Herpes virus shows potential to kill cancer, page 1

This is really good news, especially after the development of the new HPV vaccine. Since it appears to be in the trial stage it may be awhile before it is applicable to the average person. Just to clear up a few things about Herpes and it applications/use to combat cancer…

There are essentially two strains of Herpes that we currently know of: Herpes Simplex 1 (HSV-1), and Herpes Simplex 2 (HSV-2). There are, however, variations of the Herpes Virus that although not classified strictly as Herpes are found in the Herpesviridae family like Herpes Human Virus 3 (Varicella Zoster Virus- Chickenpox), and others such as Measels and Mumps. All of these virsuses are directly related to the Herpes virus but are sub-categorized by Family and Genus, so officially none of them are what are deemed to be “Herpes” as in the common definition of the word. Herpes behaves in much the same way as other parasitic sexually transmitted diseases in that it has been known to cause more severe conditions as a secondary infections. In fact, because the body has not been given enough time to build up a sufficient immune response, HSV has been known to lead to Meningitis and Encephalitis in adults, and in many cases of neonatal transmission it has been linked to severe brain damage.

HSV (both Simplex 1 and 2) bind to specific Glycoprotein receptors on the cells surface in a way that can be compared to the entry of HIV in a host cell. Once the viral DNA is transferred inside the cell nucleus via the cellular cytoplasm the virus enters a latent period before the process of replication can begin using Thymidine kinase, a specific enzyme key to the function of DNA synthesis and part of the process to introduce deoxythymidine into DNA (this differentiates from HIV infection and some other STD’s because RNA is primarily stored in the viral envelope and injected into the cell to recombinate with the cells own DNA). This latent period dictates exactly why Herpes is able to regenerate and replicate at specific intervals and why it is common to have periods of visible infection. Interestingly enough, both Herpes viruses actively seeks out and attacks neurons (in comparison HIV attacks CD4+ lymphoctye immune cells, and most other STD’s like Hepatitis also attack the immune systems cellular defence mechanism) and another form of the virus known as HSV1716 also has potential applications as a treatment for skin cancer. Skin cells called Melanocytes, in particular, are derived from the same source of original cells that most cells of the nervous system are during fetal development. Both HSV1716 and NV1020 lack a gene called ICP34.5 that normally directs them to prevent early cellular death, and instead are only allowed to replicate inside specific tumor cells that do not need the original gene that was removed from the virus. This way, the virus lacks the potential to destroy healthy cells (because it lacks the gene) but is allowed to kill tumor cells that do not depend on the gene. On this note I have to interject that this is a novel way to treat cancer cells, and if during clinical trials this proves effective I believe it could revolutionize cancer therapy and treatment methods.

The article specifically said that the specific strain of Herpes being investigated for its use in cancer treatment is NV1020, which is commonly cultured from HSV-1 (typically causing cold sores and oral problems), HSV-2 causes Genital lesions and blisters as a side note. Oncolytic Herpes Virus’ such as NV1020 have been previously known to eliminate cancer cells and preserve other non-malignant cells and I figured it would only be a matter of time before their use in cancer research. I would however like to hear if there has been further research done to see if they can eliminate the risk should any of the test subjects have children. Due to the high rate of infection during childbirth, and the fact that these trials are relatively new I think it would be well worth investigating this possibility as NV1020 is only an altered and weakened form of HSV-1, and this does pose a certain risk in itself. Also, although it has not been found to trigger the expression of current Herpes infections in test subjects, I do believe that further research on this as well would be pertinent to the development of an effective treatment. Having said that, one great aspect of this treatment is that if conditionally replicating vectors (CRV’s) based on herpes simplex virus strains can be introduced into the human species they could effectively treat all different forms of cancer…from Colorectal Metastatic and Squamous Cell Carcinomas that NV1020 would be used to treat, to skin cancer that HSV1716 can treat…and many others.