Background/Aims: Biliary tract cancer (BTC) frequently harbors KRAS mutations, which are associated with resistance to traditional treatment and a poor prognosis. Synthetic lethality (SL) strategy may provide other targets of KRAS. Therefore, we aim to identify and validate potential therapeutic targets of KRAS for the treatment of BTC via SL. Methods: The dependency (DepMap) projects were used to predict the synthetic lethal gene of KRAS. FDA-approved anticancer drug library was applied to screen potential drugs effective against KRAS-mutant BTC. Furthermore, the synthetic lethal effects or corresponding mechanisms of potential genes and drugs on BTC were investigated using KRAS-mutant and KRAS-wild type BTC cell lines, patient-derived xenografts (PDX), and KRAS oncogene-driven tumor models, as well as other KRAS-mutant cancer cell lines. Results: Initially, we discovered that the loss of GATA2 reduced the viability of KRAS-mutant but not KRAS-wild-type BTC. Subsequently, the drug library screened out disulfiram, which primarily exerts a synthetic lethal effect by inhibiting interleukin-1β (IL-1β) in KRAS-mutant BTC. Mechanistically, GATA2 specifically enhanced the transcription of IL-1β to promote NF-κB signaling in KRAS-mutant BTC. IL-1β inhibition phenocopied GATA2 deficiency, leading to reduced KRAS-mutant BTC viability. These synthetically lethal effects were confirmed using PDX, a KRAS oncogene-driven tumor model, as well as in other KRAS-mutant cancer cell lines. Conclusions In summary, these results indicate that inhibiting GATA2/IL1β could be a therapeutic strategy in KRAS-mutant BTC and potentially other cancers.

The sensitivity of cardiac troponin testing for diagnosing acute myocardial infarction(AMI)varies over time from chest pain onset.This study aimed to determine the diagnostic performance of point-of-care testing cardiac troponin T(POCT-cTnT)at different time intervals post-symptom onset to refine rapid rule-out approaches for AMI.Methods This retrospective study included 6,024 patients presenting with chest pain from January 2018 to December 2022.POCT-cTnT and central lab cTnI levels were measured on admission.Receiver operating charac-teristics analysis stratified by time windows assessed the accuracy of POCT-cTnT for diagnosing AMI.Results The overall AUC of POCT-cTnT for diagnosing AMI was 0.826(95%CI:0.816～0.836),with a sensitivity of 72.81%and a specificity of 86.26%.According to the time intervals of chest pain onset(＜3 hours,3～6 hours,6～12 hours,12～24 hours,24～72 hours,and≥72 hours),the AUC values for groups after 6～12 hours were 0.918,0.928,0.920 and 0.908,respectively,with no statistically significant difference(P＞0.05),but all were higher than the groups within 6 hours(P＜0.001).According to the time of chest pain onset,the AUC for the≥8h group was 0.921,with a negative predictive value(NPV)of 98.1%and a negative likelihood ratio(-LR)of 0.11.Its AUC was higher than those of the≥3 h,≥2 h,≥1 h,and overall groups(P＜0.05),but there was no statistically significant differ-ence compared with the groups after≥4 h(P＞0.05).Conclusions Chest pain onset time has a certain impact on the performance of a single POCT-cTnT test for diagnosing AMI.The duration from chest pain onset to hospital admission combined with POCT-cTnT test may improve the reliability in diagnosing AMI.Specifically,a single POCT-cTnT test at four hours after chest pain onset,especially eight hours after chest pain onset,can diagnose or exclude AMI.

Objective The role of this essay is to explore the relationship of BIM deletion polymorphism and paclitaxel intrinsic resistance in breast cancer. Methods Human breast cancer cell lines were screened by techniques of PCR and gene sequencing to detect BIM deletion polymorphism.MTS was used to detect the cytotoxic effects of paclitaxel in different cell lines. Meanwhile,levels of BIM mRNA and protein were detected by rtPCR and Western Blot. Results Comparing with the wild type cell line(MCF7),T47D was a deletion cell line with BIM deletion polymorphism and resistant to paclitaxel(T47D vs.MCF-7,IC50>30le vs.IC50=0.16 vs.02 μmol/L). Moreover,the ratio of BIM EXON3 to EXON4 was significantly increased and the level of functional BIM protein was down-regulated in T47D compared with MCF7(P < 0.05). Conclusion BIM deletion polymorphism might initiate intrinsic resistance to paclitaxel therapy in breast cancer.

Our previous report has demonstrated that 5-formylhonokiol (FH), a derivative of honokiol (HK), exerts more potent anti-proliferative activities than honokiol in several tumor cell lines. In present study, we first explored the antiangiogenic activities of 5-formylhonokiol on proliferation, migration and tube formation of human umbilical vein endothelial cells (HUVECs) for the first time in vitro. Then we investigated the in vivo antiangiogenic effect of 5-formylhonokiol on zebrafish angiogenesis model. In order to clarify the underlying molecular mechanism of 5-formylhonokiol, we investigated the signaling pathway involved in controlling the angiogenesis process by western blotting assay. Wound-healing results showed that 5-formylhonokiol significantly and dose-dependently inhibited migration of cultured human umbilical vein enthothelial cells. The invasiveness of HUVEC cells was also effectively suppressed at a low concentration of 5-formylhonokiol in the transwell assay. Further F-actin imaging revealed that inhibitory effect of 5-formylhonokiol on invasion may partly contribute to the disruption of assembling stress fiber. Tube formation assay, which is associated with endothelial cells migration, further confirmed the anti-angiogenesis effect of 5-formylhonokiol. In in vivo zebrafish angiogenesis model, we found that 5-formylhonokiol dose-dependently inhibited angiogenesis. Furthermore, western blotting showed that 5-formylhonokiol significantly down-regulated extracellular signal-regulated kinase (ERK) expression and inhibited the phosphorylation of ERK but not affecting the total protein kinase B (Akt) expression and related phosphorylation, suggesting that 5-formylhonokiol might exert anti-angiogenesis capacity via down-regulation of the ERK signal pathway. Taken together, these data suggested that 5-formylhonokiol might be a viable drug candidate in antiangiogenesis and anticancer therapies.
Actins/metabolism ; Angiogenesis Inhibitors/*pharmacology ; Animals ; Antineoplastic Agents, Phytogenic/pharmacology ; Biphenyl Compounds/*pharmacology ; Blotting, Western ; Cell Line, Tumor ; Cell Movement/drug effects ; Cell Proliferation/drug effects ; Cells, Cultured ; Dose-Response Relationship, Drug ; Drugs, Chinese Herbal ; Embryo, Nonmammalian/drug effects/metabolism ; Endothelium, Vascular/*drug effects/metabolism ; Extracellular Signal-Regulated MAP Kinases/*antagonists & inhibitors/metabolism ; Humans ; Lignans/*pharmacology ; Neovascularization, Physiologic/*drug effects ; Signal Transduction/*drug effects ; Umbilical Veins/cytology ; Wound Healing ; Zebrafish/embryology/metabolism