Deletion of HNF1A-AS1 Suppresses the Malignant Phenotypes of Breast Cancer Cells In Vitro and In Vivo Through Targeting miRNA-20a-5p/TRIM32 Axis

Intricate confrontation: Research progress and application potential of TRIM family proteins in tumor immune escape

BACKGROUND

Tripartite motif (TRIM) family proteins have more than 80 members and are widely found in various eukaryotic cells. Most TRIM family proteins participate in the ubiquitin-proteasome degradation system as E3-ubiquitin ligases; therefore, they play pivotal regulatory roles in the occurrence and development of tumors, including tumor immune escape. Due to the diversity of functional domains of TRIM family proteins, they can extensively participate in multiple signaling pathways of tumor immune escape through different substrates. In current research and clinical contexts, immune escape has become an urgent problem. The extensive participation of TRIM family proteins in curing tumors or preventing postoperative recurrence and metastasis makes them promising targets.

AIM OF REVIEW

The aim of the review is to make up for the gap in the current research on TRIM family proteins and tumor immune escape and propose future development directions according to the current progress and problems.

KEY SCIENTIFIC CONCEPTS OF REVIEW

This up-to-date review summarizes the characteristics and biological functions of TRIM family proteins, discusses the mechanisms of TRIM family proteins involved in tumor immune escape, and highlights the specific mechanism from the level of structure-function-molecule-pathway-phenotype, including mechanisms at the level of protein domains and functions, at the level of molecules and signaling pathways, and at the level of cells and microenvironments. We also discuss the application potential of TRIM family proteins in tumor immunotherapy, such as possible treatment strategies for combination targeting TRIM family protein drugs and checkpoint inhibitors for improving cancer treatment.

Osthole exhibits an antitumor effect in retinoblastoma through inhibiting the PI3K/AKT/mTOR pathway via regulating the hsa_circ_0007534/miR-214-3p axis

CONTEXT

Osthole shows antitumor effects in various tumours. Studies describing the effect of osthole on retinoblastoma (RB) are rare.

OBJECTIVE

This study investigates the antitumor activity of osthole on RB.

MATERIALS AND METHODS

RB cells were treated with different concentrations of osthole and then subjected to cell viability, colony formation, apoptosis, and western blot assays. The expression of hsa_circ_0007534 in RB tissues was determined by qRT-PCR. Hsa_circ_0007534 overexpression plasmid (oe-circ_0007534), miR-214-3p mimics and negative controls were transfected into RB cells to investigate cell viability. Athymic nude mice were injected with Y-79 cells to establish subcutaneous RB models. These mice were treated with osthole (0.5 mmol/kg) or corn oil for 36 days. Tumour tissues were collected for further analysis.

RESULTS

Osthole inhibited cell viability of RB cells with an IC₅₀ of 200 μM for 24 h treatment and 120 μM for 48 h treatment, respectively. Hsa_circ_0007534 was increased significantly in RB tissues as compared to the matched nontumor tissues (p < 0.001). Oe-circ_0007534 counteracted the inhibitory effect of osthole on cell viability and colony numbers of Y-79 cells (p < 0.01). In vivo experiments indicated osthole significantly decreased the expression of hsa_circ_0007534 (p < 0.01) and increased the level of miR-214-3p in vivo. Furthermore, as compared to the control, osthole decreased the ratios of p-PI3K/PI3K, p-AKT/AKT and p-mTOR/mTOR (p < 0.01). However, hsa_circ_0007534 overexpression reversed the effect of osthole on the PI3K/AKT/mTOR pathway.

DISCUSSION AND CONCLUSIONS

Osthole exhibited an antitumour effect in RB, providing a scientific basis for further research and clinical applications of osthole in RB treatment.

HNF1A-AS1：A tumor-associated long non-coding RNA

BACKGROUND

Hepatocyte nuclear factor 1 homeobox A antisense RNA 1 (HNF1A-AS1) is a Long non-coding RNA（LncRNA）that participates in the occurrence development of lots of tumors and is supposed to be a new biomarker. The text aims to illustrate the biological effect, specific mechanism and clinical significance of HNF1A-AS1 in various tumors.

METHODS

Via consulting the literature, analyze and summarize the relationship between HNF1A-AS1 and all kinds of tumors and the specific mechanism.

RESULTS

This is a review paper about the tumor-associated long non-coding RNA HNF1A-AS1. Many Researches show that LncRNA HNF1A-AS1 is related to the development of tumorous tumors. Its expression is up-regulated in numerous tumors, such as oral squamous cell carcinoma, hepatocellular carcinoma, breast cancer, osteosarcoma， lung cancer, cervical cancer, bladder cancer, colon cancer, colorectal cancer, oesophageal adenocarcinoma and laryngeal squamous cell carcinoma. However, HNF1A-AS1 is down-regulated in gastroenteropancreatic, neuroendocrine neoplasms, oral squamous cell carcinoma. Furthermore, HNF1A-AS1 can affect tumor proliferation, invasion, migration and apoptosis by targeting some microRNAs-miR-661 and miR-124. Or HNF1A-AS1 can also influence the development of tumors by regulating EMT.

CONCLUSION

These studies show that LncRNA-HNF1A-AS1 is closely related to the occurrence development of numerous cancers. Through various molecular mechanisms to regulate tumor growth, HNF1A-AS1 can possibly become the new biological biomarker and therapeutic target for many kinds of tumors.

Circulating miRNAs in Breast Cancer Diagnosis and Prognosis

Great improvement has been made in the diagnosis and therapy of breast cancer patients. However, the identification of biomarkers for early diagnosis, prognosis, therapy assessment and monitoring, including drug resistance and the early detection of micro-metastases, is still lacking. Recently, circulating microRNAs (miRNAs), circulating freely in the blood stream or entrapped in extracellular vesicles (EVs), have been shown to have a potential diagnostic, prognostic or predictive power. In this review, recent findings are summarized, both at a preclinical and clinical level, related to miRNA applicability in the context of breast cancer. Different aspects, including clinical and technical challenges, are discussed, describing the potentialities of miRNA use in breast cancer. Even though more methodological standardized studies conducted in larger and selected patient cohorts are needed to support the effective clinical utility of miRNA as biomarkers, they could represent novel and accessible tools to be transferred into clinical practice.

The Role of SUMO E3 Ligases in Signaling Pathway of Cancer Cells

Small ubiquitin-like modifier (SUMO)ylation is a reversible post-translational modification that plays a crucial role in numerous aspects of cell physiology, including cell cycle regulation, DNA damage repair, and protein trafficking and turnover, which are of importance for cell homeostasis. Mechanistically, SUMOylation is a sequential multi-enzymatic process where SUMO E3 ligases recruit substrates and accelerate the transfer of SUMO onto targets, modulating their interactions, localization, activity, or stability. Accumulating evidence highlights the critical role of dysregulated SUMO E3 ligases in processes associated with the occurrence and development of cancers. In the present review, we summarize the SUMO E3 ligases, in particular, the novel ones recently identified, and discuss their regulatory roles in cancer pathogenesis.

Dexmedetomidine alleviates the hypoxic-ischemic brain damage via miR-20a-5p/methionine adenosyltransferase 2B axis in rat pups

OBJECTIVE

The neuroprotective effect of dexmedetomidine (DEX) has been demonstrated in hypoxic-ischemic brain damage (HIBD) animal models, the mechanism of which will be the foothold in this work.

METHODS

After establishment of HIBD rat model, the rats were treated with DEX, miR-20a-5p agomir and adenoviral methionine adenosyltransferase 2B (MAT2B) overexpression vector, and then their brain tissues were harvested. The infarction volume and pathological changes of these brain tissues were measured using the triphenyl tetrazolium chloride (TTC), Nissl and hematoxylin-eosin (HE) stainings. The levels of miR-20a-5p, Bcl-2, Bax and MAT2B in these brain tissues were detected by Real-Time PCR (RT-PCR) and western blot. The binding sites of MAT2B and miR-20a-5p were predicted using the TargetScan and verified using the dual-luciferase reporter assay. The memory deficits and spatial learning of rat pups were assessed by Morris water maze test.

RESULTS

MiR-20a-5p expression was upregulated, while MAT2B expression was downregulated in rats with HIBD. MAT2B was targeted by miR-20a-5p. DEX treatment improved the neurons and hippocampal tissue damage and decreased miR-20a-5p level in brain tissues of rats with HIBD. MiR-20a-5p overexpression overturned the protective effect of DEX on brain tissues and learning and memory abilities in rats with HIBD. Moreover, DEX promoted Bcl-2 level while inhibiting Bax level in HIBD rats' brain tissues. Besides, overexpressed MAT2B reversed the effect of overexpressed miR-20a-5p on the levels of MAT2B, Bcl-2 and Bax, brain tissue damage, as well as the learning and memory abilities in rats with HIBD.

CONCLUSION

DEX alleviated HIBD via the miR-20a-5p/MAT2B axis in rats.

lncRNAfunc: a knowledgebase of lncRNA function in human cancer

The long non-coding RNAs associating with other molecules can coordinate several physiological processes and their dysfunction can impact diverse human diseases. To date, systematic and intensive annotations on diverse interaction regulations of lncRNAs in human cancer were not available. Here, we built lncRNAfunc, a knowledgebase of lncRNA function in human cancer at https://ccsm.uth.edu/lncRNAfunc, aiming to provide a resource and reference for providing therapeutically targetable lncRNAs and intensive interaction regulations. To do this, we collected 15 900 lncRNAs across 33 cancer types from TCGA. For individual lncRNAs, we performed multiple interaction analyses of different biomolecules including DNA, RNA, and protein levels. Our intensive studies of lncRNAs provide diverse potential mechanisms of lncRNAs that regulate gene expression through binding enhancers and 3'-UTRs of genes, competing for miRNA binding sites with mRNAs, recruiting the transcription factors to gene promoters. Furthermore, we investigated lncRNAs that potentially affect the alternative splicing events through interacting with RNA binding Proteins. We also performed multiple functional annotations including cancer stage-associated lncRNAs, RNA A-to-I editing event-associated lncRNAs, and lncRNA expression quantitative trait loci. lncRNAfunc is a unique resource for cancer research communities to help better understand potential lncRNA regulations and therapeutic lncRNA targets.

Inhibition of TRIM32 by ibr-7 treatment sensitizes pancreatic cancer cells to gemcitabine via mTOR/p70S6K pathway

Pancreatic cancer is one of the most notorious diseases for being asymptomatic at early stage and high mortality rate thereafter. However, either chemotherapy or targeted therapy has rarely achieved success in recent clinical trials for pancreatic cancer. Novel therapeutic regimens or agents are urgently in need. Ibr‐7 is a novel derivative of ibrutinib, displaying superior antitumour activity in pancreatic cancer cells than ibrutinib. In vitro studies showed that ibr‐7 greatly inhibited the proliferation of BxPC‐3, SW1990, CFPAC‐1 and AsPC‐1 cells via the induction of mitochondrial‐mediated apoptosis and substantial suppression of mTOR/p70S6K pathway. Moreover, ibr‐7 was able to sensitize pancreatic cancer cells to gemcitabine through the efficient repression of TRIM32, which was positively correlated with the proliferation and invasiveness of pancreatic cancer cells. Additionally, knockdown of TRIM32 diminished mTOR/p70S6K activity in pancreatic cancer cells, indicating a positive feedback loop between TRIM32 and mTOR/p70S6K pathway. To conclude, this work preliminarily explored the role of TRIM32 in the malignant properties of pancreatic cancer cells and evaluated the possibility of targeting TRIM32 to enhance effectiveness of gemcitabine, thereby providing a novel therapeutic target for pancreatic cancer.

MiR-20a-5p functions as a potent tumor suppressor by targeting PPP6C in acute myeloid leukemia

Acute myeloid leukemia (AML) is as a highly aggressive and heterogeneous hematological malignancy. MiR-20a-5p has been reported to function as an oncogene or tumor suppressor in several tumors, but the clinical significance and regulatory mechanisms of miR-20a-5p in AML cells have not been fully understood. In this study, we found miR-20a-5p was significantly decreased in bone marrow from AML patients, compared with that in healthy controls. Moreover, decreased miR-20a-5p expression was correlated with risk status and poor survival prognosis in AML patients. Overexpression of miR-20a-5p suppressed cell proliferation, induced cell cycle G0/G1 phase arrest and apoptosis in two AML cell lines (THP-1 and U937) using CCK-8 assay and flow cytometry analysis. Moreover, miR-20a-5p overexpression attenuated tumor growth in vivo by performing tumor xenograft experiments. Luciferase reporter assay and western blot demonstrated that protein phosphatase 6 catalytic subunit (PPP6C) as a target gene of miR-20a-5p was negatively regulated by miR-20a-5p in AML cells. Furthermore, PPP6C knockdown imitated, while overexpression reversed the effects of miR-20a-5p overexpression on AML cell proliferation, cell cycle G1/S transition and apoptosis. Taken together, our findings demonstrate that miR-20a-5p/PPP6C represent a new therapeutic target for AML and a potential diagnostic marker for AML therapy.

Hepatocyte nuclear factor 1A-antisense: Review of its role in the carcinogenesis

Hepatocyte nuclear factor 1A-antisense (HNF1A-AS) is an RNA gene classified as a long non-coding RNA (lncRNA). This gene is located on 12q24.31 and produces at least seven transcripts. This lncRNA contributes in the pathogenesis of cancer via HNF1A-dependent and -independent routes. Moreover, the role of this lncRNA in this process is context-dependent. The bulk of evidence from cell line, in vivo and clinical studies propose HNF1A-AS as an oncogenic lncRNA. However, in hepatic cancer, gastric cancer and laryngeal cancer, opposite results have been reported. In the current review, we explain the impact of HNF1A-AS in the pathoetiology of cancers. In order to appraise the importance of available evidence on this topic, we have classified evidence to preclinical models (cell liens and animal models) and investigations in tissues obtained from human subjects.

GCRFLDA: scoring lncRNA-disease associations using graph convolution matrix completion with conditional random field

Long noncoding RNAs (lncRNAs) play important roles in various biological regulatory processes, and are closely related to the occurrence and development of diseases. Identifying lncRNA-disease associations is valuable for revealing the molecular mechanism of diseases and exploring treatment strategies. Thus, it is necessary to computationally predict lncRNA-disease associations as a complementary method for biological experiments. In this study, we proposed a novel prediction method GCRFLDA based on the graph convolutional matrix completion. GCRFLDA first constructed a graph using the available lncRNA-disease association information. Then, it constructed an encoder consisting of conditional random field and attention mechanism to learn efficient embeddings of nodes, and a decoder layer to score lncRNA-disease associations. In GCRFLDA, the Gaussian interaction profile kernels similarity and cosine similarity were fused as side information of lncRNA and disease nodes. Experimental results on four benchmark datasets show that GCRFLDA is superior to other existing methods. Moreover, we conducted case studies on four diseases and observed that 70 of 80 predicted associated lncRNAs were confirmed by the literature.

GATA1-Activated HNF1A-AS1 Facilitates the Progression of Triple-Negative Breast Cancer via Sponging miR-32-5p to Upregulate RNF38

Background

Triple-negative breast cancer (TNBC) is a highly invasive subtype of breast cancer with a high mortality rate. Recently, long non-coding RNAs (lncRNAs) are confirmed to modulate the progression of assorted cancers, including TNBC. However, the functions of lncRNA HNF1 homeobox A antisense RNA 1 (HNF1A-AS1) in TNBC are still unclear.

Aim

We aimed to investigate the function and mechanism of HNF1A-AS1 in TNBC.

Methods

The expression of genes in TNBC cells was tested by quantitative real-time polymerase chain reaction (qRT-PCR) and Western blot. In vitro loss-of-function assays and in vivo xenograft experiments were conducted for evaluating the impact of HNF1A-AS1 on TNBC progression. RNA pull-down, luciferase reporter and RNA immunoprecipitation (RIP) assays were utilized for assessing the correlations between molecules.

Results

We discovered that HNF1A-AS1 was highly expressed in TNBC tissues and cells. Knockdown of HNF1A-AS1 restrained cell proliferation but accelerated cell apoptosis. Besides, GATA-binding protein 1 (GATA1) activated HNF1A-AS1 transcription in TNBC. MicroRNA-32-5p (miR-32-5p) was slowly expressed in TNBC cells and sponged by HNF1A-AS1, and its overexpression hinders TNBC cell growth. Ring finger protein 38 (RNF38) was verified as the target of miR-32-5p, and HNF1A-AS1 was a competing endogenous RNA (ceRNA) of RNF38 through sponging miR-32-5p. Rescue experiments indicated that upregulation of RNF38 reversed the inhibited impacts of silencing HNF1A-AS1 on TNBC cell growth.

Conclusion

GATA1-activated HNF1A-AS1 facilitated TNBC progression via miR-32-5p/RNF38 axis. The findings may provide new roads for developing targeted therapies of TNBC.

lncRNA FLVCR1‑AS1 drives colorectal cancer progression via modulation of the miR‑381/RAP2A axis

Colorectal cancer (CRC) is one of the most prevalent types of cancer globally. Long non-coding RNAs (lncRNAs) have been suggested to serve as vital regulators in CRC. lncRNA feline leukemia virus subgroup C receptor 1 antisense RNA 1 (FLVCR1-AS1) is closely associated with the tumorigenesis of various types of cancer. The aim of the present study was to investigate the molecular mechanisms of lncRNA FLVCR1-AS1 in CRC progression. The expression levels of FLVCR1-AS1, microRNA (miR)-381 and Ras-related protein 2a (RAP2A) were measured by reverse transcription-quantitative polymerase chain reaction (RT-qPCR). A Kaplan-Meier analysis was performed to determine the overall survival rate of patients with CRC. Furthermore, cell viability, migration and invasion were assessed using Cell Counting Kit-8 (CCK-8) and Transwell assays. The interaction between genes was confirmed using dual-luciferase reporter and pull-down assays. The results demonstrated that FLVCR1-AS1 was upregulated in CRC tissues and cells, and increased FLVCR1-AS1 expression levels in patients with CRC were associated with poor prognosis. FLVCR1-AS1 knockdown significantly attenuated the viability, migration and invasion ability of CRC cells. In addition, the results confirmed that FLVCR1-AS1 directly binds with miR-381-3p, and that RAP2A is a direct target of miR-381-3p. The overexpression of FLVCR1-AS1 increased RAP2A expression levels. Functional assays revealed that miR-381 inhibitor or RAP2A overexpression attenuated the suppressive effects of FLVCR1-AS1 silencing on CRC cell viability, migration and invasion. Overall, the findings of the current study suggest that FLVCR1-AS1 promotes CRC progression via the miR-381/RAP2A pathway. These findings may provide a novel approach for CRC treatment.