Core Framework & Diagram What Are Tumor Antigens?

Tumor mutation burden (TMB) refers to the total number of somatic mutations in a tumor genome, expressed as mutations per million base pairs. High TMB means more tumor mutations, theoretically producing more neoantigens, more easily recognized by the immune system. Research shows high-TMB tumors have higher response rates to PD-1 inhibitors; the FDA has approved TMB-H (high TMB) as a pan-cancer immunotherapy indication.

Currently in clinical trial stages; some have entered phase 2/3 trials. In 2023, Moderna and BioNTech reported early data from their mRNA cancer vaccines showing positive signals. If trial results continue to be ideal, optimistic estimates suggest approval for specific cancer types within five to ten years. Large-scale deployment still needs to solve cost and production speed issues — currently each vaccine takes four to eight weeks to prepare.

NK cells don't need to recognize specific tumor antigens to launch attacks — this is the most important difference between NK cells and T cells. T cells need to recognize specific antigen-MHC complexes; NK cells use 'Missing Self' and 'danger signals' to recognize target cells, not depending on tumor-specific antigens. This means NK cells have irreplaceable recognition advantages over T cells for tumors with low neoantigen diversity or MHC-I deficiency.

CD19 is a protein expressed on B cell surfaces; virtually all B cell lymphomas and B cell acute lymphoblastic leukemia (B-ALL) highly express CD19. Because normal B cells also express CD19, CD19-targeting CAR-T will simultaneously clear both cancerous and normal B cells (B cell aplasia, manageable with immunoglobulin replacement therapy). CD19-CAR-T is one of the best clinically performing cell therapies to date.

Not necessarily — a very common source of confusion. Tumor markers (CEA, AFP, CA125, etc.) don't have high specificity — inflammation, benign diseases, even smoking can cause some markers to mildly rise. A single mildly elevated marker is usually not a cancer diagnosis basis; it needs combined interpretation with clinical symptoms, other test results, and dynamic changes (whether continuously rising on multiple tests). If a marker elevation is found, the correct approach is discussing with a doctor whether further imaging or endoscopy is needed — not immediately panicking.