TY - JOUR
T1 - The Multiple Faces of Programmed Cell Death Ligand 1 Expression in Malignant and Nonmalignant Cells
AU - Parra, Edwin R.
AU - Villalobos, Pamela
AU - Rodriguez-Canales, Jaime
N1 - Funding Information:
Supported in part by a Department of Defence PROSPECT grant (W81XWH-07-1-0306), The University of Texas Lung Specialized Programs of Research Excellence grant (P50CA70907), MD Ander-son’s Institutional Tissue Bank Award (2P30CA016672) from the National Cancer Institute, Lung Cancer Moon Shot projects (P30 CA01667), SPORE grant (5P50CA070907-18), CPRIT grant (MIRA-RP160688) and National Counsel of Technological and Scientific Development of the Ministry of Science, Technology and Innovation of Brazil (P246042/2012-5).
Publisher Copyright:
© 2019 Wolters Kluwer Health, Inc. All rights reserved.
PY - 2019/4/1
Y1 - 2019/4/1
N2 - Preliminary data suggest that tumor expression of programmed cell death ligand 1 (PD-L1) protein in human cancers, as determined by immunohistochemistry in formalin-fixed, paraffin-embedded tissue samples, may predict clinical response to anti-PD-1/PD-L1 therapy. PD-L1 is not a specific tumor marker and its expression is also observed in various nonmalignant cells, such as macrophages and lymphocytes, causing confusion in immunohistochemistry analysis when these inflammatory cells are overlapping with tumors cells. The aim of the current study was to examine PD-L1 expression in formalin-fixed, paraffin-embedded malignant and nonmalignant cells from human tumors to establish potential characteristic patterns of PD-L1 expression in tumor tissues. We used a commercial PD-L1 clone (E1L3N) previously validated in our laboratory to characterize PD-L1 expression in surgically resected lung adenocarcinomas, lung squamous cell carcinomas, malignant melanomas, renal cell carcinomas, hepatocellular carcinomas, and ductal breast carcinomas. We observed different patterns of PD-L1 expression by malignant cells and nonmalignant cells as membrane, cytoplasmic, and nuclear expression. The distribution of expression was variable including the entire malignant cells population, heterogonous with random distribution, peripheral distribution, minimal expression by few cells and negative expression. Similar, nonmalignant cells showed randomly and peripherally distribution through the tumors. We concluded that the PD-L1 cell protein expression patterns and distributions are variable and differ between resected tumor specimens. The expression and distribution pattern described here provide a useful knowledgment of PD-L1 expression in tumor samples.
AB - Preliminary data suggest that tumor expression of programmed cell death ligand 1 (PD-L1) protein in human cancers, as determined by immunohistochemistry in formalin-fixed, paraffin-embedded tissue samples, may predict clinical response to anti-PD-1/PD-L1 therapy. PD-L1 is not a specific tumor marker and its expression is also observed in various nonmalignant cells, such as macrophages and lymphocytes, causing confusion in immunohistochemistry analysis when these inflammatory cells are overlapping with tumors cells. The aim of the current study was to examine PD-L1 expression in formalin-fixed, paraffin-embedded malignant and nonmalignant cells from human tumors to establish potential characteristic patterns of PD-L1 expression in tumor tissues. We used a commercial PD-L1 clone (E1L3N) previously validated in our laboratory to characterize PD-L1 expression in surgically resected lung adenocarcinomas, lung squamous cell carcinomas, malignant melanomas, renal cell carcinomas, hepatocellular carcinomas, and ductal breast carcinomas. We observed different patterns of PD-L1 expression by malignant cells and nonmalignant cells as membrane, cytoplasmic, and nuclear expression. The distribution of expression was variable including the entire malignant cells population, heterogonous with random distribution, peripheral distribution, minimal expression by few cells and negative expression. Similar, nonmalignant cells showed randomly and peripherally distribution through the tumors. We concluded that the PD-L1 cell protein expression patterns and distributions are variable and differ between resected tumor specimens. The expression and distribution pattern described here provide a useful knowledgment of PD-L1 expression in tumor samples.
KW - Immunohistochemistry
KW - PD-L1
KW - Patterns
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U2 - 10.1097/PAI.0000000000000602
DO - 10.1097/PAI.0000000000000602
M3 - Article
C2 - 29135534
AN - SCOPUS:85060681486
SN - 1541-2016
VL - 27
SP - 287
EP - 294
JO - Applied Immunohistochemistry and Molecular Morphology
JF - Applied Immunohistochemistry and Molecular Morphology
IS - 4
ER -