The present invention relates to the field of medicine and biology. It concerns a novel test for screening and for therapeutic follow-up in oncology. More particularly, it relates to diagnostic and/or therapeutic tests in oncology and on neurodegenerative diseases. It is a diagnostic test and a prognostic test for various cancers (breast cancer, bladder cancer, ovarian cancer, lung cancer, skin cancer, prostate cancer, colon cancer, liver cancer, glioblastoma, sarcoma, leukemia, etc.) and therapeutics solutions for specific neurodegenerative diseases. More particularly, the invention concerns the use of the LIV21 protein, LIV21 gene and of derivatives thereof as diagnostic and prognostic markers for cancers. The invention therefore concerns the detection of the LIV21 protein with a kit comprising LIV21-specific antibodies.
