Reporters of Cancer Stem Cells as a Tool for Drug Discovery.

In view of the importance of cancer stem cells (CSCs) in chemoresistance, metastasis and recurrence, the biology of CSCs were explored in detail. Based on that, several modalities were proposed to target them. In spite of the several clinical trials, a successful CSC-targeting drug is yet to be identified. The number of molecules screened and entered for clinical trial for CSC-targeting is comparatively low, compared to other drugs. The bottle neck is the lack of a high-throughput adaptable screening strategy for CSCs. This review is aimed to identify suitable reporters for CSCs that can be used to identify the heterogeneous CSC populations, including quiescent CSCs, proliferative CSCs, drug resistant CSCs and metastatic CSCs. Analysis of the tumor microenvironment regulating CSCs revealed that the factors in CSC-niche activates effector molecules that function as CSC markers, including pluripotency markers, CD133, ABCG2 and ALDH1A1. Among these factors OCT4, SOX2, NANOG, ABCG2 and ALDH1A1 are ideal for making reporters for CSCs. The pluripotency molecules, like OCT4, SOX2 and NANOG, regulate self-renewal, chemoresistance and metastasis. ABCG2 is a known regulator of drug resistance while ALDH1A1 modulates self-renewal, chemoresistance and metastasis. Considering the heterogeneity of CSCs, including a quiescent population and a proliferative population with metastatic ability, we propose the use of a combination of reporters. A dual reporter consisting of a pluripotency marker and a marker like ALDH1A1 will be useful in screening drugs that target CSCs.

Self-assembled chitosan-zirconium phosphate nanostructures for adsorption of chromium and degradation of dyes.

Nano zirconium phosphate (ZrP) was synthesized hydrothermally using an autoclave and was further self-assembled with chitosan to form bionanocomposite CZrP. The structural characteristics of ZrP and CZrP were investigated by Fourier Transform Infrared (FT-IR), X-Ray Diffraction (XRD), Energy Dispersive X-Ray (EDX), X-Ray Photelectron Spectroscopy (XPS), Electron Spin Resonance (ESR), Raman spectroscopy and Transmission Electron Microscopy (TEM) techniques. During the course of characterization, unique surface defects and superoxide anions stabilized on ZrP and CZrP were observed for the first time. The potential of the synthesized nanocomposite was investigated for adsorption of Cr(VI), a copper phthalocynanine dye- Reactive blue-21 (RB-21), azo dye- Reactive Red 141 (RR-141), a xanthene dye-Rhodamine-6G as well as binary mixtures of the dyes. Further the potential of CZRP as catalyst for the hydrogen peroxide degradation of dyes was investigated. The dyes were degraded in ˜10 min and CZrP exhibited stability during multiple runs of degradation of the dyes.

Biopolymer capped silver nanoparticles with potential for multifaceted applications.

A sustainable, green and low cost method for the synthesis of silver nanoparticles at room temperature has been developed using guargum as a reducing and stabilizing agent. The synthesized silver nanoparticles (GAg) were characterized by UV-vis spectroscopy, FTIR, EDS, Raman, XRD and TEM. The interaction of the functional groups present in the biopolymer Guargum (G) with the silver nanoparticles (GAg) were responsible for the nanoparticle surface to function as active substrates for Surface Enhanced Raman Spectroscopic (SERS) detection of cationic and anionic dyes. The catalytic degradation of a copper phthalocyanine based dye- Reactive blue - 21(RB-21), an azo dye- Reactive red 141(RR-141) and a xanthene dye- Rhodamine - 6G(Rh-6G) as well as binary mixtures of the three dyes was evaluated using the synthesized nanoparticles. The catalyst also caused a significant reduction in Total Organic Carbon (TOC) suggesting the formation of smaller degraded products.