FOXC1 Regulation of miR-31-5p Confers Oxaliplatin Resistance by Targeting LATS2 in Colorectal Cancer

Promoter of lncRNA MORT is aberrantly methylated in colorectal cancer

Aberrant DNA methylation plays essential roles in the colorectal cancer (CRC) carcinogenesis and has been demonstrated as a promising marker for cancer early detection. In this project, methylation status of the MORT promoter was studied in CRC and their marginal tissues using qMSP assay. Furthermore, we investigated the molecular function of MORT in CRC progression using computational analysis. The results showed a high methylation level of MORT promoter in CRC tissues. By in silico analysis, we found that MORT downregulation could promote the proliferation of CRC cells via sponging of has-miR-574-5p and has-miR-31-5p, and alteration of their targets expression pattern such as MYOCD and FOXP2. In conclusion, based on our results, promoter hypermethylation of MORT might be considered as a potential biomarker for CRC detection.

Novel chromium (III)-based compound for inhibition of oxaliplatin-resistant colorectal cancer progression

Colorectal cancer (CRC) ranks as the third leading cause of cancer-related mortality worldwide. The current standard of care includes systemic chemotherapy with cytotoxic agents, offering palliative relief for severe CRC cases and serving as the primary therapy for metastatic recurrence. However, the development of chemoresistance poses a substantial obstacle in the realm of chemotherapy. This study delved into the potential of a novel chromium (III)-based compound, hexaacetotetraaquadihydroxochromium (III) diiron (III) nitrate, for CRC treatment. The therapeutic promise of this innovative chromium (III)-based compound was explored by utilizing LoVo colon cancer cells and an in-vivo mouse model of CRC. Various dosages of the compound were administered to LoVo parental cells and LoVo oxaliplatin-resistant cells. Findings unveiled that a concentration of 2000 μg/mL of the chromium (III) compound significantly inhibited mesenchymal transition and the migratory and invasive properties of LoVo oxaliplatin-resistant cells. This novel chromium (III)-based compound also demonstrated similar efficacy in other different CRC cell lines. The tumor growth was in the in-vivo mouse model was reduced by this compound. Moreover, the chromium (III)-based compound induced apoptosis by triggering the endoplasmic reticulum (ER) stress pathway in LoVo oxaliplatin-resistant cells. This study illuminates the capacity of the novel chromium (III)-based compound to impede the progression and growth of chemotherapy-resistant CRC. This discovery instills confidence in the potential of this compound as a therapeutic agent for CRC, even in the face of drug resistance. It holds the promise of serving as a valuable asset in the future treatment of chemotherapy-resistant CRC.

Biological landscape and nanostructural view in development and reversal of oxaliplatin resistance in colorectal cancer

The treatment of cancer patients has been mainly followed using chemotherapy and it is a gold standard in improving prognosis and survival rate of patients. Oxaliplatin (OXA) is a third-platinum anti-cancer agent that reduces DNA synthesis in cancer cells to interfere with their growth and cell cycle progression. In spite of promising results of using OXA in cancer chemotherapy, the process of drug resistance has made some challenges. OXA is commonly applied in treatment of colorectal cancer (CRC) as a malignancy of gastrointestinal tract and when CRC cells increase their proliferation and metastasis, they can obtain resistance to OXA chemotherapy. A number of molecular factors such as CHK2, SIRT1, c-Myc, LATS2 and FOXC1 have been considered as regulators of OXA response in CRC cells. The non-coding RNAs are able to function as master regulator of other molecular pathways in modulating OXA resistance. There is a close association between molecular mechanisms such as apoptosis, autophagy, glycolysis and EMT with OXA resistance, so that apoptosis inhibition, pro-survival autophagy induction and stimulation of EMT and glycolysis can induce OXA resistance in CRC cells. A number of anti-tumor compounds including astragaloside IV, resveratrol and nobiletin are able to enhance OXA sensitivity in CRC cells. Nanoparticles for increasing potential of OXA in CRC suppression and reversing OXA resistance have been employed in cancer chemotherapy. These subjects are covered in this review article to shed light on molecular factors resulting in OXA resistance.

Induction of resistance to oxaliplatin in cancer by a microRNA/Fem1B/Gli1 pathway

Colorectal cancer is among the most common cancers worldwide and a frequent cause of cancer related deaths. Oxaliplatin is the first line chemotherapeutics for treatment, but the development of resistance leads to recurrence of oxaliplatin insensitive tumors. To understand possible mechanisms of drug tolerance we developed oxaliplatin resistant derivatives (OR-LoVo) of the established LoVo cell line originally isolated from a metastatic colon adenocarcinoma. We compared the microRNA (miRNA) expression profile of the cell pair and found expression of miR-29a-3p significantly increased in OR-LoVo cells compared to parent cells. In addition, miR-29a-3p was significantly elevated in tumor tissue when compared to matched surrounding tissue in human, suggesting potential clinical importance. Ectopic miR-29-a-3p expression induced chemoresistance in a number of different cancer cell lines as well as colorectal tumors in mice. We further demonstrated that miR-29-a-3p downregulates expression of the ubiquitin ligase component FEM1B and that reduction of Fem1b levels is sufficient to confer oxaliplatin resistance. FEM1B targets the glioma associated oncogene Gli1 for degradation, suggesting that increased Gli1 levels could contribute to oxaliplatin tolerance. Accordingly, knockdown of GLI1 reverted chemoresistance of OR-LoVo cells. Mechanistically, resistant cells experienced significantly lower DNA damage upon oxaliplatin treatment, which can be partially explained by reduced oxaliplatin uptake and enhanced repair. These results suggest that miR-29-a-3p overexpression induces oxaliplatin resistance through misregulation of Fem1B and Gli1 levels. TCGA analyses provides strong evidence that the reported findings regarding induced drug tolerance by the miR-29a/Fem1B axis is clinically relevant. The reported findings can help to predict oxaliplatin sensitivity and resistance of colorectal tumors.

Rewiring of IGF1 secretion and enhanced IGF1R signaling induced by co-chaperone carboxyl-terminus of Hsp70 interacting protein in adipose-derived stem cells provide augmented cardioprotection in aging-hypertensive rats

Aging-associated cardiovascular diseases depend on the longitudinal deterioration of stem cell dynamics. The entire mechanism behind it is not completely understood. However, many studies suggest that endocrine pathways, particularly the insulin-like growth factor-1(IGF1) signaling pathway are involved in cardioprotection, especially in stem-cell treatments. Here, we investigated the role of a co-chaperone, carboxyl-terminus of Hsp70 interacting protein (CHIP) in the aspects of growth factor secretion and receptor stabilization in mesenchymal stem cells (MSCs). Briefly, we overexpressed CHIP in rat adipose-derived stem cells (rADSCs) and explored the consequences in vitro, and in vivo, in spontaneously hypertensive rats (SHR). Our data revealed that CHIP overexpression in rADSCs promoted the secretion of insulin-like growth factor-1 (IGF1) and IGF binding protein-3 (IGFBP3) as per immunoblot/cytokine array analysis. We also found that these results were dependent on the nuclear translocation of signal transducer and activator of transcription 3 (STAT3) in rADSCs. Further, the CHIP co-chaperone was also involved in the stabilization of the receptor of IGF1 (IGF1R); interactions between the beta transmembrane region of IGF1R, and the tetracopeptide repeat (TPR) domain of CHIP were evident. Importantly, after the transplantation of lentiviral CHIP overexpression of rADSCs (rADSCsCHIP-WT) into nine months aging-SHR led to an increase in their cardiac function - increased ejection fraction and fractional shortening (≈15% vs. control SHR) - as well as a decrease in their heart size and heart rate, respectively. Altogether, our results support the use of CHIP overexpressing stem cells for the mitigation of cardiac hypertrophy and remodeling associated with late-stage hypertension.

Role of ELK1 in regulating colorectal cancer progression: miR-31-5p/CDIP1 axis in CRC pathogenesis

Background and Objective

Colorectal cancer (CRC) is a malignant tumor that affects the digestive system. With the increased of modernization of society, the incidence of colorectal cancer has increased throughout the world. As a transcription factor, ELK1 has been widely studied in colorectal cancer. However, there are still many unknown factors regarding its specific mechanism of action.This study explored the role of ELK1 and its downstream pathway in CRC pathogenesis.

Methods

Based on clinical samples, this study examined miR-31-5p expression in CRC cells and its impact on malignant behaviors (migration, invasion, apoptosis) and autophagy. The promoter sequence of miR-31-5p was obtained from the UCSC database, and ELK1 was identified as its transcription factor. In ELK1-knockdown CRC cells, miR-31-5p was overexpressed, and its response in malignant behaviors and autophagy was analyzed. The target gene CDIP1 was predicted and verified using a dual-luciferase assay. The influence of CDIP1 on malignant behavior in CRC cells was assessed, and CDIP1 siRNA was used as a rescue treatment for miR-31-5p inhibition. The role of ELK1/miR-31-5p in tumor growth was validated in vivo.

Results

miR-31-5p expression was upregulated in the colorectal cancer tissues and cells. The knockdown of miR-31-5p markedly inhibited cancer cells' malignant behaviors and mediated autophagy. ELK1 was confirmed to bind with the miR-31-5p promoter and enhance miR-31-5p transcription. miR-31-5p was found to bind with the CDIP1 3'UTR and inhibit CDIP1 expression. CDIP1 siRNA partially rescued the effects of miR-31-5p knockdown on cell metastatic ability, autophagy, and apoptosis. Based on the in vivo experiments, results showed that the ELK1/miR-31-5p axis positively regulated tumor growth in nude mice.

Conclusion

Our findings indicate that ELK1 regulates the progression of colorectal cancer via an miR-31-5p/CDIP1 axis, and the ELK1/miR-31-5p/CDIP1 axis could be a therapeutic target for colorectal cancer.

Unraveling Therapeutic Opportunities and the Diagnostic Potential of microRNAs for Human Lung Cancer

Lung cancer is a major public health problem and a leading cause of cancer-related deaths worldwide. Despite advances in treatment options, the five-year survival rate for lung cancer patients remains low, emphasizing the urgent need for innovative diagnostic and therapeutic strategies. MicroRNAs (miRNAs) have emerged as potential biomarkers and therapeutic targets for lung cancer due to their crucial roles in regulating cell proliferation, differentiation, and apoptosis. For example, miR-34a and miR-150, once delivered to lung cancer via liposomes or nanoparticles, can inhibit tumor growth by downregulating critical cancer promoting genes. Conversely, miR-21 and miR-155, frequently overexpressed in lung cancer, are associated with increased cell proliferation, invasion, and chemotherapy resistance. In this review, we summarize the current knowledge of the roles of miRNAs in lung carcinogenesis, especially those induced by exposure to environmental pollutants, namely, arsenic and benzopyrene, which account for up to 1/10 of lung cancer cases. We then discuss the recent advances in miRNA-based cancer therapeutics and diagnostics. Such information will provide new insights into lung cancer pathogenesis and innovative diagnostic and therapeutic modalities based on miRNAs.

MicroRNA-31 induced by Fusobacterium nucleatum infection promotes colorectal cancer tumorigenesis

Persistent Fusobacterium nucleatum infection is associated with the development of human colorectal cancer (CRC) and promotes tumorigenicity, but the underlying mechanisms remain unclear. Here, we reported that F. nucleatum promoted the tumorigenicity of CRC, which was associated with F. nucleatum-induced microRNA-31 (miR-31) expression in CRC tissues and cells. F. nucleatum infection inhibited autophagic flux by miR-31 through inhibiting syntaxin-12 (STX12) and was associated with the increased intracellular survival of F. nucleatum. Overexpression of miR-31 in CRC cells promoted their tumorigenicity by targeting eukaryotic initiation factor 4F-binding protein 1/2 (eIF4EBP1/2), whereas miR-31 knockout mice were resistant to the formation of colorectal tumors. In conclusion, F. nucleatum, miR-31, and STX12 form a closed loop in the autophagy pathway, and continuous F. nucleatum-induced miR-31 expression promotes the tumorigenicity of CRC cells by targeting eIF4EBP1/2. These findings reveal miR-31 as a potential diagnostic biomarker and therapeutic target in CRC patients with F. nucleatum infection.

Dynamic Role of Exosome microRNAs in Cancer Cell Signaling and Their Emerging Role as Noninvasive Biomarkers

Exosomes are extracellular vesicles that originate from endosomes and are released by all cells irrespective of their origin or type. They play an important role in cell communication and can act in an autocrine, endocrine, or paracrine fashion. They are 40-150 nm in diameter and have a similar composition to the cell of origin. An exosome released by a particular cell is unique since it carries information about the state of the cell in pathological conditions such as cancer. miRNAs carried by cancer-derived exosomes play a multifaceted role by taking part in cell proliferation, invasion, metastasis, epithelial-mesenchymal transition, angiogenesis, apoptosis, and immune evasion. Depending on the type of miRNA that it carries as its cargo, it can render cells chemo- or radiosensitive or resistant and can also act as a tumor suppressor. Since the composition of exosomes is affected by the cellular state, stress, and changes in the environment, they can be used as diagnostic or prognostic biomarkers. Their unique ability to cross biological barriers makes them an excellent choice as vehicles for drug delivery. Because of their easy availability and stability, they can be used to replace cancer biopsies, which are invasive and expensive. Exosomes can also be used to follow the progression of diseases and monitor treatment strategies. A better understanding of the roles and functions of exosomal miRNA can be used to develop noninvasive, innovative, and novel treatments for cancer.

Extracellular Vesicles in Colorectal Cancer: From Tumor Growth and Metastasis to Biomarkers and Nanomedications

Colorectal cancer (CRC) is a leading public health concern due to its incidence and high mortality rates, highlighting the requirement of an early diagnosis. Evaluation of circulating extracellular vesicles (EVs) might constitute a noninvasive and reliable approach for CRC detection and for patient follow-up because EVs display the molecular features of the cells they originate. EVs are released by almost all cell types and are mainly categorized as exosomes originating from exocytosis of intraluminal vesicles from multivesicular bodies, ectosomes resulting from outward budding of the plasma membrane and apoptotic bodies' ensuing cell shrinkage. These vesicles play a critical role in intercellular communications during physiological and pathological processes. They facilitate CRC progression and premetastatic niche formation, and they enable transfer of chemotherapy resistance to sensitive cells through the local or remote delivery of their lipid, nucleic acid and protein content. On another note, their stability in the bloodstream, their permeation in tissues and their sheltering of packaged material make engineered EVs suitable vectors for efficient delivery of tracers and therapeutic agents for tumor imaging or treatment. Here, we focus on the physiopathological role of EVs in CRCs, their value in the diagnosis and prognosis and ongoing investigations into therapeutic approaches.

The FOXC2 Transcription Factor: A Master Regulator of Chemoresistance in Cancer

FOXC2, a member of the forkhead box family of transcription factors, is an emerging oncogene that has been linked to several hallmarks of cancer progression. Among its many oncogenic functions is the promotion of drug resistance, with evidence supporting roles for FOXC2 in escape from broad classes of chemotherapeutics across an array of cancer types. In this Mini-Review, we highlight the current understanding of the mechanisms by which FOXC2 drives cancer chemoresistance, including its roles in the promotion of epithelial-mesenchymal transition, induction of multidrug transporters, activation of the oxidative stress response, and deregulation of cell survival signaling pathways. We discuss the clinical implications of these findings, including strategies for modulating FOXC2-associated chemoresistance in cancer. Particular attention is given to ways in which FOXC2 and its downstream gene products and pathways can be targeted to restore chemosensitivity in cancer cells. In addition, the utility of FOXC2 expression as a predictor of patient response to chemotherapy is also highlighted, with emphasis on the value of FOXC2 as a novel biomarker that can be used to guide therapeutic choice towards regimens most likely to achieve clinical benefit during frontline therapy.

Integrated Microarray-Based Data Analysis of miRNA Expression Profiles: Identification of Novel Biomarkers of Cisplatin-Resistance in Testicular Germ Cell Tumours

Testicular germ cell tumours (TGCTs) are the most common solid malignancy among young men, and their incidence is still increasing. Despite good curability with cisplatin (CDDP)-based chemotherapy, about 10% of TGCTs are non-responsive and show a chemoresistant phenotype. To further increase TGCT curability, better prediction of risk of relapse and early detection of refractory cases is needed. Therefore, to diagnose this malignancy more precisely, stratify patients more accurately and improve decision-making on treatment modality, new biomarkers are still required. Numerous studies showed association of differential expressions of microRNAs (miRNAs) with cancer. Using microarray analysis followed by RT-qPCR validation, we identified specific miRNA expression patterns that discriminate chemoresistant phenotypes in TGCTs. Comparing CDDP-resistant vs. -sensitive TGCT cell lines, we identified miR-218-5p, miR-31-5p, miR-125b-5p, miR-27b-3p, miR-199a-5p, miR-214-3p, let-7a and miR-517a-3p as significantly up-regulated and miR-374b-5p, miR-378a-3p, miR-20b-5p and miR-30e-3p as significantly down-regulated. In patient tumour samples, we observed the highest median values of relative expression of miR-218-5p, miR-31-5p, miR-375-5p and miR-517a-3p, but also miR-20b-5p and miR-378a-3p, in metastatic tumour samples when compared with primary tumour or control samples. In TGCT patient plasma samples, we detected increased expression of miR-218-5p, miR-31-5p, miR-517a-3p and miR-375-5p when compared to healthy individuals. We propose that miR-218-5p, miR-31-5p, miR-375-5p, miR-517-3p, miR-20b-5p and miR-378a-3p represent a new panel of biomarkers for better prediction of chemoresistance and more aggressive phenotypes potentially underlying metastatic spread in non-seminomatous TGCTs. In addition, we provide predictions of the targets and functional and regulatory networks of selected miRNAs.

Modulating Effects of Cancer-Derived Exosomal miRNAs and Exosomal Processing by Natural Products

Cancer-derived exosomes exhibit sophisticated functions, such as proliferation, apoptosis, migration, resistance, and tumor microenvironment changes. Several clinical drugs modulate these exosome functions, but the impacts of natural products are not well understood. Exosome functions are regulated by exosome processing, such as secretion and assembly. The modulation of these exosome-processing genes can exert the anticancer and precancer effects of cancer-derived exosomes. This review focuses on the cancer-derived exosomal miRNAs that regulate exosome processing, acting on the natural-product-modulating cell functions of cancer cells. However, the role of exosomal processing has been overlooked in several studies of exosomal miRNAs and natural products. In this study, utilizing the bioinformatics database (miRDB), the exosome-processing genes of natural-product-modulated exosomal miRNAs were predicted. Consequently, several natural drugs that modulate exosome processing and exosomal miRNAs and regulate cancer cell functions are described here. This review sheds light on and improves our understanding of the modulating effects of exosomal miRNAs and their potential exosomal processing targets on anticancer treatments based on the use of natural products.

Identification of miRNA-mRNA Regulatory Networks Associated with Diabetic Retinopathy using Bioinformatics Analysis

INTRODUCTION

Diabetic retinopathy (DR) is a major complication of diabetes and a leading cause of visual loss. This study aimed to explore biomarkers for DR that may provide additional reference to DR pathogenesis and development.

METHODS

The differentially expressed genes (DEGs) between the DR and control samples in the GSE53257 dataset were identified. Logistics analyses were performed to identify DR-associated miRNAs and genes, and correlation analysis was performed to determine the correlation between them in GSE160306.

RESULTS

A total of 114 DEGs in DR were identified in GSE53257. Three genes, including ATP5A1 (down), DAUFV2 (down), and OXA1L (down), were differentially expressed between DR and control samples in GSE160306. Univariate logistics analysis identified that ATP5A1 (OR=0.007, p = 1.40E-02), NDUFV2 (OR = 0.003, p = 6.40E-03), and OXA1L (OR = 0.093, p = 3.08E-02) were DR-associated genes. ATP5A1 and OXA1L were regulated by multiple miRNAs, of which hsa-let- 7b-5p (OR = 26.071, p = 4.40E-03) and hsa-miR-31-5p (OR = 4.188, p = 5.09E-02) were related to DR. ATP5A1 and OXA1L were closely correlated with each other in DR.

CONCLUSION

The hsa-miR-31-5p-ATP5A1 and hsa-let-7b-5p-OXA1L axes might play novel and important roles in the pathogenesis and development of DR.

Artemisia argyi extract induces apoptosis in human gemcitabine-resistant lung cancer cells via the PI3K/MAPK signaling pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Artemisia argyi H. Lév. & Vaniot (Asteraceae), also called "Chinese mugwort", is frequently used as a herbal medicine in China, Japan, Korea, and eastern parts of Russia. It is known as "ai ye" in China and "Gaiyou" in Japan. In ancient China, the buds and leaves of A. argyi were commonly consumed before and after Tomb-sweeping Day. It is used to treat malaria, hepatitis, cancer, inflammatory diseases, asthma, irregular menstrual cycle, sinusitis, and pathologic conditions of the kidney and liver. Although A. argyi extract (AAE) has shown anti-tumor activity against various cancers, the therapeutic effect and molecular mechanism of AAE remains to be further studied in lung cancer.

AIM OF THE STUDY

This study aimed to demonstrate the anti-tumor effect of AAE and its associated biological mechanisms in CL1-0 parent and gemcitabine-resistant (CL1-0-GR) lung cancer cells.

EXPERIMENTAL PROCEDURE

Human lung cancer cells CL1-0 and CL1-0-GR cells were treated with AAE. Cell viability was assessed using the MTT, colony, and spheroid formation assays. Migration, invasion, and immunofluorescence staining were used to determine the extent of epithelial- mesenchymal transition (EMT). JC-1 and MitoSOX fluorescent assays were performed to investigate the effect of AAE on mitochondria. Apoptosis was detected using the TUNEL assay and flow cytometry with Annexin V staining.

RESULT

We found that A. argyi significantly decreased cell viability and induced apoptosis, accompanied by mitochondrial membrane depolarization and increased ROS levels in both parent cells (CL1-0) and gemcitabine-resistant lung cancer cells (CL1-0-GR). AAE-induced apoptosis is regulated via the PI3K/AKT and MAPK signaling pathways. It also prevents CL1-0 and CL1-0-GR cancer cell invasion, migration, EMT, colony formation, and spheroid formation. In addition, AAE acts cooperative with commercial chemotherapy drugs to enhance tumor spheroid shrinkage.

CONCLUSION

Our study provides the first evidence that A. argyi treatment suppresses both parent and gemcitabine-resistant lung cancer cells by inducing ROS, mitochondrial membrane depolarization, and apoptosis, and reducing EMT. Our finding provides insights into the anti-cancer activity of A. argyi and suggests that A. argyi may serve as a chemotherapy adjuvant that potentiates the efficacy of chemotherapeutic agents.

KRT6A expedites bladder cancer progression, regulated by miR-31-5p

Bladder cancer is one of the most severe life-threatening illnesses worldwide. To contribute to a solution to this public health issue, here, we sought to identify a novel biomarker for the early diagnosis of bladder tumors. We conducted RNA sequence analysis utilizing samples from tumorous tissue and adjacent healthy tissue in bladder cancer patients and found that KRT6A was upregulated in bladder tumor tissues, suggesting that it might be a candidate for involvement in bladder tumorigenesis. Accordingly, we performed a series of experiments to further verify the role of KRT6A in bladder tumor progression. Our results revealed that KRT6A promoted bladder tumor cell viability, proliferation, and adhesion, while diminishing bladder tumor cell apoptosis. We also focused on the role of epigenetics in bladder tumors and verified that KRT6A was a miR-31-5p target gene, and its positive effect on bladder tumor progression was relieved by miR-31-5p. Overall, this study sheds new light regarding a novel oncogenic regulatory axis, KRT6A/miR-31-5p, which is related to bladder tumor growth.

CAFs-secreted exosomal cricN4BP2L2 promoted colorectal cancer stemness and chemoresistance by interacting with EIF4A3

Cancer-associated fibroblasts secreted exosomes (CAFs-exo) are important for tumor carcinogenesis and chemoresistance, but its underlying mechanism in colorectal cancer (CRC) has not yet been clarified. In this study, we investigated the regulatory mechanism of CAFs-exo cricN4BP2L2 on the proliferation, apoptosis, stemness and chemoresistance of LoVo cells. We found that CAFs-exo promoted the oxaliplatin resistance and stemness of LoVo cells, while inhibited the LoVo cell apoptosis. Moreover, knockdown of cricN4BP2L2 in CAFs-exo inhibited the oxaliplatin resistance and stemness characteristics of LoVo cells. Mechanistically, cricN4BP2L2 regulated PI3K/AKT/mTOR axis by binding to EIF4A3. Rescue experiments proved that CAFs-derived exosomal cricN4BP2L2 promoted CRC cells stemness and oxaliplatin resistance by upregulating EIF4A3. Moreover, in vivo experiments showed that depletion of cricN4BP2L2 suppressed CRC tumorigenesis growth. In conclusion, CAFs-exo cricN4BP2L2 promoted the CRC cells stemness and oxaliplatin resistance through EIF4A3/PI3K/AKT/mTOR pathway.

Calreticulin nuclear translocalization alleviates CaM/CaMKII/CREB signaling pathway to enhance chemosensitivity in HDAC inhibitor-resistant hepatocellular carcinoma cells

Calreticulin (CRT) is located in the endoplasmic reticulum (ER), it helps proteins fold correctly inside the ER, and acts as a modulator of Ca²⁺ homeostasis. Aberrant expression of CRT is implicated in several cancer types, qualifying CRT as a potential therapeutic target. However, it remains unclear how CRT affects specific oncogenic pathways. In this study, we used histone deacetylase inhibitors (HDACis) to establish drug-resistant liver cancer cells and further analyzed the molecular mechanism of development of drug resistance in those cells. The 2D gel electrophoresis and RT-PCR data showed that CRT was downregulated in HDACis-resistant cells by comparing with HA22T parental cells. We previously elucidated the development of drug-resistance in HCC cells via activation of PP1-eIF2α pathway, but not via ER stress pathway. Here, we show that thapsigargin induced ER stress through mechanism other than ER stress downstream protein GRP78-PERK to regulate CRT expression in HDACis-R cells. Moreover, the expression level of CRT was not the main cause of apoptosis in HDACis-resistant cells. Mechanistic studies identified the apoptosis factors in the nucleus-the HDACis-mediated overexpression of CRT, CRT translocation to the cell nucleus, and reduced CaM/CaMKII/CREB pathway-that led to chemosensitivity in HDACis-R HCC cells.

Long Non-Coding RNA ZEB2-AS1 Promotes Hepatocellular Carcinoma Progression by Regulating The miR-582-5p/FOXC1 Axis

OBJECTIVE

Long non-coding RNAs (lncRNAs) feature prominently in tumors. Reportedly, lncRNA zinc finger E-box-binding homeobox 2 antisense RNA 1 (ZEB2-AS1) is aberrantly expressed in a variety of tumors. The present study was aimed to explore ZEB2-AS1 functions and determine mechanism in hepatocellular carcinoma (HCC) progression.

MATERIALS AND METHODS

In this experimental study, expressions of ZEB2-AS1, microRNA (miR)-582-5p and forkhead box C1 (FOXC1) mRNA in HCC tissues and cell lines were detected via quantitative reveres transcription polymerase chain reaction (qRT-PCR). After establishing gain- and loss-of-functions models, cell counting kit-8, 5-bromo-2'-deoxyuridine (BrdU), Transwell assays and flow cytometry analysis were conducted to examine HCC cell multiplication, migration, invasion and apoptosis, respectively. The targeted relationship between miR-582- 5p and ZEB2-AS1 was verified via dual-luciferase reporter gene assay. Western blot was utilized for detecting FOXC1 expression in HCC cells after selectively regulating ZEB2-AS1 and miR-582-5p.

RESULTS

In HCC tissues and cells, ZEB2-AS1 expression was increased. High ZEB2-AS1 expression was related to relatively large tumor volume, increased tumor-node-metastasis (TNM) stage and positive lymph node metastasis of the patients. ZEB2-AS1 overexpression facilitated HCC cell multiplication, migration, invasion and suppressed apoptosis, while ZEB2-AS1 knock-down caused the opposite effects. It was also confirmed that ZEB2-AS1 could competitively bind with miR-582-5p to repress its expression, and indirectly up-regulate FOXC1 expression level in HCC cells.

CONCLUSION

The current study revealed that ZEB2-AS1 was over-expressed in HCC tissues and cells. It also upregulated (FOXC1), through sponging miR-582-5p, to promote HCC progression. This provides new perspectives for elucidating the pathogenesis of HCC.

MicroRNA-31: a pivotal oncogenic factor in oral squamous cell carcinoma

Oral squamous cell carcinoma (OSCC) continuously constitutes a major challenge for treatment and prognosis due to approximately half of treated OSCC patients dying from locoregional recurrences and distant metastases. MicroRNA-31 (miR-31), an early mammalian miRNA identified, has been gaining importance in the field of OSCC research in recent years. This comprehensive review was conducted for the first time to summarize the current evidence on the association between miR-31 and OSCC. The vast majority of relevant studies (20/21, 95%) demonstrated that miR-31 was an oncogenic factor in the tumorigenesis and progression of OSCC. miR-31 expression is significantly upregulated in plasma, saliva, and tumor tissue of OSCC. miR-31 played an essential role in OSCC development by constituting a complex network with its targeted genes (e.g. RhoA, FIH, ACOX1, VEGF, SIRT3, LATS2, KANK1, and NUMB) and the signaling cascades (e.g. EGF-AKT signaling axis, ERK-MMP9 cascade, Hippo pathway, Wnt signaling, and MCT1/MCT4 regulatory cascade). This review highlights that miR-31 might function as a potential diagnostic, prognostic, and predictive biomarker for OSCC. Further studies are still warranted to better illuminate the clinicopathological features and the molecular mechanisms of miR-31-mediated OSCC development.

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.

The prognostic role of miR-31 in colorectal cancer: the results of a meta-analysis of 4720 patients

Aims: To study the association between miR-31 expression and clinical outcomes in colorectal cancer. Methods: A systematic search was performed and 16 studies were found eligible. To calculate the combined hazard ratio (HR), the DerSimonian and Laird random-effects model was used. Results: Pooled analysis revealed significant associations between high miR-31 expression and poor overall (HR: 0.68; 95% CI: 0.47-0.97; I²: 68.6%) and progression-free survival (HR: 0.49; 95% CI: 0.33-0.73; I²: 81.1%). High expressers were more likely to have a BRAF mutation. Therapeutic regimen and the mutational status significantly affected the observed associations. Conclusion: We identified that high miR-31 expression is associated with poor overall survival and progression-free survival and has a significant predictive value for anti-EGFR response.

Revealing potential immunotherapy targets through analysis of a ceRNA network in human colon adenocarcinoma

BACKGROUND

Microsatellite instability-high (MSI-H) is a special type of human colon adenocarcinoma (COAD) that responds well to immunotherapy. MicroRNAs (miRNAs) and long non-coding RNAs (lncRNAs), which are important members of competing endogenous RNAs (ceRNAs) networks, are involved in the tumorigenesis and development of MSI-H COAD. This study aimed to establish a ceRNA network for MSI in COAD to identify targets and prognostic markers that may explain the effects of immunotherapy.

METHODS

COAD sequencing data were extracted from The Cancer Genome Atlas (TCGA), after which differentially expressed miRNAs, lncRNAs, and mRNAs were determined according to microsatellite status. After building a network based on the ceRNA hypothesis, the relationships between microsatellite status and clinical features were explored. Biological processes in the Gene Ontology (GO) and the Kyoto Encyclopedia of Genes and Genomes (KEGG) databases were analyzed for specific miRNAs, lncRNAs, and mRNAs. Survival analysis was used to identify potential biomarkers.

RESULTS

Based on the inclusion criteria, a total of 363 COAD samples were obtained from TCGA. Strict screening criteria were used to identify differentially expressed RNAs in the MSI-H and microsatellite-stable groups, with 82 miRNAs, 1,280 lncRNAs, and 2121 mRNAs obtained (fold change >2, false discovery rate <0.01). Based on the RNA interaction mechanism, a miRNA-lncRNA-mRNA network was constructed, through which a subnetwork composed of 5 miRNAs was discovered. hsa-miR-31-5p, hsa-miR-302a-3p, hsa-miR-302b-3p, hsa-miR-302d-3p, hsa-miR-3619-5p and the RNAs interaction with them have the potential to become novel targets to change the effect of existing immunotherapy. GO and KEGG analyses showed that these differentially expressed miRNAs, lncRNAs, and mRNAs may play key roles in tumorigenesis, tumor development, and drug efficacy, with natural killer cells potentially becoming the next emerging targets for immunotherapy enhancement. Moreover, survival analysis identified 10 lncRNAs as potential survival markers.

CONCLUSIONS

This study identified novel immunotherapy targets and revealed potential biomarkers for COAD according to microsatellite status.

A novel tumour suppressor protein encoded by circMAPK14 inhibits progression and metastasis of colorectal cancer by competitively binding to MKK6

BACKGROUND

The mitogen-activated protein kinase (MAPK) pathway is highly associated with the progression and metastasis of various solid tumours. MAPK14, a core molecule of the MAPK pathway, plays vital roles in the colorectal cancer (CRC). Recent studies have shown that circRNAs can affect tumour progression by encoding peptides. However, little is known regarding the potential protein translated from circMAPK14 and whether it plays a role in the carcinogenesis of colorectal cancer.

METHODS

The RNA level and translatable potential of circMAPK14 in CRC was verified using qRT-PCR and public databases. RNase R digestion assay, qRT-PCR, sanger sequencing and FISH assays were utilised to verify the circular characteristics and subcellular localisation of circMAPK14. The suppressive role of circMAPK14 on the progression and metastasis of CRC was verified in vivo and in vitro. LC/MS analysis combined with western blotting demonstrated the presence and relative expression of circMAPK14-175aa. The underlying mechanism of circMAPK14-175aa action to inhibit CRC was identified by co-IP analysis. The binding of U2AF2 within the flanking introns of circMAPK14 was evaluated by RNA pull-down assay and RIP assay. Ultimately, luciferase reporter gene assays and ChIP assays confirmed that FOXC1 suppressed transcription of U2AF2 by binding to the U2AF2 promoter in the -400 bp to -100 bp region.　 RESULTS: We identified that hsa_circ_0131663 (termed circMAPK14) showed significantly decreased expression level in cells and tissue samples of CRC, and was primarily localised in the cytoplasm. A series of function experiments demonstrated that circMAPK14 influenced CRC progression and metastasis by encoding a peptide of 175 amino acids (termed circMAPK14-175aa). We also found that circMAPK14-175aa reduced nuclear translocation of MAPK14 by competitively binding to MKK6, thus facilitating ubiquitin-mediated degradation of FOXC1. Moreover, we described a positive feedback loop in CRC in which elevated FOXC1 expression was caused by reduced circMAPK14-175aa expression. This, in turn, decreased circMAPK14 biogenesis by suppressing U2AF2 transcription.

CONCLUSION

In summary, we reported for the first time that circMAPK14 functioned as a tumour-suppressor by encoding circMAPK14-175aa, which blocked the progression and metastasis of colorectal cancer.

Therapeutically Targeting Cancers That Overexpress FOXC1: A Transcriptional Driver of Cell Plasticity, Partial EMT, and Cancer Metastasis

Metastasis accounts for more than 90% of cancer related mortality, thus the most pressing need in the field of oncology today is the ability to accurately predict future onset of metastatic disease, ideally at the time of initial diagnosis. As opposed to current practice, what would be desirable is that prognostic, biomarker-based detection of metastatic propensity and heightened risk of cancer recurrence be performed long before overt metastasis has set in. Without such timely information it will be impossible to formulate a rational therapeutic treatment plan to favorably alter the trajectory of disease progression. In order to help inform rational selection of targeted therapeutics, any recurrence/metastasis risk prediction strategy must occur with the paired identification of novel prognostic biomarkers and their underlying molecular regulatory mechanisms that help drive cancer recurrence/metastasis (i.e. recurrence biomarkers). Traditional clinical factors alone (such as TNM staging criteria) are no longer adequately prognostic for this purpose in the current molecular era. FOXC1 is a pivotal transcription factor that has been functionally implicated to drive cancer metastasis and has been demonstrated to be an independent predictor of heightened metastatic risk, at the time of initial diagnosis. In this review, we present our viewpoints on the master regulatory role that FOXC1 plays in mediating cancer stem cell traits that include cellular plasticity, partial EMT, treatment resistance, cancer invasion and cancer migration during cancer progression and metastasis. We also highlight potential therapeutic strategies to target cancers that are, or have evolved to become, “transcriptionally addicted” to FOXC1. The potential role of FOXC1 expression status in predicting the efficacy of these identified therapeutic approaches merits evaluation in clinical trials.

WITHDRAWN: FOXC1 modulates stem-like cell properties and chemoresistance through hedgehog and EMT signaling in gastric adenocarcinoma

This article has been withdrawn at the request of the editors. The Publisher apologizes for any inconvenience this may cause. The full Elsevier Policy on Article Withdrawal can be found at http://www.elsevier.com/locate/withdrawalpolicy.

Roles of circRNAs in cancer chemoresistance (Review)

Circular RNA (circRNA) is a type of endogenous, high‑stability, noncoding RNA. circRNAs exhibit various biological functions, and are involved in physiological and pathological processes occurring in various diseases, including cancers. They can not only act as microRNA and protein sponges, but also interact with proteins, translated peptides, and transcriptional and translational regulators, and compete with pre‑mRNA splicing. Chemotherapy is one of the most important types of cancer treatment. However, the resistance of cancer cells to chemotherapy is a leading reason for the failure of chemotherapy. It has been reported that circRNAs play important roles in cancer resistance via a number of mechanisms. The functions of the circRNAs provide insight into their roles in chemoresistance pathways. In addition, some circRNAs may serve as novel biomarkers for the diagnosis and prognosis of cancer resistance. Obtaining improved understanding of the molecular regulatory networks featuring circRNAs in tumors and searching for markers for the diagnosis and treatment of cancer resistance are leading issues in circRNA research. The present review introduced the functions of circRNAs, illustrated the mechanisms underlying drug resistance in cancer, described the contributions of circRNAs to this resistance and discussed the potential application of circRNAs in the treatment of drug‑resistant cancer. In particular, the review aimed to reveal the main mechanisms of circRNAs in cancer drug resistance, including mechanisms involving drug transport and metabolism, alterations of drug targets, DNA damage repair, downstream resistance mechanisms, adaptive responses and the tumor microenvironment. The findings may provide novel therapeutic targets for clinical treatment of cancer chemoresistance.

The Molecular Networks of microRNAs and Their Targets in the Drug Resistance of Colon Carcinoma

Simple Summary

We systematically reviewed the recent scientific publications describing the role of microRNAs in the regulation of drug resistance in colon cancer. To clarify the intricate web of resulting genetic and biochemical interactions, we used a machine learning approach aimed at creating: (i) networks of validated miRNA/target interactions involved in drug resistances and (ii) drug-centric networks, from which we identified the major clusters of proteins affected by drugs used in the treatment of colon cancer. Finally, to facilitate a high-level interpretation of these molecular interactions, we determined the cellular pathways related with drug resistance and regulated by the miRNAs in colon cancer.

Abstract

Drug resistance is one of the major forces driving a poor prognosis during the treatment and progression of human colon carcinomas. The molecular mechanisms that regulate the diverse processes underlying drug resistance are still under debate. MicroRNAs (miRNAs) are a subgroup of non-coding RNAs increasingly found to be associated with the regulation of tumorigenesis and drug resistance. We performed a systematic review of the articles concerning miRNAs and drug resistance in human colon cancer published from 2013 onwards in journals with an impact factor of 5 or higher. First, we built a network with the most studied miRNAs and targets (as nodes) while the drug resistance/s are indicated by the connections (edges); then, we discussed the most relevant miRNA/targets interactions regulated by drugs according to the network topology and statistics. Finally, we considered the drugs as nodes in the network, to allow an alternative point of view that could flow through the treatment options and the associated molecular pathways. A small number of microRNAs and proteins appeared as critically involved in the most common drugs used for the treatment of patients with colon cancer. In particular, the family of miR-200, miR34a, miR-155 and miR-17 appear as the most relevant microRNAs. Thus, regulating these miRNAs could be useful for interfering with some drug resistance mechanisms in colorectal carcinoma.

Arecoline induces heart injure via Fas/Fas ligand apoptotic pathway in heart of Sprague-Dawley rat

Habitual chewing of areca nut increases the risk of cardiovascular disease mortality, but less report demonstrate the toxic mechanism of areca nut on heart. To investigate toxicity of areca nut on cardiomyocytes, we induced the heart injury with arecoline to evaluate the acute damage of areca nut on heart. Different concentrations of are coline (lowdosage: 5 mg/kg/day and high dosage 50 mg/kg/day) were injected into Sprague-Dawley rat via intra-peritoneal method for 21 days to create negative effects of arecoline on cardiomyocyte. Themyocardial architecture of the rat heart was observed. The arecoline-induced apoptotic proteins were analysed via western blotting. The myocardialarchitecture of heart was injured with arecoline and TUNEL stain was also shown are coline-induced cardiac apoptosis. Arecoline promoted the protein expression of both Fas dependent snd mitochondrial dependent apoptosis. In summary, arecoline induces cardiac toxicity and apoptosis by inducing both death receptor and mitochondria-dependent apoptotic pathways on heart.

Exosomes as New Biomarkers and Drug Delivery Tools for the Prevention and Treatment of Various Diseases: Current Perspectives

Exosomes are nano-sized vesicles secreted by most cells that contain a variety of biological molecules, such as lipids, proteins and nucleic acids. They have been recognized as important mediators for long-distance cell-to-cell communication and are involved in a variety of biological processes. Exosomes have unique advantages, positioning them as highly effective drug delivery tools and providing a distinct means of delivering various therapeutic agents to target cells. In addition, as a new clinical diagnostic biomarker, exosomes play an important role in many aspects of human health and disease, including endocrinology, inflammation, cancer, and cardiovascular disease. In this review, we summarize the development of exosome-based drug delivery tools and the validation of novel biomarkers, and illustrate the role of exosomes as therapeutic targets in the prevention and treatment of various diseases.

The Hypoxia-Long Noncoding RNA Interaction in Solid Cancers

Hypoxia is one of the representative microenvironment features in cancer and is considered to be associated with the dismal prognosis of patients. Hypoxia-driven cellular pathways are largely regulated by hypoxia-inducible factors (HIFs) and notably exert influence on the hallmarks of cancer, such as stemness, angiogenesis, invasion, metastasis, and the resistance towards apoptotic cell death and therapeutic resistance; therefore, hypoxia has been considered as a potential hurdle for cancer therapy. Growing evidence has demonstrated that long noncoding RNAs (lncRNAs) are dysregulated in cancer and take part in gene regulatory networks owing to their various modes of action through interacting with proteins and microRNAs. In this review, we focus attention on the relationship between hypoxia/HIFs and lncRNAs, in company with the possibility of lncRNAs as candidate molecules for controlling cancer.

miR-5000-3p confers oxaliplatin resistance by targeting ubiquitin-specific peptidase 49 in colorectal cancer

Colorectal cancer (CRC) is the most common form of gastrointestinal malignancies. A growing number of reports focusing on oxaliplatin (OXA) resistance in CRC treatment have revealed that drug resistance is an urgent issue in clinical applications, especially for finding effective therapeutic targets. Recently, microRNAs (miRNAs) are reported to play a critical role in tumor progressions and multi-drug resistance. The main aim of this study is to establish whether miR-5000-3p is an oncogene that is resistant to OXA and further confirm its underlying regulatory role in CRC. The OXA-associated gene expression dataset in CRC cells was downloaded from Gene Expression Omnibus (GEO) database. Statistical software R was used for significance analysis of differentially expressed genes (DEGs) between OXA-resistant (OR)-CRC cells and CRC cells, and results indicated ubiquitin-specific peptidase 49 (USP49) was upregulated in OR-CRC cells. Luciferase reporter assay showed that USP49 was verified to act as a downstream target gene of miR-5000-3p. From the results of TCGA database, miR-5000-3p expression was upregulated and USP49 was downregulated in patients with CRC. The function of miR-5000-3p was detected using MTT assay, wound healing, Transwell, and flow cytometry assays. Moreover, through in vitro and in vivo experiments, miR-5000-3p expression was confirmed to be upregulated in CRC cells or OR-CRC cells comparing to normal cell lines. Molecular mechanism assays revealed that USP49 binds to the miR-5000-3p promoter to increase the expression of miR-5000-3p, resulting in cancer cells sensitized to OXA. To sum up, these results suggest that miR-5000-3p may be a novel biomarker involved in drug-resistance progression of CRC. Moreover, the drug-resistance mechanism of miR-5000-3p/USP49 axis provides new treatment strategies for CRC in clinical trials.

FOXC1 Negatively Regulates DKK1 Expression to Promote Gastric Cancer Cell Proliferation Through Activation of Wnt Signaling Pathway

Gastric cancer (GC), characterized by uncontrolled growth, is a common malignant tumor of the digestive system. The Wnt signaling pathway plays an important role in the tumorigenesis and proliferation of GC. Many studies on this signaling pathway have focused on its intracellular regulatory mechanism, whereas little attention has been given to extracellular regulatory factors. Dickkopf-1 (Dkk1) is a secretory glycoprotein, and it can bind inhibit activation of the Wnt pathway. However, the regulation and mechanism of DKK1 in the proliferation of GC remain unclear. FOXC1 plays an important role in organ development and tumor growth, but its role in GC tumor growth remains unknown. In this study, we found that the FOXC1 is highly expressed in patients with GC and high expression of FOXC1 correlates to poor prognosis. In addition, we found that the Wnt signaling pathway in GC cells with high FOXC1 expression was strongly activated. FOXC1 negatively regulates DKK1 expression by binding to its promoter region, thereby promoting the activation of Wnt pathway. FOXC1 can also form a complex with unphosphorylated β-catenin protein in the cytoplasm and then dissociates from β-catenin in the nucleus, thereby promoting the entry of β-catenin into the nucleus and regulating expression of c-MYC, which promotes the proliferation of GC cells. Our study not only reveals the function and mechanism of FOXC1 in GC, but also provides a potential target for clinic GC treatment.

Hsa-miR-107 regulates chemosensitivity and inhibits tumor growth in hepatocellular carcinoma cells

Hepatocellular carcinoma is a common type of liver cancer. Resistance to chemotherapeutic agents is a major problem in cancer therapy. MicroRNAs have been reported in cancer development and tumor growth; however, the relationship between chemoresistance and hepatocellular carcinoma needs to be fully investigated. Here, we treated hepatocellular carcinoma cell line (HA22T) with a histone deacetylase inhibitor to establish hepatocellular carcinoma-resistant cells (HDACi-R) and investigated the molecular mechanisms of chemoresistance in HCC cells. Although histone deacetylase inhibitor could not enhance cell death in HDACi-R but upregulation of miR-107 decreased cell viability both in parental cells and resistance cells, decreased the expression of cofilin-1, enhanced ROS-induced cell apoptosis, and dose-dependently sensitized HDACi-R to HDACi. Further, miR-107 upregulation resulted in tumor cell disorganization in both HA22T and HDACi-R in a mice xenograft model. Our findings demonstrated that miR-107 downregulation leads to hepatocellular carcinoma cell resistance in HDACi via a cofilin-1-dependent molecular mechanism and ROS accumulation.

miR-122-5p Mediates Fluoride-Induced Osteoblast Activation by Targeting CDK4

Chronic intake of fluoride, existing in the environment, may cause endemic fluorosis, which is characterized by the occurrence of skeletal and dental fluorosis. However, the pathogenesis of fluorosis has not yet been elucidated. Abnormal osteoblast proliferation and activation have a pivotal role in bone turnover disorders which are linked to skeletal fluorosis. MicroRNAs are involved in fundamental cellular processes, including cell proliferation. Based on our previous study, population study and in vitro experiments were designed to understand the effect of miR-122-5p on osteoblast activation in skeletal fluorosis through targeting cyclin-dependent kinase 4 (CDK4). In human populations with coal-burning type fluoride exposure, the results showed that miR-122-5p was downregulated but CDK4 expression was upregulated and miR-122-5p was negatively correlated with CDK4 expression. Furthermore, in human osteoblasts treated with sodium fluoride, we demonstrated that miR-122-5p mediated osteoblast activation of skeletal fluorosis via upregulation of the CDK4 protein. In support of this, dual-luciferase reporter assay showed that miR-122-5p modulated CDK4 protein levels by targeting its 3'-untranslated region. These findings show, for the first time, that miR-122-5p may be involved in the cause and development of skeletal fluorosis by targeting CDK4.

Inhibitory effect of miR-140-5p on doxorubicin resistance of hepatocellular carcinoma

To investigate the role of microRNA (miR)-140-5p in doxorubicin (DOX) sensitivity in hepatocellular carcinoma, miR-140-5p and peptidyl-prolyl cis-trans isomerase NIMA-interacting 1 (PIN1) expression was first evaluated in hepatocellular carcinoma tissues using starBase. Next, in vitro experiments were performed. Cell line expression of miR-140-5p and PIN1 expression was detected by reverse transcription polymerase chain reaction. Cell viability and proliferation were determined by the Cell Counting Kit-8 and EdU assays. The relationship between miR-140-5p and PIN1 was evaluated by TargetScan and a luciferase reporter system. Western blotting was used to detect the expression of PIN1. It was observed that miR-140-5p was downregulated in hepatocellular carcinoma tissues and cell lines compared with normal samples in HCC or normal liver cells. Gain-of-function experiments revealed that miR-140-5p mimics were able to enhance DOX sensitivity of hepatocellular carcinoma cells. Further studies revealed that PIN1 was a target gene of miR-140-5p. Suppression of PIN1 led to higher DOX sensitivity in hepatocellular carcinoma cells. Finally, when comparing a PIN1-siRNA alone group and a PIN1-siRNA plus miR-140-5p inhibitor group, there was no significant difference in cell viability. Furthermore, miR-140-5p mimics did not reduce the sensitivity of PIN1mut plasmid to DOX in HUH7 and SNU449 cells. The present study demonstrated that miR-140-5p could enhance DOX sensitivity in hepatocellular carcinoma cells by targeting PIN1.

Emerging roles of dehydrogenase/reductase member 2 (DHRS2) in the pathology of disease

Dehydrogenase/reductase member 2 (DHRS2) belongs to the short-chain dehydrogenase/reductase (SDR) family. It was initially isolated from the nuclear extract of hepatocellular carcinoma HepG2 cells and was identified as a specific cell cycle regulator. DHRS2 is a reduced nicotinamide adenine dinucleotide phosphate (NADPH)-dependent carbonyl reductase and catalyzes the reduction of dicarbonyl compounds. It is also functionally active in lipid metabolism and acts as a metabolic enzyme of hormones. Recent studies have shown that DHRS2 reprograms lipid metabolism and redox homeostasis to regulate proliferation, migration, invasion, and drug resistance of cancer cells. Here, we describe the structure, organelle localization and function of DHRS2, and also highlight its roles in the pathologic progression of diseases.

Portrait of Cancer Stem Cells on Colorectal Cancer: Molecular Biomarkers, Signaling Pathways and miRNAome

Colorectal cancer (CRC) is a leading cause of cancer death worldwide, and about 20% is metastatic at diagnosis and untreatable. Increasing evidence suggests that the heterogeneous nature of CRC is related to colorectal cancer stem cells (CCSCs), a small cells population with stemness behaviors and responsible for tumor progression, recurrence, and therapy resistance. Growing knowledge of stem cells (SCs) biology has rapidly improved uncovering the molecular mechanisms and possible crosstalk/feedback loops between signaling pathways that directly influence intestinal homeostasis and tumorigenesis. The generation of CCSCs is probably connected to genetic changes in members of signaling pathways, which control self-renewal and pluripotency in SCs and then establish function and phenotype of CCSCs. Particularly, various deregulated CCSC-related miRNAs have been reported to modulate stemness features, controlling CCSCs functions such as regulation of cell cycle genes expression, epithelial-mesenchymal transition, metastasization, and drug-resistance mechanisms. Primarily, CCSC-related miRNAs work by regulating mainly signal pathways known to be involved in CCSCs biology. This review intends to summarize the epigenetic findings linked to miRNAome in the maintenance and regulation of CCSCs, including their relationships with different signaling pathways, which should help to identify specific diagnostic, prognostic, and predictive biomarkers for CRC, but also develop innovative CCSCs-targeted therapies.

Hyperglycemia-Induced Cardiac Damage Is Alleviated by Heat-Inactivated Lactobacillus reuteri GMNL-263 via Activation of the IGF1R Survival Pathway

Diabetes-induced cardiomyocyte apoptosis is one of the major causes of mortality in patients with diabetes. Numerous studies have indicated the beneficial effects of Lactobacillus reuteri GMNL-263. However, the protective effect of Lactobacillus reuteri GMNL-263 in cardiac damage associated with diabetes remains poorly understood. In this study, we aimed to investigate the protective effect of Lactobacillus reuteri GMNL-263 on cardiomyocytes in diabetic rats. Five-week-old male Wistar rats were categorized into normal control group, diabetes group (55 mg/kgw STZ-induced diabetes via intraperitoneal injection), and diabetic animals treated with Lactobacillus reuteri GMNL-263 (10⁹ CFU/rat/day, oral administration for 4 weeks). The results were presented that oral administration of a high dose of Lactobacillus reuteri GMNL-263 in diabetic rats activated IGF1R cell survival pathways to decrease the Fas-dependent and mitochondrial-dependent apoptotic pathways induced by hyperglycemia. We found that GMNL-263 significantly attenuated cell apoptosis via the IGF1R survival pathway in diabetic rats. The findings of this study suggest that GMNL-263 treatment maybe an effective therapeutic approach for the prevention of cardiac apoptosis in patients with diabetes.

Platycodin D reverses histone deacetylase inhibitor resistance in hepatocellular carcinoma cells by repressing ERK1/2-mediated cofilin-1 phosphorylation

BACKGROUND

Chemoresistance remains the main obstacle in hepatocellular carcinoma (HCC) therapy. Despite significant advances in HCC therapy, HCC still has a poor prognosis. Thus, there is an urgent need to identify a treatment target to reverse HCC chemotherapy resistance. Platycodon grandiflorus (PG) is a perennial herb that has been used as food and traditional Chinese medicine for thousands of years in Northeast Asia. Platycodin D (PD), a main active triterpenoid saponin found in the root of PG, has been reported to possess anticancer properties in several cancer cell lines, including HCC; however, the reversal effect of this molecule on HCC chemoresistance remains largely unknown.

PURPOSE

This study aimed to investigate the role and the mechanism of PD-mediated reversal of the histone deacetylase inhibitor (HDACi) resistance in HCC cells.

METHODS

Human HCC cells (HA22T) and HDACi-resistant (HDACi-R) cells were used. Cell viability was measured using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Combination index was used to calculate the synergism potential. Expression of ERK1/2 (total/phospho), cofilin-1 (total/phospho) and apoptosis-related protein was determined using western blotting. Mitochondrial membrane potential was assessed using the JC-1 (5,5',6,6'-tetrachloro-1,1',3,3'-tetraethylbenzimidazolocarbocyanine iodide) probe. Apoptosis was detected using the terminal deoxynucleotidyl transferase dUTP nick end labeling assay. Mitochondrial reactive oxygen species generation was measured using the MitoSOX Red fluorescent probe.

RESULTS

We found that PD treatment inhibited cell viability both in HA22T HCC and HDACi-R cells. Inhibition of ERK1/2 by PD98059 could reverse drug resistance in HDACi-R cells treated with PD98059 and PD. Nevertheless, pre-treatment with U46619, an ERK1/2 activator, rescued PD-induced apoptosis by decreasing levels of apoptosis-related proteins in HCC cells. The combined treatment of PD with apicidin a powerful HDACi, dramatically enhanced the apoptotic effect in HDACi-R cells.

CONCLUSION

For the first time, we showed that PD reversed HDACi resistance in HCC by repressing ERK1/2-mediated cofilin-1 phosphorylation. Thus, PD can potentially be a treatment target to reverse HCC chemotherapy resistance in future therapeutic trials.

Calmodulin/CaMKII-γ mediates prosurvival capability in apicidin-persistent hepatocellular carcinoma cells via ERK1/2/CREB/c-fos signaling pathway

Calmodulin (CaM), a Ca²⁺ binding protein, plays a critical role in cancer initiation and progression through binding and activating numerous target proteins, including Ca²⁺ /calmodulin-dependent protein kinase (CaMK) family proteins. However, the mechanisms underlying the effects of CaM/CaMKs on the survival capability of liver cancer cells is unclear, and this study investigates this mechanism in apicidin-persistent HA22T cells. CaM level was upregulated, especially in the cytosol, in apicidin-persistent HA22T cells than in parental HA22T cells and was positively associated with cell proliferation and migration capacity of apicidin-persistent HA22T cells. Further, the expression of CaM-activated CaMKs-dependent signaling cascades, including CaMKK2, CaMKIV, CaMKII-γ, and p-CaMKII was observed in apicidin-persistent HA22T cells, which were transiently activated by mitogen-activated protein kinase oncogenic signaling, such as CREB, ERK1/2, and c-fos. Furthermore, a specific CaM inhibitor trifluoperazine reduced the levels of p-CREB, p-ERK1/2, and c-fos in apicidin-persistent HA22T cells than in parental HA22T cells. Additionally, inhibition of CaM also suppressed CaM-induced Bcl-XL (an antiapoptotic protein) expression in apicidin-persistent HA22T cells. Our finding emphasizes an essential role of CaM/CaMKs in augmentation of the survival capability of apicidin-persistent liver cancer cells and suggests that CaM inhibition significantly attenuates CaM-induced tumor growth and abrogates antiapoptotic function and also offers a promising therapeutic target for cancer treatment.

Long non-coding RNA LINC00525 interacts with miR-31-5p and miR-125a-5p to act as an oncogenic molecule in spinal chordoma

LINC00525 is a new-researched long non-coding RNA (lncRNA) in a few cancers. This study aims at researching the function of LINC00525 in spinal chordoma and the underlying mechanism of action. LINC00525, microRNA-31-5p (miR-31-5p) and microRNA-125a-5p (miR-125a-5p) detection was performed by quantitative real-time polymerase chain reaction (qRT-PCR). We found the high expression of LINC00525 but the low levels of miR-31-5p and miR-125a-5p in spinal chordoma tissues. After LINC00525 was downregulated in spinal chordoma cells, there were inhibitory effects on cell proliferation, migration, invasion and EMT but a promoting effect on cell apoptosis. MiR-31-5p and miR-125a-5p were the downstream targets of LINC00525. The function of LINC00525 knockdown in spinal chordoma cells were achieved by upregulating miR-31-5p and miR-125a-5p. Tumorigenesis of spinal chordoma in vivo was also inhibited by knockdown of LINC00525 via the promotion of miR-31-5p and miR-125a-5p. All these results suggested that LINC00525 targeted miR-31-5p and miR-125a-5p to promote the tumorigenesis and progression of spinal chordoma. LINC00525 can be a novel molecular target in spinal chordoma.

Regulation of Hippo signaling pathway in cancer: A MicroRNA perspective

Recent studies have suggested that Hippo signaling is not only involved in controlling organ size in Drosophila but can also regulate cell proliferation, tissue homeostasis, differentiation, apoptosis and regeneration. Any dysregulation of Hippo signaling, especially the hyper activation of its downstream effectors YAP/TAZ, can lead to uncontrolled cell proliferation and malignant transformation. In majority of cancers, expression of YAP/TAZ is extremely high and this increased expression of YAP/TAZ has been shown to be an independent predictor of prognosis and indicator of increased cell proliferation, metastasis and poor survival. In this review, we have summarized the most recent findings about the cross talk of Hippo signaling pathway with other signaling pathways and its regulation by different miRNAs in various cancer types. Recent evidence has suggested that Hippo pathway is also involved in mediating the resistance of different cancer cells to chemotherapeutic drugs and in a few cancer types, this is brought about by regulating miRNAs. Therefore, the delineation of the underlying mechanisms regulating the chemotherapeutic resistance might help in developing better treatment options. This review has attempted to provide an overview of different drugs/options which can be utilized to target oncogenic YAP/TAZ proteins for therapeutic interventions.

MicroRNAs: Multifaceted Regulators of Colorectal Cancer Metastasis and Clinical Applications

Colorectal cancer (CRC) is the third-commonest malignant cancer, and its metastasis is the major reason for cancer-related death. The process of metastasis is highly coordinated and involves a complex cascade of multiple steps. In recent years, miRNAs, as highly conserved, endogenous, noncoding, single-stranded RNA, has been confirmed to be involved in the development of various cancers. Considering that miRNA is also involved in a series of biological behaviors, regulating CRC occurrence and development, we review and summarize the role of miRNAs and related signaling pathways in several CRC-metastasis stages, including invasion and migration, mobility, metabolism, epithelial–mesenchymal transition, tumor-microenvironment communication, angiogenesis, anoikis, premetastatic–niche formation, and cancer stemness. In addition, we review the application of miRNAs as diagnostic CRC markers and in clinical treatment resistance. This review can contribute to understanding of the mechanism of miRNAs in CRC progression and provide a theoretical basis for clinical CRC treatment.