Establishment and Characterization of Primary Cell Lines of Squamous Cell Carcinoma of the Penis and its Metastasis

Purpose: We established cell lines from penile squamous cell carcinoma and its lymph node metastasis, and investigated the role of chemokines, chemokine receptors and podoplanin in cancer progression. Materials and Methods: Tumor specimen of primary tumors, and lymph node and distant metastases were cultured in vitro and xenotransplanted in SCID beige mice. Specimens were analyzed by hematoxylin and eosin staining, and immunohistochemistry. Comparative screening for chemokines, chemokine receptors and podoplanin was done by polymerase chain reaction, fluorescence activated cell sorting and enzyme-linked immunosorbent assay. Results: We established 2 cell lines from a primary tumor and its corresponding lymph node metastasis, respectively. Heterotopic xenotransplantation revealed reliable tumor growth in vivo. Morphological and immunohistological analysis showed comparable features for human tumors, cell lines in vitro and xenotransplanted tumors in mice regarding the primary tumor and metastasis. Comprehensive analysis of chemokines and chemokine receptors in the metastasis derived cell line and in the cell line originating from the primary tumor revealed the most pronounced changes for CXCL14. This pattern was confirmed on the protein level. Comparative analysis of podoplanin showed marked down-regulation in the metastatic variant on the mRNA and protein levels. Conclusions: To our knowledge we established the first pair of cell lines of a human primary penile tumor and the corresponding lymph node metastasis. These cell lines offer unique possibilities for further comparative functional investigations in in vitro and in vivo settings. They enable studies of new potential therapeutic agents and other assays to better understand the molecular mechanisms of penile cancer progression.