The present invention relates to the identification of membrane proteins associated with B-cell non-Hodgkin's lymphoma, breast cancer, cervical cancer, colorectal cancer, gastric cancer, glioblastoma, hepatocellular carcinoma, lung cancer, lymphoid leukaemia (particularly acute T- cell leukaemia and chronic lymphocytic leukaemia), melanoma, neuroblastoma, osteosarcoma, ovarian cancer, pancreatic cancer, prostate cancer, renal cell cancer and retinoblastoma which have utility as markers and for treatment of said cancers and which also form biological targets against which antibodies such as therapeutic antibodies (or other affinity reagents) or other pharmaceutical agents can be made.
