Neoplastic Alterations Induced in Mammalian Skin Following Mancozeb Exposure UsingIn VivoandIn VitroModels

Abstract

Mancozeb, ethylene(bis)dithiocarbamate fungicides, has been well documented in the literature as a multipotent carcinogen, but the underlying mechanism remains unrevealed. Thus, mancozeb has been selected in this study with the objective to decipher the molecular mechanism that culminates in carcinogenesis. We employed two-dimensional gel electrophoresis and mass spectrometry to generate a comparative proteome profile of control and mancozeb (200 mg/kg body weight) exposed mouse skin. Although many differentially expressed proteins were found, among them, two significantly upregulated proteins, namely, S100A6 (Calcyclin) and S100A9 (Calgranulin-B), are known markers of keratinocyte differentiation and proliferation, which suggested their role in mancozeb-induced neoplastic alterations. Therefore, we verified these alterations in the human system by using HaCaT cells as an in vitro model for human skin keratinocyte carcinogenesis. Upregulation of these two proteins upon mancozeb (0.5 μg/mL) exposure in HaCaT cells indicated its neoplastic potential in human skin also. This potential was confirmed by increase in number of colonies in colony formation and anchorage-independent growth assays. Modulation of S100A6/S100A9 targets, elevated phosphorylation of extracellular signal regulated kinase (ERK1/2), Elk1, nuclear factor- kappa B and cell division cycle 25 C phosphatase, and cyclin D1 and cyclooxygenase-2 upregulation was seen. In addition, PD98059 (ERK1/2 inhibitor) reduced cell proliferation induced by mancozeb, confirming the involvement of ERK1/2 signaling. Conclusively, we herein present the first report asserting that the mechanism involving S100A6 and S100A9 regulated ERK1/2 signaling underlies the mancozeb-induced neoplastic potential in human skin.

Emptying of Intracellular Calcium Pool and Oxidative Stress Imbalance Are Associated with the Glyphosate-Induced Proliferation in Human Skin Keratinocytes HaCaT Cells

“…In the past, we studied alterations in global protein expression using samples of mouse skin treated with glyphosate and the tumor promoter TPA, which is a potent activator of keratinocyte proliferation [46], epidermal hyperplasia and dermal inflammation [47], and we found strong upregulation of S100A6 and S100A9 [30]. More recently, strong upregulation of both proteins was also reported by us in HaCaT cells upon mancozeb (fungicide) exposure [48]. Numerous recent reviews focused on the extracellular function of S100A6/A9 and its presumed impact on pathological processes such as acute and chronic inflammations or carcinogenesis [49–51].…”

Squamous Cell Carcinoma: Biomarkers and Potential Therapeutic Targets

“…The same approach in human keratinocyte carcinogenesis model with HaCaT cells revealed that upregulation of S100A6 and S100A9 confirms the neoplastic potential of Mancozeb. The authors conclude that S100A6 and S100A9 modulate the ERK1/2 signaling pathway underlying in this way the Mancozeb-induced neoplastic potential in human skin [24], and thus, a certain proteome milieu prescribe keratinocyte behavior in a chemically triggered carcinogenesis.…”

Pesticides and cancer: Insights into toxicoproteomic-based findings

“…However the group of Carreon and co-workers [43] nullified the chance of occurrence of intracranial gliomas in women farmers due to pesticide exposure although they also clarify the reason may be the women are less exposed to pesticides than man farmers. Studies from our laboratory have also shown the carcinogenic potential of many pesticides by using animal models and cell culture studies [44][45][46][47][48]. Despite these reports, the mechanism triggering the induction of carcinogenesis by pesticides is still unknown.…”

“…The level of 2 proteins (S100A6 and S100A9) was significantly up regulated in the mancozeb exposed mouse skin and later found to be higher in mancozeb-exposed human keratinocytes HaCaT cells. These proteins are known markers of keratinocyte differentiation and proliferation, and suggested their possible role in mancozebinduced neoplastic alterations in mammalian skin system [44].…”