Cancer Chemotherapy and Personalized Medicine
Cancer is a leading cause of mortality worldwide. It is known to promote the harboring of accumulated genetic alterations in normal host cells, which then promote cancerous growth. Cancer chemotherapy attempts to eradicate or functionally disable tumor cells by the use of synthetic and/or natural compounds while preserving normal cells. Chemotherapeutic agents can eliminate tumor cells by direct cytotoxicity, activating host immune response, inhibiting the proliferation processes of tumor cells and inducing apoptosis. They are characterized by significant interindividual variations in pharmacokinetics (i.e. clearance and half-life) and pharmacodynamics (i.e. therapeutic responses and drug toxicities). Such variability primarily is due to multiple genetic factors arising from both tumor and noncancerous cells that lead to alterations in drug metabolism and transport, and/or drug targets (e.g. receptors or signaling transduction proteins). Chemotherapeutic agents typically have a narrow margin of safety, in that the ratio of the dose associated with antitumor efficacy and the dose associated with toxicity is small. These drugs are usually prescribed at a maximum tolerated dose (MTD) in order to achieve maximum cancer cell death; as such toxicity often is unavoidable, since there are frequently only subtle differences in the genome of cancer and normal host cells.
The molecular basis of many pharmacogenetic polymorphisms has now been elucidated, and genetic defects have been found to occur in both coding and noncoding regions that disrupt protein function or abundance. In most cases a handful of mutations account for a large proportion of the population defects. The most common genot...
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... development of genetic tools and genotyping of tumor and patient prior to initiating treatment, antitumor efficacy may be increased with a substantial reduction in toxicity.
Owing to the fact that many polymorphisms are likely to affect the outcomes of anticancer drug therapy, as well as other elements of supportive care, clinical trials must include enough patients to insure statistically significant results 75. Because most cancers are not considered 'cured' until a patient is cancer-free for 5 years from the time of diagnosis, even the best-planned pharmacogenetic clinical studies will take multiple years to yield useful information. As the investment in conducting well-planned clinical trials could easily exceed the investment required for genotyping, the public would benefit from incorporation of pharmacogenetic objectives into all cancer clinical trials.
The concept of tumor heterogeneity being related to the course of the disease and clinical outcome in cancer patients draws additional attention in the era of personalized medicine (1). Current cancer treatment strategies are based on the site of origin of the primary tumor. However, it was shown that tumors developed from distinct cell types differ in their prognosis and response to cytotoxic therapies (2...
...rtant that tests are designed to address the issue. Examples of CYP2D6 assays available are the AmpliChip, the Luminex, and AutoGenomics. These assays test for common alleles in the population , therefore rare alleles can go unreported. The AmpliChip test uses about 240 probes to screen for 30 different alleles, including all of the ones mentioned above. Similarly, the Luminex array screens for 22 SNPs, representing 17 of the common alleles and the AutoGenomics assay screens for over 20 alleles (Lyon et al., 2012). When prescribing medications, doctors should be aware of an individual’s metabolism type in order to avoid toxicity or inefficient treatment. For instance, in the case of poor and ultra rapid metabolizers, codeine should not be administered. Instead, doctors should consider prescribing another opiate such as morphine, since it bypasses the CYP2D6 pathway.
While both cancer treatment and chemoprevention trials involve agents that can cause side effects in individuals, chemoprevention trials diverge from treatment trials with respect to the unit of potential benefit. In trials of cancer treatment or of “adjuvant therapies” (secondary prevention), subjects either hav...
Due to the human genome project and other genetic research, tests for mutation which cause diseases have been developed. The list of these illnesses include several types of cancer. Doctors have estimated that as many as 3,000 diseases are due to mutations in the genome. These diseases include several types of colon cancer in which three different genetic tests have been already developed. Debates have arisen on whether these tests should be used regularly or not. Questions including the patients= rights of privacy and the possibility of loss of health or life insurance have been argued over in both the media and political arena.
Genetic testing is an area that has had significant advancement over the past few years. Genetic testing can provide important information regarding diagnosis, treatment, and prevention of illness or disease (Mayo Clinic, 2015). There has been progress recently with genetic testing within oncology and it has become an accepted standard of oncologic care (Robson, Storm, Weitzel, Wollins, & Offit, 2010 February 10).
cancer.org. (2014, 03 15). Genetics and Cancer. Retrieved from Genetics and Cancer | American Cancer Society: http://www.cancer.org/cancer/cancercauses/geneticsandcancer/index
Cancer. The word by itself can conjure images of severely ill and frail people attached to IV medications and chemotherapy drugs as they cling to life in a hospital bed. Other illustrations and pictures depict unrecognizable, misshaped organs affected by abnormal cells that grow out of control, spread, and invade other parts of the body. Cancer studies show that close to one-half of all men and one-third of all women in the United States will be diagnosed with cancer during their lives. Today, millions of people are living with cancer or have had cancer. As patients are newly diagnosed with their specific type of cancer, whether it be breast, lung, prostate, skin, or blood cancer, etc., each patient has to consider what will happen with their future health care plan and who will be involved in their long journey from treatment to recovery. Once diagnosed, cancer patients become the focal point and the center of all activity in terms of care but cancer not only physically invades the patient’s body and well-being, it goes beyond the patient and significantly affects the emotional stability and support from from their loved ones and caregivers. Based on the insidious nature of cancer and typically late detection of malignant diseases, family members (either spouses, children, parents, other relatives, and friends) often become the patient's main caregiver. These caregivers, also known as informal caregivers, provide the cancer patient with the majority of the support outside of the medical facility or hospital environment and become the primary person to provide various types of assistance. They provide the physical support with bathing and assisting in activities of daily living, they become emotional ...
Cancer has become the one of the most feared things for human beings. The various type of cancer have been discovered and there are still a lot of it that undiscoverable. Cancer is a complex disease that have a group of disease. The cancer itself cannot be describe by words. The causes of this cancer is still not being able to be discovered fully. There are only minor factor that can lead to this disease. The carcinogens are believed to be one of the causes that lead to cancer such as asbestos, radon gas, tobacco, PVC and much more from our chemical industries. The environment especially near to the industrial that produce chemical waste can be one of the causes lead to cancer. Cancer also have relation with our age, lifestyle, and diet and also can be genetically inherited. It is believed that older people have higher tendency to get cancer than younger people. Our lifestyle and diet also plays a role causing a cancer by our daily life routine. Smoking tobacco and eating unconsciously (still in research) can also increase the possibility to get cancer especially lung cancer that cause by smoking tobacco. There are several cases, cancer were inherited from their parents. Various type of viruses such as HIV, HPV, EBV and many more virus has a high capabilities to increase the chance a patient to get a cancer because these viruses lower their body immunity to disease.
Cancer is a deadly disease that affects millions of American families each year. In cancer, cell division isn't controlled. Usually, cells have to go through a set of checks and balances before they divide, in cancer that is nonexistent. The cells just keep duplicating until they eventually form disorganized clumps called tumors. Tumors can either be, benign, meaning that they do not possess the power to metastasize to surrounding areas. If a tumor has the power to metastasize, it is classified as a malignant tumor. In simple terms, a benign tumor is not cancerous, and a malignant tumor is. Cancer cells cannot perform the necessary functions they were created for. Some types of cancers, like pancreatic cancer, cannot be cured. Other cancers such as melanoma and breast cancer have high survival rates when caught early. The four major types of treatments used to treat cancer include, surgery to remove the affected organ, radiation, chemotherapy, or biological treatments.
Race is often used as a predictor for a person’s likelihood to get a disease and the effectiveness of medical treatments. The prevalence of certain diseases is different among populations. There are now opportunities for scientists and physicians to tailor medication to specific groups based on specific genetic variants revealed by genetic tests. This new genomic information is being interpreted based on social labels such as ‘race’ and ‘ethnicity.’ Using race as a determinant of a person’s likelihood to get a disease and as a way to create ‘racialized drugs,’ that are designed for people of a certain race, has some benefits but can be potentially harmful. Some groups are more likely to develop certain diseases than others but a person’s risk for common diseases is determined by an unknown pattern of genetic variants, environmental factors, lifestyle characteristics and some random processes (Rotimi, 2004).
The American Cancer Society publishes current advances made in cancer research on their website. Many of the exciting discoveries about how best to treat the disease focus on the genetic aspects associated with certain types of cancer. In addition, treatments aimed at genetic solutions to cancer may be more effective and may cause fewer adverse side effects than traditional cancer treatments (American Can...
Cancer has become a very common illness world wide for any age but mostly affecting adults. One can get cancer from different places in the body that is why there are so many people with cancer, because of all the different types. Cancer can affect any gender, female or male, and any age. It varies from ovarian cancer to prostate cancer, skin cancer to lukemia. Cancer has been a problem for many years yet we have not found a cure to treat and prevent cancer. If one is affected by cancer there are treatments to help take away this illness affecting their body. This essay is about a specific type of treatment for cancer, radiation therapy. There are different types of forms of particles for radiation, for example, protons and waves like x-rays and visible light. These types of radiations are grouped on how much energy they contain because it can cause different affects. A low type of energy radiation can be radio waves and heat, also known as non-ionizing radiation. Ionizing radiation has enough energy to break chemical bonds and knock electrons out of atoms, some examples of these are x-rays and ultraviolet light rays from the sun. That is why radiation is a way to treat cancer because of the strong energy it has to destroy a cancer cell, actually any cell in the body. That’s the issue with radiation therapy, is it worth the damage? It can damage any cell, wether it is healthy or cancerous, which can cause a major affect in the body later on. Although it sounds scary there are other types of treatments such as chemotherapy, targeted therapy, immunotherapy, photodynamic therapy, etc. So if radiation therapy does not sound like the best there are always other options but they do not develop the same results for radiation therapy. Rad...
Genetics & Personalized Medicine. (2013). University of Ottawa Heart Institute. Retrieved on February 3, 2014 from: http://www.ottawaheart.ca/research_discovery/genetics-personalized-medicine.htm
Chinese Americans exhibit an altered response to most drugs manufactured in the United States due to their broad genetic variation from other ethnic groups. Most clinicians are increasingly aware of this trend (Lee, Graeme Fincke, & Ren, 2001). However, the fast increasing nature of the genetic variants used in drug metabolism affects the metabolizing enzymes, which impacts the therapeutic index of any given drug. The changes as mentioned earlier, may result in alterations in the drug
What exactly is Chemotherapy and why would it also kill “good” cells? Cancer could be described as the disease that sends cells out of control, rapidly multiplying the cells, until it harms the body. Chemotherapy is an effective drug treatment intended to treat individuals with various forms of cancer. Generally, this type of treatment is nonspecific, and non-molecular that uses chemical agents to break down all dividing cells. Chemotherapy, or chemo for short, destroys cancer cells, and can also cease the reproduction or spreading of these cells. Despite having apparent benefits, this type of treatment comes at a cost, presenting several disadvantages and side effects. Chemotherapy comes with a heavy burden, nausea and vomiting, diarrhea, anemia, infections, and fatigue is a few of the short-term side effects. This analysis examines chemotherapy as a type of cancer treatment, as well as evaluating complimentary and alternative medicines.