Abstract:Objective To explore the effects and mechanisms of long chain non-coding RNA (lncRNA) LINC00667 on the proliferation, migration and invasion of rheumatoid arthritis synovial fibroblasts (RA-FLS).Methods The model was established in SPF Wistar rats, the synovial tissue of ankle joint was isolated, and the expression of LINC00667 and miR-19a-3p in RA-FLS was detected by quantitative real-time polymerase chain reaction (qRT-PCR). Transfect si-NC, si-LINC00667, miR-NC, miR-19a-3p simulant, si-LINC00667 and anti-miR-NC, si-LINC00667 and anti-miR-19a-3p in RA-FLS, and divide them into si-NC group, si-LINC00667 group, miR-NC group, miR-19a-3p group, si-LINC00667 + anti-miR-NC group and si-LINC00667 + anti-miR-19a-3p group. CCK-8 method was used to detect the proliferation inhibition rate of RA-FLS after different transfections, Transwell method was used to detect cell migration and invasion, and Western blotting was used to detect the expression of E-cadherin and N-cadherin. Double luciferase report verified the targeting relationship between LINC00667 and miR-19a-3p.Results The expression of LINC00667 in synovial tissue of RA model group was 270% of that of normal group, and the expression of miR-19a-3p was 36% that of normal group (P < 0.05). After successful transfection, the inhibition rate of RA-FLS and the expression of E-cadherin protein in the si LINC00667 group were higher than those in the si-NC group, and the number of migration and invasion cells and the expression of N-cadherin protein were lower than those in the si-NC group (P < 0.05). LINC00667 targeted miR-19a-3p. The inhibition rate of RA-FLS and the expression of E-cadherin protein in miR-19a-3p group were higher than those in miR-NC group, while the number of migration and invasion cells and the expression of N-cadherin protein in miR-19a-3p group were lower than those in miR-NC group (P < 0.05). The inhibition rate of RA-FLS and the expression of E-cadherin protein in si-LINC00667 + anti-miR-19a-3p group were lower than those in si-LINC00667 + anti-miR-NC group, while the number of migration and invasion cells and the expression of N-cadherin protein in si-LINC00667 + anti-miR-NC group were higher than those in si-LINC00667 + anti-miR-NC group (P < 0.05).Conclusion LINC00667 can promote the proliferation, migration and invasion of RA-FLS by targeting miR-19a-3p.