Micro RNA-518 inhibits gastric cancer cell growth by inducing apoptosis via targeting MDM2

Targeting MDM2 in malignancies is a promising strategy for overcoming resistance to anticancer immunotherapy

MDM2 has been established as a biomarker indicating poor prognosis for individuals undergoing immune checkpoint inhibitor (ICI) treatment for different malignancies by various pancancer studies. Specifically, patients who have MDM2 amplification are vulnerable to the development of hyperprogressive disease (HPD) following anticancer immunotherapy, resulting in marked deleterious effects on survival rates. The mechanism of MDM2 involves its role as an oncogene during the development of malignancy, and MDM2 can promote both metastasis and tumor cell proliferation, which indirectly leads to disease progression. Moreover, MDM2 is vitally involved in modifying the tumor immune microenvironment (TIME) as well as in influencing immune cells, eventually facilitating immune evasion and tolerance. Encouragingly, various MDM2 inhibitors have exhibited efficacy in relieving the TIME suppression caused by MDM2. These results demonstrate the prospects for breakthroughs in combination therapy using MDM2 inhibitors and anticancer immunotherapy.

An emphasis on the interaction of signaling pathways highlights the role of miRNAs in the etiology and treatment resistance of gastric cancer

Gastric cancer (GC) is 4th in incidence and mortality rates globally. Several genetic and epigenetic factors, including microRNAs (miRNAs), affect its initiation and progression. miRNAs are short chains of nucleic acids that can regulate several cellular processes by controlling their gene expression. So, dysregulation of miRNAs expressions is associated with GC initiation, progression, invasion capacity, apoptosis evasions, angiogenesis, promotion and EMT enhancement. Of important pathways in GC and controlled by miRNAs are Wnt/β-catenin signaling, HMGA2/mTOR/P-gp, PI3K/AKT/c-Myc, VEGFR and TGFb signaling. Hence, this review was conducted to review an updated view of the role of miRNAs in GC pathogenesis and their modulatory effects on responses to different GC treatment modalities.

STAT2 act a prognostic biomarker and associated with immune infiltration in kidney renal clear cell carcinoma

Renal clear cell carcinoma (KIRC) is a malignancy of the renal epithelial cells with poor prognosis. Notably, the JAK-STAT pathway mediates cell proliferation and immune response. Accumulating evidence suggests that STATs act as immune checkpoint inhibitors in various cancers. Nonetheless, the role of STAT2 in KIRC remains elusive. Herein, analyses were performed using a series of interactive web databases including Oncomine, GEPIA and TIMER. In sub-group analyses, STAT2 was upregulated at both the mRNA and protein levels in KIRC patients. Besides, KIRC patients with high STAT2 expression exhibited a poor overall survival. Moreover, Cox regression analysis revealed that STAT2 expression, nodal metastasis and clinical stage were independent factors affecting the prognosis of KIRC patients. There was a significant positive correlation between STAT2 expression, and the abundance of immune cells as well as the expression of immune biomarker sets. In addition, STAT2 was found to be implicated in immune response, cytokine-cytokine receptor interaction, and Toll-like receptor signaling pathways. Also, several cancer-related kinases, miRNAs, and transcription factors associated with STAT2 were identified. Conclusively, we revealed that STAT2 is a potential prognosis biomarker and associated with immune infiltration in kidney renal clear cell carcinoma. This study offers additional data that will help in further research on the roles of STAT2 protein in carcinogenesis.

Therapeutic advancements in targeting BCL-2 family proteins by epigenetic regulators, natural, and synthetic agents in cancer

Cancer is amongst the deadliest and most disruptive disorders, having a much higher death rate than other diseases worldwide. Human cancer rates continue to rise, thereby posing the most significant concerns for medical health professionals. In the last two decades, researchers have gone past several milestones in tackling cancer while gaining insight into the role of apoptosis in cancer or targeting various biomarker tools for prognosis and diagnosis. Apoptosis which is still a topic full of complexities, can be controlled considerably by B-cell lymphoma 2 (BCL-2) and its family members. Therefore, targeting proteins of this family to prevent tumorigenesis, is essential to focus on the pharmacological features of the anti-apoptotic and pro-apoptotic members, which will help to develop and manage this disorder. This review deals with the advancements of various epigenetic regulators to target BCL-2 family proteins, including the mechanism of several microRNAs (miRNAs) and long non-coding RNAs (lncRNAs). Similarly, a rise in natural and synthetic molecules' research over the last two decades has allowed us to acquire insights into understanding and managing the transcriptional alterations that have led to apoptosis and treating various neoplastic diseases. Furthermore, several inhibitors targeting anti-apoptotic proteins and inducers or activators targeting pro-apoptotic proteins in preclinical and clinical stages have been summarized. Overall, agonistic and antagonistic mechanisms of BCL-2 family proteins conciliated by epigenetic regulators, natural and synthetic agents have proven to be an excellent choice in developing cancer therapeutics.

UPS: Opportunities and challenges for gastric cancer treatment

Gastric cancer remains the fourth most frequently diagnosed malignancy and the fifth leading cause of cancer-related mortality worldwide owning to the lack of efficient drugs and targets for therapy. Accumulating evidence indicates that UPS, which consists of E1, E2, and E3 enzymes and proteasome, plays an important role in the GC tumorigenesis. The imbalance of UPS impairs the protein homeostasis network during development of GC. Therefore, modulating these enzymes and proteasome may be a promising strategy for GC target therapy. Besides, PROTAC, a strategy using UPS to degrade the target protein, is an emerging tool for drug development. Thus far, more and more PROTAC drugs enter clinical trials for cancer therapy. Here, we will analyze the abnormal expression enzymes in UPS and summarize the E3 enzymes which can be developed in PROTAC so that it can contribute to the development of UPS modulator and PROTAC technology for GC therapy.

LncRNA BBOX1-AS1 promotes pituitary adenoma progression via sponging miR-361-3p/E2F1 axis

Pituitary adenoma is one of the most common intracranial tumors, more and more studies have shown that long non-coding RNA (lncRNA) plays a very important role in pituitary adenoma. However, there are few reports on the function of lncRNA BBOX1-AS1 in pituitary adenomas, and further exploration is needed. The objective of this research is to figure out what function BBOX1-AS1 plays in pituitary adenoma and how it regulates it. The expression of the E2F1, miR-361-3p and BOX1-AS1 genes was measured using a quantitative real-time PCR method. The functional involvement of BBOX1-AS1 in pituitary adenoma was examined utilizing the Transwell assay, western blot assays and the cell counting kit-8. RNA immunoprecipitation and luciferase reporter assays revealed that miR-361-3p binds to E2F1 or BBOX1-AS1. In addition, in-vivo assays were carried out. The expression of BBOX1-AS1 in pituitary adenoma tissues and cells has been increased, according to our findings. Furthermore, it is also noted that downregulation of BBOX1-AS1causes the inhibition of pituitary adenoma cells which result in invasion, apoptosis and proliferation, as well as boosting tumor development in vivo . In addition, BBOX1-AS1 knockdown inhibited tumor development in vivo . We identify BBOX1-AS1 bind to miR-361-3p and to suppress its expression in a negative way. Moreover, miR-361-3p has been shown to bind with E2F1 and inhibit its expression. E2F1 also corrected miR-361-3p-mediated cell invasion, proliferation and apoptosis in BBOX1-AS1-dysregulated pituitary adenoma cells in rescue tests. BBOX1-AS1 increases pituitary adenoma malignant activity by sponging miR-361-3p to upregulate E2F1 expression, which may lead to a new path in pituitary adenoma therapeutic attempts.

Progression of Type 1 Diabetes: Circulating MicroRNA Expression Profiles Changes from Preclinical to Overt Disease

Objectives

To evaluate the potential biological involvement of miRNA expression in the immune response and beta cell function in T1D.

Methods

We screened 377 serum miRNAs of 110 subjects divided into four groups: healthy individuals (control group) and patients at different stages of T1D progression, from the initial immunological manifestation presenting islet autoantibodies (AbP group) until partial and strong beta cell damage in the recent (recent T1D group) and long-term T1D, with 2 to 5 years of disease (T1D 2-5y group).

Results

The results revealed 69 differentially expressed miRNAs (DEMs) in relation to controls. Several miRNAs were correlated with islet autoantibodies (IA2A, GADA, and Znt8A), age, and C-peptide levels, mainly from AbP, and recent T1D groups pointing these miRNAs as relevant to T1D pathogenesis and progression. Several miRNAs were related to metabolic derangements, inflammatory pathways, and several other autoimmune diseases. Pathway analysis of putative DEM targets revealed an enrichment in pathways related to metabolic syndrome, inflammatory response, apoptosis and insulin signaling pathways, metabolic derangements, and decreased immunomodulation. One of the miRNAs' gene targets was DYRK2 (dual-specificity tyrosine-phosphorylation-regulated kinase 2), which is an autoantigen targeted by an antibody in T1D. ROC curve analysis showed hsa-miR-16 and hsa-miR-200a-3p with AUCs greater than for glucose levels, with discriminating power for T1D prediction greater than glucose levels. Conclusions/Interpretation. Our data suggests a potential influence of DEMs on disease progression from the initial autoimmune lesion up to severe beta cell dysfunction and the role of miRNAs hsa-miR-16 and hsa-miR-200a-3p as biomarkers of T1D progression.

ROR2 increases the chemoresistance of melanoma by regulating p53 and Bcl2-family proteins via ERK hyperactivation

Background

ROR2 is a tyrosine-kinase receptor whose expression is dysregulated in many human diseases. In cancer, ROR2 stimulates proliferation, survival, migration, and metastasis, and is associated with more aggressive tumor stages. The purpose of this work is to study the role of ROR2 in the chemoresistance of melanoma.

Methods

Gain- and loss-of-function experiments were used to study the biological function of ROR2 in melanoma. Cell death induced by chemotherapeutic drugs and BH-3 mimetics was evaluated using crystal violet cytotoxicity assays and annexin V/propidium iodide staining. Western blots were used to evaluate the expression of proteins implicated in cell death. The differences observed between cells with manipulation of ROR2 levels and control cells were evaluated using both Student’s t-test and ANOVA.

Results

We describe that ROR2 contributes to tumor progression by enhancing the resistance of melanoma cells to both chemotherapeutic drugs and BH-3 mimetics. We demonstrate that ROR2 reduced cell death upon treatment with cisplatin, dacarbazine, lomustine, camptothecin, paclitaxel, ABT-737, TW-37, and venetoclax. This effect was mediated by the inhibition of apoptosis. In addition, we investigated the molecular mechanisms implicated in this role of ROR2. We identified the MDM2/p53 pathway as a novel target of ROR2 since ROR2 positively regulates MDM2 levels, thus leading to p53 downregulation. We also showed that ROR2 also upregulates Mcl-1 and Bcl2-xL while it negatively regulates Bax and Bid expression. The effect of ROR2 on the expression of these proteins is mediated by the hyperactivation of ERK.

Conclusions

These results demonstrate that ROR2 contributes to melanoma progression by inhibiting apoptosis and increasing chemoresistance. These results not only position ROR2 as a marker of chemoresistance but also support its use as a novel therapeutic target in cancer.

Supplementary Information

The online version contains supplementary material available at 10.1186/s11658-022-00327-7.

The Role of MiRNA in Cancer: Pathogenesis, Diagnosis, and Treatment

Cancer is also determined by the alterations of oncogenes and tumor suppressor genes. These gene expressions can be regulated by microRNAs (miRNA). At this point, researchers focus on addressing two main questions: "How are oncogenes and/or tumor suppressor genes regulated by miRNAs?" and "Which other mechanisms in cancer cells are regulated by miRNAs?" In this work we focus on gathering the publications answering these questions. The expression of miRNAs is affected by amplification, deletion or mutation. These processes are controlled by oncogenes and tumor suppressor genes, which regulate different mechanisms of cancer initiation and progression including cell proliferation, cell growth, apoptosis, DNA repair, invasion, angiogenesis, metastasis, drug resistance, metabolic regulation, and immune response regulation in cancer cells. In addition, profiling of miRNA is an important step in developing a new therapeutic approach for cancer.

Markedly reduced myocardial expression of γ-protocadherins and long non-coding RNAs in patients with heart disease

BACKGROUND

Adverse cardiac remodeling and tissue damage following heart disease is strongly associated with chronic low grade inflammation. The mechanisms underlying persisting inflammatory signals are not fully understood, but may involve defective and/or non-responsive transcriptional and post-transcriptional regulatory mechanisms. In the current study, we aimed to identify novel mediators and pathways involved in processes associated with inflammation in the development and maintenance of cardiac disease.

METHODS AND RESULTS

We performed RNA sequencing analysis of cardiac tissue from patients undergoing coronary artery bypass grafting (CABG) or aortic valve replacement (AVR) and compared with control tissue from multi-organ donors. Our results confirmed previous findings of a marked upregulated inflammatory state, but more importantly, we found pronounced reduction of non-protein coding genes, particularly long non-coding RNAs (lncRNA), including several lncRNAs known to be associated with inflammation and/or cardiovascular disease. In addition, Gene Set Enrichment Analysis revealed markedly downregulated microRNA pathways, resulting in aberrant expression of other genes, particularly γ-protocadherins.

CONCLUSIONS

Our data suggest that aberrant expression of non-coding gene regulators comprise crucial keys in the progression of heart disease, and may be pivotal for chronic low grade inflammation associated with cardiac dysfunction. By unmasking atypical γ-protocadherin expression as a prospective genetic biomarker of myocardial dysfunction, our study provides new insight into the complex molecular framework of heart disease. Creating new approaches to modify non-coding gene regulators, such as those identified in the current study, may define novel strategies to shift γ-protocadherin expression, thereby normalizing part of the molecular architecture associated with heart disease.

ARID1A serves as a receivable biomarker for the resistance to EGFR-TKIs in non-small cell lung cancer

ARID1A is a key component of the SWI/SNF chromatin remodeling complexes which is important for the maintaining of biological processes of cells. Recent studies had uncovered the potential role of ARID1A alterations or expression loss in the therapeutic sensitivity of cancers, but the studies in this field requires to be further summarized and discussed. Therefore, we proposed a series of mechanisms related to the resistance to EGFR-TKIs induced by ARID1A alterations or expression loss and the potential therapeutic strategies to overcome the resistance based on published studies. It suggested that ARID1A alterations or expression loss might be the regulators in PI3K/Akt, JAK/STAT and NF-κB signaling pathways which are strongly associated with the resistance to EGFR-TKIs in NSCLC patients harboring sensitive EGFR mutations. Besides, ARID1A alterations or expression loss could lead to the resistance to EGFR-TKIs via a variety of processes during the tumorigenesis and development of cancers, including epithelial to mesenchymal transition, angiogenesis and the inhibition of apoptosis. Based on the potential mechanisms related to ARID1A, we summarized that the small molecular inhibitors targeting ARID1A or PI3K/Akt pathway, the anti-angiogenic therapy and immune checkpoint inhibitors could be used for the supplementary treatment for EGFR-TKIs among NSCLC patients harboring the concomitant alterations of sensitive EGFR mutations and ARID1A.

Clinicopathological and Molecular Differences Between Gastric-type Mucinous Carcinoma and Usual-type Endocervical Adenocarcinoma of the Uterine Cervix

BACKGROUND/AIM

We investigated differences in the clinicopathological and molecular characteristics between gastric-type mucinous carcinoma (GMC) and usual-type endocervical adenocarcinoma (UEA).

PATIENTS AND METHODS

We collected the clinicopathological information and performed targeted genomic sequencing analysis.

RESULTS

GMCs exhibited significantly deeper invasion depth, larger horizontal spread, more advanced stage, more frequent distant metastasis, and more frequent parametrial and vaginal extension. Disease-free survival time of GMC patients was significantly shorter than that of UEA patients. GMCs displayed mutant p53 immunostaining pattern, whereas UEAs exhibited p16 block positivity. GMCs harbored mutations in KRAS, TP53, NF1, CDKN2A, STK11, and ARID1A. One GMC exhibited MDM2 amplification. In contrast, UEAs harbored mutations in HRAS, PIK3CA, and BRCA2. Two UEAs were found to have novel TP53 mutations.

CONCLUSION

GMC is associated with more aggressive behavior than UEA. Distinctive p53 and p16 immunostaining patterns enable differential diagnosis. GMC and UEA exhibit genetic heterogeneity with potentially actionable molecular alterations.

LncRNA LINC01503 aggravates the progression of cervical cancer through sponging miR-342-3p to mediate FXYD3 expression

Cervical cancer (CC), an aggressive malignancy, has a high risk of relapse and death, mainly occurring in females. Accumulating investigations have confirmed the critical role of long noncoding RNAs (lncRNAs) in diverse cancers. LncRNA LINC01503 has been reported as an oncogene in several cancers. Nonetheless, its role and molecular mechanism in CC have not been explored. In the present study, we found that FXYD3 expression was considerably up-regulated in CC tissues and cells. Moreover, FXYD3 deficiency conspicuously hampered cell proliferation and migration while facilitated cell apoptosis in CC cells. Subsequently, molecular mechanism experiments implied that FXYD3 was a downstream target gene of miR-342-3p, and FXYD3 expression was reversely mediated by miR-342-3p. Moreover, we discovered that LINC01503 acted as the endogenous sponge for miR-342-3p. Besides, LINC01503 negatively regulated miR-342-3p expression and positively regulated FXYD3 expression in CC. Rescue assays revealed that LINC01503 depletion-induced repression on CC progression could be partly recovered by miR-342-3p inhibition, and then the co-transfection of sh-FXYD3#1 rescued this effect. Conclusively, LINC01503 aggravated CC progression through sponging miR-342-3p to mediate FXYD3 expression, providing promising therapeutic targets for CC patients.

MiR-450a-5p Inhibits Gastric Cancer Cell Proliferation, Migration, and Invasion and Promotes Apoptosis via Targeting CREB1 and Inhibiting AKT/GSK-3β Signaling Pathway

Gastric cancer seriously affects human health and research on gastric cancer is attracting more and more attentions. In recent years, molecular targets have become the research focus. Accumulating evidence indicates that miR-450a-5p plays a critical role in cancer progression. However, the biological role of miR-450a-5p in gastric carcinogenesis remains largely unknown. In this study, we explore the effects and mechanisms of miR-450a-5p on the development and progression of gastric cancer. We used gain-of-function approaches to investigate the role of miR-450a-5p on gastric cancer cell proliferation, migration, invasion, and apoptosis using biological and molecular techniques including real-time quantitative PCR (RT-qPCR), CCK-8, colony formation, flow cytometry, Western blot, wound healing, transwell chamber, dual luciferase reporter, and tumor xenograft mouse model. We found that gastric cancer cells have low expression of miR-450a-5p and overexpression of miR-450a-5p inhibited gastric cancer cell proliferation, migration and invasion, and induced apoptosis in vitro. Moreover, we demonstrated that ectopic expression of miR-450a-5p inhibited gastric cancer growth in vivo. At the molecular level, overexpression of miR-450a-5p significantly increased the expression of pro-apoptotic proteins, including caspase-3, caspase-9, and Bax, and inhibited the expression of anti-apoptotic protein Bcl-2. Luciferase reporter experiment suggested that camp response element binding protein 1 (CREB1) had a negative correlation with miR-450a-5p expression, and knockdown of CREB1 alleviated gastric cancer growth. Furthermore, we also found that miR-450a-5p inhibited the activation of AKT/GSK-3β signaling pathway to inhibit the progression of gastric cancer. Collectively, miR-450a-5p repressed gastric cancer cell proliferation, migration and invasion and induced apoptosis through targeting CREB1 by inhibiting AKT/GSK-3β signaling pathway. MiR-450a-5p could be a novel molecular target for the treatment of gastric cancer.

Isoforms of the p53 Family and Gastric Cancer: A Ménage à Trois for an Unfinished Affair

Simple Summary

The p53 family is a complex family of transcription factors with different cellular functions that are involved in several physiological processes. A massive amount of data has been accumulated on their critical role in the tumorigenesis and the aggressiveness of cancers of different origins. If common features are observed, there are numerous specificities that may reflect particularities of the tissues from which the cancers originated. In this regard, gastric cancer tumorigenesis is rather remarkable, as it is induced by bacterial and viral infections, various chemical carcinogens, and familial genetic alterations, which provide an example of the variety of molecular mechanisms responsible for cell transformation and how they impact the p53 family. This review summarizes the knowledge gathered from over 40 years of research on the role of the p53 family in gastric cancer, which still displays one of the most elevated mortality rates amongst all types of cancers.

Abstract

Gastric cancer is one of the most aggressive cancers, with a median survival of 12 months. This illustrates its complexity and the lack of therapeutic options, such as personalized therapy, because predictive markers do not exist. Thus, gastric cancer remains mostly treated with cytotoxic chemotherapies. In addition, less than 20% of patients respond to immunotherapy. TP53 mutations are particularly frequent in gastric cancer (±50% and up to 70% in metastatic) and are considered an early event in the tumorigenic process. Alterations in the expression of other members of the p53 family, i.e., p63 and p73, have also been described. In this context, the role of the members of the p53 family and their isoforms have been investigated over the years, resulting in conflicting data. For instance, whether mutations of TP53 or the dysregulation of its homologs may represent biomarkers for aggressivity or response to therapy still remains a matter of debate. This uncertainty illustrates the lack of information on the molecular pathways involving the p53 family in gastric cancer. In this review, we summarize and discuss the most relevant molecular and clinical data on the role of the p53 family in gastric cancer and enumerate potential therapeutic innovative strategies.

Rola miRNA w rozwoju wybranych nowotworów – potencjalne zastosowanie w diagnostyce*

MikroRNA (miRNA) są małymi cząsteczkami kwasu rybonukleinowego, które mimo że nie podlegają procesowi translacji, pełnią ważną funkcję regulacyjną w komórkach eukariotycznych. Ich fizjologiczną funkcją jest utrzymywanie homeostazy komórek. Zaburzona ekspresja miRNA może spowodować rozwój wielu chorób, w tym chorób nowotworowych. Działanie miRNA polega na hamowaniu tworzenia się białek, w tym białek o właściwościach onkogennych i antyonkogennych. Mutacje w miejscach kodowania miRNA mogą prowadzić do nadmiernego lub zmniejszonego wytwarzania wspomnianych białek. Odkrycie miRNA i poznanie ich roli w komórce otworzyło nowe możliwości dla diagnostyki chorób nowotworowych. Zmiany poziomu odpowiednich miRNA, w krwiobiegu lub innych płynach ustrojowych, mogą być markerem diagnostycznym chorób. Diagnostyka onkologiczna mogłaby przebiegać na podstawie badań profilu miRNA pacjenta i porównania go z opracowanymi wcześniej profilami zmian miRNA powiązanymi z występowaniem danego rodzaju choroby nowotworowej. Informacja o zmianach profilu miRNA podstawowych w regulacji ekspresji genów związanych z procesami nowotworzenia, mogłaby się przyczynić do opracowania terapii eksperymentalnych opartych na przywróceniu pierwotnego poziomu miRNA w komórkach, a tym samym, na przywróceniu prawidłowej regulacji ekspresji genów. Coraz nowsze metody wyciszania i włączania ekspresji miRNA mogą w przyszłości zaowocować skutecznymi rozwiązaniami terapeutycznymi.

MicroRNA-518-3p suppresses cell proliferation, invasiveness, and migration in colorectal cancer via targeting TRIP4

MicroRNA (miR)-518-3p has been shown to function as a tumor suppressor. This study was conducted to investigate the effects of miR-518-3p in colorectal cancer (CRC). The miR-518-3p mimic, mimic negative control (NC), miR-518-3p inhibitor, inhibitor-NC, ShRNA-TRIP4, and ShRNA-NC vectors were transfected into SW480 cells using Lipofectamine 2000. Cell viability was detected using CCK-8. Colony formation, cell invasiveness, and cell migration were assessed by plate colony formation, Transwell assays, and wound healing assays, respectively. Relative mRNA and protein levels were detected using RT-qPCR and Western blot, respectively. The target gene thyroid hormone receptor interactor 4 (TRIP4) of miR-518-3p was identified and further verified using dual-luciferase reporter assay. Compared with normal tissues, levels of miR-518-3p were decreased and TRIP4 was significantly increased in the tissues from patients with CRC. Following transfection with a miR-518-3p mimic or ShRNA-TRIP4, cell viability decreased in a time-dependent manner, and colony formation rate, wound closure rate, and the number of invasive cells were much lower for the transfected cells than in the corresponding NC and control groups. miR-518-3p overexpression or silencing of TRIP4 significantly down-regulated the expression of MMP-2 and MMP-9. Knockdown of miR-518-3p had the opposite effects, and TRIP4 was identified as a target of miR-518-3p. The inhibitory effects of miR-518-3p on the progressions of CRC are associated with TRIP4.

OIP5-AS1 contributes to tumorigenesis in hepatocellular carcinoma by miR-300/YY1-activated WNT pathway

Background

It has reported that long non-coding RNAs (lncRNAs) exerted regulatory functions by targeting specific genes through a competing endogenous RNA (ceRNA) pathway. LncRNA OIP5-AS1 has been identified as a tumor-enhancer in several tumor types. Nonetheless, its molecular mechanism in HCC remains to be masked.

Aim of the study

This study was aimed at exploring whether and how OIP5-AS1 exert functions in HCC.

Methods

qRT-PCR and western blot were employed for detecting gene expression. CCK-8, colony formation and EdU assays were implemented to evaluate the proliferative ability of HCC cells. Caspase-3 activity and flow cytometry analyses were implemented to determine cell apoptosis and cell cycle distribution. RNA pull down, ChIP, RIP and luciferase reporter assays explored the interplays between molecules.

Results

YY1 was upregulated in HCC cells, and silenced YY1 restrained HCC cell proliferation in vitro and hampered tumor growth in vivo. Later, we discovered that miR-300 could regulate WNT pathway via targeting YY1. Furthermore, OIP5-AS1 was identified as the sponge of miR-300 and promoted cell growth in HCC. Importantly, YY1 transcriptionally activate OIP5-AS1 in turn. Rescue experiments indicated that miR-300 inhibition or YY1 overexpression abrogated the inhibitive effect of OIP5-AS1 silencing on the malignant growth of HCC cells.

Conclusions

OIP5-AS1/miR-300/YY1 feedback loop facilitates cell growth in HCC by activating WNT pathway.

Current perspectives on the dysregulated microRNAs in gastric cancer

Since gastric cancer (GC) is diagnosed at advanced stages, the survival rate is low in affected people. In this regard, investigating the mechanisms underlying GC development, are so critical. MiRNAs, which are small non coding RNAs, as a post transcriptional repressor, regulate expression of target genes by stimulating breakage or transcription suppression of their targets therefore aberrant expression of miRNAs leading to GC carcinogenesis. In the last decades, there have been various studies approving the pivotal role of miRNAs in various phases of GC development including cancer initiation, proliferation, migration, invasion, metastasis, angiogenesis, apoptosis, and drug resistance. Therefore, the present review aimed at summarizing the dysregulated miRNAs which contribute to various cellular and developmental mechanisms such as, proliferation, apoptosis, invasion, migration, and angiogenesis. Moreover, it provides an overview on novel miRNAs involved in drug resistance and circular miRNAs as cancer biomarkers. Thereafter, it is hoped that the present study will shed more light on diagnostic and prognostic biomarkers of GC, and potential GC treatments based on miRNAs.

hsa_circ_0000520 influences herceptin resistance in gastric cancer cells through PI3K-Akt signaling pathway

Background

To investigate whether hsa_circ_0000520 affects Herceptin resistance in gastric cancer by regulating the PI3K‐AKT signaling.

Methods

The expression of hsa_circ_0000520 was detected by qRT‐PCR in gastric cancer tissues and cell lines. A Herceptin‐resistant gastric cancer cell was established. PcDNA and pcDNA‐hsa_circ_0000520 were transfected into NCI‐N87R cells and treated with Herceptin at a concentration of 10 μg/mL for 24 hours. MTT tested cell proliferation, and apoptosis was measured by flow cytometry. IGF‐1 treatment was used to activate PI3K‐Akt signaling. The expression levels of related proteins were detected.

Results

The expression of hsa_circ_0000520 was reduced in gastric cancer tissues and cell lines, and hsa_circ_0000520 in NCI‐N87R cells was significantly lower than that of NCI‐N87 cells. Compared with the CON group, the cell viability of the Herceptin group was significantly reduced, the apoptosis rate was significantly increased, the level of Bax protein was significantly increased, and the levels of Bcl‐2, p‐PI3K, and p‐Akt protein were significantly reduced. Compared with the Herceptin + pcDNA group, the cell viability of the Herceptin + hsa_circ_0000520 group was significantly reduced, the apoptosis rate was significantly increased, the level of Bax protein was significantly increased, and the levels of p‐PI3K and p‐Akt proteins were significantly reduced. After IGF‐1 treatment, the cell viability was significantly increased, the apoptosis rate was significantly reduced, the level of Bax protein was significantly reduced, and the level of Bcl‐2 protein was significantly increased.

Conclusion

Hsa_circ_0000520 overexpression may reverse the Herceptin resistance of gastric cancer cells by inhibiting the PI3K‐Akt signaling pathway.

Roles of DANCR/microRNA-518a-3p/MDMA ceRNA network in the growth and malignant behaviors of colon cancer cells

Background

The competing endogenous RNA (ceRNA) networks of long non-coding RNAs (lncRNAs) and microRNAs (miRs) have aroused wide concerns. The study aims to investigate the roles of lncRNA DANCR-associated ceRNA network in the growth and behaviors of colon cancer (CC) cells.

Methods

Differentially expressed lncRNAs between CC and paracancerous tissues were analyzed using microarrays and RT-qPCR. Follow-up studies were conducted to evaluate the correlation between DANCR expression and prognosis of CC patients. Loss-of-functions of DANCR were performed to identify its role in the malignant behaviors of CC cells. Sub-cellular localization of DANCR and the potential targets of DANCR were predicted and validated. Cells with inhibited DANCR were implanted into nude mice to evaluate the tumor formation and metastasis in vivo.

Results

DANCR was highly-expressed in CC tissues and cell lines, and higher levels of DANCR were linked with worse prognosis and less survival time of CC patients. Silencing of DANCR inhibited proliferation, viability, metastasis and resistance to death of CC cells. DANCR was found to be sub-localized in cytoplasmic matrix and to mediate murine double minute 2 (MDM2) expression through sponging miR-518a-3p in CC cells, during which the Smad2/3 signaling was activated. Likewise, silencing of DANCR in CC cells inhibited tumor formation and metastasis in vivo.

Conclusion

This study provided evidence that silencing of DANCR might inhibit the growth and metastasis of CC cells through the DANCR/miR-518a-3p/MDM2 ceRNA network and the defect of Smad2/3 while activation of the p53 signaling pathways. This study may offer novel insights in CC treatment.

miR-155 inhibits oxidized low-density lipoprotein-induced apoptosis in different cell models by targeting the p85α/AKT pathway

The apoptosis of vascular endothelial cells (VECs), vascular smooth muscle cells (VSMCs), and macrophages directly causes the instability or rupture of atherosclerotic plaques. Accumulating evidence suggests that oxidized low-density lipoprotein (OxLDL) could induce apoptosis via endogenous or exogenous pathways. Interestingly, it has been reported that microRNA155 (miR-155) plays a pivotal role in the regulation of apoptosis. Here, we hypothesized that overexpression of miR-155 could inhibit OxLDL-induced apoptosis by targeting the p85α/AKT pathway. In this study, we established models of OxLDL-induced apoptosis in mouse VECs, VSMCs, and macrophages. Furthermore, we explored the effects of miR-155 expression on the apoptosis of different cells, and ultimately revealed whether miR-155 regulated apoptosis by targeting the p85α/AKT pathway. The results demonstrated that miR-155 inhibited p85α expression and attenuated VEC, VSMC, and macrophage apoptosis, at least in part by suppressing the expression of p85α-activated AKT to inhibit apoptosis. Our findings collectively suggested that miR-155 attenuated OxLDL-mediated apoptosis in different cells by targeting p85α, supporting its possible therapeutic role in atherosclerosis.

BBOX1-AS1 contributes to colorectal cancer progression by sponging hsa-miR-361-3p and targeting SH2B1

Colorectal cancer (CRC) is the third main cause of cancer‐relevant deaths worldwide, and its incidence has increased in recent decades. Previous studies have indicated that certain long noncoding RNAs (lncRNAs) have regulatory roles in tumor occurrence and progression. Often, lncRNAs are competitive endogenous RNAs that sponge microRNAs to up‐regulate mRNAs. Here, we examined the role of a novel lncRNA gamma‐butyrobetaine hydroxylase 1 antisense RNA 1 (BBOX1‐AS1) in CRC. We observed that BBOX1‐AS1 is overexpressed in CRC cell lines, and BBOX1‐AS1 knockdown enhances cell proliferation, migration and invasion while reducing cell apoptosis. miR‐361‐3p is present at a low level in CRC and is negatively modified by BBOX1‐AS1. Moreover, miR‐361‐3p was validated to be targeted by BBOX1‐AS1. Src homology 2 B adaptor protein 1 (SH2B1) was notably upregulated in CRC cell lines and was identified as a downstream gene of miR‐361‐3p. In addition, we found that miR‐361‐3p amplification can suppress the expression of SH2B1. Finally, data from rescue assays suggested that overexpression of SH2B1 counteracted BBOX1‐AS1 silencing‐mediated inhibition of CRC progression. In conclusion, BBOX1‐AS1 promotes CRC progression by sponging hsa‐miR‐361‐3p and up‐regulating SH2B1.

Combined use of murine double minute-2 promoter methylation and serum AFP improves diagnostic efficiency in hepatitis B virus-related hepatocellular carcinoma

Objective: Hepatocellular carcinoma (HCC) accounts for approximately 85% of all cases of liver cancer. In China, chronic hepatitis B virus-related HCC (HBV-related HCC) is the most common type of HCC. However, the majority of HBV-related HCC patients are asymptomatic, and the best opportunities for treating these patients are missed. The precise diagnosis of HBV-related HCC is crucial. The main purpose of this study was to evaluate the diagnostic value of murine double minute-2 (MDM2) promoter methylation in HBV-related HCC patients. Methods: The methylation status of the MDM2 promoter was detected by methylation-specific PCR. The MDM2 expression levels were validated by quantitative real-time PCR. Enzyme-linked immunosorbent assay was used to determine the levels of interleukin-6 (IL-6) and tumor-necrosis factor-α (TNF-α) in plasma. Results: The methylation frequency of the MDM2 promoter was decreased in HBV-related HCC patients. The MDM2 mRNA levels of patients with HBV-related HCC were higher than those of patients with liver cirrhosis and chronic hepatitis B. The plasma levels of IL-6 and TNF-α were significantly higher in HBV-related HCC patients than that in liver cirrhosis and chronic hepatitis B patients. The TNF-α levels were higher in the unmethylated MDM2 promoter group than in the methylated MDM2 promoter group in HBV-related HCC patients. Moreover, the combination of MDM2 promoter methylation and alpha-fetoprotein (AFP) improved the diagnosis of HBV-related HCC. Conclusions: Our study indicates, for the first time, that MDM2 promoter hypomethylation is present in HBV-related HCC patients. The combination of MDM2 promoter methylation and AFP can greatly improve diagnostic efficiency in HBV-related HCC, which might provide a new method for HBV-related HCC diagnosis.

Nuclear Factor κB Signaling and Its Related Non-coding RNAs in Cancer Therapy

Nuclear factor κB (NF-κB) acts as a nuclear factor that is composed of five main subunits. It is a pluripotent and crucial dimer transcription factor that has a close relationship with many serious illnesses, especially its influences on cell proliferation, inflammation, and cancer initiation and progression. NF-κB acts as part of the signaling pathway and determines its effect on the expression of several other genes, such as epidermal growth factor receptor (EGFR), p53, signal transducer and activator of transcription 3 (STAT3), and non-coding RNA (ncRNA). Continuous activation of the NF-κB signaling pathway has been seen in many cancer types. While the NF-κB signaling pathway is tightly regulated in physiological settings, quite frequently it is constitutively activated in cancer, and the molecular biology mechanism underlying the deregulated activation of NF-κB signaling remains unclear. In this review, we discuss the regulatory role and possible clinical significance of ncRNA (microRNA [miRNA] and long non-coding RNA [lncRNA]) in NF-κB signaling in cancer, including in the conversion of inflammation to carcinogenesis. Non-coding RNA plays an essential and complex role in the NF-κB signaling pathway. NF-κB activation can also induce the ncRNA status. Targeting NF-κB signaling by ncRNA is becoming a promising strategy of drug development and cancer treatment.

miR-1305 Inhibits The Progression Of Non-Small Cell Lung Cancer By Regulating MDM2

Background

Increasing evidence has suggested the critical implication of microRNAs (miRNAs) in the initiation and progression of non-small cell lung cancer (NSCLC). Previous studies have shown the tumor-suppressive function of miR-1305 in cancer; however, the role of miR-1305 in NSCLC has not been fully understood.

Methods

The expression of miR-1305 in NSCLC was detected by RT-qPCR. The influence of miR-1305 on the growth of NSCLC cells was determined via Cell Counting Kit 8 (CCK-8), colony formation and FACS analysis. The targets of miR-1305 were predicted with the miRDB database. Luciferase reporter assay was performed to investigate the binding between miR-1305 and 3ʹ-UTR of MDM2. Western blot was applied to check the expression of MDM2 with miR-1305.

Results

Here, we found that miR-1305 was down-regulated in NSCLC tissues and cell lines. Decreased miR-1305 was significantly correlated with the metastasis and poor prognostics of NSCLC patients. Overexpression of miR-1305 inhibited the proliferation and migration and promoted the apoptosis of NSCLC cells. Bioinformatics and luciferase assay uncovered that the mouse/murine double minute 2 (MDM2) was a target of miR-1305. miR-1305 bound the 3ʹ-untranslated region (UTR) of MDM2 and decreased the expression of MDM2 in NSCLC cells. As MDM2 was a negative regulator of p53, decreased MDM2 by miR-1305 up-regulated the abundance of p53 in NSCLC cells. Restoration of MDM2 markedly attenuated the suppressive role of miR-1305 in the proliferation and migration of NSCLC cells.

Conclusion

The findings provided novel mechanism of miR-1305/MDM2 signaling in regulating the progression of NSCLC, suggesting miR-1305 as a promising target for the treatment of NSCLC.

The role of MDM2 amplification and overexpression in therapeutic resistance of malignant tumors

The MDM2 protein encoded by the mouse double minute 2 (MDM2) gene is the primary negative regulatory factor of the p53 protein. MDM2 can ligate the p53 protein via its E3 ubiquitin ligase, and the ubiquitinated p53 can be transferred to the cytoplasm and degraded by proteasomes. Therefore, MDM2 can maintain the stability of p53 signaling pathway. MDM2 amplification has been detected in many human malignancies, including lung cancer, colon cancer and other malignancies. MDM2 overexpression is associated with chemotherapeutic resistance in human malignancies. The mechanisms of chemotherapeutic resistance by MDM2 overexpression mainly include the p53–MDM2 loop-dependent and p53–MDM2 loop-independent pathways. But the role of MDM2 overexpression in tyrosine kinase inhibitors resistance remains to be further study. This paper reviews the possible mechanisms of therapeutic resistance of malignancies induced by MDM2 amplification and overexpression, including chemotherapy, radiotherapy, targeted agents and hyperprogressive disease of immunotherapy. Besides, MDM2-targeted therapy may be a potential new strategy for treating advanced malignancies.

MicroRNAs in cancer cell death pathways: Apoptosis and necroptosis

To protect tissues and the organism from disease, potentially harmful cells are removed through programmed cell death processes, including apoptosis and necroptosis. These types of cell death are critically controlled by microRNAs (miRNAs). MiRNAs are short RNA molecules that target and inhibit expression of many cellular regulators, including those controlling programmed cell death via the intrinsic (Bcl-2 and Mcl-1), extrinsic (TRAIL and Fas), p53-and endoplasmic reticulum (ER) stress-induced apoptotic pathways, as well as the necroptosis cell death pathway. In this review, we discuss the current knowledge of apoptosis and necroptosis pathways and how these are impaired in cancer cells. We focus on how miRNAs disrupt apoptosis and necroptosis, thereby critically contributing to malignancy. Understanding which and how miRNAs and their targets affect cell death pathways could open up novel therapeutic opportunities for cancer patients. Indeed, restoration of pro-apoptotic tumor suppressor miRNAs (apoptomiRs) or inhibition of oncogenic miRNAs (oncomiRs) represent strategies that are currently being trialed or are already applied as miRNA-based cancer therapies. Therefore, better understanding the cancer type-specific expression of apoptomiRs and oncomiRs and their underlying mechanisms in cell death pathways will not only advance our knowledge, but also continue to provide new opportunities to treat cancer.

An overview of the multifaceted roles of miRNAs in gastric cancer: Spotlight on novel biomarkers and therapeutic targets

MicroRNAs (miRNAs) are a group of small non-coding RNAs that have displayed strong association with gastric cancer (GC). Through the repression of target mRNAs, miRNAs regulate many biological pathways that are involved in cell proliferation, apoptosis, migration, invasion, metastasis as well as drug resistance. The detection of miRNAs in tissues and in body fluids emerges as a promising method in the diagnosis and prognosis of GC, due to their unique expression pattern in correlation with GC. Notably, miRNAs are also identified as potential therapeutic targets for GC therapy. The present review is thus to highlight the multifaceted roles of miRNAs in GC and in GC therapies, which would give indications for future research.

Nobiletin inhibits breast cancer via p38 mitogen-activated protein kinase, nuclear transcription factor-κB, and nuclear factor erythroid 2-related factor 2 pathways in MCF-7 cells

INTRODUCTION

Breast cancer is one of the most commonly diagnosed cancers in women, with a high mortality rate.

OBJECTIVE

In the present study, we evaluated the anticancer effect of nobiletin, a flavone glycoside, on the breast cancer cell line MCF-7.

RESULT

Cell viability and proliferation decreased and cell morphology changed from diamond to round after being treated with nobiletin. Nobiletin induced apoptosis of breast cancer MCF-7 cells via regulating the protein expression of Bax, Bcl-2, cleaved caspase-3, and p53. The expression of Bcl-2 decreased, while the expression of Bax and p53 increased in MCF-7 cells treated with nobiletin. Meanwhile, nobiletin inhibited cell migration by downregulating the protein expression of matrix metalloproteinase-2 (MMP-2) and matrix metalloproteinase-9 (MMP-9). Moreover, phosphorylation of p38 was increased, and the translocation of p65 and nuclear factor erythroid 2-related factor 2 (Nrf2) to the nucleus was decreased, which suggested that the anticancer effects of nobiletin might at least partially rely on mediating the p38 mitogen-activated protein kinase, nuclear transcription factor-κB, and Nrf2 pathways in MCF-7 breast cancer cells.

CONCLUSION AND RECOMMENDATION

Our data showed that nobiletin was a potential antitumor drug, and it provided some experimental basis for the clinical application of tumor therapy.