PD-L1 expression was significantly associated with poor prognostic factors such as a higher ISUP nucleolar grade (p = 0.01), metastases at diagnosis (p = 0.01), a sarcomatoid component (p = 0.04), overexpression of VEGF (p = 0.006), and cytoplasmic PAR-3 expression (p = 0.01).
Meanwhile, we also confirmed the down-regulation of PD-L1 in osteosarcoma in response to PDT and 3-MA treatment, which significantly inhibited tumor growth in a model of tumor metastasis.
On 27 paired samples, IC1/2/3 score on TCs was homogeneous distributed with 59.3% in primary tumors and metastases, but with a high discordance rate of 44.4% of PD-L1 positivity on ICs.
Here, we determined PD-L1 protein expression by immunohistochemistry using a validated PD-L1-specific antibody (SP263) in a large and representative cohort of primary prostate cancers and prostate cancer metastases.
PD-L1 expression was analyzed using immunohistochemistry (Merck; clone 22C3) in 678 stages I-III NSCLC and 52 paired nodal metastases using tissue microarrays.
PD-L1 expression was analyzed by immunohistochemistry using two different antibodies in primary tumors and paired metastases from 81 melanoma patients treated at a single institution.
PD-L1 expression (clone SP142) was investigated in esophageal adenocarcinomas using tissue microarrays (TMA) from 112 primary resected tumors, preoperative biopsies and full slide sections from a subset of these cases (n = 24), corresponding lymph node (n = 55) and distant metastases (n = 17).
We herein characterize PD-L1 expression in breast cancers across the full range of histomorphologies and investigate its intratumoral heterogeneity and fidelity across primaries and metastases.
Positive PD-L1 expression was found in 13% of primary tumours, 25% of relapses and 48% of metastases and correlated with a high T-cell infiltrate (p = 0.002).
Although there is no difference in infiltrating CD8<sup>+</sup> T cells between UM and CM, a significant decrease in programmed death-1 (PD-1)-positive lymphocytes was observed and lower levels of programmed death ligand-1 (PD-L1) in UM metastases compared with CM metastases.
PD-L1 is frequently expressed in intracranial SFT/HPCs, and diffuse or intense PD-L1 expression might be associated with the early occurrence of extracranial metastases.
Patients with metastatic cancer (<i>n</i> = 198) were analyzed by flow cytometry for DC-HIL or PDL1 expression on blood CD14<sup>+</sup>HLA-DR<sup>no/lo</sup> MDSCs.
<b>Methods:</b> CD163<sup>+</sup> macrophages, CD3<sup>+</sup> T-cells, PD-L1/PD-L2 and HLA class I expression (HCA2, HC10 and β2m) were evaluated using immunohistochemistry in primary tumors (n = 75), local relapses (n = 6) and metastases (n = 19) of 87 LMS patients, as well as in benign leiomyomas (n = 7).
PD-L1 is also expressed on the K7M2 osteosarcoma tumor cell line that establishes metastases in mice, and PD-1 is expressed on tumor-infiltrating CTLs during disease progression.