Bladder Cancer

Evidence-based overview of shikonin in bladder cancer, including PKM2-driven resistance reversal, necroptosis, and cisplatin sensitisation

Bladder cancer is the clearest resistance-reversal setting for shikonin.

The reason is simple.

Cisplatin resistance is a major clinical problem, and the shikonin mechanism lines up closely with it.

Why bladder cancer is a logical target

PKM2 rises in resistant cells

Cisplatin-resistant bladder-cancer cells show higher PKM2 expression than their cisplatin-sensitive parental lines.

That makes PKM2 part of the resistance phenotype, not just a background cancer marker.

Apoptosis is already impaired

Resistant bladder-cancer cells often have Bcl-2-related dysfunction that blocks normal apoptotic execution.

That is exactly where necroptosis becomes useful.

The key mechanistic evidence

In T24 cisplatin-resistant bladder-cancer cells, shikonin induced cell death that could not be blocked by the broad caspase inhibitor z-VAD-fmk.

That argues against simple apoptosis.

The same death signal was blocked by necrostatin-1, a RIPK1 inhibitor.

That supports true necroptosis.

This is the most important point in the bladder-cancer literature.

Shikonin does not just add more stress to already resistant cells.

It re-opens a death route they had not blocked.

PKM2 validation matters here

The case is stronger because it was not left as a pharmacology-only observation.

PKM2 knockdown by siRNA also restored cisplatin sensitivity.

That means the effect is much more likely to be target-relevant rather than random off-target toxicity.

Tissue relevance

Human bladder-cancer tissue samples have shown higher PKM2 expression in tumour tissue than in normal tissue.

That does not prove clinical benefit.

It does support the relevance of the target in real disease.

What remains unknown

no immune-competent animal work
no clinical trial data
no established schedule beside cisplatin
no subtype-specific mapping across muscle-invasive and non-muscle-invasive disease
no human pharmacokinetic evidence showing the needed tissue exposure

Bottom line

Bladder cancer offers the most mechanistically complete shikonin story in resistant disease.

PKM2 is elevated.

Shikonin inhibits it.

Necroptosis becomes accessible again.

That is why this page matters more than many loose “sensitisation” claims in natural-compound oncology.

References

Li Z et al. (2018). PKM2 inhibitor shikonin overcomes cisplatin resistance in bladder cancer via necroptosis. PMC / PLoS ONE.
https://pmc.ncbi.nlm.nih.gov/articles/PMC6231221/

This information is for education only. It is not medical advice, diagnosis, or treatment. Please speak with a qualified clinician before making changes to care, medication, or supplement use.