Objective:To investigate the expression of miR-383(Micro RNA-383)in osteosarcoma cells and to verify whether upregulation of miR-383 can enhance the therapeutic efficacy of bortezomib against osteosarcoma.Methods:Fluorescence in situ hybridization (FISH) was used to detect the expression of miR-383 in osteosarcoma and normal bone tissues. Real-time quantitative polymerase chain reaction (qRT-PCR) was employed to measure the expression of miR-383 in different osteosarcoma cell lines (SaoS-2, HOS, U-2OS, and MG63)and the osteoblast cell line hFOB 1.19.The proliferative capacity of osteosarcoma cells treated with 5 nmol/L and 10 nmol/L bortezomib was assessed using the cell counting kit-8 (CCK-8) with dimethyl sulfoxide (DMSO) as a control. The activity of caspase-3 was also measured. HOS and MG63 cells were treated with DMSO, bortezomib, miR-383 mimics, or negative controls, and the proliferative capacity and apoptosis levels were re-evaluated using CCK-8 and flow cytometry, respectively.Results:FISH results showed that the level of miR-383-5p in osteosarcoma tissues was significantly lower than that in normal bone tissues ( P<0.05). qRT-PCR results indicated that miR-383 levels in osteosarcoma cells (MG63, HOS, Saos-2, U-2OS) were lower than those in osteoblasts (hFOB1.19), with significant differences among different osteosarcoma cell lines(all P<0.05).The lowest levels of miR-383 were observed in HOS and MG63 cells. CCK-8 and caspase-3 activity assays revealed that among the cells treated with DMSO and two doses of bortezomib, HOS and MG63 cells had higher baseline proliferative capacity. Compared with DMSO-treated control cells, cells treated with 5 nmol/L and 10 nmol/L bortezomib exhibited inhibited proliferation (all P<0.05) and increased caspase-3 activity (all P<0.05). The effect of 10 nmol/L bortezomib was stronger than that of 5 nmol/L (all P<0.05). Compared with negative control-transfected cells, osteosarcoma cells (MG63 and HOS) with overexpressed miR-383 showed inhibited proliferation and increased apoptosis levels (all P<0.05). After bortezomib treatment, osteosarcoma cells (MG63 and HOS)with overexpressed miR-383 exhibited reduced proliferative capacity and enhanced apoptosis levels (all P<0.05). Conclusions:miR-383 exerts anticancer effects in osteosarcoma by inhibiting cell proliferation. Its overexpression significantly enhances the therapeutic efficacy of bortezomib, offering a new direction for the treatment strategies of osteosarcoma.

Objective:To investigate the expression of miR-383(Micro RNA-383)in osteosarcoma cells and to verify whether upregulation of miR-383 can enhance the therapeutic efficacy of bortezomib against osteosarcoma.Methods:Fluorescence in situ hybridization (FISH) was used to detect the expression of miR-383 in osteosarcoma and normal bone tissues. Real-time quantitative polymerase chain reaction (qRT-PCR) was employed to measure the expression of miR-383 in different osteosarcoma cell lines (SaoS-2, HOS, U-2OS, and MG63)and the osteoblast cell line hFOB 1.19.The proliferative capacity of osteosarcoma cells treated with 5 nmol/L and 10 nmol/L bortezomib was assessed using the cell counting kit-8 (CCK-8) with dimethyl sulfoxide (DMSO) as a control. The activity of caspase-3 was also measured. HOS and MG63 cells were treated with DMSO, bortezomib, miR-383 mimics, or negative controls, and the proliferative capacity and apoptosis levels were re-evaluated using CCK-8 and flow cytometry, respectively.Results:FISH results showed that the level of miR-383-5p in osteosarcoma tissues was significantly lower than that in normal bone tissues ( P<0.05). qRT-PCR results indicated that miR-383 levels in osteosarcoma cells (MG63, HOS, Saos-2, U-2OS) were lower than those in osteoblasts (hFOB1.19), with significant differences among different osteosarcoma cell lines(all P<0.05).The lowest levels of miR-383 were observed in HOS and MG63 cells. CCK-8 and caspase-3 activity assays revealed that among the cells treated with DMSO and two doses of bortezomib, HOS and MG63 cells had higher baseline proliferative capacity. Compared with DMSO-treated control cells, cells treated with 5 nmol/L and 10 nmol/L bortezomib exhibited inhibited proliferation (all P<0.05) and increased caspase-3 activity (all P<0.05). The effect of 10 nmol/L bortezomib was stronger than that of 5 nmol/L (all P<0.05). Compared with negative control-transfected cells, osteosarcoma cells (MG63 and HOS) with overexpressed miR-383 showed inhibited proliferation and increased apoptosis levels (all P<0.05). After bortezomib treatment, osteosarcoma cells (MG63 and HOS)with overexpressed miR-383 exhibited reduced proliferative capacity and enhanced apoptosis levels (all P<0.05). Conclusions:miR-383 exerts anticancer effects in osteosarcoma by inhibiting cell proliferation. Its overexpression significantly enhances the therapeutic efficacy of bortezomib, offering a new direction for the treatment strategies of osteosarcoma.