Gene - Direct Enzyme Therapy Treatment for Bowel Cancer

The bowel name referred to the small and large intestines were digestion of food takes place. The small intestines extend from the stomach to the large intestines. The large bowel or large intestines (colon) mostly responsible, absorbing water from the faeces. The last part of the large bowl is known as the rectum, leads to the anus. Bowel (colorectal) cancer is cancer of the colon or rectum and predominately arise in the large bowel. When cells in the colon divide uncontrollably, form a clump of malignant (cancerous) cells or produce a polyp (a clump of abnormal cells the size of a pea on the end of a stalk of normal cells) called an adenoma. Approximately five percent of polyps progress to life - threatening cancers. If the cancer is not removed sooner than later, cancerous cells could spread or metastases (secondariness) through the veins or lymph vessels to form in other parts of the body or in the liver. Once metastases occurs risk of death increases. The average age of bowel cancer begins 65 years old and then the odds increase later in life. Men are more likely to develop rectal cancer than women. The risk for bowl cancer is approximately ninety percent, linked to dietary factors and ten percent linked to genetic (inherited) factors. Researchers know vegetables including cabbage, broccoli, brussel sprouts, and cauliflower contain chemicals (for example isothiocyanates) contribute to reducing the risk or protecting against cancer. Whereas burnt meat contain cancer promoting chemical called cyclic amines. Also, history of colitis or Crohn's disease increases the chances of getting bowl cancer.

Bowl cancer is very common form of a cancer after lung cancer. In the United States, approximately 150,000 cases of colon and rectal cancer diagnosed each year. In Western countries, about six percent of the population develop bowel cancer at some time during their lives, and third leading cause of death due to cancer in the United States. Fortunately, forty to fifty percent of bowl cancer is curable by surgery. Symptoms of bowl cancer includes increase or decrease frequency of bathroom visits, change in the shape of stool, constipation, lower abdominal pain, weigh loss, anemia or low blood count, and blood in stool. Most of the time, symptoms of bowl cancer become apparent after the bowl cancer has progressed beyond the beginning phase or can grow for years without any symptoms. Colon cancer screening (colonoscopy - A flexible tube inserted into the anus and then threaded through to rectum to the end of the colon. The end of the tube has a camera by which a doctor can search for any polyps, which are snipped off, and later examined in the laboratory (biopsy) for any cancerous cells) is advisable as one of the best ways to prevent colorectal cancer, beginning at age 50 or sooner if previous family history is known. Rare complications for colonoscopy include heavy bleeding, intestinal perforation (poking a hole in the gut), adverse reaction to sedatives, and bowel infection.

When a biopsy confirms the presents of bowl cancer, treatment options include: Partial colectomy (The tumor and normal tissues on the either side of the diseased area in the colon are surgically removed, may require a temporary colostomy, an opening for solid waste from the bowel to a special bag a patient wears outside the body), Laparoscopic surgery (The surgeon removes section of the bowel and adjacent tissue by the use of flexible tube that has a small camera by which a physician observes on television type screen), radiation therapy (Radioactive pellets are inserted onto the cancerous area), and Chemotherapy (drugs administered intravenously or orally taken to kill the cancer cells). In some cases a combination of treatment options are chosen or advisable.

In 2005, study published in the Journal of Medicinal Chemistry today, scientists at the Institute of Cancer Research in the United Kingdom, lead by Professor Caroline Springer developed a series of powerful stealthy anticancer drugs, sneak into tumors and destroy them, without causing damage to surrounding healthy cells, often occurs during conventional chemotherapy treatment. The new drug delivery approach is called gene-direct enzyme prodrug therapy (GDEPT): The therapy involves sending a 'scout' enzyme to destroy a tumor. The enzyme is designed to attach and infiltrate only cancerous cells. The enzyme remains ineffective, until nontoxic drugs, called prodrugs are administered. These produgs only become active when they react with the 'scout' enzyme in the cancerous cells. Actually, the enzyme acts as switch to turn the harmless prodrug molecules, into potent cancer killing drug. The process insured to be successful by the fact prodrugs cross through the cell's membrane into the cell itself. Gene-direct enzyme prodrug therapy proven successful to treat breast cancer patients with a variety of eight prodrugs by either delaying tumor development or provided a treatment for a cure. Professor John Toy, Medical Director of Cancer Research UK said: "The benefits that his therapy could offer, in terms of more comfortable treatment and reduced side effects (Including hair loss, nausea, and fatigue), could greatly improve the quality of life for people living with cancer or allow larger doses to be prescribed. The real test will come when the produgs go to clinical trials and we are able to analyze closely how well the treatment works in patients."

In May 2007, report published in Cancer Research, scientists at the Institute of Cancer Research modified the technique of Gene - Direct Enzyme Therapy by succeeding to make bowel cancer cells commit suicide. Researchers added an extra gene (Carboxypeptidase (G2 - CPG2) - The gene is controlled so that it only becomes activated in the presence of telomoerase, an enzyme found in many cancers.) to the virus. The virus is programmed to switch on the gene only if it reaches the tumor. Then virus produces a protein that activates an otherwise harmless 'prodrug,' given separately. As a result, the DNA inside a cancer cell stops functioning or shuts down and dies. Lead researcher, Professor Carline Springer of the The Institute's Cancer Research UK Centre for Cancer Therapeutics said: "We have developed a smart method to selectively target cancer cells. Normal cells are separated because the virus doesn't produce the protein that activates the drug unless it is inside a tumor. We also see a significant "bystander affect": This means the cells killed by the virus or the drug release signals into the tumor that tell neighboring cancer cells to die too." Lab mice experiments with bowl tumors that received the therapy, lived twice as long as those that did not receive this treatment. Researchers suggest the modified GDEPT therapy could one day be used as a treatment for advanced bowel cancer patients that did not respond to standard chemotherapy. Cancer Research UK and The Institute of Cancer Research plan to proceed with clinical trials in the future, study the effectiveness of this new modified therapy treatment.