A liquid cartilage extract as an adjuvant to conventional treatment for the maintenance of a healthy angiogenic balance as well as the support of healthy hematocrit level and red blood cell count

Townsend Letter for Doctors and Patients,  July, 2005  by Dominique R. Garrel

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A New Perspective on Cancer

The way we think of a disease has profound implications in terms of its treatment. The concept of cancer as a monolithic terminal illness raised the hope of "winning the war on cancer." This idea has led to the development of successive generations of weapons used at their maximum tolerated dose. While the strategy appears useful in prolonging survival, complete remission remains a rare event. This is because even if only one single enemy is spared, it can still raise an army of new, now resistant, cancer cells that can strike again in a fatal breaking wave.

As the long hoped for idea of a universal cure for cancer fades away, a new vision of multidisciplinary complementary approaches emerges and opens the door to mixed protocols that combine alternative therapies with more conventional cancer treatments.

Conventional Cancer Therapies

Cancer treatment is traditionally based on the triad of surgery, radiotherapy and chemotherapy. New approaches, such as antiangiogenic therapy, are also being developed. Each modality comes with its own subset of strengths and limitations.

Surgery

Surgery, in the form of biopsy, is commonly used for cancer diagnosis and staging of tumors. Surgery serves therapeutic purposes as well and has found applications for localized accessible tumors. An early stage primary tumor or a resectable secondary tumor can be removed in the hopes of eradicating all cancer cells. Even when total resection is not possible, surgery can still be used to reduce the tumor burden prior to systemic or radiation therapy. Surgery is also increasingly used post radiation/chemo in an effort to spare the targeted organ as much as possible. Surgery may be recommended in the context of palliative care for the relief of pain resulting from the compression of normal tissue by a tumor.

However, as with any surgery, there are risks of infection, bleeding, and painful or unsightly scars, as well as anesthesia-related complications (clots, strokes, pneumonia and kidney failure). A surgery side effect of major concern to cancer patients is that the removal of a primary tumor is sometimes associated with early relapse and spreading that is believed to be related to an angiogenic surge. The concomitant removal of inhibitors or the release of growth factor stimulators of angiogenesis can activate dormant distant micrometastasis. This was demonstrated in an animal model of lung metastasis (O'Reilly et al., 1994) and also suggested for a subset of premenopausal node-positive breast cancer patients (Retsky et al., 2004).

Radiotherapy

Radiotherapy--or radiation therapy--can help with both the diagnosis and treatment of cancer, or serve in palliative care for the relief of symptoms. For therapeutic purposes, radiotherapy uses focused beams of ionizing radiation composed of photons (X-rays, gamma rays) or particles (electrons, protons, neutrons) to attack cancer cells. High energy rays break chemical bonds within cells to generate unstable free radicals that can disrupt DNA structures. Cells are most sensitive when in their mitosis phase, making rapidly dividing cancer cells highly vulnerable. The damage caused to their genetic material forces the affected cells to stop replicating and triggers apoptosis (programmed cell death). Radiotherapy is used to treat localized solid tumors, such as cancers of the skin, tongue, larynx, brain, breast, uterine cervix, prostate, or head and neck. For reasons not fully understood, leukemia and lymphoma are also responsive in vivo. Radiotherapy can be used before surgery to shrink tumors or after as adjuvant therapy. Mixed protocols with concomitant chemotherapy are increasingly being developed.

Although better equipped than tumor cells with repair mechanisms, normal cells with a rapid turnover (skin, stomach, intestine, hair and progenitor blood cells in the marrow) also run the risk of being damaged. Skin burns, hyperpigmentation, nausea, vomiting, diarrhea, alopecia, tiredness and anemia are therefore common side effects of radiotherapy. Anemia is a particularly insidious side effect. Since radiotherapy relies on the formation of reactive oxygen species (ROS) for cytotoxicity, the oxygen deprivation that occurs with anemia adversely affects cell radiosensitivity, reducing treatment effectiveness (Kumar, 2000). On the other hand, ROS generation is a known trigger of angiogenesis (Maulik and Das, 2002), a fact that may be linked to the observation that radiotherapy sometimes accelerates metastatic growth (Camphausen et al., 2001). Can we solve this apparent conundrum?

Chemotherapy

Chemotherapy refers to the use of chemical agents (drugs) to treat any disease. In the treatment of cancer, chemotherapy is used either alone or in combination with other therapies to kill or control cancer cells. Unlike surgery and radiotherapy, chemotherapy is a systemic treatment that can reach even disseminated cells. Numerous cancer drugs have been developed over recent years. Standard cancer drugs, taking advantage of the high division rate of cancer cells, work by preventing them from entering or completing cell division, eventually killing cells. Newer drugs are also being developed that try to target specific signalling pathways known to be defective in cancer, in an effort to revert cancer cells to a normal phenotype.