Circular RNA circVAPA contributes to non-small-cell lung cancer progression via miR-342-3p-dependent regulation of ZEB2

Circ_0000758 Facilitates Bladder Cancer Cell Growth, Migration and Angiogenesis Via Severing as miR-1236-3p Sponge

Circular RNA (circRNA) has been reported to regulate the development of bladder cancer (BCa). However, the role of circ_0000758 in BCa progression is unknown. Circ_0000758 and miR-1236-3p expression, as well as ZEB2 mRNA expression were determined by qRT-PCR. BCa cell biological functions were determined by MTT assay, EdU assay, flow cytometry, wound healing assay and tube formation assay. Protein expression was detected by western blot analysis. RNA pull-down assay and dual-luciferase reporter assay were used to confirm RNA interaction. Xenograft mice models were constructed to assess the effect of circ_0000758 on BCa tumor growth. Circ_0000758 had increased expression in BCa tissues and cells. Circ_0000758 silencing could inhibit BCa cell growth, migration, angiogenesis in vitro, and tumor growth in vivo. Circ_0000758 served as a molecular sponge for miR-1236-3p, and miR-1236-3p inhibitor reversed circ_0000758 knockdown-mediated the inhibition effect on BCa cell progression. ZEB2 was targeted by miR-1236-3p, and its overexpression also revoked the suppressive effect of miR-1236-3p on BCa cell growth, migration, and angiogenesis. Besides, circ_0000758 knockdown also restrained BCa tumor growth. Circ_0000758 might promote BCa cell growth, migration, and angiogenesis by regulating the miR-1236-3p/ZEB2 axis.

Circular RNA circVAPA modulates macrophage pyroptosis in sepsis-induced acute lung injury through targeting miR-212-3p/Sirt1/Nrf2/NLRP3 axis

Sepsis-induced acute lung injury (ALI) is an inflammatory condition involving the pyroptosis of macrophages. This study investigated the role of circular RNA hsa_circ_0006990 (circVAPA) in regulating macrophage pyroptosis in ALI and the underlying mechanisms. The expression pattern of circVAPA was examined in the mouse model of ALI and in the LPS-treated RAW264.7 macrophage cell line. Lung tissue damage was evaluated by haematoxylin and eosin staining, immunohistochemistry and a myeloperoxidase activity assay. The molecular mechanisms were investigated by luciferase reporter assay, western blot, RT-qPCR and ELISA. circVAPA was down-regulated in the lung tissues of ALI mice and LPS-induced RAW264.7 cells. circVAPA over-expression alleviated lung tissue injury and dampened LPS-induced pyroptosis and Th17-associated inflammatory responses. miR-212-3p was identified as a target of circVAPA, and miR-212-3p negatively regulated the expression of Sirt1. Sirt1 knockdown largely abolished the effect of circVAPA over-expression on pyroptosis. CircVAPA/miR-212-3p/Sirt1 axis also regulates Nrf2 and NLRP3 expression upon LPS challenge. By targeting miR-212-3p, circVAPA over-expression negatively regulates the expression of Sirt1 and pyroptosis-related factors (Nrf2 and NLRP3), which alleviates the inflammatory damages in sepsis-induced ALI.

M2 macrophage-derived extracellular vesicles augment immune evasion and development of colorectal cancer via a circRNA_CCDC66/microRNA-342-3p/metadherin axis

The M2 macrophages are major components in the tumor microenvironment and are closely linked to immune suppression and tumor metastasis. This work focuses on how M2 macrophage-derived extracellular vesicles (EVs) affect colorectal cancer (CRC) progression. THP-1 monocytes were induced to differentiate to M0 or M2 macrophages, and the macrophage-derived EVs (M0-EVs and M2-EVs, respectively) were collected and identified. The M2-EVs stimulation augmented proliferation, mobility, and the in vivo tumorigenic activity of CRC cells. Circular RNA_CCDC66 (circ_CCDC66) was highly enriched in M2-EVs and could be delivered into CRC cells. The RNA pull-down and luciferase assays showed that circ_CCDC66 could competitively bind to microRNA (miR)-342-3p, therefore restoring the expression of metadherin (MTDH) mRNA, a target transcript of miR-342-3p. Suppression of circ_CCDC66 in the M2-EVs or specific knockdown of MTDH in CRC significantly blocked the growth and mobility of CRC cells. However, miR-342-3p inhibition restored the malignant phenotype of cancer cells. Moreover, the MTDH knockdown was found to increase the cytotoxicity of CD8+ T and reduce the protein level of the immune checkpoint PDL1 in CRC cells. In summary, this study reveals that the M2-EVs augment immune evasion and development of CRC by delivering circ_CCDC66 and restoring the MTDH level.

Zinc Finger E-Box Binding Homeobox Family: Non-Coding RNA and Epigenetic Regulation in Gliomas

Gliomas are the most common malignant brain tumours. Among them, glioblastoma (GBM) is a grade four tumour with a median survival of approximately 15 months and still limited treatment options. Although a classical epithelial to mesenchymal transition (EMT) is not the case in glioma due to its non-epithelial origin, the EMT-like processes may contribute largely to the aggressive and highly infiltrative nature of these tumours, thus promoting invasive phenotype and intracranial metastasis. To date, many well-known EMT transcription factors (EMT-TFs) have been described with clear, biological functions in glioma progression. Among them, EMT-related families of molecules such as SNAI, TWIST and ZEB are widely cited, well-established oncogenes considering both epithelial and non-epithelial tumours. In this review, we aimed to summarise the current knowledge with a regard to functional experiments considering the impact of miRNA and lncRNA as well as other epigenetic modifications, with a main focus on ZEB1 and ZEB2 in gliomas. Although we explored various molecular interactions and pathophysiological processes, such as cancer stem cell phenotype, hypoxia-induced EMT, tumour microenvironment and TMZ-resistant tumour cells, there is still a pressing need to elucidate the molecular mechanisms by which EMT-TFs are regulated in gliomas, which will enable researchers to uncover novel therapeutic targets as well as improve patients' diagnosis and prognostication.

UCHL1 acts as a potential oncogene and affects sensitivity of common anti-tumor drugs in lung adenocarcinoma

Background

Lung adenocarcinoma is the leading cause of cancer death worldwide. Recently, ubiquitin C-terminal hydrolase L1 (UCHL1) has been demonstrated to be highly expressed in many tumors and plays the role of an oncogene. However, the functional mechanism of UCHL1 is unclear in lung adenocarcinoma progression.

Methods

We analyzed the differential expression of the UCHL1 gene in lung adenocarcinoma and normal lung tissues, and the correlation between the UCHL1 gene and prognosis was also analyzed by the bioinformatics database TCGA. Meanwhile, we detected and analyzed the expression of UCHL1 and Ki-67 protein in a tissue microarray (TMA) containing 150 patients with lung adenocarcinoma by immunohistochemistry (IHC) and clinicopathological characteristics by TCGA database. In vitro experiments, we knocked down the UCHL1 gene of A549 cells and detected the changes in cell migration, invasion, and apoptosis. At the same time, we analyzed the effect of UCHL1 on anti-tumor drug sensitivity of lung adenocarcinoma by a bioinformatics database. In terms of the detection rate of lung adenocarcinoma indicators, we analyzed the impact of UCHL1 combined with common clinical indicators on the detection rate of lung adenocarcinoma through a bioinformatics database.

Results

In this study, the analysis of UCHL1 protein expression in lung adenocarcinoma proved that obviously higher UCHL1 protein level was discovered in lung adenocarcinoma tissues. The expression of UCHL1 was closely related to poor clinical outcomes. Interestingly, a significantly positive correlation between the expression of UCHL1 and Ki-67-indicated UCHL1 was associated with tumor migration and invasion. Through executing loss of function tests, we affirmed that silencing of UCHL1 expression significantly inhibited migration and invasion of lung adenocarcinoma cells in vitro. Furthermore, lung adenocarcinoma cells with silenced UCHL1 showed a higher probability of apoptosis. In terms of the detection rate of lung adenocarcinoma indicators, we discovered UCHL1 could improve the detection rate of clinical lung adenocarcinoma and affect drug sensitivity.

Conclusion

In lung adenocarcinoma, UCHL1 promotes tumor migration, invasion, and metastasis by inhibiting apoptosis and has an important impact on the clinical drug treatment of lung adenocarcinoma. In addition, UCHL1 can improve the detection rate of clinical lung adenocarcinoma. Above all, UCHL1 may be a new marker for the diagnosis of lung adenocarcinoma and provide a new target for the treatment of clinical diseases.