Still a while away from humans, and still only dealing with symptoms, this is still a big thing. Post-metastasis is the phase of cancer where survival rates  tend to drop (from 93% 5-year to 2.5-year with skeletal metastases in prostate cancer) and the severity of the treatments has to rise as you are treating more sites in the body.

So the finding of a small molecule that appears to prevent or slow metastasis is important. Fascinating to read how cancer cells move: I had popping off into the blood stream and floating to another site. Wrong (FYI macroketone stops actin binding together):

In order for a cancer cell to leave a primary tumor, fascin bundles
actin filaments together like a thick finger. The front edge of this
finger creeps forward and pulls along the rear of the cell. Cells crawl
away in the same way that an inchworm moves.