Surprisingly, SMPD1 and 3 were overexpressed in cancerous tissues of female SCC compared to male SCC (Supplementary Figure S7B,F; B. Cancer SMPD1 mean expression: male 0.634 and female 0.692 p = 0.00047; F. Cancer SMPD3 mean expression: male −0.164 and female −0.0811 p = 0.0081), implying that sphingomyelin hydrolysis was not blocked in female SCC. This evidence concerns the gene SMPD1 and cancer.