Biosynthesized CdS Nanoparticle Induces ROS-dependent Apoptosis in Human Lung Cancer Cells.

BACKGROUND: The World Health Organization (WHO) estimated that the number of cancer-related deaths was 9.6 million in 2018 and 2.09 million deaths occurred by lung cancer. The American Institute for Cancer Research (AICR) also observed gender preferences in lung cancer, common in men than women. Since the past decade, nanoparticles have now been widely documented for their anti-cancer properties, which signifies that the development of nanotechnology would be a future diagnosis and treatment strategy for lung cancer. OBJECTIVE: The current study aimed to investigate the role of biosynthesized CdS nanoparticles (CdS NPs) in lung cancer cells (A549). Therefore, whether the CdS NP induces lung cancer cell death and the underlying mechanism is yet to be elucidated. METHODS: Literature was searched from various archives of biomedical and life science journals. Then, CdS NPs were biosynthesized and characterized by traditional and cutting-edge protocols. The CdS NP-mediated cell death was elucidated following standard protocols. RESULTS: CdS NPs induced cytotoxicity towards A549 cells in a dose-dependent manner. However, such a death mechanism does not go through necrosis. Intracellular reactive oxygen species (ROS) accumulation and mitochondrial membrane depolarization demonstrated that cell death is associated with intracellular ROS production. Furthermore, increased sub-G1 population, Bax expression, and decreased Bcl-2 expression revealed that the death was caused by apoptosis. CONCLUSION: CdS NPs promote apoptosis-mediated lung cancer cell death through ROS production.

Biosynthesized CdS nanoparticles disturb E. coli growth through reactive oxygen production.

AIMS: E. coli is a widely known model organism for life science research, especially in modern bio-engineering and industrial microbiology. The goal of our current study is to understand the growth inhibitory mechanism of biosynthesized CdS nanoparticles on E. coli bacteria. MAIN METHODS: Characterization of Aspergillus foetidus mediated CdS nanoparticles has been confirmed by Zeta potential, AFM and HRTEM analyses. Furthermore, we investigated the contribution of reactive oxygen species (ROS) and subsequently lipid peroxidation on the growth of E. coli. FACS and fluorometric studies were used to know the ROS production upon CdS nanoparticle treatment. Lipid peroxidation measurement was studied by thiobarbituric acid (TBA) assay. KEY FINDINGS: The synthesized CdS nanoparticles are roughly spherical, poly-dispersed in nature and are in ~15 nm of size. Furthermore, our investigation confirmed that the cells treated with 200 µl of CdS nanoparticles produce about 50 % more ROS and about 5 times of lipid peroxidation over control cells. In addition, the number of E. coli colony survival and cell filamentation strongly depend on such lipid peroxidation caused by ROS, which actually produced due to the interaction with biosynthesized CdS nanoparticles in growth media. SIGNIFICANCE: The current research would be helpful for the mechanistic understanding of growth inhibition of E. coli by CdS nanoparticle. This may be useful for industrial applications of E. coli like bacteria.