Subtraction hybridization identifies a novel melanoma differentiation associated gene, mda-7, modulated during human melanoma differentiation, growth and progression

Oncogene. 1995 Dec 21;11(12):2477-86.


Cultured human melanoma cells lose proliferative capacity and terminally differentiate after treatment with the combination of recombinant human fibroblast interferon (IFN-beta) and mezerein (MEZ). Subtraction hybridization of cDNA libraries prepared from actively proliferating human H0-1 melanoma cells from cDNA libraries produced from H0-1 cells treated with IFN-beta + MEZ identifies a novel melanoma differentiation-associated (mda) cDNA, mda-7, that displays elevated expression in differentiation inducer-treated H0-1 cells. mda-7 encodes a novel protein of 206 amino acids with a predicted size of 23.8 kDa. The level of mda-7 mRNA is elevated in actively proliferating normal human melanocytes versus primary and metastatic human melanomas. In the Matrigel-assisted melanoma progression model, mda-7 expression decreases in early vertical growth phase primary human melanoma cells selected for autonomous or enhanced tumor formation in nude mice. Treatment of human melanomas with IFN-beta + MEZ, and to a lesser extent with MEZ, results in growth suppression and induced or enhanced mda-7 expression. Immunoprecipitation analyses using peptide-derived rabbit polyclonal antibodies detect increases in mda-7 protein, and a higher molecular weight protein of approximately 90 to 100 kDa, in MEZ and IFN-beta + MEZ treated H0-1 cells. mda-7 is a highly conserved gene with an homologous sequence in the genome of yeast. Transfection of mda-7 expression constructs into H0-1 and C8161 human melanoma cells reduces growth and inhibits colony formation. These results confirm that mda-7 has antiproliferative properties in human melanoma cells and in this context may contribute to terminal cell differentiation. The mda-7 gene may also function as a negative regulator of melanoma progression.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Base Sequence
  • Cell Differentiation
  • Cell Division
  • Cloning, Molecular
  • DNA, Complementary / chemistry
  • DNA, Complementary / isolation & purification*
  • Female
  • Gene Expression
  • Genes, Tumor Suppressor
  • Growth Substances / genetics*
  • Humans
  • Interleukins*
  • Melanoma / genetics*
  • Melanoma / pathology
  • Mice
  • Middle Aged
  • Molecular Sequence Data
  • Neoplasm Proteins / genetics*
  • Nucleic Acid Hybridization
  • Rabbits
  • Tumor Cells, Cultured


  • DNA, Complementary
  • Growth Substances
  • Interleukins
  • Neoplasm Proteins
  • interleukin-24

Associated data

  • GENBANK/U16261