Inter-tumor genomic heterogeneity of breast cancers: comprehensive genomic profile of primary early breast cancers and relapses
BREAST CANCER RESEARCH
Authors: Fumagalli, Caterina; Ranghiero, Alberto; Gandini, Sara; Corso, Federica; Taormina, Sergio; De Camilli, Elisa; Rappa, Alessandra; Vacirca, Davide; Viale, Giuseppe; Guerini-Rocco, Elena; Barberis, Massimo
Abstract
Background The breast cancer genome dynamically evolves during malignant progression and recurrence. We investigated the genomic profiles of primary early-stage breast cancers and matched relapses to elucidate the molecular underpinnings of the metastatic process, focusing on potentially actionable alterations in the recurrences. Methods A mono-institutional cohort of 128 patients with breast cancers (n = 68 luminal B HER2,n = 6 luminal B HER2+,n = 1 HER2+ non-luminal,n = 56 triple negative) and at least one recurrence in a timeframe of 17 years was evaluated. Next-generation sequencing comprehensive genomic profiling was performed on 289 formalin-fixed paraffin-embedded (FFPE) samples, including primary tumors and matched relapses. Correlations of genomic aberrations with clinicopathologic factors and time to breast cancer relapse were analyzed. Results Genomic data were available for 188 of 289 FFPE samples that achieved the sequencing quality parameters (failure rate 34.9%), including 106 primary tumors and 82 relapses. All primary and relapse samples harbored at least one genomic alteration, with a median number of six alterations per sample (range 1-16). The most frequent somatic genomic alterations were mutations ofTP53(primary tumors = 49%, relapses = 49%) andPIK3CA(primary tumors = 33%, relapses = 30%). Distinctive genomic alterations of primary tumors were significantly associated with molecular subtypes.TP53,PIK3R1, andNF1somatic alterations were more frequently detected in triple negative tumors (pvalue < 0.05);CCND1,FGF3, andFGFR1copy number gains were recurrently identified in luminal cases (pvalue < 0.05). Moreover,TP53mutations andMYCamplification were significantly and independently associated with a shorter time to relapse (pvalue < 0.05). Molecular subtype changes between primary tumors and relapses were seen in 10 of 128 (7.8%) cases. Most driver genomic alterations (55.8%) were shared between primary tumors and matched recurrences. However, in 39 of 61 cases (63.9%), additional private alterations were detected in the relapse samples only, including 12 patients with potentially actionable aberrations. Conclusions Specific genomic aberrations of primary breast cancers were associated with time to relapse. Primary tumors and matched recurrences showed a core of shared driver genomic aberrations but private actionable alterations have been identified in the relapses.
Catechol-O-Methyltransferase Gene Polymorphisms and the Risk of Chemotherapy-Induced Prospective Memory Impairment in Breast Cancer Patients with Varying Tumor Hormonal Receptor Expression
MEDICAL SCIENCE MONITOR
Authors: Li, Wen; Zhao, Jingjing; Ding, Ke; Chao, Herta H.; Li, Chiang-Shan R.; Cheng, Huaidong; Shen, Li
Abstract
Background: Existing research evidence indicates that breast cancer patients have different degrees of cognitive dysfunction after chemotherapy, and polymorphisms in 3 genes (catechol-O-methyltransferase, COMT; apolipoprotein E, APOE; and brain-derived neurotrophic factor, BDNF) have been associated with cognitive impairment. However, the role of these 3 gene polymorphisms in modulating cognitive impairment in breast cancer survivors with varying hormonal receptor expression is not clear at present. To explore the effects of genetic polymorphisms in BDNF, APOE, and COMT on the regulation of prospective memory impairments induced by chemotherapy in breast cancer patients with various expression levels of estrogen receptor (ER) and progesterone receptor (PR). Material/Methods: A total of 232 patients with breast cancer (113 with ER-/PR- and 119 with ER+/PR+) were evaluated before and after chemotherapy for cognitive function, including prospective memory. Following previously published sequencing procedures, we assessed 6 single-nucleotide polymorphisms (SNPs), including BDNF (rs6265), APOE (rs429358, rs7412), and COMT (rs165599, rs4680, rs737865). Results: The patients showed poorer prospective memory scores after chemotherapy than before chemotherapy. Furthermore, the ER-/PR- group showed poorer event-based prospective memory (EBPM) scores than the ER+/PR+ group (z=-7.831, p<0.01) after chemotherapy. The patients with the COMT rs737865G/G genotype, compared with those with the A/A and A/G genotypes, showed a linear EBPM performance (beta=1.499, 95% confidence interval (CI)=1.017 similar to 2.211) and were less likely to have memory impairment. In contrast, APOE and BDNF polymorphisms did not influence cognitive performance. Conclusions: The patterns of hormonal receptor expression may be related to prospective memory impairments induced by chemotherapy in breast cancer patients. Furthermore, the COMT polymorphism (rs737865) was linearly related to the extent of deficits in EBPM and may represent a potential genetic marker of risk for cognitive deficits triggered by chemotherapy in patients with breast cancer.