Browsing by Author "Kim, Jisun"

Now showing 1 - 2 of 2
  • Thumbnail Image
    Item
    Differential effects of risk factors on the cognitive trajectory of early- and late-onset Alzheimer’s disease
    (BMC, 2021-06-14) Kim, Jaeho; Woo, Sook-Young; Kim, Seonwoo; Jang, Hyemin; Kim, Junpyo; Kim, Jisun; Kang, Sung Hoon; Na, Duk L.; Chin, Juhee; Apostolova, Liana G.; Seo, Sang Won; Kim, Hee Jin; Neurology, School of Medicine
    Background: Although few studies have shown that risk factors for Alzheimer's disease (AD) are associated with cognitive decline in AD, not much is known whether the impact of risk factors differs between early-onset AD (EOAD, symptom onset < 65 years of age) versus late-onset AD (LOAD). Therefore, we evaluated whether the impact of Alzheimer's disease (AD) risk factors on cognitive trajectories differ in EOAD and LOAD. Methods: We followed-up 193 EOAD and 476 LOAD patients without known autosomal dominant AD mutation for 32.3 ± 23.2 months. Mixed-effects model analyses were performed to evaluate the effects of APOE ε4, low education, hypertension, diabetes, dyslipidemia, and obesity on cognitive trajectories. Results: APOE ε4 carriers showed slower cognitive decline in general cognitive function, language, and memory domains than APOE ε4 carriers in EOAD but not in LOAD. Although patients with low education showed slower cognitive decline than patients with high education in both EOAD and LOAD, the effect was stronger in EOAD, specifically in frontal-executive function. Patients with hypertension showed faster cognitive decline than did patients without hypertension in frontal-executive and general cognitive function in LOAD but not in EOAD. Patients with obesity showed slower decline in general cognitive function than non-obese patients in EOAD but not in LOAD. Conclusions: Known risk factors for AD were associated with slower cognitive decline in EOAD but rapid cognitive decline in LOAD.
  • Thumbnail Image
    Item
    MYBL1 rearrangements and MYB amplification in breast adenoid cystic carcinomas lacking the MYB–NFIB fusion gene
    (Wiley, 2017) Kim, Jisun; Geyer, Felipe C.; Martelotto, Luciano G.; Ng, Charlotte K. Y.; Lim, Raymond S.; Selenica, Pier; Li, Anqi; Pareja, Fresia; Fusco, Nicola; Edelweiss, Marcia; Kumar, Rahul; Gularte-Merida, Rodrigo; Forbes, Andre N.; Khurana, Ekta; Mariani, Odette; Badve, Sunil; Vincent-Salomon, Anne; Norton, Larry; Reis-Filho, Jorge S.; Weigelt, Britta; Pathology and Laboratory Medicine, School of Medicine
    Breast adenoid cystic carcinoma (AdCC), a rare type of triple-negative breast cancer, has been shown to be driven by MYB pathway activation, most often underpinned by the MYB–NFIB fusion gene. Alternative genetic mechanisms, such as MYBL1 rearrangements, have been reported in MYB–NFIB-negative salivary gland AdCCs. Here we report on the molecular characterization by massively parallel sequencing of four breast AdCCs lacking the MYB–NFIB fusion gene. In two cases, we identified MYBL1 rearrangements (MYBL1–ACTN1 and MYBL1–NFIB), which were associated with MYBL1 overexpression. A third AdCC harboured a high-level MYB amplification, which resulted in MYB overexpression at the mRNA and protein levels. RNA-sequencing and whole-genome sequencing revealed no definite alternative driver in the fourth AdCC studied, despite high levels of MYB expression and the activation of pathways similar to those activated in MYB–NFIB-positive AdCCs. In this case, a deletion encompassing the last intron and part of exon 15 of MYB, including the binding site of ERG-1, a transcription factor that may downregulate MYB, and the exon 15 splice site, was detected. In conclusion, we demonstrate that MYBL1 rearrangements and MYB amplification probably constitute alternative genetic drivers of breast AdCCs, functioning through MYBL1 or MYB overexpression. These observations emphasize that breast AdCCs probably constitute a convergent phenotype, whereby activation of MYB and MYBL1 and their downstream targets can be driven by the MYB–NFIB fusion gene, MYBL1 rearrangements, MYB amplification, or other yet to be identified mechanisms. Copyright © 2017 Pathological Society of Great Britain and Ireland.