title: CD44 and HCELL: preventing hematogenous metastasis at step 1.
abstract: Despite great strides in our knowledge of the genetic and epigenetic changes underlying malignancy, we have limited information on the molecular basis of metastasis. Over 90% of cancer deaths are caused by spread of tumor cells from a primary site to distant organs and tissues, highlighting the pressing need to define the molecular effectors of cancer metastasis. Mounting evidence suggests that circulating tumor cells (CTCs) home to specific tissues by hijacking the normal leukocyte trafficking mechanisms. Cancer cells characteristically express CD44, and there is increasing evidence that hematopoietic cell E-/L-selectin ligand (HCELL), a sialofucosylated glycoform of CD44, serves as the major selectin ligand on cancer cells, allowing interaction of tumor cells with endothelium, leukocytes, and platelets. Here, we review the structural biology of CD44 and of HCELL, and present current data on the function of these molecules in mediating organ-specific homing/metastasis of CTCs.
authors.affiliation: Department of Dermatology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA.
authors.forename: Pieter P
authors.initials: PP
authors.lastname: Jacobs
authors.forename: Robert
authors.initials: R
authors.lastname: Sackstein
mesh_terms: D000818:Animals; D001792:Blood Platelets / Q000378:metabolism / Q000473:pathology; D002450:Cell Communication; D004727:Endothelium / Q000378:metabolism / Q000473:pathology; D044127:Epigenesis, Genetic; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D018960:Hyaluronan Receptors / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D007962:Leukocytes / Q000378:metabolism / Q000473:pathology; D009363:Neoplasm Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D009360:Neoplastic Cells, Circulating / Q000378:metabolism* / Q000473:pathology; D014411:Neoplastic Stem Cells / Q000378:metabolism* / Q000473:pathology; D017434:Protein Structure, Tertiary; D013329:Structure-Activity Relationship
chemical_list: D018960:Hyaluronan Receptors; D009363:Neoplasm Proteins; C497483:CD44 protein, human