Paradoxical Concentration Effect of Homodimerizing Antibody on Human Non-Small Cell Lung Cancer

In a groundbreaking study published in the journal Cancer Immunology, Immunotherapy, researchers from the University of Kentucky have made a startling discovery about the effects of a homodimerizing antibody on human non-small cell lung cancer cells. Contrary to conventional wisdom, the study found that increasing the concentration of the antibody actually reduces its potency, leading to a paradoxical concentration effect. The researchers analyzed the molecular species of the homophilic Herceptin under different concentrations using size exclusion chromatography and gel electrophoresis, and observed that high concentrations of the antibody reduce targeting, while also noting tumor growth arrest in xenograft mice after the tumor reached a critical size.

Key Takeaways:

• The researchers analyzed the effect of different amounts of a homophilic Herceptin on a human lung tumor cell line and discovered a paradoxical concentration effect, where higher concentrations of the antibody reduce its potency.
• The study used size exclusion chromatography and gel electrophoresis to examine the molecular species of the homophilic Herceptin under different concentrations.
• The researchers found that the therapeutic window is defined by tumor size and antibody concentration, suggesting that the therapeutic dose of the antibody should be matched with the tumor burden.
• The study concluded that conventional dose escalation protocols for antibody therapy may not be effective and that a reevaluation of dose-potency relationships is necessary.
• The University of Kentucky's Markey Cancer Center and the journal Cancer Immunology, Immunotherapy were involved in the research.
• The study highlights the complexities of antibody therapy and the need for further research into the mechanisms of antibody action.

Statistics:

• The researchers used size exclusion chromatography and gel electrophoresis to analyze the molecular species of the homophilic Herceptin under different concentrations.
• The study observed tumor growth arrest in xenograft mice after the tumor reached a critical size.
• The therapeutic window for the antibody was found to be defined by tumor size and antibody concentration.
• The study suggests that the therapeutic dose of the antibody should be matched with the tumor burden.

Sources:

• Cancer Immunology, Immunotherapy (Paradoxical concentration effect of a homodimerizing antibody against a human non-small cell lung cancer cell line, Cancer Immunology, Immunotherapy, 2009; 58(5): 749-58).
• University of Kentucky, Markey Cancer Center, Lexington, KY 40536 USA.
• H. Kohler, University of Kentucky, Markey Cancer Center.
• Cancer Therapy.
• Cancer Weekly, a publication of NewsRx.com.