Objective:To investigate the molecular mechanism of the 5-methylcytosine(m5C)reader Y-box binding protein 1(YBX1)in participating in the development and progression of colorectal cancer(CRC)by regulating the stability of the ferroptosis inhibitor membrane-spanning 4-domains subfamily A 15(MS4A15).Methods:Bioinformatics databases were used to investigate the mRNA and protein expression levels of YBX1 in CRC.RT-qPCR was used to measure the expression level of YBX1 in CRC cells.LC-MS was used to measure the level of m5C modification in CRC cells and nor-mal colorectal mucosal cells.CCK-8 assay was used to observe the effect of YBX1 on the proliferation of CRC cells,Transwell assay was used to observe its effect on the migration ability of CRC cells,and flow cytometry was sued to observe its effect on the apoptosis of CRC cells.Bioinformatics methods were used to identify the ferrop-tosis inhibitors that can interact with YBX1 and potential m5C modification sites.GEPIA2 was used to analyze the association between the expression of YBX1 and MS4A15.The expression of YBX1 was inhibited,and then the mRNA expression level and m5C modifica-tion level of MS4A15 were analyzed.The catRAPID database was used to find the binding sites between YBX1 protein and MS4A15 mRNA.CRC cells were treated with actinomycin D after inhibition of YBX1 expression,and RT-qPCR was used to measure the stabil-ity of MS4A15 mRNA.The expression of MS4A15 was inhibited,and then the proliferative activity,migration ability,and apoptosis rate of cells were measured,as well as the expression levels of the key indicators for ferroptosis,including MDA,ROS,and Fe2+.Results:High mRNA and protein expression levels of YBX1 were observed in CRC,and YBX1 was highly expressed in CRC cells.The m5C modification level of CRC cells was significantly higher than that of normal colorectal mucosal cells.YBX1 could promote the prolifera-tion and migration of CRC cells and inhibit the apoptosis of CRC cells.The bioinformatics analysis showed that YBX1 was positively correlated with the expression level of the ferroptosis inhibitor MS4A15,and there were multiple m5C modification sites on MS4A15.Inhibition of YBX1 expression could reduce the mRNA expression level and m5C modification level of MS4A15 and the stability of MS4A15 mRNA.There were significant reductions in the proliferative activity and migration ability of CRC cells and a significant in-crease in the apoptosis rate of CRC cells after inhibition of MS4A15 expression,with significant increases in the content of MDA,ROS,and Fe2+.Conclusion:These results show that YBX1 promotes the development and progression of CRC by stabilizing MS4A15 via m5C modification,which provides a promising targeted therapeutic strategy for CRC patients.

BACKGROUND: Breast cancer patients who are positive for hormone receptor typically exhibit a favorable prognosis. It is controversial whether chemotherapy is necessary for them after surgery. Our study aimed to establish a multigene model to predict the relapse of hormone receptor-positive early-stage Chinese breast cancer after surgery and direct individualized application of chemotherapy in breast cancer patients after surgery. METHODS: In this study, differentially expressed genes (DEGs) were identified between relapse and nonrelapse breast cancer groups based on RNA sequencing. Gene set enrichment analysis (GSEA) was performed to identify potential relapse-relevant pathways. CIBERSORT and Microenvironment Cell Populations-counter algorithms were used to analyze immune infiltration. The least absolute shrinkage and selection operator (LASSO) regression, log-rank tests, and multiple Cox regression were performed to identify prognostic signatures. A predictive model was developed and validated based on Kaplan-Meier analysis, receiver operating characteristic curve (ROC). RESULTS: A total of 234 out of 487 patients were enrolled in this study, and 1588 DEGs were identified between the relapse and nonrelapse groups. GSEA results showed that immune-related pathways were enriched in the nonrelapse group, whereas cell cycle- and metabolism-relevant pathways were enriched in the relapse group. A predictive model was developed using three genes ( CKMT1B , SMR3B , and OR11M1P ) generated from the LASSO regression. The model stratified breast cancer patients into high- and low-risk subgroups with significantly different prognostic statuses, and our model was independent of other clinical factors. Time-dependent ROC showed high predictive performance of the model. CONCLUSIONS A multigene model was established from RNA-sequencing data to direct risk classification and predict relapse of hormone receptor-positive breast cancer in Chinese patients. Utilization of the model could provide individualized evaluation of chemotherapy after surgery for breast cancer patients.
Humans ; Female ; Breast Neoplasms/genetics* ; East Asian People ; Neoplasm Recurrence, Local/genetics* ; Breast ; Algorithms ; Chronic Disease ; Prognosis ; Tumor Microenvironment

Imipenem is a carbapenem antibiotic. However, Imipenem could not be marketed owing to its instability and nephrotoxicity until cilastatin, an inhibitor of renal dehydropeptidase-I (DHP-I), was developed. In present study, the potential roles of renal organic anion transporters (OATs) in alleviating the nephrotoxicity of imipenem by cilastatin were investigated and in rabbits. Our results indicated that imipenem and cilastatin were substrates of hOAT1 and hOAT3. Cilastatin inhibited hOAT1/3-mediated transport of imipenem with IC values comparable to the clinical concentration, suggesting the potential to cause a clinical drug-drug interaction (DDI). Moreover, imipenem exhibited hOAT1/3-dependent cytotoxicity, which was alleviated by cilastatin and probenecid. Furthermore, cilastatin and probenecid ameliorated imipenem-induced rabbit acute kidney injury, and reduced the renal secretion of imipenem. Cilastatin and probenecid inhibited intracellular accumulation of imipenem and sequentially decreased the nephrocyte toxicity in rabbit primary proximal tubule cells. Renal OATs, besides DHP-I, was also the target of interaction between imipenem and cilastatin, and contributed to the nephrotoxicity of imipenem. This therefore gives in part the explanation about the mechanism by which cilastatin protected against imipenem-induced nephrotoxicity. Thus, OATs can potentially be used as a therapeutic target to avoid the renal adverse reaction of imipenem in clinic.

Objective To evaluate the value of procalcitonin (PCT) combined with CURB-65 score in the elderly patients with community acquired pneumonia(CAP). Methods Seventy-eight elderly patients with CAP were selected in the Emergency Department of Xuanwu Hospital Capital Medical University,After admission,blood routine, PCT, blood gas analysis and biochemical examination were given, and Acute Physiology and Chronic Health Evaluation(APACHEⅡ) and CURB-65 score were carried out. According to the prognosis,the patients were divided into death group (16 cases) and survival group (62 cases),The difference of PCT,white blood cell(WBC),CURB-65 score and APACHE Ⅱ score in the two groups were compared. The differences of area under ROC curve of APACHE II score,procalcitonin (PCT),CURB-65 score,PCT and CURB-65 score were compared. Results The PCT,CURB-65 and APACHEE Ⅱ scores of the death group and the survival group were (3. 35±1. 79) μg/L vs. (2. 05±1. 89) μg/L,(2. 06±0. 85) points vs. (1. 40±0. 99) points,(20. 50±4. 06) points vs. (14. 13+5. 63) points,respectively. There were significant differences between the two groups ( P＜0. 05) . The number of WBCs in survival group and survival group were ( 9. 90 ± 3. 04)×109/L and ( 8. 77 ± 3. 70)×109/L, respectively, with no significant difference between the two groups (P＝0. 263); the area under the ROC curve of PCT predicting death was 0. 716 (P＝0. 001),the area under the ROC curve of CURB-65 predicting death was 0. 679 ( P＝0. 005), and the area under the ROC curve of APACHE II score was 0. 836 (P＝0. 001) ,which was larger than PCT and CRUB-65 (P＜0. 05). The area under ROC curve of death predicted by PCT and CRUB-65 was 0. 775 (P＝0. 001). There was no significant difference between PCT and CRUB-65 and APACHE II (P＝0. 345) . Conclusion PCT combined with CURB-65 score can accurately and rapidly assess the condition of elderly patients with community-acquired pneumonia,and has important application value.