CD37 and cholangiocarcinoma: We observed the expression profiling of CD37 in different types of cancers, and CD37 expression is higher in breast invasive carcinoma, cervical squamous cell carcinoma and endocervical adenocarcinoma, cholangiocarcinoma and DLBCL, but lower in adrenocortical carcinoma, bladder urothelial carcinoma, colon adenocarcinoma compared with normal adjacent tissues (Figure 1A).