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| What is Cancer? |
 The word cancer (first used by Hippocrates) comes from karcinos(carcinos), the Greek word for the crustacean-the crab. Hippocrates used this word to describe the ailment because the tentacle projections (of cancer afflicted cells) immediately called to mind its similarity to the form of a crab.
Cancer is characterized by an uncontrolled division of the cells that can be expressed as a solid tumor, also called as malignant tumor (e.g. breast cancer) or just an excessive multiplication of cells without the formation of a tumor (e.g. blood cell cancer). |
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| Development of cancer: Carcinogenesis. |
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The substance that causes cancer is termed as a carcinogen. Carcinogens damage the genetic material (DNA) of cells and convert a normal cell into a cancerous cell. This process of transformation, from a normal cell to a cancerous cell, is called as carcinogenesis.
Carcinogens are responsible for the production of cancer cells. Once produced, the rapid multiplication or proliferation of cancerous cells is what results in an invasion of the tumor on the surrounding tissue. This starts a fight between the normal and malignant (cancerous) cells for space and nutrition. Victory of the malignant cells, in this battle, leads to the destruction of adjacent organs and gradually, the size of the tumor increases.
Some cancerous cells detach from the tumor and enter the blood and lymphatic circulation. As soon as they find a suitable site, they anchor themselves in that organ and develop a new tumor known as a secondary tumor or metastasis. This is how cancer spreads from one organ to other.
All cells have a definite life span. They undergo apoptosis when their life span is complete (apoptosis is a term used to define 'programmed cell death'). Some cancer cells loose this program and thus live indefinitely. |
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| Carcinogenic factors |
Cancers produced |
| Tobacco in all its forms (e.g. smoking, chewing etc.) |
Oral cancer, Lung cancer, Kidney cancer, Esophagus cancer, Bladder cancer |
| Alcohol |
Liver cancer.Also,alcohol increases the penetration of other carcinogens in the cells |
| Ultraviolet Radiations from sun rays |
Skin cancer |
| X-ray radiations |
Lung cancer, Blood cancer, Skin cancer |
| Obesity |
Breast and Colon cancer |
| Drugs |
Stomach cancer, Breast cancer |
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| It is a serious situation! |
| The gravity of this fatal disease is more than can be imagined. Let's take a look at the statements (specific to India) published by various study groups to help us understand better its menacing magnitude - |
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 One in 12 women in urban India will develop cancer in herlifetime.
One in every 10 cancer deaths worldwide is in urban India. What's more alarming is that 75-80% of cancer patients are in the advanced stages of the disease at the time of diagnosis.
India has the highest rate of cervical cancer in the world.
Over the next 10 years 8% deaths in India will be due to cancer. |
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| Cancer and oxidative stress |
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To understand the role of oxidative stress in cancer it is essential to know about certain elements called as the free radicals.
An atom has protons and neutrons at its center and electrons revolving around the center in orbits. In normal conditions, these electrons are found in pairs. If an electron revolving around the center is not paired, the species is called as a free radical. These free radicals are unstable and highly reactive. To achieve stability they 'rob' electrons from the surrounding molecules to produce an electron pair. Due to this, the molecule from which the electron is removed becomes unstable and turns into a free radical. This process of 'robbing' repeats with the new free radical and the chain progresses. In this way, a single radical is capable of producing a sequence of electron transfer reactions.
The process of the removal of electron is called as oxidation. And the stress thus generated by the free radicals is called as oxidative stress.
These free radicals attack fatty acids and proteins in cell membranes and cause damage to it. Free radicals also damage theDNA.
Free radicals and oxidative stress play a crucial role in thedevelopment of cancer. Exposure to various environmental factors, including tobacco smoke and radiation leads to the formation of free radicals. Over time, such damage may become irreversible and even lead to cancer. Studies have found that cancer cells are persistently exposed to more oxidative stress than adjacent normal tissue. It has been seen that cancer-related oxidative stress plays a key role in the progression and outcome of cancer.
The interference of oxidative stress in cancer even extends to the treatment. Chemotherapy is the most common treatment of cancer, which makes use of drugs and radiotherapy is the treatment of cancer with the help of radiations. Both radio and chemotherapy treatments induce additional oxidative threat by increasing radical oxygen speciesand escalating the stress on cancer patients. |
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| Oxidative stress plays a crucial role in the development and treatment of cancer |
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| Antioxidants and Cancer |
| Antioxidants are substances whose presence, in relatively low concentrations, significantly inhibits the rate of oxidation. It is the counter to the process of oxidation. Antioxidants deal with these free radicals and control oxidative stress. Every cancer patient is exposed to oxidative stress due to an excessive burden of free radicals, which are produced either by the disease or by the treatment. To neutralize this oxidative stress our body has a store of natural antioxidants present in
the form of various secretions such as Albumin, Bilirubin, Estrogen, etc. These are the Natural (physiological) antioxidants that our body uses to fight off the threat posed by oxidative stress. These natural antioxidants, which are synthesized in our bodies, may not always be sufficient to take care of the additional burden of free radicals generated in cancer. So, we need to extract antioxidants from our diet. The advantages of dietary antioxidants in cancer have been proven through extensive research. Also, a great deal of evidence indicates that diets rich in fruits and vegetables are associated with a lower risk of incurring a number of common cancers, particularly those of the lung, oral cavity, pharynx,larynx, and cervix. |
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| Cancer patients need a supplementary intake of antioxidants |
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 We can get a large amount of antioxidants from our food. But, our supposedly “modern”, and devious ly unhealthy, food habits prevent the sufficient intake of these m u c h - n e e d e d d i e t a r y antioxidants. This is the reason why we need additional supply of antioxidants. Various herbal antioxidants present in nature have the potential to offer a range of advantages in cancer.
Following information cites the evidence of medicinal advantages ofsome herbal antioxidants in cancer. |
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| Herbal antioxidants induce apoptosis |
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 We know that apoptosis is a process by which normal cells undergo spontaneous di s int egr a t ion or de a th (programmed cell death). Some cancer cells loose this program and thus can live indefinitely. Herbal antioxidants like Grape Seed extract, Goji Berry, Noni and Mangosteen induce apoptosis of these cells and promote the death of cancer cells.1,2,3,4 |
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| Herbal antioxidants inhibit multiplication of cancer cells |
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| Multiplication of cancer cells plays a crucial role in the development and reach of the disease. Herbal antioxidants like Grape Seed extract, Green Tea, Goji Berry and Mangosteen prevent multiplication or proliferation of the cancer cells and thus control the 5,6,7,8 growth of the disease. This property of these antioxidants is called as the anti-proliferative effect. |
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| Herbal antioxidants inhibit blood supply to the tumor |
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| Like normal cells, cancer cells also require nutrition for their growth. They grab this nutrition from the blood vessels that supply blood to the tumor. Grape Seed extract and Noni fruit inhibit the growth of blood vessels supplying to the tumor and thus reduce tumor growth 9,10 |
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| Herbal antioxidants kill cancer cells |
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Grape Seed extract shows great potential in the destruction of cancer cells. This action is termed as the cytotoxic activity. Cytotoxic effects of the Grape Seed extract have been successfully demonstrated in studies of cancer cells from the human breast, lung and stomach.
In certain cancers the results of chemotherapy are not very convincing. Cancer of the liver is one of such cases. The treatment of liver cancer with chemotherapy has generally been disappointing and there is a deep felt need for more effective and newer drugs. Garcinone E, an active ingredient in Mangosteen, has successfully displayed a 12 powerful cytotoxic effect (the killing of cells) on these cancer cells. A similar effect was observed on stomach and lung cancer cells. |
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| Herbal antioxidants improve defense of body against cancer cells |
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| Interlukins are the substances that are secreted by the immune system (defense system) that are capable of destroying cancerous tumors. Aloe Vera, Noni Fruit and Goji Berry have been shown to improve the functioning of interlukins and thus enhance the tumor-destroying activity of the body. 13,14,15 |
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| Herbal antioxidants support treatment of cancer |
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| We know that both radio and chemotherapy induce oxidative stress by increasing radical oxygen species. Both of these therapies are associated with serious side effects. Research indicates that antioxidants can be beneficial in the treatment of cancer, either as sole agents or as adjuncts to standard radiation and chemotherapy protocols. Antioxidants have been found to both prolong survival and reduce some of the adverse events (side effects) associated with chemotherapy. Grape Seed extract, Noni Fruit and Green Tea, if administered along with anti-cancer agents, can improve the efficacy of these agents and reduce toxicity. Goji Berry may improve recovery of the immunefunction during and after chemotherapy and radiotherapy. .16,17,18,19,20,21,22 |
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| Summary |
In Cancer, Herbal antioxidants :
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| Induce programmed death cancer cells (apoptosis). |
| Inhibit multiplication of cancer cells. |
| Inhibit blood supply to the tumor. |
| Kill cancer cells. |
| Improve defense of body against cancer cells. |
| Lend valuable support in cancer chemotherapy and radiotherapy. |
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Refernces
Int J Cancer. 2004 Feb 20; 108(5): 733-40.
J Ethnopharmacol. 2004 Jan 90(1): 161-6.
Life Sci. 2005 Mar 18, 76(18): 2115-24.
Angiogenesis. 2003, 6(2), 143-9.
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Toxicology. 2000 Aug 7; 148(2-3): 187-97.
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Zhong Yao Cai. 2001 May 24(5): 350-3.
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Breast Cancer Res Treat. 2004 May; 85(1): 1-12
Res Commun. Mol. Pathol. Pharmacol. 2000, 107:137-66.
Med Res Rev. Jul1997 17(4), 327-65.
Proc West Pharmacol Soc 1994; 37: 145-6
Cancer Biother Radiopharm. 2005 Apr 20(2), 155-62. |
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