LncRNA MATN1-AS1 for Prediction of Prognosis in Osteosarcoma Patients and Its Cellular Function

LncRNA AC100826.1 regulated PLCB1 to promote progression in non-small cell lung cancer

BACKGROUND

Lung cancer is the most common malignant tumor. In the present study, we identified a long non-coding RNA (lncRNA) AC100826.1 (simplify to Lnc1), which was highly expressed in non-small cell lung cancer (NSCLC) tissues compared with the paracancerous tissues. We also observed the critical role of Lnc1 in regulating the metastasis ability of NSCLC cells.

METHODS

RNA sequencing was performed to detect differential expression levels of lncRNAs in NSCLC tissues and its paracancerous tissues. Effects of Lnc1 on cell proliferation, invasion, and migration were determined by CCK-8, transwell and scratch assays. The xenograft experiment confirmed the effect of Lnc1 on NSCLC cells proliferation and migration abilities in vivo. RT-qPCR and western blots were performed to determine the expression levels of mRNAs and proteins.

RESULTS

The expression level of Lnc1 was related to multiple pathological results, knockdown of Lnc1 can inhibit the proliferation and metastasis abilities of NSCLC cells. silencing phospholipase C, β1(PLCB1) can reverse the promoting effects of overexpression Lnc1 on NSCLC cells proliferation and migration abilities. In addition, the Rap1 signaling pathway was implicated in the regulation of Lnc1 in NSCLC metastasis.

CONCLUSION

Our results suggest that Lnc1 regulated the metastatic ability of NSCLC cells through targeting the PLCB1/Rap1 signal pathway.

New emerging targets in osteosarcoma therapy: PTEN and PI3K/Akt crosstalk in carcinogenesis

Osteosarcoma (OS) is a malignant bone carcinoma that affects people in childhood and adulthood. The heterogeneous nature and chromosomal instability represent certain characteristics of OS cells. These cancer cells grow and migrate abnormally, making the prognosis undesirable for patients. Conventional and current treatments fail to completely eradicate tumor cells, so new therapeutics targeting genes may be considered. PI3K/Akt is a regulator of events such as growth, cell death, migration, and differentiation, and its expression changes during cancer progression. PTEN reduces PI3K/Akt expression, and its mutations and depletions have been reported in various tumors. Experimental evidence shows that there is upregulation of PI3K/Akt and downregulation of PTEN in OS. Increasing PTEN expression may suppress PI3K/Akt to minimize tumorigenesis. In addition, PI3K/Akt shows a positive association with growth, metastasis, EMT and metabolism of OS cells and inhibits apoptosis. Importantly, overexpression of PI3K/Akt causes drug resistance and radio-resistance and its level can be modulated by miRNAs, lncRNAs and circRNAs. Silencing PI3K/Akt by compounds and drugs can suppress OS. Here, we review in detail the function of the PTEN/PI3K/Akt in OS, revealing its biological function, function in tumor progression, resistance to therapy, and pharmacological significance.

Depletion of circ_0088046 suppressed cell growth and motility of hepatocellular carcinoma via circ_0088046-miR-1299-RTKN2 ceRNA pathway

Circular RNAs (circRNAs) have been verified to be important modulators and therapeutic targets of human hepatocellular carcinoma (HCC). This study aims to explore the role and mechanism of circ_0088046 in HCC progression. Quantitative real-time polymerase chain reaction (qRT-PCR), western blot and immunohistochemistry assays were used to detect the mRNA and protein expression of circ_0088046, miR-1299, Rhotekin 2 (RTKN2), Bax, Bcl-2, E-cadherin and Ki-67. Cell proliferation was investigated by 5-Ethynyl-2'-deoxyuridine (EdU) assay and cell colony formation assay. Cell apoptosis rate was measured by flow cytometry. Transwell migration and invasion assays were adopted to assess cell migration and invasion. The molecular target relationship between miR-1299 and circ_0088046 or RTKN2 were analysed by dual-luciferase reporter assay and RNA immunoprecipitation assay. An animal experiment was conducted to demonstrate the effect of circ_0088046 on tumour formation in vivo. High levels of circ_0088046 and RTKN2, and low levels of miR-1299 were displayed in HCC tissues and cells. Circ_0088046 absence repressed cell proliferation, migration and invasion, but boosted apoptosis of HCC cells. MiR-1299 was a target of circ_0088046 and miR-1299 inhibitor restored circ_0088046 silencing-mediated inhibitory impacts on HCC cell malignancy. MiR-1299 could directly target RTKN2, and overexpressed RTKN2 rescued the suppressive effects caused by miR-1299 mimic. In addition, circ_0088046 silencing constrained tumour formation in vivo. Circ_0088046 contributed to HCC cell malignancy via modulating the miR-1299/RTKN2 axis.

LncRNA-miRNA axis in tumor progression and therapy response: An emphasis on molecular interactions and therapeutic interventions

Epigenetic factors are critical regulators of biological and pathological mechanisms and they could interact with different molecular pathways. Targeting epigenetic factors has been an idea approach in disease therapy, especially cancer. Accumulating evidence has highlighted function of long non-coding RNAs (lncRNAs) as epigenetic factors in cancer initiation and development and has focused on their association with downstream targets. microRNAs (miRNAs) are the most well-known targets of lncRNAs and present review focuses on lncRNA-miRNA axis in malignancy and therapy resistance of tumors. LncRNA-miRNA regulates cell death mechanisms such as apoptosis and autophagy in cancers. This axis affects tumor metastasis via regulating EMT and MMPs. Besides, lncRNA-miRNA axis determines sensitivity of tumor cells to chemotherapy, radiotherapy and immunotherapy. Based on the studies, lncRNAs can be affected by drugs and genetic tools in cancer therapy and this may affect expression level of miRNAs as their downstream targets, leading to cancer suppression/progression. LncRNAs have both tumor-promoting and tumor-suppressor functions in cancer and this unique function of lncRNAs has complicated their implication in tumor therapy. LncRNA-miRNA axis can also affect other signaling networks in cancer such as PI3K/Akt, STAT3, Wnt/β-catenin and EZH2 among others. Notably, lncRNA/miRNA axis can be considered as a signature for diagnosis and prognosis in cancers.

Gliomas with Downregulation of lncRNA SLC25A21-AS1 Carry a Dismal Prognosis and an Accelerated Progression in Cell Proliferation, Migration and Invasion

Glioma is one type of primary intracranial carcinoma with a relatively poor prognosis. We investigated the level of SLC25A21-AS1 in gliomas and the association with survival and progression in patients with glioma. Specimens of gliomas from patients were assessed by quantitative real-time polymerase chain reaction analysis of the SLC25A21-AS1 level (117 specimens). For prognostic value assessment, χ² test, Kaplan-Meier method with the log-rank test, and Multivariate survival analysis were performed. The direct targets for SLC25A21-AS1 were explored. The biological roles of SLC25A21-AS1 were investigated by manipulating the expression level of SLC25A21-AS1 in glioma cells. SLC25A21-AS1 was significantly downregulated in glioma specimens and cell lines compared to non-cancerous ones. Significant associations were found between SLC25A21-AS1 downregulation and WHO stage, IDH status, poor disease-free survival/overall survival. miR-221-3p/miR-222-3p were the target miRNAs for SLC25A21-AS1. Overexpression of SLC25A21-AS1 inhibited glioma cell growth, invasion, and migration while miR-221-3p/miR-222-3p-overexpressed groups could offset this effect. Downregulation of SLC25A21-AS1 in gliomas carries a universally poor prognosis. Overexpression of SLC25A21-AS1 inhibited glioma progression via miR-221-3p/miR-222-3p.