What is cancer
Cancer is a group of many related diseases that begin in the cells of the body, the basic unit of life. In short, it’s the uncontrolled growth of cells that are derived from normal cells, and it can go on to kill off normal cells either at the original site or in other parts of the body. To understand cancer, it’s helpful to know what happens when normal cells become cancerous.
A tumor can be benign or malignant. A benign tumor is not cancerous. It can often be removed and, in most cases, does not come back. Moreover, the cells from a benign tumor do not spread to other parts of the body. Most important, a benign tumor is rarely a threat to life. A malignant tumor is cancerous. The cells in this type of tumor are abnormal and divide without control or order. They can invade and damage nearby tissues and organs. Also, cancer cells can break away from a malignant tumor and enter the bloodstream or the lymphatic system. That’s how cancer spreads from the original cancer site to form new tumors in other organs; this process is called metastasis. Leukemia and lymphoma are examples of cancers that arise in blood-forming cells.
What causes cancer
The more we can learn about what causes cancer, the more likely we will find ways to prevent it. In the laboratory, scientists explore the possible causes of cancer and try to determine exactly what happens in cells when they become cancerous. Researchers also study patterns of cancer in the population to look for risk factors, or conditions that increase the chance that cancer might occur. In addition, researchers look for protective factors, or things that decrease the risk.
So, how does cancer develop? It develops over time as the result of a complex mix of factors related to lifestyle, heredity, and environment. Even so, a number of factors have been identified that increase a person’s chance of developing cancer. (We will discuss these in detail in the next section.) For instance, many types of cancer are related to the use of tobacco, to what people eat and drink, to exposure to ultraviolet (UV) radiation from the sun, and to a lesser extent, exposure to cancer-causing agents (or carcinogens) in the environment and the workplace. Some people are more sensitive than others to these factors, yet most of the people who get cancer have none of the known risk factors. In addition, most people who do have risk factors do not get the disease.
Cancer risk factors
Smoking tobacco, using smokeless tobacco, and being regularly exposed to environmental tobacco smoke are responsible for one-third of all cancer deaths in the United States each year. This makes tobacco use the most preventable cause of death in the country.
Cigarette smokers are also more likely than nonsmokers to develop several other types of cancer, including oral cancer and cancers of the larynx, esophagus, pancreas, bladder, kidney, and cervix. Smoking may also increase the likelihood of developing cancers of the stomach, liver, prostate, colon, and rectum. People who smoke cigars and pipes are at risk for cancers of the oral cavity about as much as people who smoke cigarettes. Cigar smokers also have an increased chance of developing cancers of the lung, larynx, esophagus, and pancreas. When a smoker quits, however, the risk of cancer soon begins to decrease and continues to decline gradually each year.
What is the role of diet in the development of cancer? Some evidence suggests a link between a high-fat diet and certain cancers, such as cancers of the colon, uterus, and prostate. Being seriously overweight may be linked to breast cancer among older women and to cancers of the prostate, pancreas, uterus, colon, and ovary in the general population. Other studies suggest that eating foods containing fiber and certain nutrients may help protect against some types of cancer.
We may be able to reduce our cancer risk by making healthy food choices. A well-balanced diet includes generous amounts of foods that are high in fiber, vitamins, and minerals and low in fat. This means eating a lot of fruits and vegetables and more whole-grain breads and cereals every day, along with fewer eggs and not as much high-fat meat, dairy products (such as whole milk, butter, and most cheeses), and oils (such as salad dressing, margarine, and cooking oil).
Ultraviolet (UV) Radiation
UV radiation from the sun causes premature aging of the skin and skin damage that can lead to skin cancer. Artificial sources of UV radiation, such as sunlamps and tanning booths, also can cause skin damage and probably increase the risk of getting skin cancer.
To help reduce the risk of skin cancer caused by UV radiation, it’s best to reduce exposure to the midday sun (from 10 A.M. to 3 P.M.). Many doctors believe that, in addition to avoiding the sun and wearing protective clothing, wearing sunscreen especially one that reflects, absorbs, and/or scatters the two main types of UV radiation (UVA and UVB)—may help prevent some forms of skin cancer. Sunscreens are rated in strength according to a sun protection factor, or SPE. The higher the SPF, the more sunburn protection that’s provided. Sunscreens with SPFs of 12 through 29 are adequate for most people, when applied according to the directions. Typically, those directions recommend to apply sunscreen liberally and to reapply it after going in the water.
Heavy drinkers have an increased risk of cancers of the mouth, throat, esophagus, larynx, and liver. People who smoke cigarettes and drink heavily are at especially high risk for these cancers. Some studies suggest that even moderate drinking may cause a slight increase in the risk of breast cancer.
Cells may be damaged by ionizing radiation from X-ray procedures, radioactive substances, rays that enter the earth’s atmosphere from outer space, and other sources. In very high doses, ionizing radiation may cause cancer and other diseases. Studies of people who survived the dropping of atomic bombs in Japan during World War II show that ionizing radiation increases the risk of developing leukemia and cancers of the breast, thyroid, lung, stomach, and other organs.
Before 1950, X-rays were used to treat noncancerous conditions (such as an enlarged thymus, enlarged tonsils and adenoids, ringworm of the scalp, and acne) in children and young adults. Those who received radiation therapy to the head and neck have a higher-than-average risk of developing thyroid cancer. Anyone who has had such a treatment should report it to his or her doctor.
Chemicals and Other Substances
Being exposed to certain chemicals, metals, and pesticides can also increase the risk of cancer. Asbestos, nickel, cadmium, uranium, radon, vinyl chloride, benzidene, and benzene are all examples of well-known carcinogens. Each may act alone or along with another carcinogen, such as cigarette smoke, to increase the risk of cancer. For example, inhaling asbestos fibers at work increases the risk of all lung diseases, including cancer, and for asbestos workers who smoke, that risk is especially high.
It’s important to follow work and safety rules to avoid or minimize contact with dangerous materials. In most cases, employers are required by law to inform workers of the dangers from chemicals and other substances found in their work environment.
Hormone Replacement Therapy (HRT)
Doctors may recommend HRT using either estrogen alone or in combination with progesterone to control the symptoms that may occur in women during menopause (such as hot flashes and vaginal dryness). Studies have shown that the use of estrogen alone increases the risk of cancer of the uterus. Therefore, most doctors prescribe HRT that includes progesterone along with low doses of estrogen. Progesterone counteracts estrogen’s harmful effect on the uterus by preventing overgrowth of the lining of the uterus, which is associated with taking estrogen alone. (Estrogen alone may be prescribed for a woman who has had a hysterectomy, or surgery to remove the uterus, and is therefore not at risk for cancer of the uterus.) Other studies show an increased risk of breast cancer among women who have used estrogen for a long time, and some research suggests that the risk might be higher among those who have used estrogen and progesterone together. HRT has proven and presumable benefits for women who wish to preserve their postmenopausal health, including the prevention of bone loss and age related dementia.
DES is a synthetic form of estrogen that was used starting in the early 1940s and then discontinued in 1971. Some women took DES during pregnancy to prevent certain complications, only to discover years later that doing so put their daughters at risk for certain cancers. DES-exposed daughters have an increased chance of developing abnormal cells (dysplasia) in the cervix and vagina and are also at greater risk for a rare type of vaginal and cervical cancer. A woman whose mother took DES should tell her doctor about her exposure and have pelvic exams done by a doctor familiar with conditions related to DES.
Women who took DES during pregnancy may themselves have a slightly higher risk for developing breast cancer. Again, they should tell their doctors about their exposure. At this time, there does not appear to be an increased risk of breast cancer for daughters who were exposed to DES before birth. However, more studies are needed to follow these daughters as they age and enter the age range when breast cancer is more common.
Does cancer run in families? Certain types of cancer—including melanoma and cancers of the breast, ovary, prostate, and colon—do tend to occur more often in some families than in the rest of the population. It’s often unclear, however, whether a pattern of cancer in a given family is due primarily to heredity, to factors in the family’s environment or lifestyle, or to chance, pure and simple.
Researchers have learned that cancer is caused by changes (called mutations or alterations) in the genes that control the normal growth and death of cells. Most cancer-causing gene mutations are the result of factors in an individual’s lifestyle or environment. However, some are inherited; that is, they are passed from parent to child. Having such an inherited gene alteration does not mean that someone is certain to develop cancer; rather, it means that his or her risk for cancer is increased.
How is cancer treated
Traditionally, a limited number of cancer therapies have been used. The most common are surgery, chemotherapy, and radiation therapy, which may be used separately or in combination, depending on the nature of the diagnosis and the physician making it. Certainly, anyone who has been diagnosed with cancer should explore all the possible treatment options and consult other medical professionals, as well.
Surgery involves removing the cancerous tissue and perhaps some of the surrounding area. It’s often the first line of treatment for cancers involving tumors, such as breast cancer and colon cancer. The basic premise is to cut out the bad tissue and leave the good. The problem is, in many cases, some bad tissue is unintentionally left behind, while in others, too much good tissue is removed. The consequences of removing too much or too little can be devastating and even fatal, depending on the area of the body. In removing a brain tumor, for instance, the room for error is not large. The accuracy of surgery to remove cancerous tissue will continue to improve with advances in both diagnostic and surgical techniques.
Surgery is often followed by another type of treatment in an effort to destroy any remaining cancer cells. One of the most common is chemotherapy, which involves administering a highly toxic drug through a series of treatments that may span a week’s or even a month’s time. The drugs used in chemotherapy, such as 5-flurouricil (5-FU), are thought to be more harmful to the cancer cells than to the other cells of the body. These drugs act at the level of DNA, causing it to malfunction and thus preventing the cells from dividing. This is critical to stopping the spread of cancer, since cancerous cells multiply in an uncontrolled manner.
However, chemotherapy has some drawbacks. Common side-effects of chemotherapy include severe nausea, loss of healthy cells, and hair loss. In addition, the success rate of chemotherapy depends largely upon what stage the cancer is at. That is, the more advanced the cancer, the less the likelihood that it can be treated successfully.
The third major cancer therapy is radiotherapy (or radiation therapy), in which a source of radiation is directed to the site of the cancer either with a stream or by a carrier molecule (often a protein called an antibody). Like chemotherapy, radiotherapy often follows surgery as a second line of defense. And again, more than one treatment may be needed across a timeframe of weeks or months, depending on the nature of the cancer. In some cases, treatment may be extended or restarted to deal with a possible recurrence of the cancer.
Radiotherapy isn’t 100 percent effective in killing the cancerous cells. Plus, a common side-effect of radiotherapy is that good tissue is damaged, perhaps leading to future illness. As mentioned earlier, before having radiotherapy, a patient should talk with his or her doctor about the side-effects of radiation treatment, which may include increasing the risk of getting a second cancer.
A relatively new mode of cancer treatment is laser ablation, which involves blasting the cancer cells with a laser. There are several problems with this method. For instance, it’s likely that not all of the cancer cells will be killed with one treatment, which will mean having to repeat the procedure. It’s also possible that too much tissue will be killed or even that parts of the body will be destroyed. Given the newness of this technology, it’s likely that these problems will lessen with development in laser and computer technology.
What is the probiotic solution
The body has a limited number of cells. If one dies, it’s replaced with an exact copy of itself in the exact location. The whole body works like that. What happens in cancer is that the cells start to grow uncontrollably, which, by it-self, is not bad. The problem is that in addition to growing, they do a number of harmful things: release toxins, disrupt the normal functioning of whatever tissues or organs they happen to be in, and consume a lot of energy.
What causes cancer cells to grow uncontrollably is the mutations that occur at the gene level, and those mutations can occur for several reasons. First, the cells may be attacked by something like a virus, which will attach itself to the normal human cell and then inject its DNA (or genetic material) into the DNA of the normal cell. This can (but does not always) disrupt the normal functioning of the otherwise healthy cell, causing mutation.
Alternatively, the mutations can occur as a result of exposure to mutagenic compounds, which are simply chemicals or substances that cause DNA to change. To understand this, think of each individual cell’s DNA as being made up of four small letters G, A, T, and C that are organized in a precise way, such as GATCCCAAG. A single, small piece of DNA will always look just like that, even after the cell divides. That’s how the DNA (sometimes called the genetic code) is passed on from generation to generation. But if, say, the T is changed to a C by something that causes mutation, then the code will read GACCCCAAG. This tiny change could make the difference in whether that cell lives or dies.
How does a mutation happen? Well, everything a cell does everything is the result of what its DNA says or to use our example, by how the letters are arranged. Certain compounds can actually come in and change those letters. Those compounds are what are collectively referred to as mutagens or carcinogens. (There is a minor difference between the two, but it isn’t relevant to this discussion.)
When DNA is doing its job, the cell is happy and normal. It divides a limited number of times, and given that, it dies at a predetermined time. All normal cells do this. But as part of this normal functioning for instance, in replication/duplication the DNA of the cell has to be “unwrapped,” so to speak. (Most DNA is kept tightly packed for a number of reasons, one of which is that the stuff that does the packing actually protects the DNA from carcinogens.)
This unwrapping increases the chance of a bad compound attacking the DNA. The more often the DNA is unwrapped, the more likely it will be attacked and hurt. How well or how poorly it survives depends directly on the sequence of those four letters, which, in turn, can be affected by toxic, mutagenic, and carcinogenic compounds.
So, where do probiotics come in?, They actually function in a number of ways. First, they can make substances that will interact with the offensive materials and detoxify them. Second, probiotics can actually take in the toxic materials and process them by various pathways, making them less toxic. Third, probiotics can physically keep out bad bacteria. This is good not just because bad bacteria, such as the infamous E. coli (which is often the culprit in cases of contaminated meat), can produce substances that make us feel sick and can even kill us but also because those same bad bacteria can take what would otherwise be innocuous materials and turn them into carcinogens.
Probiotics do this by physically displacing the bad bacteria. Inside the human gut, there is limited space. In order for a bacteria, either good or bad, to exert an effect on the health of the human host, it has to spend a little time hanging out quite literally, in fact. That is, the bacteria must attach itself to the lining of the gastrointestinal (GI) tract in a process called bacteria adherence. Certain bacteria occupy certain areas of the GI tract. For instance, Lactobacilli tend to inhabit the upper portion, known as the small intestine, and Bifidobacteria tend to inhabit the colon, which is part of the large intestine.
Probiotics normally live and die just like human cells. As they age, they can be mutated so they do not bind as well. When that happens, there is an increased chance that any bad bacteria that are passing by might adhere in place of the probiotics as they start to lose their foothold on the intestinal lining. When the bad bacteria are established where they should not be, they can do a few things—none of them good.
First, these bacteria can chew away at the lining of the intestine. This means that the cells in the lining will have to be replaced, requiring the DNA to be unwrapped and thus increasing the chances of mutagenesis. Second, the bad bacteria can produce toxic compounds that will destroy the good bacteria and the human cells. Again, the human cells will try to replace themselves and have to divide again. (Clearly, because cells only have a limited number of lives, it’s not good for them to have to replace themselves constantly.)
Third, the bad bacteria can take potentially noxious substances and make them very carcinogenic. Those carcinogens will then go on to wreak havoc in the normal cells as they try to go about their lives. Actually, the bad bacteria also do something the good bacteria do, but they do it in the opposite way. Both good and bad bacteria condition their environment; for instance, they can alter things such as the pH by secreting or not secreting acids. They can also produce bactericidal compounds that will kill off the opposite type of bacteria, good or bad. So, when the bad bacteria do this, there will be more and more bad guys around, causing trouble.
One solution to this problem is to add more good bacteria, which can be done by supplementing with probiotics. This might not be as simple as it sounds, as there are over 400 species (or types) of probiotics in the normal GI tract. To help sort things out, a number of companies have come up with what they believe are the most predominant bacteria normally found in healthy people. Typically, the list includes 10 to 20 different probiotics.
While research on probiotics goes back over 100 years, the techniques required to mass produce and test probiotics have only been available for about 20 years. That’s why, in large part, so few types of probiotics are available only a couple dozen strains. The other reason for this scarcity has to do with the marketing of these products. Consider that most companies want to sell you their own wonderful probiotics, and in order to do that, they must show you how many studies have been done on their strains. Having limited amounts of funds available for research, companies focus on certain strains, rather than test all of them individually. The marketing gurus realize that you, the consumer, will be more impressed to see that 100 clinical studies have been done on a specific strain, such as LA-5 or BB-12 (even though they are all amazingly similar), than you will be to see that 100 different studies have been done on 100 different bugs (most of which are not available anyway).
Taking probiotics is not a one-time fix. To be sure, the toxic and potentially toxic compounds and bad bacteria in your body never stop coming. You must keep adding good bacteria to hold off the onslaught of bad bacteria. Also, the good bacteria will be under constant assault, and they can suffer mutations the same way normal cells do.
When that happens, the cells will end up weakened or dead. When the probiotics are weakened or dead, they cannot detoxify the noxious compounds and fend off the bad guys. The result is that the bad guys will eventually win. That’s why you need to continually supplement your diet with new, fresh, viable probiotics. Make sure that fresh troops are constantly on guard, protecting your health.
We have made great strides in understanding cancer in all of its facets and guises. And along with these gains has come an increased survival rate. For instance, melanoma is now almost 100 percent curable, if caught early on. Ongoing research on other types of cancer will hopefully bring more of the same good news. The more we learn about the causes of cancer, the better we will be able to fight it—in fact, the better we will be able to prevent it!