Related Experiment Video
Updated: Feb 16, 2026

Multiplexed Immunofluorescence Analysis and Quantification of Intratumoral PD-1+ Tim-3+ CD8+ T Cells
Published on: February 8, 2018
Programmed death-ligand 1 expression correlates with diminished CD8+ T cell infiltration and predicts poor prognosis
Yu-Jie Zhao1, Wei-Peng Sun2, Jian-Hong Peng1
1Department of Colorectal Surgery, State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Sun Yat-sen University Cancer Center.
Objective:
Increased expression of programmed death-ligand 1 (PD-L1) on tumor cells can be found in various malignancies; however, very limited information is known about its role in anal squamous cell carcinoma (ASCC). This study explored PD-L1 expression in ASCC patients and its association with patients' clinicopathological features, CD8+ T cell infiltration, and prognosis.
Methods:
Formalin-fixed paraffin-embedded tumor samples from 26 patients with ASCC were retrieved. The levels of PD-L1 expression on the membrane of both tumor cells and tumor-infiltrating mononuclear cells (TIMCs) were evaluated by immunohistochemistry. CD8+ T cell densities, both within tumors and at the tumor-stromal interface, were also analyzed. Baseline clinicopathological characteristics, human papilloma virus (HPV) status, and outcome data correlated with PD-L1-positive staining.
Results:
PD-L1 expression on tumor cells and TIMCs was observed in 46% and 50% of patients, respectively. Nineteen patients (73%) were HPV positive, with 7 showing PD-L1-positive staining on tumor cells and 9 showing PD-L1-positive staining on TIMCs. Increasing CD8+ density within tumors, but not immune stroma, was significantly associated with decreased PD-L1 expression by both tumor cells and TIMCs (P=0.0043 and P=0.0007). Patients with negative PD-L1 expression had significantly better progression-free survival (P=0.038 and P=0.0443) and a non-statistically significant trend toward longer overall survival (P=0.0882 and P=0.1222) compared with patients with positive PD-L1 expression.
Conclusion:
PD-L1 is widely expressed on the membrane of tumor cells and TIMCs in ASCCs. Its negative impact on prognosis may be due to the diminished CD8+ T cell infiltration within tumors.
More Related Videos
07:43Four-color Fluorescence Immunohistochemistry of T-cell Subpopulations in Archival Formalin-fixed, Paraffin-embedded Human Oropharyngeal Squamous Cell Carcinoma Samples
Published on: July 29, 2017
09:06Development of a 68Gallium-Labeled D-Peptide PET Tracer for Imaging Programmed Death-Ligand 1 Expression
Published on: February 3, 2023
Related Concept Videos
Autophagic Cell Death
Autophagy and Apoptosis
Autophagy can activate apoptosis. In normal conditions, the autophagy activating protein Beclin-1 and...
Overview of Cell Death
Cell death was observed in the early 19th century, but there was no experimental evidence to prove it. In 1842, Carl Vogt first discovered cell death in a metamorphic toad; however, it was not termed ‘cell death.’ Scientists discovered different cell death pathways only in the...
Predicting Products: SN1 vs. SN2
With increased substitution on the alkyl halide,...
Cell Specific Gene Expression
Cell Specific Gene Expression
Metal-Ligand Bonds
In these complexes, transition metals form coordinate covalent bonds, a kind of Lewis acid-base interaction in which both of the electrons in the bond are contributed by a donor (Lewis base) to an electron acceptor (Lewis acid). The Lewis acid in...