MicroRNA‑373 exerts anti‑tumor functions in human liver cancer by targeting Rab22a

TBC1D2 Promotes Ovarian Cancer Metastasis via Inducing E-Cadherin Degradation

Background

Ovarian cancer (OC) is the most lethal gynecological malignancy worldwide. Increasing evidence indicates that TBC domain family is implicated in various cellular events contributing to initiation and development of different cancers, including OC. However, the role of TBC1D2, a crucial member of TBC domain family, remains unclear in OC.

Methods

IHC and qRT-PCR were employed to determine TBC1D2 expression in OC tissues and cells. In vitro and in vivo assays involving proliferation, migration, invasion were performed to explore the role of TBC1D2 in OC development. The underlying mechanism by which TBC1D2 promotes OC metastasis were elucidated using bioinformatics analysis, western blotting and co-immunoprecipitation.

Results

Upregulation of TBC1D2 was found in OC and was associated with a poor prognosis. Meanwhile, TBC1D2 promoted OC cell proliferation, migration, and invasion in vitro and facilitated tumor growth and metastasis in vivo. Moreover, TBC1D2 contributed to OC cell invasion by E-cadherin degradation via disassembling Rac1-IQGAP1 complex. In addition, miR-373-3p was screened out and identified to inhibit OVCAR3 invasion via negative regulation of TBC1D2.

Conclusion

Our findings indicated that TBC1D2 is overexpressed in OC and contributes to tumor metastasis via E-cadherin degradation. This study suggests that TBC1D2 may be an underlying therapeutic target for OC.

The Role of miRNAs during Endoplasmic Reticulum Stress Induced Apoptosis in Digestive Cancer

Digestive cancer is one of the leading causes of cancer mortality in the world. Despite a number of studies being conducted, the exact mechanism for treating digestive cancer has not yet been fully understood. To survive, digestive cancer cells are subjected to various internal and external adverse factors, such as hypoxia, nutritional deficiencies or drug toxicity, resulting in accumulation of misfolded and unfolded protein in endoplasmic reticulum (ER) lumen further leading to ER stress and the unfolded protein response (UPR). During the last years, studies on the relationship between ER stress and microRNAs (miRNAs) has burst on the scene. miRNAs are non-coding RNAs with a length of 21~22nucleotides involved in post-transcriptional regulation of gene expression, which could be regarded as oncomiRs (tumor inducers) and tumor suppressors regulating cancer cell proliferation, invasion, and apoptosis by differently affecting the expression of genes related to cancer cell signaling. Therefore, investigating the interaction between ER stress and miRNAs is crucial for developing effective cancer treatment and prevention strategies. In this review, we mainly discuss miRNAs focusing on its regulation, role in ER stress induced apoptosis in Digestive cancer, expound the underlying mechanism, thus provides a theoretical foundation for finding new therapeutic targets of digestive cancer.

Down-regulation of circular RNA hsa_circ_0007534 suppresses cell growth by regulating miR-219a-5p/SOX5 axis in osteosarcoma

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The interaction between circ_0007534 and miR-219a-5p is confirmed for the first time.

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The interaction between miR-219a-5p and SOX5 is confirmed for the first time.

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Circ_0007534 knockdown inhibits the progression of osteosarcoma cells.

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Circ_0007534 regulates the growth of osteosarcoma cells through modulating miR-219a-5p/SOX5 axis.

Introduction

Circular RNA circ_0007534 and microRNA-219a (miR-219a-5p) were reported to be involved in osteosarcoma (OS) development. Osteosarcoma (OS) is one of the most common malignant bone tumors, which was more prone to occur in the metaphysis of long bones, including distal femur and proximal tibia. However, the detailed mechanisms were not fully clear. The purpose of this research was to reveal the functional mechanisms of circ_0007534 and miR-219a-5p in OS.

Methods

The levels of genes were determined by quantitative real-time polymerase chain reaction (qRT-PCR) or western blot assay. Cell proliferation ability was detected by cell counting kit-8 (CCK-8) and colony formation assay. Cell migration and invasion abilities were measured using the transwell assay. Furthermore, the interaction between miR-219a-5p and circ_0007534 or SRY (sex-determining region Y)-box 5 (SOX5) was predicted by starbaseV3.0, and confirmed by the dual-luciferase reporter assay and RNA immunoprecipitation (RIP) assay. Besides, tumor xenograft experiment was performed to analyze the effect of circ_0007534 depletion on tumor growth in vivo.

Results

The levels of circ_0007534 and SOX5 were increased, while the miR-219a-5p level was decreased in OS tissues and cells. Circ_0007534 knockdown repressed the proliferation, colony formation, migration, and invasion in OS cells. Circ_0007534 targeted miR-219a-5p, and miR-219a-5p interacted with SOX5. Furthermore, circ_0007534 regulated the growth of OS cells through modulating the levels of miR-219a-5p and SOX5.

Conclusion

Our finding demonstrated that circ_0007534 knockdown suppressed the growth of OS cells via regulating miR-219a-5p/SOX5 axis, providing a potential target for OS treatment and diagnosis.