Many components of the CHIEF (Convergence of Hormones, Inflammation, and Energy Related Factors) pathway could influence survival given their involvement in cell growth, apoptosis, angiogenesis, and ...tumor invasion stimulation. We used ARTP (Adaptive Rank Truncation Product) to test if genes in the pathway were associated with colorectal cancer-specific mortality. Colon cancer (n = 1555) and rectal cancer (n = 754) cases were followed over five years. Age, center, stage at diagnosis, and tumor molecular phenotype were considered when calculating ARTP p values. A polygenic risk score was used to summarize the magnitude of risk associated with this pathway. The JAK/STAT/SOC was significant for colon cancer survival (PARTP = 0.035). Fifteen genes (DUSP2, INFGR1, IL6, IRF2, JAK2, MAP3K10, MMP1, NFkB1A, NOS2A, PIK3CA, SEPX1, SMAD3, TLR2, TYK2, and VDR) were associated with colon cancer mortality (PARTP < 0.05); JAK2 (PARTP = 0.0086), PIK3CA (PARTP = 0.0098), and SMAD3 (PARTP = 0.0059) had the strongest associations. Over 40 SNPs were significantly associated with survival within the 15 significant genes (PARTP < 0.05). SMAD3 had the strongest association with survival (HRGG 2.46 95% CI 1.44,4.21 PTtrnd = 0.0002). Seven genes (IL2RA, IL8RA, IL8RB, IRF2, RAF1, RUNX3, and SEPX1) were significantly associated with rectal cancer (PARTP < 0.05). The HR for colorectal cancer-specific mortality among colon cancer cases in the upper at-risk alleles group was 11.81 (95% CI 7.07, 19. 74) and was 10.99 (95% CI 5.30, 22.78) for rectal cancer. These results suggest that several genes in the CHIEF pathway are important for colorectal cancer survival; the risk associated with the pathway merits validation in other studies.
microRNAs (miRNA) repress messenger RNAs post-transcriptionally through binding to the 3' UTR of the mRNA with the miRNA seed region. It has been purported that longer seed regions have a greater ...efficacy on mRNA repression. We tested this hypothesis by evaluating differential expression of miRNAs involved in regulating the immune response, an important mechanism in colorectal cancer (CRC), by seed length category. We subsequently evaluated differential expression of these miRNAs' targets in colonic tissue and the impact of these miRNAs on CRC survival. We determined sequence complementarity between each miRNA seed region and the 3' UTR of each experimentally verified mRNA target gene. We classified miRNAs into groups based on seed regions matching perfectly to a mRNA UTR with six bases beginning at position two, seven bases beginning at position one, seven bases beginning at position two, or eight bases beginning at position one. We analyzed these groups in terms of miRNA differential expression between carcinoma and normal colorectal mucosa, differential colonic target mRNA expression, and risk of dying from CRC. After correction for multiple comparisons, the proportion of the miRNAs that were associated with differential mRNA expression was 0% for the 6-mer, 13.64% for the 7α-mer group, 12.82% for the 7β-mer group, and 8.70% for the 8-mer group. The proportion of miRNAs associated with survival was 20% for the 6-mer group, 27.27% for the 7α-mer group, 10.23% for the 7β-mer group, and 21.74% for the 8-mer group. We did not see a linear relationship between seed length and miRNA expression dysregulation, mRNA expression, or survival. Our findings do not support the hypothesis the seed region length alone influences mRNA repression.
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.
When genomics researchers design a high-throughput study to test for differential expression, some biological systems and research questions provide opportunities to use paired samples from subjects, ...and researchers can plan for a certain proportion of subjects to have paired samples. We consider the effect of this paired samples proportion on the statistical power of the study, using characteristics of both count (RNA-Seq) and continuous (microarray) expression data from a colorectal cancer study.
We demonstrate that a higher proportion of subjects with paired samples yields higher statistical power, for various total numbers of samples, and for various strengths of subject-level confounding factors. In the design scenarios considered, the statistical power in a fully-paired design is substantially (and in many cases several times) greater than in an unpaired design.
For the many biological systems and research questions where paired samples are feasible and relevant, substantial statistical power gains can be achieved at the study design stage when genomics researchers plan on using paired samples from the largest possible proportion of subjects. Any cost savings in a study design with unpaired samples are likely accompanied by underpowered and possibly biased results.
Low dietary folate intake is associated with several neoplasias, but reports are inconsistent for breast cancer. Additionally, the association of folate with breast cancer estrogen receptor (ER) ...status is not well established.
To determine if dietary intakes of folate, B-vitamins (B2, B6, B12) and methionine are associated with breast cancer risk and ER status in Hispanic, and non-Hispanic White women in the southwestern U.S.
Primary breast cancer cases (n = 2,325) in the 4-Corners region (Arizona, Colorado, New Mexico and Utah), diagnosed between October 1999 and May 2004, were identified through state cancer registries. Controls (n = 2,525) were frequency-matched by ethnicity and age (±5 years). Dietary intake, physical activity and other exposures were assessed using in-person interviews. Risk was assessed through multivariable and multinomial logistic regression with adjustment for relevant covariates.
While there was no overall association with breast cancer, the highest quartile of folate intake was marginally inversely associated with ER- breast cancer (Odds Ratio (OR) = 0.50, 95% CI 0.25-1.00, p for trend = 0.07). Vitamin B12 intake was inversely associated with breast cancer also (OR = 0.73, 95% CI 0.53-1.00, p for trend = 0.06), particularly for the highest quartile of ER+ breast cancer (OR = 0.67, 95% CI 0.46-0.99, p for trend = 0.06), among NHW women (OR = 0.49, 95% CI 0.29-0.81, p for trend = 0.01) and invasive breast cancer (OR = 0.63; 95% CI: 0.42, 0.93, P(trend) = 0.01). Methionine intake was also inversely associated with ER+ breast cancer (OR for 4th quartile = 0.83, 95% CI 0.66-1.03, p for trend = 0.04), primarily among Hispanic women (OR = 0.71, 95% CI 0.47-1.06, and P for trend = 0.02).
Higher intake of folate is marginally associated with a lower risk for ER- breast cancer, and higher intakes of vitamin B-12 and methionine are marginally associated with a lower risk of ER+ breast cancer.
The heterogeneity among colorectal tumors is probably due to differences in developmental pathways and might associate with patient survival times. We studied the relationship among markers of ...different subtypes of colorectal tumors and patient survival.
We pooled data from 7 observational studies, comprising 5010 patients with colorectal cancer. All the studies collected information on microsatellite instability (MSI), CpG island methylator phenotype (CIMP), and mutations in KRAS and BRAF in tumors. Tumors with complete marker data were classified as type 1 (MSI-high, CIMP-positive, with pathogenic mutations in BRAF but not KRAS), type 2 (not MSI-high, CIMP-positive, with pathogenic mutations in BRAF but not KRAS), type 3 (not MSI-high or CIMP, with pathogenic mutations in KRAS but not BRAF), type 4 (not MSI-high or CIMP, no pathogenic mutations in BRAF or KRAS), or type 5 (MSI-high, no CIMP, no pathogenic mutations in BRAF or KRAS). We used Cox regression to estimate hazard ratios (HR) and 95% confidence intervals (CIs) for associations of these subtypes and tumor markers with disease-specific survival (DSS) and overall survival times, adjusting for age, sex, stage at diagnosis, and study population.
Patients with type 2 colorectal tumors had significantly shorter time of DSS than patients with type 4 tumors (HRDSS 1.66; 95% CI 1.33–2.07), regardless of sex, age, or stage at diagnosis. Patients without MSI-high tumors had significantly shorter time of DSS compared with patients with MSI-high tumors (HRDSS 0.42; 95% CI 0.27–0.64), regardless of other tumor markers or stage, or patient sex or age.
In a pooled analysis of data from 7 observational studies of patients with colorectal cancer, we found that tumor subtypes, defined by combinations of 4 common tumor markers, were associated with differences in survival time. Colorectal tumor subtypes might therefore be used in determining patients’ prognoses.
Matrix metalloproteinases (MMPs) contribute to cancer through their involvement in cancer invasion and metastasis. We evaluated genetic variation in MMP1 (9 SNPs), MMP2 (8 SNPs), MMP3 (4 SNPs), and ...MMP9 (3 SNPs) and breast cancer risk among Hispanic (2111 cases, 2597 controls) and non-Hispanic white (NHW) (1481 cases, 1586 controls) women in the Breast Cancer Health Disparities Study. Ancestral informative markers (n = 104) were assessed to determine Native American (NA) ancestry. MMP1 4 single nucleotide polymorphisms (SNPs) and MMP2 (2 SNPs) were associated with breast cancer overall. MMP1 rs996999 had strongest associations among women with the most NA ancestry (OR 1.61,95% CI 1.09,2.40) as did MMP3 rs650108 (OR 1.36, 95% CI 1.05,1.75) and MMP9 rs3787268 (OR 1.52, 95% CI 1.09,2.13). The adaptive rank truncated product (ARTP) showed a significant pathway p(artp) value of 0.04, with a stronger association among women with the most NA ancestry (p(artp) = 0.02). Significant pathway genes using the ARTP were MMP1 for all women (p(artp) = 0.02) and MMP9 for women with the most NA ancestry (p(artp) = 0.024); MMP2 was borderline significant overall (p(artp) =0.06) and MMP1 and MMP3 were borderline significant for women with the most NA ancestry (p(artp) = 0.07 and 0.06 respectively). MMP1 and MMP2 were associated with ER+/PR+ and ER+/PR-tumors; MMP3 and MMP9 were associated with ER-/PR- tumors. The pathway was highly significant with survival (p(artp) = 0.0041) with MMP2 having the strongest gene association (p(artp) = 0.0007). Our findings suggest that genetic variation in MMP genes influence breast cancer development and survival in this genetically admixed population.
Fast-food consumption has increased greatly in the USA during the past three decades. However, the effect of fast food on risk of obesity and type 2 diabetes has received little attention. We aimed ...to investigate the association between reported fast-food habits and changes in bodyweight and insulin resistance over a 15-year period in the USA.
Participants for the CARDIA study included 3031 young (age 18–30 years in 1985–86) black and white adults who were followed up with repeated dietary assessment. We used multiple linear regression models to investigate the association of frequency of fast-food restaurant visits (fast-food frequency) at baseline and follow-up with 15-year changes in bodyweight and the homoeostasis model (HOMA) for insulin resistance.
Fast-food frequency was lowest for white women (about 1·3 times per week) compared with the other ethnic-sex groups (about twice a week). After adjustment for lifestyle factors, baseline fast-food frequency was directly associated with changes in bodyweight in both black (p=0·0050) and white people (p=0·0013). Change in fast-food frequency over 15 years was directly associated with changes in bodyweight in white individuals (p<0·0001), with a weaker association recorded in black people (p=0·1004). Changes were also directly associated with insulin resistance in both ethnic groups (p=0·0015 in black people, p<0·0001 in white people). By comparison with the average 15-year weight gain in participants with infrequent (less than once a week) fast-food restaurant use at baseline and follow-up (n=203), those with frequent (more than twice a week) visits to fast-food restaurants at baseline and follow-up (n=87) gained an extra 4·5 kg of bodyweight (p=0·0054) and had a two-fold greater increase in insulin resistance (p=0·0083).
Fast-food consumption has strong positive associations with weight gain and insulin resistance, suggesting that fast food increases the risk of obesity and type 2 diabetes.