👤 Martha L Slattery

Proteomics provides an opportunity for detection and monitoring of anorexia nervosa (AN) and its related variant, atypical-AN (atyp-AN). However, research to date has been limited by the small number of proteins explored, exclusive focus on adults with AN, and lack of replication across studies. This study performed Olink Proseek Multiplex profiling of 92 proteins involved in inflammation among females with AN and atyp-AN (N = 64), all < 90% of expected body weight, and age-matched healthy controls (HC; N=44). After correction for multiple testing, nine proteins differed significantly in the AN/atyp-AN group relative to HC group ( Show less

Known genetic loci explain only a small proportion of the familial relative risk of colorectal cancer (CRC). We conducted a genome-wide association study of CRC in East Asians with 14,963 cases and 31,945 controls and identified 6 new loci associated with CRC risk (P = 3.42 × 10(-8) to 9.22 × 10(-21)) at 10q22.3, 10q25.2, 11q12.2, 12p13.31, 17p13.3 and 19q13.2. Two of these loci map to genes (TCF7L2 and TGFB1) with established roles in colorectal tumorigenesis. Four other loci are located in or near genes involved in transcriptional regulation (ZMIZ1), genome maintenance (FEN1), fatty acid metabolism (FADS1 and FADS2), cancer cell motility and metastasis (CD9), and cell growth and differentiation (NXN). We also found suggestive evidence for three additional loci associated with CRC risk near genome-wide significance at 8q24.11, 10q21.1 and 10q24.2. Furthermore, we replicated 22 previously reported CRC-associated loci. Our study provides insights into the genetic basis of CRC and suggests the involvement of new biological pathways. Show less

Mitogen-activated protein kinase (MAPK) pathways regulate many cellular functions including cell proliferation, differentiation, migration and apoptosis. We evaluate genetic variation in the c-Jun-N-terminal kinases, p38, and extracellular regulated kinases 1/2 MAPK-signaling pathways and colon and rectal cancer risk using data from population-based case-control studies (colon: n = 1555 cases, 1956 controls; rectal: n = 754 cases, 959 controls). We assess 19 genes (DUSP1, DUSP2, DUSP4, DUSP6, DUSP7, MAP2K1, MAP3K1, MAP3K2, MAP3K3, MAP3K7, MAP3K9, MAP3K10, MAP3K11, MAPK1, MAPK3, MAPK8, MAPK12, MAPK14 and RAF1). MAP2K1 rs8039880 [odds ratio (OR) = 0.57, 95% confidence interval (CI) = 0.38, 0.83; GG versus AA genotype] and MAP3K9 rs11625206 (OR = 1.41, 95% CI = 1.14, 1.76; recessive model) were associated with colon cancer (P (adj) value < 0.05). DUSP1 rs322351 (OR = 1.43, 95% CI = 1.09, 1.88; TT versus CC) and MAPK8 rs10857561 (OR = 1.48, 95% CI 1.08, 2.03; AA versus GG/GA) were associated with rectal cancer (P (adj) < 0.05). Aspirin/non-steroidal anti-inflammatory drug, cigarette smoking and body mass index interacted with several genes to alter cancer risk. Genetic variants had unique associations with KRAS, TP53 and CIMP+ tumors. DUSP2 rs1724120 [hazard rate ratio (HRR) = 0.72, 95%CI = 0.54, 0.96; AA versus GG/GA), MAP3K10 rs112956 (HRR = 1.40, 95% CI = 1.10, 1.76; CT/TT versus CC) and MAP3K11 (HRR = 1.76, 95% CI 1.18, 2.62 TT versus GG/GT) influenced survival after diagnosis with colon cancer; MAP2K1 rs8039880 (HRR = 2.53, 95% CI 1.34, 4.79 GG versus AG/GG) and Raf1 rs11923427 (HRR = 0.59 95% CI = 0.40, 0.86; AA versus TT/TA) were associated with rectal cancer survival. These data suggest that genetic variation in the MAPK-signaling pathway influences colorectal cancer risk and survival after diagnosis. Associations may be modified by lifestyle factors that influence inflammation and oxidative stress. Show less

Azf1 activates CLN3 transcription in Saccharomyces cerevisiae cells growing in glucose. Paradoxically, other studies have shown Azf1 to be almost undetectable in glucose-grown cells. Microarray experiments showed that Azf1 activates nonoverlapping gene sets in different carbon sources: in glucose, Azf1 activates carbon and energy metabolism genes, and in glycerol-lactate, Azf1 activates genes needed for cell wall maintenance. Consistent with the decreased expression of cell wall maintenance genes observed with azf1Delta mutants, we observed a marked growth defect in the azf1Delta cells at 37 degrees C in nonfermentable medium. Cell wall integrity assays, such as sensitivity to calcofluor white, sodium dodecyl sulfate, or caffeine, confirmed cell wall defects in azf1Delta mutants in nonfermentable medium. Gel shift experiments show that Azf1 binds to DNA elements with the sequence AAAAGAAA (A4GA3), a motif enriched in the promoters of Azf1-sensitive genes and predicted by whole-genome studies. This suggests that many of the Azf1-dependent transcripts may be regulated directly by Azf1 binding. We found that the levels of Azf1 protein in glucose-grown cells were comparable to Azf1 levels in cells grown in glycerol-lactate; however, this could only be demonstrated with a cell extraction procedure that minimizes proteolysis. Glucose produces conditions that destabilize the Azf1 protein, a finding that may reflect a glucose-induced change in Azf1 tertiary or quaternary structure. Show less

Saccharomyces cerevisiae cells reproduce by budding to yield a mother cell and a smaller daughter cell. Although both mother and daughter begin G1 simultaneously, the mother cell progresses through G1 more rapidly. Daughter cell G1 delay has long been thought to be due to a requirement for attaining a certain critical cell size before passing the commitment point in the cell cycle known as START. We present an alternative model in which the daughter cell-specific Ace2 transcription factor delays G1 in daughter cells. Deletion of ACE2 produces daughter cells that proceed through G1 at the same rate as mother cells, whereas a mutant Ace2 protein that is not restricted to daughter cells delays G1 equally in both mothers and daughters. The differential in G1 length between mothers and daughters requires the Cln3 G1 cyclin, and CLN3-GFP reporter expression is reduced in daughters in an ACE2-dependent manner. Specific daughter delay elements in the CLN3 promoter are required for normal daughter G1 delay, and these elements bind to an unidentified 127-kDa protein. This DNA-binding activity is enhanced by deletion of ACE2. These results support a model in which daughter cell G1 delay is determined not by cell size but by an intrinsic property of the daughter cell generated by asymmetric cell division. Show less

Nutrient-limited Saccharomyces cerevisiae cells rapidly resume proliferative growth when transferred into glucose medium. This is preceded by a rapid increase in CLN3, BCK2, and CDC28 mRNAs encoding cell cycle regulatory proteins that promote progress through Start. We have tested the ability of mutations in known glucose signaling pathways to block glucose induction of CLN3, BCK2, and CDC28. We find that loss of the Snf3 and Rgt2 glucose sensors does not block glucose induction, nor does deletion of HXK2, encoding the hexokinase isoenzyme involved in glucose repression signaling. Rapamycin blockade of the Tor nutrient sensing pathway does not block the glucose response. Addition of 2-deoxy glucose to the medium will not substitute for glucose. These results indicate that glucose metabolism generates the signal required for induction of CLN3, BCK2, and CDC28. In support of this conclusion, we find that addition of iodoacetate, an inhibitor of the glyceraldehyde-3-phosphate dehydrogenase step in yeast glycolysis, strongly downregulates the levels CLN3, BCK2, and CDC28 mRNAs. Furthermore, mutations in PFK1 and PFK2, which encode phosphofructokinase isoforms, inhibit glucose induction of CLN3, BCK2, and CDC28. These results indicate a link between the rate of glycolysis and the expression of genes that are critical for passage through G(1). Show less