NUMERO: #20250072

Título: IMMUNOHISTOCHEMICAL STUDY OF THE TUMOR MICROENVIRONMENT IN XENOGRAFT TUMORS DERIVED FROM ORAL SQUAMOUS CELL CARCINOMA

Nome do Apresentador: Mateus José DUTRA

Categoria do Trabalho: Painel de pesquisa científica (PPC)

Área Temática: Oncologia

Resumo: Objective: To compare histological and immunohistochemical findings between donor tumors and patient-derived xenograft (PDX) models of oral squamous cell carcinoma (OSCC). Study design: OSCC samples were collected from five patients, one fragment was processed and embedded in a paraffin block, while another fragment was implanted into mice (PDX0). After tumor growth, the animals were sacrificed, and the tumors were processed and embedded in paraffin blocks. Histological slides with sections were stained with hematoxylin and eosin and subjected to immunohistochemical reactions with antibodies to SMA, CD4, CD8, CD31, CD34, and Ki-67. Results: The histological grade of PDX0 tumors remained the same or decreased in most cases compared to the donor patient's tumor. PDX0 tumors showed higher expression of SMA in stromal fibroblasts and an increased Ki-67 index, while for CD4, CD8, CD31 and CD34 there was a reduction in expression when compared to donor tumors. Conclusion: PDX OSCC tumors maintain histopathological similarity to the original tumors, however, changes in the tumor microenvironment were observed in relation to inflammatory cells and vascularization, when compared to donor tumors. We thank the financial support from FAPESP (process numbers 2016/05710-4, 2022/01257-4, 23/13797-6 and 2024/00600-2).

Autor 1:  Mateus José DUTRA

E-mail 1:  [email protected]

Autor 2:   Brendo Vinicius Rodrigues LOUREDO

E-mail 2:  [email protected]

Autor 3 :  Sebastião Silvério de SOUSA-NETO

E-mail 3:  [email protected]

Autor 4:  Hélen Kaline Farias BEZERRA

E-mail 4:  [email protected]

Autor 5:  Manoela Domingues MARTINS

E-mail 5:  [email protected]

Autor 6:  Pablo Agustin VARGAS

E-mail 6:  [email protected]

Autor 7:  Vivian Petersen WAGNER

E-mail 7:  [email protected]