Biomedical subjects

Cheng Zhou

Publications and source records attributed to Cheng Zhou.

21 records · Page 2Linked to original sources

PubMed2003

[Significance of activated matrix metalloproteinase 2 (MMP2) in progression of bladder transitional cell carcinoma].

BACKGROUND & OBJECTIVE: Activated matrix metalloproteinase 2 (MMP2) play an important role in progression of tumors by degrading the extracellular matrix and basement membrane. However, the relationship between MMP2 activity in tumor tissue and tumor progression is still unclear in bladder transitional cell carcinoma (BTCC). The aim of this study was to evaluate the significance of MMP2 in the progression of BTCC. METHODS: The contents of activated MMP9 in 20 fresh BTCC samples and 4 normal bladder mucosa tissues were determined by semi-quantitative gelatine zymography and the results were analyzed. RESULTS: Of 20 BTCC tissues, activated MMP2 were detected in 19 cases and the activity was increased with the tumor grade and invasiveness. The activities of the MMP2 was 8896.5+/-1655.6(mg x ml(-1))(-1) in grade I BTCC(n=11),18 355.6+/-5 307.1(mg x ml(-1))(-1) in grade II BTCC(n=5), and 26,467.1+/-4 705.6 (mg x ml(-1))(-1) in gradeIII BTCC (n=3). The activities of MMP2 was 7 843.4+/-1 515.4 (mg x ml(-1))(-1) in tumors of Tis-T1 (n=10) and 21,295.6+/-3 297.9 (mg x ml(-1))(-1) in tumors of T2-T4 (n=9). No MMP2 was detected in normal bladder mucosa tissues. CONCLUSION: Activated MMP2 might play a key role in the progression of BTCC and the gelatine zymography is a useful method for the detection of activated type IV collagenase.

Carcinoma, Transitional Cell↗

PubMed2003

[Study of 8-OH-dG and its correlation with several cancer related gene in lung cancer tissues].

To investigate the relationship among 8-OH-dG and the development of human lung cancer and cancer related genes, an 8-OH-dG-specific monoclonal antibody and biotin-streptavidin immuno-staining were used to detect the 8-OH-dG in 150 cases of human lung cancer tissues, 120 adjacent lung tissues without cancer cells, 40 benign lung lesions and 40 normal lung tissues. The expressions of P53, C-MYC, K-RAS, BCL-2 and hTERT(human telomerase reverse transcriptase) were determined by immunohistochemistry and the relationship among the 8-OH-dG and these genes was analyzed. The 8-OH-dG were positive in 139 of 150 (92.7%) lung cancer specimens, and the percentage of adduct labeling cell in lung cancer specimens was (24.00 +/- 25.11)% (mean +/- SE). 21 of 120 (17.5%) adjacent lung tissues were adduct positive, and the percentage of adduct labeling cell was 2.42 +/- 5.98%. 4 of 40 (10.0%) benign lung lesions were adduct positive, and the percentage of adduct labeling cell was 0.80 +/- 1.30%, whereas 2 of 40 (5.0%) normal lung tissues were weak positive with 8-oh-dG, and the percentage of adduct labeling cell in this group was (0.34 +/- 1.01)%. The level of 8-OH-dG in lung cancer tissues was significantly higher than that of adjacent lung tissues, benign lung lesions and normal lungs (P < 0.01). The lung cancer patients were stratified by sex, age, cell types and smoking history, but these characteristics were not correlated with the level of 8-OH-dG. In the investigation of the relationship between the 8-OH-dG and five cancer related genes, higher 8-OH-dG levels were observed in lung cancer patients with over-expression of K-RAS and BCL-2 than those of negative expressed patients (P-value were 0.035 and 0.034 respectively), whereas the expression of P53, C-MYC and hTERT were not correlated with level of 8-OH-dG. 8-OH-dG was an important biomarker that may reflect the oxidative DNA damages of cells, and 8-OH-dG may affect K-RAS and BCL-2 genes in the carcinogenesis of lung cancer.

8-Hydroxy-2'-Deoxyguanosine↗

PubMed2002

Quantum calculation of highly excited vibrational energy levels of CS2(X) on a new empirical potential energy surface and semiclassical analysis of 1:2 Fermi resonance.

We report a refined potential energy function for the ground electronic state of CS2 based on a least-squares fitting to several low-lying experimental vibrational frequencies. Energy levels up to 20,000 cm(-1) have been obtained on this empirical potential using the Lanczos algorithm and potential optimized discrete variable representation. Among them, 329 levels below 10,000 cm(-1) are assigned with approximate normal mode quantum numbers (n1, n(0)2, n3), based on expectation values of one-dimensional (1D) reference Hamiltonians. An effective Hamiltonian is extracted from these assigned levels. The agreement with experimental data, including those of several isotopically substituted species, is excellent. In addition, some Fermi and anharmonic resonances are analyzed. The nearest neighbor level spacing and delta3 distributions indicated that the vibrational spectrum of CS2 is largely regular in the energy range up to 20,000 cm(-1). Semiclassical phase space analysis, including bifurcation analysis of the spectroscopic Hamiltonian, is used to interpret subtle anomalies signaled by expectation values used in normal mode assignments. The meaning of Fermi resonance is clarified by contrasting the semiclassical analysis of CS2 and CO2.

Carbon Disulfide↗