Neoadjuvant therapy for hepatocellular carcinoma is the frontier and hot topic in the current field of liver cancer research.The fundamental purpose is to reduce the risk of postoperative recurrence through standardized preoperative treatment methods.From the attempts of Transcatheter Arterial Chemoembolization monotherapy for neoadjuvant therapy for hepatocellular carcinoma to systematic treatment represented by"targeted combined with immunotherapy",the latter has become the most promising neoadjuvant strategy due to its high objective response rate and potential to induce pathological complete remission.However,the field still faces challenges such as lack of evidence of overall survival benefit in Phase Ⅲ randomized controlled trials,treatment-related adverse reactions that may lead to delay in surgery,optimal population screening,and timing of surgery.This article aims to briefly discuss the current research status of the application of neoadjuvant therapy in resectable hepatocellular carcinoma,explore relevant diagnosis and treatment concepts,and further understand neoadjuvant therapy.

Background and Aims:Currently,the treatment of hepatocellular carcinoma(HCC)faces significant challenges due to recurrence and metastasis,with tumor immune evasion being one of the key mechanisms underlying these issues.Signal transducer and activator of transcription 3(STAT3),an important transcription factor,is overactivated in many malignancies and is involved in both tumorigenesis and progression,closely associated with immune evasion.Programmed cell death ligand 1(PD-L1),a key immune checkpoint,helps tumor cells evade immune surveillance when its expression is upregulated,thereby suppressing anti-tumor immunity.Studies have shown that STAT3 may activate the MYC signaling pathway through interaction with DNA-activated protein kinase(PRKDC),thereby promoting PD-L1 expression and inducing immune evasion.However,the specific mechanism of the STAT3/PRKDC/MYC axis in HCC remains unclear.This study aims to elucidate the molecular mechanism by which STAT3 regulates PD-L1 expression through the PRKDC/MYC signaling pathway,potentially inducing immune evasion in HCC,with the goal of providing potential targets for HCC immunotherapy.Methods:The expressions of STAT3 in human normal liver cells(HL-7702)and human HCC cells(HuH-7,HepG2)were detected by qRT-PCR and Western blot.Plasmids with STAT3 knockdown(si-STAT3)and PRKDC overexpression(oe-PRKDC),along with their respective negative controls(si-NC,oe-NC),were constructed and transfected into HCC cells(HuH-7)according to the experimental design,with untreated HuH-7 cells as the blank control.Western blot was used to analyze the expression of STAT3,PRKDC,PD-L1,and MYC pathway-related proteins.Cell proliferation,invasion,migration,and apoptosis of HCC cells were assessed by CCK-8,Transwell,wound healing assay,and flow cytometry.After co-culturing HuH-7 cells with human peripheral blood mononuclear cells(hPBMCs),ELISA was used to detect the secretion of the immune regulatory factor interferon γ(IFN-γ).Co-immunoprecipitation and immunofluorescence co-localization were performed to verify the interaction between STAT3 and PRKDC proteins.Results:Results of qRT-PCR and Western blot showed that the mRNA and protein levels of STAT3 were significantly elevated in HCC cells(both P＜0.05).Functional experiments demonstrated that in the si-STAT3 group,HCC cell proliferation,migration,and invasion were significantly weakened,and cell apoptosis was notably increased;the expression of PD-L1 and MYC pathway-related proteins was significantly downregulated;the secretion of IFN-γ was significantly increased after co-culturing with hPBMCs(all P＜0.05).After co-culturing with oe-PRKDC plasmids,the effects of STAT3 knockdown on HCC cells were significantly reversed(all P＜0.05).Scansite 4.0 database analysis revealed that STAT3 and PRKDC have binding sites,and co-immunoprecipitation and immunofluorescence co-localization experiments confirmed the interaction between STAT3 and PRKDC proteins.Conclusion:STAT3 is highly expressed in HCC cells and can promote HCC cell proliferation,migration,invasion,and immune evasion through interaction with PRKDC,suppress cell apoptosis,activate the MYC pathway,and increase PD-L1 expression.The STAT3/PRKDC/MYC axis may serve as a potential target for HCC immunotherapy.

Neoadjuvant therapy for hepatocellular carcinoma is the frontier and hot topic in the current field of liver cancer research.The fundamental purpose is to reduce the risk of postoperative recurrence through standardized preoperative treatment methods.From the attempts of Transcatheter Arterial Chemoembolization monotherapy for neoadjuvant therapy for hepatocellular carcinoma to systematic treatment represented by"targeted combined with immunotherapy",the latter has become the most promising neoadjuvant strategy due to its high objective response rate and potential to induce pathological complete remission.However,the field still faces challenges such as lack of evidence of overall survival benefit in Phase Ⅲ randomized controlled trials,treatment-related adverse reactions that may lead to delay in surgery,optimal population screening,and timing of surgery.This article aims to briefly discuss the current research status of the application of neoadjuvant therapy in resectable hepatocellular carcinoma,explore relevant diagnosis and treatment concepts,and further understand neoadjuvant therapy.

Background and Aims:Currently,the treatment of hepatocellular carcinoma(HCC)faces significant challenges due to recurrence and metastasis,with tumor immune evasion being one of the key mechanisms underlying these issues.Signal transducer and activator of transcription 3(STAT3),an important transcription factor,is overactivated in many malignancies and is involved in both tumorigenesis and progression,closely associated with immune evasion.Programmed cell death ligand 1(PD-L1),a key immune checkpoint,helps tumor cells evade immune surveillance when its expression is upregulated,thereby suppressing anti-tumor immunity.Studies have shown that STAT3 may activate the MYC signaling pathway through interaction with DNA-activated protein kinase(PRKDC),thereby promoting PD-L1 expression and inducing immune evasion.However,the specific mechanism of the STAT3/PRKDC/MYC axis in HCC remains unclear.This study aims to elucidate the molecular mechanism by which STAT3 regulates PD-L1 expression through the PRKDC/MYC signaling pathway,potentially inducing immune evasion in HCC,with the goal of providing potential targets for HCC immunotherapy.Methods:The expressions of STAT3 in human normal liver cells(HL-7702)and human HCC cells(HuH-7,HepG2)were detected by qRT-PCR and Western blot.Plasmids with STAT3 knockdown(si-STAT3)and PRKDC overexpression(oe-PRKDC),along with their respective negative controls(si-NC,oe-NC),were constructed and transfected into HCC cells(HuH-7)according to the experimental design,with untreated HuH-7 cells as the blank control.Western blot was used to analyze the expression of STAT3,PRKDC,PD-L1,and MYC pathway-related proteins.Cell proliferation,invasion,migration,and apoptosis of HCC cells were assessed by CCK-8,Transwell,wound healing assay,and flow cytometry.After co-culturing HuH-7 cells with human peripheral blood mononuclear cells(hPBMCs),ELISA was used to detect the secretion of the immune regulatory factor interferon γ(IFN-γ).Co-immunoprecipitation and immunofluorescence co-localization were performed to verify the interaction between STAT3 and PRKDC proteins.Results:Results of qRT-PCR and Western blot showed that the mRNA and protein levels of STAT3 were significantly elevated in HCC cells(both P＜0.05).Functional experiments demonstrated that in the si-STAT3 group,HCC cell proliferation,migration,and invasion were significantly weakened,and cell apoptosis was notably increased;the expression of PD-L1 and MYC pathway-related proteins was significantly downregulated;the secretion of IFN-γ was significantly increased after co-culturing with hPBMCs(all P＜0.05).After co-culturing with oe-PRKDC plasmids,the effects of STAT3 knockdown on HCC cells were significantly reversed(all P＜0.05).Scansite 4.0 database analysis revealed that STAT3 and PRKDC have binding sites,and co-immunoprecipitation and immunofluorescence co-localization experiments confirmed the interaction between STAT3 and PRKDC proteins.Conclusion:STAT3 is highly expressed in HCC cells and can promote HCC cell proliferation,migration,invasion,and immune evasion through interaction with PRKDC,suppress cell apoptosis,activate the MYC pathway,and increase PD-L1 expression.The STAT3/PRKDC/MYC axis may serve as a potential target for HCC immunotherapy.

Objective:To explore the value of laparoscopic and endoscopic cooperative surgery with the patient lying on supine position under general anesthesia in the operation of type I Mirizzi syndrome with choledocholithiasis.Methods:From Jan 2018 to Jan 2020, 53 cases of Mirizzi syndrome with choledocholithiasis undergoing laparoscopic and endoscopic cooperative surgery (preLC+ ERCP+ EST) at the Second Affiliated Hospital of Kunming Medical University were retrospectively analyzed.Results:53 patients successfully underwent LC without conversion to open surgery, and 2 patients failed in ERCP + EST attempt, with a success rate of 96.2%. One patient developed pancreas pseudocyst as a result of post-operative hemorrhagic necrotizing pancreatitis. Two patients suffered from chronic pancreatitis. Three patients complaining postoperative upper abdominal discomfort were finally diagnosed as stump cystic duct inflammation by MRCP, and no abnormalities were found in the follow-up of the remaining cases.Conclusion:Laparoscopic and endoscopic cooperative surgery in the treatment of patients with type I Mirizzi syndrome combined with choledocholithiasis is minimally invasive and effective.

Objective To explore the effect and mechanism of fragile site WWOX gene on regulating proliferation of gallbladder cancer cells in vitro. Methods The pcDNA3.0 - WWOX recombinant plasmid which was previous successfully built was transfected to GBC-SD cells and empty carrier by liposome medium. Liposome and GBC-SD were served as the negative control and the blank control,respectively. After 48 hours transfection, inverted microscope was used to observe the changes of gallbladder cancer cells' morphology,MTT and BrdU were used to detect the proliferation level of gallbladder cancer cells,and flow cytometry instrument was used to detect the change of the cell proliferation cycle. Results The results of inverted microscope shown: the number of GBC-SD cells in pcDNA3.0-WWOX group decreased significantly,the suspension cells and cell debris increased,while cells in the vector control,NC and Mock groups were in normal proliferation state. MTT test showed the proliferation levels of GBC-SD cells in pcDNA3.0-WWOX group was lower than those in the control group in 24 h,48 h,72 h,96 h and 120 h,and the differences were statistically significant(P < 0.05). The cell proliferation activity in the pcDNA3.0-WWOX group was obviously inhibited over time. BrdU detection results showed the cell proliferation rate of pcDNA3.0 - WWOX group was(0.44±0.03),while that in the three control groups was(0.78±0.02), (0.81±0.01)and(0.85±0.01),respectively. It showed that cell proliferation activity in pcDNA3.0-WWOX group was lower than the control groups,and the difference was statistically significant(P < 0.05). Cell cycle detection showed the cells increased in G0/G1 phase and decreased in G2/M and S phases of pcDNA3.0-WWOX group. The cell apoptosis rate was significantly higher and the proliferation index was significantly lower than those of the control groups(P < 0.05). However,there were no significant differences among the three control groups(P > 0.05). Conclusion The overexpression of WWOX gene in vitro could effectively inhibit the proliferation activity of gallbladder cancer cells. WWOX might participate in the development of the malignant biological behavior of gallbladder cancer cells. It is expected to become a new potential target for the gene therapy to gallbladder cancer.

Objective To study the behavioral changes of the spinal cord injury model to provide important data for neuroal factor therapy of the impaired spinal cord.Methods In SD rat,aged 8 weeks,(T7~T8 spinous processes as control),after the spinous process and corresponding lamina of vertebra were removed,the spinal cord was cut by using scissors to prepare the complete transversal abruptly spinal model.The behavioral score of the rat was recorded at different time.The evaluation was made in imageology and pathology.Results The score of SD rat in the experiment group was higher than the control group at different control time.The pathobiology and imageology alterations were very apparent in the damaged spinal area.Conclusion GAP-43 has neuroprotective effect on the recovery of spinal cord injury.