There is a lot of promise in orthodox medicine figuring out how to harness Mother Nature’s natural immune ability to fight cancer.
It has been wisely said that cancer is really a disease of the immune system. According to this view, we all make cancer cells but the immune system spots them and removes them, before they ever started on forming a tumor.
If this is true then we can argue that when someone gets cancer, their immune system has failed.
Conversely, anything which can persuade the immune system to actively and vigorously attack a tumor is probably the best way to go.
“Anti-cancer diets”, supplements and other safe holistic therapies are often nothing more than ways to boost the performance of the immune system.
Such a therapy is Dendritic Cell Therapy, or DC therapy, though most people refer to it as the Dendritic Cell vaccine. In a nutshell, it's an approach to cancer treatment that uses your body's own immune system to fight cancer. There have even been some reports of complete turn arounds, including some late-stage cancer patients — essentially hopeless cases—getting dramatically well.
But that's not all. Not only is DC therapy a promising treatment for advanced cancer, it may also function as a useful tool, to prevent us getting cancer in the first place.
Dendritic cells: What they are and what they do
So-called dendritic cells are a type of immune cell found in mammals. They function as a messenger cell or information carrier that helps activate a type of immune system cell called T cells, alerting the T cells to potential threats to the body. Once alerted to danger, the killer T cells circulate throughout the body to destroy the foreign invaders.
Dendritic cells are present in the skin and other tissues that have contact with the external environment, such as the lining of the nose, lungs, and stomach. They exist in an immature state in the blood. But although they're extremely powerful, dendritic cells don't occur in big numbers in the body; not enough enough to prompt a significant immune response to cancer.
But Dendritic Cell Therapy boosts the number of dendritic cells in the body so there are more of them. Cancer treatment vaccines as a whole are designed to activate B cells and killer T cells. They alert those cells to the foreign invader, in this case tumor cells.
Dendritic cells are antigen-presenting cells. They basically serve as messengers between the innate immune system (your body's first line of defense) and the adaptive immune system, which remembers pathogens that it's seen before, and mounts ever stronger attacks against them. This part of the immune system is called "adaptive" because it's the body's system for preparing for future challenges, not merely for the antigens it's seeing now.
To make the dendritic cell vaccine, researchers take a patient's dendritic cells and expose them to immune cell stimulants. This prompts dendritic cell development. After that, the dendritic cells are exposed to antigens from the patient's cancer cells. Think of this as showing all your neighbors a picture of the criminal, so they'll know him if they see him.
Then, the combination of dendritic cells and antigens is injected back into the patient. From there, the dendritic cells work to program the T cells so they know exactly what to attack.
So far, this approach seems to work well for most patients, except those with depressed immune systems. Unfortunately, chemotherapy and radiation depress the immune system. The Dendritic Cell Therapy may also be inappropriate for patients who are pregnant, who suffer from active autoimmune disease (such as rheumatoid arthritis), or who have recently received a blood transfusion.
This works on a growing list of cancers…
This treatment has some of the biggest players in allopathic medicine nodding their heads. Even the VP of Research at the American Medical Association, Dr. Harmon Eyre, said of Dendritic Cell Therapy, "Patients' responses are far out of proportion to anything that any current therapy could do."
Researchers feel immunotherapy with dendritic cells shows a lot of promise even for some of the toughest cancers, such as advanced prostate cancer. Several trials have shown promise in extending survival for prostate cancer patients.
Melanoma and kidney cancer appear to respond best, but the vaccine has also shown documented benefit in B cell lymphoma, myeloma, colon cancer, ovarian cancer, breast cancer, and renal cell cancer, among others.
At least 20 trials are in progress right now, each one examining the effectiveness of Dendritic Cell Therapy on everything from ovarian and lung cancer to Stage IV Melanoma. The best time to attempt Dendritic Cell Therapy appears to be when the disease is stable and the patient isn't going through chemo or radiation, when a patient is at risk of the disease recurring, or when all other options have been exhausted.
The future for immunotherapy is bright
Some experts predict that dendritic cell vaccines will be used as a stand-alone therapy in the future, at least in some patients. It's also likely to be used in combination with drugs that target suppressor pathways in patients with metastatic cancer (i.e. cancer that has spread beyond its original location).
I think the outlook for immunotherapy is very exciting. In Issue 140, I talked to you about the new leukemia treatment that involves T cell "reprogramming." In this approach, all T cells are coded to attack only cancerous cells. From there, they regenerate and keep attacking till the cancer is gone. This news about the Dendritic Cell vaccine is even better, from what I can learn.
It's nice to know researchers are at last tapping the true power of the body's natural immune system. One researcher even said these vaccines could possibly lead to the complete prevention of cancer.
That's a bright future I'm looking forward to.
Meanwhile, take steps on your own, at home, to make sure you never get cancer in the first place. We recommended a good one in the last issue. If you missed it, scroll down and read about it now.
Immune Responses by Dendritic Cell Vaccination
Anti-Tumor Immune Response: The Foundation
Even when a tumor is successfully removed, a few cells are almost invariably left behind. These often are treated with radiation or chemotherapy to keep them from growing, but certain types of aggressive, malignant cells are especially difficult to contain.
Among the most persistent are glioblastoma multiforme tumor cells. This cancer is among the most common types of brain tumors. They tend to grow quickly, invade surrounding tissue, and recur frequently. Survival rates have historically been extremely low.
Dendritic cell immunotherapy - pioneered at Cedars-Sinai in Los Angeles to fight these malignant brain tumors - creates a vaccine from the cells of a tumor that has been surgically removed.
In the laboratory, cancer proteins extracted from the tumor are combined and cultured with dendritic cells taken from the patient's blood. Dendritic cells, also known as antigen-presenting cells, identify tumor cells for the immune system's cancer-fighting T-cells. The new dendritic cells resulting from this union are re-injected into the patient, where they recognize and destroy any lingering malignant tumor cells. Several injections of a small amount of the vaccine are typically scheduled over a six-week period.
Current Developments and Research Progress
Although significant advances have been made using radiation, surgery and chemotherapeutics to increase the survival of patients with glioblastoma multiforme (GBM), these advances have been modest with only 2-3 month increases in survival. In contrast, the Institute has confirmed the ability to mount significant biological activity through dendritic cell vaccination approaches and provide a rationale to address the infiltrating pockets of tumor cells. One compelling aspect of the Cedars-Sinai studies has been both clinical and mechanistic evidence for the ability of immunotherapy to sensitize glioblastomas to chemotherapy(6). Not only does the immunotherapy itself induce cytotoxicity (quality of being toxic to cells), but it makes tumors more amenable to drug therapy. The Institute recently demonstrated that temozolomide improves the immunogenicity (ability to provoke an immune response) of glioblastomas and cancels the immunosuppression seen both locally and systemically.
Scientists at the Neurosurgical Institute have shown that dendritic cell immunotherapy (DCIT) induces a cytotoxic T cell response to autologous tumor and specific-tumor associated antigens in a subset of patients with glioblastoma (1,4,6,7). The dendritic cell vaccination also induces cytotoxic memory T cells to localize in intracranial tumor in a subset of patients (1,4,6,7). In these studies, vaccinated glioblastoma patients have prolonged survival compared to RTOG recursive partitions and cohorts controlled for age, Karnofsky performance scores, and degree of resection (1,4,6,7). In the past, the survival of glioblastoma patients within each of the Institute's Phase I and II trials was highly correlated with whether a cytotoxic T cell response was observed after dendritic cell vaccination.
When de novo (newly treated) glioblastoma patients from our Phase I and Phase II trials were retrospectively partitioned into 1) those patients that received chemotherapy after dendritic cell vaccination; 2) those that did not receive chemotherapy and 3) those patients that received chemotherapy alone -- patients who received chemotherapy following immunotherapy demonstrated longer progression free survival and overall survival compared to the other two groups.
Recent Publications
1. Wheeler CJ, Black KL, Liu G, Mazer M, Zhang X, Pepkowitz S, Goldfinger D, Ng H, Irvin D, Yu JS. Vaccination elicits correlated immune and clinical responses in glioblastoma multiforme patients. Cancer Res 68(14):5955-64, 2008.
2. Akasaki C, Liu G, Chung NH, Ehtesham M, Black KL, Yu JS. Induction of a CD4+ T regulatory type-1 response by cyclooxygenase-2 overexpressing glioma. J Immunology 173(7):4352-9, 2004.
3. Liu G, Yu JS, Zeng G, Yin D, Xie D, Black KL, Ying H. AIM-2: A Novel Tumor Antigen Is Expressed and Presented by Human Glioma Cells. J Immunotherapy 27:220-6, 2004.
4. Yu JS, Liu G, Ying H, Yong WH, Black KL, Wheeler CJ. Vaccination with tumor lysate-pulsed dendritic cells elicits antigen specific cytotoxic T cells in patients with malignant glioma. Cancer Res 64:4973-9, 2004.
5. Liu G, Ying H, Zeng G, Wheeler CJ, Black KL, Yu JS. HER-2, gp100, and MAGE-1 are expressed in human glioblastoma and recognized by cytotoxic T cells. Cancer Res 64:4980-4986, 2004.
6. Wheeler CJ, Das A, Liu G, Yu JS, Black KB. Clinical responsiveness of glioblastoma to chemotherapy after vaccination. Clin Cancer Res 10(16):5316-26, 2004.
7. Yu JS, Wheeler CJ, Zeltzer PM, Finger D, Lee PK, Pins R, Yong WH, Thompson RC, Riedinger M, Zhang W, Black KL. Vaccination of malignant glioma patients with peptide-pulsed dendritic cells elicits systemic cytotoxicity and intracranial T-cell infiltration. Cancer Res 61:842-847, 2001. (selected as cover illustration)