Three Trends in Cancer Medicine Emerging

More Magic Bullets

The 60 minutes TV show profiled an interesting story about a potential cancer therapy being developed at Duke University’s cancer center. A researcher there has over 10 years developed a way to modify polio virus by adding a harmless molecular component to it so that it would not cause the polio infection itself. The goal is that the polio virus could be used as a therapy to stop a variety of cancers from brain cancer to pancreatic cancer to liver cancer and so on.  The idea is that a dose of the poliovirus is injected through a needle into a tumor in the brain and other organs . They are now conducting a clinical trial that was recently given the greenlight by the FDA. The aim of the phase 1 clinical trial is to inject the polio vaccine into tumors of a number of patients and see what dose levels would be optimal for this particular type of therapy.  So far they’ve been moderately successful at bringing about the tumor remission of the most deadly form of brain cancer called glioblastoma.  Cancer cells usually work in a stealth mode which defeats the impact of a patient’s immunity system . The modified poliovirus however causes a tumor to be visible by the patient’s immune system. Brain tumors in a few patients have completely gone away as a result of this interesting immunotherapy. Some of the patients have survived for more than 30 months. About half of the patients in the study have not fared very well because the dose was too strong which then gave a strong immunity response that caused them to swell in their faces and so forth. Some of those patients withdrew from the trial and eventually passed away as a result of their illness. The scientists working in the study learned key bits of information about establishing the best dose to treat patients. The ideas about immunotherapies have been in play for over the last 10 years and so a number of therapies have been developed. The Duke research team expects that in a short time they will be able to finish their clinical work and develop a commercially viable immunotherapy that fights a variety of solid tumors. The features of immunotherapies is that they harnesses the patients’ immune system to do most of the work of eradicating the cancer tumor cells .  During the initial few weeks of the cancer therapy the patient sometimes doesn’t see a positive result because the immunity system is in the process of mounting the attack on the tumor. If successful, over a time span of several weeks to months, the immunity system completely eradicated the tumor.  

This type of therapy would be of no use for treating really late stage cancer with multiple growing tumors or a cancer with really aggressive characteristics over a very short time span. So immunotherapy joins the trend that more and more cancer therapies are being developed. Oncologists now can use surgery, chemotherapy, radiation and immunotherapy as the tools that will help them find potential cures to fight cancer.  

Cancer Molecular Sub-typing 

Oncologist David Agus, who works at a USC cancer center, said that cancer is now being grouped in terms of its molecular or hormonal pathways that it uses. For example, in the case of breast cancer, hormone positive, hormone negative , HER2, and triple negative pathway subtypes. These ideas are part of a trend in cancer research of moving away from describing the disease in terms of its location of organs and so forth to more in terms of its molecular or hormonal profiles.  

Liquid Biopsies

Apparently another strong area of cancer research that is becoming a trend to be more commercial is the idea of using circulating tumor cells, circulating cancer stem cell’s or circulating DNA fragments of tumors passing through the blood and urine. The so-called liquid biopsy might someday soon become a very common practice in detecting whether or not the person has an active cancer.  Most cancers grow for a long time for many years maybe 10 years without actually being detected until finally the patient has a pain or bruise or symptom. And by then it’s just way too late for them to have an effective treatment because the cancer disease has grown to a late stage. Perhaps a routine liquid biopsy-like screening test can be developed that would detect the top 15 cancers that cause trouble for people.