CircPDHX promotes prostate cancer cell progression in vitro and tumor growth in vivo via miR-497-5p/ACSL1 axis.

BACKGROUND: Circular RNAs (circRNAs) have been proved could regulate many cancers, including prostate cancer (PCa). In this paper, we reconnoitered the roles of circRNA pyruvate dehydrogenase complex component X (circPDHX) in PCa. METHODS: The circPDHX, microRNA (miR)-497-5p and acyl-CoA synthetase long chain family member 1 (ACSL1) contents were detected by quantitative real-time PCR and Western blot analysis. Cell proliferation was measured by cell counting kit-8 assay, 5-Ethynyl-2'-deoxyuridine assay, and colony formation assay. Cell migration was examined by wound healing assay. The apoptosis was detected by flow cytometry assay. The ELISA kits were applied to quantify the fatty acid metabolites. Furthermore, the interplay between miR-497-5p and circPDHX or ACSL1 was detected by dual-luciferase reporter assay and RIP assay. The role of circPDHX in PCa was supplementary substantiated in vivo. RESULTS: CircPDHX and ACSL1 contents were upregulated, and the miR-497-5p level was downregulated in PCa. CircPDHX deficiency attenuated PCa cell proliferation, migration, and fatty acid metabolites, while intensified cell apoptosis. CircPDHX bound to miR-497-5p to adjust ACSL1. Moreover, miR-497-5p inhibited the PCa progression by regulating ACSL1. In the meantime, circPDHX deficiency repressed PCa tumor growth in vivo. CONCLUSION: CircPDHX stimulated PCa development via miR-497-5p/ACSL1, which presented a new thought for PCa treatment.

Gastrodin promotes the regeneration of peripheral nerves by regulating miR-497/BDNF axis.

BACKGROUND: Gastrodin (GAS), is a kind of phenolic compound extracted from the traditional Chinese herbal medicine Gastrodia elata Blume (GEB). This study was aimed at probing into the protective effect of GAS on peripheral nerve injury (PNI) and the underlying mechanism. METHODS: A rat model with PNI was established, followed by intraperitoneal injection of GAS (20 mg/kg/day). Sciatic nerve function index (SFI) was used to analyze the function of sciatic nerve. The amplitude and latency of compound muscle action potential (CMAP) were examined by electrophysiology. Schwann cells (SCs) were isolated from fetal rats and treated with GAS 200 µg/mL, and H2O2-induced model of oxidative stress injury was established. EdU and Transwell assays were adopted to detect the viability and migration of SCs. Dual-luciferase reporter gene assays were applied to verify the binding site between miR-497 and brain-derived neurotrophic factor (BDNF) 3'UTR. MiR-497 expression was probed by quantitative real-time polymerase chain reaction (qRT-PCR). BDNF, neurofilament-200 (NF-200) and myelin basic protein (MBP) expression levels were detected by Western blotting. Malondialdehyde (MDA) content, superoxide dismutase (SOD) activity, glutathione content (GSH) and catalase (CAT) activity in SCs were also measured. RESULTS: GAS treatment could significantly increase the SFI and amplitude of CMAP, shorten the refractory period, and ameliorate muscle atrophy of the rats with PNI. GAS treatment could markedly restrain miR-497 expression and increase the expression levels of BDNF, NF-200 and MBP in SCs. BDNF was confirmed as the target of miR-497 and BDNF overexpression could reverse the impacts of miR-497 overexpression on the proliferation, migration, and oxidative stress response of SCs. CONCLUSIONS: GAS promotes the recovery of PNI via modulating miR-497 / BDNF axis and inhibiting oxidative stress.

Tanshinone IIA regulates human AML cell proliferation, cell cycle, and apoptosis through miR-497-5p/AKT3 axis.

BACKGROUND: The roots of Salvia miltiorrhiza are used in traditional Chinese medicine (TCM) and have high medicinal value. Tanshinone IIA (Tan IIA) is the active ingredient of Salvia miltiorrhiza which can inhibit the growth of acute leukemia cell lines in vitro, although the mechanism remains unclear. METHODS: CCK-8 assays and BrdU stain were used to evaluate cell proliferation ability. Western blot analysis was used to detect protein expression. miR-497-5p expression level was detected by using qRT-PCR, and Annexin V-FITC/propidium iodide (PI) was used to detect cell apoptosis. RESULTS: Here we reported that Tan IIA could inhibit cell proliferation, induce cell cycle arrest, and promote cell apoptosis in acute myeloid leukemia (AML) cells. Thus, Tan IIA had the anti-cancer activity in AML cell lines, which was likely mediated by up-regulation of miR-497-5p expression. Our data further showed that in AML cells, the same effects were observed with overexpression of miR-497-5p by a miR-497-5p mimic. We demonstrated that Tan IIA could inhibit the expression of AKT3 by up-regulating the expression of miR-497-5p. We subsequently identified that AKT3 was the direct target of miR-497-5p, and that treatment with Tan IIA obviously reversed the effect of treatment with an miR-497-5p inhibitor under harsh conditions. In turn, PCNA expression was increased and cleaved Caspase-3 was suppressed, which contributed to the growth of AML cells. CONCLUSIONS: Our results showed that Tan IIA could inhibit cell proliferation in AML cells through miR-497-5p-mediated AKT3 downregulation pathway.