Tumor Hypoxia and High Dose Chemotherapy
Hypoxia is a medical term that refers to a general low level of oxygen (whether in tissues, organs, cells, or blood, etc.). A good review on one of the reasons chemotherapy doesn’t work very well is an article entitled Tumor hypoxia, chemotherapeutic resistance, and hypoxia-related therapies (in Cancer Treatment Reviews 2003; 29:297-307). The article explains that low tumor oxygenation (anaerobic physiology) is one of the reasons that cancer cells are not killed completely by high dose chemotherapy. Tumors larger than 1mm³ in volume contain regions of hypoxia as a result of the disordered blood vessel structure and increased diffusion distances found in tumors. This topic is discussed in the book my wife and I wrote, Treating Cancer With Insulin Potentiation Therapy. Hypoxia can also be caused by low hemoglobin levels in the blood due to tumor-associated and therapy-induced anemia, which further compromise the oxygen-carrying capacity of the blood.
The article goes on to explain that many chemotherapeutic agents are dependent on cellular oxygenation for maximum efficacy. Cytotoxic alkylating agents, such as the melphalan component of nitrogen mustard, are a class of chemotherapeutic drugs whose action involves transferring alkyl groups to DNA during cell division.
Tumor cells in normoxic (good oxygen) conditions are more sensitive to melphalan, in contrast to their hypoxic counterparts. Two other common chemotherapeutic agents, etoposide and bleomycin, were also found to be less effective in hypoxic environments.
The article explains that using Erythropoietin to increase red blood cells could be a way to increase cancer cell oxygenation and help chemotherapy to be more effective.
The authors summarize that while hypoxia was once seen as a mere consequence of cancer, it is now recognized as a highly influential factor that facilitates the survival of tumor cells with growth advantages, and results in an aggressive tumor phenotype. They also conclude that hypoxia hinders chemotherapeutic treatment by promoting tumor cell resistance to conventional drugs. Hypoxia, therefore, is a prime target for the development of novel cancer therapeutics.
As a result of these investigations and our increased understanding of the causes and effects of tumor hypoxia, treatment doses will be lower, and the benefits will be greater for our cancer patients. Optimizing therapies based on the differential hypoxia between tumor and normal tissues, and the ability to increase oxygenation of tumors, will revolutionize contemporary cancer treatment.
Supplements Cannot Cure Cancer!
About every month or so, some newscaster or reporter will tell of a new compound, food or food group, genetic finding, or supplement (vitamin, mineral, or nutritional) that decreases one's cancer risk. These findings are great and play a role in natural medicine care, especially if someone who has a high cancer risk is trying to prevent cancer. There is nothing better than preventing cancer from forming, but cancer prevention is not cancer treatment.
Supplement Use For Prostate Cancer
A patient came in with all of his supplements. He had lycopene supplements, modified citrus pectin, Echinacea, selenium, saw palmetto, and a host of others. Any supplement that he read about that supposedly helped the prostate gland he bought and used. He must have been taking 200 pills a day from about 20 different bottles. He was also eating healthy foods and drinking distilled water. His PSAs (prostate-specific antigens) were not climbing quickly, but they were going up and hovering at about 28. A biopsy confirmed prostate cancer.
The patient was slowing the progression of his disease, but it was still progressing. Most of the items that he was taking were great for prostate health, but they were not likely to give him tumor remission, which was the ultimate goal. I explained the possibilities with natural medicine, surgery, and the differences in nutritional supplements.
He underwent a comprehensive prostate cancer profile that looked at various hormone levels. We agreed that he needed to get his dihydrotestosterone levels down, which was one of the factors involved in feeding his cancer. He was started on a nutritional supplement for this. I also felt that he may have some heavy metal toxicity that might be related to his cancer, but he chose to just go ahead with prostate removal. He has done well and remains cancer free. He continues to take his nutritional supplements and eat a healthy diet.
The patient had read a lot about prostate cancer prevention and felt that he must take gobs of selenium. Well, that is great if you want to get selenium poisoning. Selenium is a good mineral for a cancer patient to take, but what is the goal of therapy? If it is tumor regression, a cancer patient then needs to be under the care of a physician. Just because a vitamin, mineral, or nutritional product has some cancer prevention properties does not mean that it will cause a tumor to shrink. One can almost assume the opposite; it will be great for tumor prevention but not nearly strong enough for tumor regression. This is why when picking an appropriate cancer treatment or therapy, or even a supplement for that matter, it is important to know what its purpose is. Taking a little selenium is fine if you have prostate cancer; just don't put your hopes into it shrinking your tumor.
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