Objective:To investigate the effects of fibroblast growth factor receptor 1(FGFR1)on the resistance of colorectal cancer(CRC)cells to oxaliplatin(OXA).Methods:An OXA-resistant cell line(HCT8/OXA)was established by treating HCT8 CRC cells with low-dose OXA for a long period in vitro.The CCK-8 assay was used to compare the viability of the HCT8 and HCT8/OXA cells after OXA treatment and to exam-ine their resistance to the anticancer drug.Second-generation high-throughput sequencing technology was used to identify differentially ex-pressed genes between the parental and drug-resistant cells.The expression of FGFR1 in the HCT8 and HCT8/OXA cells was detected by Western blot assay.Colony formation and flow cytometric assays were used to determine cell proliferation and apoptosis,respectively.The expression of PI3K/AKT signaling pathway-related proteins was detected using Western blot assay.Results:Compared with the levels in the HCT8 cells,the FGFR1 levels were significantly increased in the HCT8/OXA cells(P<0.01).FGFR1 overexpression in the HCT8 cells increased their drug resistance(P<0.01)and proliferation(NC+OXA:236.67±6.24;FGFR1+OXA:568.33±6.24)and decreased their apoptotic rate after OXA treatment(NC+OXA:27.83±0.85;FGFR1+OXA:17.47±1.25).FGFR1 knockdown in the HCT8/OXA cells reduced their drug resistance(P<0.01)and proliferative ability(Si-NC+OXA:411±8.29;Si-FGFR1+OXA:233.33±20.55)and increased their apoptotic rate(Si-NC+OXA:2.85±0.17;Si-FGFR1+OXA:14.42±0.77).FGFR1 inhibited the activity of the PI3K/AKT signaling pathway and cell apoptosis and improved the proliferation and drug resistance of the CRC cells.By contrast,an activator of the PI3K/AKT pathway blocked the effects of FGFR1 on this sig-naling pathway and drug resistance in the CRC cells.Conclusions:FGFR1 can inhibit the PI3K/AKT signaling pathway and thereby reduce the sensitivity of CRC cells to OXA.

Objective:To investigate the effects of fibroblast growth factor receptor 1(FGFR1)on the resistance of colorectal cancer(CRC)cells to oxaliplatin(OXA).Methods:An OXA-resistant cell line(HCT8/OXA)was established by treating HCT8 CRC cells with low-dose OXA for a long period in vitro.The CCK-8 assay was used to compare the viability of the HCT8 and HCT8/OXA cells after OXA treatment and to exam-ine their resistance to the anticancer drug.Second-generation high-throughput sequencing technology was used to identify differentially ex-pressed genes between the parental and drug-resistant cells.The expression of FGFR1 in the HCT8 and HCT8/OXA cells was detected by Western blot assay.Colony formation and flow cytometric assays were used to determine cell proliferation and apoptosis,respectively.The expression of PI3K/AKT signaling pathway-related proteins was detected using Western blot assay.Results:Compared with the levels in the HCT8 cells,the FGFR1 levels were significantly increased in the HCT8/OXA cells(P<0.01).FGFR1 overexpression in the HCT8 cells increased their drug resistance(P<0.01)and proliferation(NC+OXA:236.67±6.24;FGFR1+OXA:568.33±6.24)and decreased their apoptotic rate after OXA treatment(NC+OXA:27.83±0.85;FGFR1+OXA:17.47±1.25).FGFR1 knockdown in the HCT8/OXA cells reduced their drug resistance(P<0.01)and proliferative ability(Si-NC+OXA:411±8.29;Si-FGFR1+OXA:233.33±20.55)and increased their apoptotic rate(Si-NC+OXA:2.85±0.17;Si-FGFR1+OXA:14.42±0.77).FGFR1 inhibited the activity of the PI3K/AKT signaling pathway and cell apoptosis and improved the proliferation and drug resistance of the CRC cells.By contrast,an activator of the PI3K/AKT pathway blocked the effects of FGFR1 on this sig-naling pathway and drug resistance in the CRC cells.Conclusions:FGFR1 can inhibit the PI3K/AKT signaling pathway and thereby reduce the sensitivity of CRC cells to OXA.

Objective To evaluate the clinical efficacy of invisible orthodontic appliances without brackets for the distal movement of maxillary molars to improve the ability of orthodontists to predict treatment outcomes.Methods Web of Science,Cochrane Library,Embase,PubMed,Wanfang Database,CNKI Database,and VIP Database were searched for studies investigating the efficacy of invisible orthodontic appliances for distal movement of maxillary molars in adult patients and published from database inception to August 1,2023.A total of three researchers screened the studies and evaluated their quality and conducted a meta-analysis of those that met quality standards.Results This study included 13 pre-and postcontrol trials with a total sample size of 281 patients.The meta-analysis revealed no sig-nificant differences in the sagittal or vertical parameters of the jawbone after treatment when compared with those before treatment(P＞0.05).The displacement of the first molar was MD=-2.34,95％CI(-2.83,-1.85);the displacement was MD=-0.95,95％CI(-1.34,-0.56);and the inclination was MD=-2.51,95％CI(-3.56,-1.46).There was a statistically significant difference in the change in sagittal,vertical,and axial tilt of the first molar before and after treatment.After treatment,the average adduction distance of the incisors was MD=-0.82,95％CI(-1.54,-0.09),and the decrease in lip inclination was MD=-1.61,95％CI(-2.86,-0.36);these values were significantly different from those before treat-ment(P＜0.05).Conclusion Invisible orthodontic appliances can effectively move the upper molars in a distal direc-tion and control the vertical position of the molars.When the molars move further away,there is some degree of com-pression and distal tilt movement,which is beneficial for patients with high angles.The sagittal movement of incisors is beneficial for improving the patient's profile.