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Cheng Cao

Publications and source records attributed to Cheng Cao.

At least 19 recordsLinked to original sources
PubMed2025

Chromosomal instability by low-coverage whole-genome sequencing assay predicts prognosis in bladder cancer patients underwent radical cystectomy.

PURPOSE: To investigate chromosomal instability (CIN) in tumor tissue from radical bladder resection and to evaluate whether it can be used as a biomarker for the molecular typing of (BC). METHODS: DNA was extracted from formalin-fixed paraffin-embedded samples of 50 BC patients who were followed up to March 23 2023 using the Qiagen nucleic acid kits. We analyzed CIN in tumor of bladder by low-coverage whole genome sequencing (LC-WGS). Kaplan-Meier log-rank test was used to perform survival analysis. The association between variables and overall and progression-free survival was analyzed using the Cox proportional hazards model. RESULTS: There were 44 genome segments with statistically significant changes in copy number. CIN was significantly correlated with tumor stage, lymph node metastasis, relapse and survival status. Patients with high CIN were found to have a worse survival, with a median overall survival (OS) of 15 months. In addition, patients with high CIN were more likely to relapse, with a median progression-free survival (PFS) of 7 months. Patients with low CIN showed better OS and PFS. However, there was no significant difference in OS and PFS between T2 and T3-T4 patients. Multivariate cox regression analysis showed that high CIN was an independent predictor of OS, and high CIN and muscle invasion were independent predictors of PFS. Furthermore, patients with abnormal copy number of a single chromosome also had a poor prognosis, with a median survival of 14-30 months for OS and 5-10 months for PFS, while negative patients had a better prognosis. CONCLUSION: CIN was significantly correlated with tumor stage, lymph node metastasis, relapse and survival status of BC. Patients with high CIN or abnormal copy numbers of a single chromosome have a poor prognosis. CIN might be better than T stage in predicting the prognosis of patients with BC. Molecular typing of CIN can be used as an independent prognostic factor for BC.

Humans↗
PubMed2006

Interaction between c-Abl and Arg tyrosine kinases and proteasome subunit PSMA7 regulates proteasome degradation.

Proteasome-mediated proteolysis is a primary protein degradation pathway in cells. The present study demonstrates that c-Abl and Arg (abl-related gene) tyrosine kinases associate with and phosphorylate the proteasome PSMA7 (alpha4) subunit at Tyr-153. Consequently, proteasome-dependent proteolysis is compromised. Notably, cells expressing a phosphorylation mutant of PSMA7(Y153F) display impaired G1/S transition and S/G2 progression, highlighting the biological significance of tyrosine phosphorylation of a proteasome subunit as an important cellular regulatory control.

Animals↗
PubMed2006

[Atherosclerotic aortic ulcers monitoring by electron beam CT or multi-slice CT].

OBJECTIVE: To evaluate the evolution of medically treated atherosclerotic aortic ulcers by computed tomography (CT). METHODS: Thirty-five patients (31 men and 4 women, aged from 40 to 79 years, mean 56.2 +/- 10.8 years) with known aortic ulcers were monitored by CT (follow up time 7 - 730 days, mean 135 days), 80 - 100 ml contrast media (Ultravist 300 or 320, or Omnipaque 300 or 320 mg/ml) was injected with a rate of 3.5 - 4.5 ml/s. The scan delayed time was 18 - 30 s. Ulcers dimensions were measured according to maximum depth, maximum length and maximum width. RESULTS: Thirty-one patients with intramural hematomas and 1 patient with atherosclerotic aortic arch aneurysm without intramural hematoma were medically treated and another 3 patients were surgically treated. Intramural hematoma regression was monitored in 31 medically treated patients with intramural hematomas. CT was repeated at 2 weeks, 3 and 6 months. Intramural hematoma resolved gradually during follow up [thickness: (7.69 +/- 4.24) mm at 3 months, (3.06 +/- 1.67) mm at 6 months, P < 0.05 vs. 1st CT: (11.96 +/- 4.16) mm while ulcer maximum depth (11.17 +/- 6.03) mm at 3 months, (11.35 +/- 5.59) mm at 6 months, P < 0.05 vs. 1st CT: (7.36 +/- 6.61) mm, maximum width (14.40 +/- 6.35) mm at 3 months, (18.55 +/- 10.94) mm at 6 months, P < 0.05 vs. 1st CT: (7.15 +/- 6.39) mm, maximum length (17.12 +/- 7.15) mm at 3 months, (18.13 +/- 10.89) mm at 6 months, P < 0.05 vs. 1st CT: (11.64 +/- 10.06) mm increased progressively during follow-up]. CONCLUSION: CT was a useful tool for deflecting atherosclerotic aortic ulcers and monitoring therapeutic effects.

Adult↗
PubMed2005

Ubiquitination and degradation of the Arg tyrosine kinase is regulated by oxidative stress.

The c-Abl and Arg nonreceptor tyrosine kinases are activated in the response of cells to oxidative stress. The present studies demonstrate that treatment of cells with 0.1 mM H2O2 is associated with increased tyrosine phosphorylation of Arg and little effect on Arg levels. By contrast, exposure to 1.0 mM H2O2 decreased Arg phosphorylation. Treatment with 1.0 mM H2O2 was also associated with ubiquitination and degradation of Arg. The results show that Arg is stabilized in response to 0.1 mM H2O2 by autophosphorylation of Y-261, consistent with involvement of the Arg kinase function in regulating Arg levels. The results further demonstrate that c-Abl-mediated phosphorylation of Arg on Y-261 similarly confers Arg stabilization. In concert with these results, phosphorylation of Arg on Y-261 blocked H2O2-induced ubiquitination and thereby Arg degradation and inactivation. These findings demonstrate that Arg phosphorylation and degradation are differentially regulated by the degree of oxidative stress, and that Arg stability is conferred by phosphorylation of Y-261.

Arginine↗
PubMed2005

Boosting immune response to hepatitis B DNA vaccine by coadministration of Prothymosin alpha-expressing plasmid.

DNA vaccines induce protective humoral and cell-mediated immune responses in several animal models. However, compared to conventional vaccines, DNA vaccines usually induce poor antibody responses. In this study, we report that coadministration of a hepatitis B virus (HBV) DNA vaccine with prothymosin alpha as an adjuvant improves antibody responses to HBV S antigen. We also observed higher seroconversion rates and higher antibody titers. Prothymosin alpha appears to increase the number and affinity of hepatitis B surface antigen-specific, gamma interferon-secreting T cells and to enhance cellular immune response to the PreS2S DNA vaccine. Interestingly, administering the DNA separately from the prothymosin alpha plasmid abrogated the enhancement of DNA vaccine potency. The results suggest that prothymosin alpha may be a promising adjuvant for DNA vaccines.

Adjuvants, Immunologic↗
PubMed2005

Retrospective serological investigation of severe acute respiratory syndrome coronavirus antibodies in recruits from mainland China.

Different assays were used to analyze 1,621 serum specimens collected from military recruits from the People's Republic of China in 2002 for severe acute respiratory syndrome (SARS) coronavirus antibodies. The results demonstrated that the subjects either had rarely been exposed to the virus before the 2003 SARS outbreak or had not been exposed but the nucleocapsid protein cross-reacted with other antibodies in humans.

Adolescent↗
PubMed2005

[RNA interference and its application in inhibiting HIV-1 infection].

RNA interfering (RNAi)--one of the most exciting discoveries in biology in the last couple decades has quickly become one of the most powerful and indispensable tools in the molecular biologist's toolkit. It is an important protection mechanism in cells, by which animals and plants defend viral infection and inhibit viral replication. RNAi is the process of sequence-specific, posttranscriptional gene silencing in animals and plants initiated by dsRNA that is homologous to the silenced gene and has emerged as a powerful tool to silence gene expression in multiple organisms. It has recently been shown that double-stranded, small interfering RNAs (siRNAs) of 21-25 nucleotides can be transfected into relevant cells to target specific RNAs. In mammalian cells it is known that dsRNA 30 base pairs or longer can trigger interferon responses that are intrinsically sequence-nonspecific, thus limiting the application of RNAi as an experimental and therapeutic agent. Duplexes of 19-25 nts (nucleotides) siRNA with short 3' overhangs, however, can efficiently inhibit gene expression in a sequence-specific manner in cultured mammalian cells. This approach was utilized to inhibit human immunodeficiency virus type I (HIV-1) infection in human cells. The in vitro experiments indicate that RNAi as a powerful antiviral tool will bring a promising future to gene therapy for virus disease.

Animals↗
PubMed2005

[The clinical application of electron beam tomography in the diagnosis of pulmonary thromboembolism].

OBJECTIVE: To evaluate the clinical significance of electron beam computerized tomography (EBCT) in the diagnosis and differential diagnosis of pulmonary thromboembolism (PTE). METHODS: EBCT was performed before March 2004 in 114 consecutive patients with clinically suspected pulmonary vascular diseases, including 76 patients with PTE, 29 with pulmonary arteritis, 5 with primary pulmonary arterial tumor, and 4 with pulmonary arterial invasion by lung or mediastinal carcinoma. EBCT was performed using Imatron C-150 scanner with enhanced continuum volume scan (CVS). The slice thickness was 3 mm with scanning time of 0.1 s. The total amount of contrast media (Omnipaque-300) used was 50-100 ml, with flow rates of 3.0-4.0 ml/s and a delay time of 14-25 s. RESULTS: Deep venous thrombosis (DVT) was confirmed in 58 (76.3%) of the 76 patients with PTE (52 men and 24 women), 8 (10.6%) of them without apparent causes. Of the 2 356 pulmonary arterial branches observed in the 76 cases, 1,668 branches (70.8%) showed signs of PTE, with 545 branches (32.7%) of the central pulmonary arteries and 1 123 branches (67.3%) of the peripheral pulmonary arteries. Central type filling defect, such as the "railway sign" or the "drifting sign", was specific for acute thrombosis. Thrombus calcification was a specific sign of chronic PTE. Indirect signs of PTE included mosaic signs, enlargement of the right ventricle and atrium, pulmonary artery enlargement, pulmonary infarction, pericardial and/or pleural effusion, pulmonary atelectasis and pulmonary consolidation. Pulmonary arteritis (including pulmonary arterial involvement in Takayasu arteritis) was diagnosed by EBCT in 27 (93.1%) of the 29 patients, in which the diagnosis was confirmed by pulmonary angiography in 16, and clinically in 13 Patients. Of the 5 patients with primary pulmonary arterial tumor confirmed by pathology, 1 was misdiagnosed by EBCT. Of the 4 patients with pulmonary arterial involvement by lung or mediastinal carcinoma, 3 were confirmed by surgery and 1 by pulmonary angiography. CONCLUSIONS: DVT and PTE are different manifestations of one disease. The diagnostic strategy aims to detect thrombosis in the pulmonary arteries and in the deep veins of the lower limbs at the same time. EBCT is an effective and non-invasive examination in the diagnosis and differential diagnosis of PTE. By EBCT, acute and chronic thrombi can be initially differentiated, and changes in lung parenchyma, mediastinum, and the pulmonary and systemic arterial walls can be observed, and therefore more valuable radiological information can be collected for clinical decision-making.

Adult↗
PubMed2005

[Enhancement of immune responses to hepatitis B DNA vaccine by superantigen SEA in mice].

To investigate the adjuvant effect of plasmid DNA encoding superantigen SEA (D227A) (pmSEA) on immune responses induced by HBV DNA vaccine containing HBV preS2 and S antigen in BABL/c (H-2d). BALB/c mice were immunized intramuscular injection with HBV DNA vaccine (pHBVS2S) mixed with or without pmSEA plasmid. Antibodies againat HBV PreS2 and S antigen in the sera were accessed by Anti-HBs ELISA, and the HBsAg specific cytotoxic T lymphocytes (CTLs) activity was determined by 5 Chromium Release Assay. The HBs peptide-specific IFN-gamma secreting T cells were detected by ELISPOT. Anti-HBs antibody titers and CTLs activity in mice immunized with pmSEA + pHBVS2S group were significant higher (P < 0.05) than pHBVS2S DNA vaccine group. The ratio of IgG1/IgG2a (0.282) was apparently different from the group immunized with peptide (10). Mice immunized with HBV DNA vaccine plus adjuvant produce higher titer of IgG1 and IgG2a antibodies against HBV S antigen 1.36 and 1.73 time higher than that without adjuvant respectively. HBs peptide--specific IFN-gamma secreting T cells increased 2 - 3 times by the pmSEA adjuvant, compared to DNA vaccine group. HBV DNA vaccine (pHBVS2S) induces humoral and cellular immuno-responses in BALB/c mice, and the responses could be significantly boasted by the plasmid encoding mSEA. Therefore the pmSEA was a potential adjuvant for DNA vaccines.

Adjuvants, Immunologic↗
PubMed2005

Homodimerization of the c-Abl protein tyrosine kinase.

The c-Abl nonreceptor tyrosine kinase is activated in the cellular responses to genotoxic, oxidative and other forms of stress. Using tagged forms of c-Abl, the present studies demonstrate that c-Abl forms homodimers in cells. The results show that the c-Abl N-terminal regions interact with the corresponding C-terminal regions of both partners in the dimmer. Specifically, the c-Abl SH3 domain binds to a proline-rich motif at amino acids 958-982 in the c-Abl C-terminal region. Deletion of the proline-rich motif disrupts dimmer formation. These findings provide the first evidence that c-Abl forms homodimers and indicate that homodimerization can contribute to the regulation of c-Abl activity.

Humans↗
PubMed2004

Proteomic analysis on structural proteins of Severe Acute Respiratory Syndrome coronavirus.

Recently, a new coronavirus was isolated from the lung tissue of autopsy sample and nasal/throat swabs of the patients with Severe Acute Respiratory Syndrome (SARS) and the causative association with SARS was determined. To reveal further the characteristics of the virus and to provide insight about the molecular mechanism of SARS etiology, a proteomic strategy was utilized to identify the structural proteins of SARS coronavirus (SARS-CoV) isolated from Vero E6 cells infected with the BJ-01 strain of the virus. At first, Western blotting with the convalescent sera from SARS patients demonstrated that there were various structural proteins of SARS-CoV in the cultured supernatant of virus infected-Vero E6 cells and that nucleocaspid (N) protein had a prominent immunogenicity to the convalescent sera from the patients with SARS, while the immune response of spike (S) protein probably binding with membrane (M) glycoprotein was much weaker. Then, sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) was used to separate the complex protein constituents, and the strategy of continuous slicing from loading well to the bottom of the gels was utilized to search thoroughly the structural proteins of the virus. The proteins in sliced slots were trypsinized in-gel and identified by mass spectrometry. Three structural proteins named S, N and M proteins of SARS-CoV were uncovered with the sequence coverage of 38.9, 93.1 and 28.1% respectively. Glycosylation modification in S protein was also analyzed and four glycosylation sites were discovered by comparing the mass spectra before and after deglycosylation of the peptides with PNGase F digestion. Matrix-assisted laser desorption/ionization-mass spectrometry determination showed that relative molecular weight of intact N protein is 45 929 Da, which is very close to its theoretically calculated molecular weight 45 935 Da based on the amino acid sequence deduced from the genome with the first amino acid methionine at the N-terminus depleted and second, serine, acetylated, indicating that phosphorylation does not happen at all in the predicted phosphorylation sites within infected cells nor in virus particles. Intriguingly, a series of shorter isoforms of N protein was observed by SDS-PAGE and identified by mass spectrometry characterization. For further confirmation of this phenomenon and its related mechanism, recombinant N protein of SARS-CoV was cleaved in vitro by caspase-3 and -6 respectively. The results demonstrated that these shorter isoforms could be the products from cleavage of caspase-3 rather than that of caspase-6. Further, the relationship between the caspase cleavage and the viral infection to the host cell is discussed.

Amino Acid Sequence↗
PubMed2004

Antibody responses against SARS-coronavirus and its nucleocaspid in SARS patients.

BACKGROUND: SARS-Cov is the etiologic agent of severe acute respiratory syndrome. An understanding of the antibody responses to the viral components is very important for diagnosis and vaccine development. OBJECTIVE: The spectrum of SARS-specific antibody profiles in SARS patients was investigated from 7 to 210 days after the onset of the symptoms. STUDY DESIGN: Serial serum samples from 14 SARS patients were isolated from 7 to 210 days after the onset of the symptoms, and were tested for anti-viral IgG and IgM by indirect immunofluorescence tests (IFA), anti-nucleocaspid antibody by ELISA tests and viral neutralization. RESULTS: Anti-viral (IgG) and anti-nucleocaspid antibodies were observed in 13 of 14 patients at 14 days after the onset of symptoms, and in all 14 patients at 30-210 days thereafter. Anti-viral antibody (IgM) was detected maximally at 30 days, later than that for the IgG class. IgM antibody declined and became undetectable between 60 to 180 days after the onset of the symptoms. Neutralizing viral antibodies were demonstrated in the sera from all of the patients with SARS symptoms. CONCLUSIONS: Anti-viral IgG, IgM, and anti-nucleocaspid antibodies were detected 7-30 days in patients after the onset of SARS symptoms. Anti-viral IgM antibodies disappeared earlier than IgG. Viral neutralization was demonstrated in the sera from the convalescent patients.

Adult↗
PubMed2004

Profile of antibodies to the nucleocapsid protein of the severe acute respiratory syndrome (SARS)-associated coronavirus in probable SARS patients.

Profiles of antibodies to the nucleocapsid protein of the severe acute respiratory syndrome (SARS)-associated coronavirus in 445 probable SARS patients and 3,749 healthy people or non-SARS patients were analyzed by antigen-capturing enzyme-linked immunosorbent assay. Antinucleocapsid antibodies were elucidated in 17.5% of the probable SARS patients 1 to 7 days after the onset of symptoms and in 80% of the patients 8 to 14 days after the onset. About 90% of the probable SARS patients were positive 15 or more days after illness. Antibody titers increased up to 70 days, and high antibody titers were maintained at least for another 3 months. Of the healthy people and non-SARS patients, only seven (0.187%) were weakly positive.

Adult↗
PubMed2004

[Induction of protective immunity in rhesus monkey by inoculation with recombinant fusion protein of cholera toxin B subunit-multivalent epitopes of Plasmodium falciparum].

Rhesus monkeys (5 in each group) were inoculated with recombinant fusion protein of cholera toxin B subunit and multi-valent epitopes of Plasmodium falciparum intranasal or intramuscular (i.m.). Immune-responses and protective effect were evaluated. The antibody titer (Geometry mean) against CTB reached 1:512 (intranasal) and 1:10000 (i.m.) 14 day after 3rd immunization, and antibodies against P. falciparum were also elucidated, the titers in i.m. group were also significantly higher than that in intranasal group. The monkeys were challenged with 1.25 x 10(8) sporozoites of P. cynomolgi, Patent infection was observed in all 5 monkeys in control group inoculated with PBS in 10 - 14 days after challenge. Patent infection was also observed in 5 animals inoculated via intranasal and 2 animals in intramuscular group 19th days after challenge, But the infection last only 4 days in 3 animals in intranasal group and 2 animals in intramuscular group. The results demonstrated that the vaccine candidate could induce protective immune-responses in rhesus monkey against the challenge of P. cynomolgi.

Animals↗
PubMed2003

Catalase is regulated by ubiquitination and proteosomal degradation. Role of the c-Abl and Arg tyrosine kinases.

Catalase is a major effector in the defense of aerobic cells against oxidative stress. Recent studies have shown that catalase activity is stimulated by the c-Abl and Arg tyrosine kinases. Little, however, is otherwise known about the mechanisms responsible for catalase regulation. The present work demonstrates that mouse cells deficient in both c-Abl and Arg exhibit increased catalase stability. The results also show that catalase is subject to ubiquitination and degradation by the 26S proteosome. Significantly, ubiquitination of catalase is dependent on c-Abl- and Arg-mediated phosphorylation of catalase on both Y231 and Y386. In concert with these results, human 293 cells expressing catalase mutated at Y231 and Y386 exhibit attenuated levels of reactive oxygen species when exposed to hydrogen peroxide. These findings indicate that, in addition to stimulating catalase activity, c-Abl and Arg promote catalase degradation in the oxidative stress response.

Animals↗
PubMed2003

Glutathione peroxidase 1 is regulated by the c-Abl and Arg tyrosine kinases.

The c-Abl and Arg tyrosine kinases are activated in the cellular response to oxidative stress. The present studies demonstrate that c-Abl and Arg associate with glutathione peroxidase 1 (GPx1) and that this interaction is regulated by intracellular oxidant levels. The c-Abl and Arg SH3 domains bind directly to a proline-rich site in GPx1 at amino acids 132-145. GPx1 also functions as a substrate for c-Abl- and Arg-mediated phosphorylation on Tyr-96. The results further show that c-Abl and Arg stimulate GPx activity and that these kinases contribute to GPx-mediated protection of cells against oxidative stress. Our findings provide the first evidence that GPx1 is regulated by a signaling pathway that is activated in the oxidative stress response.

Animals↗
PubMed2003

Catalase activity is regulated by c-Abl and Arg in the oxidative stress response.

The Abl family of mammalian non-receptor tyrosine kinases includes c-Abl and Arg. Recent studies have demonstrated that c-Abl and Arg are activated in the response of cells to oxidative stress. This work demonstrates that catalase, a major effector of the cellular defense against H2O2, interacts with c-Abl and Arg. The results show that H2O2 induced binding of c-Abl and Arg to catalase. The SH3 domains of c-Abl and Arg bound directly to catalase at a P293FNP site. c-Abl and Arg phosphorylated catalase at Tyr231 and Tyr386 in vitro and in the response of cells to H2O2. The functional significance of the interaction is supported by the demonstration that cells deficient in both c-Abl and Arg exhibit substantial increases in H2O2 levels. In addition, c-abl-/- arg-/- cells exhibited a marked increase in H2O2-induced apoptosis compared with that found in the absence of either kinase. These findings indicate that c-Abl and Arg regulate catalase and that this signaling pathway is of importance to apoptosis in the oxidative stress response.

Apoptosis↗