The impact of re‐transurethral resection on clinical outcomes in a large multicentre cohort of patients with T1 high‐grade/Grade 3 bladder cancer treated with bacille Calmette–Guérin
Objectives To determine if a re‐transurethral resection (TUR), in the presence or absence of muscle at the first TUR in patients with T1‐high grade (HG)/Grade 3 (G3) bladder cancer, makes a difference in recurrence, progression, cancer specific (CSS) and overall survival (OS). Patients and methods In a large retrospective multicentre cohort of 2451 patients with T1‐HG/G3 initially treated with bacille Calmette–Guérin, 935 (38%) had a re‐TUR. According to the presence or absence of muscle in the specimen of the primary TUR, patients were divided in four groups: group 1 (no muscle, no re‐TUR), group 2 (no muscle, re‐TUR), group 3 (muscle, no re‐TUR) and group 4 (muscle, re‐TUR). Clinical outcomes were compared across the four groups. Results Re‐TUR had a positive impact on recurrence, progression, CSS and OS only if muscle was not present in the primary TUR specimen. Adjusting for the most important prognostic factors, re‐TUR in the absence of muscle had a borderline significant effect on time to recurrence [hazard ratio (HR) 0.67, P = 0.08], progression (HR 0.46, P = 0.06), CSS (HR 0.31, P = 0.07) and OS (HR 0.48, P = 0.05). Re‐TUR in the presence of muscle in the primary TUR specimen did not improve the outcome for any of the endpoints. Conclusions Our retrospective analysis suggests that re‐TUR may not be necessary in patients with T1‐HG/G3, if muscle is present in the specimen of the primary TUR.
Abstract B112: Transcriptome analysis in pancreatic cancer reveals a tumor suppressor function for HNF1A
Abstract Pancreatic ductal adenocarcinoma (PDAC), as with all cancer, is driven by dysregulation of genetic programs due to accumulation of somatic mutations, epigenetic modifications and changes in the micro-environment. Holistic views of perturbations in gene expression networks could illuminate key regulators and pathways for this highly lethal cancer. Toward this end, we performed massively-parallel mRNA-sequencing in normal (n = 10) and tumor (n = 8) derived pancreatic tissue samples as well as pancreatic cancer cell lines (n = 9), and determined differential gene expression (DE) patterns. Sub-network enrichment analyses of all expressed genes based on magnitude of DE identified HNF1A as the regulator of the most significantly and consistently dysregulated expression sub-network in our pancreatic tumor samples (median P = 7.56 x 10-7, median rank = 1, range = 1-25). To explore the effect of HNF1A expression in pancreatic tumor-derived cells we generated stable HNF1A-inducible clones in two pancreatic cancer cell lines. Induction of HNF1A overexpression caused severe growth inhibition (5.3-fold, P = 4.5x10-5 for MIA PaCa-2 clones; 7.2-fold, P = 2.2x10-5 for PANC-1 clones), and G0/G1 cell cycle arrest. This was accompanied by down-regulation of 49 out of 84 assayed cell cycle genes, while only 1 displayed increased expression. These data, combined with HNF1A’s direct regulation of pancreatic development and homeostasis genes (i.e. PDX1, PTF1A and NR5A2), suggest it may be an important tumor suppressor in pancreatic cells. Citation Format: Jason W. Hoskins, Marta Flandez, Jinping Jia, Hemang Parikh, Irene Collins, Mickey Emmanuel, Abdisamad Ibrahim, Wenming Xiao, John Powell, Nuria Malats, Gloria M. Petersen, Fransisco X. Real, Laufey T. Amundadottir. Transcriptome analysis in pancreatic cancer reveals a tumor suppressor function for HNF1A. [abstract]. In: Proceedings of the AACR Special Conference on Pancreatic Cancer: Innovations in Research and Treatment; May 18-21, 2014; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2015;75(13 Suppl):Abstract nr B112.
Identification of New Genetic Susceptibility Loci for Breast Cancer Through Consideration of Gene‐Environment Interactions
ABSTRACTGenes that alter disease risk only in combination with certain environmental exposures may not be detected in genetic association analysis. By using methods accounting for gene‐environment (G × E) interaction, we aimed to identify novel genetic loci associated with breast cancer risk. Up to 34,475 cases and 34,786 controls of European ancestry from up to 23 studies in the Breast Cancer Association Consortium were included. Overall, 71,527 single nucleotide polymorphisms (SNPs), enriched for association with breast cancer, were tested for interaction with 10 environmental risk factors using three recently proposed hybrid methods and a joint test of association and interaction. Analyses were adjusted for age, study, population stratification, and confounding factors as applicable. Three SNPs in two independent loci showed statistically significant association: SNPs rs10483028 and rs2242714 in perfect linkage disequilibrium on chromosome 21 and rs12197388 in ARID1B on chromosome 6. While rs12197388 was identified using the joint test with parity and with age at menarche (P‐values = 3 × 10−07), the variants on chromosome 21 q22.12, which showed interaction with adult body mass index (BMI) in 8,891 postmenopausal women, were identified by all methods applied. SNP rs10483028 was associated with breast cancer in women with a BMI below 25 kg/m2 (OR = 1.26, 95% CI 1.15–1.38) but not in women with a BMI of 30 kg/m2 or higher (OR = 0.89, 95% CI 0.72–1.11, P for interaction = 3.2 × 10−05). Our findings confirm comparable power of the recent methods for detecting G × E interaction and the utility of using G × E interaction analyses to identify new susceptibility loci.
A large-scale assessment of two-way SNP interactions in breast cancer susceptibility using 46 450 cases and 42 461 controls from the breast cancer association consortium
Abstract Part of the substantial unexplained familial aggregation of breast cancer may be due to interactions between common variants, but few studies have had adequate statistical power to detect interactions of realistic magnitude. We aimed to assess all two-way interactions in breast cancer susceptibility between 70 917 single nucleotide polymorphisms (SNPs) selected primarily based on prior evidence of a marginal effect. Thirty-eight international studies contributed data for 46 450 breast cancer cases and 42 461 controls of European origin as part of a multi-consortium project (COGS). First, SNPs were preselected based on evidence (P < 0.01) of a per-allele main effect, and all two-way combinations of those were evaluated by a per-allele (1 d.f.) test for interaction using logistic regression. Second, all 2.5 billion possible two-SNP combinations were evaluated using Boolean operation-based screening and testing, and SNP pairs with the strongest evidence of interaction (P < 10−4) were selected for more careful assessment by logistic regression. Under the first approach, 3277 SNPs were preselected, but an evaluation of all possible two-SNP combinations (1 d.f.) identified no interactions at P < 10−8. Results from the second analytic approach were consistent with those from the first (P > 10−10). In summary, we observed little evidence of two-way SNP interactions in breast cancer susceptibility, despite the large number of SNPs with potential marginal effects considered and the very large sample size. This finding may have important implications for risk prediction, simplifying the modelling required. Further comprehensive, large-scale genome-wide interaction studies may identify novel interacting loci if the inherent logistic and computational challenges can be overcome.
Confirmation of 5p12 As a Susceptibility Locus for Progesterone-Receptor–Positive, Lower Grade Breast Cancer