Dados do Trabalho

Título

Histopathological evaluation of melanoma in the pinna of the ear of C57BL-6 mice, locally treated with Bacillus Calmette-Guérin (BCG).

Introdução

Cutaneous melanoma represents only less than 5% of all common skin cancers, with high lethality. For this reason, alternatives for treatment are being studied. BCG is an alternative that can help in the treatment of neoplasms. BCG was initially developed in its attenuated form for vaccination against tuberculosis and is still described as being responsible for the non-specific increase in the activity of the immune system against tumors.

Objetivo (s)

This work aims to histologically evaluate the changes that BCG causes in the microenvironment of the Melanoma tumor.

Material e Métodos

Tumor growth and survival were assessed in C57BL/6 mice inoculated with B16F0 melanoma cells in the ear's pinna. After 10 days, BCG was injected in vivo. Animals received 5x104 B16F0 in the ear (i.e.), and BCG was injected (1x107 organisms) in situ. Other groups that received the BCG vaccine alone or not were studied (intact control group). For histological evaluation, sections of the pinna containing tumors were processed and stained with HE for qualitative and quantitative analysis.

Resultados e Conclusão

Quantitative and qualitative assessments of points 11, 18, and 21 of the tumor development kinetics showed that the animals in the B16F0+BCG group had a greater inflammatory infiltrate, lower percentage of necrosis, less desmoplastic reaction, and less muscular tumor infiltration. This same group also had more prolonged survival and better tumor containment when compared to the B16F0 group.
Conclusions: Animals with a tumor receiving BCG (B16F0+BCG) had a more significant infiltration of inflammatory cells and less necrosis, desmoplastic reaction, and muscular tumor infiltration. Additionally, they had increased survival and better in situ tumor containment.

Palavras-chave

Melanoma, BCG, inflammatory infiltrate

Agradecimentos

CNPq, CAPES