LINC01234/MicroRNA-31-5p/MAGEA3 Axis Mediates the Proliferation and Chemoresistance of Hepatocellular Carcinoma Cells

CREB3 facilitates Donafenib resistance in hepatocellular carcinoma cells via the LSD1/CoREST/p65 axis by transcriptionally activating long noncoding RNA ZFAS1

OBJECTIVE

Drug resistance greatly limits the therapeutic effect of a drug. This study aimed to explore the role of long noncoding RNA ZFAS1 in Donafenib resistance of hepatocellular carcinoma (HCC) cells.

METHODS

The expression of CREB3, ZFAS1, and p65 in HCC cell lines was measured by RT-qPCR and western blotting. After transfection with sh-ZFAS1, sh-CREB3, or sh-CREB3 + oe-p65 in Donafenib-resistent (DR) HCC cell lines, the transfection efficiency was evaluated by RT-qPCR and western blotting. The proliferation and IC50 to Donafenib of HCC cell lines was examined by MTT assay. Cell proliferation and apoptosis were examined by colony formation and flow cytometry assays. Then, the correlation amongst CREB3, ZFAS1, LSD1/CoREST, and p65 was analysed by ChIP, dual-luciferase reporter gene, and RIP assays.

RESULTS

ZFAS1, CREB3, and p65 were upregulated in HepG2-DR and Huh7-DR cells. Silencing of ZFAS1 or CREB3 enhanced the sensitivity of HCC cells to Donafenib, inhibited cell proliferation and IC50, and increased cell apoptosis, which were reversed by p65 overexpression. Mechanistically, CREB3 bound to ZFAS1 promoter to augment ZFAS1 transcriptional expression, and ZFAS1 recruited LSD1/CoREST to the p65 promoter region to decrease H3K4 methylation and elevate p65 transcriptional expression.

CONCLUSION

CREB3 overexpression contributed to Donafenib resistance in HCC cells by activating the ZFAS1/p65 axis.

Epigenetic regulation of hepatocellular carcinoma progression: MicroRNAs as therapeutic, diagnostic and prognostic factors

Hepatocellular carcinoma (HCC), a significant challenge for public healthcare systems in developed Western countries including the USA, Canada, and the UK, is influenced by different risk factors including hepatitis virus infections, alcoholism, and smoking. The disruption in the balance of microRNAs (miRNAs) plays a vital function in tumorigenesis, given their function as regulators in numerous signaling networks. These miRNAs, which are mature and active in the cytoplasm, work by reducing the expression of target genes through their impact on mRNAs. MiRNAs are particularly significant in HCC as they regulate key aspects of the tumor, like proliferation and invasion. Additionally, during treatment phases such as chemotherapy and radiotherapy, the levels of miRNAs are key determinants. Pre-clinical experiments have demonstrated that altered miRNA expression contributes to HCC development, metastasis, drug resistance, and radio-resistance, highlighting related molecular pathways and processes like MMPs, EMT, apoptosis, and autophagy. Furthermore, the regulatory role of miRNAs in HCC extends beyond their immediate function, as they are also influenced by other epigenetic factors like lncRNAs and circular RNAs (circRNAs), as discussed in recent reviews. Applying these discoveries in predicting the prognosis of HCC could mark a significant advancement in the therapy of this disease.

DUB3 is a MAGEA3 deubiquitinase and a potential therapeutic target in hepatocellular carcinoma

Although melanoma-associated antigen A3 and A6 (MAGEA3/6)-specific tumor vaccines have shown antitumor effects in melanoma and non-small cell lung cancer (NSCLC), many cancers do not respond because MAGEA3 can promote cancer without triggering an immune response. Here, we identified DUB3 as the MAGEA3 deubiquitinase. DUB3 interacts with, deubiquitinates and stabilizes MAGEA3. Depletion of DUB3 in hepatocellular carcinoma (HCC) cells results in MAGEA3 degradation and P53-dependent growth inhibition. Moreover, DUB3 knockout attenuates HCC tumorigenesis in vivo, which can be rescued by restoration of MAGEA3. Intriguingly, pharmacological inhibition of DUB3 by palbociclib promotes degradation of MAGEA3 and inhibits tumor growth in preclinical models implanted with parental HCC cells but not with DUB3 knockout HCC cells. In patients with HCC, DUB3 is highly expressed, and its levels positively correlate with MAGEA3 levels. Taken together, DUB3 is a MAGEA3 deubiquitinase, and abrogating DUB3 enzymatic activity by palbociclib is a promising therapeutic strategy for HCC.

The interplay between noncoding RNAs and drug resistance in hepatocellular carcinoma: the big impact of little things

Hepatocellular carcinoma (HCC) is the leading cause of cancer-related death in people, and a common primary liver cancer. Lacking early diagnosis and a high recurrence rate after surgical resection, systemic treatment is still an important treatment method for advanced HCC. Different drugs have distinct curative effects, side effects and drug resistance due to different properties. At present, conventional molecular drugs for HCC have displayed some limitations, such as adverse drug reactions, insensitivity to some medicines, and drug resistance. Noncoding RNAs (ncRNAs), including microRNAs (miRNAs), long noncoding RNAs (lncRNAs) and circular RNAs (circRNAs), have been well documented to be involved in the occurrence and progression of cancer. Novel biomarkers and therapeutic targets, as well as research into the molecular basis of drug resistance, are urgently needed for the management of HCC. We review current research on ncRNAs and consolidate the known roles regulating drug resistance in HCC and examine the potential clinical applications of ncRNAs in overcoming drug resistance barriers in HCC based on targeted therapy, cell cycle non-specific chemotherapy and cell cycle specific chemotherapy.

Deciphering STAT3 signaling potential in hepatocellular carcinoma: tumorigenesis, treatment resistance, and pharmacological significance

Hepatocellular carcinoma (HCC) is considered one of the greatest challenges to human life and is the most common form of liver cancer. Treatment of HCC depends on chemotherapy, radiotherapy, surgery, and immunotherapy, all of which have their own drawbacks, and patients may develop resistance to these therapies due to the aggressive behavior of HCC cells. New and effective therapies for HCC can be developed by targeting molecular signaling pathways. The expression of signal transducer and activator of transcription 3 (STAT3) in human cancer cells changes, and during cancer progression, the expression tends to increase. After induction of STAT3 signaling by growth factors and cytokines, STAT3 is phosphorylated and translocated to the nucleus to regulate cancer progression. The concept of the current review revolves around the expression and phosphorylation status of STAT3 in HCC, and studies show that the expression of STAT3 is high during the progression of HCC. This review addresses the function of STAT3 as an oncogenic factor in HCC, as STAT3 is able to prevent apoptosis and thus promote the progression of HCC. Moreover, STAT3 regulates both survival- and death-inducing autophagy in HCC and promotes cancer metastasis by inducing the epithelial-mesenchymal transition (EMT). In addition, upregulation of STAT3 is associated with the occurrence of chemoresistance and radioresistance in HCC. Specifically, non-protein-coding transcripts regulate STAT3 signaling in HCC, and their inhibition by antitumor agents may affect tumor progression. In this review, all these topics are discussed in detail to provide further insight into the role of STAT3 in tumorigenesis, treatment resistance, and pharmacological regulation of HCC.

Identification of Cancer/Testis Antigens Related to Gastric Cancer Prognosis Based on Co-Expression Network and Integrated Transcriptome Analyses

Background

Gastric cancer is a worldwide life-threatening cancer. The underlying cause of it is still unknown. We have noticed that some cancer/testis antigens (CTAs) are up-regulated in gastric cancer. The role of these genes in gastric cancer development is not fully understood. The main aim of the current study was to comprehensively investigate CTAs' expression and function in stomach adenocarcinoma (STAD).

Materials and Methods

A comprehensive list of CTA genes was compiled from different databases. Transcriptome profiles of STAD were downloaded from the cancer genome atlas (TCGA) database and analyzed. Differentially-expressed CTAs were identified. Pathway enrichment analysis, weighted gene correlation network analysis (WGCNA), and overall survival (OS) analysis were performed on differentially-expressed CTA genes.

Results

Pathway enrichment analysis indicates that CTA genes are involved in protein binding, ribonucleic acid processing, and reproductive tissues. WGCNA showed that six differentially-expressed CTA genes, namely Melanoma antigen gene (MAGE) family member A3, A6, A12 and chondrosarcoma associated gene (CSAG) 1, 2, and 3, were correlated. Up-regulation of MAGEA11, MAGEC3, Per ARNT SIM domain containing 1 (PASD1), placenta-specific protein 1 (PLAC1) and sperm protein associated with the nucleus X-linked family member (SPANXB1) were significantly associated with lower OS of patients.

Conclusion

MAGEA11, MAGEC3, PASD1, PLAC1, and SPANXB1 can be investigated as prognostic biomarkers in basic and clinical studies. Further functional experiments are needed to understand the exact interaction mechanisms of these genes.

Pathogenesis and Current Treatment Strategies of Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is the most frequent liver cancer with high lethality and low five-year survival rates leading to a substantial worldwide burden for healthcare systems. HCC initiation and progression are favored by different etiological risk factors including hepatitis B virus (HBV) and hepatitis C virus (HCV) infection, non-/and alcoholic fatty liver disease (N/AFLD), and tobacco smoking. In molecular pathogenesis, endogenous alteration in genetics (TP53, TERT, CTNNB1, etc.), epigenetics (DNA-methylation, miRNA, lncRNA, etc.), and dysregulation of key signaling pathways (Wnt/β-catenin, JAK/STAT, etc.) strongly contribute to the development of HCC. The multitude and complexity of different pathomechanisms also reflect the difficulties in tailored medical therapy of HCC. Treatment options for HCC are strictly dependent on tumor staging and liver function, which are structured by the updated Barcelona Clinic Liver Cancer classification system. Surgical resection, local ablative techniques, and liver transplantation are valid and curative therapeutic options for early tumor stages. For multifocal and metastatic diseases, systemic therapy is recommended. While Sorafenib had been the standalone HCC first-line therapy for decades, recent developments had led to the approval of new treatment options as first-line as well as second-line treatment. Anti-PD-L1 directed combination therapies either with anti-VEGF directed agents or with anti-CTLA-4 active substances have been implemented as the new treatment standard in the first-line setting. However, data from clinical trials indicate different responses on specific therapeutic regimens depending on the underlying pathogenesis of hepatocellular cancer. Therefore, histopathological examinations have been re-emphasized by current international clinical guidelines in addition to the standardized radiological diagnosis using contrast-enhanced cross-sectional imaging. In this review, we emphasize the current knowledge on molecular pathogenesis of hepatocellular carcinoma. On this occasion, the treatment sequences for early and advanced tumor stages according to the recently updated Barcelona Clinic Liver Cancer classification system and the current algorithm of systemic therapy (first-, second-, and third-line treatment) are summarized. Furthermore, we discuss novel precautional and pre-therapeutic approaches including therapeutic vaccination, adoptive cell transfer, locoregional therapy enhancement, and non-coding RNA-based therapy as promising treatment options. These novel treatments may prolong overall survival rates in regard with quality of life and liver function as mainstay of HCC therapy.

MAGE-A3 regulates tumor stemness in gastric cancer through the PI3K/AKT pathway

Gastric cancer remains a malignant disease of the digestive tract with high mortality and morbidity worldwide. However, due to its complex pathological mechanisms and lack of effective clinical therapies, the survival rate of patients after receiving treatment is not satisfactory. A increasing number of studies have focused on cancer stem cells and their regulatory properties. In this study, we first constructed a co-expression network based on the WGCNA algorithm to identify modules with different degrees of association with tumor stemness indices. After selecting the most positively correlated modules of the stemness index, we performed a consensus clustering analysis on gastric cancer samples and constructed the co-expression network again. We then selected the modules of interest and applied univariate COX regression analysis to the genes in this module for preliminary screening. The results of the screening were then used in LASSO regression analysis to construct a risk prognostic model and subsequently a sixteen-gene model was obtained. Finally, after verifying the accuracy of the module and screening for risk genes, we identified MAGE-A3 as the final study subject. We then performed in vivo and in vitro experiments to verify its effect on tumor stemness and tumour proliferation. Our data supports that MAGE-A3 is a tumor stemness regulator and a potent prognostic biomarker which can help the prediction and treatment of gastric cancer patients.

Cancer-associated fibroblasts-derived lncRNA signature as a putative biomarker in breast cancer

Long noncoding RNAs (lncRNAs) have been reported to play a key role in regulating tumor microenvironment and immunity. Cancer-associated fibroblasts (CAFs) are abundant in many tumors. However, the functional and clinical significance of lncRNAs specifically expressed in CAFs has not been fully elucidated. In this study, we identified a list of 95 CAF-specific lncRNAs (FibLnc), including HHLA3, TP53TG1, ST7-AS1, LINC00536, ZNF503-AS1, MIR22HG, and MAPT-AS1, based on immune cell transcriptome expression profiling data. Based on the Cancer Genome Atlas and Gene Expression Omnibus datasets, we found that the FibLnc score predicted differences in overall patient survival and performed well in multiple datasets. FibLnc score was associated with the clinical stage of patients with breast cancer but did not significantly correlate with the PAM50 classification. Functional analysis showed that FibLnc was positively correlated with signaling pathways associated with malignant tumor progression. In addition, FibLnc was positively correlated with tumor mutational load and could predict immunotherapy response in patients with breast cancer receiving anti-PD-1 or anti-CTLA4 therapy. Our proposed FibLnc score was able to reflect the status of the immune environment and immunotherapeutic response in breast cancer, which could help explore potential therapeutic decisions and regulatory mechanisms of CAF-specific lncRNAs.

Hsa_circ_0000877 facilitates the progression of diffuse large B-cell lymphoma by miR-370-3p/mitogen-activated protein kinase kinase kinase kinase 4/Hippo pathway

Diffuse large B-cell lymphoma (DLBCL) originates from B lymphocytes and is a fatal hematological malignancy. Circular RNAs have been increasingly reported as a promising biological target for cancer therapy, but their role in DLBCL remains poorly studied. Relative expression levels of has_circ_0000877 (circ_0000877), microRNA-370-3p (miR-370-3p), and mitogen-activated protein kinase kinase kinase kinase 4 (MAP4K4) were assessed by quantitative real-time PCR. Western blot analysis was employed to measure protein levels. Cell Counting Kit-8 assay and 5-ethynyl-2'-deoxyuridine (EdU) assay were used to detect the proliferation of TMD8 and U2932 cells. Cell cycle and apoptosis were investigated by flow cytometry. Transwell assay was used to analyze cell migration and invasion. Molecular interaction was determined by dual-luciferase reporter assay and RNA immunoprecipitation assay. The protein expression of Ki67 in tumor tissues of mice was detected by immunohistochemistry assay. The expression of circ_0000877 was markedly elevated in DLBCL tissues and cell lines. The decreased expression of circ_0000877 significantly inhibited proliferation, migration, and invasion of DLBCL cell lines. In addition, silencing circ_0000877 promoted cell apoptosis and induced cell cycle arrest in G0/G1 phase. Then, miR-370-3p directly interacted with circ_0000877 and MAP4K4. Circ_0000877 promoted MAP4K4 level by sponging miR-370-3p. MAP4K4 depletion inhibited the activation of Hippo pathway. Finally, circ_0000877 silencing significantly prevented the growth of DLBCL cells in vivo . Our findings revealed that circ_0000877 could regulate the malignant evolution of DLBCL by miR-370-3p/MAP4K4/Hippo pathway.

Oncogenic roles of LINC01234 in various forms of human cancer

Abnormal expression of long non-coding RNAs (lncRNAs) plays an essential role in various malignant neoplasia. As a newly identified lncRNA, LINC01234 is abnormally expressed in several types of cancers and promotes the development of cancers. Accumulating evidence indicates that overexpression of LINC01234 is associated with poor clinical outcomes. Moreover, LINC01234 modulates many cellular events as a putative proto-oncogene, including proliferation, migration, invasion, apoptosis, cell cycle progression, and EMT. In terms of molecular mechanism, LINC01234 regulates gene expression by acting as ceRNA, participating in signaling pathways, interacting with proteins and other molecules, and encoding polypeptide. It reveals that LINC01234 may serve as a potential biomarker for cancer diagnosis, treatment, and prognosis. This review summarizes the expression pattern, biological function, and molecular mechanism of LINC01234 in human cancer and discusses its potential clinical utility.

IGF2BP1-regulated expression of ERRα is involved in metabolic reprogramming of chemotherapy resistant osteosarcoma cells

Doxorubicin (Dox) is the standard treatment approach for osteosarcoma (OS), while acquired drug resistance seriously attenuates its treatment efficiency. The present study aimed to investigate the potential roles of metabolic reprogramming and the related regulatory mechanism in Dox-resistant OS cells. The results showed that the ATP levels, lactate generation, glucose consumption and oxygen consumption rate were significantly increased in Dox-resistant OS cells compared with parental cells. Furthermore, the results revealed that the increased expression of estrogen-related receptor alpha (ERRα) was involved in metabolic reprogramming in chemotherapy resistant OS cells, since targeted inhibition of ERRα restored the shifting of metabolic profiles. Mechanistic analysis indicated that the mRNA stability, rather than ERRα transcription was markedly increased in chemoresistant OS cells. Therefore, it was hypothesized that the 3ʹ-untranslated region of ERRα mRNA was methylated by N⁶-methyladenine, which could further recruit insulin-like growth factor 2 mRNA binding protein 1 (IGF2BP1) to suppress mRNA decay and increase mRNA stability. IGF2BP1 knockdown downregulated ERRα and reversed the metabolic alteration of resistant OS cells. Additionally, the oncogenic effect of the IGF2BP1/ERRα axis on Dox-resistant OS cells was verified by in vitro and in vivo experiments. Clinical analysis also revealed that the expression levels of IGF2BP1 and ERRα were associated with the clinical progression of OS. Collectively, the current study suggested that the IGF2BP1/ERRα axis could regulate metabolic reprogramming to contribute to the chemoresistance of OS cells.

Oncopeptide MBOP Encoded by LINC01234 Promotes Colorectal Cancer through MAPK Signaling Pathway

Colorectal cancer (CRC) ranks third in incidence rate and second in mortality rate of malignancy worldwide, and the diagnosis and therapeutics of it remain to be further studied. With the emergence of noncoding RNAs (ncRNAs) and potential peptides derived from ncRNAs across various biological processes, we here aimed to identify a ncRNA-derived peptide possible for revealing the oncogenesis of CRC. Through combined predictive analysis of the coding potential of a batch of long noncoding RNAs (lncRNAs), the existence of an 85 amino-acid-peptide, named MEK1-binding oncopeptide (MBOP) and encoded from LINC01234 was confirmed. Mass spectrometry and Western blot assays indicated the overexpression of MBOP in CRC tissues and cell lines compared to adjacent noncancerous tissues and the normal colonic epithelial cell line. In vivo and in vitro migration and proliferation assays defined MBOP as an oncogenic peptide. Immunoprecipitation trials showed that MEK1 was the key interacting protein of MBOP, and MBOP promoted the MEK1/pERK/MMP2/MMP9 axis in CRC. Two E3-ligase enzymes MAEA and RMND5A mediated the ubiquitin-protease-system-related degradation of MBOP. This study indicates that MBOP might be a candidate prognostic indicator and a potential target for clinical therapy of CRC.

Pan-cancer analysis of the DNA methylation patterns of long non-coding RNA

Long non-coding RNA (lncRNA) regulated by abnormal DNA methylation (ADM-lncRNA) emerges as a biomarker for cancer diagnosis and treatment. This study comprehensively described the methylation patterns of lncRNA in pan-cancer using the cancer data set in The Cancer Genome Atlas (TCGA). Based on the cancer heterogeneity of ADM-lncRNA in pan-cancer, we constructed a co-expression network of pan-cancer ADM-lncRNA (pADM-lncRNA) in 10 cancers, highlighting the combined action mode of abnormal DNA methylation, and indicating the internal connection among different cancers. Functional analysis revealed the pan-carcinogenic pathway of pADM-lncRNA and suggested potential factors for cancer heterogeneity and tumor immune microenvironment changes. Survival analysis showed the potential of pADM-lncRNA-mRNA co-expression pair as cancer biomarkers. Revealing the action mode of lncRNA and DNA methylation in cancer may help understand the key molecular mechanisms of cell carcinogenesis.

LINC01234 regulates microRNA-27b-5p to induce the migration, invasion and self-renewal of ovarian cancer stem cells through targeting SIRT5

LINC01234 has been suggested to correlate with the survival of ovarian cancer (OS), but its role in the properties of OC stem cells (OCSCs) has been rarely described. We aim to investigate the effect of LINC01234 on the differentiation and self-renewal of OCSCs through adsorption of microRNA (miR)-27b-5p to target sirtuins 5 (SIRT5). Expression of LINC01234 and SIRT5 in OC and normal samples included in TCGA and GTEx was searched through the GEPIA2 database. Bioinformatics analysis was conducted to predict the relation of LINC01234, miR-27b-5p and SIRT5. Expression of LINC01234, miR-27b-5p and SIRT5 in OC tissues and cells was detected. OCSCs were cultured and identified. CD133⁺ OCSCs were introduced with related oligonucleotides or vectors of LINC01234 or miR-27b-5p and SIRT5 to figure out their roles in OCSCs progression and tumorigenesis in vivo. The interaction of miR-27b-5p with LINC01234 or SIRT5 was analyzed. Bioinformatics analysis suggested that LINC01234 was very likely to influence SIRT5 and regulate the development of OC through miR-27b-5p. Up-regulated LINC01234 exhibited in OC tissues and cells. Down-regulated LINC01234 or elevated miR-27b-5p suppressed OCSCs progression and tumorigenesis in vivo. LINC01234 could restore SIRT5 expression by binding to miR-27b-5p. Down-regulated miR-27b-5p reversed the effect of silenced LINC01234 on OCSCs development and tumorigenesis in vivo. Up-regulation of SIRT5 reduced the effects of elevated miR-27b-5p on OCSCs progression and tumorigenesis in vivo. LINC01234 regulates miR-27b-5p to induce the migration, invasion and self-renewal of OCSCs through targeting SIRT5.

Pathological stage-associated non-coding RNA long intergenic non-protein coding RNA 1234 (LINC01234) participation in cell cycle regulation in adrenocortical carcinoma through bromodomain-containing protein 4 (BRD4) expression mediation via sponging microRNA (miR)-140-3p

Many researches indicated that long non-coding RNAs (lncRNAs) were involved in the malignant progression of tumors, including Adrenocortical Carcinoma (ACC). However, as for most lncRNAs, their biological behaviors and molecular mechanism remain unclear in ACC. In the present research, weighted gene co-expression network analysis (WGCNA) was used to identify pathologically relevant gene, including lncRNAs. By comparing their expressions in GSE61359 tumors and normal controls, long intergenic non-protein coding RNA 1234 (LINC01234) was selected to investigate the clinical significance, biological function, and mechanism in ACC. Data mining revealed that LINC01234 expression was significantly up-regulated in ACC patients, and a shorter survival time presents in patients with higher LINC01234 expression compared to that in patients with lower LINC01234 expression. Further, LINC01234 silencing resulted in cells growth arrest in vitro and in vivo. Mechanism studies suggested that LINC01234 silencing induced cell cycle arrest, and bromodomain-containing protein 4 (BRD4) overexpression could restore this phenomenon. Further research showed that LINC01234 could mediate BRD4 expression through competitively sequestering microRNA (miR)-140-3p, as evidenced by the positive correlation of LINC01234 with BRD4 and inverse correlation with miR-140-3p expression. Luciferase activity assay also verified the targeting relationship between LINC01234, BRD4 and miR-140-3p. And up-regulated LINC01234 in ACC cells significantly reversed the degradation of BRD4 by miR-140-3p. Collectively, we deduce that LINC01234 functions as a ceRNA to regulate BRD4 expression by sponging miR-140-3p in ACC progress. Our findings have the potential to provide a new target for the diagnosis and treatment of ACC.

Contribution of MicroRNAs in Chemoresistance to Cisplatin in the Top Five Deadliest Cancer: An Updated Review

Cisplatin (DDP) is a well-known anticancer drug used for the treatment of numerous human cancers in solid organs, including bladder, breast, cervical, head and neck squamous cell, ovarian, among others. Its most important mode of action is the DNA-platinum adducts formation, inducing DNA damage response, silencing or activating several genes to induce apoptosis; these mechanisms result in genetics and epigenetics modifications. The ability of DDP to induce tumor cell death is often challenged by the presence of anti-apoptotic regulators, leading to chemoresistance, wherein many patients who have or will develop DDP-resistance. Cancer cells resist the apoptotic effect of chemotherapy, being a problem that severely restricts the successful results of treatment for many human cancers. In the last 30 years, researchers have discovered there are several types of RNAs, and among the most important are non-coding RNAs (ncRNAs), a class of RNAs that are not involved in protein production, but they are implicated in gene expression regulation, and representing the 98% of the human genome non-translated. Some ncRNAs of great interest are long ncRNAs, circular RNAs, and microRNAs (miRs). Accumulating studies reveal that aberrant miRs expression can affect the development of chemotherapy drug resistance, by modulating the expression of relevant target proteins. Thus, identifying molecular mechanisms underlying chemoresistance development is fundamental for setting strategies to improve the prognosis of patients with different types of cancer. Therefore, this review aimed to identify and summarize miRs that modulate chemoresistance in DDP-resistant in the top five deadliest cancer, both in vitro and in vivo human models.

An Integrative Analysis Framework for Identifying the Prognostic Markers from Multidimensional RNA Data of Clear Cell Renal Cell Carcinoma

The altered regulatory status of long noncoding RNA (lncRNA), miRNA, and mRNA and their interactions play critical roles in tumor proliferation, metastasis, and progression, which ultimately influence cancer prognosis. However, there are limited studies of comprehensive identification of prognostic biomarkers from combined data sets of the three RNA types in the highly metastatic clear cell renal cell carcinoma (ccRCC). The current study employed an integrative analysis framework of functional genomics approaches and machine learning methods to the lncRNA, miRNA, and mRNA data and identified 16 RNAs (3 lncRNAs, 6 miRNAs, and 7 mRNAs) of prognostic value, with 9 of them novel. A 16 RNA-based score was established for prognosis prediction of ccRCC with significance (P < 0.0001). The area under the curve for the score model was 0.868 to 0.870 in the training cohort and 0.714 to 0.778 in the validation cohort. Construction of the lncRNA-miRNA-mRNA interaction network showed that the downstream mRNAs and upstream lncRNAs in the network initiated from the miRNA or lncRNA markers exhibit significant enrichment in functional classifications associated with cancer metastasis, proliferation, progression, or prognosis. The functional analysis provided clear support for the role of the RNA biomarkers in predicting cancer prognosis. This study provides promising biomarkers for predicting prognosis of ccRCC using multidimensional RNA data, and these findings are expected to facilitate potential clinical applications of the biomarkers.

miR‑31‑5p‑DMD axis as a novel biomarker for predicting the development and prognosis of sporadic early‑onset colorectal cancer

The incidence of colorectal cancer (CRC) is increasing in young adults, but knowledge regarding the molecular features of sporadic early-onset colorectal cancer (SEOCRC) is limited. The objective of the present study was to investigate potential key tumorigenesis-associated genes and their regulatory microRNAs (miRNAs) in SEOCRC. Using miRNA and mRNA expression screening of SEOCRC and sporadic late-onset colorectal cancer (SLOCRC) by next generation sequencing (NGS) and bioinformatics, the SEOCRC-associated miRNAome and transcriptome were analyzed. In SEOCRC miRNA and mRNA expression profiles, the tumorigenesis-associated genes and their regulatory miRNAs were analyzed according to the miRTarBase database, and specific miRNA-mRNA pairs were selected as the candidate biomarkers in SEOCRC, which were further verified in another cohort of SEOCRC and SLOCRC patients' colon cancer and paracancerous tissues using reverse transcription-quantitative PCR and immunohistochemistry. Moreover, the clinical relevance of these paired signatures to clinicopathological features was determined in 80 patients with SEOCRC. The expression of dystrophin (DMD) was downregulated and that of miR-31-5p was upregulated in SEOCRC tissue compared with adjacent peritumoral tissue. While DMD and miR-31-5p were not differentially expressed in SLOCRC tissues compared with that in adjacent peritumoral tissues. The miR-31-5p-DMD axis was identified as the key regulatory axis specific to SEOCRC, and DMD expression was closely associated with TNM stage and lymph node metastasis. Importantly, Kaplan-Meier analysis revealed that patients with low DMD expression had significantly poorer overall survival, cancer specific survival and recurrence free survival compared with those with high expression of DMD. In conclusion, the miR-31-5p-DMD axis may serve as a novel biomarker in predicting the development of SEOCRC, and DMD can be used as a promising biomarker for the prognosis of SEOCRC.

LINC00174 Suppresses Non-Small Cell Lung Cancer Progression by Up-Regulating LATS2 via Sponging miR-31-5p

Objective

Dysregulation of long non-coding RNAs (lncRNAs) is associated with the progression of non-small cell lung cancer (NSCLC). This study aimed to investigate the role of long intergenic non-protein coding RNA 174 (LINC00174) in NSCLC.

Materials and Methods

In this experimental study, LINC00174 expression in NSCLC tissues and cell lines was investigated by reverse transcription-quantitative polymerase chain reaction (RT-qPCR). Besides, cell counting kit-8 (CCK-8), 5-bromo-2'-deoxyuridine (BrdU). Transwell and Flow Cytometry assays were applied to detect the regulatory function of LINC00174 on the growth, migration and apoptosis of NSCLC cells. Bioinformatics analysis, dual luciferase reporter gene assay and RNA immunoprecipitation (RIP) assay predicted and verified the targeting relationship between LINC00174 and miR-31-5p, and between miR-31-5p and the 3´-untranslated region (3´UTR) of large tumor suppressor kinase 2 (LATS2), respectively. Western blotting was performed to detect the regulatory function of LINC00174 and miR-31-5p on LATS2 protein expression.

Results

Compared with that in normal lung tissues, LINC00174 expression in NSCLC tissues and cell lines was reduced. LINC00174 expression was negatively associated with the TNM stage of the patients. Functional experiments showed that LINC00174 overexpression inhibited NSCLC cell multiplication and migration, and induced apoptosis. Furthermore, LINC00174 targeted miR-31-5p and repressed its expression. Additionally, LINC00174 upregulated LATS2 expression through competitively binding to miR-31-5p.

Conclusion

LINC00174, as a competitive endogenous RNA, elevates LATS2 expression by adsorbing miR-31-5p, thereby inhibiting the viability and migration of NSCLC cells, and promoting apoptosis.

Loss of miR-31-5p drives hematopoietic stem cell malignant transformation and restoration eliminates leukemia stem cells in mice

Leukemia stem cells (LSCs) propagate leukemia and are responsible for the high frequency of relapse of treated patients. The ability to target LSCs remains elusive, indicating a need to understand the underlying mechanism of LSC formation. Here, we report that miR-31-5p is reduced or undetectable in human LSCs compared to hematopoietic stem progenitor cells (HSPCs). Inhibition of miR-31-5p in HSPCs promotes the expression of its target gene FIH, encoding FIH [factor inhibiting hypoxia-inducing factor 1α (HIF-1α)], to suppress HIF-1α signaling. Increased FIH resulted in a switch from glycolysis to oxidative phosphorylation (OXPHOS) as the predominant mode of energy metabolism and increased the abundance of the oncometabolite fumarate. Increased fumarate promoted the conversion of HSPCs to LSCs and initiated myeloid leukemia-like disease in NOD-Prkdc^scid IL2rg^tm1/Bcgen (B-NDG) mice. We further demonstrated that miR-31-5p inhibited long- and short-term hematopoietic stem cells with a high frequency of LSCs. In combination with the chemotherapeutic agent Ara-C (cytosine arabinoside), restoration of miR-31-5p using G7 poly (amidoamine) nanosized dendriplex encapsulating miR-31-5p eliminated LSCs and inhibited acute myeloid leukemia (AML) progression in patient-derived xenograft mouse models. These results demonstrated a mechanism of HSC malignant transformation through altered energy metabolism and provided a potential therapeutic strategy to treat patients with AML.

The Incredible Potential of Exosomes as Biomarkers in the Diagnosis of Colorectal Cancer

Colorectal cancer (CRC) is common cancer that is one of the leading causes of cancerrelated deaths around the world. The creation of new biomarkers for this disease is an important public health strategy for lowering the disease's mortality rate. According to new research, exosomes may be important sources of biomarkers in CRC. Exosomes are nanometer-sized membrane vesicles (30-200 nm) secreted by normal and cancer cells that transport RNA and proteins between cells and are thought to help with intercellular communication. Exosomes have been linked to CRC initiation and progression, and some differentially expressed RNAs and proteins in exosomes have been identified as potential cancer detection candidates. As a result, studying the relationship between exosomes and CRC may aid in the development of new biomarkers for the disease. This article discusses the importance of exosomes as biomarkers in the diagnosis of CRC, as well as their use in the treatment of CRC metastasis, chemoresistance, and recrudescence. The benefits and drawbacks of using exosomes as tumour markers are also discussed.

HDAC1 promotes the migration of human myeloma cells via regulation of the lncRNA/Slug axis

Understanding the mechanisms underlying malignancy in myeloma cells is important for targeted treatment and drug development. Histone deacetylases (HDACs) can regulate the progression of various cancer types; however, their roles in myeloma are not well known. In the present study, the expression of class I HDACs in myeloma cells and tissues was evaluated. Furthermore, the effects of HDAC1 on the migration of myeloma cells and the associated mechanisms were investigated. Among the class I HDACs evaluated, HDAC1 was upregulated in both myeloma cells and tissues. Targeted inhibition of HDAC1 suppressed the migration of myeloma cells. Of the assessed transcription factors, small interfering (si)‑HDAC1 decreased the expression of Slug. Overexpression of Slug reversed the si‑HDAC1‑mediated suppressed migration of myeloma cells. Mechanistically, the results revealed that HDAC1 regulated the mRNA stability of Slug, while it had no effect on its transcription or nuclear export. Furthermore, HDAC1 negatively regulated the expression of long non‑coding RNA (lncRNA) NONHSAT113026, which could bind with the 3'‑untranslated region of Slug mRNA to facilitate its degradation. The present study demonstrated that HDAC1 promoted the migration of human myeloma cells via regulation of lncRNA/Slug signaling.

Long non-coding RNA LIFR-AS1 suppressed the proliferation, angiogenesis, migration and invasion of papillary thyroid cancer cells via the miR-31-5p/SIDT2 axis

Long non-coding RNA LIFR-AS1 is low-expressed in many cancers, but its functions in papillary thyroid carcinoma (PTC) were not defined and require further study. The relationship between LIFR-AS1 expression and clinicopathological characteristics of patients with PTC was statistically analyzed. The downregulation of LIFR-AS1 in PTC tissues and cell lines was predicted by bioinformatics analysis and verified by qRT-PCR. After overexpressing or silencing LIFR-AS1, the regulatory role of LIFR-AS1 in PTC was examined by performing MTT, colony formation, wound healing, Transwell, ELISA, tube formation and xenograft tumor experiment. MiR-31-5p and SID1 transmembrane family member 2 (SIDT2) expressions in PTC tissues or cell lines were detected by qRT-PCR, Western blot, or in situ hybridization. The relationship between miR-31-5p and LIFR-AS1/SIDT2 was predicted by LncBase, TargetScan or Pearson correlation test and then verified by Dual-Luciferase Reporter assay, RNA pull-down assay and qRT-PCR. The regulatory effect of LIFR-AS1/miR-31-5p/SIDT2 axis on the biological behaviors of PTC cells was confirmed by functional experiments and rescue experiments mentioned above. The tumor size and lymphatic metastasis were correlated with LIFR-AS1 overexpression. Overexpressed LIFR-AS1 suppressed tumorigenesis in vivo. LIFR-AS1 and SIDT2 expressions were suppressed in PTC tissues, while that of miR-31-5p was elevated in PTC tissues. LIFR-AS1 was negatively correlated with miR-31-5p. LIFR-AS1 sponged miR-31-5p to upregulate SIDT2, thereby inhibiting the viability, proliferation, migration, invasion, and the secretion of vascular endothelial growth factor (VEGF) of PTC cells and angiogenesis of human umbilical vein endothelial cells (HUVECs). This paper demonstrates that LIFR-AS1/miR-31-5p/SIDT2 axis modulated the development of PTC.

ln RNA LINC01234 promotes triple-negative breast cancer progression through regulating the miR-429/SYNJ1 axis

Emerging evidence has illustrated that long noncoding RNA 01234 (LINC01234) has played a pivotal role in the development and progression of human cancer. The regulatory role and underlying mechanisms of LINC01234 in triple-negative breast cancer (TNBC) remains unknown. In this study, we analyzed the expression level of LINC01234 in several breast cancer cell lines. CCK-8, EdU, flow cytometry analysis, wound healing assay, and transwell assay were carried out to investigate the effect of LINC01234 on tumor proliferation, apoptosis, and migration. Bioinformatic analysis and luciferase reporter assays were performed to confirm the molecular binding. We found that LINC01234 was dramatically upregulated in breast cancer cell lines, especially in TNBC. The loss and gain-of functional experiments revealed that LINC01234 significantly promoted proliferation, migration, and suppressed cell apoptosis of MDA-MB-231 cells in vitro and inhibited tumorigenesis in vivo. Mechanistic investigations demonstrated that LINC01234 might act as a competing endogenous RNA (ceRNA) for miR-429 to regulate the SYNJ1 expression. The effects of miR-429 and SYNJ1 in MDA-MB-231 cells were also analyzed. Our results revealed that the novel LINC01234/miR-429/SYNJ1 axis played a critical role in progression of TNBC cell line MDA-MB-231, and it may serve as a therapeutic target for TNBC.

The Role of Long Non-Coding RNA and microRNA Networks in Hepatocellular Carcinoma and Its Tumor Microenvironment

Hepatocellular carcinoma (HCC) is a common liver malignancy with high morbidity and poor prognosis. Long non-coding RNAs (lncRNAs) are involved in crucial biological processes of tumorigenesis and progression, and play four major regulatory roles, namely signal, decoy, guide, and scaffold, to regulate gene expression. Through these processes, lncRNAs can target microRNAs (miRNAs) to form lncRNA and miRNA networks, which regulate cancer cell proliferation, metastasis, drug resistance, and the tumor microenvironment. Here, we summarize the multifaceted functions of lncRNA and miRNA networks in the pathogenesis of HCC, the potential use of diagnostic or prognostic biomarkers, and novel therapeutic targets in HCC. This review also highlights the regulatory effects of lncRNA and miRNA networks in the tumor microenvironment of HCC.

Elevated Stratifin promotes cisplatin-based chemotherapy failure and poor prognosis in non-small cell lung cancer

Drug resistance is a key factor in the treatment failure of clinical non-small cell lung cancer (NSCLC) patients after adjuvant chemotherapy. Here, our results provide the first evidence that eukaryotic translation initiation factor 2b subunit delta (EIF2B4)-Stratifin (SFN) fusion and increased SFN expression are associated with chemotherapy tolerance and activation of the phosphatidylinositol 3 kinase/v-akt murine thymoma viral oncogene (PI3K/Akt) signaling pathway in NSCLC patients, suggesting that SFN might have potential prognostic value as a tumor biomarker for the prognosis of patients with NSCLC.

Dysregulation of Non-coding RNAs mediates Cisplatin Resistance in Hepatocellular Carcinoma and therapeutic strategies

Hepatocellular carcinoma (HCC) is the fourth major contributor to cancer-related deaths worldwide, and patients mostly have poor prognosis. Although several drugs have been approved for the treatment of HCC, cisplatin (CDDP) is still applied in treatment of HCC as a classical chemotherapeutic drug. Unfortunately, the emergence of CDDP resistance has caused HCC patients to exhibit poor drug response. How to mitigate or even reverse CDDP resistance is an urgent clinical issue to be solved. Because of critical roles in biological functional processes and disease developments, non-coding RNAs (ncRNAs) have been extensively studied in HCC in recent years. Importantly, ncRNAs have also been demonstrated to be involved in the development of HCC to CDDP resistance process. Therefore, this review highlighted the regulatory roles of ncRNAs in CDDP resistance of HCC, elucidated the multiple potential mechanisms by which HCC develops CDDP resistance, and attempted to propose multiple drug delivery systems to alleviate CDDP resistance. Recently, ncRNA-based therapy may be a feasible strategy to alleviate CDDP resistance in HCC. Meanwhile, nanoparticles can overcome the deficiencies in ncRNA-based therapy and make it possible to reverse tumor drug resistance. The combined use of these strategies provides clues for reversing CDDP resistance and overcoming the poor prognosis of HCC.

Long non-coding RNA FGD5-AS1 contributes to cisplatin resistance in hepatocellular carcinoma via sponging microRNA-153-3p by upregulating Twinfilin Actin Binding Protein 1 (TWF1)

Long non-coding RNA (lncRNA) FGD5 antisense RNA 1 (FGD5-AS1) was reported to exert critical roles in multiple cancers. The current work aimed to determine the role of FGD5-AS1 in cisplatin (DDP) resistance of hepatocellular carcinoma (HCC). The levels of FGD5-AS1, miR-153-3p, and twinfilin actin binding protein 1 (TWF1) were analyzed using RT-qPCR. CCK-8, colony formation, Transwell, and TUNEL assays were used to examine the IC₅₀ value of DDP, cell viability, invasion, and apoptosis. The interaction between miR-153-3p and TWF1 or FGD5-AS1 was determined by luciferase reporter and RIP assays. In our study, we found that FGD5-AS1 level was elevated in DDP-resistant HCC tissues and cell lines. FGD5-AS1 silencing improved the sensitivity of HCC cells to DDP. Moreover, FGD5-AS1 directly bound to miR-153-3p and FGD5-AS1 addition neutralized the inhibitory impacts of miR-153-3p supplementation on DDP resistance in the HCC cells. In addition, knockdown of TWF1 inhibited DDP resistance of HCC cells, which was reversed by miR-153-3p deletion. Lastly, FGD5-AS1 interference decreased TWF1 expression level, which was rescued by miR-153-3p inhibition. Our study exhibited that FGD5-AS1 promoted DDP resistance through modulating the miR-153-3p/TWF1 axis in HCC cells. This could be an effective treatment strategy for HCC patients.

Keep your eyes peeled for long noncoding RNAs: Explaining their boundless role in cancer metastasis, drug resistance, and clinical application

Cancer metastasis and drug resistance are two major obstacles in the treatment of cancer and therefore, the leading cause of cancer-associated mortalities worldwide. Hence, an in-depth understanding of these processes and identification of the underlying key players could help design a better therapeutic regimen to treat cancer. Earlier thought to be merely transcriptional junk and having passive or secondary function, recent advances in the genomic research have unravelled that long noncoding RNAs (lncRNAs) play pivotal roles in diverse physiological as well as pathological processes including cancer metastasis and drug resistance. LncRNAs can regulate various steps of the complex metastatic cascade such as epithelial-mesenchymal transition (EMT), invasion, migration and metastatic colonization, and also affect the sensitivity of cancer cells to various chemotherapeutic drugs. A substantial body of literature for more than a decade of research evince that lncRNAs can regulate gene expression at different levels such as epigenetic, transcriptional, posttranscriptional, translational and posttranslational levels, depending on their subcellular localization and through their ability to interact with DNA, RNA and proteins. In this review, we mainly focus on how lncRNAs affect cancer metastasis by modulating expression of key metastasis-associated genes at various levels of gene regulation. We also discuss how lncRNAs confer cancer cells either sensitivity or resistance to various chemo-therapeutic drugs via different mechanisms. Finally, we highlight the immense potential of lncRNAs as prognostic and diagnostic biomarkers as well as therapeutic targets in cancer.

Prognostic Value of Melanoma-Associated Antigen-A (MAGE-A) Gene Expression in Various Human Cancers: A Systematic Review and Meta-analysis of 7428 Patients and 44 Studies

Background

Members of the melanoma-associated antigen-A (MAGE-A) subfamily are overexpressed in many cancers and can drive cancer progression, metastasis, and therapeutic recurrence.

Objective

This study is the first comprehensive meta-analysis evaluating the prognostic utility of MAGE-A members in different cancers.

Methods

A systematic literature search was conducted in PubMed, Google Scholar, Science Direct, and Web of Science. The pooled hazard ratios with 95% confidence intervals were estimated to evaluate the prognostic significance of MAGE-A expression in various cancers.

Results

In total, 44 eligible studies consisting of 7428 patients from 11 countries were analysed. Univariate and multivariate analysis for overall survival, progression-free survival, and disease-free survival showed a significant association between high MAGE-A expression and various cancers (P < 0.00001). Additionally, subgroup analysis demonstrated that high MAGE-A expression was significantly associated with poor prognosis for lung, gastrointestinal, breast, and ovarian cancer in both univariate and multivariate analysis for overall survival.

Conclusion

Overexpression of MAGE-A subfamily members is linked to poor prognosis in multiple cancers. Therefore, it could serve as a potential prognostic marker of poor prognosis in cancers.

Electronic supplementary material

The online version of this article (10.1007/s40291-020-00476-5) contains supplementary material, which is available to authorized users.

miR-137/ERRα axis mediates chemoresistance of nasopharyngeal carcinoma cells

Nasopharyngeal carcinoma (NPC) is the most common malignant tumor of the head and neck region and is characterized by an increased risk of developing chemoresistance after treatment. The present study demonstrated that estrogen-related receptor α (ERRα) was upregulated in cisplatin- and fluorouracil-resistant NPC cells. In addition, ERRα knockdown or treatment of cells with the ERRα inverse agonist XCT-790 attenuated the chemoresistance of NPC cells. Mechanistically, the increased expression of ERRα in chemoresistant cells was associated with enhanced mRNA stability. Bioinformatics analysis for screening microRNAs (miRs) regulating the expression of ERRα revealed that miR-137 was downregulated in chemoresistant NPC cells. Additionally, transfection of cells with miR-137 mimics reduced ERRα mRNA stability and increased the chemosensitivity of NPC cells. Furthermore, ERRα knockdown reduced glucose consumption, and lactate and ATP production rates in chemoresistant cells. The aforementioned findings suggested that the miR-137/ERRα-mediated metabolic programming could be involved in the chemoresistance of NPC cells.

Targeting Long Non-Coding RNAs in Hepatocellular Carcinoma: Progress and Prospects

Hepatocellular carcinoma is the fifth-ranked cancer worldwide with a relatively low five-year survival rate. Long non-coding RNAs are a group of RNAs with remarkable aberrant expression which could act on multiple bioprocesses and ultimately impact upon tumor proliferation, invasion, migration, metastasis, apoptosis, and therapy resistance in cancer cells including hepatocellular carcinoma cells. In recent years, long non-coding RNAs have been reported to be indispensable targets in clinical target therapy to stop the growth of cancer and prolong the lifespan of patients with hepatocellular carcinoma. In this review, we enumerate the signaling pathways and life activities affected by long non-coding RNAs in hepatocellular carcinoma cells to illustrate the role of long non-coding RNAs in the development and therapy resistance of hepatocellular carcinoma.

Transcriptomic characterization of cancer-testis antigens identifies MAGEA3 as a driver of tumor progression in hepatocellular carcinoma

Cancer testis antigens (CTAs) are an extensive gene family with a unique expression pattern restricted to germ cells, but aberrantly reactivated in cancer tissues. Studies indicate that the expression (or re-expression) of CTAs within the MAGE-A family is common in hepatocellular carcinoma (HCC). However, no systematic characterization has yet been reported. The aim of this study is to perform a comprehensive profile of CTA de-regulation in HCC and experimentally evaluate the role of MAGEA3 as a driver of HCC progression. The transcriptomic analysis of 44 multi-regionally sampled HCCs from 12 patients identified high intra-tumor heterogeneity of CTAs. In addition, a subset of CTAs was significantly overexpressed in histologically poorly differentiated regions. Further analysis of CTAs in larger patient cohorts revealed high CTA expression related to worse overall survival and several other markers of poor prognosis. Functional analysis of MAGEA3 was performed in human HCC cell lines by gene silencing and in a genetic mouse model by overexpression of MAGEA3 in the liver. Knockdown of MAGEA3 decreased cell proliferation, colony formation and increased apoptosis. MAGEA3 overexpression was associated with more aggressive tumors in vivo. In conclusion MAGEA3 enhances tumor progression and should be considered as a novel therapeutic target in HCC.

Construction of a Myc-associated ceRNA network reveals a prognostic signature in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) remains an extremely lethal disease worldwide. High-throughput methods have revealed global transcriptome dysregulation; however, a comprehensive investigation of the complexity and behavioral characteristics of the competing endogenous RNA (ceRNA) network in HCC is lacking. In this study, we extracted the transcriptome (RNA) sequencing data of 371 HCC patients from The Cancer Genome Atlas platform. With the comparison of the high Myc expression (Myc^high) tumor and low Myc expression (Myc^low) tumor groups in HCC, we identified 1,125 differentially expressed (DE) mRNAs, 589 long non-coding RNAs (lncRNAs), and 93 microRNAs (miRNAs). DE RNAs predicted the interactions necessary to construct an associated Myc ceRNA network, including 19 DE lncRNAs, 5 miRNAs, and 72 mRNAs. We identified a significant signature (long intergenic non-protein-coding [LINC] RNA 2691 [LINC02691] and LINC02499) that effectively predicted overall survival and had protective effects. The target genes of microRNA (miR)-212-3p predicted to intersect with DE mRNAs included SEC14-like protein 2 (SEC14L2) and solute carrier family 6 member 1 (SLC6A1), which were strongly correlated with survival and prognosis. With the use of the lncRNA-miRNA-mRNA axis, we constructed a ceRNA network containing four lncRNAs (LINC02691, LINC02499, LINC01354, and NAV2 antisense RNA 4), one miRNA (miR-212-3p), and two mRNAs (SEC14L2 and SLC6A1). Overall, we successfully constructed a mutually regulated ceRNA network and identified potential precision-targeted therapies and prognostic biomarkers.

MIRLET7BHG promotes hepatocellular carcinoma progression by activating hepatic stellate cells through exosomal SMO to trigger Hedgehog pathway

Hepatocellular carcinoma (HCC), commonly caused by liver fibrosis, is a global challenge with high morbidity. Activation of hepatic stellate cells (HSCs) contributes to hepatic fibrosis. Exosomes are small vesicles that play a significant role in cell-to-cell communication. Smoothened (SMO) is the key signal transducer for Hedgehog pathway. This study was designed to study the function and underlying mechanism of SMO in HSC activation. Functional assays including 5-Ethynyl-2´-deoxyuridine, colony formation, wound healing, transwell, and sphere formation assays disclosed the function of SMO. Western blot analysis of exosome biomarkers, immunofluorescence staining assay, electron microscope, and flow cytometry revealed the existence of exosomes. Bioinformatics analyses and mechanistic assays uncovered the interplays between RNAs. Nude mice xenograft model was established to evaluate HCC tumor growth. We uncovered that SMO was an oncogene in HCC cells and was low-expressed in quiescent HSCs. Then, SMO was upregulated in HSCs cultured with HCC cells-conditioned medium. Next, it was revealed that HCC cells-derived exosomes activated HSCs by transmitting SMO to HSCs. Subsequently, we recognized that microRNA let-7b host gene (MIRLET7BHG) served as the competing endogenous RNA against miR-330-5p to upregulate SMO. In turn, SMO induced hedgehog pathway to promote GLI family zinc finger 1 (Gli1), leading to transcriptional activation of MIRLET7BHG in activated HSCs. In summary, this study demonstrated that Gli1-induced MIRLET7BHG facilitated HCC by activating HSCs through exosomal SMO to stimulate hedgehog pathway, providing a new road for HCC treatment.

MicroRNA-497-5p Is Downregulated in Hepatocellular Carcinoma and Associated with Tumorigenesis and Poor Prognosis in Patients

Background

MicroRNAs (miRNAs) have been demonstrated to exhibit important regulatory roles in multiple malignancies, including hepatocellular carcinoma (HCC). hsa-miR-497-5p was reported to involve in cancer progression and poor prognosis in many kinds of tumors. However, the expression and its clinical significance of hsa-miR-497-5p in HCC remain unclear.

Methods

In the present study, we investigated the expression of hsa-miR-497-5p in HCC and analyzed the correction of clinical features with prognosis. The expression levels of hsa-miR-497-5p and potential target genes were analyzed in HCC and adjacent noncancerous tissues using The Cancer Genome Atlas (TCGA) database and Gene Expression Omnibus (GEO) datasets. Real-time quantitative reverse transcription polymerase chain reaction (qRT-PCR) was used to analyze hsa-miR-497-5p levels in 328 HCC tissues and 30 paired adjacent noncancer tissues. Overall survival (OS) and progression-free survival (PFS) of patients with HCC were assessed using the Kaplan-Meier method and the log-rank test.

Results

The hsa-miR-497-5p expression levels were decreased, and its target genes ACTG1, CSNK1D, PPP1CC, and BIRC5 were upregulated in HCC tissues compared with normal tissues. Lower levels of hsa-miR-497-5p expression and higher levels of the four target genes were significantly associated with higher tumor diameter. Moreover, patients with lower hsa-miR-497-5p expression and higher target genes levels had shorter OS.

Conclusion

The expression levels of hsa-miR-497-5p may play an important regulatory role in HCC and are closely correlated with HCC progression and poor prognosis in patients. The hsa-miR-497-5p may be a specific therapeutic target for the treatment of HCC.

Sulfasalazine synergistically enhances the inhibitory effects of imatinib against hepatocellular carcinoma (HCC) cells by targeting NFκB, BCR/ABL, and PI3K/AKT signaling pathway-related proteins

Hepatocellular carcinoma (HCC) is the third leading cause of cancer-related fatalities worldwide. Identification of second-line therapies for patients with progressive HCC is urgently required as the use of sorafenib and/or regorafenib remains unsatisfactory. Imatinib, a small-molecule kinase inhibitor, is used to treat certain types of cancer, and nuclear factor κB (NFκB) is a positive regulator of cancer cell expansion. The combined use of tyrosine kinase and NFκB inhibitors may have potential for treating HCC. The aim of this work was to assess the potential anticarcinogenic effects of imatinib and sulfasalazine alone or in combination on the human HCC cell lines HEPG2 and Huh-7. Both drugs were shown to affect the phosphoinositide 3-kinase/protein kinase B, phosphorylated signal transducer and activator of translation (p-STAT-3), breakpoint cluster region protein/Abelson proto-oncogene and NFκB pathways. At the transcriptional level, imatinib and sulfasalazine were found to synergistically down-regulate c-MET gene expression. When compared with the activities of either medication alone, combined use of imatinib and sulfasalazine enhanced inhibition of HCC cell proliferation and extended induction of apoptosis. In summary, the presented data suggest that sulfasalazine synergistically potentiates the antitumor effects of imatinib.

STAT3-induced HLA-F-AS1 promotes cell proliferation and stemness characteristics in triple negative breast cancer cells by upregulating TRABD

Breast cancer (BC) is one of the most common malignances and is a leading cause of cancer-related deaths in women globally. Triple negative breast cancer (TNBC) is a common subtype of BC. Emerging evidence has indicated the crucial roles of long noncoding RNAs (lncRNAs) in the tumorigenesis of TNBC. Our aim was to explore the role and regulatory mechanism of lncRNA HLA-F antisense RNA 1 (HLA-F-AS1) in TNBC cells. Cell counting kit-8 (CCK-8) assay, colony formation assay, flow cytometry analysis and western blot analysis were used to measure HLA-F-AS1-mediated cellular behaviors in TNBC. Xenograft tumor assay was applied to assess biological function of HLA-F-AS1 in vivo. Luciferase reporter assay and RNA pull down assay were used to verify the binding ability between molecules. Our findings demonstrated that HLA-F-AS1 expression was significantly upregulated in TNBC tissues and cells, and high level of HLA-F-AS1 indicated the poor prognosis of patients with TNBC. HLA-F-AS1 promoted TNBC progression by facilitating cell proliferation and stemness maintenance and inhibiting cell cycle arrest at G0/G1 stage and apoptosis in vitro as well as inducing tumor growth in vivo. HLA-F-AS1. In addition, signal transducer and activator of transcription 3 (STAT3) transcriptionally induced HLA-F-AS1 upregulation in TNBC cells via interacting with HLA-F-AS1 promoter. Moreover, HLA-F-AS1 acted as the molecular sponge of microRNA 541-3p (miR-541-3p) to elevate TRABD (TraB domain containing) expression in TNBC cells. Rescue experiments confirmed that the decrease of cell proliferation and stemness characteristics under silenced HLA-F-AS1 was rescued by TRABD overexpression in TNBC cells. In conclusion, STAT3-induced HLA-F-AS1 facilitates cell proliferation and stemness characteristics in TNBC by miR-541-3p-dependent upregulation of TRABD, which might provide a potential novel direction for the treatment of TNBC.

Exploring the Effect of Differentially Expressed Long Non-coding RNAs Driven by Copy Number Variation on Competing Endogenous RNA Network by Mining Lung Adenocarcinoma Data

Lung cancer is the first cause of cancer death, and gene copy number variation (CNV) is a vital cause of lung cancer progression. Prognosis prediction of patients followed by medication guidance by detecting CNV of lung cancer is emerging as a promising precise treatment in the future. In this paper, the differences in CNV and gene expression between cancer tissue and normal tissue of lung adenocarcinoma (LUAD) from The Cancer Genome Atlas Lung Adenocarcinoma data set were firstly analyzed, and greater differences were observed. Furthermore, CNV-driven differentially expressed long non-coding RNAs (lncRNAs) were screened out, and then, a competing endogenous RNA (ceRNA) regulatory network related to the gene CNV was established, which involved 9 lncRNAs, seven microRNAs, and 178 downstream messenger RNAs (mRNAs). Pathway enrichment analyses sequentially performed revealed that the downstream mRNAs were mainly enriched in biological pathways related to cell division, DNA repair, and so on, indicating that these mRNAs mainly affected the replication and growth of tumor cells. Besides, the relationship between lncRNAs and drug effects was explored based on previous studies, and it was found that LINC00511 and LINC00942 in the CNV-associated ceRNA network could be used to determine tumor response to drug treatment. As examined, the drugs affected by these two lncRNAs mainly targeted metabolism, target of rapamycin signaling pathway, phosphatidylinositol-3-kinase signaling pathway, epidermal growth factor receptor signaling pathway, and cell cycle. In summary, the present research was devoted to analyzing CNV, lncRNA, mRNA, and microRNA of lung cancer, and nine lncRNAs that could affect the CNV-associated ceRNA network we constructed were identified, two of which are promising in determining tumor response to drug treatment.

SFPQ promotes an oncogenic transcriptomic state in melanoma

The multifunctional protein, splicing factor, proline- and glutamine-rich (SFPQ) has been implicated in numerous cancers often due to interaction with coding and non-coding RNAs, however, its role in melanoma remains unclear. We report that knockdown of SFPQ expression in melanoma cells decelerates several cancer-associated cell phenotypes, including cell growth, migration, epithelial to mesenchymal transition, apoptosis, and glycolysis. RIP-seq analysis revealed that the SFPQ-RNA interactome is reprogrammed in melanoma cells and specifically enriched with key melanoma-associated coding and long non-coding transcripts, including SOX10, AMIGO2 and LINC00511 and in most cases SFPQ is required for the efficient expression of these genes. Functional analysis of two SFPQ-enriched lncRNA, LINC00511 and LINC01234, demonstrated that these genes independently contribute to the melanoma phenotype and a more detailed analysis of LINC00511 indicated that this occurs in part via modulation of the miR-625-5p/PKM2 axis. Importantly, analysis of a large clinical cohort revealed that elevated expression of SFPQ in primary melanoma tumours may have utility as a prognostic biomarker. Together, these data suggest that SFPQ is an important driver of melanoma, likely due to SFPQ-RNA interactions promoting the expression of numerous oncogenic transcripts.

Long Non-Coding RNAs: Potential Biomarkers and Targets for Hepatocellular Carcinoma Therapy and Diagnosis

Hepatocellular carcinoma (HCC) is one of the leading causes of cancer-related death worldwide. Increasing studies showed that long non-coding RNAs (lncRNAs), a novel class of RNAs that are greater than 200 nucleotides in length but lack the ability to encode proteins, exert crucial roles in the occurrence and progression of HCC. LncRNAs promote the proliferation, migration, invasion, autophagy, and apoptosis of tumor cells by regulating downstream target gene expression and cancer-related signaling pathways. Meanwhile, lncRNA can be used as biomarkers to predict the efficacy of HCC treatment strategies, such as surgery, radiotherapy, chemotherapy, and immunotherapy, and as a potential individualized tool for HCC diagnosis and treatment. In this review, we overview up-to-date findings on lncRNAs as potential biomarkers for HCC surgery, radiotherapy, chemotherapy resistance, target therapy, and immunotherapy, and discuss the potential clinical application of lncRNA as tools for HCC diagnosis and treatment.

Downregulation of lncRNA FGF12-AS2 suppresses the tumorigenesis of NSCLC via sponging miR-188-3p

Background

Non-small-cell lung carcinoma (NSCLC) seriously threatens the health of human beings. Aberrant expression of lncRNAs has been confirmed to be related with the progression of multiple malignant tumors, including NSCLC. LncRNA FGF12-AS2 has been considered to be upregulated in NSCLC. However, the mechanism by which FGF12-AS2 promotes the tumorigenesis of NSCLC remains elusive.

Methods

Gene and protein expressions in NSCLC cells were measured by q-PCR and western blot, respectively. CCK-8 and immunofluorescence staining were performed to detect the cell proliferation. Cell apoptosis was tested by flow cytometry. Transwell assay was used to detect the cell migration and invasion. Finally, the dual luciferase report assay was used to verify the relation among FGF12-AS2, miR-188-3p, and NCAPG2.

Results

Downregulation of FGF12-AS2 significantly inhibited the proliferation of NSCLC cells via inducing apoptosis. In addition, FGF12-AS2 silencing notably suppressed the migration and invasion of A549 cells. Meanwhile, FGF12-AS2 modulated the progression of NSCLC via regulation of miR-188-3p/NCAPG2 axis. Finally, knockdown of FGF12-AS2 inhibited the tumorigenesis of NSCLC via suppressing the EMT process of NSCLC.

Conclusion

Downregulation of lncRNA FGF12-AS2 suppressed the tumorigenesis of NSCLC via sponging miR-188-3p. Thus, FGF12-AS2 may serve as a potential target for the treatment of NSCLC.

Long non-coding RNAs MACC1-AS1 and FOXD2-AS1 mediate NSD2-induced cisplatin resistance in esophageal squamous cell carcinoma

The nuclear receptor-binding SET domain (NSD) protein family encoding histone lysine methyltransferases is involved in cancer progression. However, the role of NSDs in esophageal squamous cell carcinoma (ESCC) remains unclear. Here we examined the expression of NSDs in cisplatin-resistant and parental ESCC cells and revealed the upregulation of NSD2 in cisplatin-resistant cells. Ectopic expression of NSD2 increased cisplatin resistance and attenuated cisplatin-induced apoptosis. Colony formation assay indicated that NSD2 overexpression enhanced long-term survival of ESCC cells after treatment with cisplatin. In contrast, knockdown of NSD2 inhibited ESCC cell proliferation and sensitized ESCC cells to cisplatin. Depletion of NSD2 augmented the cytotoxic effect of cisplatin on EC109 xenograft tumors. NSD2 stimulated long non-coding RNA MACC1-AS1 in ESCC cells. Knockdown of MACC1-AS1 impaired NSD2-induced cisplatin resistance. Moreover, MACC1-AS1 overexpression promoted ESCC cell proliferation and cisplatin resistance. Clinically, MACC1-AS1 was upregulated in ESCC relative to adjacent noncancerous tissues. High MACC1-AS1 levels were significantly associated with reduced overall survival of ESCC patients. There was a positive correlation between MACC1-AS1 and NSD2 expression in ESCC specimens. Taken together, MACC1-AS1 induced by NSD2 mediates resistance to cisplatin in ESCC and may represent a novel target to improve cisplatin-based chemotherapy.

Emerging roles of the MAGE protein family in stress response pathways

The melanoma antigen (MAGE) proteins all contain a MAGE homology domain. MAGE genes are conserved in all eukaryotes and have expanded from a single gene in lower eukaryotes to ∼40 genes in humans and mice. Whereas some MAGEs are ubiquitously expressed in tissues, others are expressed in only germ cells with aberrant reactivation in multiple cancers. Much of the initial research on MAGEs focused on exploiting their antigenicity and restricted expression pattern to target them with cancer immunotherapy. Beyond their potential clinical application and role in tumorigenesis, recent studies have shown that MAGE proteins regulate diverse cellular and developmental pathways, implicating them in many diseases besides cancer, including lung, renal, and neurodevelopmental disorders. At the molecular level, many MAGEs bind to E3 RING ubiquitin ligases and, thus, regulate their substrate specificity, ligase activity, and subcellular localization. On a broader scale, the MAGE genes likely expanded in eutherian mammals to protect the germline from environmental stress and aid in stress adaptation, and this stress tolerance may explain why many cancers aberrantly express MAGEs Here, we present an updated, comprehensive review on the MAGE family that highlights general characteristics, emphasizes recent comparative studies in mice, and describes the diverse functions exerted by individual MAGEs.

MicroRNA-31-5p Exacerbates Lipopolysaccharide-Induced Acute Lung Injury via Inactivating Cab39/AMPKα Pathway

Acute lung injury (ALI) and the subsequent acute respiratory distress syndrome remain devastating diseases with high mortality rates and poor prognoses among patients in intensive care units. The present study is aimed at investigating the role and underlying mechanisms of microRNA-31-5p (miR-31-5p) on lipopolysaccharide- (LPS-) induced ALI. Mice were pretreated with miR-31-5p agomir, antagomir, and their negative controls at indicated doses for 3 consecutive days, and then they received a single intratracheal injection of LPS (5 mg/kg) for 12 h to induce ALI. MH-S murine alveolar macrophage cell lines were cultured to further verify the role of miR-31-5p in vitro. For AMP-activated protein kinase α (AMPKα) and calcium-binding protein 39 (Cab39) inhibition, compound C or lentiviral vectors were used in vivo and in vitro. We observed an upregulation of miR-31-5p in lung tissue upon LPS injection. miR-31-5p antagomir alleviated, while miR-31-5p agomir exacerbated LPS-induced inflammation, oxidative damage, and pulmonary dysfunction in vivo and in vitro. Mechanistically, miR-31-5p antagomir activated AMPKα to exert the protective effects that were abrogated by AMPKα inhibition. Further studies revealed that Cab39 was required for AMPKα activation and pulmonary protection by miR-31-5p antagomir. We provide the evidence that endogenous miR-31-5p is a key pathogenic factor for inflammation and oxidative damage during LPS-induced ALI, which is related to Cab39-dependent inhibition of AMPKα.

TAZ-regulated expression of IL-8 is involved in chemoresistance of hepatocellular carcinoma cells

Chemotherapy resistance is one of the major challenges for the treatment of hepatocellular carcinoma (HCC). In order to investigate the mechanisms involved in chemoresistance of HCC, we established cisplatin (CDDP) and doxorubicin (Dox) resistant HCC cells. The expression of transcriptional coactivator with PDZ-binding motif (TAZ), one of the major downstream effectors of Hippo pathway, was upregulated in chemoresistant HCC cells. Targeted inhibition of TAZ via its siRNAs can restore CDDP and Dox sensitivity of chemoresistant HCC cells. The upregulation of TAZ increased the expression of IL-8 in HCC/CDDP and HCC/Dox cells. Recombinant IL-8 (rIL-8) antagonized the increased chemosensitivity mediated by TAZ knockdown. Mechanistically, TAZ can directly bind with the promoter of IL-8 to activate its transcription in chemoresistant HCC cells. Collectively, our data showed that TAZ-regulated expression of IL-8 was involved in chemoresistance of HCC cells. It indicated that targeted inhibition of TAZ/IL-8 axis might be helpful to improve chemotherapy efficiency for HCC.