p53 status identifies triple negative breast cancer patients who do not respond to adjuvant chemotherapy

Genomic analysis and protein expression assimilate triple-negative breast cancers (TNBC) with basal-like breast tumors. TNBCs, however, have proved to encompass also tumors with normal-like phenotype and known to have favorable prognosis and to respond to chemotherapy. In a recent paper, we have provided evidence that p53 status is able to subdivide TNBCs into two distinct subgroups with different outcome, and consistent with basal- and normal-like phenotypes. Based on this finding, we explored the contribution of p53 status in predicting the response to adjuvant CMF or CMF followed doxorubicin chemotherapy of a group of TNBC patients. Results indicated that TNBC patients with a p53-positive tumor had a shorter relapse-free and overall survival than patients carrying a p53-negative TNBC, corroborating our hypothesis about the relationship between TNBC phenotype (basal-like versus normal-like) and p53 status as predictor of response to antracycline/CMF-based chemotherapy

Impact of biospecimens handling on biomarker research in breast cancer

<p>Abstract</p> <p>Background</p> <p>Gene expression profiling is moving from the research setting to the practical clinical use.</p> <p>Gene signatures able to correctly identify high risk breast cancer patients as well as to predict response to treatment are currently under intense investigation. While technical issues dealing with RNA preparation, choice of array platforms, statistical analytical tools are taken into account, the tissue collection process is seldom considered.</p> <p>The time elapsed between surgical tissue removal and freezing of samples for biological characterizations is rarely well defined and/or recorded even for recently stored samples, despite the publications of standard operating procedures for biological sample collection for tissue banks.</p> <p>Methods</p> <p>Breast cancer samples from 11 patients were collected immediately after surgical removal and subdivided into aliquots. One was immediately frozen and the others were maintained at room temperature for respectively 2, 6 and 24 hrs. RNA was extracted and gene expression profile was determined using cDNA arrays. Phosphoprotein profiles were studied in parallel.</p> <p>Results</p> <p>Delayed freezing affected the RNA quality only in 3 samples, which were not subjected to gene profiling. In the 8 breast cancer cases with apparently intact RNA also in sample aliquots frozen at delayed times, 461 genes were modulated simply as a function of freezing timing. Some of these genes were included in gene signatures biologically and clinically relevant for breast cancer. Delayed freezing also affected detection of phosphoproteins, whose pattern may be crucial for clinical decision on target-directed drugs.</p> <p>Conclusion</p> <p>Time elapsed between surgery and freezing of samples appears to have a strong impact and should be considered as a mandatory variable to control for clinical implications of inadequate tissue handling.</p

Circulating tumor DNA and disease recurrence in early stage breast cancer: From a case-control study to a prospective longitudinal trial

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the curious phenomenon of dual positive circulating cells longtime overlooked tumor cells

Abstract The presence in the blood of patients with solid tumors of circulating cells expressing both epithelial and leukocyte markers (dual-positive cells, DPcells), has often been reported, though it has never been investigated in detail. A recent study suggested that DPcells are hybrid cells derived from the fusion of tumor cells with macrophages. Such fusion hybrids acquire macrophage-associated features endowing them with accelerated growth, increased motility, enhanced invasion activity and thus, a higher efficiency in metastasis formation. However, no direct evidence proving the tumor origin of circulating DPcells was provided in patients. Here we contribute a review of literature data on DPcells and on the hybrid theory with the aim of putting the current evidence both in a biological and clinical perspective and to generate new hypotheses on the mechanisms underlying tumor progression. To add further biological and clinical context to our literature review, we also report some preliminary data from our laboratory on the identification of DPcells in several solid tumors and confirmation of their malignant genotype, thus classifying them as DP-CTCs

miR-21: an oncomir on strike in prostate cancer

<p>Abstract</p> <p>Background</p> <p>Aberrant expression of microRNAs, small non-coding RNA molecules that post-transcriptionally repress gene expression, seems to be causatively linked to the pathogenesis of cancer. In this context, miR-21 was found to be overexpressed in different human cancers (e.g. glioblastoma, breast cancer). In addition, it is thought to be endowed with oncogenic properties due to its ability to negatively modulate the expression of tumor-suppressor genes (e.g. <it>PTEN</it>) and to cause the reversion of malignant phenotype when knocked- down in several tumor models. On the basis of these findings, miR-21 has been proposed as a widely exploitable cancer-related target. However, scanty information is available concerning the relevance of miR-21 for prostate cancer. In the present study, we investigated the role of miR-21 and its potential as a therapeutic target in two prostate cancer cell lines, characterized by different miR-21 expression levels and <it>PTEN </it>gene status.</p> <p>Results</p> <p>We provide evidence that miR-21 knockdown in prostate cancer cells is not sufficient <it>per se </it>i) to affect the proliferative and invasive potential or the chemo- and radiosensitivity profiles or ii) to modulate the expression of the tumor-suppressors PTEN and Pdcd4, which in other tumor types were found to be regulated by miR-21. We also show that miR-21 is not differently expressed in carcinomas and matched normal tissues obtained from 36 untreated prostate cancer patients subjected to radical prostatectomy.</p> <p>Conclusions</p> <p>Overall, our data suggest that miR-21 is not a central player in the onset of prostate cancer and that its single hitting is not a valuable therapeutic strategy in the disease. This supports the notion that the oncogenic properties of miR-21 could be cell and tissue dependent and that the potential role of a given miRNA as a therapeutic target should be contextualized with respect to the disease.</p

Identification, validation and clinical implementation of cancer biomarkers: Translational strategies of the EORTC PathoBiology Group

AbstractThe increasing demand for personalized cancer therapy requires a strong, intense, and continuous collaboration between pre-clinical and clinical investigators. As a part of the EORTC Translational Research Divison, the EORTC PathoBiology Group (EORTC PBG), focuses on discovery and validation of cancer biomarkers, providing both scientific evidence as well as quality assurance. The clinically relevant target-identification and validation studies carried out in the last decades within the EORTC PBG represent a paradigm for EORTC studies in which laboratory investigations on human biologic material are used to support the development of drugs directed to defined target molecules. The experience acquired within the EORTC PBG with respect to standardization of cancer biomarker test kits and reagents, quality assessment/assurance of cancer biomarker determinations, development of standard operating procedures for assessment of these markers as well as instruction of methodologies and teaching of ethical issues represent a valuable contribution of the EORTC PBG to the onco-translational strategies of the EORTC