Determination of SNX-2112, a selective Hsp90 inhibitor, in plasma samples by high-performance liquid chromatography and its application to pharmacokinetics in rats

Analytical and bioanalytical HPLC method for simultaneous estimation of 5-fluorouracil and sonidegib

Aim: To develop a new sensitive RP-HPLC method for simultaneous estimation of 5-fluorouracil (5-FU) and sonidegib (SDG). Materials & methods: Analytical and bioanalytical methods for simultaneous quantification of 5-FU and SDG in bulk, nanoformulations and in rat plasma were developed and validated using a gradient elution technique. Results: Separation of the analytes was effected on a Luna^® C18 LC column using a mobile mixture comprising acetonitrile and acidified water. 5-FU and SDG were extracted from plasma matrix using liquid-liquid extraction. The applicability of the method was verified through single-dose oral pharmacokinetic study in Wistar rats. Conclusion: The developed methods allow a specific, sensitive and steady analytical procedure for the simultaneous estimation of 5-FU and SDG in nanoformulations and biological matrix.

A novel heterogeneous network-based method for drug response prediction in cancer cell lines

An enduring challenge in personalized medicine lies in selecting a suitable drug for each individual patient. Here we concentrate on predicting drug responses based on a cohort of genomic, chemical structure, and target information. Therefore, a recently study such as GDSC has provided an unprecedented opportunity to infer the potential relationships between cell line and drug. While existing approach rely primarily on regression, classification or multiple kernel learning to predict drug responses. Synthetic approach indicates drug target and protein-protein interaction could have the potential to improve the prediction performance of drug response. In this study, we propose a novel heterogeneous network-based method, named as HNMDRP, to accurately predict cell line-drug associations through incorporating heterogeneity relationship among cell line, drug and target. Compared to previous study, HNMDRP can make good use of above heterogeneous information to predict drug responses. The validity of our method is verified not only by plotting the ROC curve, but also by predicting novel cell line-drug sensitive associations which have dependable literature evidences. This allows us possibly to suggest potential sensitive associations among cell lines and drugs. Matlab and R codes of HNMDRP can be found at following https://github.com/USTC-HIlab/HNMDRP.

Curcumin inhibits human cytomegalovirus by downregulating heat shock protein 90

Curcumin is a traditional Chinese medicine extracted from the rhizome of the herb Curcuma longa, which exhibits anti-human cytomegalovirus (HCMV) activity, however, the underlying mechanism remains to be elucidated. The present study reported that the pharmacogenomics of curcumin are similar to that of the antiviral drug, geldanamycin, which targets heat shock protein 90 (Hsp90). Comparative analysis of 3,000 clinical drugs demonstrated that curcumin had a positive association with the gene expression profiles of several drugs, among which the pharmacogenomics of the antiviral drug, geldanamycin, were most similar to that of curcumin. Molecular docking simulation analysis revealed that curcumin fit well in the binding pocket of Hsp90, with hydrogen bonds, hydrophobic interactions and conjugation to maintain adhesion. Consistently, HCMV infection of human embryonic lung fibroblast cells resulted in increased expression of Hsp90α, which was significantly inhibited by treatment with curcumin. These findings suggested that targeting Hsp90 contributed to the anti‑HCMV activity of curcumin.

Inhibition of heat shock protein 90 suppresses squamous carcinogenic progression in a mouse model of esophageal cancer

PURPOSE

Heat shock protein 90 (Hsp90), a potential therapeutic target, has been widely recognized in vitro and in vivo in immunodeficient mice. Here, we aimed to evaluate the role of Hsp90 in an immunocompetent mouse model of esophageal squamous cell cancer (ESCC).

METHODS

The carcinogen 4-nitroquinoline 1-oxide (4NQO) was used to induce ESCC in C57BL/6 mice. Cancer progression was analyzed through observation of appearance, hematoxylin-eosin staining, immunohistochemical detection, and terminal dUTP nick-end labeling analysis.

RESULTS

4NQO led to the progressive appearance of preneoplastic and tumoral lesions in the esophagus, with 100 % incidence of ESCC in situ occurring only after 16 weeks of carcinogen exposure. Most of these lesions evolved spontaneously into highly invasive ESCC even after 4NQO withdrawal (weeks 16-22). Interestingly, there was marked upregulation of Hsp90 and its client proteins in tumoral lesions at 22 weeks. Hsp90 inhibition by intraperitoneal injection of SNX-2112 over the following 2 weeks downregulated AKT and cyclin D1 expression, leading to significant reduction in tumor incidence and prevention of ESCC progression. Moreover, SNX-2112 treatment decreased proliferating cell nuclear antigen expression and increased the number of apoptotic cells in ESCC tissues.

CONCLUSIONS

Our in vivo findings support the contribution of Hsp90 to ESCC progression, which was achieved by stimulating apoptosis and inhibition of cell proliferation, and provide a strong rationale for further evaluation of Hsp90 inhibitors for treating ESCC.