Alex Dean

Cancer Immunotherapy and CAR T Cell Therapy

Blog Post created by Alex Dean on Aug 29, 2018

When facing with cancer, the unwelcome guest, all what doctors do has only one purpose, that is, to control the crazy expansion and growth of tumor cells or even kill them. While the traditional way of cancer treatment such as chemotherapy and radiotherapy also proves to be effective, they are flawed by their horrible side effects accompanied. To save normal, healthy cells from being hurt, immunotherapy and targeted therapy have recently gained their prevalence.

Cancer Immunotherapy

Immunotherapy is the treatment of diseases like cancer by stimulating a person’s own immune system. Of course, to enhance the efficacy, techniques are needed to help the immune system work in a harder or smarter way. The main types of immunotherapy can be roughly included as follows:

Monoclonal antibodies

Immune checkpoint inhibitors

Cancer vaccines

Non-specific immunotherapies

Among them, immune checkpoint inhibitors and CAR T Cell therapy have attracted the most research focus. The following is a detailed explanation to CAR T Cell therapy.

CAR T Cell Therapy

Hailed by Hilde Almåsbak et al (2016) as “a game changer in cancer treatment”, CART T cell therapy has emerged in recent years as a highly promising way to treat some refractory or relapsed cancers. In 2017, the Food and Drug Administration (FDA) gave formal approval to the clinical trials of two CAR T-cell therapies. One of them is Kymriah™ developed by Novartis for the treatment of acute lymphoblastic leukemia (ALL), while the other, i.e. Yescarta, from Kite Pharma/Gilead, targets at relapsed or refractory large B-cell lymphoma in adult patients.

CAR, T Cells and CAR T Cell Therapy

As one can see from its name, at the center of CAR T cell therapy are two key terms: CAR and T cells. CAR stands for chimeric antigen receptor, ‘chimeric’ in the sense that the antigen receptor actually comes out of a combination of various sources. Wang et al (2017) define CAR as “a recombinant immunoreceptor combining an antibody-derived targeting fragment with signaling domains capable of activating cells, which endows T cells with the ability to recognize tumor-associated surface antigens independent of the expression of major histocompatibility complex (MHC) molecules.”

T cells or T lymphocytes are a type of lymphocytes or white blood cells in the immune system and take part in the inner workings of the system. T cells may either attach to other cells and kill infected cells in the body, or aid B lymphocytes to produce antibodies against infections. There are a wide range of functions which T cells can perform. For example, they can keep the memory of particular antigens to trigger fast body responses on the sighting of these antigens. Often called “the workhorses of the immune system”, in a sense T cells serve as a barometer of body health, with a falling level indicative of immunity-suppressing diseases.

CAR T cell therapy is a therapy which adopts engineered T cells expressing CARs to treat cancers. It belongs to the emerging school of immunotherapy called adoptive cell transfer (ACT), which promises to provide an alternative to surgery, chemotherapy, and radiation therapy, the traditional mainstay of cancer treatments.

How Does CAR T Cell Therapy Work?

The operating principle of CAR T cell therapy can be simply stated as follows: Agents are constructed from the T cells of the patient him/herself, and these re-engineered CAR T cells are then put back into the patient to scoop out and finish off the cancer cells.

It therefore involves the following steps:

Collect T cells from a patient
Reengineer T cells in the laboratory to make CAT T cells
Multiply the reengineered CAR T cells
Infuse the reenginnered into the patient
The CAR T cells produce the curative effect

Ever since the seminal work by Gross et al in 1989 in which they envisaged the feasibility of T cell treatment of human tumors, painstaking research has been conducted on CAR T cell therapy, resulting in highly encouraging findings and fantastic clinical effects. Work is now going on to understand and minimize the side effects of the therapy and take on the more challenging job of bringing the therapy to the test of treating solid cancers.

About the author

Among all varieties of chemicals BOC Sciences provided, small molecule inhibitors always rank high in its selling list. Signaling pathway is mysterious as it deals with how a specific signal is transmitted among cells. Recently, scientists have unveiled many signaling pathways, such as JNK Signaling Pathway, mTOR Signaling Pathway, RAS Signaling Pathway, Autophagy Pathway, etc. Please contact to know more.