Closer look at the juicy flesh inside.
Studies have shown that phytoceuticals in Mangosteen (in some cases known to be its xanthones) have properties such as: anti-tumor (shrinks tumors), anti-leukemia, antifungal (critical for all cancer patients), antibacterial (to protect DNA), antioxidants (at least two dozen different kinds of xanthones are in the mangosteen fruit), antiproliferation, kills cancer cells and causes apoptosis (programmed cell death) for some types of cancer. (Source: http://www.cancertutor.com/Cancer/Mangosteen.html)
So start eating more mangosteen. :)