Oncogenic and immunological roles of RACGAP1 in pan-cancer and its potential value in nasopharyngeal carcinoma.

A particular GTPase-activating protein called RACGAP1 is involved in apoptosis, proliferation, invasion, metastasis, and drug resistance in a variety of malignancies. Nevertheless, the role of RACGAP1 in pan-cancer was less studied, and its value of the expression and prognostic of nasopharyngeal carcinoma (NPC) has not been explored. Hence, the goal of this study was to investigate the oncogenic and immunological roles of RACGAP1 in various cancers and its potential value in NPC. We comprehensively analyzed RACGAP1 expression, prognostic value, function, methylation levels, relationship with immune cells, immune infiltration, and immunotherapy response in pan-cancer utilizing multiple databases. The results discovered that RACGAP1 expression was elevated in most cancers and suggested poor prognosis, which could be related to the involvement of RACGAP1 in various cancer-related pathways such as the cell cycle and correlated with RACGAP1 methylation levels, immune cell infiltration and reaction to immunotherapy, and chemoresistance. RACGAP1 could inhibit anti-tumor immunity and immunotherapy responses by fostering immune cell infiltration and cytotoxic T lymphocyte dysfunction. Significantly, we validated that RACGAP1 mRNA and protein were highly expressed in NPC. The Gene Expression Omnibus database revealed that elevated RACGAP1 expression was associated with shorter PFS in patients with NPC, and RACGAP1 potentially influenced cell cycle progression, DNA replication, metabolism, and immune-related pathways, resulting in the recurrence and metastasis of NPC. This study indicated that RACGAP1 could be a potential biomarker in pan-cancer and NPC.

Contrast Transthoracic Echocardiography Using 50% Glucose as a Contrast Agent for Screening of a Patent Foramen Ovale.

A patent foramen ovale (PFO) is considered a risk factor for neurologic events. The goal of the study described here was to assess the feasibility, advantages, diagnostic sensitivity and accuracy of contrast transthoracic echocardiography examination (cTTE) using 50% glucose as a contrast agent in comparison with the use of agitated saline as contrast to screen for PFO. In our study, we found that the peak time, effective duration and duration of microbubbles produced by 50% glucose were all longer than those produced by the physiologic saline. The sensitivities for detection of PFO with cTTE using physiologic saline and 50% glucose as contrast were 83% (20/24) and 100% (24/24), respectively. TEE suggested a PFO in 24 patients in two groups. Use of 50% glucose as a contrast agent in cTTE examination enables ultrasound technicians to easily observe the right-to-left shunt across the PFO. However, the sensitivities for detection of PFO with cTTE using 50% glucose did not statistically significantly differ from those for physiologic saline.

[Effect of vascular endothelial growth factor C and collagen triple helix repeat containing 1 expression on prognosis of rectal carcinoma patients].

OBJECTIVE: To explore the relationship of vascular endothelial growth factor C (VEGF-C) and collagen triple helix repeat containing 1 (CTHRC1) expression with the carcinogenesis and prognosis of rectal cancer. METHODS: Cancer tissue samples from 120 rectal cancer patients confirmed by pathology in the People's Hospital of Yichun City from September 2005 to September 2010 were included in the study. Expressions of CTHRC1 and VEGF-C were examined by immunohistochemistry and their correlations with clinicopathological features and prognosis were analyzed. RESULTS: The expression of VEGF-C was positively correlated with tumor size (r=0.943), TNM stages (r=0.784) and tumor differentiation (r=0.773) (all P<0.05). Similarly, the expression of CTRHC1 was also positively correlated with tumor size (r=0.829), TNM stages (r=0.632) and tumor differentiation (r=0.532) (all P<0.05). Rectal cancer patients with low expression of VEGF-C and CTHRC1 had significantly longer survival than those with high expression of VEGF-C and CTHRC1 [(40.0±1.3) vs. (35.4±0.5) months, P<0.01, (39.0±0.5) vs. (35.0±0.5) months, P=0.014]. CONCLUSION: VEGF-C and CTHRC1 may synergistically promote the invasion and metastasis of human rectal cancer, and provide evidence in predicting the prognosis of patients.

Molecular imaging of vulnerable plaques in rabbits using contrast-enhanced ultrasound targeting to vascular endothelial growth factor receptor-2.

PURPOSE: Increased neovascularization has been identified as a feature of atherosclerotic plaque vulnerability and can be traced by microbubble ultrasound contrast agents (UCA). We investigated the relationship between retention of a vascular endothelial growth factor receptor 2 (VEGFR-2) targeted UCA and VEGFR-2 expression in a vulnerable plaque model in rabbits. METHODS: Microbubbles targeting to VEGFR-2 were prepared by conjugation of biotinylated microbubbles with biotinylated VEGFR-2 antibody via streptavidin. Vulnerability was created by delivering recombinant p53 adenovirus to atherosclerotic plaques obtained in abdominal aorta by a high cholesterol diet and balloon endothelial injury. Twelve week later, the average video intensity of pre- and postcontrast ultrasound images was measured. VEGFR-2 expression and vascular density were quantified by immunohistochemical staining. RESULTS: Retention of targeted UCA in plaques was higher than that of nontargeted UCA (144 ± 18 dB versus 107 ± 9 dB; Z= -3.984, p = 0.000). VEGFR-2 expression was correlated with video intensity of targeted (r(2) = 0.78, p = 0.001), but not of nontargeted, UCA (r(2) = 0.17, p ≥ 0.05). CONCLUSIONS: The magnitude of the sonographic signal from retained VEGFR-2 targeted UCA correlates with VEGFR-2 expression. These results validate the use of targeted UCA for sonographic imaging of vulnerable abdominal artery plaques in rabbits.

Myocardium-targeted transplantation of mesenchymal stem cells by diagnostic ultrasound-mediated microbubble destruction improves cardiac function in myocardial infarction of New Zealand rabbits.

BACKGROUND: Therapeutic ultrasound-mediated microbubble destruction has been applied in the targeted delivery of genes, drugs and stem cells. We intended to study whether diagnostic US irradiating lipid-coated microbubble destruction combined with bone-marrow derived MSC infusion could enable the targeted delivery of MSCs into the myocardium and improve cardiac function of the myocardial infarction of New Zealand rabbits. METHODS: Diagnostic ultrasound was applied to the anterior chest for 10 min after intravenous injection of lipid-coated microbubble followed by infusion of BM-MSCs. Echocardiography, histological examination, and western blotting were performed 4 weeks after cell transplantation. RESULTS: The cardiac function (assessed by fractional shortening and ejection fraction) was markedly improved by US+Microbubble+MSC treatment. The number of capillaries stained by HE in US+Microbubble+MSC group (47+/-23) was much greater than that of the MSCs infusion group (26+/-7), US+Microbubble group(22+/-5) and PBS infusion group (19+/-10), P<0.01. US+Microbubble stimulation induced the expression of adhesion molecule (VCAM-1) in capillaries and enhanced the myocardial permeability of microvessels. US+Microbubble-mediated supply of MSCs increased the level of VEGF in ischemic myocardium. Area of cardiac fibrosis in the US+Microbubble+MSC group was significantly decreased by 25.6%,40.1% and 46.8% when compared with MSC infusion group, US+Microbubble group and PBS infusion group, respectively. CONCLUSIONS: This non-invasive cell delivery system may be useful as a novel and efficient approach for angiogenic cell therapy to the infarcted myocardium.

Value of myocardial regional perfusion on long-term function in collateral-dependent myocardium.

BACKGROUND: Collateral circulation is considered key for left ventricular (LV) function recovery in patients with chronic total occlusion (CTO). However, there are conflicting reports about the influence of collaterals on LV recovery after revascularization. METHODS: Echocardiographic assessment of regional myocardial perfusion, wall motion score (WMS), and left ventricular ejection fraction (LVEF) were performed in patients with angiographically visible collateral circulation of grades 2 and 3. RESULTS: The WMS and LVEF of group B (with presence of myocardial regional perfusion) were significantly improved at one month and six months compared to those of group A (with absence of myocardial regional perfusion). The correlation between myocardial regional blood flow and changes in WMS and LVEF was significant at 6 months in patients with angiographically visible collateral circulation of grade 2 and 3. Similar correlations were observed on myocardial contrast echocardiography (MCE) score index. CONCLUSION: Myocardial function recovery in patients with CTO is determined by myocardial regional perfusion. MCE has important value for prognosis and risk stratification in patients with CTO undergoing cardiac catheterization.

[Beneficial effects of probucol on endothelial function in patients with acute coronary syndrome].

OBJECTIVE: The study investigate the antioxidant probucol on endothelial function in patients with acute coronary syndrome (ACS). METHODS: A total of 49 ACS patients randomly received standard therapy plus probucol (P, n = 24) or standard therapy (C, n = 25). Plasma oxidized low-density lipoprotein (ox-LDL), nitric oxide (NO) and circulating endothelial cells (CEC) were measured. The brachial arterial hyperemia-induced flow mediated dilation (FMD) and sublingual nitroglycerin (NTG) mediated vasodilatations were measured by high resolution ultrasound. These variables were analyzed before and after 3 months therapy. RESULTS: Plasma NO and FMD was significantly increased after 3 months therapy than before therapy [(80.46 +/- 10.24) micromol/Lvs (48.46 +/- 12.24) micromol/L, P < 0.01; (13.46 +/- 1.20)% vs (7.45 +/- 1.02)%, P < 0.05, respectively], while the number of CEC and ox-LDL were significantly decreased (P < 0.01) in P group. These values were similar before and after 3 months in C group. The linear correlation analysis showed that plasma ox-LDL negatively correlated with NO (r = -0.574, P < 0.01) and FMD (r = -0.517, P < 0.01) and positively correlated with CEC (r = 0.385, P < 0.01) in patients received 3 months probucol therapy. CONCLUSIONS: Chronic antioxidant probucol therapy could improve endothelial function in patients with ACS.

Analysis of cytogenetic damage in rice seeds induced by energetic heavy ions on-ground and after spaceflight.

To analyze the biological effects of the space environment, we flew nine lines of rice seeds on the Chinese 20(th) recoverable satellite for a duration of 18 days. The same lines of seeds were also irradiated to low doses (2.0 mGy) of Carbon, or Neon or Iron ions (with different LET value of 13.3 keV/microm, 31 keV/microm and 500 keV/microm respectively) at National Institute of Radiological Sciences in Chiba, Japan. The total number of mitotic cells and chromosomal aberrations were analyzed. The mitotic index (MI) and the frequency of chromosomal aberration were evaluated in order to compare the cytogenetic damages from spaceflight and from exposure to similar doses of charged particle on the ground. The results of the present study show that the space environment and heavy energy ion can alter cell growth, and induce various chromosome aberrations including micronuclei, chromosomal bridges, fragments and laggards. With all the lines combined, the frequency of chromosome aberrations and MI in seeds flown in space are the highest. The effectiveness of cytogenetic damage from spaceflight (SP) and the heavy ion irradiations is SP > Fe > Ne > C.