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Adenoid cystic carcinoma (ACC) of the breast with a predominant solid pattern is difficult to diagnose with certainty and differentiate from more common triple-negative breast cancers (TNBCs) of basal-phenotype. To better characterize solid ACC, we performed a clinical, morphological, immunohistochemical, and molecular comparative analysis of 33 ACCs of the breast comprising 17 solid variant ACCs and 16 conventional ACCs. Solid ACCs displayed basaloid morphology with an exclusive or predominant epithelial cell population associated with decreased myoepithelial differentiation, while demonstrating MYB protein overexpression similar to the more common type of ACC. Strong and diffuse MYB expression by immunochemistry was observed in 14/17 (82%) of solid ACCs while MYB rearrangements were detected by break apart fluorescence in situ hybridization (FISH) in only 3/16 (19%) of solid ACCs. Conversely, weak MYB immunohistochemical expression was observed in only 7/204 (3%) of TNBC. Solid ACCs displayed a transcriptomic profile distinct from conventional ACCs with 549 genes showing a highly significant differential expression between conventional and solid ACC [false discovery rate (FDR) |1|]. EnrichR and Kegg Pathway analyses identified PI3K-Akt and focal adhesion signaling pathways as significantly overexpressed in conventional ACCs compared with solid ACCs which significantly overexpressed the nitrogen metabolism pathway. CREBBP mutations and NOTCH activating gene mutations were only present in solid ACCs, concerning 5/16 (31%) of cases for each gene. Tumors with NOTCH activating mutations displayed a strong diffuse nuclear NICD1 staining, an established marker of Notch pathway activation. Solid ACCs also differed from basal-type TNBC, with fewer TP53 mutations and a more stable genomic profile on array comparative genomic hybridization (CGH). In summary, solid-type ACC of the breast is a distinct molecular entity within the ACC family and is different from common basal-type TNBC. MYB is a diagnostically useful biomarker of solid ACC and NOTCH could be a novel potential therapeutic target in 30% of cases.

TP53 has a crucial role in the DNA damage response. We therefore tested the hypothesis that taxanes confer a greater advantage than do anthracyclines on breast cancers with mutated TP53 than in those with wild-type TP53.In an open-label, phase 3 study, women (age71 years) with locally advanced, inflammatory, or large operable breast cancers were randomly assigned in a 1:1 ratio to either a standard anthracycline regimen (six cycles of intravenous fluorouracil 500 mg/m², epirubicin 100 mg/m², and cyclophosphamide 500 mg/m² every 21 days [FEC100], or fluorouracil 600 mg/m², epirubicin 75 mg/m², cyclophosphamide 900 mg/m² [tailored FEC] starting on day 1 and then every 21 days) or a taxane-based regimen (three cycles of docetaxel 100 mg/m², intravenously infused over 1 h on day 1 every 21 days, followed by three cycles of intravenous epirubicin 90 mg/m² and docetaxel 75 mg/m² on day 1 every 21 days [T-ET]) at 42 centres in Europe. Randomisation was by use of a minimisation method that stratified patients by institution and initial tumour stage. The primary endpoint was progression-free survival (PFS) according to TP53 status. Analysis was by intention to treat. This is the final analysis of this trial. The study is registered with ClinicalTrials.gov, number NCT00017095.928 patients were enrolled in the FEC group and 928 in the T-ET group. TP53 status was not assessable for 183 (20%) patients in the FEC group and 204 (22%) patients in the T-ET group mainly because of low tumour-cell content in the biopsy. 361 primary endpoint events were recorded in the FEC group and 314 in the T-ET group. In patients with TP53-mutated tumours, 5-year PFS was 59·5% (95% CI 53·4-65·1) in the T-ET group (n=326) and 55·3% (49·2-60·9) in the FEC group (n=318; hazard ratio 0·84, 98% CI 0·63-1·14; p=0·17). In patients with TP53 wild-type tumours, 5-year PFS was 66·8% (95% CI 61·4-71·6) in the T-ET group (n=398) and 64·7% (59·6-69·4) in the FEC group (n=427; 0·89, 98% CI 0·68-1·18; p=0·35). For all patients, irrespective of TP53 status, 5-year PFS was 65·1% (95% CI 61·6-68·3) in the T-ET group and 60·8% (57·3-64·2) in the FEC group (0·85, 98% CI 0·71-1·02; p=0·035). At the sites using FEC100 versus T-ET, the most common grade 3 or 4 adverse events were febrile neutropenia (75 [9%] of 803 vs 173 [21%] of 809, respectively), and neutropenia (653 [81%] vs 730 [90%], respectively). At the sites using tailored FEC versus T-ET, the most common grade 3 or 4 adverse events were febrile neutropenia (ten [8%] of 118 vs 26 [22%] of 116, respectively), and neutropenia (100 [85%] vs 115 [99%], respectively). Two patients died of toxicity during or within 30 days of chemotherapy completion and without disease relapse (one in each group).Although TP53 status was prognostic for overall survival, it was not predictive of preferential sensitivity to taxanes. TP53 status tested by use of the yeast assay in this patient population cannot be used to select patients for an anthracycline-based chemotherapy versus a taxane-based chemotherapy.US National Cancer Institute, La Ligue Nationale Contre le Cancer, European Union, Pharmacia, and Sanofi-Aventis.

Markers that predict the sensitivity of tumours to chemotherapy must address two questions: (a) which tumours are more likely to respond to chemotherapy? and (b) what is the optimal chemotherapy regimen for a specific tumour or group of tumours? To answer these questions will require markers of general chemosensitivity and drug-specific chemosensitivity, respectively. Beyond these fundamental questions lies an important practical question: are the predictive markers in the current literature ready for routine clinical use? The focus of this paper is to address this practical question. We will first review retrospective trials that have reported promising chemotherapy signatures, presenting in a comprehensive manner for the non bio-informatician the different methods used so far. In addition, we will summarise prospective trials (either ongoing or under development) designed to test the multigene classifiers currently thought to predict chemosensitivity. Finally, we will discuss why microarray studies have so far failed to identify new targets, and how we might be able to improve on these results through large-scale genotyping of tumours.

We have used a yeast p53 functional assay to study induction of mutations in the p53 tumor suppressor gene by nitric oxide and cytosine methylation. The yeast assay identifies only biologically important p53 mutations. p53 cDNA was treated with the nitric oxide donor sydnonimine, PCR-amplified and transfected into yeast. Sydnonimine produced a significant, dose-dependent increase in C:G→A:T transversions. Many important p53 mutational hotspots are postulated to arise by deamination of methylCpG in tumors. We therefore examined nitric oxide induction of mutations in p53 cDNA methylated by PCR-mediated substitution of 5-methylcytosine for cytosine or by treatment with the SssI CpG methylase. Both methylation procedures increased the baseline mutation rate, and nitric oxide treatment produced a further increase in mutation yield. Sequence analysis showed that methylation alone led to C:G→T:A transitions, whereas nitric oxide treatment simply produced more C:G→A:T transversions. Thus the most important factor in C:G→T:A transition at CpG sites identified in this experimental system is cytosine methylation, consistent with spontaneous conversion of 5-methylcytosine to thymine by deamination.

Reference EPFL-CONF-172479View record in Web of Science Record created on 2011-12-16, modified on 2017-05-12

Top of pageAbstract We developed oncolytic adenoviruses that selectively target cancer cells with active |[beta]|-catenin signaling. To achieve this, Tcf promoters were inserted into early virus promoters E1A, E1B and E4. The virus (Ad5Tcf) demonstrated 1000-fold selectivity to tumor cells in vitro, but only a limited efficacy in vivo upon intravenous administration. We then used a range of approaches to increase in vivo efficacy of this virus. First, RGD motif was inserted into the fiber HI loop to improve infection of cancer cells. This modification increased overall efficacy of the virus and allowed infection of cell lines that did not express the natural CAR receptor. Next, we used combination therapy with m-TOR inhibitor, RAD001, which mainly acts as anti-angiogenic drug, to slow down tumor growth in a way that would not adversely affect the virus replication. This combined treatment with 10E11 particles of intravenous Ad5Tcf or Ad5Tcf-RGD virus and 5 mg/kg/day RAD001 was significantly better than any of the agents alone and could almost completely stop growth even of the most aggressive tumor xenografts. In addition, RAD001 is now undergoing phase II clinical trials as an immunosuppressant, and thus has a capability of limiting immune response to oncolytic adenoviruses. In our experiment, 5 mg/kg/day of RAD001 could completely abolish primary antibody response to adenovirus in immunocompetent mice. To further increase efficacy of the Tcf-retargeted virus, we expressed the Escherichia coli nitroreductase nfsB gene from an internal ribosome entry site (IRES) in the adenovirus L5 major late transcript. This enzyme converts prodrug CB1954 into a toxic derivative. The virus (Ad5Tcf-NTR) expressed nitroductase late with high specificity to cancer cells. This modification has markedly increased virus efficacy in vitro. In vivo, however, the gain from the enzyme-prodrug scheme was only marginal when used alone or in combination with RAD001. As we demonstrated, virus distribution in mouse xenografts was very uneven at late terms, and massively infected and dying tumor regions were separated by necrotic masses and connective tissue streaks that are impassable to the virus. Even minor isolated uninfected tumor fragments then quickly overgrew the killed part. As a conclusion, successful virus therapy of tumors would require further effort to improve virus delivery to achieve even infection and enhanced virus spread within the tumor.

In virtually all colon cancer cell lines |[beta]|-catenin is activated. The target genes of |[beta]|-catenin are activated through the interaction of |[beta]|-catenin with the transcription factor TCF. Previously in our laboratory conditionally replicating adenoviruses with TCF sites in the early viral promoters were constructed. We inserted TCF sites into the E1A, E1B and E4 promoters. This virus, vKH1, shows 1000 fold selectivity for colon cancer cell lines compared to wild type Ad5.

In virtually all colon cancer cell lines b-catenin is activated. The target genes of b-catenin are activated through interaction of b-catenin with the transcription factor TCF. Previously in our laboratory conditionally replicating adenoviruses with TCF binding sites in the early viral promoters were constructed. We inserted TCF sites into the E1A, E1B and E4 early promoters of the wild type adenovirus. This virus, vKH1, shows 1000-fold selectivity for colon cancer cells compared to wild type Ad5.