PD-L1 is a potential predictive biomarker for cancers that utilise this pathway to inhibit the immune response
TUMOUR CELLS AND TUMOUR-INFILTRATING IMMUNE CELLS BOTH EXPRESS PD-L11,2
PD-L1 expression detected in immunohistochemistry staining of lung cancer tumour3
PD-L1 on tumour cells may lead to the inhibition of activated T cells.1
Tumour-infiltrating immune cell
PD-L1on tumour-infiltrating immune cells may also inhibit T cell activation and function.1,4
PD-L1 EXPRESSION ON TUMOUR-INFILTRATING IMMUNE CELLS
With their potential ability to inhibit T-cell function when expressing PD-L1, tumour-infiltrating immune cells are an emerging focus of cancer immunotherapy research.1,4 Different immune cells have been shown to express PD-L1.3
PD-L1 expression on macrophages detected in immunofluorescence staining of lung cancer tumour3
Arrows indicate macrophages (green; CD163) that express PD-L1 (red). Cell nuclei are stained in blue.
Arrows indicate macrophages (green; CD68) that express PD-L1 (red). Cell nuclei are stained in blue.
UNDERSTANDING PD-L1 EXPRESSION ON TUMOUR CELLS AND TUMOUR-INFILTRATING IMMUNE CELLS MAY IMPACT PERSONALISED CANCER IMMUNOTHERAPY RESEARCH1,5
As a primary immunosuppressive driver, high expression levels of PD-L1 may be an important facilitator for tumour growth and metastasis. PD-L1 has been detected in up to 50% of human cancers, making the PD-L1 pathway a focus of cancer research.1,4-6
The presence of tumour-infiltrating immune cells has also been reported in many of these cancer types.7-21 Because these immune cells can also express PD-L1, the assessment of PD-L1 on tumour cells and tumour-infiltrating immune cells may be an important consideration for cancer immunotherapy research.
|CANCER TYPE||PERCENTAGE POSITIVE
FOR PD-L1 EXPRESSION1*
|PRESENCE OF TUMOUR-
|Non-small cell lung cancer||35%–95%||9|
|Renal cell carcinoma||15%–24%||20|
- *Table modified according to Chen DS, et al, a review of current literature on PD-L1 expression. 1
- † Percentage of PD-L1 expression is unknown.
- ‡ Includes peripheral T cell lymphomas, diffuse large cell lymphoma, or small lymphocytic lymphoma.
PD-L1 IS A POTENTIAL PREDICTIVE BIOMARKER UNDER INVESTIGATION
Based on clinical studies, PD-L1 expression has been associated with response to PD-L1/PD-1 inhibition, suggesting that cancers with high PD-L1 expression are more likely to respond to immunotherapies that target the PD-L1 pathway.1,6
Roche is actively investigating PD-L1 as a potential predictive biomarker in cancer research and is committed to pursuing the potential of personalised cancer immunotherapy for cancer patients.