Inflammation: A key process in skin tumorigenesis (Review)

Abstract

The extremely delicate shift from an inflammatory process to tumorigenesis is a field of major scientific interest. While the inflammation induced by environmental agents has well known underlying mechanisms, less is known concerning the oncogenic changes that follow an inflammatory chronic status in the tissue microenvironment that can lead to pro-tumorigenic processes. Regardless of the origin of the environmental factors, the maintenance of an inflammatory microenvironment is a clear condition that favors tumorigenesis. Inflammation sustains the proliferation and survival of malignant transformed cells, can promote angiogenesis and metastatic processes, can negatively regulate the antitumoral adaptive and innate immune responses and may alter the efficacy of therapeutic agents. There is an abundance of studies focusing on molecular pathways that trigger inflammation-mediated tumorigenesis, and these data have revealed a series of biomarkers that can improve the diagnosis and prognosis in oncology. In skin there is a clear connection between tissue destruction, inflammation and tumor onset. Inflammation is a self-limiting process in normal physiological conditions, while tumor is a constitutive process activating new pro-tumor mechanisms. Among skin cancers, the most commonly diagnosed skin cancers, squamous cell carcinoma and basal cell carcinoma (BCC) have important inflammatory components. The most aggressive skin cancer, melanoma, is extensively research in regards to the new context of novel developed immune-therapies. In skin cancers, inflammatory markers can find their place in the biomarker set for improvement of diagnosis and prognosis.

The Role of Beta HPV Types and HPV-Associated Inflammatory Processes in Cutaneous Squamous Cell Carcinoma

“…Thus, TLR-4 expression is higher in actinic keratoses compared to normal skin and in cSCC compared to actinic keratoses. It has been shown that the inhibition of their function reduces the harmful effects of UV on the keratinocytes [5].…”

Statistics of Canine Skin Tumors in Korea during 2005-2018

“…However, as ulceration and typical pyogranulomatous inflammation was prominent in majority of histological sections with reported clinical signs of inflammation, the greatest possibility seems to be due to self-trauma. However, as inflammation could promote tumorigenesis and tumor progression (Hensler and Mueller, 2013;Neagu et al, 2019), it might suggest the correlation between skin tumorigenesis and inflammation in canine species, as other kinds of cancer in dogs (Morrison, 2011). In addition, this study provides evidence that a rapid or progressive increase in mass size or multiple nodules throughout the body can be indirect indicators for tumor.…”

Fine Needle Aspiration Cytology (FNAC) for Chinese Patients With Acral and Cutaneous Melanoma: Accuracy and Safety Analysis From a Single Institution

“…Inflammatory cells can induce and help maintain tumor angiogenesis by releasing inflammatory factors, stimulating tumor cell proliferation and thus supporting their metastasis and spread and promoting tumor tissue infiltration. Inflammatory biomarkers were found to be associated with the prognosis of patients with melanoma (31)(32)(33)(34). FNAC is mainly used as a diagnostic tool and cannot completely remove tumors.…”