Quantitative profiling of regional protein expression in rat retina after partial optic nerve transection using fluorescence difference two-dimensional gel electrophoresis
MOLECULAR MEDICINE REPORTS
Authors: Lam, Chuen; Li, King Kit; Do, Chi Wai; Chan, Henry; To, Chi Ho; Kwong, Jacky Man Kwong
Abstract
To examine the difference between primary and secondary retinal ganglion cell (RGC) degeneration, the protein expression at four regions of retina including superior, temporal, inferior and nasal quadrant in a rat model of partial optic nerve transection (pONT) using 2-D Fluorescence Difference Gel Electrophoresis (DIGE) were investigated. Unilateral pONT was performed on the temporal side of optic nerves of adult Wistar rats to separate primary and secondary RGC loss. Topographical quantification of RGCs labeled by Rbpms antibody and analysis of axonal injury by grading of optic nerve damage at 1 week (n=8) and 8 weeks (n=15) after pONT demonstrated early RGC loss at temporal region, which is considered as primary RGC degeneration and progressing RGC loss at nasal region, which is considered as secondary RGC degeneration. Early protein expression in each retinal quadrant (n=4) at 2 weeks after pONT was compared with the corresponding quadrant in the contralateral control eye by DIGE. For all comparisons, 24 differentially expressed proteins (>1.2-fold; P<0.05; >= 3 non-duplicated peptide matches) were identified by mass spectrometry (MS). Interestingly, in the nasal retina, serum albumin and members of crystallin family, including alpha A, alpha B, beta A2, beta A3, beta B2 and gamma S indicating stress response were upregulated. By contrast, only alpha B and beta A2 crystallin proteins were altered in temporal quadrant. In the superior and inferior quadrants, beta B2 crystallin, keratin type I, S-arrestin and lamin-B1 were upregulated, while heat shock cognate 71 kDa protein and heterogeneous nuclear ribonucleoproteins A2/B1 were downregulated. In summary, the use of DIGE followed by MS is useful to detect early regional protein regulation in the retina after localized optic nerve injury.
RUNX1 Mutations Are Associated With Poor Outcome in Younger and Older Patients With Cytogenetically Normal Acute Myeloid Leukemia and With Distinct Gene and MicroRNA Expression Signatures
JOURNAL OF CLINICAL ONCOLOGY
Authors: Mendler, Jason H.; Maharry, Kati; Radmacher, Michael D.; Mrozek, Krzysztof; Becker, Heiko; Metzeler, Klaus H.; Schwind, Sebastian; Whitman, Susan P.; Khalife, Jihane; Kohlschmidt, Jessica; Nicolet, Deedra; Powell, Bayard L.; Carter, Thomas H.; Wetzler, Meir; Moore, Joseph O.; Kolitz, Jonathan E.; Baer, Maria R.; Carroll, Andrew J.; Larson, Richard A.; Caligiuri, Michael A.; Marcucci, Guido; Bloomfield, Clara D.
Abstract
Purpose To determine the association of RUNX1 mutations with therapeutic outcome in younger and older patients with primary cytogenetically normal acute myeloid leukemia (CN-AML) and with gene/microRNA expression signatures. Patients and Methods Younger (< 60 years; n = 175) and older (>= 60 years; n = 225) patients with CN-AML treated with intensive cytarabine/anthracycline-based first-line therapy on Cancer and Leukemia Group B protocols were centrally analyzed for RUNX1 mutations by polymerase chain reaction and direct sequencing and for established prognostic gene mutations. Gene/microRNA expression profiles were derived using microarrays. Results RUNX1 mutations were found in 8% and 16% of younger and older patients, respectively (P = .02). They were associated with ASXL1 mutations (P < .001) and inversely associated with NPM1 (P < .001) and CEBPA (P = .06) mutations. RUNX1-mutated patients had lower complete remission rates (P = .005 in younger; P = .006 in older) and shorter disease-free survival (P = .058 in younger; P < .001 in older), overall survival (P = .003 in younger; P < .001 in older), and event-free survival (P < .001 for younger and older) than RUNX1 wild-type patients. Because RUNX1 mutations were more common in older patients and almost never coexisted with NPM1 mutations, RUNX1 mutation-associated expression signatures were derived in older, NPM1 wild-type patients and featured upregulation of genes normally expressed in primitive hematopoietic cells and B-cell progenitors, including DNTT, BAALC, BLNK, CD109, RBPMS, and FLT3, and downregulation of promoters of myelopoiesis, including CEBPA and miR-223. Conclusion RUNX1 mutations are twice as common in older than younger patients with CN-AML and negatively impact outcome in both age groups. RUNX1-mutated blasts have molecular features of primitive hematopoietic and lymphoid progenitors, potentially leading to novel therapeutic approaches. J Clin Oncol 30: 3109-3118. (C) 2012 by American Society of Clinical Oncology