Fig 2: Immunohistochemistry of MM. Immunohistochemical staining for ASIC1, ASIC2, TRPV1 and TRPV4 in MM tissue. (a–d) Histochemical H&E staining, (e–h) immunohistochemical staining, inserted smaller pictures represent a two times larger perspective. Scale bars represent 200 μm. (a–h) Patient 30.

Fig 3: Summary of standard immunohistochemical and TMA score results for ASIC1, ASIC2, TRPV1 and TRPV4 on (a) SCC, (b) BCC, (c) NCN and (d) MM. ++/green bar: strong positive staining with >80% of cells positive and/or staining intensity is high; +/blue bar: 20–80% of cells show a weak positive/partial positive reaction; −/red bar: <20% of cells with weak staining (=negative reaction). NCN and MM are subdivided into epidermal and dermal portions. Numbers in bars represent the occurrence of the particular score. Superscript numbers give additional information: (1) some samples showed a decreasing expression in deeper dermal tumor tissue. (2) Single tumor cells are stained strong positive, others appear negative, resulting in an overall partial positive score (+). Overall trend is indicated by a green, white or red box with the number of samples investigated; green box: general positive reactions; white box: mixed reactions; red box: mainly negative reactions. For additional information on the individual TMA scores, see Supplementary Tables S2–S5.

Fig 4: Immunohistochemistry of SCC. Immunohistochemical staining for ASIC1, ASIC2, TRPV1 and TRPV4 in SCC tissue. (a–d) H&E staining, (e–h) immunohistochemical staining, inserted smaller pictures represent a two times larger perspective. Scale bars represent 200 μm. (a–h) Patient 8. This SCC shows no expression of ASIC2, only some peritumoral lymphocytes appear positive. The tumor cells show a weak, positive expression of TRPV1 and TRPV4. ASIC1 is expressed strongly on tumor cells. For more stainings of other SCCs, see Supplementary Figures S1–S3.

Fig 5: Immunohistochemistry of BCC. Immunohistochemical staining for ASIC1, ASIC2, TRPV1 and TRPV4 in BCC tissue. (a–d) H&E staining, (e–h) immunohistochemical staining, inserted smaller pictures give an overview. Scale bars represent 200 μm. (a–h) Patient 10. This BCC shows a strong expression of ASIC1 and TRPV1. The expression of TRPV4 is weak and positive, but this BCC shows no expression of ASIC2. For more stainings of other BCCs, see Supplementary Figures S4–S7.