Protein-gold clusters-capped mesoporous silica nanoparticles for high drug loading, autonomous gemcitabine/doxorubicin co-delivery, and in-vivo tumor imaging.

Interaction of cyanidin-3-O-glucoside with three proteins.

Two decades of research in discovery of anticancer drugs targeting STAT3, how close are we?

Binding, unfolding and refolding dynamics of serum albumins☆☆☆

Astilbin (ASN) is a flavonoid compound isolated from the rhizome of Smilax china L. (Smilacaceae). It has many bioactivities, such as selective immunosuppression, antioxidant, anti-hepatic injury, etc., and is widely used in traditional Chinese medical treatments. The interaction of ASN with bovine serum albumin (BSA) was studied in a physiological buffer (pH = 7.40) using multi-spectroscopic techniques in combination with molecular docking methods. UV-vis absorption measurements proved that a ASN–BSA complex could be formed. Fluorescence data revealed that ASN could strongly quench the intrinsic fluorescence of BSA in terms of a static quenching procedure. The process of binding was spontaneous and the binding occurred mainly through hydrogen bonding and van der Waals forces. The distance r between donor (BSA) and acceptor (ASN) was calculated to be 4.80 nm based on Forster's non-radiative energy transfer theory. The binding constant (Ka = 7.31 × 104 mol L−1) and the number of binding sites (n ≈ 1) at 298 K suggested that ASN only occupied one site in BSA with high affinity. Moreover, the results of molecular docking indicated that ASN was more likely to be located in site I (sub-domain IIA) of BSA. The results of synchronous fluorescence and three-dimensional fluorescence spectra showed that ASN induced conformational changes of BSA. The findings would be beneficial for research on the transportation, distribution and some important bioactivities of ASN in the human body.

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Characterizing the binding interaction of astilbin with bovine serum albumin: a spectroscopic study in combination with molecular docking technology

In vitro study on the binding of gemcitabine to bovine serum albumin.

CXCL12/CXCR4 signaling plays important roles in tumor cell metastasis in many types of cancers, and CXCR4 is the key regulator of cell motility in bladder cancer. Emerging evidence suggests that transcription-3 (Stat3) activation is associated with bladder cancer cell growth and survival, while the relationship between CXCL12/CXCR4 signal and Stat3 activation remains unclear. In this study, expression analysis of bladder cancer and adjacent normal tissues showed that higher CXCR4 expression was associated with Stat3 phosphorylation. CXCR4 knockdown in bladder cancer T24 cells impaired CXCL12-induced cell invasion and Stat3 activation. Furthermore, blocking Stat3 activity with the chemical inhibitor Stattic inhibited CXCL12-triggered Stat3 phosphorylation and cell invasion in T24 cells, suggesting that Stat3 activation is required for CXCL12 function in the mobility of bladder cancer. Taken together, CXCR4 is necessary for CXCL12 signal transduction in bladder cancer, and CXCL12/CXCR4 promotes invasion of bladder cancer cells through activation of Stat3 transcriptional activity.

Hai-bo Shen

Papers

In vitro study on the binding of gemcitabine to bovine serum albumin.

CXCR4-mediated Stat3 activation is essential for CXCL12-induced cell invasion in bladder cancer