Peter A. van Dam

mRNA and microRNA expression profiles in circulating tumor cells and primary tumors of metastatic breast cancer patients

Purpose: Molecular characterization of circulating tumor cells (CTC) holds great promise. Unfortunately, routinely isolated CTC fractions currently still contain contaminating leukocytes, which makes CTC-specific molecular characterization extremely challenging. In this study, we determined mRNA and microRNA (miRNA) expression of potentially CTC-specific genes that are considered to be clinically relevant in breast cancer. Experimental Design: CTCs were isolated with the epithelial cell adhesion molecule–based CellSearch Profile Kit. Selected genes were measured by real-time reverse transcriptase PCR in CTCs of 50 metastatic breast cancer patients collected before starting first-line systemic therapy in blood from 53 healthy blood donors (HBD) and in primary tumors of 8 of the patients. The molecular profiles were associated with CTC counts and clinical parameters and compared with the profiles generated from the corresponding primary tumors. Results: We identified 55 mRNAs and 10 miRNAs more abundantly expressed in samples from 32 patients with at least 5 CTCs in 7.5 mL of blood compared with samples from 9 patients without detectable CTCs and HBDs. Clustering analysis resulted in 4 different patient clusters characterized by 5 distinct gene clusters. Twice the number of patients from cluster 2 to 4 had developed both visceral and nonvisceral metastases. Comparing transcript levels in CTCs with those measured in corresponding primary tumors showed clinically relevant discrepancies in estrogen receptor and HER2 levels. Conclusions: Our study shows that molecular profiling of low numbers of CTCs in a high background of leukocytes is feasible and shows promise for further studies on the clinical relevance of molecular characterization of CTCs. Clin Cancer Res; 17(11); 3600–18. ©2011 AACR.

Expression profiling of cancerous and normal breast tissues identifies microRNAs that are differentially expressed in serum from patients with (metastatic) breast cancer and healthy volunteers.

IntroductionMicroRNAs (miRNAs) are a group of small noncoding RNAs involved in the regulation of gene expression. As such, they regulate a large number of cellular pathways, and deregulation or altered expression of miRNAs is associated with tumorigenesis. In the current study, we evaluated the feasibility and clinical utility of circulating miRNAs as biomarkers for the detection and staging of breast cancer.MethodsmiRNAs were extracted from a set of 84 tissue samples from patients with breast cancer and eight normal tissue samples obtained after breast-reductive surgery. After reverse transcription and preamplification, 768 miRNAs were profiled by using the TaqMan low-density arrays. After data normalization, unsupervised hierarchical cluster analysis (UHCA) was used to investigate global differences in miRNA expression between cancerous and normal samples. With fold-change analysis, the most discriminating miRNAs between both tissue types were selected, and their expression was analyzed on serum samples from 20 healthy volunteers and 75 patients with breast cancer, including 16 patients with untreated metastatic breast cancer. miRNAs were extracted from 200 μl of serum, reverse transcribed, and analyzed in duplicate by using polymerase chain reaction (qRT-PCR).ResultsUHCA showed major differences in miRNA expression between tissue samples from patients with breast cancer and tissue samples from breast-reductive surgery (P < 0.0001). Generally, miRNA expression in cancerous samples tends to be repressed when compared with miRNA expression in healthy controls (P = 0.0685). The four most discriminating miRNAs by fold-change (miR-215, miR-299-5p, miR-411, and miR-452) were selected for further analysis on serum samples. All miRNAs at least tended to be differentially expressed between serum samples from patients with cancer and serum samples from healthy controls (miR-215, P = 0.094; miR-299-5P, P = 0.019; miR-411, P = 0.002; and miR-452, P = 0.092). For all these miRNAs, except for miR-452, the greatest difference in expression was observed between serum samples from healthy volunteers and serum samples from untreated patients with metastatic breast cancer.ConclusionsOur study provides a basis for the establishment of miRNAs as biomarkers for the detection and eventually staging of breast cancer through blood-borne testing. We identified and tested a set of putative biomarkers of breast cancer and demonstrated that altered levels of these miRNAs in serum from patients with breast cancer are particularly associated with the presence of metastatic disease.

The importance of biological factors (bcl-2, bax, p53, PCNA, MI, HPV and angiogenesis) in invasive cervical cancer

OBJECTIVEnThe present study was designed to analyse the relationship between apoptosis related proteins (bcl-2 and bax), tumour suppressor protein p53, proliferation markers (PCNA and mitotic index), human papillomavirus (HPV) and angiogenesis in cervical cancer and their impact on clinical outcome.nnnSTUDY DESIGNnTumours from 111 patients were assessed by immunohistochemistry for the expression of bcl-2, bax, p53 and PCNA, by PCR for the presence of HPV-DNA, for the quantification of the mitotic index and the microvessel density (CD 31). The results were correlated with various histopathologic characteristics and survival.nnnRESULTSnThe multiple Coxs regression analysis for overall survival of all prognostic variables gave as best model: bcl-2 (P<0.001), lymphovascular permeation (P=0.004), mitotic index (P=0.019), tumour grade (P=0.048) and FIGO stage (P=0.070). Subanalysis was performed for the patients where the lymph node status was known (n=79). Adding the lymph node status gave as best model for overall survival bcl-2 (P=0.001), lymphovascular permeation (P=0.003) and mitotic index (P=0.044). However, they hardly influenced the association.nnnCONCLUSIONnIn the apoptotic pathway of cervical cancer, bcl-2 is one of most important proteins. It can probably not only mediate cell death but also regulate cell growth. A better understanding of their relations will probably provide the basis for more rational cancer therapies in the future.

Uncovering the Molecular Secrets of Inflammatory Breast Cancer Biology: An Integrated Analysis of Three Distinct Affymetrix Gene Expression Datasets

Background: Inflammatory breast cancer (IBC) is a poorly characterized form of breast cancer. So far, the results of expression profiling in IBC are inconclusive due to various reasons including limited sample size. Here, we present the integration of three Affymetrix expression datasets collected through the World IBC Consortium allowing us to interrogate the molecular profile of IBC using the largest series of IBC samples ever reported. Experimental Design: Affymetrix profiles (HGU133-series) from 137 patients with IBC and 252 patients with non-IBC (nIBC) were analyzed using unsupervised and supervised techniques. Samples were classified according to the molecular subtypes using the PAM50-algorithm. Regression models were used to delineate IBC-specific and molecular subtype-independent changes in gene expression, pathway, and transcription factor activation. Results: Four robust IBC-sample clusters were identified, associated with the different molecular subtypes (P < 0.001), all of which were identified in IBC with a similar prevalence as in nIBC, except for the luminal A subtype (19% vs. 42%; P < 0.001) and the HER2-enriched subtype (22% vs. 9%; P < 0.001). Supervised analysis identified and validated an IBC-specific, molecular subtype-independent 79-gene signature, which held independent prognostic value in a series of 871 nIBCs. Functional analysis revealed attenuated TGF-β signaling in IBC. Conclusion: We show that IBC is transcriptionally heterogeneous and that all molecular subtypes described in nIBC are detectable in IBC, albeit with a different frequency. The molecular profile of IBC, bearing molecular traits of aggressive breast tumor biology, shows attenuation of TGF-β signaling, potentially explaining the metastatic potential of IBC tumor cells in an unexpected manner. Clin Cancer Res; 19(17); 4685–96. ©2013 AACR.

Ultraradical debulking of epithelial ovarian cancer with the ultrasonic surgical aspirator: A prospective randomized trial

OBJECTIVEnOur purpose was to evaluate the effectiveness, benefits, and potential side effects of the use of the cavitational ultrasonic surgical aspirator for cytoreduction of advanced ovarian cancer.nnnSTUDY DESIGNnForty patients with stage IIC to IV ovarian carcinoma were randomized to undergo ultraradical cytoreductive surgery with (group 1, 20 patients) or without (group 2, 20 patients) the use of the CUSA 200 cavitational ultrasonic surgical aspirator (Valleylab, Boulder, Colo). Preoperative and postoperative information and follow-up data were collected prospectively and compared between both groups.nnnRESULTSnThe amount of residual tumor after debulking surgery, the duration of the operation, and the rate of perioperative complications were comparable in both study groups. The amount of perioperative blood loss was significantly lower (1450 ml vs 1650 ml, p=0.02) in group 1. These patients had less morbidity (p<0.05), and could be discharged from the hospital significantly sooner (14 days vs 16 days, p=0.031). CA 125 levels 1 and 2 months after surgery were significantly lower in the group with cavitational ultrasonic surgical aspirator (p<0.01 and p<0.01, respectively), suggesting more successful cytoreduction. However, this is not reflected in a better disease-free or overall survival.nnnCONCLUSIONnCavitational ultrasonic surgical aspirator-assisted cytoreductive surgery of advanced ovarian carcinoma is more effective in eradicating disease, reduces morbidity, and is cost beneficial.

Microarray-based oncogenic pathway profiling in advanced serous papillary ovarian carcinoma.

Introduction The identification of specific targets for treatment of ovarian cancer patients remains a challenge. The objective of this study is the analysis of oncogenic pathways in ovarian cancer and their relation with clinical outcome. Methodology A meta-analysis of 6 gene expression datasets was done for oncogenic pathway activation scores: AKT, β-Catenin, BRCA, E2F1, EGFR, ER, HER2, INFα, INFγ, MYC, p53, p63, PI3K, PR, RAS, SRC, STAT3, TNFα, and TGFβ and VEGF-A. Advanced serous papillary tumours from uniformly treated patients were selected (Nu200a=u200a464) to find differences independent from stage-, histology- and treatment biases. Survival and correlations with documented prognostic signatures (wound healing response signature WHR/genomic grade index GGI/invasiveness gene signature IGS) were analysed. Results The GGI, WHR, IGS score were unexpectedly increased in chemosensitive versus chemoresistant patients. PR and RAS activation score were associated with survival outcome (pu200a=u200a0.002;pu200a=u200a0.004). Increased activations of β-Catenin (pu200a=u200a0.0009), E2F1 (pu200a=u200a0.005), PI3K (pu200a=u200a0.003) and p63 (pu200a=u200a0.05) were associated with more favourable clinical outcome and were consistently correlated with three prognostic gene signatures. Conclusions Oncogenic pathway profiling of advanced serous ovarian tumours revealed that increased β-Catenin, E2F1, p63, PI3K, PR and RAS –pathway activation scores were significantly associated with favourable clinical outcome. WHR, GGI and IGS scores were unexpectedly increased in chemosensitive tumours. Earlier studies have shown that WHR, GGI and IGS are strongly associated with proliferation and that high-proliferative ovarian tumours are more chemosensitive. These findings may indicate opposite confounding of prognostic versus predictive factors when studying biomarkers in epithelial ovarian cancer.

A dynamic clinical pathway for the treatment of patients with early breast cancer is a tool for better cancer care: implementation and prospective analysis between 2002-2010.

BackgroundDue to increasing the complexity of breast cancer treatment it is of paramount importance to develop structured care in order to avoid a chaotic and non-consistent management of patients. Clinical pathways, a result of the adaptation of the documents used in industrial quality management namely the Standard Operating Procedures, can be used to improve efficiency and quality of care. They also aim to re-centre the focus on the patient’s overall journey, rather than the contribution of each specialty or caring function independently.MethodsThe effect of the implementation and prospective systematic evaluation of a clinical care pathway for the management of patients with early breast cancer in a single breast unit is evaluated over a long time interval (between 2002 and 2010). Annual analysis of predefined clinical outcome measures, service indicators, team indicators, process indicators and financial indicators was performed. Pathway quality control meetings were organized at least once a year. Systematic feedback was given to the team members, and if necessary the pathway was adapted according to evidence based literature data and in house pathway related data in order to improve quality.ResultsThe annual number of patients included in the pathway (289 vs. 390, P <0.01), proportion of patients with Tis-T1 tumors (42% vs. 58%, P <0.01), negative lymph nodes (44% vs. 58%, P <0.01) and no metastases at diagnosis (91.5% vs. 95.9%) has risen significantly between 2002 and 2010. Evolution of mandatory quality indicators defined by EUSOMA shows a significant improvement of quality of cancer care. Particularly, the proportion of patients having anti-hormonal therapy (84.8% vs. 97.4%, P = 0.002) and adjuvant chemotherapy according to the guidelines (72% vs. 95.6%, P = 0.028) increased dramatically. Patient satisfaction improved significantly (P <0.05). Progression free 4-year survival was significantly higher for all patients, for T1 tumors only and for T2-T4 tumors only, treated between 2006 to 2008 compared to between 1999 to 2002 and 2003 to 2005 (P = 0.006, P = 0.05, P = 0.06, respectively). Overall 4-year survival of the entire population treated between 2006 and 2008 was significantly better (P = 0.05).ConclusionsAlthough the patient characteristics changed over the years due to better screening, this clinical pathway and regular audit of quality indicators for the treatment of patients with operable breast cancer proved to be important tools to improve the quality of care, patient satisfaction and outcome.

The rationale for mTOR inhibition in epithelial ovarian cancer

The AKT/mTOR signaling pathway is frequently overexpressed in human epithelial ovarian cancer and an attractive target for therapy. In vivo mouse models were confirmative for in vitro findings, where the administration of mTOR inhibitors in ovarian cancer xenografts showed antitumoral as well as antiangiogenic effects. Phase I – II trials are now ongoing with mTOR inhibitors in ovarian cancer patients, some in combination with conventional cytotoxic agents. If further development of mTOR inhibition in ovarian cancer is pursued, studying combinations of mTOR inhibitors with other new targeted therapies would be of interest. mTOR inhibitors in the adjuvant setting could have potential, since, for the moment, there is no standard maintenance therapy in ovarian cancer. A crucial challenge will be to identify strong predictive biomarkers. This review highlights the rationale for the use of mTOR inhibitors in ovarian cancer and summarizes the available preclinical findings.

VEGF-A-independent and angiogenesis-dependent tumour growth in patients with metastatic breast cancer

BackgroundThe mechanisms of tumour progression during anti-VEGF-A treatment are poorly understood.Patients and materialsTwo patients with metastatic breast cancer are described who developed new metastases while receiving anti-VEGF-A treatment. Angiogenic parameters were determined by CD34/Ki67 double staining, Chalkley counts (CC) and endothelial cell proliferation fractions (ECP). RT-PCR Taqman low-density arrays with a gene panel of 94 angiogenesis-related genes were performed on both metastases and compared to 10 unselected primary breast tumours.ResultsBoth lesions showed a high and intermediate CC of, respectively, 7.5±0.62 and 4.8±0.2. Both lesions had elevated ECP values of 14% and 8%. Low-density array screening showed that VEGFR1 mRNA was overexpressed in both samples (z-score=7.85 and 7.81) compared to control samples (out of range [min-max]). Additional analysis confirmed this finding at the protein level by immunohistochemistry.ConclusionThese observations suggest that tumour progression under continuous anti-VEGF-A continues to be angiogenesis dependent. Further exploration is needed to identify the mechanisms of anti-VEGF-A resistance in order to design combination-targeted therapies.

Is there an increased risk for tumor dissemination using ultrasonic surgical aspiration in patients with vulvar carcinoma

The ultrasonic surgical aspirator (USA) is a new surgical instrument that allows precise and selective tissue dissection. Ultrasonic cell destruction is combined with continuous irrigation causing a cloud of fine droplets, which sometimes contains viable tumor cells, hanging above the operative field. We present a patient who developed massive recurrent vulvar carcinoma in the subcutaneous tissue in the proximity of the incisions of the vulva and both groins 3.5 months after a USA-assisted radical vulvectomy and inguinal lymphadenectomy. The atypical pattern of recurrence in the entire operative field suggests that tumor cells might have been spread by the irrigation fluid of the USA. Further investigation is needed to assess the risk of tumor dissemination with USA before the instrument can be used safely in patients with early cancer.