Serum Cellular Apoptosis Susceptibility Protein for Cancer Diagnosis

Tumor invasion and metastasis are the main cause of cancer mortality. CSE1L/CAS, the cellular apoptosis susceptibility protein, is the human homologue of the yeast chromosome segregation gene product, CSE1. Pathological studies show that CSE1L is highly expressed in various cancers, such as lung cancer, breast cancer, liver cancer, ovarian cancer, endometrial carcinomas, skin cancer, colorectal cancer, lymphomas, prostate cancers, nasopharyngeal carcinomas, medulloblastomas, and glioblastomas. The CSE1L gene is located on chromosome 20q13, a region that frequently harbors amplifications that correlate with cancer aggression. Experimental studies have shown that CSE1L regulates the invasion of cancer cells in vitro and in animal metastasis models. The results of our recent studies have revealed that CSE1L is a secretory protein present in sera from cancer patients. Significantly, there is a higher prevalence of secretory CSE1L in sera of patients with metastatic cancer. Here, we discuss the potential of CSE1L as a serum marker for the diagnosis of cancer.