Influence of tumor thrombus morphology on the surgical complexity in renal cell carcinoma with inferior vena cava tumor thrombus: a single-center, large-sample study from China.

BACKGROUND: The morphology of tumor thrombus varies from person to person and it may affect surgical methods and tumor prognosis. However, studies on the morphology of tumor thrombus are limited. The purpose of our study was to evaluate the impact of tumor thrombus morphology on surgical complexity. METHODS: We retrospectively reviewed the clinical data of 229 patients with renal cell carcinoma combined with inferior vena cava (IVC) tumor thrombus who underwent surgical treatment at Peking University Third Hospital between January 2014 and December 2021. The patients were divided into floating morphology (107 patients) and filled morphology (122 patients) tumor thrombi groups. Chi-square and Mann-Whitney U tests were used for categorical and continuous variables, respectively. Postoperative complications were evaluated using the Clavien-Dindo surgical complication classification method. RESULTS: Patients with filled morphology tumor thrombus required more surgical techniques than those with floating morphology tumor thrombus, which was reflected in more open surgeries (P < 0.001), more IVC interruptions (P <0.001), lesser use of the delayed occlusion of the proximal inferior vena cava (DOPI) technique (P < 0.001), and a greater need for cut-off of the short hepatic vein (P < 0.001) and liver dissociation (P = 0.001). Filled morphology significantly increased the difficulty of surgery in patients with renal cell carcinoma with tumor thrombus, reflected in longer operation time (P < 0.001), more surgical blood loss (P <0.001), more intra-operative blood transfusion (P < 0.001), and longer postoperative hospital stay (P < 0.001). Filled morphology tumor thrombus also led to more postoperative complications (53% vs. 20%; P < 0.001). CONCLUSION: Compared with floating morphology thrombus, filled morphology thrombus significantly increased the difficulty of surgery in patients with renal cell carcinoma with IVC tumor thrombus.

Transplantation of 5-azacytidine treated cardiac fibroblasts improves cardiac function of infarct hearts in rats.

BACKGROUND: Cellular cardiomyoplasty by transplantation of various cell types has been investigated as potential treatments for the improvement of cardiac function after myocardial injury. A major barrier for the clinical application of cell transplantation is obtaining sufficiently large quantities of suitable cells. Allogeneic cellular cardiomyoplasty may provide an alternative source of abundant, transplantable, myogenic cells by in vitro manipulation of cardiac fibroblasts using chemicals including 5-azacytidine. This study evaluated cardiomyogenic differentiation of cardiac fibroblasts, their survival in myocardial scar tissue, and the effect of the implanted cells on heart function. METHODS: Primary cardiac fibroblasts from neonatal rats were treated with 5-azacytidine (10 µmol/L) or control. Treatment of 5-azacytidine caused myogenic differentiation of cultured cardiac fibroblasts, as defined by elongation and fusion into multinucleated myotubes with sarcomeric structures as identified by electron microscopy, and positive immunostaining for cardiac specific proteins, troponin I and ß-myosin heavy chain (ß-MHC) and the gap junction protein connexin 43. The myogenic cells (1.0 × 106) were transplanted into the infarcted myocardium 2 weeks after coronary artery occlusion. RESULTS: By 1 month after transplantation, the converted fibroblasts gave rise to a cluster of cardiac-like muscle cells that in the hearts occupied a large part of the scar with positive immunostaining for the myogenic proteins troponin I and ß-MHC. Engrafted cells also expressed the gap junction protein connexin 43 in a disorganized manner. There was no positive staining in the control hearts treated with injections of culture medium. Heart function was evaluated at 6 weeks after myocardial injury with echocardiographic and hemodynamic measurements. Improvement in cardiac function was seen in the hearts transplanted with the 5-azacytidine-treated cardiac fibroblasts which was absent in the hearts treated with control. CONCLUSION: The 5-azacytidine has a unique capacity to induce myogenesis in cardiac fibroblasts in vitro and transplantation of cardiac-like muscle cells into ventricular scar tissue improves myocardial function.

Identification and differentiation of magnetically labeled mesenchymal stem cells in vivo in swines with myocardial infarction.

We aim to track mesenchymal stem cells (MSCs) after magnetically labeling and test the ability of these cells differentiate into cardiomyocytes in vivo. Therefore, 20 swines were divided into four groups, sham-operated group (n=3); acute myocardial infarction (AMI) transplanted with PBS (n=3); labeled MSCs (n=7) and unlabeled MSCs (n=7) group. 10(7) labeled or unlabeled cells were intracoronary delivered after MI (4.8+/-1.3 days), and serial cardiac MR (3.0T) imaging studies were performed at 0, 4 and 8 weeks after transplantation, then the results were confirmed by histological and western blot analysis. We demonstrated that labeled MSCs can be reliably detected and tracked in vivo using MR imaging. In particular, we provided the evidence of regeneration of labeled MSCs in vivo by histological examination and western blot analysis.

Trichomislin, a novel ribosome-inactivating protein, induces apoptosis that involves mitochondria and caspase-3.

Trichomislin, a novel ribosome-inactivating protein, was cloned from the genome of Trichosanthes kirilowii Maxim. The gene was recombined to prokaryotic expression vector and the protein was purified by cation-exchange chromatography. The secondary structure of trichomislin was measured by circular-dichroism analysis and the ratios of alpha-helices and beta-sheets were calculated. Trichomislin could inhibit the synthesis of protein in rabbit reticulocyte lysate systems and its reaction mechanism was to inactivate ribosome as an rRNA N-glycosidase. Antitumor analyses indicated trichomislin induced the apoptosis and inhibited the growth of choriocarcinoma cells. Further investigation showed that trichomislin could bind to and enter choriocarcinoma cells, and then increase the caspase-3 activity in a time-dependent manner. At the same time, the concentration of cytochrome c in cytosol increased while that in mitochondria decreased. These results suggested that trichomislin induced apoptosis by releasing cytochrome c from mitochondria which then triggered the caspase family member activation.