Nucleoside diphosphate-linked moiety X-type motif 15 R139C genotypes impact 6-thioguanine nucleotide cut-off levels to predict thiopurine-induced leukopenia in Crohn’s disease patients

BACKGROUND Thiopurine-induced leukopenia(TIL)is a life-threatening toxicity and occurs with a high frequency in the Asian population.Although nucleoside diphosphate-linked moiety X-type motif 15(NUDT15)variants significantly improve the predictive sensitivity of TIL,more than 50%of cases of this toxicity cannot be predicted by this mutation.The potential use of the 6-thioguanine nucleotide(6TGN)level to predict TIL has been explored,but no decisive conclusion has been reached.Can we increase the predictive sensitivity based on 6TGN by subgrouping patients according to their NUDT15 R139C genotypes?AIM To determine the 6TGN cut-off levels after dividing patients into subgroups according to their NUDT15 R139C genotypes.METHODS Patients’clinical and epidemiological characteristics were collected from medical records from July 2014 to February 2017.NUDT15 R139C,thiopurine S methyltransferase,and 6TGN concentrations were measured.RESULTS A total of 411 Crohn’s disease patients were included.TIL was observed in 72 individuals with a median 6TGN level of 323.4 pmol/8×10^8 red blood cells(RBC),which was not different from that of patients without TIL(P=0.071).Then,we compared the 6TGN levels based on NUDT15 R139C.For CC(n=342)and CT(n=65)genotypes,the median 6TGN level in patients with TIL was significantly higher than that in patients without(474.8 vs 306.0 pmol/8×10^8 RBC,P=9.4×10-^5;291.7 vs 217.6 pmol/8×10^8 RBC,P=0.039,respectively).The four TT carriers developed TIL,with a median 6TGN concentration of 135.8 pmol/8×10^8 RBC.The 6TGN cut-off levels were 411.5 and 319.2 pmol/8×108 RBC for the CC and CT groups,respectively.CONCLUSION The predictive sensitivity of TIL based on 6TGN is dramatically increased after subgrouping according to NUDT15 R139C genotypes.Applying 6TGN cut-off levels to adjust thiopurine therapies based on NUDT15 is strongly recommended.

Effects of flavonoids derived from Taxus yunnanensis on p-glycoprotein and cytochrome P450 3A4

The intestinal uptake of paclitaxel is hampered by trans-membrane efflux transporters such as P-glycoprotein(P-gp),and paclitaxel is mainly metabolized by cytochrome P4503A4(CYP3A4)presented in the liver.Our previous results demonstrated that flavonoids extracted from Taxus yunnanensis could improve the oral absorption of paclitaxel.The current study was purposed to investigate the effects of the flavonoid extracts on P-gp and CYP3A4 in vitro.The expression and activity of P-gp were detected by western blotting and intracellular rhodamine 123 accumulation assay in Caco-2 cells treated with the flavonoids extract.The expression of CYP3A4 was investigated by western blotting in mouse primary hepatocytes and the activity of CYP3A4 was detected by LC-MS/MS method using rat liver microsomes.Our results showed that the flavonoid extracts from T.yunnanensis could inhibit P-gp activity and concurrently decrease the expression and activity of CYP3A4.In conclusion,activity of P-gp and CYP3A4 could be inhibited by flavonoids extracted from T.yunnanensis which might be potential candidates for development of oral formulation of paclitaxel.

Comparison and development of machine learning for thalidomideinduced peripheral neuropathy prediction of refractory Crohn’s disease in Chinese population

BACKGROUND Thalidomide is an effective treatment for refractory Crohn’s disease(CD).However,thalidomide-induced peripheral neuropathy(TiPN),which has a large individual variation,is a major cause of treatment failure.TiPN is rarely predictable and recognized,especially in CD.It is necessary to develop a risk model to predict TiPN occurrence.AIM To develop and compare a predictive model of TiPN using machine learning based on comprehensive clinical and genetic variables.METHODS A retrospective cohort of 164 CD patients from January 2016 to June 2022 was used to establish the model.The National Cancer Institute Common Toxicity Criteria Sensory Scale(version 4.0)was used to assess TiPN.With 18 clinical features and 150 genetic variables,five predictive models were established and evaluated by the confusion matrix receiver operating characteristic curve(AUROC),area under the precision-recall curve(AUPRC),specificity,sensitivity(recall rate),precision,accuracy,and F1 score.RESULTS The top-ranking five risk variables associated with TiPN were interleukin-12 rs1353248[P=0.0004,odds ratio(OR):8.983,95%confidence interval(CI):2.497-30.90],dose(mg/d,P=0.002),brainderived neurotrophic factor(BDNF)rs2030324(P=0.001,OR:3.164,95%CI:1.561-6.434),BDNF rs6265(P=0.001,OR:3.150,95%CI:1.546-6.073)and BDNF rs11030104(P=0.001,OR:3.091,95%CI:1.525-5.960).In the training set,gradient boosting decision tree(GBDT),extremely random trees(ET),random forest,logistic regression and extreme gradient boosting(XGBoost)obtained AUROC values>0.90 and AUPRC>0.87.Among these models,XGBoost and GBDT obtained the first two highest AUROC(0.90 and 1),AUPRC(0.98 and 1),accuracy(0.96 and 0.98),precision(0.90 and 0.95),F1 score(0.95 and 0.98),specificity(0.94 and 0.97),and sensitivity(1).In the validation set,XGBoost algorithm exhibited the best predictive performance with the highest specificity(0.857),accuracy(0.818),AUPRC(0.86)and AUROC(0.89).ET and GBDT obtained the highest sensitivity(1)and F1 score(0.8).Overall,compared with other state-of-the-art classifiers such as ET,GBDT and RF,XGBoost algorithm not only showed a more stable performance,but also yielded higher ROC-AUC and PRC-AUC scores,demonstrating its high accuracy in prediction of TiPN occurrence.CONCLUSION The powerful XGBoost algorithm accurately predicts TiPN using 18 clinical features and 14 genetic variables.With the ability to identify high-risk patients using single nucleotide polymorphisms,it offers a feasible option for improving thalidomide efficacy in CD patients.

Anti-Inflammatory Mechanism of Total Glycosides of Acanthopanax Giraldii

Objective:To study the anti-inflammatory mechanisms of total glycosides of Acanthopanax Giraldii (TGA).Methods:The changes of prostaglandin E_2(PGE_2),tumor necrosis factor(TNF-α),nitric oxide(NO), and expressions of COX-1 mRNA and COX-2 mRNA in BALB/c mouse macrophages were observed by the radioimmunoassay,ELISA and nitric acid reduction and RT-PCR in the presence or absence of TGA.Results: (1) TGA could significantly decrease the production of PGE_2 and NO in mouse peritoneal macrophages.The inhibitory ra...

Association of polymorphisms in C1orf106,IL1RN,and IL10 with post-induction infliximab trough level in Crohn’s disease patients

Background:Trough levels of the post-induction serum infliximab(IFX)are associated with short-term and long-term responses of Crohn’s disease patients to IFX,but the inter-individual differences are large.We aimed to elucidate whether single gene polymorphisms(SNPs)within FCGR3A,ATG16L1,C1orf106,OSM,OSMR,NF-jB1,IL1RN,and IL10 partially account for these differences and employed a multivariate regression model to predict patients’post-induction IFX levels.Methods:The retrospective study included 189 Crohn’s disease patients undergoing IFX therapy.Post-induction IFX levels were measured and 41 tag SNPs within eight genes were genotyped.Associations between SNPs and IFX levels were analysed.Then,a multivariate logistic-regression model was developed to predict whether the patients’IFX levels achieved the threshold of therapy(3 lg/mL).Results:Six SNPs(rs7587051,rs143063741,rs442905,rs59457695,rs3213448,and rs3021094)were significantly associated with the post-induction IFX trough level(P=0.015,P<0.001,P=0.046,P=0.022,P=0.011,P=0.013,respectively).A multivariate prediction model of the IFX level was established by baseline albumin(P=0.002),rs442905(P=0.025),rs59457695(P=0.049),rs3213448(P=0.056),and rs3021094(P=0.047).The area under the receiver operating characteristic curve(AUROC)of this prediction model in a representative training dataset was 0.758.This result was verified in a representative testing dataset,with an AUROC of 0.733.Conclusions:Polymorphisms in C1orf106,IL1RN,and IL10 play an important role in the variability of IFX post-induction levels,as indicated in this multivariate prediction model of IFX levels with fair performance.

Multi-alleles predict primary non-response to infliximab therapy in Crohn’s disease

Background:Infliximab(IFX)is the first-line treatment for patients with Crohn’s disease(CD)and is noted for its relatively high cost.The therapeutic efficacy of IFX has noticeable individual differences.Known single-gene polymorphisms(SNPs)are inadequate for predicting non-response to IFX.In this study,we aimed to identify new genetic factors associated with IFX-therapy failure and to predict non-response to IFX by developing a multivariate predictive model.Methods:In this retrospective study,we collected and analysed the data of Chinese patients with CD who received IFX therapy at one hospital between June 2013 and June 2019.Primary non-response(PNR)and non-durable response(NDR)were evaluated using a simple endoscopic score for CD(SES-CD).A total of 125 SNPs within 44 genes were genotyped.A multivariate logistic-regression model was established to predict non-response to IFX.An area-under-the-receiver-operatingcharacteristics curve(AUROC)was applied to evaluate the predictive model performance.Results:Forty-two of 206(20.4%)patients experienced PNR and 15 of 159(9.4%)patients experienced NDR.Nine SNPs were associated with PNR(P<0.05).A PNR predictive model was established,incorporating 2-week high-sensitivity C-reactive protein(hs-CRP),rs61886887,rs61740234,rs357291,rs2269330,and rs111504845,and the AUROC on training and testing data sets were 0.818(P<0.001)and 0.888(P<0.001),respectively.At week 14,hs-CRP levels≥2.25 mg/L were significantly associated with NDR(AUROC=0.815,P<0.001).PNR-associated SNPs were not mutually associated with NDR,suggesting distinct mechanisms between PNR and NDR.Conclusion:Genetic polymorphisms are significantly associated with response to IFX among Chinese CD patients.