[Show abstract][Hide abstract] ABSTRACT: STUDY OBJECTIVES
To compare breast cancer metastases between obese and nonobese women and to evaluate the effect of first-line metastatic chemotherapy in each group.
A retrospective study was performed in an educational institute in Ireland. The study consisted of two parts: the first part was a comparative analysis of metastases development in obese (arm A) and nonobese patients (arm B). The second part was a comparison between both arms in relation to their response to first-line metastatic chemotherapy and their survival data.
Between 2009 and 2014, we reviewed 118 patients with metastatic breast cancer. All the patients fulfilled our inclusion criteria. In all, 48% of patients were obese and 52% were nonobese. There were no statistically significant differences between the two groups. For arms A and B, the median interval between initial cancer diagnosis and distant metastases development (distant metastases-free survival) was 5.8 versus 7.6 years, respectively (Pvalue 0.04). Earlier visceral (liver and lung) metastases were observed in obese compared to nonobese women (Pvalues were 0.05 and 0.04, respectively). The most commonly used chemotherapy was weekly paclitaxel. Our treatments showed significantly better treatment response and better survival results in nonobese women than in obese ones, who were premenopausal with performance state 2, pathological grade 3, and four or more positive lymph nodes.
Obesity is linked with visceral metastases development, especially lung and liver metastases. Furthermore, first-line metastatic chemotherapy achieved better results in nonobese patients.
Preview · Article · Nov 2015 · Clinical Medicine Insights: Oncology
[Show abstract][Hide abstract] ABSTRACT: The 21-gene test is a validated multi-gene diagnostic test that predicts chemotherapy (CT) benefit in oestrogen receptor positive (ER+), lymph node-negative (N0) breast cancer (BC) patients (pts). Ireland was the first public health care system to reimburse this test in Europe. Study objectives were to assess the impact of this test on decision-making and to analyse the economic impact of testing. Between October 2011 and February 2013, a national, retrospective, cross-sectional observational study of ER+, N0 BC pts tested with the 21-gene test was conducted. Surveyed breast medical oncologists, provided the assumption for the decision impact analysis that grade (G) 1 pts would not have received CT before testing and G2/3 pts would have received CT before testing. Descriptive statistical analyses were performed. 592 pts were identified; Low, intermediate and high recurrence score were identified in 53, 36 and 10 % pts, respectively. 384 (70 %) pts had G2, 129 (22 %) G3 and 76 (13 %) G1 tumours. Post testing, 345 pts (59 %) experienced a change in CT decision; 339 changed to hormone therapy alone and 6 advised to receive CT. 172 (30 %) pts received CT, 12 (3.9 %) of pts with low scores, 108 (50.9 %) of intermediate risk and 50 (90.9 %) of pts with high risk scores. Net reduction in CT use was 58 % and net savings achieved were €793,565. Since public reimbursement, the introduction of the 21-gene test has resulted in a significant reduction in chemotherapy administration and cost savings for the Irish public healthcare system.
No preview · Article · Sep 2015 · Breast Cancer Research and Treatment
[Show abstract][Hide abstract] ABSTRACT: Background: Somatic mutations in the 4 HER family genes (EGFR, HER2, 3, 4) occur in HER2-positive breast cancer (HER2+ BC). (Cancer Genome Atlas N. Comprehensive molecular portraits of human breast tumors. Nature 2012;490(7418): 61-70.) We investigated their frequency in a large set of HER2+ BCs and their therapeutic relevance.
Methods: Tumors from 246 HER2+ BC patients who received adjuvant trastuzumab-based therapy after surgery were reviewed by a pathologist for tumor content. DNA from 48 matched normal and cancerous samples was sequenced using the Agilent kinome library and a MiSeq. Somatic HER gene mutations identified in this way had their frequency determined by Sequenom MassArray (n=246). HER gene mutations were correlated with patient outcomes. Constructs of 2 hotspot HER3/4 mutations were created and transfected into BT474, HCC1569 and HCC1954 cells. Doubling time, proliferation, Boyden chamber assays and RPPA were used to determine effects of mutations on cell growth, invasion, signalling and response to HER2-targeted therapies.
Results: 12 somatic deleterious mutually exclusive mutations in the kinase and furin like domains of the 4 HER genes (3 EGFR, 2 HER2, 2 HER3, 5 HER4 mutations) were identified in 6.5 % of HER2+ BCs including 2 hotspot mutations in HER3/4. HER gene mutations did not impact OS or RFS after adjuvant trastuzumab. HER3/4 hotspot mutations increased doubling rates in vitro and induced resistance to anti-HER2/EGFR TKIs (Table) but not trastuzumab. Transfected cells were sensitive to the PI3K inhibitor copanlisib and copanlisib also restored sensitivity to these TKIs in these cell lines.
Conclusions: HER family mutations occur in 6.5% of HER2+BC and affect tumour growth and response to HER2-targeted therapies.
[Show abstract][Hide abstract] ABSTRACT: Because of advances in targeted therapies, the clinical evaluation of cutaneous melanoma is increasingly based on a combination of traditional histopathology and molecular pathology. Therefore, it is necessary to expand our knowledge of the molecular events that accompany the development and progression of melanoma to optimize clinical management. The central objective of this study was to increase our knowledge of the mutational events that complement melanoma progression. High-throughput genotyping was adapted to query 159 known single nucleotide mutations in 33 cancer-related genes across two melanoma cohorts from Ireland (n=94) and Belgium (n=60). Results were correlated with various clinicopathological characteristics. A total of 23 mutations in 12 genes were identified, that is - BRAF, NRAS, MET, PHLPP2, PIK3R1, IDH1, KIT, STK11, CTNNB1, JAK2, ALK, and GNAS. Unexpectedly, we discovered significant differences in BRAF, MET, and PIK3R1 mutations between the cohorts. That is, cases from Ireland showed significantly lower (P<0.001) BRAF mutation rates (19%) compared with the mutation frequency observed in Belgian patients (43%). Moreover, MET mutations were detected in 12% of Irish cases, whereas none of the Belgian patients harbored these mutations, and Irish patients significantly more often (P=0.027) had PIK3R1-mutant (33%) melanoma versus 17% of Belgian cases. The low incidence of BRAF-mutant melanoma among Irish patients was confirmed in five independent Irish cohorts, and in total, only 165 of 689 (24%) Irish cases carried mutant BRAF. Together, our data show that melanoma-driving mutations vary by demographic area, which has important implications for the clinical management of this disease.
Full-text · Article · Mar 2015 · Melanoma Research
[Show abstract][Hide abstract] ABSTRACT: Inflammatory myofibroblastic tumours (IMTs) are rare sarcomas that were first described in the lung. They are composed of myofibroblastic mesenchymal spindle cells accompanied by an inflammatory infiltrate of plasma cells. Complete resection is the treatment of choice. There is currently no standard treatment for inoperable or recurrent disease. Expression of ALK protein triggered by ALK gene rearrangement at chromosome 2p23 has been found in 36%-60% of IMTs.
We report a rapid early response to crizotinib as neoadjuvant therapy, enabling surgical excision of a large ALK-translocated IMT, which resulted in complete disease clearance. To the best of our knowledge, this is the first case in the literature of a patient with IMT in whom crizotinib was used successfully in the neoadjuvant or curative setting.
[Show abstract][Hide abstract] ABSTRACT: Approximately 20 % of human breast cancers (BC) overexpress HER2 protein, and HER2-positivity is associated with a worse prognosis. Although HER2-targeted therapies have significantly improved outcomes for HER2-positive BC patients, resistance to trastuzumab-based therapy remains a clinical problem. In order to better understand resistance to HER2-targeted therapies in HER2-positive BC, it is necessary to examine HER family signalling as a whole. An extensive literature search was carried out to critically assess the current knowledge of HER family signalling in HER2-positive BC and response to HER2-targeted therapy. Known mechanisms of trastuzumab resistance include reduced receptor-antibody binding (MUC4, p95HER2), increased signalling through alternative HER family receptor tyrosine kinases (RTK), altered intracellular signalling involving loss of PTEN, reduced p27kip1, or increased PI3K/AKT activity and altered signalling via non-HER family RTKs such as IGF1R. Emerging strategies to circumvent resistance to HER2-targeted therapies in HER2-positive BC include co-targeting HER2/PI3K, pan-HER family inhibition, and novel therapies such as T-DM1. There is evidence that immunity plays a key role in the efficacy of HER-targeted therapy, and efforts are being made to exploit the immune system in order to improve the efficacy of current anti-HER therapies. With our rapidly expanding understanding of HER2 signalling mechanisms along with the repertoire of HER family and other targeted therapies, it is likely that the near future holds further dramatic improvements to the prognosis of women with HER2-positive BC.
Full-text · Article · Dec 2014 · Breast Cancer Research and Treatment
[Show abstract][Hide abstract] ABSTRACT: The PI3K pathway is a key mechanism of trastuzumab resistance, but early attempts to indirectly target this pathway with mTOR inhibitors have had limited success. We present the results of a preclinical study of the selective alpha/delta isoform dominant PI3K inhibitor BAY 80-6946 tested alone and in combination with HER2-targeted therapies in HER2-positive cell lines, including models with acquired resistance to trastuzumab and/or lapatinib. A panel of HER2-positive breast cancer cells were profiled for their mutational status using Sequenom MassARRAY, PTEN status by Western blot, and anti-proliferative response to BAY 80-6946 alone and in combination with the HER2-targeted therapies trastuzumab, lapatinib and afatinib. Reverse phase protein array was used to determine the effect of BAY 80-6946 on expression and phosphorylation of 68 proteins including members of the PI3K and MAPK pathways. The Boyden chamber method was used to determine if BAY 80-6946 affected cellular invasion and migration. BAY 80-6946 has anti-proliferative and anti-invasive effects when used alone in our panel of cell lines (IC50s 3.9–29.4 nM). BAY 80-6946 inhibited PI3K signalling and was effective in cells regardless of their PI3K, P53 or PTEN status. The combination of HER2-targeted therapies and BAY 80-6946 inhibited growth more effectively than either therapy used alone (with clear synergism in many cases), and can restore sensitivity to trastuzumab and lapatinib in cells with acquired resistance to either trastuzumab and/or lapatinib. The addition of BAY 80-6946 to HER2-targeted therapy could represent an improved treatment strategy for patients with refractory metastatic HER2-positive breast cancer, and should be considered for clinical trial evaluation.
Full-text · Article · Dec 2014 · Breast Cancer Research and Treatment
[Show abstract][Hide abstract] ABSTRACT: Unlabelled:
In locally advanced rectal cancer, neoadjuvant chemoradiotherapy is performed prior to surgery to downstage the tumour. Thirty to 40 % of patients do not respond. Defects in apoptotic machinery lead to therapy resistance; however, to date, no study quantitatively assessed whether B cell lymphoma 2 (BCL2)-dependent regulation of mitochondrial apoptosis, effector caspase activation downstream of mitochondria or a combination of both predicts patient responses. In a cohort of 20 rectal cancer patients, we performed protein profiling of tumour tissue and employed validated ordinary differential equation-based systems models of apoptosis signalling to calculate the ability of cancer cells to undergo apoptosis. Model outputs were compared to clinical responses. Systems modelling of BCL2-signalling predicted patients in the poor response group (p = 0.0049). Systems modelling also demonstrated that rectal cancers depended on BCL2 rather than B cell lymphoma-extra large (BCL(X)L) or myeloid cell leukemia 1 (MCL1) for survival, suggesting that poor responders may benefit from therapy with selective BCL2 antagonists. Dynamic modelling of effector caspase activation could not stratify patients with poor response and did not further improve predictive power. We deliver a powerful patient stratification tool identifying patients who will likely not benefit from neoadjuvant chemoradiotherapy and should be prioritised for surgical resection or treatment with BCL2 antagonists.
Modelling BCL2-family proteins identifies patients unresponsive to therapy. Caspase activation downstream of mitochondria cannot identify these patients. Rectal tumours of poor responders are BCL2- but not BCL-XL-dependent. DR_MOMP allows clinicians to identify patients who would not benefit from therapy. DR_MOMP is also a useful patient stratification tool for BCL2 antagonists.
Full-text · Article · Nov 2014 · Journal of Molecular Medicine
[Show abstract][Hide abstract] ABSTRACT: Ovarian cancer has the lowest survival rate of all gynaecologic cancers and is characterised by a lack of early symptoms and frequent late stage diagnosis. There is a paucity of robust molecular markers that are independent of and complementary to clinical parameters such as disease stage and tumour grade.
We have developed a user-friendly, web-based system to evaluate the association of genes/miRNAs with outcome in ovarian cancer. The OvMark algorithm combines data from multiple microarray platforms (including probesets targeting miRNAs) and correlates them with clinical parameters (e.g. tumour grade, stage) and outcomes (disease free survival (DFS), overall survival). In total, OvMark combines 14 datasets from 7 different array platforms measuring the expression of ~17,000 genes and 341 miRNAs across 2,129 ovarian cancer samples.
To demonstrate the utility of the system we confirmed the prognostic ability of 14 genes and 2 miRNAs known to play a role in ovarian cancer. Of these genes, CXCL12 was the most significant predictor of DFS (HR = 1.42, p-value = 2.42x10−6). Surprisingly, those genes found to have the greatest correlation with outcome have not been heavily studied in ovarian cancer, or in some cases in any cancer. For instance, the three genes with the greatest association with survival are SNAI3, VWA3A and DNAH12.
OvMark is a powerful tool for examining putative gene/miRNA prognostic biomarkers in ovarian cancer (available at http://glados.ucd.ie/OvMark/index.html). The impact of this tool will be in the preliminary assessment of putative biomarkers in ovarian cancer, particularly for research groups with limited bioinformatics facilities.
[Show abstract][Hide abstract] ABSTRACT: Angiogenesis or new vessel formation is essential for tumour growth and progression. Therefore, targeting angiogenesis has been an attractive strategy in the treatment ofcancer. Bevacizumab is a recombinant humanized monoclonal IgG1 antibody thattargets vascular endothelial growth factor-A (VEGF-A) - a key molecular player inangiogenesis. Bevacizumumab has shown clinical efficacy in phase III clinical trials inseveral advanced solid malignancies. The clinical efficacy of bevacizumumab isprimarily due to its antiangiogenic effects; however, there are direct antitumor effectsand immunomodulatory effects. Enhancing the immune system to restore itsantitumour activity has been utilized successfully in clinical setting. In this article we willdiscuss the possible immunomodulatory effects of the most clinically usedantiangiogenic agent; bevacizumumab.
Full-text · Article · Oct 2014 · Cancer Microenvironment
[Show abstract][Hide abstract] ABSTRACT: Introduction
Peroxiredoxin-1 (PRDX1) is a multifunctional protein, acting as a hydrogen peroxide (H2O2) scavenger, molecular chaperone and immune modulator. Although differential PRDX1 expression has been described in many tumors, the potential role of PRDX1 in breast cancer remains highly ambiguous. Using a comprehensive antibody-based proteomics approach, we interrogated PRDX1 protein as a putative biomarker in estrogen receptor (ER)-positive breast cancer.
An anti-PRDX1 antibody was validated in breast cancer cell lines using immunoblotting, immunohistochemistry and reverse phase protein array (RPPA) technology. PRDX1 protein expression was evaluated in two independent breast cancer cohorts, represented on a screening RPPA (n = 712) and a validation tissue microarray (n = 498). In vitro assays were performed exploring the functional contribution of PRDX1, with oxidative stress conditions mimicked via treatment with H2O2, peroxynitrite, or adenanthin, a PRDX1/2 inhibitor.
In ER-positive cases, high PRDX1 protein expression is a biomarker of improved prognosis across both cohorts. In the validation cohort, high PRDX1 expression was an independent predictor of improved relapse-free survival (hazard ratio (HR) = 0.62, 95% confidence interval (CI) = 0.40 to 0.96, P = 0.032), breast cancer-specific survival (HR = 0.44, 95% CI = 0.24 to 0.79, P = 0.006) and overall survival (HR = 0.61, 95% CI = 0.44 to 0.85, P = 0.004). RPPA screening of cancer signaling proteins showed that ERα protein was upregulated in PRDX1 high tumors. Exogenous H2O2 treatment decreased ERα protein levels in ER-positive cells. PRDX1 knockdown further sensitized cells to H2O2- and peroxynitrite-mediated effects, whilst PRDX1 overexpression protected against this response. Inhibition of PRDX1/2 antioxidant activity with adenanthin dramatically reduced ERα levels in breast cancer cells.
PRDX1 is shown to be an independent predictor of improved outcomes in ER-positive breast cancer. Through its antioxidant function, PRDX1 may prevent oxidative stress-mediated ERα loss, thereby potentially contributing to maintenance of an ER-positive phenotype in mammary tumors. These results for the first time imply a close connection between biological activity of PRDX1 and regulation of estrogen-mediated signaling in breast cancer.
Full-text · Article · Jul 2014 · Breast cancer research: BCR