Conversely, primary prostate cancers (PCa) have been reported to express low levels of REG4 mRNA, whereas the majority of metastatic PCa tumors expressed high levels [19], and REG4 expression has been associated with lymph node metastasis, recurrence of liver metastasis and tumor stage in colorectal carcinoma [7, 20]. This evidence concerns the gene REG4 and metastatic malignant neoplasm in the lymph nodes.