I did a prior article on cancer, but that was a brief summary. Here, I dare to go deeper, delving more more professionally into the annals of this menacing monster. From the causes, to the cures and more relieving; their cures. Well, this article is not for every one so if you think it interests you, why?..be my guest!
The Many Causes of Cancer
There are about 200 different types of cancer. It can start in any type of body tissue. What affects one body tissue may not affect another. For example, tobacco smoke that you breathe in may help to cause lung cancer. Over exposing your skin to the sun could cause a melanoma on your leg. But the sun won’t give you lung cancer and smoking won’t give you melanoma.
(adsbygoogle = window.adsbygoogle || []).push({});
Apart from infectious diseases, most illnesses (including cancer) are multi factorial. This means that there are many factors involved. In other words, there is no single cause for any one type of cancer.
A. Cancer causing substances (carcinogens):
A carcinogen is something that can help to cause cancer. Tobacco smoke is a powerful carcinogen. But not everyone who smokes gets lung cancer. So there must be other factors at work as well.
B. Age:
Most types of cancer become more common as we get older. This is because the changes that make a cell become cancerous in the first place take a long time to develop. There have to be a number of changes to thegeneswithin a cell before it turns into a cancer cell. These changes can happen by accident when the cell is dividing or they can happen because the cell has been damaged by carcinogens and the damage is then passed on to future cells when that cell divides. The longer we live, the more time there is forgenetic mistakesto happen in our cells.
C. Genetic make up:
There need to be a number ofgenetic mutationswithin a cell before it becomes cancerous. Sometimes a person is born with one of these mutations already. This doesn’t mean they will definitely get cancer. But with one mutation from the start, it makes it more likely statistically that they will develop cancer during their lifetime. Doctors call this genetic predisposition.
The BRCA1 and BRCA2breast cancer genes are examples of genetic predisposition. Women who carry one of these faulty genes have a higher chance of developing breast cancer than women who dThe BRCA genes are good examples for another reason. Most women with breast cancer do not have a mutated BRCA1 or BRCA2 gene. Less than 3 out of 100 breast cancers (3%) are due to these genes. So although women with one of these genes are individually more likely to get breast cancer, most breast cancer is not caused by a high risk inherited gene fault. This is true of other common cancers where some people have a genetic predisposition – for example,colon (large bowel) cancer.
D. The immune system:
People who have problems with their immune systems are more likely to get some types of cancer. This group includes people who have had organ transplants and take drugs to suppress their immune systems to stop organ rejection
*Have HIV or AIDS
*Are born with rare medical syndromes which affect their immunity
*The types of cancers that affect these groups of people fall into 2 overlapping groups
Cancers that are caused by viruses, such as cervical cancer and other cancers of the genital or anal area, some lymphomas,liver cancer and stomach cancer
E. Lymphomas:
Chronic infections or transplanted organs can continually stimulate cells to divide. This continual cell division means that immune cells are more likely to develop genetic faults and develop into lymphomas.
F. Smoking, Body weight, Diet and Physical Activity:
Many cancer cases in the UK are linked to lifestyle factors such as smoking, alcohol, diet, or being overweight. In the western world, many of us eat too much red and processed meat and not enough fresh fruit and vegetables. This type of diet is known to increase the risk of cancer. Drinking alcohol can also increase the risk of developing some types of cancer. There is more information about this on the page aboutdiet causing cancer.
Sometimes foods or food additives are blamed for directly causing cancer and described as carcinogenic. This is often not really true. Sometimes a food is found to contain a substance that can cause cancer but in such small amounts that we could never eat enough of it to do any harm. And some additives may actually protect us. There ismore about food additivesin the page aboutdiet causing cancer.
G. Day to day environment:
By environmental causes we mean what is around you each day that may help to cause cancer. This could include
*Tobacco smoke
*The sun
*Natural and man made radiation
*Work place hazards
*Asbestos
H. Viruses:
Viruses can help to cause some cancers. But this does not mean that these cancers can be caught like an infection. What happens is that the virus can causegenetic changesin cells that make them more likely to become cancerous.
These cancers and viruses are linked
*Cervical cancer, and other cancers of the genital and anal area, and thehuman papilloma virus(HPV)
*Primary liver cancerand the Hepatitis B and C viruses
*Lymphomasand the Epstein-Barr Virus
*T cell leukemia in adults and the Human T cell leukaemia virus
*HPV may also lead to oropharyngeal cancer and non melanoma skin cancers in some people.
Many people can be infected with a cancer causing virus, and never get cancer. The virus only causes cancer in certain situations. Many women get ahigh risk HPV infection, but never develop cervical cancer.
I. Bacterial infection:
Bacterial infections have not been thought of as cancer causing agents in the past. But studies have shown that people who havehelicobacter pylori (H pylori) infection of their stomach develop inflammation of the stomach lining, which increases the risk of stomach cancer. Helicobacter pylori infection can be treated with a combination of antibiotics. Research is also looking at whether substances produced by particular types of bacteria in the digestive system can increase the risk of bowel cancer or stomach lymphomas. Some researchers think that particular bacteria may produce cancer causing substances in some people. But research into this issue is at an early stage.
If bacteria do play a part in causing cancer this could be important in cancer prevention. Bacterial infections can often be cured with antibiotics, so getting rid of the infection could be a way to reduce the risk of these types of cancer.
How is cancer treated?
Cancer treatment depends on the type of cancer, the stage of the cancer (how much it has spread), age, health status, and additional personal characteristics. There is no single treatment for cancer, and patients often receive a combination of therapies and palliative care. Treatments usually fall into one of the following categories: surgery, radiation, chemotherapy, immunotherapy, hormone therapy, or gene therapy.
A. Surgery:
Surgery is the oldest known treatment for cancer. If a cancer has not metastasized, it is possible to completely cure a patient by surgically removing the cancer from the body. This is often seen in the removal of the prostate or a breast or testicle. After the disease has spread, however, it is nearly impossible to remove all of the cancer cells. Surgery may also be instrumental in helping to control symptoms such as bowel obstruction or spinal cord compression.
Innovations continue to be developed to aid the surgical process, such as the iKnife that “sniffs” out cancer. Currently, when a tumor is removed surgeons also take out a “margin” of healthy tissue to make sure no malignant cells are left behind. This usually means keeping the patients under general anesthetic for an extra 30 minutes while tissue samples are tested in the lab for “clear margins”. If there are no clear margins, the surgeon has to go back in and remove more tissue (if possible). Scientists from Imperial College London say the iKnife may remove the need for sending samples to the lab.
B. Radiation:
Radiation treatment, also known as radiotherapy, destroys cancer by focusing high-energy rays on the cancer cells. This causes damage to the molecules that make up the cancer cells and leads them to commit suicide. RaRadiotherapy utilizes high-energy gamma-rays that are emitted from metals such as radium or high-energy x-rays that are created in a special machine. Early radiation treatments caused severe side-effects because the energy beams would damage normal, healthy tissue, but technologies have improved so that beams can be more accurately targeted. Radiotherapy is used as a standalone treatment to shrink a tumor or destroy cancer cells (including those associated with leukemia and lymphoma), and it is also used in combination with other cancer treatments.
C. Chemotherapy:
Chemotherapy utilizes chemicals that interfere with the cell division process – damaging proteins or DNA – so that cancer cells will commit suicide. These treatments target any rapidly dividing cells (not necessarily just cancer cells), but normal cells usually can recover from any chemical-induced damage while cancer cells cannot. Chemotherapy is generally used to treat cancer that has spread or metastasized because the medicines travel throughout the entire body. It is a necessary treatment for some forms of leukemia and lymphoma. Chemotherapy treatment occurs in cycles so the body has time to heal between doses. However, there are still common side effects such as hair loss, nausea, fatigue, and vomiting. Combination therapies often include multiple types of chemotherapy or chemotherapy combined with other treatment options.
D. Immunotherapy:
Immunotherapy aims to get the body’s immune system to fight the tumor. Local immunotherapy injects a treatment into an affected area, for example, to cause inflammation that causes a tumor to shrink. Systemic immunotherapy treats the whole body by administering an agent such as the protein interferon alpha that can shrink tumors. Immunotherapy can also be considered non-specific if it improves cancer-fighting abilities by stimulating the entire immune system, and it can be considered targeted if the treatment specifically tells the immune system to destroy cancer cells.
These therapies are relatively young, but researchers have had success with treatments that introduce antibodies to the body that inhibit the growth of breast cancer cells. Bone marrow transplantation (hematopoetic stem cell transplantation) can also be considered immunotherapy because the donor’s immune cells will often attack the tumor or cancer cells that are present in the host.
E. Hormone therapy:
Several cancers have been linked to some types of hormones, most notably breast and prostate cancer. Hormone therapy is designed to alter hormone production in the body so that cancer cells stop growing or are killed completely. Breast cancer hormone therapies often focus on reducing estrogen levels (a common drug for this is tamoxifen) and prostate cancer hormone therapies often focus on reducing testosterone levels. In addition, some leukemia and lymphoma cases can be treated with the hormone cortisone.
F. Gene therapy:
The goal of gene therapy is to replace damaged genes with ones that work to address a root cause of cancer: damage to DNA. For example, researchers are trying to replace the damaged gene that signals cells to stop dividing (the p53 gene) with a copy of a working gene. Other gene-based therapies focus on further damaging cancer cell DNA to the point where the cell commits suicide. Gene therapy is a very young field and has not yet resulted in any successful treatments.
Using cancer-specific immune system cells to treat cancer
Scientists from the RIKEN Research Centre for Allergy and Immunology in Yokohama, Japan, explained in the journalCell Stem Cell (January 2013 issue) how they managed to make cancer-specific immune system cells from iPSCs (induced pluripotent stem cells) to destroy cancer cells.
The authors added that their study has shown that it is possible to clone versions of the patients’ own cells to enhance their immune system so that cancer cells could be destroyed naturally. These therapies are relatively young, but researchers have had success with treatments that introduce antibodies to the body that inhibit the growth of breast cancer cells. Bone marrow transplantation (hematopoetic stem cell transplantation) can also be considered immunotherapy because the donor’s immune cells will often attack the tumor or cancer cells that are present in the host.
G. Hormone therapy:
Several cancers have been linked to some types of hormones, most notably breast and prostate cancer. Hormone therapy is designed to alter hormone production in the body so that cancer cells stop growing or are killed completely. Breast cancer hormone therapies often focus on reducing estrogen levels (a common drug for this is tamoxifen) and prostate cancer hormone therapies often focus on reducing testosterone levels. In addition, some leukemia and lymphoma cases can be treated with the hormone cortisone.
H. Gene therapy:
The goal of gene therapy is to replace damaged genes with ones that work to address a root cause of cancer: damage to DNA. For example, researchers are trying to replace the damaged gene that signals cells to stop dividing (the p53 gene) with a copy of a working gene. Other gene-based therapies focus on further damaging cancer cell DNA to the point where the cell commits suicide. Gene therapy is a very young field and has not yet resulted in any successful treatments.
Using cancer-specific immune system cells to treat cancer
Scientists from the RIKEN Research Centre for Allergy and Immunology in Yokohama, Japan, explained in the journalCell Stem Cell(January 2013 issue) how they managed to make cancer-specific immune system cells from iPSCs (induced pluripotent stem cells) to destroy cancer cells.
The authors added that their study has shown that it is possible to clone versions of the patients’ own cells to enhance their immune system so that cancer cells could be destroyed naturally.
Hiroshi Kawamoto and team created cancer-specific killer T-lymphocytes from iPSCs. They started off with mature T-lymphocytes which were specific for a type of skin cancer and reprogrammed them into iPSCs with the help of “Yamanaka factors”. The iPSCs eventually turned into fully active, cancer-specific T-lymphocytes – in other words, cells that target and destroy cancer cells.
How can cancer be prevented?
Cancers that are closely linked to certain behaviors are the easiest to prevent. For example, choosing not to smoke tobacco or drink alcohol significantly lower the risk of several types of cancer – most notably lung, throat, mouth, and liver cancer. Even if you are a current tobacco user, quitting can still greatly reduce your chances of getting cancer.
*Skin cancer can be prevented by staying in the shade, protecting yourself with a hat and shirt when in the sun, and using sunscreen. Diet is also an important part of cancer prevention since what we eat has been linked to the disease. Physicians recommend diets that are low in fat and rich in fresh fruits and vegetables and whole grains. Preocessed foods and foods high in saturated fats must be discouraged as much as possible.
*Certain vaccinations have been associated with the prevention of some cancers. For example, many women receive a vaccination for the human papillomavirus because of the virus’s relationship with cervical cancer. Hepatitis B vaccines prevent the hepatitis B virus, which can cause liver cancer.
*Some cancer prevention is based on systematic screening in order to detect small irregularities or tumors as early as possible even if there are no clear symptoms present. Breast self-examination, mammograms, testicular self-examination, and Pap smears are common screening methods for various cancers.
Researchers from Northwestern University Feinberg School of Medicine in Chicago reported in the journal Circulation thatthe 7 steps recommended for protection against heart disease can also reduce the risk of developing cancer. They include:
1. Being physically active.
2. Eating a healthy diet.
3. Controlling cholesterol,
4. Managing blood pressure,
5.Reducing blood sugar and
6.Not smoking