Dataset Information

PD-L1 assessment in pediatric rhabdomyosarcoma: a pilot study.

ABSTRACT: BACKGROUND:Rhabdomyosarcomas (RMSs) are the most frequent soft tissue sarcoma in children and adolescents, defined by skeletal muscle differentiation and the status of FOXO1 fusions. In pediatric malignancies, in particular RMS, scant and controversial observations are reported about PD-L1 expression as a putative biomarker and few immune checkpoint clinical trials are conducted. METHODS:PD-L1 assessment was evaluated by immunohistochemistry (IHC) utilizing two anti-PDL1 antibodies, in a pilot cohort of 25 RMS. Results were confirmed in primary and commercial RMS cell lines by cytofluorimetric analysis and IHC. RESULTS:PD-L1 expression was detectable, by both anti-PD-L1 antibodies, in the immune contexture of immune cells infiltrating and/or surrounding the tumor, in 15/25 (60%) RMS, while absent expression was observed in neoplastic cells. Flow cytometry analysis and PD-L1 IHC of commercial and primary RMS cell lines confirmed a very small percentage of PD-L1 positive-tumor cells, under the detection limits of conventional IHC. Interestingly, increased PD-L1 expression was observed in the immune contexture of 4 RMS cases post chemotherapy compared to their matched pre-treatment samples. CONCLUSION:Here we identify a peculiar pattern of PD-L1 expression in our RMS series with scanty positive-tumor cells detected by flow cytometry, and recurrent expression in the immune cells surrounding or infiltrating the tumor burden.

SUBMITTER: Bertolini G

PROVIDER: S-EPMC6001160 | biostudies-literature | 2018 Jun

REPOSITORIES: biostudies-literature

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PD-L1 assessment in pediatric rhabdomyosarcoma: a pilot study.

Bertolini Giulia G Bergamaschi Luca L Ferrari Andrea A Renne Salvatore L SL Collini Paola P Gardelli Cecilia C Barisella Marta M Centonze Giovanni G Chiaravalli Stefano S Paolino Cinzia C Milione Massimo M Massimino Maura M Casanova Michela M Gasparini Patrizia P

BMC cancer 20180613 1

<h4>Background</h4>Rhabdomyosarcomas (RMSs) are the most frequent soft tissue sarcoma in children and adolescents, defined by skeletal muscle differentiation and the status of FOXO1 fusions. In pediatric malignancies, in particular RMS, scant and controversial observations are reported about PD-L1 expression as a putative biomarker and few immune checkpoint clinical trials are conducted.<h4>Methods</h4>PD-L1 assessment was evaluated by immunohistochemistry (IHC) utilizing two anti-PDL1 antibodie ...[more]

PMID: 29898687

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Dataset Information

PD-L1 assessment in pediatric rhabdomyosarcoma: a pilot study.

Publications

PD-L1 assessment in pediatric rhabdomyosarcoma: a pilot study.

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