MicroRNA miR-30a inhibits cisplatin resistance in ovarian cancer cells through autophagy

Enhancing Therapeutic Efficacy in Cancer Treatment: Integrating Nanomedicine with Autophagy Inhibition Strategies

The complicated stepwise lysosomal degradation process known as autophagy is in charge of destroying and eliminating damaged organelles and defective cytoplasmic components. This mechanism promotes metabolic adaptability and nutrition recycling. Autophagy functions as a quality control mechanism in cells that support homeostasis and redox balance under normal circumstances. However, the role of autophagy in cancer is controversial because, mostly depending on the stage of the tumor, it may either suppress or support the disease. While autophagy delays the onset of tumors and slows the dissemination of cancer in the early stages of tumorigenesis, numerous studies demonstrate that autophagy promotes the development and spread of tumors as well as the evolution and development of resistance to several anticancer drugs in advanced cancer stages. In this Review, we primarily emphasize the therapeutic role of autophagy inhibition in improving the treatment of multiple cancers and give a broad overview of how its inhibition modulates cancer responses. There have been various attempts to inhibit autophagy, including the use of autophagy inhibitor drugs, gene silencing therapy (RNA interference), and nanoparticles. In this Review, all these topics are thoroughly covered and illustrated by recent studies and field investigations.

The emerging roles of miRNA-mediated autophagy in ovarian cancer

Ovarian cancer is one of the common tumors of the female reproductive organs. It has a high mortality rate, is highly heterogeneous, and early detection and primary prevention are very complex. Autophagy is a cellular process in which cytoplasmic substrates are targeted for degradation in lysosomes through membrane structures called autophagosomes. The periodic elimination of damaged, aged, and redundant cellular molecules or organelles through the sequential translation between amino acids and proteins by two biological processes, protein synthesis, and autophagic protein degradation, helps maintain cellular homeostasis. A growing number of studies have found that autophagy plays a key regulatory role in ovarian cancer. Interestingly, microRNAs regulate gene expression at the posttranscriptional level and thus can regulate the development and progression of ovarian cancer through the regulation of autophagy in ovarian cancer. Certain miRNAs have recently emerged as important regulators of autophagy-related gene expression in cancer cells. Moreover, miRNA analysis studies have now identified a sea of aberrantly expressed miRNAs in ovarian cancer tissues that can affect autophagy in ovarian cancer cells. In addition, miRNAs in plasma and stromal cells in tumor patients can affect the expression of autophagy-related genes and can be used as biomarkers of ovarian cancer progression. This review focuses on the potential significance of miRNA-regulated autophagy in the diagnosis and treatment of ovarian cancer.

Drug resistance in ovarian cancer: from mechanism to clinical trial

Ovarian cancer is the leading cause of gynecological cancer-related death. Drug resistance is the bottleneck in ovarian cancer treatment. The increasing use of novel drugs in clinical practice poses challenges for the treatment of drug-resistant ovarian cancer. Continuing to classify drug resistance according to drug type without understanding the underlying mechanisms is unsuitable for current clinical practice. We reviewed the literature regarding various drug resistance mechanisms in ovarian cancer and found that the main resistance mechanisms are as follows: abnormalities in transmembrane transport, alterations in DNA damage repair, dysregulation of cancer-associated signaling pathways, and epigenetic modifications. DNA methylation, histone modifications and noncoding RNA activity, three key classes of epigenetic modifications, constitute pivotal mechanisms of drug resistance. One drug can have multiple resistance mechanisms. Moreover, common chemotherapies and targeted drugs may have cross (overlapping) resistance mechanisms. MicroRNAs (miRNAs) can interfere with and thus regulate the abovementioned pathways. A subclass of miRNAs, "epi-miRNAs", can modulate epigenetic regulators to impact therapeutic responses. Thus, we also reviewed the regulatory influence of miRNAs on resistance mechanisms. Moreover, we summarized recent phase I/II clinical trials of novel drugs for ovarian cancer based on the abovementioned resistance mechanisms. A multitude of new therapies are under evaluation, and the preliminary results are encouraging. This review provides new insight into the classification of drug resistance mechanisms in ovarian cancer and may facilitate in the successful treatment of resistant ovarian cancer.

SMAD4 inhibits glycolysis in ovarian cancer through PI3K/AKT/HK2 signaling pathway by activating ARHGAP10

BACKGROUND

ARHGAP10 is a tumor-suppressor gene related to ovarian cancer (OC) progression; however, its specific mechanism is unclear.

AIMS

To investigate the effect of ARHGAP10 on OC cell migration, invasion, and glycolysis.

METHODS AND RESULTS

Quantitative real-time PCR (qRT-PCR) quantified mRNA and protein expressions of AKT, p-AKT, HK2, and SMAD4 were tested by Western blot. EdU, Wound healing, and Transwell assay were utilized to evaluate OC cell proliferation, migration, and invasion. We used a Seahorse XF24 Extracellular Flux Analyzer to monitor cellular oxygen consumption rates (OCR) and extracellular acidification rates (ECAR). Chromatin immunoprecipitation (ChIP) was used to analyze the transcriptional regulation of ARHGAP10 by SMAD4. ARHGAP10 expression in OC tissues was detected by immunohistochemistry. Our results showed that ARHGAP10 expression was negatively related to lactate levels in human OC tissues. ARHGAP10 overexpression can inhibit the migration, proliferation, and invasion of OC cells, and this function can be blocked by 2-Deoxy-D-glucose. Moreover, we found that ARHGAP10 expression can be rescued with the AKT inhibitor LY294002.

CONCLUSIONS

This study revealed that the antitumor effects of ARHGAP10 in vivo and in vitro possibly suppress oncogenic glycolysis through the PI3K/AKT/HK2-regulated glycolysis metabolism pathway.

Shenmai injection ameliorates doxorubicin-induced myocardial injury by suppressing autophagy-apoptosis via miR-30a

CONTEXT

Autophagy-apoptosis is the core mechanism of doxorubicin-induced myocardial injury. miR-30a is a pivotal factor in the regulation of autophagy and apoptosis. It remains unclear whether SMI exerts cardioprotective effect by regulating autophagy and apoptosis via miR-30a.

OBJECTIVE

This study evaluates the effects of SMI on ameliorating doxorubicin-induced myocardial injury.

MATERIALS AND METHODS

The level of LDH and CK, and the expression of miR-30a was detected. mCherry-EGFP-LC3B double fluorescence was used to observe autophagy flow. Apoptosis was detected by Annexin V/PI staining. Western Blot was used to estimate the expression of autophagy related proteins and apoptosis-related proteins.

RESULTS

Compared with the control group, there were evidently decreased cell viability, elevated level of LDH and CK, down-regulated expression of miR-30a in the model group. Data from Western blot and fluorescence indicated that doxorubicin contributed to the elevated autophagy and apoptosis. Compared with the model group, there were increased cell viability, decreased level of LDH and CK, and up-regulated expression of miR-30a in the Shenmai group and the Shenmai + miR-30a inhibitor group. Meanwhile, the results manifested that there were suppressed autophagy flow accompanied by the down-regulated expression of Beclin-1, LC3-II, LC3-II/LC3-I and up-regulated expression of p62 protein, and declined apoptosis rate accompanied by the up-regulated Bcl2 expression and the down-regulated expression of Bax, Cleaved Caspase-9, Cleaved Caspase-9/Caspase-9, Cleaved Caspase-3, Cleaved Caspase-3/Caspase-3 in the Shenmai group and the Shenmai + miR-30a inhibitor group.

DISCUSSION AND CONCLUSION

Shenmai injection inhibited autophagy and apoptosis via miR-30a, thereby alleviating doxorubicin-induced myocardial injury.

Hsa_circ_0000585 promotes chemoresistance to cis-platin in epithelial cells of ovarian cancer by modulating autophagy

BACKGROUND

Chemoresistance, i.e., resistance to cisplatin (DDP), has been a major obstacle to ovarian cancer treatment. It has been found that circular RNAs (circRNAs) play vital roles in the tumorigenesis various cancers by regulating autophagy, while few studies focusing on cisplatin-resistance ovarian cancer (CROC).

METHODS

The expressions of the circRNAs were detected by qRT-PCR. Short hairpin RNA targeting circRNA was used to explore the biological functions of the circRNA. Cell viability, autophagic flux, immunofluorescence, and xenograft tumors experiments were performed to further illustrate the underlying mechanisms.

RESULTS

Hsa_circ_0000585 was increased in cisplatin-resistant SKOV3/DDP cells. Stably knocking down hsa_circRNA_0000585 expression in SKOV3/DDP cells was established by RNA interference. We found that downregulation of hsa_circ_0000585 significantly enhanced the sensitivity of DDP/SkOV3 cells to DDP. In vivo study, hsa_circRNA_0000585 knockdown significantly decreased tumor volume in nude mice. Under the measurements of western blot and cellular immunofluorescence, hsa_circ_0000585 knockdown significantly inhibited the expression of Beclin1 and P62, indicating the autophagic flux was inhibited. Administrations with autophagic inhibitor "Chloroquine (CQ)" and autophagy activator "QX77" further confirmed that hsa_circ_0000585 knockdown resulted in autophagy inhibition.

CONCLUSIONS

Overall, this study provided a new insight into the role of circRNAs in the mechanism of DDP-resistance in ovarian cancer. Hsa_circRNA_0000585 may be promising therapeutic targets for the enhancement of the sensitivity of ovarian cancer cells to cisplatin-mediated chemotherapy.

Regulatory miRNAs in cancer cell recovery from therapy exposure and its implications as a novel therapeutic strategy for preventing disease recurrence

The desired outcome of cancer therapies is the eradication of disease. This can be achieved when therapy exposure leads to therapy-induced cancer cell death as the dominant outcome. Theoretically, a permanent therapy-induced growth arrest could also contribute to a complete response, which has the potential to lead to remission. However, preclinical models have shown that therapy-induced growth arrest is not always durable, as recovering cancer cell populations can contribute to the recurrence of cancer. Significant research efforts have been expended to develop strategies focusing on the prevention of recurrence. Recovery of cells from therapy exposure can occur as a result of several cell stress adaptations. These include cytoprotective autophagy, cellular quiescence, a reversable form of senescence, and the suppression of apoptosis and necroptosis. It is well documented that microRNAs regulate the response of cancer cells to anti-cancer therapies, making targeting microRNAs therapeutically a viable strategy to sensitization and the prevention of recovery. We propose that the use of microRNA-targeting therapies in prolonged sequence, that is, a significant period after initial therapy exposure, could reduce toxicity from the standard combination strategy, and could exploit new epigenetic states essential for cancer cells to recover from therapy exposure. In a step toward supporting this strategy, we survey the available scientific literature to identify microRNAs which could be targeted in sequence to eliminate residual cancer cell populations that were arrested as a result of therapy exposure. It is our hope that by successfully identifying microRNAs which could be targeted in sequence we can prevent disease recurrence.

Resveratrol plays an anti-fibrotic and anti-autophagy role by stimulating miR-192-5p expression in urethral fibrosis

BACKGROUND

Resveratrol (RSV) exerts anti-fibrotic effects on various fibrotic diseases. Whereas the biological role of RSV on urethral fibrosis remains to be elucidated. This study aimed to determine the mechanisms by which RSV affects urethral fibrosis and autophagy.

METHODS

Sprague‒Dawley rats and primary fibroblasts were treated with transforming growth factor-β1 (TGFβ1) to generate in vivo and in vitro fibrosis models. Then, those were treated with RSV, and autophagy and fibrosis-related indicators were tested.

RESULTS

Firstly, we found that RSV reversed the upregulation of indicators related to TGFβ1-induced fibrosis (TGFβ1, α-smooth muscle actin, collagen type I, and collagen type III), autophagy (TFEB and LC3), and TGFβR1/Smad4 pathway, as well as the downregulation of p62 and miR-192-5p expression both in vivo and in vitro. Overexpression of miR-192-5p suppressed the upregulation of fibrosis-related markers expression, as well as TFEB and LC3 expression, induced by TGFβ1, while the expression trend of p62 was the opposite. Inhibiting miR-192-5p reversed the effects of RSV on the model group cells. It was also shown that RSV combined with sh-Smad4 inhibited autophagy more effectively than RSV alone.

CONCLUSION

These results suggest that RSV inhibits urinary fibrosis and autophagy via the miR-192-5p/TGFβR1/Smad4 pathway. RAV may be a potential drug for alleviating urethral fibrosis.

Rational targeting of autophagy in colorectal cancer therapy: From molecular interactions to pharmacological compounds

The abnormal progression of tumors has been a problem for treatment of cancer and therapeutic should be directed towards targeting main mechanisms involved in tumorigenesis in tumors. The genomic mutations can result in changes in biological mechanisms in human cancers. Colorectal cancer is one of the most malignant tumors of gastrointestinal tract and its treatment has been faced some difficulties due to development of resistance in tumor cells and also, their malignant behavior. Hence, new therapeutic modalities for colorectal cancer are being investigated. Autophagy is a "self-digestion" mechanism that is responsible for homeostasis preserving in cells and its aberrant activation/inhibition can lead to tumorigenesis. The current review focuses on the role of autophagy mechanism in colorectal cancer. Autophagy may be associated with increase/decrease in progression of colorectal cancer due to mutual function of this molecular mechanism. Pro-survival autophagy inhibits apoptosis to increase proliferation and survival rate of colorectal tumor cells and it is also involved in cancer metastasis maybe due to EMT induction. In contrast, pro-death autophagy decreases growth and invasion of colorectal tumor cells. The status of autophagy (upregulation and down-regulation) is a determining factor for therapy response in colorectal tumor cells. Therefore, targeting autophagy can increase sensitivity of colorectal tumor cells to chemotherapy and radiotherapy. Interestingly, nanoparticles can be employed for targeting autophagy in cancer therapy and they can both induce/suppress autophagy in tumor cells. Furthermore, autophagy modulators can be embedded in nanostructures in improving tumor suppression and providing cancer immunotherapy.

Role of autophagy and its regulation by noncoding RNAs in ovarian cancer

Autophagy is a self-digestion process by which misfolded proteins and damaged organelles in eukaryotic cells are degraded to maintain cellular homeostasis. This process is involved in the tumorigenesis, metastasis, and chemoresistance of various tumors such as ovarian cancer (OC). Noncoding RNAs (ncRNAs), mainly including microRNAs, long noncoding RNAs, and circular RNAs, have been extensively investigated in cancer research for their roles in the regulation of autophagy. Recent studies have shown that in OC cells, ncRNAs can modulate the formation of autophagosomes, which affect tumor progression and chemoresistance. An understanding of the role of autophagy in OC progression, treatment, and prognosis is important, and the identification of the regulatory roles of ncRNAs in autophagy leads to intervention strategies for OC therapy. This review summarizes the role of autophagy in OC and discusses the role of ncRNA-mediated autophagy in OC, as an understanding of these roles may contribute to the development of potential therapeutic strategies for this disease.

Identification of upregulated exosomal miRNAs between A2780 and A2780/DDP human ovarian cancer cells by high-throughput sequencing

Exosomal miRNAs are known to play important roles in ovarian cancer and chemotherapeutic resistance. However, a systematic evaluation of characteristics of exosomal miRNAs involved in cisplatin resistance in ovarian cancer remains totally unclear. Exosomes (Exo-A2780, Exo-A2780/DDP) were extracted from cisplatin-sensitive cells (A2780) and cisplatin-resistant cells (A2780/DDP). Differential exosomal miRNA expression profiles were found by high-throughput sequencing (HTS). Target genes of the exo-miRNAs were predicted by using two online databases to increase the prediction accuracy. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses were utilized to find biological relationships with chemoresistance. RT‒qPCR of three exosomal miRNAs was performed, and a protein‒protein interaction (PPI) network was established to identify the hub genes. The GDSC database was used to prove the association between hsa-miR-675-3p expression and the IC50 value. An integrated miRNA-mRNA network was constructed to predict miRNA-mRNA associations. The connection between hsa-miR-675-3p and ovarian cancer was discovered by immune microenvironment analyses. The upregulated exosomal miRNAs could regulate gene targets through signalling pathways such as the Ras, PI3K/Akt, Wnt, and ErbB pathways. GO and KEGG analyses indicated that the target genes were involved in protein binding, transcription regulator activity and DNA binding. The RT‒qPCR results were consistent with the HTS data, and the results of PPI network analysis suggested that FMR1 and CD86 were the hub genes. GDSC database analysis and construction of the integrated miRNA-mRNA network suggested that hsa-miR-675-3p was associated with drug resistance. Immune microenvironment analyses showed that hsa-miR-675-3p was crucial in ovarian cancer. The study suggested that exosomal hsa-miR-675-3p is a potential target for treating ovarian cancer and overcoming cisplatin resistance.

Non-coding RNAs: The recently accentuated molecules in the regulation of cell autophagy for ovarian cancer pathogenesis and therapeutic response

Autophagy is a self-recycling and conserved process, in which the senescent cytoplasmic components are degraded in cells and then recycled to maintain homeostatic balance. Emerging evidence has suggested the involvement of autophagy in oncogenesis and progression of various cancers, such as ovarian cancer (OC). Meanwhile, the non-coding RNAs (ncRNAs) frequently regulate the mRNA transcription and other functional signaling pathways in cell autophagy, displaying promising roles in human cancer pathogenesis and therapeutic response. This article mainly reviews the cutting-edge research advances about the interactions between ncRNAs and autophagy in OC. This review not only summarizes the underlying mechanisms of dynamic ncRNA-autophagy association in OC, but also discusses their prognostic implications and therapeutic biomarkers. The aim of this review was to provide a more in-depth knowledge framework exploring the ncRNA-autophagy crosstalk and highlight the promising treatment strategies for OC patients.

Non-coding RNA and autophagy: Finding novel ways to improve the diagnostic management of bladder cancer

Major fraction of the human genome is transcribed in to the RNA but is not translated in to any specific functional protein. These transcribed but not translated RNA molecules are called as non-coding RNA (ncRNA). There are thousands of different non-coding RNAs present inside the cells, each regulating different cellular pathway/pathways. Over the last few decades non-coding RNAs have been found to be involved in various diseases including cancer. Non-coding RNAs are reported to function both as tumor enhancer and/or tumor suppressor in almost each type of cancer. Urothelial carcinoma of the urinary bladder is the second most common urogenital malignancy in the world. Over the last few decades, non-coding RNAs were demonstrated to be linked with bladder cancer progression by modulating different signalling pathways and cellular processes such as autophagy, metastasis, drug resistance and tumor proliferation. Due to the heterogeneity of bladder cancer cells more in-depth molecular characterization is needed to identify new diagnostic and treatment options. This review emphasizes the current findings on non-coding RNAs and their relationship with various oncological processes such as autophagy, and their applicability to the pathophysiology of bladder cancer. This may offer an understanding of evolving non-coding RNA-targeted diagnostic tools and new therapeutic approaches for bladder cancer management in the future.

Non-coding RNA in cancer drug resistance: Underlying mechanisms and clinical applications

Cancer is one of the most frequently diagnosed malignant diseases worldwide, posing a serious, long-term threat to patients’ health and life. Systemic chemotherapy remains the first-line therapeutic approach for recurrent or metastatic cancer patients after surgery, with the potential to effectively extend patient survival. However, the development of drug resistance seriously limits the clinical efficiency of chemotherapy and ultimately results in treatment failure and patient death. A large number of studies have shown that non-coding RNAs (ncRNAs), particularly microRNAs, long non-coding RNAs, and circular RNAs, are widely involved in the regulation of cancer drug resistance. Their dysregulation contributes to the development of cancer drug resistance by modulating the expression of specific target genes involved in cellular apoptosis, autophagy, drug efflux, epithelial-to-mesenchymal transition (EMT), and cancer stem cells (CSCs). Moreover, some ncRNAs also possess great potential as efficient, specific biomarkers in diagnosis and prognosis as well as therapeutic targets in cancer patients. In this review, we summarize the recent findings on the emerging role and underlying mechanisms of ncRNAs involved in cancer drug resistance and focus on their clinical applications as biomarkers and therapeutic targets in cancer treatment. This information will be of great benefit to early diagnosis and prognostic assessments of cancer as well as the development of ncRNA-based therapeutic strategies for cancer patients.

Long non-coding RNA (lncRNA) H19 in human cancer: From proliferation and metastasis to therapy

Initiation and development of cancer depend on multiple factors that mutations in genes and epigenetic level can be considered as important drivers. Epigenetic factors include a large family of members and understanding their function in cancer has been a hot topic. LncRNAs are RNA molecules with no capacity in synthesis of proteins, and they have regulatory functions in cells. LncRNAs are localized in nucleus and cytoplasm, and their abnormal expression is related to development of tumor. This manuscript emphasizes on the role of lncRNA H19 in various cancers and its association with tumor hallmarks. The function of lncRNA H19 in most tumors is oncogenic and therefore, tumor cells increase its expression for promoting their progression. LncRNA H19 contributes to enhancing growth and cell cycle of cancers and by EMT induction, it is able to elevate metastasis rate. Silencing H19 induces apoptotic cell death and disrupts progression of tumors. LncRNA H19 triggers chemo- and radio-resistance in cancer cells. miRNAs are dually upregulated/down-regulated by lncRNA H19 in increasing tumor progression. Anti-cancer agents reduce lncRNA H19 in impairing tumor progression and increasing therapy sensitivity. A number of downstream targets and molecular pathways for lncRNA H19 have been detected in cancers including miRNAs, RUNX1, STAT3, β-catenin, Akt2 and FOXM1. Clinical studies have revealed potential of lncRNA H19 as biomarker and its association with poor prognosis. LncRNA H19 can be transferred to cancer cells via exosomes in enhancing their progression.

Brucea javanica Oil Emulsion Promotes Autophagy in Ovarian Cancer Cells Through the miR-8485/LAMTOR3/mTOR/ATG13 Signaling Axis

Background: Ovarian cancer is a common malignant tumor of the female reproductive tract, with the highest mortality rate. At present, no effective approaches to improve the survival rate exist. B. javanica Oil Emulsion (BJOE), an extract from B. javanica (L.) Merr. [Simaroubaceae], exhibits antitumor effects and can increase the sensitivity of radiotherapy and chemotherapy in many types of cancers. MiR-8485, a discovered miRNA, has been shown to be involved in the occurrence and development of tumors. The purpose of this study was to investigate the effect of BJOE on the regulation of mammalian rapamycin target protein (mTOR) autophagy signal pathway and related autophagy factors on ovarian cancer cells through miR-8485.

Methods: The main chemical constituents of BJOE were determined by UHPLC-MS/MS. Detection of miR-8485 expression in ovarian cancer cells treated with BJOE by quantitative reverse transcription polymerase chain reaction (qRT-PCR). CCK8 experiment and flow cytometry were used to observe the effects of BJOE and overexpression of miR-8485 on cell proliferation and apoptosis. Then, monodansylcadaverine (MDC) fluorescence staining was used to observe the changes of autophagy vesicles before and after the effect of BJOE and overexpressed miR-8485 on cancer cells. Next, the binding sites between miR8485 and mammalian rapamycin target protein activator 3 (LAMTOR3) were detected by double luciferase reporter assay. Furthermore, qRT-PCR and Western blot experiments were used to explore the changes of autophagy-related factors LAMTOR3, mTOR and autophagy-related 13 (ATG13), and microtubule associated protein 1 light chain 3 beta (LC3-Ⅱ) after BJOE and overexpression of miR-8485, in addition to autophagy inhibitor (3-MA) for rescue experiment verification.

Results: The qRT-PCR results showed that the expression of miR-8485 increased after BJOE treatment in the SKOV3 cell. The CCK8 assay and flow cytometry analysis revealed that both BJOE and miR-8485 overexpression inhibited the proliferation and promoted the apoptosis of the SKOV3 cell. MDC fluorescence staining showed that BJOE and miR-8485 overexpression led to a significant increase in autophagy vesicles in the SKOV3 cell. Double luciferase reporter assay confirmed the existence of binding sites between miR8485 and LAMTOR3. The results of qRT-PCR and Western blot showed that BJOE and overexpressed miR-8485 downregulated the expression of LAMTOR3 and mTOR and up-regulated the expression of ATG13 and LC3-Ⅱ.

Conclusion: 1) MiR-8485 may be the key factor of BJOE in promoting autophagy and apoptosis and inhibiting cell proliferation of ovarian cancer cells; 2) BJOE may play an antitumor role by regulating LAMTOR3/mTOR/ATG13 signaling axis through miR-8485 to promote autophagy in ovarian cancer cells.