Embryonic stem (ES) cells are capable of continuous self-renewal and pluripotential differentiation. A "core" set of transcription factors, Oct4, Sox2, and Nanog, maintains the ES cell state, whereas ...various combinations of factors, invariably including Oct4 and Sox2, reprogram somatic cells to pluripotency. We have sought to define the transcriptional network controlling pluripotency in mouse ES cells through combined proteomic and genomic approaches. We constructed a protein interaction network surrounding Nanog and determined gene targets of the core and reprogramming factors, plus others. The expanded transcriptional network we have constructed forms the basis for further studies of directed differentiation and lineage reprogramming, and a paradigm for comprehensive elucidation of regulatory pathways in other stem cells.
Escherichia coli purine nucleoside phosphorylase (PNP) expressed in tumors converts relatively nontoxic prodrugs into membrane-permeant cytotoxic compounds with high bystander activity. In the ...present study, we examined tumor regressions resulting from treatment with E. coli PNP and fludarabine phosphate (F-araAMP), a clinically approved compound used in the treatment of hematologic malignancies. We tested bystander killing with an adenoviral construct expressing E. coli PNP and then more formally examined thresholds for the bystander effect, using both MuLv and lentiviral vectoring. Because of the importance of understanding the mechanism of bystander action and the limits to this anticancer strategy, we also evaluated in vivo variables related to the expression of E. coli PNP (level of E. coli PNP activity in tumors, ectopic expression in liver, percentage of tumor cells transduced in situ, and accumulation of active metabolites in tumors). Our results indicate that F-araAMP confers excellent in vivo dose-dependent inhibition of bystander tumor cells, including strong responses in subcutaneous human glioma xenografts when 95 to 97.5% of the tumor mass is composed of bystander cells. These findings define levels of E. coli PNP expression necessary for antitumor activity with F-araAMP and demonstrate new potential for a clinically approved compound in solid tumor therapy.
Abstract
Background: The rapidly evolving landscape of systemic treatment for metastatic breast cancer (MBC) during the 1990s led to meaningful improvements in the overall survival (OS) of MBC ...patients1. Despite ongoing and expanded access to new treatments, it remains unclear if this has translated into further advances in survival. Moreover, the prognosis of MBC patients based on subtype, over time, are also important to differentiate.
Methods: The BC Cancer Breast Cancer Outcomes Unit (BCOU) database was utilized to identify patients referred to BC Cancer who were diagnosed with MBC during 3 time cohorts (cohort 1:2003-2005; cohort 2:2007-2009; cohort 3:2011-2013), to reflect changes in MBC treatment over these separate time periods. Baseline clinical and pathological criteria were compiled, in addition to adjuvant treatments received, as well as number of lines of treatment in the metastatic setting. OS was compared across time cohorts for all patients and then between subtypes using Kaplan-Meier survival curves.
Results: A total of 3,953 patients met the inclusion criteria, consisting of 2,440 (61.7%) estrogen-receptor positive (ER+), 778 (19.7%) HER2 positive and 542 (13.7%) triple-negative breast cancer (TNBC) patients. One hundred and ninety-three patients (4.9%) were unable to be subtyped and were therefore excluded from the analysis . A total of 2,205 (90.4%) ER+ patients received at least 1 line of systemic therapy, with 80.0% receiving at least 1 line of hormonal therapy. The median time on hormonal treatment was 8.9 months (range 0.03 - 156.7) for first-line and 6.1 months (range 0.1 – 173.3) for second-line. In the HER2+ group, 665 (85.5%) patients received at least 1 line of treatment, with a median of 2 lines of treatment (range 1-16). Median duration of anti-HER2 treatment was 6.7 months (range 0.03 - 163.8) with a median of 1 line of anti-HER2 directed treatment (range 1-5). For TNBC patients, 357 (65.9%) received at least 1 line of treatment, with a median of 2 (range 1-10). No significant differences in OS were observed between the 3 time cohorts, with a median overall survival (mOS) of 1.63 years, 1.37 years and 1.57 years in cohorts 1-3, respectively (p=0.12).When comparing across subtypes, the ER+ group faired best with a mOS of 1.96 years (95% CI 1.8-2.1), consistent across time cohorts (p=0.72). This was followed by the HER2+ group with a mOS of 1.53 years (95% CI 1.3-1.7), also consistent across time cohorts (p=0.31). The TNBC group faired worst, with a mOS of 0.67 years (95% CI 0.6-0.8) over time (p=0.87).
Conclusions: Despite advances in systemic therapy since the early 2000s, no meaningful improvements in overall survival were observed over time, regardless of subtype. It remains to be seen if developments since 2013 will lead to gains in overall survival for MBC patients, at a real life, population-based level.
1Chia SK, Speers CH, D'yachkova Y, et al. Cancer 2007;110:973-979.
Citation Format: LeVasseur N, Fiorino L, Speers CH, Aparicio M, Lohrisch C, Chia SK. Prognosis and survival in metastatic breast cancer – Ten years in review, a population-based analysis abstract. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P1-16-05.
Recent advances are enabling delivery of precision genomic medicine to cancer clinics. While the majority of approaches profile panels of selected genes or hotspot regions, comprehensive data ...provided by whole genome and transcriptome sequencing and analysis (WGTA) presents an opportunity to align a much larger proportion of patients to therapies.
Samples from 570 patients with advanced or metastatic cancer of diverse types enrolled in the Personalized OncoGenomics (POG) program underwent WGTA. DNA-based data, including mutations, copy number, and mutation signatures, were combined with RNA-based data, including gene expression and fusions, to generate comprehensive WGTA profiles. A multidisciplinary molecular tumour board used WGTA profiles to identify and prioritize clinically actionable alterations and inform therapy. Patient responses to WGTA-informed therapies were collected.
Clinically actionable targets were identified for 83% of patients, 37% of whom received WGTA-informed treatments. RNA expression data were particularly informative, contributing to 67% of WGTA-informed treatments; 25% of treatments were informed by RNA expression alone. Of a total 248 WGTA-informed treatments, 46% resulted in clinical benefit. RNA expression data were comparable to DNA-based mutation and copy number data in aligning to clinically beneficial treatments. Genome signatures also guided therapeutics including platinum, PARP inhibitors, and immunotherapies. Patients accessed WGTA-informed treatments through clinical trials (19%), off-label use (35%), and as standard therapies (46%) including those which would not otherwise have been the next choice of therapy, demonstrating the utility of genomic information to direct use of chemotherapies as well as targeted therapies.
Integrating RNA expression and genome data illuminated treatment options that resulted in 46% of treated patients experiencing positive clinical benefit, supporting the use of comprehensive WGTA profiling in clinical cancer care.
NCT02155621
•A prospective study of 570 patients used whole genome and transcriptome analysis (WGTA) for real-time treatment options•Of 248 WGTA-informed treatments, 46% resulted in clinical benefit to the patient•RNA expression information was as valuable as DNA-based information for selecting treatments with clinical benefit•Integrated data informs selection of standard-of-care therapies, clinical trial enrollment and off-label use•This study supports the use of whole genome and transcriptome analysis in clinical cancer care
The development of a hematopoietic reporter is crucial for determining the fate of lineages derived from cell-based therapies. A marking system will enable safer embryonic stem and induced ...pluripotent stem cell-based derivation of blood lineages and facilitate the development of efficient cellular reprogramming strategies based on direct fibroblast conversion. Here we report that the protein tyrosine phosphatase CD45 is an ideal candidate gene on which to base a hematopoietic reporter. CD45 regulatory elements were discovered by analyzing transcription factor chromatin occupancy (ChIP-seq) and promoter nuclease sensitivity (DNase-seq) to identify minimally sufficient sequences required for expression. After cloning the CD45 regulatory elements into an attenuated lentiviral backbone, we found that two transcriptional initiation regions were essential for high-level expression. Expressing CD45 promoters containing these regions and tethered to green fluorescent protein (GFP) in a primary B-cell differentiation assay and a transplantation model resulted in high levels of GFP in lymphoid, myeloid, and nucleated erythroid cells in mouse and human blood cell lineages. Moreover, GFP levels remained high 5 months after secondary transplantation, indicating persistence of the reporter. No CD45-driven GFP expression is observed after fibroblast or embryonic stem cell transduction. The GFP reporter is seen only after embryonic stem cells differentiate into hematopoietic cell progenitors and lineages, suggesting that this hematopoietic reporter system could be useful in validating potential autologous blood cell therapies.
Isolation increases activity in individuals of some species, whereas it decreases activity in individuals of other species. Furthermore, as the length of isolation increases, behavioral changes can ...become more pronounced. Here, we examined effects of short-term isolation on latencies for individuals to emerge from their shells in two species of terrestrial hermit crab (Coenobita rugosus and Coenobita brevimanus) over a 4-week period. Within each species, crabs were housed individually (isolate context) or socially in groups of four (social context). In each week, crabs were exposed to an emergence test, which measured the latency to emerge from the shell following a potentially threatening stimulus. We obtained a significant context × week interaction. Although socially housed crabs showed no change in emergence over the 4 weeks of the study, isolate crabs took longer to emerge from their shells as the period of isolation increased. Our study corroborates findings in other invertebrate species, as well as in vertebrate species, that isolation generally decreases activity levels and may increase fear levels, in individuals.
Abstract
Background: Adjuvant chemotherapy combining anthracyclines and taxanes for early stage breast cancer (ESBC) have demonstrated disease-free survival (DFS) and overall survival (OS) benefits. ...Among the 3rd generation regimens, 2 options have been favoured: FEC-Docetaxel (FECD) and AC-Paclitaxel (ACT). ACT may be delivered with dose-dense (ddACT) or weekly taxane scheduling (ddACWT), compared to traditional every 3-weekly (q3ACT) scheduling. Despite literature supporting both FECD and (dd)ACT regimens in the management of ESBC, no direct prospective trial has evaluated their comparative effectiveness.
Methods: A retrospective review of the BC Cancer Breast Cancer Outcomes Unit (BCOU) and the Alberta Health Services (AHS) databases was performed to identify patients with HER2 negative, stage 1-3 ESBC, who received adjuvant chemotherapy between 2007-2014. The primary endpoint was OS and the secondary endpoint was RFS, defined as freedom from local (invasive), regional or distant recurrence or breast cancer death. Outcome comparisons were made between FECD, ddACT/ddACWT and q3ACT using the Kaplan Meier method. Treatment arms were compared using a log-rank test for univariate analysis. A multivariate analysis was also conducted for OS comprising age, stage, grade, receptor status and type of chemotherapy received (FECD vs combined ACT group).
Results: A total of 4047 patients met inclusion criteria, including 2685 FECD, 1259 ddACT and 103 ACT. Median age was 53 (24-77) in the FECD group vs 52 (26-68) in the ddACT/ddACWT group and 58 (43-78) in the q3ACT group. The majority had stage 2 disease, 51.3%, 53.5% and 50.5% in the FECD, ddACT/ddACWT and q3ACT groups, respectively. Most were HR+, 84.5% in the FECD group vs 66.9% in both the ddACT/ddACWT and q3ACT groups. In the FECD group, 42.8% had a grade 2 tumour and 48.2% a grade 3 tumour vs 35.4% and 56.4% in the ddACT/ddACWT group and 35.0% and 58.3% in the q3ACT group. Lymphovascular invasion (LVI) was present in 40.7% of patients who received FECD vs 39.7% for ddACT/ddACWT and 26.2% for ACT. 5-year OS, for the FECD group was 90.3% (95%CI 89.1,91.4) vs 87.0% (95%CI 84.3,89.2) for the ddACT/ddACWT and 84.9% (95%CI 75.5,90.8) for the q3ACT groups, p=0.0907. 5-year RFS was 85.5% (95%CI 84.0-86.8) with FECD vs 84.4% (95% 81.9,86.6) for ddACT/ddACWT and 87.7% (95%CI 79.2,92.8) with q3ACT,p=0.4200. In multivariate analysis: age, stage and grade were significantly associated with OS whereas type of chemotherapy received (FECD vs ACT) was not (p=0.165). Finally, OS rates were compared across provinces and no significant differences were identified, 87.0% vs 88.0% (p=0.6294). Subgroup analyses by receptor type, comparing HR+ and TNBC are ongoing.
Conclusions: The use of FECD as compared to ACT based chemotherapy did not reveal significant differences in OS or RFS in this population-based study. Further, chemotherapy regimen was not associated with differences in overall survival, as compared to other well recognized prognostic factors. While the results were obtained from a retrospective analysis, conclusive prospective data is lacking. These results may therefore reassure physicians and patients alike on a comparable efficacy of these regimens in a real-life setting.
Citation Format: LeVasseur N, Veitch Z, Diocee RM, Gondara L, Cheung W, Khan O, Cossetti R, Gelmon KA, King K, Lupichuk S, Chia SK, Tang P, Simmons C. Real world outcomes of adjuvant FECD, ddACT and ACT for the treatment of early stage breast cancer - A multicenter retrospective analysis abstract. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P1-13-02.
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