing AKT-induced GSK3β inhibition. Activated GSK3β then boosts PD-L1 degradation, resulting in PD-L1 reduction. Overall, we demonstrate that WSX1 is a tumor suppressor that reinforces hepatic immune surveillance by blocking the PI3Kδ/AKT/GSK3β/PD-L1 pathway. Our results may yield insights into the host homeostatic control of immune response and benefit the development of cancer immunotherapies.

The biological functions of WSX1, the alpha subunit of the interleukin-27 receptor, in non-immune cells are largely unknown. Here, the authors propose an IL-27-independent tumor suppressor role for WSX1 in hepatocytes, showing that WSX1 restricts tumor progression by down-regulating PD-L1 expression in tumour cells and maximizing T cell mediated antitumor immune responses.

miR-1258 Attenuates Tumorigenesis Through Targeting E2F1 to Inhibit PCNA and MMP2 Transcription in Glioblastoma

MicroRNAs are a group of endogenous small non-coding RNAs commonly dysregulated in tumorigenesis, including glioblastoma (GBM), the most malignant brain tumor with rapid proliferation, diffuse invasion, and therapeutic resistance. Accumulating evidence has manifested that miR-1258 exerts an inhibitory role in many human cancers. However, the expression pattern of miR-1258 and its potential function in GBM tumorigenesis remain unclear. In this study, we reported that miR-1258 expression decreased with the ascending pathological grade of glioma, which indicated an unfavorable prognosis of patients. Functional assays revealed an inhibitory effect of miR-1258 on malignant proliferation, therapeutic resistance, migration, and invasion of GBM in vitro. Moreover, xenograft models also suggested a repression effect of miR-1258 on gliomagenesis. Mechanistically, miR-1258 directly targeted E2F1 in 3’-untranslated regions and attenuated E2F1-mediated downstream gene PCNA and MMP2 transcriptions. Furthermore, restoration of E2F1 expression in GBM cells effectively rescued the tumor-suppressive effect of miR-1258. Our studies illustrated that miR-1258 functioned as a tumor suppressor in GBM by directly targeting E2F1, subsequently inhibiting PCNA and MMP2 transcriptions, which contributed to new potential targets for GBM therapy and other E2F1-driven cancers.

MicroRNA-155-5p regulates survival of human decidua stromal cells through NF-κB in recurrent miscarriage

Recurrent miscarriage (RM) occurs in approximately 1% of all couples trying to conceive. Most of the research about recurrent miscarriage mainly focuses on immunology. However, the roles of microRNAs plays (miRNAs) in RM remain elusive. Here, the function of miR-155-5p in regulating survival of human decidua stromal cells through NF-κB signaling was explored in RM. The quantitative real-time polymerase chain reaction (qRT-PCR) results showed that miR-155-5p was downregulated in both decidua tissues and serum from RM patients. While, the ELISA assay revealed that the overexpression of miR-155-5p reduced the inflammatory cytokines secretion including IL-6, IFN-γ, TNF-α and IL-10 in decidua stromal cells. The results of cell counting Kit8 (CCK-8) and immunofluorescence experiments suggested that transfection of miR-155-5p into decidua stromal cells can promote the growth and proliferation of cells. In addition, overexpression of miR-155-5p can also inhibit the apoptosis of decidua stromal cells. The western blot assay results demonstrated that the miR-155-5p exerted effect mainly through activating NF-κB signaling pathway in RM. In conclusion, the miRNA-155-5p can not only promote the growth and proliferation but also inhibit the apoptosis of decidua stromal cells depending on inhibiting NF-κB signaling pathway in recurrent miscarriage.

Molecular Classification Based on Prognostic and Cell Cycle-Associated Genes in Patients With Colon Cancer

The molecular classification of patients with colon cancer is inconclusive. The gene set enrichment analysis (GSEA) of dysregulated genes among normal and tumor tissues indicated that the cell cycle played a crucial role in colon cancer. We performed univariate Cox regression analysis to find out the prognostic-related genes, and these genes were then intersected with cell cycle-associated genes and were further recognized as prognostic and cell cycle-associated genes. Unsupervised non-negative matrix factorization (NMF) clustering was performed based on cell cycle-associated genes. Two subgroups were identified with different overall survival, clinical features, cell cycle enrichment profile, and mutation profile. Through nearest template prediction (NTP), the molecular classification could be effectively repeated in the original data set and validated in several independent data sets indicating that the classification is highly repeatable. Furthermore, we constructed two prognostic signatures in two subgroups, respectively. Our molecular classification based on cell cycle may provide novel insight into the treatment and the prognosis of colon cancer.

LncRNA MTX2-6 Suppresses Cell Proliferation by Acting as ceRNA of miR-574-5p to Accumulate SMAD4 in Esophageal Squamous Cell Carcinoma

Esophageal squamous cell carcinoma (ESCC) has been one of the key causes of cancer deaths worldwide. It has been found that long non-coding RNA (lncRNA) is related to the generation and progression of various cancers (including ESCC). However, there are still many lncRNAs related to ESCC whose functions and molecular mechanisms have not been clearly elucidated. In this study, we first reported that lncRNA MTX2-6 was significantly downregulated in ESCC tissues and cell lines. The decreased expression of MTX2-6 is closely related to larger tumor and worse prognosis of ESCC patients. Through a series of functional experiments, we detected that overexpressed MTX2-6 inhibited cell proliferation and promoted cell apoptosis of ESCC in vitro and in vivo. Further studies showed that MTX2-6 exerts as a competing endogenous RNA (ceRNA) by binding miR-574-5p and elevates the expression of SMAD4 in ESCC. In summary, our results clarify the tumor suppressor roles of MTX2-6/miR-574-5p/SMAD4 axis in the progression of ESCC and provide emerging therapeutic targets for ESCC patients.

Hypoxic colorectal cancer-derived extracellular vesicles deliver microRNA-361-3p to facilitate cell proliferation by targeting TRAF3 via the noncanonical NF-κB pathways

BACKGROUND

Hypoxic tumour microenvironment (TME) is a key regulator in cancer progression. However, the communications between hypoxic cells and other components in TME during colorectal cancer (CRC) progression via extracellular vesicles (EVs) remain unclear.

METHODS

High-throughput sequencing was employed to detect aberrantly expressed microRNAs (miRNAs) in hypoxic EVs. Quantitative real-time PCR was used to confirm and screen preliminarily candidate miRNAs. The effects of EVs derived from hypoxia (<1% O2 ) and miR-361-3p on CRC growth were assessed using CCK-8 assays, colony formation assays, EdU assays, flow cytometric assays and mouse xenograft. Then, the specific mechanisms of miR-361-3p were investigated by RNA immunoprecipitation, luciferase reporter assay, Western blot, chromatin immunoprecipitation, immunohistochemistry and rescue experiments.

RESULTS

The level of miR-361-3p expression was remarkably elevated in hypoxic EVs and can be transferred to CRC cells. Functional experiments exhibited that hypoxic EVs facilitated cell growth and suppressed cell apoptosis by transferring miR-361-3p of CRC. Hypoxia-inducible factor-1α induced the elevation of miR-361-3p levels in hypoxic EVs. Upregulated miR-361-3p in CRC inhibited cell apoptosis and facilitated cell growth by directly targeting TNF receptor-associated factor 3, which consequently activated the noncanonical NF-κB pathway. Moreover, the high expression of circulating exosomal miR-361-3p was correlated to worse prognosis of CRC patients.

CONCLUSIONS

Altogether, the abnormality of exosomal miR-361-3p derived from hypoxia acts vital roles in the regulation of CRC growth and apoptosis and can be an emerging prognostic biomarker and a therapeutic target for CRC patients.

Hypoxic tumour cell-derived exosomal miR-340-5p promotes radioresistance of oesophageal squamous cell carcinoma via KLF10

Background

Radiotherapy resistance is a major obstacle in the treatment of oesophageal squamous cell carcinoma (OSCC). Hypoxia is a critical cause of radioresistance. However, the communication between hypoxic cells and aerobic cells via exosomes during the transfer of radiation resistance remains unclear.

Methods

Exo-miR-340-5p levels were analysed by RNA-seq and qRT-PCR. We co-cultured OSCC cells with isolated normoxic and hypoxic exosomes to study their impact on radiosensitivity. We used a specific exo-miR-340-5p mimic and knock-down retrovirus to explore the role of this miRNA in the transfer of radioresistance from hypoxic to normoxic cells. Dual-luciferase reporter and RIP assays were used to verify KLF10 as a putative target of miR-340-5p. Several in vitro assays were conducted and xenograft models were established to investigate the effect of exo-miR-340-5p on OSCC radiosensitivity. The plasma exo-miR-340-5p levels in OSCC patients were analysed to study the clinical value of this parameter.

Results

Hypoxic exosomes alleviated radiation-induced apoptosis and accelerated DNA damage repair. miR-340-5p was highly expressed in hypoxic exosomes and was transferred into normoxic cells, where it induced radioresistance. Overexpression of miR-340-5p in normoxic OSCC cells mimicked the radioresistance of cells co-cultured with hypoxic exosomes. Knockdown of miR-340-5p in hypoxic exosomes reversed the radioresistance effect, indicating that exo-miR-340-5p is critical for hypoxic EV-transferred radioresistance. KLF10 was identified as the direct target of miR-340-5p. Moreover, metformin was found to increase the expression of KLF10 and enhance the radiosensitivity of OSCC. Higher levels of miR-340-5p in the plasma exosomes from OSCC patients are related to a poorer radiotherapy response and prognosis.

Conclusions

Hypoxic tumour cell-derived exosomal miR-340-5p confers radioresistance in OSCC by targeting KLF10/UVRAG, suggesting that miR-340-5p could be a potential biomarker and therapeutic target for the enhancement of radiosensitivity in OSCC. Metformin can increase KLF10 expression, which ameliorates the radioresistance induced by exo-miR-340-5p transfer. Therefore, metformin could be further investigated as a therapeutic option for the treatment of OSCC.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13046-021-01834-9.