The opening of a critical-fluctuation-induced pseudogap ͑or precursor pseudogap͒ in the one-particle spectral weight of the half-filled two-dimensional Hubbard model is discussed. This pseudogap, appearing in our Monte Carlo simulations, may be obtained from many-body techniques that use Green functions and vertex corrections that are at the same level of approximation. Self-consistent theories of the Eliashberg type ͑such as the fluctuation exchange approximation͒ use renormalized Green functions and bare vertices in a context where there is no Migdal theorem. They do not find the pseudogap, in quantitative and qualitative disagreement with simulations, suggesting these methods are inadequate for this problem. Differences between precursor pseudogaps and strong-coupling pseudogaps are also discussed.

Clinical evidence suggests that estradiol replacement therapy reduces colon cancer risk in ‘post’menopausal women. In colon epithelial cells, the estrogen receptor β (ERβ) is the predominant ER subtype and is thought to mediate the genomic effect of estrogens. The first aim of this study was to investigate the consequence of ERβ deficiency on intestinal tumorigenesis in the ApcMin/+ mouse model. Furthermore, to explore the biological mechanisms by which estrogens may influence the pathogenesis of colorectal cancer, we performed gene expression profiles in colonocytes from ovariectomized wild‐type (WT) vs. ERβ−/− mice, treated with estradiol (E2) or vehicle. Specifically in female, ERβ deficiency was found to be associated with higher adenoma multiplicity in the small intestine, but not in the colon. Furthermore, tumors from ERβ−/−ApcMin/+ female mice were on average significantly larger than those from control ApcMin/+ mice. Higher steady‐state proliferation in epithelial cells of the jejunum and colon from ERβ−/−ApcMin/+ vs. ApcMin/+ female mice was confirmed by BrdU incorporation assay. Interestingly, functional categorization of microarray results revealed the TGFβ signaling pathway to be modulated in colonocytes, especially for the WT + E2 vs. WT + Vehicle and the ERβ−/− + E2 vs. WT + E2 comparisons. Using quantitative PCR analysis, we observed transcripts from ligands of the TGFβ pathway to be upregulated in colonocytes from E2‐treated WT and ERβ−/− mice and downregulated in ERβ‐deficient mice, mostly in an E2‐independent manner. Therefore, our results demonstrate that ERβ deficiency enhances small intestinal tumorigenesis and suggest that modulation of the TGFβ signaling pathway could contribute to the protective role of estrogens on intestinal tumorigenesis. © 2008 Wiley‐Liss, Inc.

ImportanceEarly results at 3 years from the PRODIGE 24/Canadian Cancer Trials Group PA6 randomized clinical trial showed survival benefits with adjuvant treatment with modified FOLFIRINOX vs gemcitabine in patients with resected pancreatic ductal adenocarcinoma; mature data are now available.ObjectiveTo report 5-year outcomes and explore prognostic factors for overall survival.Design, Setting, and ParticipantsThis open-label, phase 3 randomized clinical trial was conducted at 77 hospitals in France and Canada and included patients aged 18 to 79 years with histologically confirmed pancreatic ductal adenocarcinoma who had undergone complete macroscopic (R0/R1) resection within 3 to 12 weeks before randomization. Patients were included from April 16, 2012, through October 3, 2016. The cutoff date for this analysis was June 28, 2021.InterventionsA total of 493 patients were randomized (1:1) to receive treatment with modified FOLFIRINOX (oxaliplatin, 85 mg/m2 of body surface area; irinotecan, 150-180 mg/m2; leucovorin, 400 mg/m2; and fluorouracil, 2400 mg/m2, every 2 weeks) or gemcitabine (1000 mg/m2, days 1, 8, and 15, every 4 weeks) as adjuvant therapy for 24 weeks.Main Outcomes and MeasuresPrimary end point was disease-free survival. Secondary end points included overall survival, metastasis-free survival, and cancer-specific survival. Prognostic factors for overall survival were determined.ResultsOf the 493 patients, 216 (43.8%) were women, and the mean (SD) age was 62.0 (8.9) years. At a median of 69.7 months’ follow-up, 367 disease-free survival events were observed. In patients receiving chemotherapy with modified FOLFIRINOX vs gemcitabine, median disease-free survival was 21.4 months (95% CI, 17.5-26.7) vs 12.8 months (95% CI, 11.6-15.2) (hazard ratio [HR], 0.66; 95% CI, 0.54-0.82; P < .001) and 5-year disease-free survival was 26.1% vs 19.0%; median overall survival was 53.5 months (95% CI, 43.5-58.4) vs 35.5 months (95% CI, 30.1-40.3) (HR, 0.68; 95% CI, 0.54-0.85; P = .001), and 5-year overall survival was 43.2% vs 31.4%; median metastasis-free survival was 29.4 months (95% CI, 21.4-40.1) vs 17.7 months (95% CI, 14.0-21.2) (HR, 0.64; 95% CI, 0.52-0.80; P < .001); and median cancer-specific survival was 54.7 months (95% CI, 45.8-68.4) vs 36.3 months (95% CI, 30.5–43.9) (HR, 0.65; 95% CI, 0.51-0.82; P < .001). Multivariable analysis identified modified FOLFIRINOX, age, tumor grade, tumor staging, and larger-volume center as significant favorable prognostic factors for overall survival. Shorter relapse delay was an adverse prognostic factor.Conclusions and RelevanceThe final 5-year results from the PRODIGE 24/Canadian Cancer Trials Group PA6 randomized clinical trial indicate that adjuvant treatment with modified FOLFIRINOX yields significantly longer survival than gemcitabine in patients with resected pancreatic ductal adenocarcinoma.Trial RegistrationEudraCT: 2011-002026-52; ClinicalTrials.gov Identifier: NCT01526135

Purpose We investigated the translational value of reflex testing for germline mutations in four homology-directed DNA repair predisposition genes ( BRCA1, BRCA2, PALB2, and ATM) in consecutive patients with pancreatic adenocarcinoma. Methods One hundred fifty patients with French-Canadian (FC) ancestry were evaluated for founder mutations, and 114 patients were subsequently assessed by full gene sequencing and multiplex ligation-dependent probe amplification for nonfounder mutations. Two hundred thirty-six patients unselected for ancestry were also assessed for mutations by full gene sequencing. Results The FC founder mutation prevalence among the 150 patients was 5.3% (95% CI, 2.6% to 10.3%), and the nonfounder mutation prevalence across the four genes among the 114 patients tested was 2.6% (95% CI, 0.6% to 7.8%). In the case series unselected for ancestry, 10.0% (95% CI, 2.7% to 26.4%) of patients reporting Ashkenazi Jewish (AJ) ancestry carried an AJ founder mutation, with no nonfounder mutations identified. The mutation prevalence among patients without FC/AJ ancestry was 4.9% (95% CI, 2.6% to 8.8%). Mutations were more frequent in patients diagnosed at ≤ 50 years of age ( P = .03) and in patients with either two or more first- or second-degree relatives with pancreas, breast, ovarian or prostate cancer, or one such relative and a second primary of one of these cancer types ( P < .001). BRCA1, BRCA2, and PALB2 carriers with late-stage (III or IV) disease had an overall survival advantage ( P = .049), particularly if treated with platinum-based chemotherapies ( P = .030). Conclusion Considering these results, we recommend reflex founder mutation testing of patients with FC/AJ ancestry and full gene sequencing of patients who are ≤ 50 years or meet the identified family history criteria. Reflex testing of all incident patients for these four genes may become justified as full gene sequencing costs decline.