Molecular Diseases 2

More than one hundred years after its discovery, Edelman and Poulik identificated the Bence-Jones protein as the monoclonal light chain of immunoglobulin secreted by tumor plasma cells. Monoclonal paraproteins appear as sharp bands in the globulin area in electrophoretic patterns of serum. Diagnosis of multiple myeloma is often made based on this finding or on the presence of an elevated level of monoclonal immunoglobulin in the serum. Molecules in tumors arepresent in or produced by a tumor itself or by the host in response to a tumor that can be used to differentiate a tumor from normal tissue or to determine the presence of a tumor based on measurement in the blood or secretions. Such compounds can be found in cells, tissue or body fluids. It can be measured qualitatively or quantitatively by chemical, Immunological, or molecular biological methods to identify the presence of a tumors. Tumor markers can be broadly classified into tumor specific antigens and tumor-associated markers. Most tumor markers were often heralded as highly tumor specific, but subsequent studies demonstrated their presence in normal tissues of the adult or in various stages of ontogeny. Tumor markers may be classified into chemical and genetic tumor markers.. As a result, very few tumor-specific antigens can be recognized. The idiotypes of immunoglobulins of B cell tumors and certain neo-antigens of virus induced tumors are two examples that are strictly tumor specific. The vast majority of tumor markers are in reality tumor-associated antigens and can be classified into two types based on their size. The low-molecular weight tumor markers (-