Using mice models, researchers studied about the chimera virus, produced in Instituto de Medicina Molecular (IMM) Lisboa. Molecules to treat cancer caused by human herpesvirus infection could be studied using the chimera virus.

The herpes viruses have the ability to infect host for lifetime and also result in cancer in certain cases. The herpes viruses include herpes simplex, chickenpox, cytomegalovirus, Epstein-Barr and Kaposi Sarcoma herpesvirus.

In Kaposi Sarcoma infection, the cells’ viability is reliant on the survival of the virus. This is its Achilles heel, hence virus elimination can decline cancer proliferation, in turn, cure cancer.

Further, the protein of the Kaposi virus, essential for retaining the infection was studied. This study was led by Pedro Simas (IMM) and Kenneth Kaye (Harvard) in collation with a team from Harvard-Medical School, and they found that virus loses its ability to cause cancer without this protein (LANA).

When LANA is cloned into a virus alike to Kaposi, the researchers found that it preserves its functionality. However, it was assumed that evolutionary divergence amongst human and other animal viruses could result in switching off of LANA.

Although over 60 million years of evolutive divergence amongst the human Kaposi sarcoma herpesvirus and its rodent homologue was seen, the functional mechanisms of LANA remained the same. The study was published in PlosPathogens.

These outcomes allowed the team to create a chimera virus, a mouse virus with a human viral gene. This allowed the testing of molecules which inhibit human LANA protein in mice model of the disease. In addition, the human herpes virus infection, as well as associated cancers, was treated by its use. In future, these molecules are expected to be used as drugs in curing Kaposi virus-associated lymphomas.

Pedro Simas  highlighted, "In addition to Kaposi virus the same experimental strategy to create chimera viruses, previously thought to be theoretically non-viable, can now be used for other viruses that use proteins similar to LANA, such as the Epstein-Barr virus which infects greater than 90% of the world population or the human papillomavirus responsible for cervical cancers."

A chimera virus may treat cancers caused by human herpes virus infection.