ObjectiveTo enhance teaching in postoperative cancer rehabilitation, this study developed an integrative Chinese-Western medicine postoperative oncology rehabilitation system, termed the medical oncology generative pre-trained transformer (MedOncoGPT). By introducing MedOncoGPT as an intelligent assistant, an integrated teaching model combining Chinese and Western medicine was established. The study evaluated its impact on students’ integrative clinical reasoning and practical abilities, providing support for instructional reform in related courses. MethodsUsing teaching resources as the knowledge base, MedOncoGPT was built upon the open-source ChatGLM model and incorporated Low-Rank Adaptation (LoRA) fine-tuning and retrieval-augmented generation (RAG) techniques to address postoperative integrative oncology scenarios. The system was applied in courses and clinical clerkships related to integrative oncology. In alignment with course objectives, a five-stage instructional process—pre-class preparation, in-class inquiry, simulated multidisciplinary consultation, clinical reinforcement, and teaching reflection—was designed to guide students in completing syndrome differentiation, comprehensive assessment, and follow-up planning within real or simulated case contexts. Comparative analyses of student engagement, syndrome differentiation thinking, evidence-based awareness, and interdisciplinary integration skills before and after the teaching reform were conducted using questionnaires, course assessments, classroom observations, and semi-structured interviews. ResultsFollowing the implementation of MedOncoGPT, students demonstrated improved performance in case analysis, prescription formulation, and integrative Chinese-Western medical evaluation compared with those receiving traditional instruction. Classroom participation and the relevance of student inquiries also increased. Self-assessment results indicated high levels of satisfaction with respect to clarity of integrative clinical reasoning, ability to retrieve and apply guideline-based evidence, and awareness of appropriate use of intelligent tools in clinical decision-making. More than 92% of students reported that the system facilitated understanding of abstract theoretical concepts presented in textbooks. Instructors noted that the system helped reduce lesson preparation time, enriched typical case materials and discussion scenarios, and promoted the translation of research findings into classroom teaching. Pilot data showed that, with MedOncoGPT assistance, the mean time for initial syndrome differentiation decreased from 18.4 min to 12.1 min, and the agreement rate increased from 68.3% to 82.5%. In the teaching pilot, the experimental group achieved a higher mean score on the final case analysis assessment than the control group (82.6 vs. 74.3). ConclusionThe integration of MedOncoGPT into teaching on postoperative integrative cancer rehabilitation enabled the establishment of a stable instructional process within existing curricula and enhanced students’ integrative clinical reasoning and evidence-based practice capabilities. The approach demonstrates positive potential for advancing the integration of research, clinical practice, and education and represents a valuable exploratory strategy for instructional reform in courses on integrative Chinese-Western medicine.

ObjectiveTo enhance teaching in postoperative cancer rehabilitation, this study developed an integrative Chinese-Western medicine postoperative oncology rehabilitation system, termed the medical oncology generative pre-trained transformer (MedOncoGPT). By introducing MedOncoGPT as an intelligent assistant, an integrated teaching model combining Chinese and Western medicine was established. The study evaluated its impact on students’ integrative clinical reasoning and practical abilities, providing support for instructional reform in related courses. MethodsUsing teaching resources as the knowledge base, MedOncoGPT was built upon the open-source ChatGLM model and incorporated Low-Rank Adaptation (LoRA) fine-tuning and retrieval-augmented generation (RAG) techniques to address postoperative integrative oncology scenarios. The system was applied in courses and clinical clerkships related to integrative oncology. In alignment with course objectives, a five-stage instructional process—pre-class preparation, in-class inquiry, simulated multidisciplinary consultation, clinical reinforcement, and teaching reflection—was designed to guide students in completing syndrome differentiation, comprehensive assessment, and follow-up planning within real or simulated case contexts. Comparative analyses of student engagement, syndrome differentiation thinking, evidence-based awareness, and interdisciplinary integration skills before and after the teaching reform were conducted using questionnaires, course assessments, classroom observations, and semi-structured interviews. ResultsFollowing the implementation of MedOncoGPT, students demonstrated improved performance in case analysis, prescription formulation, and integrative Chinese-Western medical evaluation compared with those receiving traditional instruction. Classroom participation and the relevance of student inquiries also increased. Self-assessment results indicated high levels of satisfaction with respect to clarity of integrative clinical reasoning, ability to retrieve and apply guideline-based evidence, and awareness of appropriate use of intelligent tools in clinical decision-making. More than 92% of students reported that the system facilitated understanding of abstract theoretical concepts presented in textbooks. Instructors noted that the system helped reduce lesson preparation time, enriched typical case materials and discussion scenarios, and promoted the translation of research findings into classroom teaching. Pilot data showed that, with MedOncoGPT assistance, the mean time for initial syndrome differentiation decreased from 18.4 min to 12.1 min, and the agreement rate increased from 68.3% to 82.5%. In the teaching pilot, the experimental group achieved a higher mean score on the final case analysis assessment than the control group (82.6 vs. 74.3). ConclusionThe integration of MedOncoGPT into teaching on postoperative integrative cancer rehabilitation enabled the establishment of a stable instructional process within existing curricula and enhanced students’ integrative clinical reasoning and evidence-based practice capabilities. The approach demonstrates positive potential for advancing the integration of research, clinical practice, and education and represents a valuable exploratory strategy for instructional reform in courses on integrative Chinese-Western medicine.

Objective To investigate the expression characteristics and clinical diagnostic value of programmed death receptor 1(PD-1)and its corresponding ligand(PD-L1)in patients with acute exacerbation of chronic obstructive pulmonary disease(AECOPD).Methods One hundred and sixty COPD patients who visited Dongzhimen Hospital of Beijing University of Chinese Medicine from April 2024 to November 2024 were included and divided into an acute exacerbation group of 100 cases and a stable group of 60 cases according to the severity of the disease.Additionally,40 healthy volunteers during the same period were recruited as the control group.The general clinical data of the patients were collected.Chronic Obstructive Pulmonary Disease Assessment Test(CAT)and Modified Medical Research Council Dyspnea Questionnaire(mMRC)Scale were used to test the severity of the disease;respiratory function testing was performed and fasting venous blood was collected for serum PD-1 and PD-L1 testing.Pearson correlation was used to analyze the correlation between serum PD-1,PD-L1,CAT,and mMRC,and multiple logistic regression analysis to identify the influencing factors of AECOPD.Receiver operating characteristic(ROC)curve was drawn to evaluate the diagnostic value of serum PD-1 and PD-L1 level for AECOPD.Results Serum PD-1 level in the stable COPD group and AECOPD group was significantly increased compared with that in the control group,while serum PD-L1 level was significantly decreased,showing statistical significance(P<0.05);The level of PD-1 gradually increased with the grading of lung function and the deterioration of AECOPD,with statistical significance(P<0.05);Pearson correlation showed that serum PD-1 level was positively correlated with CAT scores in COPD patients,while negatively with CAT scores,showing statistical significance(P<0.05);Multiple logistic regression analysis showed that elevated levels of serum inter-leukin-6(IL-6),neutrophil to lymphocyte ratio(NLR),and PD-1 were risk factors for AECOPD,while elevated level of PD-L1 was protective factor for AECOPD(P<0.05);ROC curve showed that the levels of PD-1,PD-L1,IL-6,NLR,and the area under the ROC curve(AUC)for their combined prediction of AECOPD diagnosis were 0.884,0.867,0.868,0.802,and 0.995,respectively.Conclusion Serum PD-1 and PD-L1 in AECOPD patients have presented certain expression characteristics,with elevated PD-1 level while decreased PD-L1 level.Both have good clinical diagnostic value for AECOPD.

Objective To compare the effects of dexmedetomidine and midazolam on intraoperative blood pressure and postoperative 90-day outcome of endovascular treatment(EVT)in patients with acute anterior circulation large vessel occlusive stroke.Methods Retrospective consecutive patients with acute anterior circulation large vessel occlusion stroke who received EVT within 24 hours of onset,admitted to the Department of Neurology at the Second People's Hospital of Hefei from January 2024 to February 2025 were included.Patients were divided into the dexmedetomidine group and the midazolam group based on the choice of sedative in EVT.Baseline and clinical data were collected from patients,including sex,age,medical history(hypertension,diabetes,atrial fibrillation,stroke history),smoking history,blood pressure at admission(systolic,diastolic,mean arterial pressure),National Institutes of Health stroke scale(NIHSS)score at admission,trial of Org 10172 in acute stroke treatment(TOAST)classification,and site of vascular occlusion(internal carotid artery,M1 segment of the middle cerebral artery).Procedure related parameters,including intravenous thrombolysis before EVT,intraoperative use of tirofiban,modified thrombolysis in cerebral infarction(mTICI)grade,thrombectomy techniques(stent-retriever thrombectomy,aspiration thrombectomy,combined stent-retriever and aspiration thrombectomy,and other salvage measures),number of thrombectomy,time from onset to revascularization,time from puncture to revascularization,blood pressure during EVT(minimum systolic,minimum diastolic,and minimum mean arterial pressure),and blood pressure at the end of EVT(systolic,diastolic,and mean arterial pressure).The primary outcome was good prognosis at 90 days after EVT(modified Rankin scale score of 0-2 at 90 days),while secondary outcome was＞20％decrease in mean arterial pressure during EVT,early neurological improvement(ENI;a decrease on NIHSS score no less than 8 or a reduction of NIHSS score to 0-1 at 24 hours after EVT),and early neurological deterioration(END;an increase of more than 2 points on the NIHSS at 24 hours after procedure).Safety outcomes included any intracranial hemorrhage within 48 hours after EVT,symptomatic intracranial hemorrhage within 48 hours after EVT(sICH;intracranial hemorrhage confirmed by head CT leading to neurological deterioration,with an increase in NIHSS score of at least 4 points,or the presence of potentially fatal intracranial hemorrhage on head CT),pneumonia within 2 weeks after EVT,and the 90-day mortality after EVT.The baseline and clinical data,EVT conditions,primary outcome,secondary outcome,and safety indicators were compared between the two groups.Univariate Logistic regression analysis was used to screen the variables associated with a decrease in mean arterial pressure＞20％during EVT in patients with acute anterior circulation large vessel occlusive stroke.Variables with P＜0.15 and those considered potentially influential based on clinical experience were included in multivariate Logistic regression analysis to identify predictors of a＞20％decrease in mean arterial pressure during EVT in patients with acute anterior circulation large vessel occlusive stroke.Results A total of 93 patients with acute anterior circulation large vessel occlusive stroke who underwent EVT were included,comprising 51 males and 42 females,aged 34 to 99 years,with an average of(71±13)years old.Among them,63 patients were in the dexmedetomidine group,and 30 patients were in the midazolam group.33 patients showed＞20％decreases in mean arterial pressure during EVT,while 60 patients had ≤20％decreases.(1)Compare with the midazolam group,the proportion of female patients in the dexmedetomidine group was lower(36.5％[23/63]vs.63.3％[19/30],P=0.015),and the age was younger([69±13]years vs.[77±13]years,P=0.005).There were no statistically significant differences in other baseline and clinical data(all P＞0.05).(2)In comparison with the midazolam group,the dexmedetomidine group had a higher proportion of patients with more thrombectomy procedures(1.00[1.00,2.00]times vs.1.00[1.00,1.25]times,P=0.011),END(27.0％[17/63]vs.6.7％[2/30],P=0.023),sICH within 48 hours(19.0％[12/63]vs.3.3％[1/30],P=0.041),and a decrease in mean arterial pressure＞20％during EVT(42.9％[27/63]vs.20.0％[6/30],P=0.031).There were no statistically significant differences in the remaining EVT conditions,primary outcome,secondary outcome,and safety indicators(all P＞0.05).(3)The results of univariate Logistic regression analysis showed that diastolic blood pressure at admission(P=0.002),mean arterial pressure at admission(P=0.009),and dexmedetomidine sedation(P=0.036)were the influencing factors of a decrease＞20％in mean arterial pressure during EVT in patients with acute anterior circulation large vessel occlusion stroke.(4)The results of multivariate Logistic regression analysis showed that dexmedetomidine sedation(OR,3.271,95％CI 1.057-10.126,P=0.040)and higher diastolic blood pressure on admission(OR,1.105,95％CI 1.006-1.213,P=0.037)were independent predictors of a decrease over 20％in mean arterial pressure during EVT in patients with acute anterior circulation large vessel occlusive stroke.Conclusions Dexmedetomidine is an independent predictor of an over 20％decrease in mean arterial pressure during EVT in patients with acute anterior circulation large vessel occlusive stroke,but there is no statistically significant differences in the rate of good neurological function at 90 days and 90-day mortality postoperatively between the two groups.Further prospective randomized controlled studies are needed.

Objective To investigate the clinical efficacy and safety of facilitated percutaneous coronary intervention(PCI)with half-dose recombinant staphylokinase(r-SAK)in patients with ST-segment elevation myocardial infarction(STEMI)who are expected to undergo PCI within 120 minutes.Methods From October 2021 to August 2022,a total of 200 STEMI patients in eight centers were included and randomly assigned in a 1﹕1 ratio to either r-SAK group or control group.Patients received loading doses of aspirin and ticagrelor and intravenous heparin and were randomized to receive an intravenous bolus of either 5 mg r-SAK or normal saline prior to PCI.The outcomes were set as ST-segment resolution(STR)at 60-90 minutes after PCI,the proportion and transition of pathological Q waves on the 5th day after PCI,and the proportion of high-sensitivity cardiac troponin T(hs-cTnT)peaking within 12 hours of onset.The safety outcome was major bleeding events defined as Bleeding Academic Research Consortium(BARC)≥type 3 bleeding during hospitalization.Results Compared with the control group,the r-SAK group had a higher proportion of STR≥70%within 60-90 minutes after PCI(58.3%vs.40.3%,P=0.009);a lower proportion of pathological Q waves(59.1%vs.74.1%,P=0.040);a lower rate of Q wave progression(14.8%vs.43.2%,P＜0.001);a higher rate of Q wave disappearance(12.5%vs.3.7%,P=0.027);and a higher proportion of hs-cTnT peaking within 12 hours of symptom onset[31/40(77.5%)vs.17/33(51.5%),P=0.027].Regarding the safety outcome,no significant difference in BARC≥type 3 bleeding was found between the two groups during hospitalization(P＞0.05).Conclusions For STEMI patients who were expected to undergo primary PCI within 120 minutes of symptom onset,the facilitated PCI with half-dose r-SAK significantly increased the proportion of STR≥70%at 60-90 minutes after PCI,reduced the formation of pathological Q waves,and shortened the time to peak hs-cTnT,without increasing the risk of bleeding,which should be an alternative reperfusion strategy worthy of further study.

Objective To investigate the clinical efficacy and safety of facilitated percutaneous coronary intervention(PCI)with half-dose recombinant staphylokinase(r-SAK)in patients with ST-segment elevation myocardial infarction(STEMI)who are expected to undergo PCI within 120 minutes.Methods From October 2021 to August 2022,a total of 200 STEMI patients in eight centers were included and randomly assigned in a 1﹕1 ratio to either r-SAK group or control group.Patients received loading doses of aspirin and ticagrelor and intravenous heparin and were randomized to receive an intravenous bolus of either 5 mg r-SAK or normal saline prior to PCI.The outcomes were set as ST-segment resolution(STR)at 60-90 minutes after PCI,the proportion and transition of pathological Q waves on the 5th day after PCI,and the proportion of high-sensitivity cardiac troponin T(hs-cTnT)peaking within 12 hours of onset.The safety outcome was major bleeding events defined as Bleeding Academic Research Consortium(BARC)≥type 3 bleeding during hospitalization.Results Compared with the control group,the r-SAK group had a higher proportion of STR≥70%within 60-90 minutes after PCI(58.3%vs.40.3%,P=0.009);a lower proportion of pathological Q waves(59.1%vs.74.1%,P=0.040);a lower rate of Q wave progression(14.8%vs.43.2%,P＜0.001);a higher rate of Q wave disappearance(12.5%vs.3.7%,P=0.027);and a higher proportion of hs-cTnT peaking within 12 hours of symptom onset[31/40(77.5%)vs.17/33(51.5%),P=0.027].Regarding the safety outcome,no significant difference in BARC≥type 3 bleeding was found between the two groups during hospitalization(P＞0.05).Conclusions For STEMI patients who were expected to undergo primary PCI within 120 minutes of symptom onset,the facilitated PCI with half-dose r-SAK significantly increased the proportion of STR≥70%at 60-90 minutes after PCI,reduced the formation of pathological Q waves,and shortened the time to peak hs-cTnT,without increasing the risk of bleeding,which should be an alternative reperfusion strategy worthy of further study.

Objective To compare the effects of dexmedetomidine and midazolam on intraoperative blood pressure and postoperative 90-day outcome of endovascular treatment(EVT)in patients with acute anterior circulation large vessel occlusive stroke.Methods Retrospective consecutive patients with acute anterior circulation large vessel occlusion stroke who received EVT within 24 hours of onset,admitted to the Department of Neurology at the Second People's Hospital of Hefei from January 2024 to February 2025 were included.Patients were divided into the dexmedetomidine group and the midazolam group based on the choice of sedative in EVT.Baseline and clinical data were collected from patients,including sex,age,medical history(hypertension,diabetes,atrial fibrillation,stroke history),smoking history,blood pressure at admission(systolic,diastolic,mean arterial pressure),National Institutes of Health stroke scale(NIHSS)score at admission,trial of Org 10172 in acute stroke treatment(TOAST)classification,and site of vascular occlusion(internal carotid artery,M1 segment of the middle cerebral artery).Procedure related parameters,including intravenous thrombolysis before EVT,intraoperative use of tirofiban,modified thrombolysis in cerebral infarction(mTICI)grade,thrombectomy techniques(stent-retriever thrombectomy,aspiration thrombectomy,combined stent-retriever and aspiration thrombectomy,and other salvage measures),number of thrombectomy,time from onset to revascularization,time from puncture to revascularization,blood pressure during EVT(minimum systolic,minimum diastolic,and minimum mean arterial pressure),and blood pressure at the end of EVT(systolic,diastolic,and mean arterial pressure).The primary outcome was good prognosis at 90 days after EVT(modified Rankin scale score of 0-2 at 90 days),while secondary outcome was＞20％decrease in mean arterial pressure during EVT,early neurological improvement(ENI;a decrease on NIHSS score no less than 8 or a reduction of NIHSS score to 0-1 at 24 hours after EVT),and early neurological deterioration(END;an increase of more than 2 points on the NIHSS at 24 hours after procedure).Safety outcomes included any intracranial hemorrhage within 48 hours after EVT,symptomatic intracranial hemorrhage within 48 hours after EVT(sICH;intracranial hemorrhage confirmed by head CT leading to neurological deterioration,with an increase in NIHSS score of at least 4 points,or the presence of potentially fatal intracranial hemorrhage on head CT),pneumonia within 2 weeks after EVT,and the 90-day mortality after EVT.The baseline and clinical data,EVT conditions,primary outcome,secondary outcome,and safety indicators were compared between the two groups.Univariate Logistic regression analysis was used to screen the variables associated with a decrease in mean arterial pressure＞20％during EVT in patients with acute anterior circulation large vessel occlusive stroke.Variables with P＜0.15 and those considered potentially influential based on clinical experience were included in multivariate Logistic regression analysis to identify predictors of a＞20％decrease in mean arterial pressure during EVT in patients with acute anterior circulation large vessel occlusive stroke.Results A total of 93 patients with acute anterior circulation large vessel occlusive stroke who underwent EVT were included,comprising 51 males and 42 females,aged 34 to 99 years,with an average of(71±13)years old.Among them,63 patients were in the dexmedetomidine group,and 30 patients were in the midazolam group.33 patients showed＞20％decreases in mean arterial pressure during EVT,while 60 patients had ≤20％decreases.(1)Compare with the midazolam group,the proportion of female patients in the dexmedetomidine group was lower(36.5％[23/63]vs.63.3％[19/30],P=0.015),and the age was younger([69±13]years vs.[77±13]years,P=0.005).There were no statistically significant differences in other baseline and clinical data(all P＞0.05).(2)In comparison with the midazolam group,the dexmedetomidine group had a higher proportion of patients with more thrombectomy procedures(1.00[1.00,2.00]times vs.1.00[1.00,1.25]times,P=0.011),END(27.0％[17/63]vs.6.7％[2/30],P=0.023),sICH within 48 hours(19.0％[12/63]vs.3.3％[1/30],P=0.041),and a decrease in mean arterial pressure＞20％during EVT(42.9％[27/63]vs.20.0％[6/30],P=0.031).There were no statistically significant differences in the remaining EVT conditions,primary outcome,secondary outcome,and safety indicators(all P＞0.05).(3)The results of univariate Logistic regression analysis showed that diastolic blood pressure at admission(P=0.002),mean arterial pressure at admission(P=0.009),and dexmedetomidine sedation(P=0.036)were the influencing factors of a decrease＞20％in mean arterial pressure during EVT in patients with acute anterior circulation large vessel occlusion stroke.(4)The results of multivariate Logistic regression analysis showed that dexmedetomidine sedation(OR,3.271,95％CI 1.057-10.126,P=0.040)and higher diastolic blood pressure on admission(OR,1.105,95％CI 1.006-1.213,P=0.037)were independent predictors of a decrease over 20％in mean arterial pressure during EVT in patients with acute anterior circulation large vessel occlusive stroke.Conclusions Dexmedetomidine is an independent predictor of an over 20％decrease in mean arterial pressure during EVT in patients with acute anterior circulation large vessel occlusive stroke,but there is no statistically significant differences in the rate of good neurological function at 90 days and 90-day mortality postoperatively between the two groups.Further prospective randomized controlled studies are needed.

Background: s/Aims: Sarcomatoid hepatocellular carcinoma (HCC) is a rare histological subtype of HCC characterized by extremely poor prognosis; however, its molecular characterization has not been elucidated. Methods: In this study, we conducted an integrated multiomics study of whole-exome sequencing, RNA-seq, spatial transcriptome, and immunohistochemical analyses of 28 paired sarcomatoid tumor components and conventional HCC components from 10 patients with sarcomatoid HCC, in order to identify frequently altered genes, infer the tumor subclonal architectures, track the genomic evolution, and delineate the transcriptional characteristics of sarcomatoid HCCs. Results: Our results showed that the sarcomatoid HCCs had poor prognosis. The sarcomatoid tumor components and the conventional HCC components were derived from common ancestors, mostly accessing similar mutational processes. Clonal phylogenies demonstrated branched tumor evolution during sarcomatoid HCC development and progression. TP53 mutation commonly occurred at tumor initiation, whereas ARID2 mutation often occurred later. Transcriptome analyses revealed the epithelial–mesenchymal transition (EMT) and hypoxic phenotype in sarcomatoid tumor components, which were confirmed by immunohistochemical staining. Moreover, we identified ARID2 mutations in 70% (7/10) of patients with sarcomatoid HCC but only 1–5% of patients with non-sarcomatoid HCC. Biofunctional investigations revealed that inactivating mutation of ARID2 contributes to HCC growth and metastasis and induces EMT in a hypoxic microenvironment. Conclusions We offer a comprehensive description of the molecular basis for sarcomatoid HCC, and identify genomic alteration (ARID2 mutation) together with the tumor microenvironment (hypoxic microenvironment), that may contribute to the formation of the sarcomatoid tumor component through EMT, leading to sarcomatoid HCC development and progression.

Background: s/Aims: Sarcomatoid hepatocellular carcinoma (HCC) is a rare histological subtype of HCC characterized by extremely poor prognosis; however, its molecular characterization has not been elucidated. Methods: In this study, we conducted an integrated multiomics study of whole-exome sequencing, RNA-seq, spatial transcriptome, and immunohistochemical analyses of 28 paired sarcomatoid tumor components and conventional HCC components from 10 patients with sarcomatoid HCC, in order to identify frequently altered genes, infer the tumor subclonal architectures, track the genomic evolution, and delineate the transcriptional characteristics of sarcomatoid HCCs. Results: Our results showed that the sarcomatoid HCCs had poor prognosis. The sarcomatoid tumor components and the conventional HCC components were derived from common ancestors, mostly accessing similar mutational processes. Clonal phylogenies demonstrated branched tumor evolution during sarcomatoid HCC development and progression. TP53 mutation commonly occurred at tumor initiation, whereas ARID2 mutation often occurred later. Transcriptome analyses revealed the epithelial–mesenchymal transition (EMT) and hypoxic phenotype in sarcomatoid tumor components, which were confirmed by immunohistochemical staining. Moreover, we identified ARID2 mutations in 70% (7/10) of patients with sarcomatoid HCC but only 1–5% of patients with non-sarcomatoid HCC. Biofunctional investigations revealed that inactivating mutation of ARID2 contributes to HCC growth and metastasis and induces EMT in a hypoxic microenvironment. Conclusions We offer a comprehensive description of the molecular basis for sarcomatoid HCC, and identify genomic alteration (ARID2 mutation) together with the tumor microenvironment (hypoxic microenvironment), that may contribute to the formation of the sarcomatoid tumor component through EMT, leading to sarcomatoid HCC development and progression.

Background: s/Aims: Sarcomatoid hepatocellular carcinoma (HCC) is a rare histological subtype of HCC characterized by extremely poor prognosis; however, its molecular characterization has not been elucidated. Methods: In this study, we conducted an integrated multiomics study of whole-exome sequencing, RNA-seq, spatial transcriptome, and immunohistochemical analyses of 28 paired sarcomatoid tumor components and conventional HCC components from 10 patients with sarcomatoid HCC, in order to identify frequently altered genes, infer the tumor subclonal architectures, track the genomic evolution, and delineate the transcriptional characteristics of sarcomatoid HCCs. Results: Our results showed that the sarcomatoid HCCs had poor prognosis. The sarcomatoid tumor components and the conventional HCC components were derived from common ancestors, mostly accessing similar mutational processes. Clonal phylogenies demonstrated branched tumor evolution during sarcomatoid HCC development and progression. TP53 mutation commonly occurred at tumor initiation, whereas ARID2 mutation often occurred later. Transcriptome analyses revealed the epithelial–mesenchymal transition (EMT) and hypoxic phenotype in sarcomatoid tumor components, which were confirmed by immunohistochemical staining. Moreover, we identified ARID2 mutations in 70% (7/10) of patients with sarcomatoid HCC but only 1–5% of patients with non-sarcomatoid HCC. Biofunctional investigations revealed that inactivating mutation of ARID2 contributes to HCC growth and metastasis and induces EMT in a hypoxic microenvironment. Conclusions We offer a comprehensive description of the molecular basis for sarcomatoid HCC, and identify genomic alteration (ARID2 mutation) together with the tumor microenvironment (hypoxic microenvironment), that may contribute to the formation of the sarcomatoid tumor component through EMT, leading to sarcomatoid HCC development and progression.