Original Research

Biomedical Research and Therapy

, 3:23

First online:

Open Access This content is freely available online to anyone, anywhere at any time.

Effects of ricin extracted from seeds of the castor bean (ricinuscommunis) on cytotoxicity and tumorigenesis of melanoma cells

  • Ngo Ngoc TrungAffiliated withInstitute of Chemistry and Environment, High Command of Chemistry, Ministry of National DefenseDepartment of Biochemistry and Plant Physiology, VNU University of Science, Vietnam National University
  • , Nguyen Thi ThoAffiliated withDepartment of Biochemistry and Plant Physiology, VNU University of Science, Vietnam National UniversityThe Key laboratory of Enzyme and Protein Technology, VNU University of Science, Vietnam National University
  • , Bui Thi Thuy DungAffiliated withDepartment of Cell Biology, VNU University of Science, Vietnam National University
  • , Hoang Thi My NhungAffiliated withThe Key laboratory of Enzyme and Protein Technology, VNU University of Science, Vietnam National UniversityDepartment of Cell Biology, VNU University of Science, Vietnam National University
  • , Nguyen Dinh ThangAffiliated withDepartment of Biochemistry and Plant Physiology, VNU University of Science, Vietnam National UniversityThe Key laboratory of Enzyme and Protein Technology, VNU University of Science, Vietnam National University Email author 

Abstract

Ricin has been reported as a potential therapeutic agent for the treatment of various cancers due to its potency. In this study, we succeeded in isolating and purifying total ricin from seeds of the castor bean (ricinus communis) from Vietnam. We also revealed that total ricin showed strong cytotoxicity against melanoma cells; IC50 at 48h was 34.1 ng/mL for SKMEL28 cells and 5.2 ng/mL for HaCaT cells. We examined the ability of total ricin to inhibit tumorigenesis of SKMEL28 cells in vitro. At low concentrations (< 3ng/mL)total ricin did not cause death of HaCaT or SKMEL28 cells but strongly reduced the size of SKMEL28 tumor colonies formed in soft agar. The effect of ricin on tumorigenesis was also confirmed by apoptotic and immunoblot analyses. Our results showed that treatment with total ricin (3 ng/mL) resulted in decreased ERK and p-ERK expression in SKME28 cells but did not affect expression levels of thosegenes in HaCaT cells. We showed that, although ricin at 1 and 3 ng/mLdid not induce apoptosis of HaCaT cells, it significantly increased apoptosis of SKMEL28 up to 1.4 folds and 2.1 folds, respectively. The results from our study suggest that although ricin is listed as one of the most poisonous substances in nature, it has potential to be used as a drug for melanoma treatment.

Keywords:

Melanoma ricin ricinus communis tumorigenesis cytotoxicity