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Scientists discover cancer-fighting berry on tree that only grows in Far North Queensland - ABC News (Australian Broadcasting Corporation)

The article didn't mention what exactly this tree was but a bit of Google-fu, it's Hylandia dockrillii.

Pretty promising so far, however it will probably only be useful in easy to access cancer cells like in melanomas. Here's the article: PLOS ONE: Intra-Lesional Injection of the Novel PKC Activator EBC-46 Rapidly Ablates Tumors in Mouse Models