Tumour-associated Angiogenesis and Intermediate Blood Vessels in Renal Cell Carcinoma

Abstract

Background/Aim: Renal cell carcinoma is strongly vascularized, and formation of new blood vessels is a complex and multi-step process. In this study, we analysed the subtypes of intermediate blood vessels, as shown by double immunohistochemistry. Materials and Methods: Tumour-associated blood vessels were identified by double immunostaining based on CD34 and smooth muscle cell actin. Blood vessels were classified both quantitatively and qualitatively based on the expression of the aforementioned two markers. The main criteria to sub-classify intermediate blood vessels was the presence, distribution, and arrangement of perivascular cells. Results: We described three subtypes of intermediate blood vessels found particularly in the tumour area: Subtype 1 lacked perivascular cells, subtype 2 showed scattered pericytes attached to the vascular wall, and subtype 3 showed a continuous layer of perivascular cells on one side. Conclusion: We describe for the first time three subtypes of renal cell carcinoma-associated intermediate blood vessels, which could be important in prognosis and as potential targets for anti-vascular therapy.

Tumor Microenvironment‐Related Sonodynamic Therapy Mediates Tumor Therapy

“…Hypoxia is a common TME characteristic of solid tumors and is caused by the abnormal structure of tumor blood vessels and the imbalance between O 2 transport and O 2 consumption. [62,63] Under the influence of O 2 diffusion distance, hypoxic and necrotic areas will be formed at a distance of more than 100 μm from the blood vessels inside the tumor. [64] Tumor cell hypoxia mainly includes three mechanisms: chronic or diffusion-limited hypoxia, acute or perfusion-limited hypoxia, and anemia-related hypoxia.…”

Caracterização do índice de cobertura por pericitos em neoplasias mamárias caninas e seu papel como fator prognóstico

“…Estes dados corroboraram, em parte, um estudo epidemiológico chinês para neoplasias mamárias caninas publicado porZheng et al, (2022) cujas porcentagens para os diferentes graus foram de 41%, 32% e 23% respectivamente.Ao avaliarmos os dados dos dois estudos, notamos que há mais neoplasias de baixo grau e menos neoplasias de alto grau em ambos. Entretanto, nosso número amostral é sensivelmente menor (78 casos versus 504 casos).Embora o tipo histológico seja um fator prognóstico independente para as neoplasias mamárias e que há diferente sobrevida entre as diferentes neoplasias(RASOTTO et al, 2017) nosso estudo não correlacionou estes subtipos ao PCI a fim de avaliar uma possível variabilidade intra-tumoral. Tal fato se deve à pouca variabilidade entre os tipos tumorais e ao número diminuto das amostras estudadas na nossa investigação.…”