Investigation of the expression of pro-angiogenic markers in cutaneous tumours in vivo and in vitro

Abstract

Cutaneous tumours are common types of cancers that develop from the skin and account for 40% of the cases worldwide. In particular, melanomas and cutaneous haemangiomas are commonly occurring skin tumours that are characterised by aggressive growth. Angiogenesis, the development of cutaneous tumours such as haemangioma and melanoma, has been associated with angiogenesis the formation of new blood vessels from existing vasculature - promoting tumour proliferation, survival, and metastasis in the case of melanoma. As a result, there is a need to identify angiogenic markers as a tool that could systematically disrupt the vessel formation process.

This study aimed to investigate markers of angiogenesis in cutaneous tumour cells and biopsies. Endothelial cells cultured in different medium conditions (normal, melanoma-conditioned, and serum-free) were analysed for growth and cell morphology. Vascular endothelial growth factor-A (VEGF-A), basic fibroblast growth factor and platelet-derived growth factor-BB (PDGF-BB) were quantified in an ELISA kit to determine their expression level as angiogenic biomolecular markers, employing melanoma B16-F10 cell lines. Formalin-fixed haemangioma biopsy tissues were investigated for the presence of EC using IHC and a light microscope. The expression of Bcl-2 and VEGF-R were also analysed following immunoreactivity against appropriate antibodies.

In this study, a time-dependent cell growth assay was employed, using crystal violet as the investigative tool. The results of this study demonstrated that the cells grown in a melanoma-conditioned environment induced a proliferative effect while those incubated with serum-free medium exhibited cell growth inhibition. When cells were treated with a dose-dependent Nocodazole, cell growth inhibition was also initiated. The cells showed a healthy spindle-like shape with well-defined nucleoli in both conditions. No morphological difference existed between the cell populations cultured in a different medium. High expression levels of VEGF-A and bFGF in melanoma B16-F10 cells were identified and significantly (p < 0.05) associated with the progression of the disease. Although no scientific significance was found for PDGF in the cutaneous tumour cells, their expression was depicted. Dilated vessels with red blood cells were observed in tumour tissues of haemangioma. While the expression of Bcl-2 in cutaneous tumour tissues was barely expressed, the antibodies against VEGF-R strongly depicted the molecular expression.

In conclusion, the collectively identified molecular markers in vivo and in vitro serve as potential prognostic markers that could enable clinicians to diagnose the disease early and lower its burden through revolutionised anti-angiogenic therapy.