Data documento
06/05/2024

Título
Digital expression profile of immune checkpoint genes in medulloblastomas identifies CD24 and CD276 as putative immunotherapy targets

Autor(es)
Marques R.F. - Moreno D.A. - da Silva L. - Leal L.F. - de Paula F.E. - Santana I. - Teixeira G. - Saggioro F. - Neder L. - Junior C.A. - Mançano B. - Reis R.M.

Palavras chave
immune checkpoints - immune profile - immunotherapy - medulloblastoma - nCounter mRNA expression assay

Resumo
Introduction: Medulloblastoma is the most common and lethal pediatric malignant brain tumor. It comprises four main molecular subgroups: WNT-activated, SHH-activated, Group 3, and Group 4. Medulloblastoma treatment is surgical resection, craniospinal radiation, and chemotherapy. However, many patients do not respond to therapy, and most suffer severe side effects. Cancer immunotherapy targeting immune checkpoints (IC) (PD-1, PD-L1, and CTLA4) has been getting disappointing outcomes in brain tumors. Nevertheless, other less explored immune checkpoints may be promising candidates for medulloblastoma therapy. Objectives: In the present study, we aimed to characterize the expression profile of 19 immune checkpoints in medulloblastoma. Methods: We analyzed 88 formalin-fixed paraffin-embedded medulloblastomas previously classified for each molecular subgroup and three non-tumoral brain tissue. mRNA levels of 19 immune checkpoint-related genes were quantified using the nCounter (PanCancer Immune Profiling Panel) assay. Further in silico analysis was performed in two larger public microarray datasets, one of which enabled comparisons between tumoral and non-tumoral tissues. Immunohistochemistry of PD-L1 was performed in a subset of cases. Microsatellite instability was also molecularly analyzed. Results: We observed an absence of expression of the canonic ICs, namely PDCD1 (PD-1), CD274 (PD-L1), and CTLA4, as well as CD80, CD86, BTLA, IDO1, CD48, TNFSF14, CD160, CEACAM1, and CD244. PD-L1 protein expression was also practically absent. We found higher mRNA levels of CD24, CD47, CD276 (B7-H3), and PVR, and lower mRNA levels of HAVCR2, LAG3, and TIGIT genes, with significant differences across the four molecular subgroups. Compared to the non-tumor tissues, the expression levels of CD276 in all subgroups and CD24 in SHH, Group 3, and Group 4 subgroups are significantly higher. The in silico analysis confirmed the expression profile found in the Brazilian cohort, including the lower/absent expression of the canonic ICs. Moreover, it confirmed the overexpression of CD24 and CD276 in medulloblastomas compared with the non-tumor tissue. Additionally, CD276 and CD24 high levels were associated with worse survival. Conclusion: These results highlight the low or absence of mRNA levels of the canonic targetable ICs in medulloblastomas. Importantly, the analysis revealed overexpression of CD24 and CD276, which can constitute prognostic biomarkers and attractive immunotherapy targets for medulloblastomas.

Citação
Marques RF, Moreno DA, da Silva L, Leal LF, de Paula FE, Santana I, Teixeira G, Saggioro F, Neder L, Junior CA, Mançano B, Reis RM. Digital expression profile of immune checkpoint genes in medulloblastomas identifies CD24 and CD276 as putative immunotherapy targets. Front Immunol. 2023 Feb 7;14:1062856. doi: 10.3389/fimmu.2023.1062856. PMID: 36825029; PMCID: PMC9941636.

Data documento
26/04/2024

Título
PD L1 expression and microsatellite instability (MSI) in cancer of unknown primary site

Autor(es)
JÚNIOR, João Neif Antonio - PRETO, Daniel D.’Almeida - LAZARINI, Maria Eduarda Zanatta Neder - LIMA, Marcos Alves de - BONATELLI, Murilo - BERARDINELLI, Gustavo Noriz - SILVA, Vinicius Duval da - PINHEIRO, Céline - REIS, Rui Manuel, CÁRCANO, Flavio Mavignier -

Palavras chave
Neoplasms - Unknown primary - Microsatellite instability - Immune checkpoint proteins - Immunotherapy

Resumo
Background Cancer of unknown primary site (CUP) is a heterogeneous group of tumors for which the origin remains unknown. Clinical outcomes might be influenced by regulatory processes in its microenvironment. Microsatellite instability (MSI) is a predictive biomarker for cancer immunotherapy and its status, as well as co-occurrence with PD-L1 expression, is poorly evaluated. We aim to evaluate the expression of PD-L1 and the status of MSI in CUP and their possible associations with clinical–pathological features. Methods The combined positive score (CPS) PD-L1 expression was evaluated by immunohistochemistry. MSI status was assessed using a hexa-plex marker panel by polymerase chain reaction followed by fragment analysis. Results Among the 166 cases, MSI analysis was conclusive in 120, with two cases being MSI positive (1.6%). PD-L1 expression was positive in 18.3% of 109 feasible cases. PD-L1 expression was significantly associated with non-visceral metastasis and a dominance of nodal metastasis. The median overall survival (mOS) was 3.7 (95% CI 1.6–5.8) months and patients who expressed PD-L1 achieved a better mOS compared to those who did not express PD-L1 (18.7 versus 3.0 months, p-value: < .001). ECOG-PS equal to or more than two and PD-L1 expression were independent prognostic factors in multivariate analysis (2.37 and 0.42, respectively). Conclusion PD-L1 is expressed in a subset (1/5) of patients with CUP and associated with improved overall survival, while MSI is a rare event. There is a need to explore better the tumor microenvironment as well as the role of immunotherapy to change such a bad clinical outcome.

Citação
Junior JNA, Preto DD, Lazarini MEZN, de Lima MA, Bonatelli M, Berardinelli GN, da Silva VD, Pinheiro C, Reis RM, Cárcano FM. PD-L1 expression and microsatellite instability (MSI) in cancer of unknown primary site. Int J Clin Oncol. 2024 Mar 25. doi: 10.1007/s10147-024-02494-3. Epub ahead of print. PMID: 38528294.