Journal: Scientific Reports

Article Title: Evidence for a non-stochastic two-field hypothesis for persistent skin cancer risk

doi: 10.1038/s41598-020-75864-2

Figure Lengend Snippet: Persistent hyperemic foci exhibit evidence of dermal senescence. ( A – E ) Dermal cells in areas of high Hgb content exhibit a heterochromatin pattern of DAPI staining. After excision of skin from mice treated with and without UV at 2 and 20 weeks after stopping UV treatments, the sections were stained with DAPI to better demonstrate nuclear morphology. Nuclei of dermal cells showing a heterochromatin staining pattern are shown by white arrows while nuclei exhibiting a euchromatin pattern of DAPI staining are shown by yellow arrows. The hatched white line outlines the epidermal-dermal junction. The white scale bar represents 50 µm. ( A ) Skin from an area of low Hgb content 2 weeks after stopping UV treatments. ( B ) Skin from an area of high Hgb content 2 weeks after stopping UV treatments. ( C ) Control non-UV treated skin. ( D ) Skin from an area of low Hgb content 20 weeks after stopping UV. ( E ) Skin from an area of high Hgb content 20 weeks after stopping UV. (F – J ) Representative photomigrographs of skin following immunolabeling with anti-p16 INK4a antibodies. ( F ) Control non-UV treated epidermis. ( G , H ) Skin excised 2 weeks after stopping UV treatments from an area of low Hgb content ( G ) or from an area of high Hgb content ( H ). ( I , J ) Skin excised from a low Hgb area ( I ) or a high Hgb area ( J ) at 20 weeks after stopping UV treatments. Black arrows in ( H , J ) show dermal cells with enlarged nuclei labeling positive for p16 INK4a . The black scale bars represent 100 µm. ( K ) HP1γ + dermal cells are increased in hyperemic areas at both 2 and 20 weeks after stopping UV treatments. Immunofluorescent (IF) labeling of formalin-fixed skin sections was performed using anti-HP1γ and anti-pancytokeratin (CK) antibody. The data depicts the % of dermal cells positive for HP1γ nuclear labeling. ( L ) Dermal cells positive for nuclear γH2AX are also increased in hyperemic areas only at 2 and 20 weeks post-UV. IF was performed for both nuclear γH2AX immunolabeling and CK. The data shown is the percentage of γH2AX + dermal cells relative to all CK negative cells. (ns = non-significant; ** = p < 0.01; *** = p < 0.001).

Article Snippet: Immunofluorescent staining of formalin-fixed paraffin-embedded mouse skin following heat-induced antigen retrieval was performed using the following antibodies: HP1γ (Cbx3) immunolabeling was done using rabbit anti-Cbx3 (1:250, Cat#IHC-00204, Bethyl Laboratories). γH2AX immunolabeling was done using monoclonal rabbit anti-γH2AX (1:100, Bethyl Laboratories, Cat#A700-053).

Techniques: Staining, Control, Immunolabeling, Labeling