Evaluation of cytotoxic and anti-tumor activity of partially purified serine protease isolate from the Indian earthworm Pheretima posthuma

Objective:To isolate,partially purify and evaluate the cytotoxic and antitumor activity of a serine protease from the chosen Indian earthworm Pheretima posthuma.Methods:Whole animal extract was prepared and purified its protein constituents by size and charge based chromatographic separation techniques using Sephadex G-50 and DEAE-Cellulose resin respectively.Average molecular weight of the protein isolate was determined and analyzed for its cytotoxic property against Vero cells in different dilutions(1:20 and 1:40)and anti-tumor activity by MTT assay(a colorimetric assay)using breast cancer cell line MCF-7,with tamoxifen as standard.Results:One of the protein constituents after purification was characterized as serine protease by Caseinolytic plate diffusion assay.Average molecular weight of this purified isolate was determined,by SDS-PAGE analysis with standard protein ladder,as of 15 kDa.The performed tests suggested that the 15kDa fraction has potent cytotoxic activity and satisfactory antitumor activity as well in vitro.Conclusions:Exact molecular mechanism of the cytotoxic and antitumor activities is yet to be explored and currently we are working on ultra-purification and biophysical characterization of this fraction.Further investigation into the mechanism(s)of cytotoxic and antitumor activities at molecular level would be useful in treatment of various classes of cancer and viral infections in future.

Carbon nanotubes:A review on risks assessment,mechanism of toxicity and future directives to prevent health implication

Carbon nanotubes(CNTs)have tremendous applications in almost every walk of life;however,their harmful impacts on humans and the environment are not well addressed.CNTs have been used in various applications ranging from medical science to different engineering branches,to ease human life.Generally,the toxicological profile of CNTs under laboratory conditions cannot be assessed primarily in medical science due to the inconsistent availability of cytotoxic study data.CNT toxicity has been affected by many physicochemical properties(e.g.,size,type of functionalization),concentration,the extent of exposure,mode of exposure,and even the solvents/medium used to dissolve/disperse CNTs for their application.These inconsistencies arise due to the variation in synthesis methods as well as the mode of their human exposure.Besides their unlimited use in various fields,most of CNT toxicity aspects and mechanisms remain uncertain.Additionally,in-depth knowledge of CNTs toxicity is scarce,and the available literature shows dissimilarities in experimental data and exposure studies.To understand the toxicological issues,it is the need of the hour to provide insight into the published data,post-exposure studies,and various factors that may damage the cells due to CNTs toxicity.This review article analyses the hazardous potential through toxicological implications and summarizes the detailed mechanism(s)of CNTs studied on the different model organisms,including human cell lines.In this review article,we hypothesized that thorough knowledge of various aspects,as mentioned above,helps us design and develop possible strategies to reduce the toxicity of nanomaterial to make them safer and secure for humanity’s betterment.