GDPD5, a target of miR-195-5p, is associated with metastasis and chemoresistance in colorectal cancer

PRKDC Induces Chemoresistance in Osteosarcoma by Recruiting GDE2 to Stabilize GNAS and Activate AKT

Chemoresistance is one of the major causes of poor prognosis in osteosarcoma. Alternative therapeutic strategies for osteosarcoma are limited, indicating that increasing sensitivity to currently used chemotherapies could be an effective approach to improve patient outcomes. Using a kinome-wide CRISPR screen, we identified PRKDC as a critical determinant of doxorubicin (DOX) sensitivity in osteosarcoma. The analysis of clinical samples demonstrated that PRKDC was hyperactivated in osteosarcoma, and functional experiments showed that the loss of PRKDC significantly increased sensitivity of osteosarcoma to DOX. Mechanistically, PRKDC recruited and bound GDE2 to enhance the stability of protein GNAS. The elevated GNAS protein levels subsequently activated AKT phosphorylation and conferred resistance to DOX. The PRKDC inhibitor AZD7648 and DOX synergized and strongly suppressed the growth of osteosarcoma in mouse xenograft models and human organoids. In conclusion, the PRKDC-GDE2-GNAS-AKT regulatory axis suppresses DOX sensitivity and comprises targetable candidates for improving the efficacy of chemotherapy in osteosarcoma. Significance: Targeting PRKDC suppresses AKT activation and increases sensitivity to doxorubicin in osteosarcoma, which provides a therapeutic strategy for overcoming chemoresistance.

Research status and potential applications of circRNAs affecting colorectal cancer by regulating ferroptosis

Ferroptosis is an emerging form of non-apoptotic programmed cell death (PCD), characterized by iron-mediated oxidative imbalance. This process plays a significant role in the development and progression of various tumors, including colorectal cancer, gastric cancer, and others. Circular RNA (circRNA) is a stable, non-coding RNA type with a single-stranded, covalently closed loop structure, which is intricately linked to the proliferation, invasion, and metastasis of tumor cells. Recent studies have shown that many circRNAs regulate various pathways leading to cellular ferroptosis. Colorectal cancer, known for its high incidence and mortality among cancers, is marked by a poor prognosis and pronounced chemoresistance. To enhance our understanding of how circRNA-mediated regulation of ferroptosis influences colorectal cancer development, this review systematically examines the mechanisms by which specific circRNAs regulate ferroptosis and their critical role in the progression of colorectal cancer. Furthermore, it explores the potential of circRNAs as biomarkers and therapeutic targets in colorectal cancer treatment, offering a novel approach to clinical management.

Exploring the impact of MiR-92a-3p on FOLFOX chemoresistance biomarker genes in colon cancer cell lines

Introduction: One of the primary obstacles faced by individuals with advanced colorectal cancer (CRC) is the potential development of acquired chemoresistance as the disease advances. Studies have indicated a direct association between elevated levels of miR-92a-3p and the progression, metastasis, and chemoresistance observed in CRC. We proposed that miR-92a-3p impairs FOLFOX (fluorouracil/oxaliplatin) chemotherapy response by upregulating the expression of chemoresistance biomarker genes through the activation of β-catenin and epithelial-mesenchymal transition (EMT). These FOLFOX biomarker genes include the pyrimidine biosynthesis pathway genes dihydropyrimidine dehydrogenase (DPYD), thymidylate synthase (TYMS), methylenetetrahydrofolate reductase (MTHFR), and the genes encoding the DNA repair complexes subunits ERCC1 and ERCC2, and XRCC1. Methods: To assess this, we transfected SW480 and SW620 colon cancer cell lines with miR-92a-3p mimics and then quantified the expression of DPYD, TYMS, MTHFR, ERCC1, ERCC2, and XRCC1, the expression of EMT markers and transcription factors, and activation of β-catenin. Results and discussion: Our results reveal that miR-92a-3p does not affect the expression of DPYD, TYMS, MTHFR, and ERCC1. Furthermore, even though miR-92a-3p affects ERCC2, XRCC1, E-cadherin, and β-catenin mRNA levels, it has no influence on their protein expression. Conclusion: We found that miR-92a-3p does not upregulate the expression of proteins of DNA-repair pathways and other genes involved in FOLFOX chemotherapy resistance.

The Critical Function of microRNAs in Developing Resistance against 5- Fluorouracil in Cancer Cells

Although there have been significant advancements in cancer treatment, resistance and recurrence in patients make it one of the leading causes of death worldwide. 5-fluorouracil (5-FU), an antimetabolite agent, is widely used in treating a broad range of human malignancies. The cytotoxic effects of 5-FU are mediated by the inhibition of thymidylate synthase (TYMS/TS), resulting in the suppression of essential biosynthetic activity, as well as the misincorporation of its metabolites into RNA and DNA. Despite its huge benefits in cancer therapy, the application of 5-FU in the clinic is restricted due to the occurrence of drug resistance. MicroRNAs (miRNAs) are small, non-coding RNAs that act as negative regulators in many gene expression processes. Research has shown that changes in miRNA play a role in cancer progression and drug resistance. This review examines the role of miRNAs in 5-FU drug resistance in cancers.

An epigenetic modulator with promising therapeutic impacts against gastrointestinal cancers: A mechanistic review on microRNA-195

Due to their high prevalence, gastrointestinal cancers are one of the key causes of cancer-related death globally. The development of drug-resistant cancer cell populations is a major factor in the high mortality rate, and it affects about half of all cancer patients. Because of advances in our understanding of cancer molecular biology, non-coding RNAs (ncRNAs) have emerged as critical factors in the initiation and development of gastrointestinal cancers. Gene expression can be controlled in several ways by ncRNAs, including through epigenetic changes, interactions between microRNAs (miRNAs) and long non-coding RNAs (lncRNAs) and proteins, and the function of lncRNAs as miRNA precursors or pseudogenes. As lncRNAs may be detected in the blood, circulating ncRNAs have emerged as a promising new class of non-invasive cancer biomarkers for use in the detection, staging, and prognosis of gastrointestinal cancers, as well as in the prediction of therapy efficacy. In this review, we assessed the role lncRNAs play in the progression, and maintenance of colorectal cancer, and how they might be used as therapeutic targets in the future.

Unraveling the function of epithelial-mesenchymal transition (EMT) in colorectal cancer: Metastasis, therapy response, and revisiting molecular pathways

Colorectal cancer (CRC) is a dangerous form of cancer that affects the gastrointestinal tract. It is a major global health concern, and the aggressive behavior of tumor cells makes it difficult to treat, leading to poor survival rates for patients. One major challenge in treating CRC is the metastasis, or spread, of the cancer, which is a major cause of death. In order to improve the prognosis for patients with CRC, it is necessary to focus on ways to inhibit the cancer's ability to invade and spread. Epithelial-mesenchymal transition (EMT) is a process that is linked to the spread of cancer cells, also known as metastasis. The process transforms epithelial cells into mesenchymal ones, increasing their mobility and ability to invade other tissues. This has been shown to be a key mechanism in the progression of colorectal cancer (CRC), a particularly aggressive form of gastrointestinal cancer. The activation of EMT leads to increases in the spread of CRC cells, and during this process, levels of the protein E-cadherin decrease while levels of N-cadherin and vimentin increase. EMT also contributes to the development of resistance to chemotherapy and radiation therapy in CRC. Non-coding RNAs, such as long non-coding RNAs (lncRNAs) and circular RNAs (circRNAs), play a role in regulating EMT in CRC, often through their ability to "sponge" microRNAs. Anti-cancer agents have been shown to suppress EMT and reduce the progression and spread of CRC cells. These findings suggest that targeting EMT or related mechanisms may be a promising approach for treating CRC patients in the clinic.

IGF2BP3 Worsens Lung Cancer through Modifying Long Non-coding RNA CERS6-AS1/microRNA-1202 Axis

BACKGROUND

Insulin-like growth factor 2 mRNA-binding protein 3 (IGF2BP3) can epigenetically regulate lung cancer progression, but its regulatory mechanism in the disease lacks sufficient exploration.

OBJECTIVE

The study was conducted to probe the regulatory function of IGF2BP3 in lung cancer via modulating the long non-coding RNA CERS6-AS1/microRNA-1202 (CERS6- AS1/miR-1202) axis.

METHODS

Clinical samples were collected to evaluate IGF2BP3, CERS6-AS1, miR-1202 and glycerophosphodiester phosphodiesterase domain containing 5 (GDPD5) levels. The interactions among IGF2BP3, CERS6-AS1, miR-1202 and GDPD5 were assessed. IGF2BP3-, CERS6-AS1-, and miR-1202-related constructs were transfected into lung cancer cells to determine cell biological functions. Cell tumor formation ability was further detected in vivo.

RESULTS

High expression of IGF2BP3, CERS6-AS1 and GDPD5, and low expression of miR-1202 levels were witnessed in lung cancer tissues. Suppression of IGF2BP3 restrained lung cancer progression. IGF2BP3 positively modulated CERS6-AS1 to regulate miR-1202-targeted GDPD5. Inhibition of CERS6-AS1 or promotion of miR-1202 depressed lung cancer aggravation. CERS6-AS1 silencing or miR-1202 overexpression reversed the impacts induced by IGF2BP3 on lung cancer.

CONCLUSION

IGF2BP3 facilitates the development of lung cancer cells via binding to the CERS6-AS1 promoter and down-regulating miR-1202, which may be related to GDPD5 upregulation.

Novel strategies to reverse chemoresistance in colorectal cancer

Colorectal cancer (CRC) is a common gastrointestinal malignancy with high morbidity and fatality. Chemotherapy, as traditional therapy for CRC, has exerted well antitumor effect and greatly improved the survival of CRC patients. Nevertheless, chemoresistance is one of the major problems during chemotherapy for CRC and significantly limits the efficacy of the treatment and influences the prognosis of patients. To overcome chemoresistance in CRC, many strategies are being investigated. Here, we review the common and novel measures to combat the resistance, including drug repurposing (nonsteroidal anti-inflammatory drugs, metformin, dichloroacetate, enalapril, ivermectin, bazedoxifene, melatonin, and S-adenosylmethionine), gene therapy (ribozymes, RNAi, CRISPR/Cas9, epigenetic therapy, antisense oligonucleotides, and noncoding RNAs), protein inhibitor (EFGR inhibitor, S1PR2 inhibitor, and DNA methyltransferase inhibitor), natural herbal compounds (polyphenols, terpenoids, quinones, alkaloids, and sterols), new drug delivery system (nanocarriers, liposomes, exosomes, and hydrogels), and combination therapy. These common or novel strategies for the reversal of chemoresistance promise to improve the treatment of CRC.

Publication trends and hotspots of drug resistance in colorectal cancer during 2002-2021: A bibliometric and visualized analysis

Background

Chemotherapy, radiotherapy, targeted therapy and immunotherapy have demonstrated expected clinical efficacy, while drug resistance remains the predominant limiting factor to therapeutic failure in patients with colorectal cancer (CRC). Although there have been numerous basic and clinical studies on CRC resistance in recent years, few publications utilized the bibliometric method to evaluate this field. The objective of current study was to provide a comprehensive analysis of the current state and changing trends of drug resistance in CRC over the past 20 years.

Methods

The Web of Science Core Collection (WOSCC) was utilized to extracted all studies regarding drug resistance in CRC during 2002-2021. CiteSpace and online platform of bibliometrics were used to evaluate the contributions of various countries/regions, institutions, authors and journals in this field. Moreover, the recent research hotspots and promising future trends were identified through keywords analysis by CiteSpace and VOSviewer.

Results

1451 related publications from 2002 to 2021 in total were identified and collected. The number of global publications in this field has increased annually. China and the USA occupied the top two places with respect to the number of publications, contributing more than 60% of global publications. Sun Yat-sen University and Oncotarget were the institution and journal which published the most papers, respectively. Bardelli A from Italy was the most prolific writer and had the highest H-index. Keywords burst analysis identified that “Growth factor receptor”, “induced apoptosis” and “panitumumab” were the ones with higher burst strength in the early stage of this field. Analysis of keyword emergence time showed that “oxaliplatin resistance”, “MicroRNA” and “epithelial mesenchymal transition (EMT)” were the keywords with later average appearing year (AAY).

Conclusions

The number of publications and research interest on drug resistance in CRC have been increasing annually. The USA and China were the main driver and professor Bardelli A was the most outstanding researcher in this field. Previous studies have mainly concentrated on growth factor receptor and induced apoptosis. Oxaliplatin resistance, microRNA and EMT as recently appeared frontiers of research that should be closely tracked in the future.

Identification of miR-195-5p as a novel prognostic biomarker for colorectal cancer

BACKGROUND

Recent evidence indicated that transcription patterns of microRNAs could be used as promising biomarkers for numerous cancers. It is stated that miR-195-5p could be used as a tumor suppressor in colorectal cancer (CRC). The purpose of the current work was to explore the transcription level of miR-195-5p and its clinical relevance in CRC patients.

METHODS AND RESULTS

We used quantitative real-time polymerase chain reaction (qRT-PCR) to assess the tumor tissue sample of 140 CRC cases compared with normal adjacent tissue for the transcription of miR-195-5p and the clinicopathological relevance was statistically evaluated. We showed that tumor tissue miR-195-5p transcription was statistically downregulated in patients with CRC (median expression value 0.23, range 0.03-6.62) compared to normal adjacent tissue (median expression value 0.98, range 0.092-29.6, p < 0.001). The median transcription of miR-195-5p divided the CRC patients into miR-195-5p low-transcription (miR-195-5plow) and miR-195-5p high-transcription (miR-195-5phigh) groups. Furthermore, low miR-195-5p transcription level was statistically related with TNM stage, lymph node metastasis and tumor differentiation in CRC patients (all p-value < 0.05). Moreover, our results indicated that CRC cases with a decreased transcription level of miR-195-5p displayed a statistically shorter overall survival (OS) (p = 0.001) compared to higher miR-195-5p transcription.

CONCLUSION

In conclusion, the finding proposes that miR-195-5p might be a valuable biomarker and a prognostic factor for CRC in the future.

Roles and mechanisms of miR-195-5p in human solid cancers

Cancer persists as a worldwide disease that contributes to high morbidity and mortality rates. As a class of non-coding RNA, microRNAs (miRNAs) are one kind of important regulators in cancer and frequently implicated in tumor development and progression. Emerging experiments have suggested that miRNA-195-5p (miR-195-5p) can regulate neoplastic processes in many pathways. For instance, miR-195-5p can not only regulate proliferation, migration and invasion of tumor cells but also promote tumor cell apoptosis. Furthermore, low expression of miR-195-5p could induce drug resistance. Our review focuses on the expression of miR-195-5p in various tumors and elucidates the related mechanisms of which miR-195-5p participates in tumor biology, as well as summarizes the roles of miR-195-5p in tumor progression. We believe that miR-195-5p might have potential utility as a novel diagnostic biomarker and therapeutic target for cancer.

Circulating microRNAs as molecular biomarkers for lung adenocarcinoma

BACKGROUND: The potential of microRNAs (miRNAs) as molecular tumor biomarkers for early diagnosis and prognosis in lung cancer is still unclear. OBJECTIVE: To analyze expression of miRNAs in A549 lung adenocarcinoma (LUAD) cells and in primary, non-malignant bronchial epithelial (BE) cells from healthy donors. To analyze the most prominently deregulated miRNAs in plasma samples of LUAD patients and healthy donors. MATERIALS AND METHODS: The expression of 752 miRNAs in LUAD and BE cells was assessed by RT-qPCR with mean-centering restricted normalization. The relative plasma levels of 18 miRNAs in LUAD patients and healthy donors were analyzed using RT-qPCR and normalized to miR-191-5p and miR-16-3p. Putative interactions between miRNAs and their target genes were investigated in silico. RESULTS: Out of 752 miRNAs, 37 miRNAs were significantly deregulated in A549 cells compared to BE cells. MiR-15b-3p, miR-148a-3p, miR-193b-3p, and miR-195-5p were significantly deregulated in plasma samples of LUAD patients compared to donors. The target genes of those four miRNAs are involved in essential mechanisms in cancer development and progression. CONCLUSIONS: There are substantial differences between cancer and control miRNA expression in vitro and in plasma samples of LUAD patients compared to healthy donors. Four deregulated miRNAs are promising as a diagnostic biomarker for adenocarcinoma of the lung.

RNA-Seq profiling of circular RNAs in human colorectal cancer 5-fluorouracil resistance and potential biomarkers

BACKGROUND

Colorectal cancer (CRC) is a commonly diagnosed cancer of the digestive system worldwide. Although chemotherapeutic agents and targeted therapeutic drugs are currently available for CRC treatment, drug resistance is a problem that cannot be ignored and needs to be solved.

AIM

To explore the relationship between circular RNA (circRNA) and CRC drug resistance. circRNA plays a key role in the occurrence and development of cancers, but its function in the process of drug resistance has not been widely revealed.

METHODS

To explore the role of circRNA in 5-fluorouracil (5-Fu) resistance, we performed the circRNA expression profile in two CRC cell lines and their homologous 5-Fu resistant cells by high-throughput sequencing.

RESULTS

We validated the differentially expressed circRNAs in other two paired CRC cells, confirmed that circ_0002813 and circ_0000236 could have a potential competitive endogenous RNA mechanism and be involved in the formation of 5-Fu resistance. And we combined the sequencing results of mRNA to construct the regulatory network of circRNA-miRNA-mRNA.

CONCLUSION

Our study revealed that circ_0002813 and circ_0000236 may as the biomarkers to predict the occurrence of 5-Fu resistance in CRC.

MicroRNAs and 'Sponging' Competitive Endogenous RNAs Dysregulated in Colorectal Cancer: Potential as Noninvasive Biomarkers and Therapeutic Targets

The gastrointestinal (GI) tract in mammals is comprised of dozens of cell types with varied functions, structures, and histological locations that respond in a myriad of ways to epigenetic and genetic factors, environmental cues, diet, and microbiota. The homeostatic functioning of these cells contained within this complex organ system has been shown to be highly regulated by the effect of microRNAs (miRNA). Multiple efforts have uncovered that these miRNAs are often tightly influential in either the suppression or overexpression of inflammatory, apoptotic, and differentiation-related genes and proteins in a variety of cell types in colorectal cancer (CRC). The early detection of CRC and other GI cancers can be difficult, attributable to the invasive nature of prophylactic colonoscopies. Additionally, the levels of miRNAs associated with CRC in biofluids can be contradictory and, therefore, must be considered in the context of other inhibiting competitive endogenous RNAs (ceRNA) such as lncRNAs and circRNAs. There is now a high demand for disease treatments and noninvasive screenings such as testing for bloodborne or fecal miRNAs and their inhibitors/targets. The breadth of this review encompasses current literature on well-established CRC-related miRNAs and the possibilities for their use as biomarkers in the diagnoses of this potentially fatal GI cancer.

MicroRNAs and Heat Shock Proteins in Breast Cancer Biology

Breast cancer has five major immune types; luminal A, luminal B, HER2, Basal-like, and normal-like. Cells produce a family of protein called heat shock proteins (Hsps) in response to exposure to thermal and other proteotoxic stresses play essential roles in cancer metabolism and this large family shows a diverse set of Hsp involvement in different breast cancer immune types. Recently, Hsp members categorized according to their immune type roles. Hsp family consists of several subtypes formed by molecular weight; Hsp70, Hsp90, Hsp100, Hsp40, Hsp60, and small molecule Hsps. Cancer cells employ Hsps as survival factors since most of these proteins prevent apoptosis. Several studies monitored Hsp roles in breast cancer cells and reported Hsp27 involvement in drug resistance, Hsp70 in tumor cell transformation-progression, and interaction with p53. Furthermore, the association of Hsp90 with steroid receptors and signaling proteins in patients with breast cancer directed research to focus on Hsp-based treatments. miRNAs are known to play key roles in all types of cancer that are upregulated or downregulated in cancer which respectively referred to as oncogenes (oncomirs) or tumor suppressors. Expression profiles of miRNAs may be used to classify, diagnose, and predict different cancer types. It is clear that miRNAs play regulatory roles in gene expression and this work reveals miRNA correlation to Hsp depending on specific breast cancer immune types. Deregulation of specific Hsp genes in breast cancer subtypes allows for identification of new targets for drug design and cancer treatment. Here, we performed miRNA network analysis by recruiting Hsp genes detected in breast cancer subtypes and reviewed some of the miRNAs related to aforementioned Hsp genes.

Identification of a Five-Gene Signature Derived From MYCN Amplification and Establishment of a Nomogram for Predicting the Prognosis of Neuroblastoma

Background: Neuroblastoma (NB), the most common solid tumor in children, exhibits vastly different genomic abnormalities and clinical behaviors. While significant progress has been made on the research of relations between clinical manifestations and genetic abnormalities, it remains a major challenge to predict the prognosis of patients to facilitate personalized treatments. Materials and Methods: Six data sets of gene expression and related clinical data were downloaded from the Gene Expression Omnibus (GEO) database, ArrayExpress database, and Therapeutically Applicable Research to Generate Effective Treatments (TARGET) database. According to the presence or absence of MYCN amplification, patients were divided into two groups. Differentially expressed genes (DEGs) were identified between the two groups. Enrichment analyses of these DEGs were performed to dig further into the molecular mechanism of NB. Stepwise Cox regression analyses were used to establish a five-gene prognostic signature whose predictive performance was further evaluated by external validation. Multivariate Cox regression analyses were used to explore independent prognostic factors for NB. The relevance of immunity was evaluated by using algorithms, and a nomogram was constructed. Results: A five-gene signature comprising CPLX3, GDPD5, SPAG6, NXPH1, and AHI1 was established. The five-gene signature had good performance in predicting survival and was demonstrated to be superior to International Neuroblastoma Staging System (INSS) staging and the MYCN amplification status. Finally, a nomogram based on the five-gene signature was established, and its clinical efficacy was demonstrated. Conclusion: Collectively, our study developed a novel five-gene signature and successfully built a prognostic nomogram that accurately predicted survival in NB. The findings presented here could help to stratify patients into subgroups and determine the optimal individualized therapy.

Effects of MicroRNA-195-5p on Biological Behaviors and Radiosensitivity of Lung Adenocarcinoma Cells via Targeting HOXA10

Objective

To explore the effects of miR-195-5p and its target gene HOXA10 on the biological behaviors and radiosensitivity of lung adenocarcinoma (LUAD) cells.

Methods

The effects of miR-195-5p on LUAD cell proliferation, migration, invasion, cycle arrest, apoptosis, and radiosensitivity were investigated by in vitro experiments. The bioinformatics analysis was used to assess its clinical value and predict target genes. Double-luciferase experiments were used to verify whether the miR-195-5p directly targeted HOXA10. A xenograft tumor-bearing mouse model was used to examine its effects on the radiosensitivity of LUAD in vivo.

Results

Both gain- and loss-of-function assays demonstrated that miR-195-5p inhibited LUAD cell proliferation, invasion, and migration, induced G1 phase arrest and apoptosis, and enhanced radiosensitivity. Double-luciferase experiments confirmed that miR-195-5p directly targeted HOXA10. Downregulation of HOXA10 also inhibited LUAD cell proliferation, migration, and invasion, induced G1 phase arrest and apoptosis, and enhanced radiosensitivity. The protein levels of β-catenin, c-myc, and Wnt1 were decreased by miR-195-5p and increased by its inhibitor. Moreover, the effects of the miR-195-5p inhibitor could be eliminated by HOXA10-siRNA. Furthermore, miR-195-5p improved radiosensitivity of LUAD cells in vivo.

Conclusion

miR-195-5p has excellent antitumor effects via inhibiting cancer cell growth, invasion, and migration, arresting the cell cycle, promoting apoptosis, and sensitizing LUAD cells to X-ray irradiation by targeting HOXA10. Thus, miR-195-5p may serve as a potential candidate for the treatment of LUAD.

The role of non-coding RNAs in chemotherapy for gastrointestinal cancers

Gastrointestinal (GI) cancers, including colorectal, gastric, hepatic, esophageal, and pancreatic tumors, are responsible for large numbers of deaths around the world. Chemotherapy is the most common approach used to treat advanced GI cancer. However, chemoresistance has emerged as a critical challenge that prevents successful tumor elimination, leading to metastasis and recurrence. Chemoresistance mechanisms are complex, and many factors and pathways are involved. Among these factors, non-coding RNAs (ncRNAs) are critical regulators of GI tumor development and subsequently can induce resistance to chemotherapy. This occurs because ncRNAs can target multiple signaling pathways, affect downstream genes, and modulate proliferation, apoptosis, tumor cell migration, and autophagy. ncRNAs can also induce cancer stem cell features and affect the epithelial-mesenchymal transition. Thus, ncRNAs could possibly act as new targets in chemotherapy combinations to treat GI cancer and to predict treatment response.

MiR-195-5p represses inflammation, apoptosis, oxidative stress, and endoplasmic reticulum stress in sepsis-induced myocardial injury by targeting activating transcription factor 6

Myocardial injury (MI) is a common complication of sepsis. MicroRNAs (miRNAs) have been suggested as potential biomarkers of MI; however, their mechanisms in sepsis-induced MI remain unclear. A sepsis rat model was constructed by use of cecal ligation and puncture (CLP). The levels of miR-195-5p and activating transcription factor 6 (ATF6) expression were determined by quantitative reverse-transcription polymerase chain reaction, and cytokine levels were detected by ELISA. The levels of oxidative stress (OS)-related indicators and endoplasmic reticulum stress (ERS)-related proteins were examined, and the regulatory effect of miR-195-5p on ATF6 was determined by using the luciferase reporter assay. Our results showed that miR-195-5p expression was downregulated and ATF6 expression was upregulated in lipopolysaccharide-induced cardiomyocytes and mice with CLP-induced sepsis. We also found that miR-195-5p could markedly attenuate the inflammation, apoptosis, OS, and ERS associated with sepsis-induced MI. Additionally, we verified that miR-195-5p could relieve sepsis-induced MI by targeting ATF6. This study identified potential targets for treating MI after sepsis.

CircRASSF2 facilitates the proliferation and metastasis of colorectal cancer by mediating the activity of Wnt/β-catenin signaling pathway by regulating the miR-195-5p/FZD4 axis

Circular RNAs (circRNA) are a key regulator of cancer progression, including colorectal cancer (CRC). Nevertheless, the role of circRASSF2 in CRC remains unclear. Quantitative real-time PCR was used to measure the expression of circRASSF2 and miR-195-5p. Cell counting kit 8 assay, colony formation assay, flow cytometry and transwell assay were used to determine the proliferation, apoptosis, migration and invasion of cells, respectively. The levels of proliferation, metastasis and Wnt/β-catenin signaling pathway-related proteins, as well as Frizzled 4 (FZD4) protein, were determined using western blot analysis. Furthermore, a dual-luciferase reporter assay, RNA immunoprecipitation assay and RNA pull-down assay were used to illumine the mechanism of circRASSF2. Animal experiments were used to determine the role of circRASSF2 in the tumor growth of CRC in vivo. Our study reported that circRASSF2 was upregulated in CRC tissues and cells, and its high expression was related to the poor prognosis of CRC patients. CircRASSF2 knockdown could inhibit proliferation, migration, invasion, and enhance apoptosis in CRC cells, and its overexpression had the opposite effect. Besides, our data revealed that circRASSF2 could sponge miR-195-5p, and miR-195-5p could target FZD4. The rescue experiments indicated that both miR-195-5p inhibitor and FZD4 overexpression could reverse the negative regulation of circRASSF2 silencing on CRC progression. Moreover, circRASSF2 could positively regulate the activity of Wnt/β-catenin signaling pathway by the miR-195-5p/FZD4 axis. In addition, circRASSF2 knockdown restrained the tumor growth of CRC in vivo. Our findings suggested that circRASSF2 might function as a tumor promoter to accelerate the progression of CRC via regulating the miR-195-5p/FZD4/Wnt/β-catenin pathway.

MicroRNA-195-5p suppresses the proliferation, migration, invasion and epithelial-mesenchymal transition of laryngeal cancer cells in vitro by targeting E2F3

Increasing evidence has indicated that microRNAs (miRNAs/miRs) play an important role in the occurrence and development of various types of cancer. The aim of the present study was to investigate the role and underlying molecular mechanisms of miR-195-5p in laryngeal cancer cell proliferation, migration and invasion. Reverse transcription-quantitative PCR (RT-qPCR) was performed to measure the expression levels of miR-195-5p in laryngeal carcinoma cell lines. The expression levels of miR-195-5p and E2F transcription factor 3 (E2F3) were modified by transfection with miR-195-5p mimics and pcDNA3.1-E2F3. A luciferase reporter assay was used to verify the association between miR-195a-5p and E2F3. Cell Counting Kit-8, cell wound healing and Transwell invasion assays were used to detect the biological functions of laryngeal cancer cells. The expression of epithelial-mesenchymal transition (EMT)-associated genes was evaluated by western blotting and RT-qPCR. The results revealed that the expression of miR-195-5p was decreased in laryngeal cancer cell lines. The overexpression of miR-195-5p inhibited the proliferation, migration, invasion and EMT of laryngeal cancer cells. Dual-luciferase reporter assays revealed that miR-195-5p could directly target E2F3 and that there was a negative association between them. E2F3 overexpression significantly attenuated the inhibitory effects of the overexpression of miR-195-5p on the proliferation, migration, invasion and EMT of laryngeal cancer cells. Collectively, the findings of the present study demonstrated that the overexpression of miR-195-5p significantly inhibited the progression of laryngeal cancer cells, and these effects may be mediated via the downregulation of the expression of E2F3.

Formononetin relieves the facilitating effect of lncRNA AFAP1-AS1-miR-195/miR-545 axis on progression and chemo-resistance of triple-negative breast cancer

This investigation attempted to discern whether formononetin restrained progression of triple-negative breast cancer (TNBC) by blocking lncRNA AFAP1-AS1-miR-195/miR-545 axis. We prepared TNBC cell lines (i.e. MDA-MB-231 and BT-549) and normal human mammary epithelial cell line (i.e. MCF-10A) in advance, and the TNBC cell lines were, respectively, transfected by pcDNA3.1-lncRNA AFAP1-AS1, si-lncRNA AFAP1-AS1, pcDNA6.2/GW/EmGFP-miR-545 or pcDNA6.2/GW/EmGFP-miR-195. Resistance of TNBC cells in response to 5-Fu, adriamycin, paclitaxel and cisplatin was evaluated through MTT assay, while potentials of TNBC cells in proliferation, migration and invasion were assessed via CCK8 assay and Transwell assay. Consequently, silencing of lncRNA AFAP1-AS1 impaired chemo-resistance, proliferation, migration and invasion of TNBC cells (P<0.05), and over-expression of miR-195 and miR-545, which were sponged and down-regulated by lncRNA AFAP1-AS1 (P<0.05), significantly reversed the promoting effect of pcDNA3.1-lncRNA AFAP1-AS1 on proliferation, migration, invasion and chemo-resistance of TNBC cells (P<0.05). Furthermore, CDK4 and Raf-1, essential biomarkers of TNBC progression, were, respectively, subjected to target and down-regulation of miR-545 and miR-195 (P<0.05), and they were promoted by pcDNA3.1-lncRNA AFAP1-AS1 at protein and mRNA levels (P<0.05). Additionally, formononetin significantly decreased expressions of lncRNA AFAP1-AS1, CDK4 and Raf-1, while raised miR-195 and miR-545 expressions in TNBC cells (P<0.05), and exposure to it dramatically contained malignant behaviors of TNBC cells (P<0.05). In conclusion, formononetin alleviated TNBC malignancy by suppressing lncRNA AFAP1-AS1-miR-195/miR-545 axis, suggesting that molecular targets combined with traditional Chinese medicine could yield significant clinical benefits in TNBC.

Circ_0007142 downregulates miR-874-3p-mediated GDPD5 on colorectal cancer cells

BACKGROUND

Ferroptosis is an iron-dependent and oxidative cell death form. Recent studies suggested that circular RNAs (circRNAs) regulated ferroptosis in tumour cells. Circ_0007142 was identified as a carcinogenic molecule in colorectal cancer (CRC), but its function on ferroptosis in CRC remains unknown.

METHODS

Circ_0007142, microRNA-874-3p (miR-874-3p) and glycerophosphodiester phosphodiesterase domain containing 5 (GDPD5) levels were assayed using the quantitative real-time polymerase chain reaction (qRT-PCR). Cell survival and proliferation were measured by Cell Counting Kit-8 (CCK-8) assay. Protein detection was performed by Western blot. Cell apoptosis was analysed by flow cytometry. Ferroptosis was assessed by iron accumulation and oxidative stress. Target binding was evaluated by dual-luciferase reporter assay. In vivo research was conducted by tumour xenograft in mice.

RESULTS

Circ_0007142 was overexpressed in CRC. After expression inhibition of circ_0007142, proliferation was reduced, while apoptosis and ferroptosis were facilitated in CRC cells. Mechanically, circ_0007142 was found as a miR-874-3p sponge and miR-874-3p inhibitor eliminated the regulation of si-circ_0007142 in CRC cells. MiR-874-3p targeted GDPD5 and upregulation of GDPD5 reversed the miR-874-3p-triggered tumour inhibition and ferroptosis promotion in CRC cells. Moreover, GDPD5 was regulated by the circ_0007142/miR-874-3p axis. Circ_0007142 also affected CRC tumorigenesis in vivo through the regulation of miR-874-3p and GDPD5.

CONCLUSION

All these findings proved that circ_0007142/miR-874-3p/GDPD5 axis regulated tumorigenesis and ferroptosis of CRC cells. Circ_0007142 might be an available marker for ferroptosis in CRC therapy.

5-Fluorouracil: A Narrative Review on the Role of Regulatory Mechanisms in Driving Resistance to This Chemotherapeutic Agent

5-fluorouracil (5-FU) is among the mostly administrated chemotherapeutic agents for a wide variety of neoplasms. Non-coding RNAs have a central impact on the determination of the response of patients to 5-FU. These transcripts via modulation of cancer-related pathways, cell apoptosis, autophagy, epithelial-mesenchymal transition, and other aspects of cell behavior can affect cell response to 5-FU. Modulation of expression levels of microRNAs or long non-coding RNAs may be a suitable approach to sensitize tumor cells to 5-FU treatment via modulating multiple biological signaling pathways such as Hippo/YAP, Wnt/β-catenin, Hedgehog, NF-kB, and Notch cascades. Moreover, there is an increasing interest in targeting these transcripts in various kinds of cancers that are treated by 5-FU. In the present article, we provide a review of the function of non-coding transcripts in the modulation of response of neoplastic cells to 5-FU.

Differential roles of miR-15a/16-1 and miR-497/195 clusters in immune cell development and homeostasis

MicroRNAs (miRNAs) post-transcriptionally repress almost all genes in mammals and thereby form an additional layer of gene regulation. As such, miRNAs impact on nearly every physiological process and have also been associated with cancer. Prominent examples of such miRNAs can be found in the miR-15 family, composed of the bicistronic clusters miR-15a/16-1, miR-15b/16-2, and miR-497/195. In particular, the miR-15a/16-1 cluster is deleted in almost two thirds of all chronic B lymphocytic leukemia (CLL) cases, a phenotype that is also recapitulated by miR-15a/16-1-deficient as well as miR-15b/16-2-deficient mice. Under physiological conditions, those two clusters have been implicated in T-cell function, and B-cell and natural killer (NK) cell development; however, it is unclear whether miR-497 and miR-195 confer similar roles in health and disease. Here, we have generated a conditional mouse model for tissue-specific deletion of miR-497 and miR-195. While mice lacking miR-15a/16-1 in the hematopoietic compartment developed clear signs of CLL over time, aging mice deficient for miR-497/195 did not show such a phenotype. Likewise, loss of miR-15a/16-1 impaired NK and early B-cell development, whereas miR-497/195 was dispensable for these processes. In fact, a detailed analysis of miR-497/195-deficient mice did not reveal any effect on steady-state hematopoiesis or immune cell function. Unexpectedly, even whole-body deletion of the cluster was well-tolerated and had no obvious impact on embryonic development or healthy life span. Therefore, we postulate that the miR-497/195 cluster is redundant to its paralog clusters or that its functional relevance is restricted to certain physiological and pathological conditions.

Novel insights for lncRNA MAGI2-AS3 in solid tumors

Long non-coding RNAs (lncRNAs) refer to elements of genomic transcription with more than 200 nucleotides that are not translated into proteins, but have crucial roles in cancer progression. MAGI2-AS3, a novel lncRNA, has been reported to be aberrantly expressed in many solid tumors. Increasingly, studies have demonstrated that MAGI2-AS3 expression is significantly correlated with patient clinical characteristics, and that MAGI2-AS3 can regulate multiple biological processes through target-gene regulation. Furthermore, MAGI2-AS3 may serve as both a diagnostic biomarker and as a promising therapeutic target against solid tumors. In this review, we summarize the current knowledge regarding the biological functions and related molecular mechanisms of MAGI2-AS3 in solid-tumor progression. We conclude that understanding MAGI2-AS3 properties may provide new insights into the diagnoses and treatments of solid tumors.

MiR-195-5p inhibits proliferation and invasion of nerve cells in Hirschsprung disease by targeting GFRA4

Studies have reported that miR-195-5p plays a role in the Hirschsprung disease (HSCR). Our previous work found GDNF family receptor alpha 4 (GFRA4) is also associated with HSCR. In this study, we focused on whether miR-195-5p induces the absence of enteric neurons and enteric neural crest in HSCR by regulating GFRA4. The expression levels of GFRA4 and miR-195-5p in colon tissues were evaluated by real-time PCR (RT-PCR) assay. We overexpressed GFRA4 or miR-195-5p in SH-SY5Y cells, the cell proliferation, cell cycle, apoptosis and invasion were subsequently investigated by CCK-8 assay, EdU staining, Flow cytometry analysis and Transwell assay, respectively. We also established the xenograft model to detect the effect of miR-195-5p on tumor growth and GFRA4 and p-RET expressions. GFRA4 expression was significantly downregulated in the HSCR colon tissues when compared with that in the control tissues. Overexpression of GFRA4 significantly promoted proliferation, invasion and cell cycle arrest, and inhibited apoptosis of SH-SY5Y cells. We also proved that GFRA4 is a direct target of miR-195-5p, and miR-195-5p inhibited proliferation, invasion, cell cycle arrest and differentiation, and accelerated apoptosis in SH-SY5Y cells which can be reversed by GFRA4 overexpression. Furthermore, we demonstrated that miR-195-5p suppressed tumor growth, and observably decreased GFRA4 and p-RET expressions. Our findings suggest that miR-195-5p plays an important role in the pathogenesis of HSCR. MiR-195-5p inhibited proliferation, invasion and cell cycle arrest, and accelerated apoptosis of nerve cells by targeting GFRA4.

EMT-associated microRNAs and their roles in cancer stemness and drug resistance

Epithelial‐to‐mesenchymal transition (EMT) is implicated in a wide array of malignant behaviors of cancers, including proliferation, invasion, and metastasis. Most notably, previou studies have indicated that both cancer stem‐like properties and drug resistance were associated with EMT. Furthermore, microRNAs (miRNAs) play a pivotal role in the regulation of EMT phenotype, as a result, some miRNAs impact cancer stemness and drug resistance. Therefore, understanding the relationship between EMT‐associated miRNAs and cancer stemness/drug resistance is beneficial to both basic research and clinical treatment. In this review, we preliminarily looked into the various roles that the EMT‐associated miRNAs play in the stem‐like nature of malignant cells. Then, we reviewed the interaction between EMT‐associated miRNAs and the drug‐resistant complex signaling pathways of multiple cancers including lung cancer, gastric cancer, gynecologic cancer, breast cancer, liver cancer, colorectal cancer, pancreatic cancer, esophageal cancer, and nasopharyngeal cancer. We finally discussed the relationship between EMT, cancer stemness, and drug resistance, as well as looked forward to the potential applications of miRNA therapy for malignant tumors.

Epithelial-Mesenchymal Transition and MicroRNAs in Colorectal Cancer Chemoresistance to FOLFOX

The FOLFOX scheme, based on the association of 5-fluorouracil and oxaliplatin, is the most frequently indicated chemotherapy scheme for patients diagnosed with metastatic colorectal cancer. Nevertheless, development of chemoresistance is one of the major challenges associated with this disease. It has been reported that epithelial-mesenchymal transition (EMT) is implicated in microRNA-driven modulation of tumor cells response to 5-fluorouracil and oxaliplatin. Moreover, from pharmacogenomic research, it is known that overexpression of genes encoding dihydropyrimidine dehydrogenase (DPYD), thymidylate synthase (TYMS), methylenetetrahydrofolate reductase (MTHFR), the DNA repair enzymes ERCC1, ERCC2, and XRCC1, and the phase 2 enzyme GSTP1 impair the response to FOLFOX. It has been observed that EMT is associated with overexpression of DPYD, TYMS, ERCC1, and GSTP1. In this review, we investigated the role of miRNAs as EMT promotors in tumor cells, and its potential effect on the upregulation of DPYD, TYMS, MTHFR, ERCC1, ERCC2, XRCC1, and GSTP1 expression, which would lead to resistance of CRC tumor cells to 5-fluorouracil and oxaliplatin. This constitutes a potential mechanism of epigenetic regulation involved in late-onset of acquired resistance in mCRC patients under FOLFOX chemotherapy. Expression of these biomarker microRNAs could serve as tools for personalized medicine, and as potential therapeutic targets in the future.

Circ_ZFR contributes to the paclitaxel resistance and progression of non-small cell lung cancer by upregulating KPNA4 through sponging miR-195-5p

Background

A growing body of evidence has demonstrated the vital roles of circular RNAs (circRNAs) in cancer progression and drug resistance. We intended to explore the roles and mechanisms of circ_ZFR in the paclitaxel (PTX) resistance and progression of non-small cell lung cancer (NSCLC).

Methods

Two NSCLC cell lines A549 and H460 were used in this study. Quantitative real-time polymerase chain reaction (qRT-PCR) assay was conducted to measure the levels of circ_ZFR, ZFR, miR-195-5p and karyopherin subunit alpha 4 (KPNA4) mRNA. RNase R assay was used to analyze the characteristic of circ_ZFR. MTT assay was carried out to assess PTX resistance and cell proliferation. Flow cytometry analysis was utilized to analyze cell cycle and apoptosis. Transwell assay was used to examine cell migration and invasion. Western blot assay was conducted to measure the protein levels of Ki67, Twist1, E-cadherin and KPNA4. Dual-luciferase reporter assay was adopted to verify the combination between miR-195-5p and circ_ZFR or KPNA4. Murine xenograft model assay was used to investigate the effect of circ_ZFR on PTX resistance of NSCLC in vivo.

Results

Circ_ZFR level was enhanced in PTX-resistant NSCLC tissues and cells. Knockdown of circ_ZFR suppressed PTX resistance, cell cycle process, proliferation, migration and invasion and induced apoptosis in PTX-resistant NSCLC cells. For mechanism analysis, circ_ZFR knockdown markedly downregulated the expression of KPNA4 by sponging miR-195-5p, thereby promoting PTX sensitivity and suppressing cell progression in PTX-resistant NSCLC cells. In addition, circ_ZFR silencing enhanced PTX sensitivity of NSCLC in vivo.

Conclusion

Circ_ZFR knockdown played a positive role in overcoming PTX resistance of NSCLC via regulating miR-195-5p/KPNA4 axis, which might provide a possible circRNA-targeted therapy for NSCLC.

miR-195-5p Suppresses Lung Cancer Cell Proliferation, Migration, and Invasion Via FOXK1

Lung cancer remains one of the leading causes of cancer deaths around the world. Previous studies have shown that microRNAs have pivotal functions in tumorigenesis including lung cancer. It is reported that microRNA-195-5p acts as a tumor suppressor role in human cancers. However, the function and molecular mechanism of microRNA-195-5p in lung cancer progression is still unclear. In the present study, the results showed that the expression of microRNA-195-5p was downregulated both in lung cancer tissues and in lung cancer cell lines. Enhanced expression of microRNA-195-5p inhibited cell proliferation, migration, and invasion in lung cancer cells. Furthermore, Forkhead box k1 was identified as the direct target of microRNA-195-5p. Forkhead box k1 overexpression could restore the repressed cell proliferation and metastasis caused by microRNA-195-5p overexpression. Our results demonstrated that a functional mechanism of microRNA-195-5p in regulating lung cancer. It indicates that microRNA-195-5p may regulate lung cancer growth and metastasis through the regulation of Forkhead box k1, highlighting the potential application for the treatment of lung cancer in the future.

MicroRNAs and colorectal cancer chemoresistance: New solution for old problem

BACKGROUND

Colorectal cancer (CRC) is one of the most common gastrointestinal malignancies with a significant mortality rate. Despite the great advances in cancer treatment in the last few decades, effective treatment of CRC is still under challenge. One of the main problems associated with CRC treatment is the resistance of cancer cells to chemotherapy drugs.

METHODS

Many studies have been carried out to identify CRC chemoresistance mechanisms, and shed light on the role of ATP-binding cassette transporters (ABC transporters), enzymes as thymidylate synthase, some signaling pathways, and cancer stem cells (CSC) in chemoresistance and failed CRC chemotherapies. Other studies have also been recently carried out to find solutions to overcome chemoresistance. Some of these studies have identified the role of miRNAs in chemoresistance of the CRC cells and the effective use of these micro-molecules to CRC treatment.

RESULTS

Considering the results of these studies, more focus on miRNAs likely leads to a proper solution to overcome CRC chemoresistance.

CONCLUSION

The current study has reviewed the related literature while discussing the efficacy of miRNAs as potential clinical tools for overcoming CRC chemoresistance and reviewing the most important chemoresistance mechanisms in CRC cells.

ZFAS1 Promotes Cisplatin Resistance via Suppressing miR-421 Expression in Oral Squamous Cell Carcinoma

Purpose

Oral squamous cell carcinoma (OSCC), with high incidence and mortality, represents one of the main reasons for head and neck malignant tumors. We want to investigate the effect of ZFAS1 on DDP resistance in oral squamous cell carcinoma.

Methods

The proliferation and migration of cells was detected by CCK-8 and Transwell assay. The apoptosis was measured by flow cytometry and Western blot. The interaction of ZFAS1, miR-421, and MEIS2 was verified by luciferase reporter assay. The role of ZFAS1 in DDP resistance in vivo was tested by the nude mice model. The expression of ZFAS1 in exosomes from cisplatin-resistant patients was also determined.

Results

ZFAS1 overexpression improved OSCC cell growth and inhibited OSCC cell susceptibility to DDP. In addition, the silencing of ZFAS1 promoted DDP-induced apoptosis. ZFAS1 directly bound to miR-421, which was verified by luciferase reporter assay. Inhibition of miR-421 reversed the effect of si-ZFAS1, which promoted the cell viability and decreased the sensitivity of DDP in DDP-resistant cells. The in vivo experiment showed the role of ZFAS1 in increasing the DDP resistance in OSCC tumor. Importantly, this study also showed upregulated ZFAS1 in serum exosomes derived from cisplatin-resistant patients.

Conclusion

ZFAS1 promotes chemoresistance of oral squamous cell carcinoma to cisplatin and might become a latent therapeutic target for treating OSCC.

miRNA Clusters with Down-Regulated Expression in Human Colorectal Cancer and Their Regulation

Regulation of microRNA (miRNA) expression has been extensively studied with respect to colorectal cancer (CRC), since CRC is one of the leading causes of cancer mortality worldwide. Transcriptional control of miRNAs creating clusters can be, to some extent, estimated from cluster position on a chromosome. Levels of miRNAs are also controlled by miRNAs "sponging" by long non-coding RNAs (ncRNAs). Both types of miRNA regulation strongly influence their function. We focused on clusters of miRNAs found to be down-regulated in CRC, containing miR-1, let-7, miR-15, miR-16, miR-99, miR-100, miR-125, miR-133, miR-143, miR-145, miR-192, miR-194, miR-195, miR-206, miR-215, miR-302, miR-367 and miR-497 and analysed their genome position, regulation and functions. Only evidence provided with the use of CRC in vivo and/or in vitro models was taken into consideration. Comprehensive research revealed that down-regulated miRNA clusters in CRC are mostly located in a gene intron and, in a majority of cases, miRNA clusters possess cluster-specific transcriptional regulation. For all selected clusters, regulation mediated by long ncRNA was experimentally demonstrated in CRC, at least in one cluster member. Oncostatic functions were predominantly linked with the reviewed miRNAs, and their high expression was usually associated with better survival. These findings implicate the potential of down-regulated clusters in CRC to become promising multi-targets for therapeutic manipulation.

Propofol Reduces Epithelial to Mesenchymal Transition, Invasion and Migration of Gastric Cancer Cells through the MicroRNA-195-5p/Snail Axis

BACKGROUND Gastric cancer (GC) is a life-threating malignancy worldwide. Accumulating studies suggest propofol has anti-tumor functions in addition to the anesthetic effect. This study aimed to figure out the effects of propofol treatment in GC development. MATERIAL AND METHODS Human GC SGC-7901 and NCI-N87 cells were treated with different doses of propofol. Then the invasion and migration of GC cells was measured. SGC-7901 cells following 10 μM propofol treatment were applied in the following experiments. MicroRNAs (miRNAs) with differential expression in cells with or without propofol treatment were analyzed. Expression of miR-195-5p, Snail, vimentin and E-cadherin in SGC-7901 cells was measured, and then loss-of-function of miR-195-5p and gain-of-function of Snail were performed. Target relation between miR-195-5p and Snail was confirmed using luciferase assay. Xenograft tumor was induced in nude mice to identify the effect of propofol on GC in vivo. RESULTS Propofol reduced epithelial to mesenchymal transition (EMT), invasion and migration of GC cells in a dose-dependent manner. Propofol elevated miR-195-5p expression but reduced Snail expression, and it reduced vimentin but increased E-cadherin expression in SGC-7901 cells. miR-195-5p directly bound to Snail. miR-195-5p inhibition or Snail promotion reversed propofol-inhibited malignant behaviors of SGC-7901 cells. In vitro results were reproduced in in vivo experiments. CONCLUSIONS Our study found that propofol could inhibit EMT, invasion, and migration of GC cells by promoting miR-195-5p expression and suppressing Snail expression. This study may provide novel insights in GC treatment.

Role of non-coding RNAs and RNA modifiers in cancer therapy resistance

As the standard treatments for cancer, chemotherapy and radiotherapy have been widely applied to clinical practice worldwide. However, the resistance to cancer therapies is a major challenge in clinics and scientific research, resulting in tumor recurrence and metastasis. The mechanisms of therapy resistance are complicated and result from multiple factors. Among them, non-coding RNAs (ncRNAs), along with their modifiers, have been investigated to play key roles in regulating tumor development and mediating therapy resistance within various cancers, such as hepatocellular carcinoma, breast cancer, lung cancer, gastric cancer, etc. In this review, we attempt to elucidate the mechanisms underlying ncRNA/modifier-modulated resistance to chemotherapy and radiotherapy, providing some therapeutic potential points for future cancer treatment.

Angioregulatory microRNAs in Colorectal Cancer

Colorectal cancer (CRC) is one of the leading causes of cancer mortality. Angiogenesis is a rate-determining step in CRC development and metastasis. The balance of angiogenic and antiangiogenic factors is crucial in this process. Angiogenesis-related genes can be regulated post-transcriptionally by microRNAs (miRNAs) and some miRNAs have been shown to shuttle between tumor cells and the tumor microenvironment (TME). MiRNAs have context-dependent actions and can promote or suppress angiogenesis dependent on the type of cancer. On the one hand, miRNAs downregulate anti-angiogenic targets and lead to angiogenesis induction. Tumor suppressor miRNAs, on the other hand, enhance anti-angiogenic response by targeting pro-angiogenic factors. Understanding the interaction between these miRNAs and their target mRNAs will help to unravel molecular mechanisms involved in CRC progression. The aim of this article is to review the current literature on angioregulatory miRNAs in CRC.

MiR-195-5p Inhibits Proliferation and Induces Apoptosis of Non-Small Cell Lung Cancer Cells by Targeting CEP55

Objective

This study aims to explore whether miR-195-5p can inhibit proliferation and induce apoptosis of non-small cell lung cancer (NSCLC) cells by targeting CEP55.

Methods

qRT-PCR was used to measure the expression of miR-195-5p in NSCLC cells. MTT assay, colony formation assay, and flow cytometry were used to detect the role of miR-195-5p in NSCLC cells. Western blot was used to measure the protein expression of CEP55, Bax and Bcl-2 in cells. Dual-Luciferase assay was performed to verify the relationship between miR-195-5p and CEP55.

Results

The expression of miR-195-5p was higher in human normal lung cell lines than in NSCLC cells. MiR-195-5p overexpression inhibited cell proliferation, which could block the cell cycle of A549 cell line in the G₀/G₁ phase. Moreover, overexpression of miR-195-5p increased cell apoptotic rate of A549 cell lines, with the expression of pro-apoptotic protein Bax up-regulated and that of the anti-apoptotic protein Bcl-2 down-regulated. The Dual-Luciferase assay showed that miR-195-5p could specifically target CEP55. Furthermore, CEP55 was down-regulated in NSCLC cells. Overexpression of CEP55 enhanced the proliferation and colony formation ability of A549 cell line. Overexpression of CEP55 can reverse the inhibitory effect of miR-195-5p.

Conclusion

MiR-195-5p inhibits proliferation and induces apoptosis of NSCLC cells by negatively regulating CEP55.

Focus on the glycerophosphocholine pathway in choline phospholipid metabolism of cancer

Activated choline metabolism is a hallmark of carcinogenesis and tumor progression, which leads to elevated levels of phosphocholine and glycerophosphocholine in all types of cancer tested so far. Magnetic resonance spectroscopy applications have played a key role in detecting these elevated choline phospholipid metabolites. To date, the majority of cancer-related studies have focused on phosphocholine and the Kennedy pathway, which constitutes the biosynthesis pathway for membrane phosphatidylcholine. Fewer and more recent studies have reported on the importance of glycerophosphocholine in cancer. In this review article, we summarize the recent literature on glycerophosphocholine metabolism with respect to its cancer biology and its detection by magnetic resonance spectroscopy applications.

Proteomic Analysis of miR-195 and miR-497 Replacement Reveals Potential Candidates that Increase Sensitivity to Oxaliplatin in MSI/P53wt Colorectal Cancer Cells

Most patients with advanced colorectal cancer (CRC) eventually develop resistance to systemic combination therapy. miR-195-5p and miR-497-5p are downregulated in CRC tissues and associated with drug resistance. Sensitization to 5-FU, oxaliplatin, and irinotecan by transfection with miR-195-5p and miR-497-5p mimics was studied using cell viability and clonogenic assays in cell lines HCT116, RKO, DLD-1, and SW480. In addition, proteomic analysis of transfected cells was implemented to identify potential targets. Significantly altered proteins were subjected to STRING (protein-protein interaction networks) database analysis to study the potential mechanisms of drug resistance. Cell viability analysis of transfected cells revealed increased sensitivity to oxaliplatin in microsatellite instable (MSI)/P53 wild-type HCT116 and RKO cells. HCT116 transfected cells formed significantly fewer colonies when treated with oxaliplatin. In sensitized cells, proteomic analysis showed 158 and 202 proteins with significantly altered expression after transfection with miR-195-5p and miR-497-5p mimics respectively, of which CHUK and LUZP1 proved to be coinciding downregulated proteins. Resistance mechanisms of these proteins may be associated with nuclear factor kappa-B signaling and G1 cell-cycle arrest. In conclusion, miR-195-5p and miR-497-5p replacement enhanced sensitivity to oxaliplatin in treatment naïve MSI/P53 wild-type CRC cells. Proteomic analysis revealed potential miRNA targets associated with the cell-cycle which possibly bare a relation with chemotherapy sensitivity.

Overexpression of microRNA-195-5p reduces cisplatin resistance and angiogenesis in ovarian cancer by inhibiting the PSAT1-dependent GSK3β/β-catenin signaling pathway

Background

Ovarian cancer (OC) is one of the leading causes for cancer-related deaths among women. MicroRNAs (miRs) have been proved to be vital to the development and progression of OC. Hence, the study aims to evaluate the ability of miR-195-5p affecting cisplatin (DDP) resistance and angiogenesis in OC and the underlying mechanism.

Methods

MiRs that could target phosphoserine aminotransferase 1 (PSAT1), a differentially expressed gene in OC, were predicted by miRNA-mRNA prediction websites. The expression patterns of miR-195-5p in the OC tissues and cells were determined using RNA quantification assay. The role of miR-195-5p in OC was evaluated by determining DDP resistance, apoptosis and angiogenesis of OC cells after up-regulating or down-regulating miR-195-5p or PSAT1, or blocking the glycogen synthase kinase-3β (GSK3β)/β-catenin signaling pathway. Animal experiment was conducted to explore the effect of miR-195-5p on resistance to DDP and angiogenesis.

Result

MiR-195-5p directly targeted PSAT1 and down-regulated its expression. The expression of miR-195-5p was lower while that of PSAT1 was higher in OC tissues than in adjacent normal tissues. When miR-195-5p was over-expressed or PSAT1 was silenced, the expression of HIF-1α, VEGF, PSAT1, β-catenin as well as the extent of GSK3β phosphorylation was reduced, the angiogenesis and resistance to DDP was diminished and apoptosis was promoted both in vitro and in vivo. The inhibition of GSK3β/β-catenin signaling pathway was involved in the regulation process.

Conclusion

Over-expression of miR-195-5p reduced angiogenesis and DDP resistance in OC, which provides a potential therapeutic target for the treatment of OC.

Clinical value of combined detection of miR-1202 and miR-195 in early diagnosis of cervical cancer

The clinical value of the combined detection of miR-1202 and miR-195 in the early diagnosis of cervical cancer was studied. A retrospective analysis of 70 cervical cancer patients treated in the The Third Affiliated Hospital of Kunming Medical University and Yunnan Cancer Hospital from October 2015 to December 2017 was performed, and the lesion tissues were used as the experimental group. Normal cervical tissues from another 67 healthy females confirmed by physical examination at the same period were selected as the control group. The FIGO staging criteria were used for staging of the cervical cancer patients, reverse transcription-quantitative polymerase chain reaction (RT-qPCR) method was used for the detection of the expression of miR-1202 and miR-195 in different tissues, and the receiver operating curve (ROC) was used for the analysis of the application values of miR-1202 and miR-195 diagnosis alone and their combined diagnosis in early cervical cancer patients. The levels of miR-1202 and miR-195 in the experimental group were lower than those in the control group (P<0.05). The differences were significant in the different stages of cervical cancer tissues (P<0.05). The later the staging of cervical cancer tissues were, the lower the levels of miR-1202 and miR-195 were. The sensitivities and area under the curve (AUC) values of miR-1202 and miR-195 in the combined diagnosis of early cervical cancer were significantly higher than those of miR-1202 and miR-195 alone. The expression levels of miR-1202 and miR-195 in the cervical cancer patients are different in different stages. Guiding clinical treatment and prognosis according to the results of combined detection is beneficial for the development of treatment for cervical cancer patients and for prognostic judgement, worthy of popularization and application.

Long noncoding RNA CYTOR sponges miR-195 to modulate proliferation, migration, invasion and radiosensitivity in nonsmall cell lung cancer cells

Nonsmall cell lung cancer (NSCLC) is one of the most frequent malignancies worldwide. Long noncoding RNAs (LncRNAs) play critical roles in cancer initiation and progression. Previous studies have demonstrated that overexpression of cytoskeleton regulator RNA (CYTOR) predicates poor prognosis and promotes tumor progression. However, the functional roles and underlying mechanism of CYTOR in NSCLC remain unknown. In the present study, we found that CYTOR promoted cell proliferation, migration and invasion ability, and induced radioresistance in NSCLC cells. Mechanistically, CYTOR could directly interact with miR-195 and increase its targets. Thus, CYTOR played an oncogenic role in NSCLC progression through sponging miR-195. Together, our study elucidates the role of CYTOR as a microRNA sponge in NSCLC, and CYTOR may be used as a promising therapeutic target for NSCLC treatment.

Epigenetic Regulation by lncRNAs: An Overview Focused on UCA1 in Colorectal Cancer

Colorectal cancers have become the second leading cause of cancer-related deaths. In particular, acquired chemoresistance and metastatic lesions occurring in colorectal cancer are a major challenge for chemotherapy treatment. Accumulating evidence shows that long non-coding (lncRNAs) are involved in the initiation, progression, and metastasis of cancer. We here discuss the epigenetic mechanisms through which lncRNAs regulate gene expression in cancer cells. In the second part of this review, we focus on the role of lncRNA Urothelial Cancer Associated 1 (UCA1) to integrate research in different types of cancer in order to decipher its putative function and mechanism of regulation in colorectal cancer cells. UCA1 is highly expressed in cancer cells and mediates transcriptional regulation on an epigenetic level through the interaction with chromatin modifiers, by direct regulation via chromatin looping and/or by sponging the action of a diversity of miRNAs. Furthermore, we discuss the role of UCA1 in the regulation of cell cycle progression and its relation to chemoresistance in colorectal cancer cells.