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author:("leconte, A")
1.  Molecular heterogeneity and prognostic implications of synchronous advanced colorectal neoplasia 
British Journal of Cancer  2014;110(5):1228-1235.
It is uncertain whether synchronous colorectal cancers (S-CRCs) preferentially develop through widespread DNA methylation and whether they have a prognosis worse than solitary CRC. As tumours with microsatellite instability (MSI) may confound the effect of S-CRC methylation on outcome, we addressed this issue in a series of CRC characterised by BRAF and MS status.
Demographics, clinicopathological records and disease-specific survival (DSS) were assessed in 881 consecutively resected CRC undergoing complete colonoscopy. All tumours were typed for BRAFc.1799T>A mutation and MS status, followed by search of germ-line mutation in patients with MSI CRC.
Synchronous colorectal cancers (50/881, 5.7%) were associated with stage IV microsatellite-stable (MSS) CRC (19/205, 9.3%, P=0.001) and with HNPCC (9/32, 28%, P<0.001). BRAF mutation (60/881, 6.8%) was associated with sporadic MSI CRC (37/62, 60%, P<0.001) but not with S-CRC (3/50, 6.0%, P=0.96). Synchronous colorectal cancer (HR 1.82; 95% CI 1.15–2.87; P=0.01), synchronous advanced adenoma (HR 1.81; 95% CI 1.27–2.58; P=0.001), and BRAFc.1799T>A mutation (HR 2.16; 95% CI 1.25–3.73; P=0.01) were stage-independent predictors of death from MSS CRC. Disease-specific survival of MSI CRC patients was not affected by S-CRC (HR 0.74; 95% CI 0.09–5.75; P=0.77).
Microsatellite-stable CRCs have a worse prognosis if S-CRC or synchronous advanced adenoma are diagnosed. The occurrence and the enhanced aggressiveness of synchronous MSS advanced neoplasia are not associated with BRAF mutation.
PMCID: PMC3950856  PMID: 24434431
synchronous colorectal cancer; advanced adenoma; microsatellite instability; BRAF mutation; prognosis
2.  Early expression of the fractalkine receptor CX3CR1 in pancreatic carcinogenesis 
British Journal of Cancer  2013;109(9):2424-2433.
In pancreatic ductal adenocarcinoma (PDAC), fractalkine receptor CX3CR1 contributes to perineural invasion (PNI). We investigated whether CX3CR1 expression occurs early in PDAC and correlates with tumour features other than PNI.
We studied CX3CR1 and CX3CL1 expression by immunohistochemistry in 104 human PDAC and coexisting Pancreatic Intraepithelial Neoplasia (PanIN), and in PdxCre/LSL-KrasG12D mouse model of PDAC. CX3CR1 expression in vitro was studied by a spheroid model, and in vivo by syngenic mouse graft of tumour cells.
In total, 56 (53.9%) PDAC expressed CX3CR1, 70 (67.3%) CX3CL1, and 45 (43.3%) both. CX3CR1 expression was independently associated with tumour glandular differentiation (P=0.005) and PNI (P=0.01). Pancreatic Intraepithelial Neoplasias were more frequently CX3CR1+ (80.3%, P<0.001) and CX3CL1+ (86.8%, P=0.002) than matched cancers. The survival of PDAC patients was better in those with CX3CR1+ tumour (P=0.05). Mouse PanINs were also CX3CR1+ and -CL1+. In vitro, cytokines significantly increased CX3CL1 but not CX3CR1 expression. Differently, CX3CR1 was upregulated in tumour spheroids, and in vivo only in well-differentiated tumours.
Tumour differentiation, rather than inflammatory signalling, modulates CX3CR1 expression in PanINs and PDAC. CX3CR1 expression pattern suggests its early involvement in PDAC progression, outlining a potential target for interfering with the PanIN transition to invasive cancer.
PMCID: PMC3817321  PMID: 24084767
pancreatic cancer; pancreatic intraepithelial neoplasia (PanIN); chemokines and chemokine receptors; tumour differentiation
3.  Pax7 Lineage Contributions to the Mammalian Neural Crest 
PLoS ONE  2012;7(7):e41089.
Neural crest cells are vertebrate-specific multipotent cells that contribute to a variety of tissues including the peripheral nervous system, melanocytes, and craniofacial bones and cartilage. Abnormal development of the neural crest is associated with several human maladies including cleft/lip palate, aggressive cancers such as melanoma and neuroblastoma, and rare syndromes, like Waardenburg syndrome, a complex disorder involving hearing loss and pigment defects. We previously identified the transcription factor Pax7 as an early marker, and required component for neural crest development in chick embryos. In mammals, Pax7 is also thought to play a role in neural crest development, yet the precise contribution of Pax7 progenitors to the neural crest lineage has not been determined.
Methodology/Principal Findings
Here we use Cre/loxP technology in double transgenic mice to fate map the Pax7 lineage in neural crest derivates. We find that Pax7 descendants contribute to multiple tissues including the cranial, cardiac and trunk neural crest, which in the cranial cartilage form a distinct regional pattern. The Pax7 lineage, like the Pax3 lineage, is additionally detected in some non-neural crest tissues, including a subset of the epithelial cells in specific organs.
These results demonstrate a previously unappreciated widespread distribution of Pax7 descendants within and beyond the neural crest. They shed light regarding the regionally distinct phenotypes observed in Pax3 and Pax7 mutants, and provide a unique perspective into the potential roles of Pax7 during disease and development.
PMCID: PMC3407174  PMID: 22848431
4.  Prognostic Value of Colorectal Cancer Biomarkers 
Cancers  2011;3(2):2080-2105.
Despite the large amount of data in cancer biology and many studies into the likely survival of colorectal cancer (CRC) patients, knowledge regarding the issue of CRC prognostic biomarkers remains poor. The Tumor-Node-Metastasis (TNM) staging system continues to be the most powerful and reliable predictor of the clinical outcome of CRC patients. The exponential increase of knowledge in the field of molecular genetics has lead to the identification of specific alterations involved in the malignant progression. Many of these genetic alterations were proposed as biomarkers which could be used in clinical practice to estimate CRC prognosis. Recently there has been an explosive increase in the number of putative biomarkers able to predict the response to specific adjuvant treatment. In this review we explore and summarize data concerning prognostic and predictive biomarkers and we attempt to shed light on recent research that could lead to the emergence of new biomarkers in CRC.
PMCID: PMC3757405  PMID: 24212797
colorectal cancer; prognostic biomarkers; predictive biomarkers
5.  Embryonic Pax7-expressing progenitors contribute multiple cell types to the postnatal olfactory epithelium 
Prolonged neurogenesis driven by stem/progenitor cells is a hallmark of the olfactory epithelium (OE), beginning at the placodal stages in the embryo and continuing throughout adult life. Despite the progress made to identify and study the regulation of adult OE progenitors, our knowledge of embryonic OE precursors and their cellular contributions to the adult OE has been stalled by the lack of markers able to distinguish individual candidate progenitors. Here we identify embryonic OE Pax7+ progenitors, detected at E11.5 in the olfactory pit with an antigen profile and location previously assigned to presumptive OE stem cells. Using Cre-loxP technology (Pax7-cre/ROSA YFP mice) we expose a wide range of derivatives, including CNS and olfactory neurons, non-neuronal cells and olfactory ensheathing glia, all made from embryonic Pax7 + cells. Importantly, the expression of Pax7 in the embryonic OE is downregulated from E15.5, such that after birth, no Pax7+ cells are found in the OE, and thus the progenitor population here identified is restricted to embryonic stages. Our results provide the first evidence for a population of Pax7-expressing embryonic progenitors that contribute to multiple OE lineages and demonstrate novel insights into the unique spatiotemporal patterning of the postnatal OE.
PMCID: PMC2920205  PMID: 20631180
Pax7; olfactory; progenitor; embryonic; neuroglial; genetic fate mapping
6.  The let-7 microRNA target gene, Mlin41/Trim71 is required for mouse embryonic survival and neural tube closure 
Cell cycle (Georgetown, Tex.)  2008;7(24):3935-3942.
In the nematode Caenorhabditis elegans, the let-7 microRNA (miRNA) controls the timing of key developmental events and terminal differentiation in part by directly regulating lin-41. C. elegans lin-41 mutants display precocious cell cycle exit and terminal differentiation of epidermal skin cells. lin-41 orthologues are found in more complex organisms including both mice and humans, but their roles are not known. We generated Mlin41 mouse mutants to ascertain a functional role for Mlin41. Strong loss of function Mlin41 gene-trap mutants demonstrated a striking neural tube closure defect during development, and embryonic lethality. Like C. elegans lin-41, Mlin41 also appears to be regulated by the let-7 and mir-125 miRNAs. Since Mlin41 is required for neural tube closure and survival it points to human lin-41 (HLIN41/TRIM71) as a potential human development and disease gene.
PMCID: PMC2895810  PMID: 19098426
microRNA; let-7; mir-125; mlin41; lin-41; mouse; knock-out; development; cell cycle
7.  A comparison of the efficacy of darifenacin alone vs. darifenacin plus a Behavioural Modification Programme upon the symptoms of overactive bladder 
This study assessed the benefit of adding behavioural modification to darifenacin treatment for overactive bladder (OAB).
Materials and methods
The ABLE trial was a randomised, open-label, parallel-group, multicentre study of 12 weeks of darifenacin treatment [with voluntary up-titration from 7.5 mg once daily (qd) to 15 mg qd at week 2] alone or in combination with a Behavioural Modification Programme (BMP) for men and women with dry or wet OAB. Efficacy was assessed as the change in the number (per day) of micturitions (primary variable), urge urinary incontinence (UUI) episodes, urgency episodes, pads used and nocturnal voids. Health-related quality of life (HRQoL) was also evaluated. Tolerability and safety assessments included adverse events and the number of discontinuations.
Of 592 patients screened, 395 were randomised, 190 to darifenacin alone and 205 to darifenacin + BMP. At baseline, the majority of subjects were dry (mean 2.8 and three UUI episodes per day in the darifenacin and darifenacin + BMP groups respectively). At study end, darifenacin alone and darifenacin + BMP both produced significant reductions from baseline in median numbers of micturitions, UUI episodes, urgency episodes and nocturnal voids (all p < 0.05), but not in the number of pads used. HRQoL also improved. There were no significant differences between treatment groups in efficacy or HRQoL variables.
Darifenacin treatment provides a degree of normalisation of micturition variables and improvement in HRQoL that cannot be further enhanced by behavioural therapy of the type used in this study. Whether behavioural modification would add benefit over darifenacin treatment in patients with more pronounced incontinence problems remains to be determined.
PMCID: PMC2325270  PMID: 18324952
8.  Design strategies to improve patient motivation during robot-aided rehabilitation 
Motivation is an important factor in rehabilitation and frequently used as a determinant of rehabilitation outcome. Several factors can influence patient motivation and so improve exercise adherence. This paper presents the design of two robot devices for use in the rehabilitation of upper limb movements, that can motivate patients during the execution of the assigned motor tasks by enhancing the gaming aspects of rehabilitation. In addition, a regular review of the obtained performance can reinforce in patients' minds the importance of exercising and encourage them to continue, so improving their motivation and consequently adherence to the program. In view of this, we also developed an evaluation metric that could characterize the rate of improvement and quantify the changes in the obtained performance.
Two groups (G1, n = 8 and G2, n = 12) of patients with chronic stroke were enrolled in a 3-week rehabilitation program including standard physical therapy (45 min. daily) plus treatment by means of robot devices (40 min., twice daily) respectively for wrist (G1) and elbow-shoulder movements (G2). Both groups were evaluated by means of standard clinical assessment scales and the new robot measured evaluation metric. Patients' motivation was assessed in 9/12 G2 patients by means of the Intrinsic Motivation Inventory (IMI) questionnaire.
Both groups reduced their motor deficit and showed a significant improvement in clinical scales and the robot measured parameters. The IMI assessed in G2 patients showed high scores for interest, usefulness and importance subscales and low values for tension and pain subscales.
Thanks to the design features of the two robot devices the therapist could easily adapt training to the individual by selecting different difficulty levels of the motor task tailored to each patient's disability. The gaming aspects incorporated in the two rehabilitation robots helped maintain patients' interest high during execution of the assigned tasks by providing feedback on performance. The evaluation metric gave a precise measure of patients' performance and thus provides a tool to help therapists promote patient motivation and hence adherence to the training program.
PMCID: PMC1805445  PMID: 17309790

Results 1-8 (8)