Are Stem Cells the Answer to the Cancer Question?
Sources: American Cancer Society; Medical News Compilation
In 2012, approximately 1.6 million people will be newly diagnosed with cancer and approximately 577,000 Americans are expected to die from the disease (American Cancer Society).
There has been a lot of press deveoted to the the potential of targeting cancer stem cells directly to treat and eliminate the disease. Unlike mature cells in the body, stem cells have the ability to self-renew and/or mature into another type of cell with a more specialized function, such as a muscle cell, a red blood cell, or a brain cell. This is one reason they have been investigated extensively as a means for repairing or even growing new tissue and organs. Genetic mutations or other factors may give rise to CSCs that possess the same capacity for self-renewal and can mature into cancer cells that comprise the tumor.
The traditional therapy for cancer has been, surgery, chemotherapy and radiation, the later two of which have limited selectivity in targeting only cancer and can easily damage healthy tissue in the process. Recently, however, pharmaceutical companies have been purshasing assets which appear to be directed to cancer stem cell research and development. Dainippon Sumitomo Pharma Co., Ltd. has announced plans to acquire Boston Biomedical, Inc., for up to $2.63 billion. Boston Biomedical’s lead program for inhibiting cancer stem cells in addition to other cancer cells, BBI608, is entering Phase 3 (advanced) trials in patients with colorectal cancer.
Geron Corporation is another company making the plunge into stem cell inhibition with Imetelstat [GRN163L], a telomerase inhibitor that has been shown to effectively inhibit cancer stem cells from a broad range of tumors. Imetelstat is in Phase 2 trials for non-small cell lung cancer, metastatic breast cancer, essential thrombocythemia and multiple myeloma.
ImmunoCellular Therapeutics Ltd. is developing a vaccine, ICT-107, which is in Phase 2 development for the treatment of glioblastoma multiforme [GBM]. Verastem, Inc. (The name really tips it) is a new upstart biotech company expectd to file an investigational new drug application [IND] with the U.S. Food and Drug Administration [FDA] to initiate a Phase 1 clinical trial of its product, VS-507.
If names like the smaller Eclipse Therapeutics, Inc., Formula Pharmaceuticals, KaloBios Pharmaceuticals, Inc.,, OncoMed Pharmaceuticals, Stemica LLC and Stemline Therapeutics don’t sound familiar then perhaps they will make some news in the next 2 years. All of them have produced or are producing antibodies, vaccines, and molecular products designed specifically to target cancer stem cells. Some of them already have products in clinical trials.
Posted by: Gayle R. Lewis, Esquire
Re-thinking Chemotherapy.
Source: Medical News Today; Science journal
Chemotherapy used to be a very blunt instrument. The chemicals used in chemotherapy were originally developed for destruction of human life of the battlefields of World Wars (ie. Mustard gas). This is once of the reasons why chemotherapy causes injuries to other organs, damaging symptoms such as hair loss, and even secondary cancers. More recently, oncologists (doctors who specialize in cancer treatment) have benefited from advances in genetics to sharpen chemotherapy. One of the newest advances is predicting the “life-cycle” of cancer cells so that doctors can target cancers which might be easier to kill. More accurately they can identify those cancer cells that are close to the end and can push them (chemically speaking) off the ledge.
For those of you who want the technical explanation, here it goes: (The rest of you can skip to the next paragraph) It all comes down to proteins -in this case BH3 peptides within the BCL-2 family. BCL-2 proteins cause apoptosis (the process of cellular death) and scientists believe that they can influence this process by adding BH3 peptides to tip cell balance in favor of apoptosis vs. replication. In a very literal sense, the scientists are able to trick the cancer cells into committing cellular suicide. In the admittedly small study of tumors from 85 patients, including myelomas, leukemias and ovarian cancers, the chemotherapy was most successful against tumors which had the greatest mitochondrial tiping in the laboratory.
It may not sound like much to most people, but this is a radical new way of looking at exactly how chemotherapy works. It has been thought for years that chemotherapy attacks rapidly proliferating (fast growing) cells which eventually group to form tumors. This doesn’t really explain why chemotherapy doesn’t work effectively against skin cancers, for example. The idea that chemorherapy is effective mainly against cancer cells which are close to dying may aid in the development of new chemotherapy agents which have less collateral damage.
Posted by: Gayle R. Lewis, Esquire
Radiation Still Common Treatment for Cancer
Source: MD Becker Partners, Life Science Digest; American Cancer Society
An estimated 1.1 million patients were treated with radiation in 2009, representing an increase of 15% from 2007 according to a market research study published by IMV Medical Information Division.
The clinical application of radiation therapy in oncology (using high-energy radiation to shrink tumors and kill cancer cells) dates back to the early 1900s when radium was used to successfully treat a pharyngeal carcinoma in Vienna. By the 1930s, fractionated X-rays were used to cure a group of patients with inoperable cancer of the larynx. Today, radiation therapy remains a cornerstone of cancer treatment and is often used in combination with surgery and chemotherapy.
Radiation can be delivered to a cancer patient using several techniques. These include using a machine outside of the body (external-beam radiation therapy), placing radioactive material in the vicinity of cancer cells (internal radiation therapy, or brachytherapy), and systemic radiation therapy using injected substances (radiopharmaceuticals) that travel in the blood to seek and destroy cancer cells.
Despite numerous medical and scientific advances following its clinical introduction more than a century ago, radiation therapy is an important and growing treatment option for breast, prostate, lung and other cancers. A recent article in the Journal Cancer suggests that 52% of all cancer patients should receive radiation. The American Cancer Society expecting approximately 1,596,670 new cancer cases to be diagnosed in 2011.
However, most types of radiation do not specifically attack cancer cells and cause injury to normal tissues surrounding the tumor. The goal of radiation therapy is to maximize the dose delivered to tumor cells while minimizing exposure to normal, healthy cells. For Prostate Cancer patients, complications of radiation include: bleeding; irritation and pain; urinary frequency; urgency; and, incontinence. Radiation therapy directed to the chest is commonly employed to treat lung, esophageal, breast and lymphoma cancers. However, lung inflammation caused by radiation therapy, called radiation pneumonitis, is the most common complication.
Given the prominent role of radiation therapy in cancer treatment, the development of novel agents that protect normal tissue against the effects of ionizing radiation represents a large market opportunity and unmet medical need.
Post: Gayle R. Lewis, Esquire
Pancreatic Cancer is Slow to Reveal Itself.
Source: Nature Journal; BBC Health
US Scientists at the Howard Hughes Medical Institute and Johns Hopkins University have suggested that Pancreatic cancer may hide in the body for many years before patients fall ill to their disease, which is fatal 95% of the time.
Research hints at earlier opportunities to spot and treat the disease with the first mutations occurring up to 20 years before they become lethal. This aggressive cancer is unresponsive to conventional treatments and has likely metastasized (spread) by the time it is discovered.
In reviewing tissue samples from both primary (originating) tumors and metastatic (spread) tumors, the researchers took all of the genes and placed them in order -looking for mutations (changes in the genetic coding). The average metastatic tumor showed 61 disticnt cancer-related mutations. Of these, 2/3 were also found in the primary pancreatic tumour.
So what does all of this mean? “It means that there is a window of opportunity for early detection of pancreatic cancer,” says Dr. Bert Vogelstein of the Howard Hughes Medical Institute. So how slow is slow? Consider this, the researchers estimated that on average, it took 11.7 years for a single gene mutation in a pancreas cell to become a “mature” pancreatic tumor. Consider this as well, it took another 6.8 years on average before the cancer cells metastasized to another organ.
It is critical to note that once the cancer cells spread, patients had less than 3 years remaining before they passed away from their disease. So 20 years was the average time which patients lived with pancreatic cancer.
So, from start to finish, the development of the disease took more than 20 years on average. Surely medical science has advanced to the point where we can find pancreatic cancer within 20 years and save more lives? Surprisingly, not quite yet. Research such as this, which is underfunded (no one is paying for it) is not plentiful and the focus ultimately becomes upon surgical and chemotherapy (drug) advances rather than finding cancer earlier.
Chief executive Maggie Blanks rom the UK’s Institute of Cancer Research, has stated, “Survival rates have not improved in the past 40 years and whilst (while for those in the US) the disease is the UK’s fifth biggest cause of cancer death, it receives less than 2% of overall research funding.”
The Estimated number new cases of pancreatic cancer in the United States for 2010 is 43,140, resulting in 36,800 deaths. Pancreatic cancer is currently one of the only cancers not demonstrating any increase in survival rates.
~Posted by D.M. Schwadron, Esquire
Gene test to aid Cancer treatment
Source: BBC Health; The Lancet Oncology
It is a fact of chemotherapy (chemical treatment for cancer) that some patients simply don’t respond to medications. Or that they stop responding over time. With more than 45,400 women diagnosed with breast cancer every year, scientists have been furiously trying to decode our genetic patterns for reasons such as this.
Starting with 829 genes present in breast cancer cells, the focus has been drawn to just 6 genes which appear to impact the efficacy (medical effectiveness) of chemotherapy. If they are correct then it may be possible to develop a simple test to determine whether or not certain drugs, in this case paclitaxel, will be beneficial to patients. Another one to watch.
~Posted by D.M. Schwadron, Esquire