Circular RNA circ_0046264 Suppresses Osteosarcoma Progression via microRNA-940/Secreted Frizzled Related Protein 1 Axis.

Circular RNAs (circRNAs) feature prominently in regulating tumor progression. The study aims to investigate the role and mechanism of circ_0046264 in osteosarcoma. In this study, dysregulated circRNAs in osteosarcoma tissues and adjacent tissues were screened out by analyzing circRNA microarray (GSE140256). The expressions of circ_0046264 in 58 osteosarcoma tissues and 4 osteosarcoma cell lines were detected by quantitative real-time polymerase chain reaction. Subsequently, the relationship of circ_0046264 expression level and clinical features were analyzed. Ethyldeoxyuridine assay and Transwell assay were employed to detect cell viability, migration and invasion. Dual-luciferase reporter assay was adopted to confirm the targeting relationships between circ_0046264 and microRNA-940 (miR-940), as well as miR-940 and secreted frizzled related protein 1 (SFRP1). SFRP1 expression was determined by western blot. Here, we demonstrated that circ_0046264 was greatly down-regulated in osteosarcoma and was inversely related to tumor size and Ki67 expression. Functional assays validated that circ_0046264 could restrain the proliferation, migration and invasion. Mechanistically, circ_0046264 could adsorb miR-940 and indirectly modulate SFRP1 expression. Furthermore, the transfection of miR-940 mimics or SFRP1 small interfering RNA could reverse the impact of circ_0046264 overexpression on the growth, migration and invasion of osteosarcoma cells. Taken together, circ_0046264 is a tumor suppressor to inhibit the osteosarcoma progression via modulating the miR-940 / SFRP1 axis.

[Feasibility study on local infiltration anesthesia for postoperative analgesia in patients with hallux valgus].

OBJECTIVE: To evaluate the clinical efficacy of local infiltration anesthesia of ropivacaine combined with compound betamethasone for postoperative analgesia in patients with hallux valgus. METHODS: From September 2019 to December 2020, 48 patients with hallux valgus were treated surgically. According to different postoperative analgesia methods, the patients were divided into combined local infiltration group and intravenous analgesia pump group. There were 24 cases, in the combined local infiltration group including 2 males and 22 females;the age ranged from 21 to 78 years old, with an average of (58.3±7.7) years old;soft tissue release and chevron osteotomy were performed in 15 cases and metatarsophalangeal joint fusion in 9 cases;immediately after operation, 20 ml of ropivacaine combined with compound betamethasone mixed diluent was used for local infiltration anesthesia once. There were 24 patients in intravenous analgesia pump group, including 3 males and 21 females;the age ranged from 23 to 81 years old, with an average of(56.8±8.3) years old;soft tissue release and Chevron osteotomy were performed in 17 cases and metatarsophalangeal joint fusion in 7 cases;immediately after operation, intravenous analgesia pump was used for analgesia. The basic flow was 2 ml / h;the self control dose was 0.5 ml;and the locking time was 15 min. Visual analogue scale (VAS) was recorded at 12, 24, 48 and 72 hours after operation;and the VAS was recorded at 24 hours after operation. The occurrence of adverse drug reactions at 0 to 12 hours, 12 to 24 hours and 24 to 48 hours after operation were recorded;and the healing of incision was recorded. RESULTS: All patients were followed up, and the duration ranged from 14 to 17 days, with a mean of (14.60±0.92) days. There was significantdifference in VAS at 12, 24 and 48 hours between the combined local infiltration group and the intravenous analgesia pump group(P<0.05). There was no significant difference in VAS between the two groups 72 hours after operation (P>0.05). There was no significant difference in the number of adverse drug reactions between the two groups at 0 to 12 hours after operation (P>0.05);there was significant difference in the number of adverse drug reactions 12 to 24 hours after operation (P<0.05). No adverse drug reactions occurred in both groups 24 to 48 hours after operation. There was no significant difference in the grade of knife edge healing between the two groups after suture removal (P>0.05). CONCLUSION: Compared with intravenous analgesia pump group, ropivacaine combined with compound betamethasone can significantly reduce postoperative wound pain without increasing adverse drug reactions, and does not increase wound infection.

Long non-coding RNA CCAT2 acts as an oncogene in osteosarcoma through regulation of miR-200b/VEGF.

Background/aim: Colon cancer-associated transcript 2 (CCAT2) is a new lncRNA, which is closely associated with risk of several cancers. The aim of this study was to explore the regulatory mechanism of CCAT2 in osteosarcoma (OSA). Methods: Cells were transfected with si-CCAT2, microRNA (miR)-200b inhibitor and the corresponding controls. Quantitative reverse transcription polymerase chain reaction (qRT-PCR) was used to measure the expression of CCAT2 and miR-200b in OSA tissues and cell lines. CCK8 and bromodeoxyuridine (BrdU) were conducted to examine cell proliferation. Apoptosis was detected by PI/FITC-Annexin V combining with flow cytometric analysis. Migration and invasion were respectively measured through transwell chambers assays. Western blot was used to examine expressions of relative proteins. Results: CCAT2 was highly expressed and miR-200b was lowly expressed in OSA tissues and cell lines. Knockdown of CCAT2 suppressed cell proliferation, migration and invasion but induced apoptosis and up-regulation of miR-200b. miR-200b inhibitor weakened the effect of si-CCAT2 on cell progression and cell mobility. Besides, knockdown of CCAT2 blocked the PI3K/Akt and AMPK pathways through up-regulating miR-200b. Conclusions: The CCAT2/miR-200b/vascular endothelial growth factor (VEGF) axis plays important regulating effect in OSA through the PI3K/Akt and AMPK pathways.