I was actually unaware of this-- But melanoma is Yet Another Disease that has been associated with wayward ERV transcription and translation. Scientists have found inappropriate ERV RNA, protein, and anti-ERV antibodies in melanoma patients.
This is the first paper to break down 'melanoma' into subtypes (like 'cancer' is not monolithic, all 'melanomas' are not the same), and to compare those subtypes to normal tissue and benign naevus (non-cancerous birthmarks and moles).
This study made a smart move by looking for the inappropriate ERV expression in primary tissue (real tissue, not isolated blood cells-- a move other labs do for other diseases, which could end up being a mistake).
Interestingly, this group found increased full-length ERV expression in all the skin tissue they looked at, cancerous, normal, benign.
Differences started popping up when they looked for the RNA formally used to generate Env proteins (20.5% cancerous, 6.3% benign, 0% normal), and a retroviral accessory protein, Rec (23.1% cancerous, 0% benign, 0% normal). Env proteins can be pro-inflammatory, and Rec is potentially oncogenic itself.
Unfortunately, they did not look for Env or Rec proteins in any of their samples.
Cancers are messed up. They are wrong. Genetically, epigenetically, messed up.
It is possible ERV RNA expression is not any kind of cause of melanoma, but a mindless side-effect. It could be that these researchers are identifying junk cancer RNA that is never translated into ERV proteins, that in turn do not play a role in melanoma development.
And there is not much we can do therapeutically with this information until it is connected to protein, not RNA. They seem to think ERV RNA expression is trending with melanoma progression, but the end goal of research like this is to develop something like the HER-2 antibodies. Therapeutic antibodies that target ERV Env to flag the tumor for your immune system to attack it.
Research has to start somewhere, but dont be surprised if this leads to a novel cancer treatment... or never pans out to anything at all.