12 research outputs found

    Protein kinase A antagonist inhibits β-catenin nuclear translocation, c-Myc and COX-2 expression and tumor promotion in ApcMin/+ mice

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>The adenomatous polyposis coli (APC) protein is part of the destruction complex controlling proteosomal degradation of β-catenin and limiting its nuclear translocation, which is thought to play a gate-keeping role in colorectal cancer. The destruction complex is inhibited by Wnt-Frz and prostaglandin E<sub>2 </sub>(PGE<sub>2</sub>) - PI-3 kinase pathways. Recent reports show that PGE<sub>2</sub>-induced phosphorylation of β-catenin by protein kinase A (PKA) increases nuclear translocation indicating two mechanisms of action of PGE<sub>2 </sub>on β-catenin homeostasis.</p> <p>Findings</p> <p>Treatment of <it>Apc</it><sup>Min/+ </sup>mice that spontaneously develop intestinal adenomas with a PKA antagonist (Rp-8-Br-cAMPS) selectively targeting only the latter pathway reduced tumor load, but not the number of adenomas. Immunohistochemical characterization of intestines from treated and control animals revealed that expression of β-catenin, β-catenin nuclear translocation and expression of the β-catenin target genes c-Myc and COX-2 were significantly down-regulated upon Rp-8-Br-cAMPS treatment. Parallel experiments in a human colon cancer cell line (HCT116) revealed that Rp-8-Br-cAMPS blocked PGE<sub>2</sub>-induced β-catenin phosphorylation and c-Myc upregulation.</p> <p>Conclusion</p> <p>Based on our findings we suggest that PGE<sub>2 </sub>act through PKA to promote β-catenin nuclear translocation and tumor development in <it>Apc</it><sup>Min/+ </sup>mice <it>in vivo</it>, indicating that the direct regulatory effect of PKA on β-catenin nuclear translocation is operative in intestinal cancer.</p

    De novo transcriptomic subtyping of colorectal cancer liver metastases in the context of tumor heterogeneity

    No full text
    Background Gene expression-based subtyping has the potential to form a new paradigm for stratified treatment of colorectal cancer. However, current frameworks are based on the transcriptomic profiles of primary tumors, and metastatic heterogeneity is a challenge. Here we aimed to develop a de novo metastasis-oriented framework. Methods In total, 829 transcriptomic profiles from patients with colorectal cancer were analyzed, including primary tumors, liver metastases, and non-malignant liver samples. High-resolution microarray gene expression profiling was performed of 283 liver metastases from 171 patients treated by hepatic resection, including multiregional and/or multi-metastatic samples from each of 47 patients. A single randomly selected liver metastasis sample from each patient was used for unsupervised subtype discovery by nonnegative matrix factorization, and a random forest prediction model was trained to classify multi-metastatic samples, as well as liver metastases from two independent series of 308 additional patients. Results Initial comparisons with non-malignant liver samples and primary colorectal tumors showed a highly variable degree of influence from the liver microenvironment in metastases, which contributed to inter-metastatic transcriptomic heterogeneity, but did not define subtype distinctions. The de novo liver metastasis subtype (LMS) framework recapitulated the main distinction between epithelial-like and mesenchymal-like tumors, with a strong immune and stromal component only in the latter. We also identified biologically distinct epithelial-like subtypes originating from different progenitor cell types. LMS1 metastases had several transcriptomic features of cancer aggressiveness, including secretory progenitor cell origin, oncogenic addictions, and microsatellite instability in a microsatellite stable background, as well as frequent RAS/TP53 co-mutations. The poor-prognostic association of LMS1 metastases was independent of mutation status, clinicopathological variables, and current subtyping frameworks (consensus molecular subtypes and colorectal cancer intrinsic subtypes). LMS1 was also the least heterogeneous subtype in comparisons of multiple metastases per patient, and tumor heterogeneity did not confound the prognostic value of LMS1. Conclusions We report the first large study of multi-metastatic gene expression profiling of colorectal cancer. The new metastasis-oriented subtyping framework showed potential for clinically relevant transcriptomic classification in the context of metastatic heterogeneity, and an LMS1 mini-classifier was constructed to facilitate prognostic stratification and further clinical testing

    Aspirin as secondary prevention in colorectal cancer liver metastasis (ASAC trial) : study protocol for a multicentre randomized placebo-controlled trial

    Get PDF
    Background: Colorectal cancer is one the most common cancers in the western world with increasing incidence. Approximately 50% of the patients develop liver metastases. Resection of liver metastases is the treatment of choice although almost half of the resected patients get recurrence in the liver. Methods: The ASAC trial is a Scandinavian, multicentre, double-blinded, randomized, placebo-controlled study to determine whether adjuvant treatment with low-dose aspirin (acetylsalicylic acid (ASA)) can improve disease-free survival in patients treated for colorectal cancer liver metastases (CRCLM). Up to 800 patients operated for CRCLM will be randomized to Arm#1 ASA 160 mg once daily or Arm#2 Placebo, for a period of 3 years or until disease recurrence. The patients will be recruited at all major hepatobiliary surgical units in Norway, Sweden and Denmark and have follow-up according to standard of care and the National Guidelines. Discussion: The ASAC trial will be the first clinical interventional trial to assess the potential beneficial role of ASA in recurrence of CRCLM and survival. ASA is an inexpensive, well-tolerated and easily accessible drug that will be highly potential as adjuvant drug in secondary prevention of CRCLM if the study shows a beneficial effect. We will also determine the effect of ASA as adjuvant treatment on Health-Related Quality of Life and the cost-effectiveness.

    RAS Mutation Clinical Risk Score to Predict Survival After Resection of Colorectal Liver Metastases

    No full text
    OBJECTIVE:: To determine the impact of RAS mutation status on the traditional clinical score (t-CS) to predict survival after resection of colorectal liver metastases (CLM). BACKGROUND:: The t-CS relies on the following factors: primary tumor nodal status, disease-free interval, number and size of CLM, and carcinoembryonic antigen level. We hypothesized that the addition of RAS mutation status could create a modified clinical score (m-CS) that would outperform the t-CS. METHODS:: Patients who underwent resection of CLM from 2005 through 2013 and had RAS mutation status and t-CS factors available were included. Multivariate analysis was used to identify prognostic factors to include in the m-CS. Log-rank survival analyses were used to compare the t-CS and the m-CS. The m-CS was validated in an international multicenter cohort of 608 patients. RESULTS:: A total of 564 patients were eligible for analysis. RAS mutation was detected in 205 (36.3%) of patients. On multivariate analysis, RAS mutation was associated with poor overall survival, as were positive primary tumor lymph node status and diameter of the largest liver metastasis &gt;50?mm. Each factor was assigned 1 point to produce a m-CS. The m-CS accurately stratified patients by overall and recurrence-free survival in both the initial patient series and validation cohort, whereas the t-CS did not. CONCLUSIONS:: Modifying the t-CS by replacing disease-free interval, number of metastases, and CEA level with RAS mutation status produced an m-CS that outperformed the t-CS. The m-CS is therefore a simple validated tool that predicts survival after resection of CLM

    Benchmarks and Geographic Differences in Gallbladder Cancer Surgery: An International Multicenter Study

    No full text
    BackgroundHigh-quality surgery plays a central role in the delivery of excellent oncologic care. Benchmark values indicate the best achievable results. We aimed to define benchmark values for gallbladder cancer (GBC) surgery across an international population.Patients and MethodsThis study included consecutive patients with GBC who underwent curative-intent surgery during 2000-2021 at 13 centers, across seven countries and four continents. Patients operated on at high-volume centers without the need for vascular and/or bile duct reconstruction and without significant comorbidities were chosen as the benchmark group.ResultsOf 906 patients who underwent curative-intent GBC surgery during the study period, 245 (27%) were included in the benchmark group. These were predominantly women (n = 174, 71%) and had a median age of 64 years (interquartile range 57-70 years). In the benchmark group, 50 patients (20%) experienced complications within 90 days after surgery, with 20 patients (8%) developing major complications (Clavien-Dindo grade &gt;= IIIa). Median length of postoperative hospital stay was 6 days (interquartile range 4-8 days). Benchmark values included &gt;= 4 lymph nodes retrieved, estimated intraoperative blood loss &lt;= 350 mL, perioperative blood transfusion rate &lt;= 13%, operative time &lt;= 332 min, length of hospital stay &lt;= 8 days, R1 margin rate &lt;= 7%, complication rate &lt;= 22%, and rate of grade &gt;= IIIa complications &lt;= 11%.ConclusionsSurgery for GBC remains associated with significant morbidity. The availability of benchmark values may facilitate comparisons in future analyses among GBC patients, GBC surgical approaches, and centers performing GBC surgery
    corecore