Lacryglobin in human tears, a potential marker for cancer

Lacryglobin has been identified in human tears. This protein has high seque nce homology to the mammaglobins, proteins upregulated in breast cancer and in breast cancer metastasis. In order to investigate the utility of tear s creening for cancer, tear samples were collected from patients with differe nt types of cancer and compared to controls. Tear samples were taken from f ive controls and eight breast, six lung, five colon, one prostate and three ovary cancer patients. Tears were analysed using 2-D gel electrophoresis ( n = 25) and 1-D electrophoresis (n = 3). Lacryglobin was present in the fol lowing percentage of patients: breast cancer (88%), lung (83%), colon (100% ), ovary (33%), prostate (100%) and controls (60%). Two control patients wi th lacryglobin had a family history of breast and prostate cancer. Lacryglo bin was detected in some but not all tear samples and further studies are w arranted to investigate its potential as a marker for cancer.