Background: All cancers are leading causes of morbidity and mortality worldwide. The urgent need
for new lead compounds for the treatment of cancer is higher than ever before. Scientists search and try to discover
effective but less harmful new anti-tumor agents. Surgery, chemotherapy and radiation are the bestknown
methods for treating cancer, however, they continued to be limited. Rising efforts of the scientists toward
success of the drug discovery is increasing. Indole ring is considered as a key molecule existing in various
biologically active compounds. Indole derivatives are recognized to prevent proliferation and invasion of
many cancer cells.
Conclusion: This review presents the existing status and the very recent studies of indoles which have promising
activities such as derivatives of indole-3-carbinol, 3,3'-diindolylmethane (DIM), isatin etc. Their chemical
and biological behavior as well as a general overview of the anticancer activity is discussed.