title: Parasporins as new natural anticancer agents: a review.
abstract: In 1999 Mizuki and co-authors studied for the first time the parasporal inclusion proteins extracted from B. thuringiensis strains (a Gram-positive, soil-dwelling bacterium) for cytotoxic activity against human leukaemia T-cells. Later some other proteins with this unusual property to recognize human leukemic cells were isolated from this strain of bacteria and named parasporins. At present 6 types of parasporins are identified and characterized. This review summarizes the properties of these new potentially useful antitumor agents of natural origin. Various types of parasporins possess unique cytotoxic mechanisms against cancer cells. The cytotoxic activity for cancer cells makes parasporins possible candidates for anticancer agents in clinical oncology. Recently, genetic engineering was applied for the production of parasporins and the gene responsible for the production of the proteins was expressed in E. coli. However, there are virtually no data regarding the cytotoxic (antitumor) activity of parasporins in vivo. These relatively new cytotoxic proteins warrant further investigation, especially in rodents, for possible application in clinical oncology.
authors.affiliation: Scientific Center of Anti-Infectious Drugs, Almaty, Kazakhstan.
authors.forename: Almas
authors.initials: A
authors.lastname: Okassov
authors.forename: Armen
authors.initials: A
authors.lastname: Nersesyan
authors.forename: Sakae
authors.initials: S
authors.lastname: Kitada
authors.forename: Alexander
authors.initials: A
authors.lastname: Ilin
mesh_terms: D000818:Animals; D000970:Antineoplastic Agents / Q000009:adverse effects / Q000378:metabolism / Q000627:therapeutic use*; D001413:Bacillus thuringiensis / Q000235:genetics / Q000378:metabolism*; D001688:Biological Products / Q000009:adverse effects / Q000378:metabolism / Q000627:therapeutic use*; D004731:Endotoxins / Q000009:adverse effects / Q000096:biosynthesis / Q000235:genetics / Q000302:isolation & purification / Q000627:therapeutic use*; D005818:Genetic Engineering; D006801:Humans; D009369:Neoplasms / Q000188:drug therapy* / Q000473:pathology
chemical_list: D000970:Antineoplastic Agents; D001688:Biological Products; D004731:Endotoxins; C412914:parasporin