Cancer Monoclonal Antibodies: A Targeted Approach to Cancer Treatment
Author : Pratik Ghevade | Published On : 20 Jan 2025
Monoclonal antibodies are laboratory-produced molecules engineered to serve as clone copies of a unique antibody. They can be designed to bind to specific proteins expressed by tumor cells, including antigens predominantly found on cancer cells. When targeted antibodies bind to tumor antigens, they can help the body's own immune system recognize and destroy cancer cells through various mechanisms.
Types of Monoclonal Antibodies Used in Cancer Treatment
Naked Monoclonal Antibodies
Naked Cancer Monoclonal Antibodies work directly by binding to specific cancer cell surface antigens and exerting anti-tumor effects. For example, the antibody Rituximab targets the CD20 antigen on B-cell lymphoma cells. Binding triggers cell death through mechanisms like antibody-dependent cellular cytotoxicity (ADCC) and complement-dependent cytotoxicity (CDC).
Antibody-Drug Conjugates
Antibody-drug conjugates link potent chemotherapy "payloads" to monoclonal antibodies. The antibody delivers the toxin directly inside cancer cells when the antibody binds to antigens on the cell surface. Examples include Trastuzumab emtansine for HER2-positive breast cancer and Brentuximab vedotin for Hodgkin's lymphoma. This spares exposure to healthy cells, concentrating drug delivery within the tumor.
Bispecific T Cell Engagers
Bispecific T cell engagers are engineered antibodies that can bind to tumor cells as well as T cells. This brings cancer-killing cytotoxic T lymphocytes directly into contact with tumor cells to induce death via apoptosis. Blinatumomab is approved for certain types of leukemia.
Chimeric Antigen Receptor (CAR) T Cell Therapies
CAR T cell therapies involve collecting a patient's own T cells and genetically engineering them to express a chimeric antigen receptor recognizing a specific cancer antigen. The CAR T cells are grown in large numbers in the laboratory and infused back into patients to seek out and destroy cancer cells bearing that antigen. Approved therapies target antigens on certain leukemias and lymphomas.
Mechanisms of Action and Clinical Applications
Antibody-Dependent Cellular Cytotoxicity (ADCC)
Many naked monoclonal antibodies induce killing of tumor cells indirectly via ADCC. The antibody binds to tumor antigens and triggers immune cells like natural killer cells to release toxic granzymes and perforins, punching holes in cancer cell membranes. ADCC contributes to the efficacy of antibodies like rituximab, trastuzumab, cetuximab.
Complement-Dependent Cytotoxicity (CDC)
Antibody binding to tumor antigens can trigger complement activation, a cascade of protein clippings leading to formation of membrane attack complexes inserting into tumor cell membranes. Water influx causes osmotic bursting of cancer cells. CDC is an important mechanism of some monoclonal antibodies such as rituximab and alemtuzumab.
Blocking Tumor Growth Factor Signaling
Some antibodies block growth factor receptors on tumor cells or neutralize the growth factors themselves. This prevents downstream signaling driving uncontrolled proliferation. Examples include trastuzumab (HER2 receptor), cetuximab and panitumumab (EGFR receptor).
Monoclonal Antibodies for Common Cancer Types
Breast Cancer
Trastuzumab targets HER2-positive breast cancer, improving outcomes when given with chemotherapy as well as in metastatic or adjuvant settings. Pertuzumab in combination with trastuzumab and docetaxel is another targeted option.
Colorectal Cancer
Cetuximab and panitumumab block EGFR signaling in metastatic colorectal cancer patients with wild-type KRAS genes.
Non-Small Cell Lung Cancer
Necitumumab, atezolizumab, and ramucirumab are monoclonal antibodies benefiting subsets of non-small cell lung cancer patients.
Head and Neck Cancer
Cetuximab has activity against recurrent/metastatic head and neck squamous cell carcinoma.
Prostate Cancer
Daratumumab targets CD38 antigen on multiple myeloma cells and some prostate cancer subtypes.
As cancer biologies are better understood, monoclonal antibodies exert fewer side effects than chemotherapy by precisely hitting tumor vulnerabilities. Combining these targeted agents with each other or cytotoxic drugs often improves outcomes more than either approach alone. Advanced antibody engineering is continually expanding applications to help transform once difficult-to-treat cancers into chronic diseases. Overall, monoclonal antibodies deliver a crucial personalized dimension in the evolving field of precision oncology.
About Author:
Vaagisha brings over three years of expertise as a content editor in the market research domain. Originally a creative writer, she discovered her passion for editing, combining her flair for writing with a meticulous eye for detail. Her ability to craft and refine compelling content makes her an invaluable asset in delivering polished and engaging write-ups.
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