4 months in the placebo group. (P=0.01) [Kyogo et.al] an earlier study by Nestle et.al (1998) had showed promising results. In that study, a small group of renal cancer patients were vaccinated with RNA-transfected dendritic cells. T cell response was noted in most of the treated patients and a follow up study conducted after 19 months showed that 7 out of 10 patients still survived. [Jian et.al, 2008] Other vaccines such as the 'Heat shock protein' (HSP) vaccine introduced in clinical trials have only showed mixed results and have not been responsive in all patients. Oncophage is one HSP that has been approved in Russia for renal cancer patients. [Kyogo et.al]
TREGS (a new outlook at Immunotherapy)
A relatively new and much less explored path in the immunotherapeutic research is the focus on the role of TREGS (regulatory T cells). All the techniques discussed above were concerned with boosting the host with additional T cells or tumor infiltrating Lymphocytes. However the results from these therapies have thus far only indicated marginal response. Hence, priming up the immune system may not be only solution to the problem. Also since tumors are intrinsic, any immunotherapy designed against it has the potential to cause autoimmune complications. Research has also shown that tumors evade the natural immunity by producing immunosuppressive factors such as IL-10 TGF-?, and VEGF. Therefore, immunotherapeutic research would be more effective if it also focuses on this immunosuppressive aspect of tumor. [Tyler J. Curial]
Tregs are involved in the immune evasive functions of tumor cells. Studying Tregs in the cancer microenvironment, therefore presents another approach to the treatment of cancer. It is known from previous studies that Tregs resemble CD4+CD25+ Leukemia cells. Using this phenotypical similarity, Barnett et.al (2005) studied the effects of the denileukin diftitox, an FDA approved antineoplastic agent, used in the treatment of T cell Lymphoma. Patients who underwent a single infusion of denileukin diftitox (9 or 12 ?g/kg) exhibited a remarkable reduction in Tregs. The results were similar for patients with different types of cancers for a period of 30 days. Another study by Dannull J., et al. (2005) also attested to reduced levels of Tregs and consequent reduction in suppression induced by CD4+CD25+ T cell in response to treatment with denileukin diftitox in renal cancer...
Separate studies in mice have also indicated that Tregs suppression leads to more effective adoptive T cell therapy.
We are at the threshold of new and entirely different approach to the management of cancer. Though we are still in pursuit of effective cancer vaccines, Cancer Immunotherapy has developed much over the last decade. Many multi-antigenic cancer vaccines are now in the last phase of clinical trials. Personalized cancer treatment in the form of adoptive T cell therapies and entirely different perspectives of cancer research such as the Tregs suppression have provided more strength to our fight against cancer. In particular, this new outlook (Tregs suppression) complements the effect of the different types of cell transfer therapies that are aimed at increasing the immunity to cancer. Though we are still a long way from understanding all the intricate cellular mechanisms that underlie cancer, we are definitely witnessing a paradigm shift in immunotherapeutic treatment modalities and are fast progressing on our way to find a cure to this dreaded disease.
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6) Oikawa Takehir & Kawai Koji et.al, 'Adoptive transfer of autologous cytotoxic T. lymphocytes for metastatic renal cell carcinoma', Univ. Of Tsukuba, BCG, Vol 26, pg 39-41.
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However, because healthy cells can repair damage more effectively, the cancerous cells in an area sustain more damage from the treatment. In order to help the healthy cells recover from the radiotherapy, after five days of treatment a patient will often have two days without the treatment. Radiotherapy may be used as a curative treatment, by which the aim is to completely cure the cancer and destroy the tumor. When
The current protocols of T cell transduction involve in vitro activation to achieve T cell proliferation that is required for effective retroviral infection. Adoptive transfer of such minimally stimulated cells will reveal whether in vivo transfer of TCR transduced resting T cells provides more effective protection from disease and better memory development than transfer of fully activated T cells. TCR gene transfer can also be used to produce antigen-specific CD4+ helper
Immunotherapists can provide sensitive and accurate cancer diagnostic tools for the successful treatment of the disease and to stop it well in its tracks (cancerresearch.org, 2009). The outward advantages of immunotherapy are as follows: certain drugs have fewer side effects and offer patients a higher quality of life, bolstered anti-cancer effectiveness and rates of survival, benefits are often reaped quickly for the patient (cisncancer.org). The disadvantages are as follows: some
, 2006). He visualized and described the malignancy process. He suggested that early that "cells of tumors with unlimited growth" would develop with the elimination of chromosomes, which inhibit the growth. The multiple genetic alterations in these inhibiting chromosomes are today known as TSGs. The theory supposes that cancer arises from functional defect or absence of one or more TSGs. Clinical trials of TSG gene replacement therapy for breast cancer
Merkel Cell Carcinoma is a relatively rare, but highly aggressive type of skin cancer. Discovered in 2008, it is typically caused by a virus known as Merkel Cell Polyomavirus (MCPyV). At times, the disease may be known as APUDoma, a primary neuroendocrine carcinoma of the skin, or primary small cell carcinoma. However, from a pathological perspective, 80% of Merkel Cell Carcinoma (MCC) are called by the polyomavirus. Interestingly, the virus
Who.int/mediacentre/factsheets/fs297/en/ Colon Cancer." (2008). Mayo clinic.com. Retrieved on February 27, 2008 at http://www.mayoclinic.com/health/colon-cancer/DS00035 Colon Cancer Treatment." (2007). National Cancer Institute. Retrieved on February 27, 2008 at http://www.cancer.gov/cancertopics/pdq/treatment/colon/patient Lee, Dennis. "Colon Cancer (Colorectal Cancer)" (2007). Medicine net.com. Retrieved on February 27, 2008 at http://www.medicinenet.com/colon_cancer/article.htm Myers, Donna. (2008). "Overview of Colon Cancer Symptoms." About.com: Health. Retrieved on February 27, 2008 at http://coloncancer.about.com/od/cancerprevention/a/Cancer_Symptoms.htm The colon is part of the body's digestive system, which consists of the esophagus, stomach,