Development of a syngeneic in vivo tumor model and its use in evaluating a novel P-glycoprotein modulator, PGP-4008.

Multidrug resistance (MDR) is a phenomenon by which tumor cells develop reduced sensitivity to anticancer drugs, which often leads to the failure of cancer chemotherapy. A prominent mechanism of MDR is the overexpression of the multidrug efflux pump, P-glycoprotein (P-gp), that decreases the intracellular accumulation of many anticancer drugs, leading to increased tumor growth. Intensive efforts are under way to develop clinically useful MDR modulators that inhibit the function of P-gp for use in combination with established anticancer drugs.

Discovery and evaluation of inhibitors of human sphingosine kinase.

Sphingolipid-metabolizing enzymes control the dynamic balance of the cellular levels of bioactive lipids, including the proapoptotic compound ceramide and the proliferative compound sphingosine 1-phosphate. Accumulating evidence indicates that sphingosine kinase (SK) plays a pivotal role in regulating tumor growth and that SK can act as an oncogene. Despite the importance of SK for cell proliferation, pharmacological inhibition of SK is an untested means of treating cancer because of the current lack of nonlipid inhibitors of this enzyme.

Characterization of human palmitoyl-acyl transferase activity using peptides that mimic distinct palmitoylation motifs.

The covalent attachment of palmitate to proteins commonly occurs on cysteine residues near either N-myristoylated glycine residues or C-terminal farnesylated cysteine residues. It therefore seems likely that multiple palmitoyl-acyl transferase (PAT) activities exist to recognize and modify these distinct palmitoylation motifs. To evaluate this possibility, two synthetic peptides representing these palmitoylation motifs, termed MyrGCK(NBD) and FarnCNRas(NBD), were used to characterize PAT activity under a variety of conditions.

Inhibition of CYP 17, a new strategy for the treatment of prostate cancer.

Androgens are growth factors for approximately 80 percent of all prostate cancers. Suppressing androgen biosynthesis is therefore an important therapeutic strategy in order to inhibit tumor growth. Unfortunately, the drugs currently applied to lower androgen levels only affect testicular androgen production.

[Epidemic trends of pulmonary tuberculosis and case finding in Henan province].

Objective: Based on the data of the 4th national epidemiological survey in 2000 in Henan province, to obtain the trends of epidemic situation of pulmonary tuberculosis, and to analyze the methods of case finding.

Methods: The detection methods such as X-ray, sputum examination and PPD were used to diagnose active pulmonary tuberculosis from sampling population.

Results: The prevalence of active pulmonary tuberculosis is 497 per 100 000 population, the prevalence of smear positive pulmonary tuberculosis is 132 per 100 000 population.