After struggling for days to summarize the third of these posts, I subsequently came across a brilliantly clear (and somewhat different) approach in a landmark paper by Hanahan and Weinberg. I've summarised its jist in a post entitled "The six characteristics of cancer".
The rest of the section is at present quite disparate, but contains two interesting topics. Firstly, we broach the subject of telomeres, which are virtually always disabled in cancer formation. Then, there is the fascinating question of how chemotherapy works.