Multiparametric MRI Combined with Apparent Diffusion Coefficient Histogram Analysis for Assessing Variant Histology in Urothelial Carcinoma / 中山大学学报(医学科学版)

ObjectiveTo investigate the feasibility of multiparametric MRI （mpMRI） combined with histogram analysis of apparent diffusion coefficient （ADC） in the assessment of patients with variant histology （VH） of urothelial carcinoma （UC）. MethodWe retrospectively analyzed the data of patients pathologically diagnosed with UC who underwent mpMRI in the First Affiliated Hospital of Sun Yat-sen University between March 2015 and March 2023. The patients were divided into VH group （urothelial carcinoma mixed with other histologies） and non-VH group （pure urothelial carcinoma） according to pathological results. We performed propensity score 1：1 nearest-neighbor matching on the two groups based on age and gender and 49 patients were included in each group. The regions of interest （ROIs） of the whole tumor were delineated manually by using ITK-SNAP software and Pyradiomics was applied to extract ADC histogram parameters. We compared the clinicopathological data， MRI morphological features and ADC histogram parameters between the groups. Multivariate logistic regression was used to identify independent risk factors and construct the prediction model. Receiver operating characteristic （ROC） curve analyses were performed to evaluate the diagnostic performance of these parameters for determining VH of UC. ResultsMRI morphological features including the lesion shape， vesical imaging-reporting and data system （Ⅵ-RADS）score， enhancement pattern and suspicious lymph node metastasis were markedly different between the two groups （all P < 0.05）. ADC mean， ADC median， ADC25th， ADC75th， ADC10th and ADC90th were significantly lower in patients with VH than those in non-VH group （all P<0.05）. Multivariate logistic regression analysis showed enhancement pattern， ADC25th， ADC75th and ADC mean were independent predictors （P < 0.05）. The combined model yielded the best predictive performance， with an area under the ROC curve （AUC） of 0.91 （95% CI： 0.83-0.96）. ConclusionsMpMRI combined with whole-tumor histogram analysis of ADC can serve as a reliable method for evaluating the presence of VH in UC， further to assist the clinical decision making.

Effect of metformin on apoptosis of renal cell carcinoma cells in vitro and its mechanisms / 南方医科大学学报

<p><b>OBJECTIVE</b>To evaluate the effect of metformin on the apoptosis of renal cell carcinoma (RCC) cells in vitro and its mechanisms.</p><p><b>METHODS</b>Fluorescent microscopy and flow cytometry were used to examine the changes in the apoptosis of 786-O cells after metformin treatment. The possible signaling molecules involved in this process were analyzed by immunoblot analysis of AMP-activated protein kinase (AMPK) signaling and caspase 9.</p><p><b>RESULTS</b>Metformin induced apoptosis and caspase 9 activation in 786-O cells in low-serum medium but not in normal-serum medium. Metformin also induced AMPK activation in 786-O cells, but this activation was not associated with the cell proliferation inhibition or apoptosis-inducing effect of metformin.</p><p><b>CONCLUSION</b>Metformin can induce apoptosis of RCC cells in vitro, suggesting its potential as a therapeutic agent for RCC.</p>

Expression and antibody preparation of FKBP38 and its application / 南方医科大学学报

<p><b>OBJECTIVE</b>To obtain recombinant N-and C-terminal of FKBP38 and prepare anti-FKBP38 polyclonal antibody for Western blotting (WB), immunohistochemical (IHC) and immunofluorescence (IF) analyses.</p><p><b>METHODS</b>The N-terminal (1-207 aa) and C-terminal (209-387 aa) cDNA of FKBP38 were sub-cloned from the full-length cDNA of FKBP38 and ligated to prokaryotic expression plasmid pGEX-6P-1 for construction of the recombinant vectors pGEX-6P-1-FKBP38-N and pGEX-6P-1-FKBP38-C. After sequencing, the recombinant vectors were transformed into E.coli BL21 and GST-tagged FKBP38-NT and FKBP38-CT were induced by IPTG. The proteins were purified by Glutathione affinity chromatography column and characterized by SDS-PAGE. Rabbits were immunized with the purified recombinant protein to prepare the antiserum, which were analyzed by WB, IHC and IF.</p><p><b>RESULTS</b>The recombinant vectors pGEX-6P-1-FKBP38-N and pGEX-6P-1-FKBP38-C were successfully constructed. After IPTG induction, the E.coli transformed with these plasmids expressed GST-tagged protein, which was successfully purified. Western blotting demonstrated that the purified antibody could specifically bind to FKBP38 in various cell lines. Immunofluorescence assay showed that FKBP38 was located mainly on the mitochondria. Immunohistochemical analysis revealed cytoplasmic location of FKBP38 in breast cells.</p><p><b>CONCLUSION</b>We successfully expressed and purified N- and C-terminal of FKBP38, and FKBP38 polyclonal antibody we prepared can specifically recognize FKBP38 in SB, IF and IHC assays, which facilitates further functional investigation of FKBP38.</p>