title: Radiation-induced chromosomal instability in human mammary epithelial cells.
abstract: Karyotypes of human cells surviving X- and alpha-irradiation have been studied.  Human mammary epithelial cells of the immortal, non-tumorigenic cell line H184B5 F5-1 M/10 were irradiated and surviving clones isolated and expanded in culture.  Cytogenetic analysis was performed using dedicated software with an image analyzer.  We have found that both high- and low-LET radiation induced chromosomal instability in long-term cultures, but with different characteristics.  Complex chromosomal rearrangements were observed after X-rays, while chromosome loss predominated after alpha-particles.  Deletions were observed in both cases.  In clones derived from cells exposed to alpha-particles, some cells showed extensive chromosome breaking and double minutes.  Genomic instability was correlated to delayed reproductive death and neoplastic transformation.  These results indicate that chromosomal instability is a radiation-quality-dependent effect which could determine late genetic effects, and should therefore be carefully considered in the evaluation of risk for space missions.
authors.affiliation: Dipartimento di Scienze Fisiche, Università di Napoli "Federico II", Napoli, Italy.
authors.forename: M
authors.initials: M
authors.lastname: Durante
authors.forename: G F
authors.initials: GF
authors.lastname: Grossi
authors.forename: T C
authors.initials: TC
authors.lastname: Yang
mesh_terms: D000512:Alpha Particles; D000782:Aneuploidy; D001940:Breast / Q000166:cytology / Q000528:radiation effects*; D002460:Cell Line; D002470:Cell Survival / Q000528:radiation effects; D002471:Cell Transformation, Neoplastic / Q000235:genetics*; D002869:Chromosome Aberrations; D002882:Chromosomes, Human, Pair 13; D002889:Chromosomes, Human, Pair 2; D003359:Cosmic Radiation; D004307:Dose-Response Relationship, Radiation; D004847:Epithelial Cells; D004848:Epithelium / Q000528:radiation effects; D005260:Female; D006801:Humans; D018499:Linear Energy Transfer; D009381:Neoplasms, Radiation-Induced / Q000209:etiology / Q000235:genetics*; D010315:Particle Accelerators; D014965:X-Rays