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Purpose@#Pancreatic cancer (PC) is a common malignant tumor of the digestive system, and its 5-year survival rate is only 4%. N6-methyladenosine (m6A) RNA methylation is the most common post-transcriptional modification and dynamically regulates cancer development, while its role in PC treatment remains unclear. @*Materials and Methods@#We treated PC cells with gemcitabine and quantified the overall m6A level with m6A methylation quantification. Real-time quantitative reverse transcription polymerase chain reaction and Western blot analyses were used to detect expression changes of m6A regulators. We verified the m6A modification on the target genes through m6A-immunoprecipitation (IP), and further in vivo experiments and immunofluorescence (IF) assays were applied to verify regulation of gemcitabine on Wilms’ tumor 1–associated protein (WTAP) and MYC. @*Results@#Gemcitabine inhibited the proliferation and migration of PC cells and reduced the overall level of m6A modification. Additionally, the expression of the “writer” WTAP was significantly downregulated after gemcitabine treatment. We knocked down WTAP in cells and found target gene MYC expression was significantly downregulated, m6A-IP also confirmed the m6A modification on MYC. Our experiments showed that m6A-MYC may be recognized by the “reader” IGF2BP1. In vivo experiments revealed gemcitabine inhibited the tumorigenic ability of PC cells. IF analysis also showed that gemcitabine inhibited the expression of WTAP and MYC, which displayed a significant trend of co-expression. @*Conclusion@#Our study confirmed that gemcitabine interferes with WTAP protein expression in PC, reduces m6A modification on MYC and RNA stability, thereby inhibiting the downstream pathway of MYC, and inhibits the progression of PC.
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AIM:To explore the effect of tomatidine(TA)on lipopolysaccharide(LPS)-induced nerve cell in-jury and the underlying mechanism.METHODS:The neuroinflammation model was induced by treating SH-SY5Y cells with LPS.These cells were divided into control(CON),LPS,and LPS+TA groups.The LPS group was treated with 5 μg/mL LPS for 24 h to establish an inflammatory model.The LPS+TA group was first treated with 5 μmol/L tomatidine for 24 h and then co-cultured with 5 μg/mL LPS for 24 h.Cell viability was detected using the CCK-8 assay.RT-qPCR was used to detect the mRNA expression of inflammatory factors tumor necrosis factor-α(TNF-α)and interleukin-1β(IL-1β).The protein expression of transcription factor EB(TFEB),p-TFEB,P62,and microtubule-associated protein 1 light chain 3(LC3)expression was detected through Western blot.TFEB localization and cleaved caspase-3 expression were detected through immunofluorescence.The cell apoptosis rate was detected through flow cytometry.RESULTS:(1)Compared with the CON group,the LPS group exhibited significant increases in IL-1β and TNF-α mRNA levels(P＜0.05),the cell apoptosis rate,and the p-TFEB level(P＜0.01).By contrast,P62,LC3-Ⅱ/LC3-Ⅰ,and TFEB protein ex-pression levels decreased significantly(P＜0.05),and TFEB was mainly localized in the cytoplasm.(2)Compared with the LPS group,tomatidine treatment significantly decreased the p-TFEB protein expression level(P＜0.01),increased the TFEB protein expression level(P＜0.01),and promoted the TFEB protein to migrate into the nucleus.After treatment of tomatidine,the LC3-Ⅱ/LC3-Ⅰ protein expression level significantly increased(P＜0.05),and the cell apoptosis rate signifi-cantly decreased(P＜0.01).In addition,the TNF-α mRNA level significantly decreased after tomatidine treatment(P＜0.01).CONCLUSION:Tomatidine improves autophagy dysfunction,inflammatory reaction,and cell apoptosis induced by LPS via activating the transcription factor EB.
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Objective:To study factors associated with postoperative acute pancreatitis (POAP) in patients following pancreaticoduodenectomy.Methods:This retrospective analysis included 60 patients who underwent pancreaticoduodenectomy at the First Affiliated Hospital of Soochow University from Jan 2020 to Aug 2021. Enhanced computed tomography was used to identify POAP during postoperative period of 4 to 9 days. Univariate analysis and multivariate analysis were used to find out the risk factors of POAP.Results:Of the 60 patients, 13 cases (21.7%) developed POAP. The incidence of clinically related pancreatic fistula with abdominal abscess (76.9% vs.19.1%, χ2=15.71, P<0.000 1), postoperative hospital stay (26 d vs. 18 d, U=141.5, P=0.002 5) and the severity of complications (Clavien-Dindo grade≥Ⅲ: 53.8% vs. 21.3%, χ2=5.32, P=0.02) were significantly higher in the POAP group. But there was no significant deviation between the two groups when it comes to the severe post pancreatectomy delayed hemorrhage (7.7% vs. 0, χ2=3.68, P=0.06) and the delayed gastric emptying (30.8% vs. 21.3%, χ2=0.51, P=0.47). In the univariate analysis, patients with higher body mass index ( P=0.000 3), smaller main pancreatic duct diameter ( P<0.000 1) and softer texture of the pancreas ( P=0.009) were more likely to develop POAP after pancreaticoduodenectomy. In the multivariate analysis, the pancreatic duct diameter≤2 mm ( OR=0.005,95% CI 0.000 06-0.44, P=0.020), the softer texture of pancreas ( OR=0.005, 95% CI 0.000 04-0.47, P=0.023) were risk factors for POAP. Conclusions:Patients with postoperative acute pancreatitis increased the incidence of pancreatic fistula complicating abdominal abscess.Small caliber pancreatic tube, soft texture of pancreas were risk factors of POAP.
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Objective To investigate the distribution and proportion of CD8α+α + T cells in lesions and peripheral blood of patients with psoriasis,and to assess their roles in the pathogenesis of psoriasis.Methods An immunofluorescence assay was performed to observe the distribution of CD8α+α+ T cells in lesions of 5 patients with progressive psoriasis vulgaris and normal skin of 5 healthy human controls.Flow cytometry was conducted to determine the proportion of CD8α+α+ T cells,and to measure the expressions of interferon (IFN)-γ and tumor necrosis factor (TNF)-α in peripheral blood from 10 patients with progressive psoriasis vulgaris and 8 healthy human controls.Statistical analysis was carried out by t test with GraphPad Prism software.Results A massive infiltrate mainly composed of CD8α+α+ T cells but not CD8α+β+ T cells was observed in the upper dermis of lesions from the 5 patients with psoriasis,while there was no infiltrate of CD8α+β+ or CD8α+α+ T cells in the normal skin of 5 healthy human controls.Flow cytometry revealed that the proportion of CD8α+α+ T cells was significantly higher in peripheral blood from 10 patients with psoriasis than in that from 8 healthy human controls (26.47％ ± 12.99％ vs.9.12％ ± 4.80％,t =3.96,P＜ 0.001).Significant differences were also noted between the psoriatic patients and healthy human controls in the percentage of cells secreting IFN-γ (47.36％ ± 19.38％ vs.13.44％ ± 9.21％,t =4.54,P ＜ 0.001) and cells secreting TNF-α (54.14％ ± 21.14％ vs.34.03％ ± 17.22％,t =2.17,P ＜ 0.05) in peripheral blood CD8α+α+ T cells.Conclusions Both the distribution and proportion of CD8α+α+ T cells are increased in lesions and peripheral blood from patients with psoriasis,suggesting that CD8α+α+ T cells may be the main subgroup of CD8+ T cells that contribute to the pathogenesis of psoriasis.