The present invention provides a compound for treating cancer including an isolated form of dibenzyl trisulfide (DTS) provided in an effective amount to act as an agent against human diseases, including various forms of cancer. The present invention also provides a compound for treating cancer including DTS isolated from Petiveria alliacea L. (guinea hen weed) for providing an effective, potent anti-proliferation and/or cytotoxic activity on a wide range of cancer cell lines. The present invention further provides DTS derivatives (e.g. DTS-albumin complexes) in effective dosage for providing a potent anti-proliferation and/or cytotoxic activity on a wide range of cancer cell lines. Additionally, the present invention provides methods of isolating and/or providing the DTS and/or its derivatives in an effective amount for providing a potent anti-proliferation and/or cytotoxic activity on cancer cell lines.