Cancer Treatment & Biotechnology
The First Cancer Treatments
The fight against cancer rages around the globe, with battles taking place at research centers, universities, and in biotech companies. Pharmaceutical companies have made many important advances in suppressing tumor growth and in early detection of cancer using improved testing techniques.
The first treatments for cancer were discovered by scientists studying the effect of mustard gas on soldiers. In 1946, nitrogen mustard was found to shrink lymphomas. Shortly thereafter, a physician named Farber discovered that leukemia cells grew rapidly when exposed to folic acid. Using anti-folates (like methotrexate) to reduce the presence of folic acid in the blood, Farber was able to temporarily halt the course of the deadliest childhood cancer in that time period. The development of chemicals to treat cancer was an important development, though chemotherapy comes at a high price. The drugs are also toxic to the body’s other fast-growing cells, and can have damaging side effects.
Over 250 types of cancer have been described, and each type of cancer causes different cellular changes in the malignant cells. The great variety and complexity of these cells makes cancer a difficult disease to fight. As our understanding of genetics, tumor cells, and the immune system grows, better treatments will be discovered at an ever-increasing pace.
Biotech Companies Find Cancer Therapies
Cancer Biotech Companies
Who are the biggest players in the world of biotech cancer research? These companies all have major research initiatives to find better treatments and cures for various types of cancer:
Bristol Myers Squibb has been researching and developing cancer treatments since the 1970’s, when Richard Nixon declared a “war on cancer.” Conventional chemotherapeutic drugs, tumor growth suppressors (signal transduction inhibitors) and immunological therapies are under development.
Merck & Co. has a team devoted to the discovery of treatment options for skin cancer, along with many other cancer types (ranging from soft tissue sarcomas to breast cancer). Immunotherapeutics, chemotherapeutics, targeted biologics, and other drugs are currently being investigated through clinical trials.
Roche Holding AG: Another biotech company racing to find cures and treatments for cancer, Roche is developing many drugs to suppress and stop cancer growth and to detect cancer with novel screening tests. Targeted biopharmaceuticals which use antibodies specific to tumor cells are among the types of drugs under development by Roche.
Teva Pharmaceutical Industries Ltd. has partnered with the National Cancer Coalition to help patients gain access to cancer treatments in the developing world. Teva has drugs to treat non-Hodgkin's lymphoma, Chronic Lymphocytotic Leukemia (CLL), and promyelocytic leukemia (APL). Research on novel compounds and the development of pharmaceuticals to fight malignant cells is ongoing.
GlaxoSmithKline Plc also has a commitment to the developing world, and is engaged in the fight eliminate infectious and parasitic diseases common to tropical regions. In addition, GlaxoSmithKline has a reduced cost structure for patients receiving patented drugs (including cancer drugs) in developing countries. This company is a leader in developing cutting-edge pharmaceuticals, including immunomodulators for solid tumors, targeted antibodies against specific cancer types, and kinase inhibitors, which help to inhibit tumor growth.
Different types of cancer affect populations differently: the highest rates of stomach cancer are found in East Asia, for example, and Eastern Europe has the highest death rate from lung cancer. Environmental and genetic factors affect cancer rates.
The American Cancer Society released statistics for the United States in 2011: lung cancer is the leading cause of cancer death among men and women, primarily due to cell damage induced from smoking cigarettes. Other cancers do not affect men and women equally: esophageal cancer is more common in men than women.
While men and women both get breast cancer, the rates of breast cancer are remarkably lower for men than women. It doesn't rate in the top ten cancers for men, but is the second leading cause of cancer deaths in women. Prostate cancer doesn't affect women at all, but is the second leading cause of cancer deaths in men.
Chemotherapy Agents to Treat Cancer
Types of Cancer Treatments
There are many cancer treatment options available in the modern era. The following therapies may be used in isolation or in combination to attack malignancies:
Chemotherapy and Biotechnology
Toxic chemicals are used to destroy cancer cells. Many chemotherapeutic drugs are not specific to the cancer cells, so significant side effects may result from taking the medications. Chemotherapy may ease cancer symptoms, control the malignancy, or cure the cancer. When chemotherapy is used in combination with another technique (like radiation therapy), it is called adjuvant chemotherapy. The type of chemotherapy used will depend on the type of cancer, as different agents work better for different malignancies. Some forms of cancer do not respond well to chemotherapeutic drugs.
Biotechnology companies are developing new chemotherapy drugs, including targeted therapies. The targeted drugs are designed to attack specific markers on cancer cells, reducing the side effects of the drug. Another approach uses antibodies attached to the chemotherapy drug: the antibody seeks out the cancer cells and delivers the drug directly to the source. Another development is the use of fat molecules called liposomes to deliver the drugs to the cancer cells – this reduces the amount of side effects experienced by the patient.
Since cancer cells can become resistant to chemotherapy (the cells develop molecular pumps to actively eject the toxic drugs from the cells), new drugs are being developed to shut down the pumps in cancer cells. This helps to overcome drug resistance, which can become a problem when treating malignancies.
Another angle is the development of chemoprotective drugs. These drugs help protect organs which may be damaged by chemotherapy. An example of a chemoprotective drug is N-Acetylcysteine, which protects against the effects of a chemotherapy drug called cisplatin. N-Acetylcysteine prevents cisplatin from binding to cells – since N-Acetylecysteine does not cross the blood-brain barrier, it could be used in combination with cisplatin. The cisplatin would reach the brain and kill tumor cells there, but the N-Acetylcysteine has the potential to prevent organ damage from this drug throughout the rest of the body.
Monoclonal Antibodies in Cancer Therapy
Biotech Advances in Immune Therapies for Cancer
One of the newest cancer treatments involves the use of immune drugs. Monoclonal antibodies are designed to attack a specific characteristic on cancer cells – these antibodies will not attack the body’s typical cells, but only the defective cancer cells.
The antibodies are able to work in several ways: they may stop the growth of blood vessel formation in tumors (angiogenesis), deliver chemotherapy drugs or radiation specifically to a cancer cell, bind with growth receptors to prevent cancer cell division, or simply make the cancer cells more obvious to your own immune system by attaching certain proteins that trigger the patient’s own immune reaction.
An example of this drug class includes Ibritumomab, which couples radioactive particles to a monoclonal antibody. The antibody seeks out non-Hodgkin’s lymphoma cells and delivers the radiation directly to the affected cells, while preserving normal cells.
Immune therapies do have side effects, however, including flu-like symptoms, rashes, diarrhea, and allergic reactions. Occasionally, the drugs may cause lowered blood cell counts, which can be extremely dangerous. Many of these drugs are still experimental and are in clinical trials, while others (like Provenge for Prostate Cancer) are currently in use with proven efficacy.
Genomics Aids Cancer Treatment in Breast Cancer
Diagnostic Tests for Cancer
The early detection of cancer is as vital as the development of new treatments. Finding cancer cells before they have had a chance to metastasize throughout the body is a critical element of the war on cancer. Blood tests for cancer, genetic testing for cancer, and various types of screening tools are under development by several biotechnology companies.
Cancer marker tests are one common detection method. These tests measure markers, such as Prostate Serum Antigen (PSA), in the blood. Cancer marker tests may be used to identify cancer and to monitor the efficacy of cancer treatment in an individual.
With ever increasing treatment options, newer diagnostic tests identify the specific genome of the cancer cells. Once the genome has been studied, the most appropriate treatment may be selected: this is called genomics.
A very personalized approach to cancer is enabled with these tests, which are able to detect specific mutations that might respond to certain chemotherapy drugs or other targeted biological agents.
An example of genomics in action is the case of a young woman who entered the Dana Farber Institute with melanoma. The skin cancer had metastasized: through the use of genomics, the team found that her particular melanoma actually had a mutation called KIT – a mutation usually seen in chronic myelogenous leukemia, not melanoma. The therapy of choice was unusual: they used a drug called Gleevec, which is actually designed for CML, not melanoma.
Because of the specific genetic mutations of her melanoma cells, she was completely cured of melanoma with a drug designed for CML. She is the first case of metastatic melanoma to experience a complete cure.
The use of designer drugs and advanced screening techniques are increasing due to the efforts of biotech companies and other research entities. As we move forward in the 21st century, new discoveries and a better understanding of genetics, immunology,and cell growth characteristics will spawn cures for various types of cancer.