Information On Shark Cartilage
Cartilage, a translucent elastic tissue, composes most of the skeleton of embryonic and very young vertebrates and, through a process of calcification, is transformed into bones which make up the fully developed skeletal system.
Cartilage is also found between the segments of the spine and at the ends of long bones, where it acts as a shock absorber and a bearing surface to reduce the friction between moving parts. It is tough and elastic.
It is a source of mucopolysaccharides which have anti-inflamatory and joint protective properties.
Shark cartilage has gained increased popularity as an unconventional cancer treatment and in prevention of cancer. Shark cartilage was initially promoted by William Lane, Ph.D. in his book "Sharks Don't Get Cancer" and the follow-up book, "Sharks Still Don't Get Cancer." Unfortunately, sharks do get cancer. They develop melanoma, brain tumors, cancer of the blood system and even cancer in the cartilage.
Shark cartilage is purported to contain angiogenesis inhibitors, which prevent the formation of new blood vessels that tumors need to grow. A modest anti-angiogenic effect has been seen in test tubes, but not in humans at this point. Shark cartilage is supplied in powder and capsule forms. It is taken orally and sometimes as an enema.
Cartilage products are widely used in the United States for the treatment of medical conditions such as cancer, arthritis, and psoriasis. It is estimated that more than 50,000 Americans used shark cartilage in 1992, and with media attention increasing, this number is likely to have grown substantially. In 1995 more than 40 brand names of shark cartilage products were being sold in the United States. Most purchases are made over the counter. Use of these products is not limited to humans. Products containing shark and bovine (cattle) cartilage for both human and veterinary use have been marketed and sold throughout the world.
Various types of cartilage, including pig, sheep, chicken, bovine, and shark, have been under scientific investigation for more than 30 years. Studies to test the effectiveness of cartilage as an anti-inflammatory and analgesic (pain reliever) for arthritis and to determine if cartilage can facilitate wound healing in conditions such as psoriasis have been conducted. In vitro (test tube) and in vivo (in a living body) tests were performed on murine (mice and rat) models, and several randomized, double-blind studies were conducted in Europe with osteoarthritis patients. The European studies demonstrated that chondroitin sulfate, an ingredient found in cartilage, improves joint mobility and reduces pain.
During the mid 1970s, several published studies reported that the cartilage, serum, and liver of sharks may have antineoplastic (anticancer) properties against lung cancer and leukemia in a murine model. Research continued during the 1980s. However, many results from these early studies generated additional questions about the possible mechanism(s) of action of these compounds and provided few definitive answers.
The use of shark cartilage as a cancer treatment has drawn attention because of the popular belief that the incidence of cancer in cartilaginous fish (sharks, skates, and rays) is very rare or nonexistent. However, literature on cancer in fish shows this may not be true. Comprehensive lists of literature compiled in 1933, 1948, and 1969 document that a sampling of cartilaginous fish captured over the years were found to have cancer. Although there is no way to establish the prevalence of cancer among all sharks, various types of tumors have been found in cartilaginous fish. The majority of these cancers are melanomas and soft-tissue sarcomas.
Mechanisms of action proposed to explain why cartilage compounds might be useful as a cancer therapy are based on information derived from experiments using animal models and human cell cultures. The most frequently cited is antiangiogenesis, a process that slows or stops the growth of blood vessels that supply nutrients and oxygen to the tumor. Other mechanisms of action include blocking the formation of certain enzymes (metalloproteinases) that tumors use to invade tissue surrounding the tumor and stimulating the immune system. Some researchers have hypothesized that bovine and shark cartilage have different mechanisms of action.
While bovine cartilage reportedly has antiangiogenesis properties, it has also been proposed that the compound inhibits tumor cell growth by using mucopolysaccharides (large sugar molecules) to block cell division. Other proposed mechanisms of action include inhibition of protease (a chemical that can break peptide bonds in cells), blocking the formation of collagenase (enzymes that break down the protein collagen), and the activation of the immune system, primarily by activating macrophage (cells that kill and digest microorganisms) and cytotoxic (tumor-killing) T and B cells.
Data from laboratory studies show that antiangiogenic activity is the mechanism of action most often noted for shark cartilage, although exactly how this activity occurs is still being debated. Research is also being conducted to learn about the antimutagenic activity of shark cartilage (its ability to inactivate or reverse the effects of cancer-causing agents), and whether shark cartilage may protect cells from DNA damage by being a scavenger of free radicals.
Bovine cartilage reportedly was first used to treat a human with cancer in 1972. Since then, results of 3 phase I/II and phase II clinical trials, 4 clinical series, and a best case series on humans using various formulations of cartilage have been reported. Several clinical trials evaluating the effectiveness of bovine and shark cartilage in many types of solid tumors are ongoing or have been completed. These trials include shark cartilage with nutritional support at the Simone Cancer Center in Lawrenceville, New Jersey; a phase II trial of shark cartilage for breast and prostate patients at Metabolic Associates in New Jersey; a bovine cartilage study for renal cell cancer patients at Westchester Medical Center in New York; and a phase II study for breast cancer and brain/spinal tumor patients using a shark cartilage product sponsored by Lane Labs in New Jersey. Preliminary results of these studies are not available at this time.
Antitumor activity of shark and bovine cartilage has been investigated in various cancer cell lines, including astrocytoma, myeloma, ovarian, colon, breast, and Lewis lung carcinoma. Suppression of tumor growth was most pronounced in myeloma cells exposed to continuous, high doses of the compound and in lung cancer cell lines. Limited activity was noted for astrocytoma cells treated with shark cartilage, and for ovarian, breast, and colon cells treated with bovine cartilage. In vivo studies using chicken embryos, mice, and rabbits have also been conducted. Data from cell lines and studies that treat implanted human cancer cells in animals with cartilage indicate some tumor regression or stabilization and/or evidence of angiogenesis inhibition in many cases. The results of 3 studies have been presented at scientific meetings during the past 6 years.
In the first scientific review to be published in a major peer-reviewed journal, researchers have concluded that shark cartilage powder does not demonstrate anti-tumor properties and is not an effective treatment for patients with advanced cancer. More than 50,000 Americans are estimated to have used the powder because of anecdotal claims about its cancer-fighting abilities.
The study, conducted under the auspices of the Cancer Treatment Research Foundation by Dr. Denis R. Miller and his colleagues, examined 60 patients with various advanced cancers who were given three daily doses of shark cartilage for a three-month period - the equivalent time period conventionally used to evaluate other Phase II anticancer agents. Although the shark cartilage was not associated with any serious adverse effects, the study found that none of the patients exhibited any response, complete or partial, to the therapy. Seventy-nine percent of the patients taking shark cartilage experienced tumor progression. However, 21 percent had stable disease with neither progression nor regression of their tumors.
Shark cartilage powder has been recently popularized as a cancer remedy, in part because of preliminary studies showing that certain shark cartilage isolates are "anti-angiogenic" agents - that is, they block the growth of tiny new blood vessels that feed tumors. These isolates (which are the subject of ongoing research) are not the same as the dry, pulverized crude form of shark cartilage that is commonly sold in health food stores and supermarkets, and is promoted through advertisements, books, the media, and websites.
Cartilage, a translucent elastic tissue, composes most of the skeleton of embryonic and very young vertebrates and, through a process of calcification, is transformed into bones which make up the fully developed skeletal system.
Cartilage is also found between the segments of the spine and at the ends of long bones, where it acts as a shock absorber and a bearing surface to reduce the friction between moving parts. It is tough and elastic.
It is a source of mucopolysaccharides which have anti-inflamatory and joint protective properties.
Shark cartilage has gained increased popularity as an unconventional cancer treatment and in prevention of cancer. Shark cartilage was initially promoted by William Lane, Ph.D. in his book "Sharks Don't Get Cancer" and the follow-up book, "Sharks Still Don't Get Cancer." Unfortunately, sharks do get cancer. They develop melanoma, brain tumors, cancer of the blood system and even cancer in the cartilage.
Shark cartilage is purported to contain angiogenesis inhibitors, which prevent the formation of new blood vessels that tumors need to grow. A modest anti-angiogenic effect has been seen in test tubes, but not in humans at this point. Shark cartilage is supplied in powder and capsule forms. It is taken orally and sometimes as an enema.
Cartilage products are widely used in the United States for the treatment of medical conditions such as cancer, arthritis, and psoriasis. It is estimated that more than 50,000 Americans used shark cartilage in 1992, and with media attention increasing, this number is likely to have grown substantially. In 1995 more than 40 brand names of shark cartilage products were being sold in the United States. Most purchases are made over the counter. Use of these products is not limited to humans. Products containing shark and bovine (cattle) cartilage for both human and veterinary use have been marketed and sold throughout the world.
Various types of cartilage, including pig, sheep, chicken, bovine, and shark, have been under scientific investigation for more than 30 years. Studies to test the effectiveness of cartilage as an anti-inflammatory and analgesic (pain reliever) for arthritis and to determine if cartilage can facilitate wound healing in conditions such as psoriasis have been conducted. In vitro (test tube) and in vivo (in a living body) tests were performed on murine (mice and rat) models, and several randomized, double-blind studies were conducted in Europe with osteoarthritis patients. The European studies demonstrated that chondroitin sulfate, an ingredient found in cartilage, improves joint mobility and reduces pain.
During the mid 1970s, several published studies reported that the cartilage, serum, and liver of sharks may have antineoplastic (anticancer) properties against lung cancer and leukemia in a murine model. Research continued during the 1980s. However, many results from these early studies generated additional questions about the possible mechanism(s) of action of these compounds and provided few definitive answers.
The use of shark cartilage as a cancer treatment has drawn attention because of the popular belief that the incidence of cancer in cartilaginous fish (sharks, skates, and rays) is very rare or nonexistent. However, literature on cancer in fish shows this may not be true. Comprehensive lists of literature compiled in 1933, 1948, and 1969 document that a sampling of cartilaginous fish captured over the years were found to have cancer. Although there is no way to establish the prevalence of cancer among all sharks, various types of tumors have been found in cartilaginous fish. The majority of these cancers are melanomas and soft-tissue sarcomas.
Mechanisms of action proposed to explain why cartilage compounds might be useful as a cancer therapy are based on information derived from experiments using animal models and human cell cultures. The most frequently cited is antiangiogenesis, a process that slows or stops the growth of blood vessels that supply nutrients and oxygen to the tumor. Other mechanisms of action include blocking the formation of certain enzymes (metalloproteinases) that tumors use to invade tissue surrounding the tumor and stimulating the immune system. Some researchers have hypothesized that bovine and shark cartilage have different mechanisms of action.
While bovine cartilage reportedly has antiangiogenesis properties, it has also been proposed that the compound inhibits tumor cell growth by using mucopolysaccharides (large sugar molecules) to block cell division. Other proposed mechanisms of action include inhibition of protease (a chemical that can break peptide bonds in cells), blocking the formation of collagenase (enzymes that break down the protein collagen), and the activation of the immune system, primarily by activating macrophage (cells that kill and digest microorganisms) and cytotoxic (tumor-killing) T and B cells.
Data from laboratory studies show that antiangiogenic activity is the mechanism of action most often noted for shark cartilage, although exactly how this activity occurs is still being debated. Research is also being conducted to learn about the antimutagenic activity of shark cartilage (its ability to inactivate or reverse the effects of cancer-causing agents), and whether shark cartilage may protect cells from DNA damage by being a scavenger of free radicals.
Bovine cartilage reportedly was first used to treat a human with cancer in 1972. Since then, results of 3 phase I/II and phase II clinical trials, 4 clinical series, and a best case series on humans using various formulations of cartilage have been reported. Several clinical trials evaluating the effectiveness of bovine and shark cartilage in many types of solid tumors are ongoing or have been completed. These trials include shark cartilage with nutritional support at the Simone Cancer Center in Lawrenceville, New Jersey; a phase II trial of shark cartilage for breast and prostate patients at Metabolic Associates in New Jersey; a bovine cartilage study for renal cell cancer patients at Westchester Medical Center in New York; and a phase II study for breast cancer and brain/spinal tumor patients using a shark cartilage product sponsored by Lane Labs in New Jersey. Preliminary results of these studies are not available at this time.
Antitumor activity of shark and bovine cartilage has been investigated in various cancer cell lines, including astrocytoma, myeloma, ovarian, colon, breast, and Lewis lung carcinoma. Suppression of tumor growth was most pronounced in myeloma cells exposed to continuous, high doses of the compound and in lung cancer cell lines. Limited activity was noted for astrocytoma cells treated with shark cartilage, and for ovarian, breast, and colon cells treated with bovine cartilage. In vivo studies using chicken embryos, mice, and rabbits have also been conducted. Data from cell lines and studies that treat implanted human cancer cells in animals with cartilage indicate some tumor regression or stabilization and/or evidence of angiogenesis inhibition in many cases. The results of 3 studies have been presented at scientific meetings during the past 6 years.
In the first scientific review to be published in a major peer-reviewed journal, researchers have concluded that shark cartilage powder does not demonstrate anti-tumor properties and is not an effective treatment for patients with advanced cancer. More than 50,000 Americans are estimated to have used the powder because of anecdotal claims about its cancer-fighting abilities.
The study, conducted under the auspices of the Cancer Treatment Research Foundation by Dr. Denis R. Miller and his colleagues, examined 60 patients with various advanced cancers who were given three daily doses of shark cartilage for a three-month period - the equivalent time period conventionally used to evaluate other Phase II anticancer agents. Although the shark cartilage was not associated with any serious adverse effects, the study found that none of the patients exhibited any response, complete or partial, to the therapy. Seventy-nine percent of the patients taking shark cartilage experienced tumor progression. However, 21 percent had stable disease with neither progression nor regression of their tumors.
Shark cartilage powder has been recently popularized as a cancer remedy, in part because of preliminary studies showing that certain shark cartilage isolates are "anti-angiogenic" agents - that is, they block the growth of tiny new blood vessels that feed tumors. These isolates (which are the subject of ongoing research) are not the same as the dry, pulverized crude form of shark cartilage that is commonly sold in health food stores and supermarkets, and is promoted through advertisements, books, the media, and websites.
- National Cancer Institute - Cartilage (PDQ?) Complementary/Alternative Medicine
- The American Society of Clinical Oncology - Shark Cartilage Powder Is Ineffective Against Advanced Cancer, Concludes First Scientific Review
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