Upregulation of the long non-coding RNA FAM83H-AS1 in gastric cancer and its clinical significance

WTAP-Involved the m6A Modification of lncRNA FAM83H-AS1 Accelerates the Development of Gastric Cancer

The long noncoding RNA FAM83H-antisense RNA 1 (FAM83H-AS1) is involved in gastric cancer (GC) development. This study determined whether FAM83H-AS1 was regulated by N6-methyladenosine (m6A) modifications in GC. Real-time quantitative polymerase chain reaction was performed to determine the expression levels of FAM83H-AS1 and Wilms' tumor 1 associated protein (WTAP). The protein content of WTAP was evaluated using western blotting. To assess the m6A alterations in FAM83H-AS1, methylated RNA immunoprecipitation was performed to identify interactions between WTAP and FAM83H-AS1. Functionally, the proliferation, migration, and invasion of GC cells were measured using a Cell Counting Kit-8 and transwell assays, respectively. High expression levels of FAM83H-AS1 and WTAP were detected in GC samples and there was a positive correlation between them. In addition, WTAP mediates FAM83H-AS1 expression in an m6A-dependent manner. Further investigations indicated that WTAP silencing reversed the cancer-promoting role of FAM83H-AS1 overexpression in GC cell migration, proliferation, and invasion. Our results suggest that WTAP-mediated FAM83H-AS1 promotes GC development via m6A modification. Our findings provide new biomarkers for GC diagnosis and targeted therapy.

Antisense long non-coding RNAs in gastric cancer

Gastric cancer is a global health problem with high mortality. The incidence of gastric cancer has significant regional differences. Helicobacter pylori (H. pylori) infection and its interaction with epigenetics are closely related to the occurrence of gastric cancer. It is of great significance to explore the early diagnosis and effective therapeutic targets of gastric cancer. Emerging evidence indicates that antisense long non-coding RNAs (lncRNAs) are closely associated with various biological and functional aspects of gastric cancer. However, diverse antisense lncRNAs in gastric cancer have not been compiled and discussed. In this review, we summarize the predisposing factors and compile the interaction between H. pylori and epigenetics in gastric cancer. Moreover, we focus on the underlying molecular mechanism and regulatory role of each antisense lncRNA in gastric cancer. In addition, we provide a new insight into the potential diagnosis and treatment of antisense lncRNAs in gastric cancer.

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.

A Novel Androgen-Induced lncRNA FAM83H-AS1 Promotes Prostate Cancer Progression via the miR-15a/CCNE2 Axis

Prostate cancer (PCa) is one of the most common types of tumors among males worldwide. However, the roles of long noncoding RNAs (lncRNAs) in PCa remain unclear. This study shows that lncRNA FAM83H-AS1 is upregulated in prostate adenocarcinoma, bladder urothelial carcinoma, and kidney renal papillary cell carcinoma samples. Androgen receptor (AR) signaling plays the most important role in PCa tumorigenesis and development. In this study, the results validate that AR signaling is involved in upregulating FAM83H-AS1 expression in PCa cells. Loss-of-function assays demonstrate that FAM83H-AS1 acts as an oncogene in PCa by modulating cell proliferation, cell cycle, and migration. Bioinformatics analysis demonstrates that FAM83H-AS1 is remarkably related to the regulation of the cell cycle and DNA replication through affecting multiple regulators related to these pathways, such as CCNE2. Mechanically, we found that FAM83H-AS1 plays its roles through sponging miR-15a to promote CCNE2 expression. These findings indicate that FAM83H-AS1 is a novel diagnostic and therapeutic marker for PCa.

FAM83H-AS1 is a noncoding oncogenic driver and therapeutic target of lung adenocarcinoma

BACKGROUND

Little is known about noncoding oncogenes of lung adenocarcinoma (LUAD), and these potential drivers might provide novel therapeutic targets.

METHODS

Since abnormally overexpression of oncogenic drivers is induced by genomic variation, we here utilized genomic, transcriptomic, and clinical prognosis data of The Cancer Genome Atlas (TCGA) LUAD datasets to discover novel drivers from long noncoding RNAs. We further used zebrafish models to validate the biological function of candidates in vivo. The full length of FAM83H-AS1 was obtained by rapid amplification of the cDNA ends assay. RNA pull-down, RNA immunoprecipitation, quantitative mass spectrometry, and RNA sequencing assays were conducted to explore the potential mechanisms. Additionally, we used CRISPR interference (CRISPRi) method and patient-derived tumor xenograft (PDTX) model to evaluate the therapeutic potential of targeting FAM83H-AS1.

RESULTS

The results suggest that FAM83H-AS1 is a potential oncogenic driver due to chromosome 8q24 amplification. Upregulation of FAM83H-AS1 results in poor prognosis of LUAD patients in both Jiangsu Cancer Hospital (JSCH) and TCGA cohorts. Functional assays revealed that FAM83H-AS1 promotes malignant progression and inhibits apoptosis. Mechanistically, FAM83H-AS1 binds HNRNPK to enhance the translation of antiapoptotic oncogenes RAB8B and RAB14. Experiments using CRISPRi-mediated xenografts and PDTX models indicated that targeting FAM83H-AS1 inhibited LUAD progression in vivo.

CONCLUSIONS

Our work demonstrates that FAM83H-AS1 is a noncoding oncogenic driver that inhibits LUAD apoptosis via the FAM83H-AS1-HNRNPK-RAB8B/RAB14 axis, which highlights the importance and potential roles that FAM83H-AS1 may serve as a novel therapeutic target for LUAD.

LncRNA FAM83H-AS1 maintains intervertebral disc tissue homeostasis and attenuates inflammation-related pain via promoting nucleus pulposus cell growth through miR-22-3p inhibition

Background

Intervertebral disc degeneration (IVDD) is regarded as the leading cause of low back pain, resulting in disability and a heavy burden on public health. Several studies have unveiled that long noncoding RNAs (lncRNAs) play a key role in the pathogenesis and progression of IVDD. In this study, we aimed to investigate the biological function and latent molecular mechanism of the lncRNA FAM83H antisense RNA 1 (FAM83H-AS1) in IVDD development.

Methods

Firstly, we established an IVDD model in rats using advanced glycation end products (AGEs) intradiscal injection. Subsequently, gain-of-function assays were conducted to investigate the role of FAM83H-AS1 in the progression of IVDD. Bioinformatics analysis, RNA pull down assay and rescue experiments were employed to shed light on the molecular mechanism underlying FAM83H-AS1 involving in IVDD.

Results

Our findings verified that AGEs treatment aggravated IVDD damage, and FAM83H-AS1 was downregulated in the IVDD group. Additionally, overexpression of FAM83H-AS1 contributed to the growth of nucleus pulposus (NP) cells and ameliorated IVDD injury. It was revealed that FAM83H-AS1 possessed the speculated binding sites of miR-22-3p. More importantly, we confirmed that FAM83H-AS1 functioned as a sponge of miR-22-3p in IVDD. Lastly, we demonstrated that miR-22-3p mediated the impact of FAM83H-AS1 on cell proliferation, ECM degradation, and inflammation.

Conclusions

Our study indicated that FAM83H-AS1 relieved IVDD deterioration through sponging miR-22-3p, and provides novel insights into the mechanisms underlying FAM83H-AS1 in IVDD progression.

Long non-coding RNA FAM83H-AS1 as an emerging marker for diagnosis, prognosis and therapeutic targeting of cancer

Incidence and mortality rates of cancer continue to increase greatly despite the improved diagnostic and therapeutic methods. Based on GLOBOCAN estimates, the numbers of new cancer cases reported in 2018 were ~18.1 million, while the numbers of cancer mortalities were ~9.6 million. It remains difficult to diagnose most cancer patients at early stages. Although cancer therapy market is rapidly evolving, the effectiveness of therapy is still inadequate. Therefore, exploring new biomarkers for diagnosis, prognosis and treatment is essential for cancer management. Long non-coding RNAs (lncRNAs) are unique regulatory molecules that control several cellular processes and are implicated in diverse human diseases including cancer. LncRNAs could serve as potential biomarkers for cancer patients to aid diagnosis and determine prognosis. In addition, numerous lncRNAs have proved their ability to predict response to cancer treatment. FAM83H antisense RNA 1 (FAM83H-AS1) is among those highly dysregulated lncRNAs in cancer. FAM83H-AS1 was demonstrated to participate in the progression of different malignancies and also shown to play a vital role in diagnosis, prognosis and treatment. Here, we analyse recent studies concerning the oncogenic role and molecular mechanisms of lncRNA FAM83H-AS1 in the following cancer types: bladder, breast, lung, hepatocellular, colorectal, gastric, pancreatic, ovarian, cervical cancer as well as glioma.

The clinical prognostic value of lncRNA FAM83H-AS1 in cancer patients: a meta-analysis

Background

Family with sequence similarity 83 member H antisense RNA 1 (FAM83H-AS1) is a novel long non-coding RNA. Increasing studies have reported that FAM83H-AS1 is abnormally expressed in a variety of tumors and is associated with poor outcome. However, the clinical prognostic significance of lncRNA FAM83H-AS1 in tumors is not completely known.

Methods

In this meta-analysis, literature was collected up until February 5, 2020 through multifarious retrieval strategies by searching through electronic databases of PubMed, Cochrane Library, EMBASE, Medline, Web of Science, CNKI, Weipu, and Wanfang. A total of 14 studies that met the inclusion criteria with relevant clinical data and prognostic information were included in the meta-analysis.

Results

The combined results revealed that high expression of FAM83H-AS1 was associated with poor overall survival (OS) (HR = 1.63, 95% CI 1.24–2.14, P = 0.0004) in a variety of cancers. Additionally, upregulated FAM83H-AS1 expression was significantly correlated with tumor TNM stage (III/IV vs. I/II, OR = 2.40, 95% CI 1.36–4.23, P = 0.003) and lymph node metastasis (positive vs. negative, OR = 1.70, 95% CI 1.14–2.52, P = 0.008) in patients with cancer.

Conclusions

Our results of this meta-analysis indicated that elevated FAM83H-AS1 expression could predict poor prognosis in patients with cancer and suggested that FAM83H-AS1 might serve as a novel biomarker for cancer.

Long Noncoding RNA RGMB-AS1 Acts as a microRNA-574 Sponge Thereby Enhancing the Aggressiveness of Gastric Cancer via HDAC4 Upregulation

PURPOSE

The long noncoding RNA RGMB-AS1 plays an important part in the genesis and progression of multiple human cancers. Nonetheless, little is known regarding its expression, roles, and mechanisms of action in gastric cancer (GC). This study was aimed at investigating the relationship between RGMB-AS1 and GC and illustrating the mechanisms of action of RGMB-AS1 therein.

METHODS

RGMB-AS1 expression in GC was measured via reverse-transcription quantitative PCR. A series of experiments including Cell Counting Kit-8 assay, flow-cytometric analysis of apoptosis, Transwell migration and invasion assays, and in vivo tumorigenesis experiment were conducted to test the effects of RGMB-AS1 on the malignant phenotype of GC cells. The molecular events behind the oncogenic actions of RGMB-AS1 in GC were elucidated through subcellular fractionation, RNA immunoprecipitation assay, bioinformatics analysis and luciferase reporter assay.

RESULTS

RGMB-AS1 upregulation was confirmed in GC tissues and cell lines. Higher RGMB-AS1 expression was associated with adverse clinical parameters and negatively correlated with patient overall survival. RGMB-AS1 knockdown inhibited GC cell proliferation, facilitated apoptosis, and reduced migration and invasion in vitro. Further experiments revealed that RGMB-AS1 knockdown decreased the tumor growth of GC cells in vivo. Mechanistically, RGMB-AS1 functioned as a competing endogenous RNA upregulating histone deacetylase 4 (HDAC4) by sponging microRNA-574 (miR-574). Rescue experiments indicated that miR-574 inhibition and HDAC4 reintroduction reversed the effects of the RGMB-AS1 knockdown on GC cells.

CONCLUSION

The RGMB-AS1-miR-574-HDAC4 regulatory network contributes to the malignancy of GC, thereby offering a novel target for the diagnosis, prognosis, and/or treatment of GC.

Silence of FAM83H-AS1 promotes chemosensitivity of gastric cancer through Wnt/β-catenin signaling pathway

Gastric cancer (GC) is a malignant tumor originated from the epithelium of gastric mucosa, its incidence is second only to lung cancer in China. Chemotherapy is one of the most effective methods to treat GC, but some patients are insensitive to chemotherapeutic drugs, leading to chemotherapy failure. In this study, the expression of FAM83H-AS1 was up-regulated in GC tissues and cell lines, and was related to differentiation, invasion depth and chemotherapy insensitivity of GC patients. FAM83H-AS1 was high-expressed in chemoresistant GC tissues and cell line (SGC7901/R), and silence of FAM83H-AS1 sensitized SGC7901/R cells to cisplatin (CDDP) and 5-fluorouracil (5-FU). In addition, silence of FAM83H-AS1 could inactivate Wnt/β-catenin signaling pathway in SGC7901/R cells. The activating of Wnt/β-catenin signaling pathway reversed the promoting effect of FAM83H-AS1 silence on chemotherapy sensitivity, which meant Wnt/β-catenin signaling pathway mediated the regulation of FAM83H-AS1 on chemotherapy sensitivity in SGC7901/R cells. In conclusion, FAM83H-AS1 is related with the CDDP and 5-FU insensitivity of GC patients, silence of FAM83H-AS1 promotes chemosensitivity of GC through Wnt/β-catenin signaling pathway.