Objective To study the risk factors of preoperative deep vein thrombosis(DVT)in middle-aged and elderly patients with lower limb fractures,and establish and evaluate the constructed nomogram model.Methods A retrospective analysis was conducted on the clinical data of totally 240 middle-aged and elderly patients with lower limb fractures at Quanzhou First Hospital Affiliated to Fujian Medical University from July 2023 to June 2024.According to whether the patient had DVT before surgery,they were divided into a DVT group of 75 cases and a non DVT group of 165 cases.The differences in clinical data and some labora-tory indicators levels at the time of initial admission,including platelets(PLT),prothrombin time(PT),ac-tive partial thromboplastin time(APTT),fibrinogen(FIB),thrombin time(TT),D-dimer(D-D),total pro-tein(TP),albumin(ALB),triglycerides(TG),cholesterol(CHOL),high-density lipoprotein cholesterol(HDL-C),low density lipoprotein cholesterol(LDL-C)between two groups were compared.Logistic binary regression was used to analyze the risk factors of DVT and a nomogram model was constructed.Receiver oper-ating characteristic(ROC)curve was used to evaluate the diagnostic efficacy of various risk factors and nomo-gram model in screening DVT.Results Compared age and D-D levels of the DVT group were significantly higher(P＜0.001),while the levels of APTT,TP and ALB were significantly lower(P＜0.05),and the pro-portion of DVT combined with internal diseases and the proportion of fractures in the femur were significantly higher(P＜0.001).The above-mentioned differential indicators were all single risk factors for DVT.ROC curve analysis showed that except for comorbidities of internal medicine,all other risk factors could effectively screen for DVT(P＜0.05),the area under the curve(AUC)was 0.573-0.706,and the constructed nomo-gram model could effectively improve AUC to 0.797.Conclusion The nomogram model constructed based on single risk factors for DVT in this study is helpful for clinical assessment of the risk of DVT occurrence in pa-tients at the early stage of admission,intuitively and effectively.

Background and purpose:Long non-coding RNA(lncRNA)LINC01410,with a length of 647 bp,participates in a variety of tumor biological processes.However,the role and mechanism of LINC01410 involved in esophageal squamous cell carcinoma(ESCC)remain unclear.This study aimed to explore the potential mechanism of LINC01410 promoting ESCC proliferation and invasion,to provide a potential prognostic indicator and therapeutic target for individuals with ESCC.Methods:Gene Expression Profiling Interactive Analysis 2(GEPIA2)databases were used to analyze the expression of LINC01410 and overall survival in esophageal squamous cell carcinoma data set in the Cancer Genome Atlas(TCGA).Gene Set Enrichment Analysis(GSEA)was performed to identify the underlying signaling pathways involved in the biological effects of LINC01410 in ESCC.A total of 62 pairs of ESCC tissues and paracancerous tissues from ESCC patients who underwent radical surgery in the Department of Thoracic Surgery at the First Affiliated Hospital of Xinxiang Medical College and the First People's Hospital of Pingdingshan City from January 2020 to December 2021 were collected.This project has been approved by the Hospital Ethics Committee(First Affiliated Hospital of Xinxiang Medical College,No.2018036;First People's Hospital of Pingdingshan City,No.2019-018).The expression of LINC01410 in ESCC tissues was detected by real-time fluorescence quantitative polymerase chain reaction(RTFQ-PCR).We transfected EC109 cells with LV-NC or LV-over/LINC01410 and EC9706 cells with shRNA-NC or shRNA-LINC01410.Stable transfected cells(EC109/NC,EC109/OE,EC9706/NC and EC9706/KD)were selected in primary cell culture medium containing puromycin.The expression of LINC01410 was detected by RTFQ-PCR.The impact of LINC01410 on ESCC cell proliferation was determined by 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT)and colony formation assays.The effect of LINC01410 on ESCC cell invasion was detected by transwell migration assay.T cell factor/lymphoid enhancer factor 1(TCF/LEF1)luciferase reporter assay was performed to validate the effect of LINC01410 on the activity of canonical Wnt/β-catenin signaling pathway.The expressions of Wnt/β-catenin and epithelial-mesenchymal transition(EMT)signal pathway related proteins in ESCC cells were detected by Western blot.Results:By analyzing the LINC01410 expression from ESCC samples in TCGA by GEPIA2,we found LINC01410 was consistently increased in ESCC tumors compared with normal tissues(P＜0.05),and high LINC01410 expression was associated with poorer overall survival(OS).RTFQ-PCR assay showed that expressions of LINC01410 were higher in esophageal cancer tissues and esophageal cancer cells(EC109 and EC9706)than in precancerous tissues and HEEC cells(P＜0.05).The expression level of LINC01410 was significantly correlated with invasion range,lymph node metastasis and TNM stage in ESCC patients(P＜0.01).LINC01410 expression was also upregulated in EC109/OE,however the expression of LINC01410 in EC9706/KD was decreased(P＜0.01).MTT assay showed overexpression of LINC01410 increased the viability of EC109 cells,while knockdown of LINC01410 decreased the viability of EC9706 cells(P＜0.01).Colony formation assay indicated that overexpression of LINC01410 enhanced the clonogenic ability of ESCC cells,while knockdown of LINC01410 reduced colony formation(P＜0.01).Transwell migration assay showed that LINC01410 overexpression drastically increased the number of migratory cells,while silencing of LINC01410 suppressed the migration in EC9706 cells(P＜0.01).GSEA revealed that Wnt/β-catenin and EMT pathways were significantly enriched in ESCC samples with a high level of LINC01410.TCF/LEF1 luciferase reporter assay showed higher levels of Wnt-dependent activities were observed in EC109/OE cells,whereas silenced LINC01410 in EC9706 cells led to contrary results(P＜0.01).Western blot analysis showed that overexpression of LINC01410 in EC109 cell significantly increased the expression levels of N-cadherin,β-catenin,cyclin D1,c-Myc and decreased E-cadherin expression,while knockdown LINC01410 resulted in opposite results.Conclusion:LINC01410 promotes proliferation and metastasis of ESCC,which might be caused by activation of Wnt/β-catenin and EMT signaling pathways.

Objective:To develop an ex vivo normothermic mechanical perfusion(NMP)and compare the effect of air-oxygenated NMP versus oxygen-oxygenated NMP on reducing renal injury from donor after cardiac death(DCD).Methods:All kidneys from DCD rats were subjected to 30 min in situ warm ischemia after cardiac attest.And harvested kidneys were stored for 8h under static cold preservation after NMP for 2h.In experimental groups, kidneys were subjected to either air-oxygenated NMP(group A, n=6)or oxygen-oxygenated NMP(group O, n=6). Sham operation(group C, n=6)and DCD kidneys under static cold preservation without NMP(group SCS, n=6)were employed as controls.The evaluation parameters included creatinine(Cr), aspartate amino transferase(AST)and lactate dehydrogenase(LDH)in perfusate, pathological changes by hematoxylin-eosin(HE)staining, histological criteria, expressions of myeloperoxidase and intercellular adhesion molecular-1(ICAM-1)by immunohistochemistry and Western blot, tumor necrosis factor-alpha(TNF-α)and interleukin-6(IL-6)by enzyme-linked immunoadsorbent assay and level of malondialdehyde(MDA)by thiobarbital method and activity of superoxide dismutase(SOD)by WST-8 in renal tissues.Differences between two groups were analyzed by two-tailed unpaired Student's test and differences among more than two groups by one-way ANOVA.Results:Renal arterial oxygen tensions in NMP perfusate were(576.3±68.2)mmHg with oxygen-oxygenation and(137.0±39.1)mmHg with air-oxygenation.There was significant difference( P<0.05). The pathological injury scores in groups SCS, O and A by HE staining were(7.0±0.1), (5.0±0.9)and(2.5±0.5); injury scores and the expressions of renal proximal tubular epithelial cell vacuolar degeneration in groups O and A were lower than those in group SCS( P<0.05)and injury score in group A was lower than group O( P<0.05). In perfusate, the levels of △Cr, △AST and △LDH in groups O and A were(43.9±52.8)μmol/L and(12.6±3.5)μmol/L, (532.3±52.8)U/L and(49.1±50.4)U/L and(9998.0±2014.4)U/L and(1477.0±810.4)U/L.There were significant differences( P<0.05). In perfused kidneys, the MDA level and SOD activity in groups O and A were(0.192±0.018)mmol/g, (0.162±0.023)mmol/g, (0.6±0.3)×10 3 U/g, (1.7±0.4)×10 3 U/g; TNF-α and IL-6 levels in groups O and A were(124.376±19.635)and(89.331±13.123)ng/g, and(4.038±1.026)×10 3 and(1.774±0.518)×10 3 ng/g.After air-oxygenated NMP, lower renal damage indices were characterized by a lower MDA level and a higher SOD activity, the lower levels of TNF-α and IL-6 and the lower expressions of MPO and ICAM-1 than those in oxygen-oxygenated NMP( P<0.05). Conclusions:NMP with air-oxygenation mimics renal perfusion under physiological conditions and decreases oxidative stress and inflammation injury.It may confer a better retrieval in DCD kidney against warm ischemia injury.

Objective:To investigate the effects of osimertinib on proliferation, migration and invasion of procollagen-lysine 2-oxoglutarate 5-dioxygenase 2 (PLOD2) overexpressing HCC827 cells and explore the potential mechanism of PLOD2 induced osimertinib resistance.Methods:We transfected HCC827 cells with LV-vector and LV-over/PLOD2. The expression of PLOD2 was detected by quantitative real time polymerase chain reaction (qRT-PCR) and western blotting. The effects of osimertinib on the proliferation of HCC827-vector and HCC827-PLOD2 cells were evaluated by 3-(4, 5-dimethyl-2-thiazolyl)-2, 5-diphenyl-2H tetrazolium bromide (MTT) assay. The effects of osimertinib on the migration and invasion of HCC827-vector and HCC827-PLOD2 cells were determined by Transwell assays. The expressions of E-cadherin and vimentin in cells were detected by immunofluorescence (IF). The expressions of epithelial-mesenchymal transition (EMT), FAK-PI3K/AKT and MAPK signal pathway related proteins were detected by western blotting.Results:The MTT assay showed that HCC827-PLOD2 cells were hyposensitive to osimertinib. The 50% inhibitory concentration (IC 50) and resistance index of osimertinib for HCC827-PLOD2 cells was over 1 000 nmol/L and over 100, respectively. The result of wound healing assay showed that the migration distance of HCC827-PLOD2 was about (2.13±0.21) fold changes as that of HCC827-vector cells. The result of Transwell assay showed that the numbers of HCC827-PLOD2 passing through the matrix membrane were (212.78±10.43), significantly higher than (101.32±12.52) of HCC827-vector cells ( P<0.01). The result of IF showed that compared with HCC827-vector cells, the expression of E-cadherin was down-regulated while vimentin was up-regulated in HCC827-PLOD2 cells. Osimertinb downregulated E-cadherin and upregulated vimentin expression in HCC827-vector cells but had limited effect in HCC827-PLOD2 cells. The result of western blotting showed that PLOD2 significantly increased vimentin expression level while decreased E-cadherin expression level. Osimertinib inhibited the expression of p-EGFR, but did not affect the expressions of PLOD2, p-FAK, p-AKT, p-ERK, vimentin and E-cadherin in HCC827-PLOD2 cells. Conclusion:PLOD2 confers resistance to osimertinib in HCC827 cells by regulating EMT, FAK-PI3K/AKT and MAPK signal pathways.

Objective:To explore the potential mechanism of sorafenib resistance associated long non-coding RNA (lncRNA-SRLR) promoted invasion and metastasis in U2OS osteosarcoma cells.Methods:We transfected U2OS cells with negative control lentivirus (LV-NC) or lncRNA-SRLR overexpressed lentivirus (LV-over/SRLR) particles. LV-NC and LV-over/SRLR stable transfected cells (U20S/NC and U20S/SRLR) were selected by primary cell culture medium containing puromycin. The mRNA expressions of lncRNA-SRLR and procollagen-lysine, procollagen-lysine 2-oxoglutarate 5-dioxygenase 2 (PLOD2) were detected by quantitative real-time polymerase chain reaction (qRT-PCR). The effect of lncRNA-SRLR on the invasion of U2OS cells were determined by wound-healing assay and Transwell migration assay. The effect of SRLR on the interleukin-6 (IL-6) secretion of U2OS cells was evaluated by enzyme-linked immunosorbent assay (ELISA) analysis. The subcellular distribution of SRLR in U2OS cells was detected by fluorescence in situ hybridization (FISH) analysis.The expression of PLOD2 in cells was detected by immunofluorescence (IF). The expressions of PLOD2 and focal adhesion kinase (FAK)/signal transducer and activator of transcription 3 (STAT3) signal pathway related proteins in U2OS/NC and U2OS/SRLR cells were detected by western blotting.Results:qRT-PCR assay showed that mRNA expressions of lncRNA-SRLR and PLOD2 in U2OS/SRLR cells were (3 964.97±0.05) and (2.77±0.11), respectively, significantly higher than those in U2OS/NC cells ( P<0.001 or P<0.01). The results of wound-healing and Transwell migration assay showed that over-expression of SRLR markedly promoted the invasion ability of U2OS cells ( P<0.05). The result of ELISA analysis showed that the IL-6 secretions in U2OS/NC or U2OS/SRLR cells were (125.38±11.22) pg/ml or (119.97±13.43) pg/ml, without statistical significance ( P>0.05). The subcellular distribution assay revealed that lncRNA-SRLR is predominately located in the nucleus. The result of IF showed that compared with U2OS/NC cells, the expression of PLOD2 was up-regulated in U2OS/SRLR cells. The result of western blotting showed that over-expression of SRLR significantly increased the expression levels of PLOD2, phosphorylation (p)-FAK and p-STAT3 in U2OS cells ( P<0.01). Conclusion:lncRNA-SRLR promotes invasion and metastasis of osteosarcoma by activating PLOD2-FAK/STAT3 signal axis.

Objective:To investigate the effects of osimertinib on proliferation, migration and invasion of procollagen-lysine 2-oxoglutarate 5-dioxygenase 2 (PLOD2) overexpressing HCC827 cells and explore the potential mechanism of PLOD2 induced osimertinib resistance.Methods:We transfected HCC827 cells with LV-vector and LV-over/PLOD2. The expression of PLOD2 was detected by quantitative real time polymerase chain reaction (qRT-PCR) and western blotting. The effects of osimertinib on the proliferation of HCC827-vector and HCC827-PLOD2 cells were evaluated by 3-(4, 5-dimethyl-2-thiazolyl)-2, 5-diphenyl-2H tetrazolium bromide (MTT) assay. The effects of osimertinib on the migration and invasion of HCC827-vector and HCC827-PLOD2 cells were determined by Transwell assays. The expressions of E-cadherin and vimentin in cells were detected by immunofluorescence (IF). The expressions of epithelial-mesenchymal transition (EMT), FAK-PI3K/AKT and MAPK signal pathway related proteins were detected by western blotting.Results:The MTT assay showed that HCC827-PLOD2 cells were hyposensitive to osimertinib. The 50% inhibitory concentration (IC 50) and resistance index of osimertinib for HCC827-PLOD2 cells was over 1 000 nmol/L and over 100, respectively. The result of wound healing assay showed that the migration distance of HCC827-PLOD2 was about (2.13±0.21) fold changes as that of HCC827-vector cells. The result of Transwell assay showed that the numbers of HCC827-PLOD2 passing through the matrix membrane were (212.78±10.43), significantly higher than (101.32±12.52) of HCC827-vector cells ( P<0.01). The result of IF showed that compared with HCC827-vector cells, the expression of E-cadherin was down-regulated while vimentin was up-regulated in HCC827-PLOD2 cells. Osimertinb downregulated E-cadherin and upregulated vimentin expression in HCC827-vector cells but had limited effect in HCC827-PLOD2 cells. The result of western blotting showed that PLOD2 significantly increased vimentin expression level while decreased E-cadherin expression level. Osimertinib inhibited the expression of p-EGFR, but did not affect the expressions of PLOD2, p-FAK, p-AKT, p-ERK, vimentin and E-cadherin in HCC827-PLOD2 cells. Conclusion:PLOD2 confers resistance to osimertinib in HCC827 cells by regulating EMT, FAK-PI3K/AKT and MAPK signal pathways.

Objective:To explore the potential mechanism of sorafenib resistance associated long non-coding RNA (lncRNA-SRLR) promoted invasion and metastasis in U2OS osteosarcoma cells.Methods:We transfected U2OS cells with negative control lentivirus (LV-NC) or lncRNA-SRLR overexpressed lentivirus (LV-over/SRLR) particles. LV-NC and LV-over/SRLR stable transfected cells (U20S/NC and U20S/SRLR) were selected by primary cell culture medium containing puromycin. The mRNA expressions of lncRNA-SRLR and procollagen-lysine, procollagen-lysine 2-oxoglutarate 5-dioxygenase 2 (PLOD2) were detected by quantitative real-time polymerase chain reaction (qRT-PCR). The effect of lncRNA-SRLR on the invasion of U2OS cells were determined by wound-healing assay and Transwell migration assay. The effect of SRLR on the interleukin-6 (IL-6) secretion of U2OS cells was evaluated by enzyme-linked immunosorbent assay (ELISA) analysis. The subcellular distribution of SRLR in U2OS cells was detected by fluorescence in situ hybridization (FISH) analysis.The expression of PLOD2 in cells was detected by immunofluorescence (IF). The expressions of PLOD2 and focal adhesion kinase (FAK)/signal transducer and activator of transcription 3 (STAT3) signal pathway related proteins in U2OS/NC and U2OS/SRLR cells were detected by western blotting.Results:qRT-PCR assay showed that mRNA expressions of lncRNA-SRLR and PLOD2 in U2OS/SRLR cells were (3 964.97±0.05) and (2.77±0.11), respectively, significantly higher than those in U2OS/NC cells ( P<0.001 or P<0.01). The results of wound-healing and Transwell migration assay showed that over-expression of SRLR markedly promoted the invasion ability of U2OS cells ( P<0.05). The result of ELISA analysis showed that the IL-6 secretions in U2OS/NC or U2OS/SRLR cells were (125.38±11.22) pg/ml or (119.97±13.43) pg/ml, without statistical significance ( P>0.05). The subcellular distribution assay revealed that lncRNA-SRLR is predominately located in the nucleus. The result of IF showed that compared with U2OS/NC cells, the expression of PLOD2 was up-regulated in U2OS/SRLR cells. The result of western blotting showed that over-expression of SRLR significantly increased the expression levels of PLOD2, phosphorylation (p)-FAK and p-STAT3 in U2OS cells ( P<0.01). Conclusion:lncRNA-SRLR promotes invasion and metastasis of osteosarcoma by activating PLOD2-FAK/STAT3 signal axis.

Objective: To test the effect of metastasis associated in lung adenocarcinoma transcript 1 (MALAT1) and/or osimertinib on the proliferation and apoptosis of HCC827 cells, and explore the potential mechanism of MALAT1 induced resistance to osimertinib. Methods: We transfected HCC827 cells with LV-vector or LV-over/MALAT1. Stable transfected cells (HCC827/Vector, HCC827/MALAT1) were selected by adding puromycin. HCC827/MALAT1 cells were further transfected with the shRNA-negative control (NC) or shRNA-human epidermal growth factor receptor 3 (ERBB3) plasmid. The effects of overexpression of MALAT1, knockdown of ERBB3 and/or osimertinib on the proliferation of HCC827 cells were evaluated by 3-(4, 5-dimethyl-2-thiazolyl)-2, 5-diphenyl-2H tetrazolium bromide (MTT) assay. Cell apoptosis induced by MALAT1 overexpression, knockdown of ERBB3 and/or osimertinib treatment were analyzed by flow cytometry analysis. The expressions of EGFR and ERBB3 signal pathway related proteins in HCC827 cells treated with overexpression of MALAT1, knockdown of ERBB3 and/or osimertinib treatment were detected by western blot. Results: The MTT assay showed that sensitivity to osimertinib of HCC827/MALAT1 cells were significantly repressed. The 50% inhibitive concentration (IC₅₀) of osimertinib >4 000 nmol/L in HCC827/MALAT1 cells. However, knockdown of ERBB3 facilitated the anti-proliferation effect of osimertinib, and the IC₅₀ of osimertinib in shRNA-ERBB3 cells was (17.27±3.21) nmol/L. The results of flow cytometry analysis showed that the apoptotic rate of HCC827/MALAT1 cells induced by 10 nmol/L osimertinib was (8.38±0.92)%, significantly lower than (27.17±5.83)% of knockdown of ERBB3 (P<0.01). Western blotting showed that the expression of p-ERBB3, p-AKT and p-extracellular regulated protein kinases (ERK) in HCC827/MALAT1 cells was markedly up-regulated, while the expression of p-epithelial growth factor receptor (EGFR) was inhibited. The expressions of p-ERBB3, p-AKT and p-ERK were marginally affected by osimertinb. However, osimertinib downregulated the expressions of p-EGFR, p-ERBB3, p-AKT and p-ERK in ERBB3 deleted cells. Conclusions MALAT1 confers resistance to osimertinb in HCC827 cells by activating of the ERBB3/PI3K/AKT and ERBB3/MAPK/ERK signaling pathways.

Objective To test the effect of metastasis associated in lung adenocarcinoma transcript 1 ( MALAT1) and／or osimertinib on the proliferation and apoptosis of HCC827 cells, and explore the potential mechanism of MALAT1 induced resistance to osimertinib. Methods We transfected HCC827 cells with LV?vector or LV?over／MALAT1. Stable transfected cells ( HCC827／Vector, HCC827／MALAT1) were selected by adding puromycin. HCC827／MALAT1 cells were further transfected with the shRNA?negative control ( NC) or shRNA?human epidermal growth factor receptor 3 ( ERBB3 ) plasmid. The effects of overexpression of MALAT1, knockdown of ERBB3 and／or osimertinib on the proliferation of HCC827 cells were evaluated by 3?(4,5?dimethyl?2?thiazolyl)?2,5?diphenyl?2H tetrazolium bromide ( MTT) assay. Cell apoptosis induced by MALAT1 overexpression, knockdown of ERBB3 and／or osimertinib treatment were analyzed by flow cytometry analysis. The expressions of EGFR and ERBB3 signal pathway related proteins in HCC827 cells treated with overexpression of MALAT1, knockdown of ERBB3 and／or osimertinib treatment were detected by western blot. Results The MTT assay showed that sensitivity to osimertinib of HCC827／MALAT1 cells were significantly repressed. The 50% inhibitive concentration (IC50 ) of osimertinib ＞4 000 nmol／L in HCC827／MALAT1 cells.However, knockdown of ERBB3 facilitated the anti?proliferation effect of osimertinib, and the IC50 of osimertinib in shRNA?ERBB3 cells was (17.27±3.21) nmol／L. The results of flow cytometry analysis showed that the apoptotic rate of HCC827／MALAT1 cells induced by 10 nmol／L osimertinib was (8.38±0.92)%, significantly lower than ( 27.17± 5.83)% of knockdown of ERBB3 ( P＜0.01). Western blotting showed that the expression of p?ERBB3, p?AKT and p?extracellular regulated protein kinases ( ERK) in HCC827／MALAT1 cells was markedly up?regulated, while the expression of p?epithelial growth factor receptor (EGFR) was inhibited. The expressions of p?ERBB3, p?AKT and p?ERK were marginally affected by osimertinb. However, osimertinib downregulated the expressions of p?EGFR, p?ERBB3, p?AKT and p?ERK in ERBB3 deleted cells. Conclusions MALAT1 confers resistance to osimertinb in HCC827 cells by activating of the ERBB3／PI3K／AKT and ERBB3／MAPK／ERK signaling pathways.

Objective To test the effect of metastasis associated in lung adenocarcinoma transcript 1 ( MALAT1) and／or osimertinib on the proliferation and apoptosis of HCC827 cells, and explore the potential mechanism of MALAT1 induced resistance to osimertinib. Methods We transfected HCC827 cells with LV?vector or LV?over／MALAT1. Stable transfected cells ( HCC827／Vector, HCC827／MALAT1) were selected by adding puromycin. HCC827／MALAT1 cells were further transfected with the shRNA?negative control ( NC) or shRNA?human epidermal growth factor receptor 3 ( ERBB3 ) plasmid. The effects of overexpression of MALAT1, knockdown of ERBB3 and／or osimertinib on the proliferation of HCC827 cells were evaluated by 3?(4,5?dimethyl?2?thiazolyl)?2,5?diphenyl?2H tetrazolium bromide ( MTT) assay. Cell apoptosis induced by MALAT1 overexpression, knockdown of ERBB3 and／or osimertinib treatment were analyzed by flow cytometry analysis. The expressions of EGFR and ERBB3 signal pathway related proteins in HCC827 cells treated with overexpression of MALAT1, knockdown of ERBB3 and／or osimertinib treatment were detected by western blot. Results The MTT assay showed that sensitivity to osimertinib of HCC827／MALAT1 cells were significantly repressed. The 50% inhibitive concentration (IC50 ) of osimertinib ＞4 000 nmol／L in HCC827／MALAT1 cells.However, knockdown of ERBB3 facilitated the anti?proliferation effect of osimertinib, and the IC50 of osimertinib in shRNA?ERBB3 cells was (17.27±3.21) nmol／L. The results of flow cytometry analysis showed that the apoptotic rate of HCC827／MALAT1 cells induced by 10 nmol／L osimertinib was (8.38±0.92)%, significantly lower than ( 27.17± 5.83)% of knockdown of ERBB3 ( P＜0.01). Western blotting showed that the expression of p?ERBB3, p?AKT and p?extracellular regulated protein kinases ( ERK) in HCC827／MALAT1 cells was markedly up?regulated, while the expression of p?epithelial growth factor receptor (EGFR) was inhibited. The expressions of p?ERBB3, p?AKT and p?ERK were marginally affected by osimertinb. However, osimertinib downregulated the expressions of p?EGFR, p?ERBB3, p?AKT and p?ERK in ERBB3 deleted cells. Conclusions MALAT1 confers resistance to osimertinb in HCC827 cells by activating of the ERBB3／PI3K／AKT and ERBB3／MAPK／ERK signaling pathways.