CCND1 Amplification in Breast Cancer -associations With Proliferation, Histopathological Grade, Molecular Subtype and Prognosis

In this study ofCCND1 in primary BCs and corresponding axillary lymph node metastases (LNM),we examine associations betweenCCND1 CN in primary BCs and proliferation status, molecular subtype, and prognosis. Furthermore, we studied associations betweenCCND1 CN and CNs ofFGFR1 andZNF703, both of which are located on 8p12.  Fluorescence in situ hybridization probes forCCND1 and chromosome 11 centromere were used on tissue microarrays comprising 526 BCs and 123 LNM. We assessed associations betweenCCND1 CN and tumour characteristics using Pearson ’s χ2 test, and estimated cumulative risks of death from BC and hazard ratios in analysis of prognosis.  We foundCCND1 CN  ≥ 4 <  6 in 45 (8.6%) tumours, and ≥ 6 in 42 (8.0%).CCND1 CN ( ≥ 6) was seen in all molecular subtypes, most frequently in Luminal B (HER2−) (20/126; 16%). Increased  CCND1 CN was associated with high histopathological grade, high Ki-67, and high mitotic count, but not prognosis.CCND1 CN  ≥ 6 was accompanied by CN increase ofFGFR1 in 6/40 cases (15.0%) andZNF703 in 5/38 cases (13.2%). Three cases showed CN increase of all three genes.  HighCCND1 CN was most frequent in Luminal B (HER2−) tumours. Good correlation betweenCCND1 CNs in BCs and LNM was observed. Despite associations between high  CCND1 CN and aggressive tumour characteristics, the prognostic impact ofCCND1 CN remains unresolved.
Source: Journal of Mammary Gland Biology and Neoplasia - Category: Cancer & Oncology Source Type: research