LINC00858 knockdown inhibits gastric cancer cell growth and induces apoptosis through reducing WNK2 promoter methylation

LINC00858 facilitates formation of hepatic metastases from colorectal cancer via regulating the miR-132-3p/IGF2BP1 axis

Hepatic metastasis is a major cause of colorectal cancer (CRC)-related deaths. Presently, the role of long non-coding RNAs (lncRNAs) in hepatic metastases from CRC is elusive. We dissected possible interplay between LINC00858/miR-132-3p/IGF2BP1 via bioinformatics approaches. Subsequently we analyzed mRNA expression of LINC00858, miR-132-3p and IGF2BP1 through qRT-PCR. Western blot was used to detect protein expression of IGF2BP1. RNA immunoprecipitation chip and dual-luciferase assay validated interaction between LINC00858 and miR-132-3p, as well as miR-132-3p and IGF2BP1. Cell viability, invasion, and migration were examined via CCK-8, colony formation, transwell and wound healing assays. Effect of LINC00858 on CRC hepatic metastases was validated via in vivo assay. Upregulated LINC00858 and IGF2BP1, and downregulated miR-132-3p were predicted in tumor tissues of patients with hepatic metastases from CRC. There were targeting relationships between LINC00858 and miR-132-3p, as well as miR-132-3p and IGF2BP1. Besides, LINC00858 facilitated progression of CRC cells. Rescue assay suggested that silencing LINC00858 suppressed CRC cell progression, while further silencing miR-132-3p or overexpressing IGF2BP1 reversed such effects. LINC00858 could facilitate CRC tumor growth and hepatic metastases. LINC00858 induced CRC hepatic metastases via regulating miR-132-3p/ IGF2BP1, and this study may deliver a new diagnostic marker for the disease.

Long intergenic non-protein coding RNA 00858 participates in the occurrence and development of esophageal squamous cell carcinoma through the activation of the FTO-m6A-MYC axis by recruiting ZNF184

OBJECTIVES

We aimed at probing impact of LINC00858 on esophageal squamous cell carcinoma (ESCC) progression via ZNF184-FTO-m⁶A-MYC axis.

METHODS

Expression of related genes (LINC00858, ZNF184, FTO, and MYC) was detected in ESCC tissues or cells and their relationships were assessed. After expression alterations in ESCC cells, cell proliferation, invasion, migration, and apoptosis were detected. Tumor formation in nude mice was conducted.

RESULTS

LINC00858, ZNF184, FTO, and MYC were overexpressed in ESCC tissues and cells. LINC00858 enhanced ZNF184 expression to upregulate FTO, which augmented MYC expression. LINC00858 knockdown diminished ESCC cell proliferative, migratory, and invasive properties while elevating apoptosis, which was negated by FTO overexpression. FTO knockdown exerted similar functions of LINC00858 knockdown on ESCC cell movements, which was annulled by MYC upregulation. Silencing LINC00858 repressed tumor growth and related gene expression in nude mice.

CONCLUSIONS

LINC00858 modulated MYC m⁶A modification via FTO by recruiting ZNF184, thus facilitating ESCC progression.

LINC00858 stabilizes RAN expression and promotes metastasis of gastric cancer

Metastasis constitutes one of the major causes of tumor-related death in gastric cancer (GC), and understanding key events in the initiation of this phenotypic switch may provide therapeutic opportunities. Long noncoding RNAs (lncRNAs) are emerging as molecules that play vital roles in tumorigenesis and metastasis. In this study, we aimed to identify metastasis-related lncRNAs in the context of GC. The lncRNAs overexpressed in tumor tissues and positively associated with overall survival were screened out using the TCGA database. qPCR assays in clinical samples showed that LINC00858 was significantly upregulated in GC tissues compared with normal counterparts. Functional analysis suggested that LINC00858 depletion attenuated the migration, and invasion of cancer cells in vitro and suppressed the metastasis of xenografted tumors in vivo. Mechanistically, LINC00858 could interact with the metastasis-associated RAN and stabilize its protein expression by decreasing posttranslational ubiquitination. The transcription factor YY1 could bind to the promoter of LINC00858 to upregulate its expression in GC cells. Moreover, overexpression of YY1 and RAN was positively associated with upregulation of LINC00858 in GC tissues. Our results suggest that LINC00858 might play a role in GC metastasis, and be a diagnostic biomarker and potential therapeutic target.

An update regarding the role of WNK kinases in cancer

Mammalian WNK kinases (WNKs) are serine/threonine kinases that contain four members, WNK1-4. They function to maintain ion homeostasis and regulate blood pressure in mammals. Recent studies have revealed that the dysregulation of WNKs contributes to tumor growth, metastasis, and angiogenesis through complex mechanisms, especially through phosphorylating kinase substrates SPS1-related proline/alanine-rich kinase (SPAK) and oxidative stress-responsive kinase 1 (OSR1). Here, we review and discuss the relationships between WNKs and several key factors/biological processes in cancer, including ion channels, cation chloride cotransporters, sodium bicarbonate cotransporters, signaling pathways, angiogenesis, autophagy, and non-coding RNAs. In addition, the potential drugs for targeting WNK-SPAK/OSR1 signaling have also been discussed. This review summarizes and discusses knowledge of the roles of WNKs in cancer, which provides a comprehensive reference for future studies.

The tumorigenic function of LINC00858 in cancer

Long non-coding RNA (lncRNA) plays an important regulatory role in the occurrence and development of human cancer. LINC00858 is a newly discovered lncRNA with a length of 2685 nucleotides. Existing studies have shown that LINC00858 has abnormally high expression levels in malignant tumors such as colorectal cancer, gastric cancer, hepatocellular carcinoma, lung cancer, non-small cell lung cancer, ovarian cancer, osteosarcoma, retinoblastoma, Wilms tumor, bladder cancer, and cervical cancer. By regulating a variety of microRNAs, LINC00858 can affect tumor cell proliferation, invasion, metastasis, and apoptosis. Related research also found that LINC00858 is related to nuclear transcription factor/protein kinase and gene methylation. The aberrant expression of LINC00858 is related to the prognosis and clinicopathological characteristics of a variety of tumors. Overexpressed LINC00858 is closely related to the clinical stage, lymph node metastasis, and distant metastasis of cancer, including colorectal cancer, gastric cancer, non-small cell lung cancer, ovarian cancer, and Wilms tumor. Also, it is summarized that LINC00858 can regulate MAPK and TGF-β signaling pathways. This review shows that LINC00858 as an important oncogene can promote tumorigenesis and cancer development.

Circ_0001666 affects miR-620/WNK2 axis to inhibit breast cancer progression

BACKGROUND

Circular RNAs (circRNAs) play important roles in the progression of various cancers, including breast cancer (BC). However, the role of circ_0001666 in BC remains unclear.

OBJECTIVE

To explore the role of circ_0001666 in the progression of BC and reveal its potential molecular mechanism.

METHODS

Real-time polymerase chain reaction was conducted to determine the expression of circ_0001666, miR-620 and with-no-lysine kinase 2 (WNK2). Cell counting kit 8 assay, flow cytometry and transwell assay were used to measure cell proliferation, apoptosis, migration and invasion. Western blot was utilized to examine the level of protein. Dual-luciferase reporter assay and RNA immunoprecipitation assay were used to verify the interaction between miR-620 and circ_0001666 or WNK2. Mice xenotransplantation models were built to explore the effect of circ_0001666 on BC tumor growth in vivo.

RESULTS

Circ_0001666 was downregulated in BC tumor tissues and cells. Overexpressed circ_0001666 inhibited the proliferation, migration, invasion, while promoted apoptosis and tumor growth of BC in vitro or in vivo. Furthermore, circ_0001666 could serve as a sponge of miR-620. MiR-620 inhibitor hindered BC cell progression, which was similar to the effect of circ_0001666 overexpression. WNK2 was a target of miR-620, and circ_0001666 could sponge miR-620 to positive regulate WNK2. The knockdown of WNK2 reversed the effect of circ_0001666 overexpression on BC progression.

CONCLUSION

Circ_0001666 hindered the progression of BC via miR-620/WNK2 axis.

Long non-coding RNA GATA6-AS1 upregulates GATA6 to regulate the biological behaviors of lung adenocarcinoma cells

Background

Lung adenocarcinoma (LUAD) is known to be one of the leading causes of cancer-related deaths globally. In recent decades, long non-coding RNAs (lncRNAs) have been indicated to exert pivotal regulating functions in multiple biological behaviors in the initiation and development of LUAD. However, the functional mechanism of lncRNA GATA binding protein 6 antisense RNA 1 (GATA6-AS1) in LUAD has not been explored.

Methods

In the current study, GATA6-AS1 expression in LUAD tissues was revealed. Meanwhile, GATA6-AS1 expression in LUAD cells was investigated via RT-qPCR analysis. After A549 and H1975 cells were transfected with GATA6-AS1 overexpression plasmids, EdU and colony formation assays, TUNEL assays and flow cytometry analyses, as well as wound healing and Transwell assays were conducted to detect cell proliferation, apoptosis, migration and invasion. Afterwards, bioinformatic tools, western blot analyses, dual-luciferase reporter assays, and RNA immunoprecipitation (RIP) assays were performed to investigate the correlation of microRNA-4530 (miR-4530), GATA6-AS1 and GATA6.

Results

We found that GATA6-AS1 expression was low-expressed in LUAD tissues and cells. Furthermore, the upregulation of GATA6-AS1 suppressed the proliferative, migration and invasion abilities, as well as promoted apoptotic rate of A549 and H1975 cells. Moreover, the mechanistic investigations revealed that GATA6-AS1 upregulated the expression of its cognate sense gene GATA6 by binding with miR-4530, thereby modulating the malignant progression of LUAD cells.

Conclusions

GATA6-AS1 repressed LUAD cell proliferation, migration and invasion, and promoted cell apoptosis via regulation of the miR-4530/GATA6 axis, indicating GATA6-AS1 as a new prognostic biomarker for LUAD.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12890-021-01521-7.