Spectral karyotyping demonstrates genetically unstable skin-homing T lymphocytes in cutaneous T-cell lymphoma.
We initially established cell lines from skin biopsies from four patients (MF8, MF18, MF19 and MF31) in early stages of cutaneous T-cell lymphoma (CTCL) in 1999. After 3 weeks of culture, skin-homing T lymphocytes were stimulated with phytohaemagglutinin. Metaphase spreads were analysed using spectral karyotyping (SKY), a molecular cytogenetic technique. MF18 and MF19 had predominantly normal karyotypes. MF8 had recurrent numerical aberrations resulting in two T lymphocyte clones: one with trisomy 21 (12/20 cells) and the other with monosomy chromosome 22 (3/20 cells). MF8 also exhibited a clonal deletion, del(5)(p15.1), as well as multiple non-clonal structural aberrations. MF31 had a clonal deletion, del(17)(p12) and other non-clonal deletions involving chromosomes 2, 5, 10, 11. MF18 had a single abnormal cell that contained two reciprocal translocations t(1;2)(q32;p21) and t(4;10)(p15.2;q24). In 2001, three of the original patients had new skin biopsies taken and cell lines were established. SKY analysis revealed the continued presence of a T-cell clone in MF8 with trisomy 21 (4/20 cells). Additionally, a new clone was seen with a del(18)(p11.2) (17/20 cells). MF31 had only one aberrant cell with a del(17)(p12). MF18 had a clonal deletion, [del(1)(p36.1) in 3/20 cells] and non-clonal aberrations involving chromosomes 3, 4, 5, 6, 12, 13, 17 and 18. Thus, three of four patients continued to show numerous numerical and structural aberrations, both clonal and non-clonal, with only MF8 having a recurring T lymphocyte clone (+21). Our findings demonstrate high genetic instability among skin-homing T lymphocytes even in early stages of CTCL. We did not see genetic instability or evidence of clones in cell lines from a patient with atopic dermatitis and one with psoriasis.
Padilla-Nash
Hesed M
HM
Genetics Branch, Center for Cancer Research, National Cancer Institute, NIH, Bethesda, MD 20892, USA. nashh@mail.nih.gov
Wu
Kaida
K
Just
Helle
H
Ried
Thomas
T
Thestrup-Pedersen
Kristian
K
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002471:Cell Transformation, Neoplastic / Q000473:pathology*; D002478:Cells, Cultured; D002869:Chromosome Aberrations; D005260:Female; D006801:Humans; D016410:Lymphoma, T-Cell, Cutaneous / Q000473:pathology*; D008297:Male; D012878:Skin Neoplasms / Q000473:pathology*; D032681:Spectral Karyotyping; D013601:T-Lymphocytes / Q000473:pathology*