Cells throughout the body make a type of protein called B7-H3 (also known as CD276). These proteins stick to receptors on the surface of immune cells (T-cells) and help cancer cells hide from the body’s natural immune system.
When high levels of the B7-H3 protein are found on tumors, it exhausts the T-cells’ search for cancer cells. This allows cancer to grow.
Biomarker testing can measure the amount of B7-H3 in a tumor. Most often, immunohistochemistry (IHC) tests are used to determine the percentage of a tumor’s cells with B7-H3. Higher levels may indicate a patient is a candidate for immunotherapies being studied in clinical trials.
Immunotherapy drugs can target the B7-H3 molecule and help stop the signal telling the body’s T-cells to stand down. If a tumor has high amounts of B7-H3, it can be a strong target for drugs called antibody-drug conjugates (ADCs).
Clinical trials for many esophageal cancer patients are also looking into the use of immunotherapy on patients based on their B7-H3 scores.
Your treatment plan will be unique and dependent on several factors. Ask your doctor how your biomarker test results are informing your treatment plan and if you qualify for any clinical trials.
