title: Expression of the ALK protein by anaplastic large-cell lymphomas correlates with high proliferative activity.
abstract: A variable fraction of anaplastic large-cell lymphomas (ALCLs) exhibits a t(2;5)(p23;q35) translocation that results in expression of the chimeric hyperphosphorylated protein NPM-ALK (p80). Tumor cells expressing NPM-ALK exhibit markedly enhanced proliferative activity, but comparative cellular kinetic studies on ALK(+) (ALK lymphomas) and ALK(-) lymphomas are lacking. The present study showed that ALK(+) lymphomas, detected with the monoclonal antibody ALKc (n = 17), had significantly higher average values for the proliferation-associated parameters mitotic index, ana/telophase index, growth index (x x mitotic index - apoptotic index, assuming x = 3), percentages of Ki-67(+) cells and fraction of cells expressing cyclin A or B or the cell cycle-regulatory protein p34(cdc2) than did ALK(-) ALCLs (n = 15). Whether this intense proliferative activity contributes to the good response to chemotherapy and favorable outcome of ALK(+) ALCLs remains to be assessed in a larger series of patients. Our findings support the notion that ALK(+) and ALK(-) ALCLs are 2 distinct disease entities.
authors.affiliation: Institute of Pathology, University of Sassari, Sassari, Italy.
authors.forename: L
authors.initials: L
authors.lastname: Leoncini
authors.forename: S
authors.initials: S
authors.lastname: Lazzi
authors.forename: D
authors.initials: D
authors.lastname: Scano
authors.forename: A
authors.initials: A
authors.lastname: Mura
authors.forename: A
authors.initials: A
authors.lastname: Onida
authors.forename: G
authors.initials: G
authors.lastname: Massarelli
authors.forename: P
authors.initials: P
authors.lastname: Tosi
authors.forename: P
authors.initials: P
authors.lastname: Barbini
authors.forename: G
authors.initials: G
authors.lastname: Cevenini
authors.forename: M R
authors.initials: MR
authors.lastname: Massai
authors.forename: S
authors.initials: S
authors.lastname: Pileri
authors.forename: B
authors.initials: B
authors.lastname: Falini
authors.forename: A
authors.initials: A
authors.lastname: Giordano
authors.forename: R
authors.initials: R
authors.lastname: Kraft
authors.forename: J A
authors.initials: JA
authors.lastname: Laissue
authors.forename: H
authors.initials: H
authors.lastname: Cottier
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000077548:Anaplastic Lymphoma Kinase; D002455:Cell Division; D002648:Child; D019925:Cyclin A / Q000032:analysis; D019926:Cyclin B / Q000032:analysis; D005260:Female; D006801:Humans; D016403:Lymphoma, Large B-Cell, Diffuse / Q000378:metabolism / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D008940:Mitotic Index; D011505:Protein-Tyrosine Kinases / Q000032:analysis*; D020794:Receptor Protein-Tyrosine Kinases
chemical_list: D019925:Cyclin A; D019926:Cyclin B; C000626173:ALK protein, human; D000077548:Anaplastic Lymphoma Kinase; D011505:Protein-Tyrosine Kinases; D020794:Receptor Protein-Tyrosine Kinases