When a collective outcome triggers a rare individual event: a mode of metastatic process in a cell population

A model of early metastatic process is based on the role of the protein PAI-1, which at high enough extracellular concentration promotes the transition of cancer cells to a state prone to migration. This transition is described at the single cell level as a bi-stable switch associated with a subcritical bifurcation. In a multilevel reaction-diffusion scenario, the microenvironment of the tumor is modified by the proliferating cell population so as to push the concentration of PAI-1 above the bifurcation threshold. The formulation in terms of partial differential equations fails to capture spatio-temporal heterogeneity. Cellular-automata and agent-based simulations of cell populations support the hypothesis that a randomly localized accumulation of PAI-1 can arise and trigger the escape of a few isolated cells. Far away from the primary tumor, these cells experience a reverse transition back to a proliferative state and could generate a secondary tumor. The proposed role of PAI-1 in controlling this metastatic cycle is candidate to explain its role in the progression of cancer

A randomized trial comparing adjuvant chemotherapy with gemcitabine plus cisplatin with docetaxel plus cisplatin in patients with completely resected non-small-cell lung cancer with quality of life as the primary objective

International audienceOBJECTIVES: Adjuvant chemotherapy with vinorelbine plus cisplatin (VC) improves survival in resected non-small-cell lung cancer (NSCLC), but has negative impact on quality of life (QoL). In advanced NSCLC, gemcitabine plus cisplatin (GC) and docetaxel plus cisplatin (DC) exhibit comparable efficacy, with possibly superior QoL compared to VC. This trial investigated these regimens in the adjuvant setting. METHODS: Patients with Stage IB to III NSCLC were eligible following standardized surgery. Overall, 136 patients were included, with 67 and 69 assigned to the GC and DC arms, respectively. Cisplatin (75 mg/m(2), Day [D] 1) plus gemcitabine (1250 mg/m(2), D1 and D8) or docetaxel (75 mg/m(2) D1) were administered for three cycles. Primary end-point was QoL (EORTC QLQ-C30), with the study designed to detect a 10-point difference between arms. Overall survival, safety and cost were secondary end-points. RESULTS: No between-group imbalance was observed in terms of patient characteristics. At inclusion, global health status (GHS) scores (/100) were 63.5 and 62.7 in GC and DC, respectively (P = 0.8), improving to 64.5 and 65.4 after 3 months (P = 0.8). No significant difference in functional or symptoms scores was observed between the arms except for alopecia. Grade 3/4 haematological and non-haematological toxicities were found in 33.8 and 21.7% (P = 0.11), and 33.8 and 26.1% (P = 0.33) of patients, in GC and DC, respectively. At 2 years, 92.9 and 89.8% of patients remained alive in GC and DC, respectively (P = 0.88). CONCLUSIONS: DC and GC adjuvant chemotherapies for completely resected NSCLC were well tolerated and appear free of major QoL effects, and are therefore representing candidates for comparison with the standard VC regimen

Genome wide SNP comparative analysis between EGFR and KRAS mutated NSCLC and characterization of two models of oncogenic cooperation in non-small cell lung carcinoma

<p>Abstract</p> <p>Background</p> <p>Lung cancer with EGFR mutation was shown to be a specific clinical entity. In order to better understand the biology behind this disease we used a genome wide characterization of loss of heterozygosity and amplification by Single Nucleotide Polymorphism (SNP) Array analysis to point out chromosome segments linked to <it>EGFR </it>mutations. To do so, we compared genetic profiles between <it>EGFR </it>mutated adenocarcinomas (ADC) and <it>KRAS </it>mutated ADC from 24 women with localized lung cancer.</p> <p>Results</p> <p>Patterns of alterations were different between <it>EGFR </it>and <it>KRAS </it>mutated tumors and specific chromosomes alterations were linked to the <it>EGFR </it>mutated group. Indeed chromosome regions 14q21.3 (p = 0.027), 7p21.3-p21.2 (p = 0.032), 7p21.3 (p = 0.042) and 7p21.2-7p15.3 (p = 0.043) were found significantly amplified in EGFR mutated tumors. Within those regions 3 genes are of special interest <it>ITGB8</it>, <it>HDAC9 </it>and <it>TWIST1</it>. Moreover, homozygous deletions at <it>CDKN2A </it>and LOH at <it>RB1 </it>were identified in <it>EGFR </it>mutated tumors. We therefore tested the existence of a link between EGFR mutation, CDKN2A homozygous deletion and cyclin amplification in a larger series of tumors. Indeed, in a series of non-small-cell lung carcinoma (n = 98) we showed that homozygous deletions at <it>CDKN2A </it>were linked to <it>EGFR </it>mutations and absence of smoking whereas cyclin amplifications (<it>CCNE1 </it>and <it>CCND1</it>) were associated to <it>TP53 </it>mutations and smoking habit.</p> <p>Conclusion</p> <p>All together, our results show that genome wide patterns of alteration differ between <it>EGFR </it>and <it>KRAS </it>mutated lung ADC, describe two models of oncogenic cooperation involving either <it>EGFR </it>mutation and <it>CDKN2A </it>deletion or cyclin amplification and <it>TP53 </it>inactivating mutations and identified new chromosome regions at 7p and 14q associated to EGFR mutations in lung cancer.</p

PAI-1 and functional blockade of SNAI1 in breast cancer cell migration

12 pages, 5 figures.-- PMID: 19055748 [PubMed].-- et al.[Introduction]: Snail, a family of transcriptional repressors implicated in cell movement, has been correlated with tumour invasion. The Plasminogen Activation (PA) system, including urokinase plasminogen activator (uPA), its receptor and its inhibitor, plasminogen activator inhibitor type 1(PAI-1), also plays a key role in cancer invasion and metastasis, either through proteolytic degradation or by non-proteolytic modulation of cell adhesion and migration. Thus, Snail and the PA system are both over-expressed in cancer and influence this process. In this study we aimed to determine if the activity of SNAI1 (a member of the Snail family) is correlated with expression of the PA system components and how this correlation can influence tumoural cell migration.[Methods]: We compared the invasive breast cancer cell-line MDA-MB-231 expressing SNAI1 (MDA-mock) with its derived clone expressing a dominant-negative form of SNAI1 (SNAI1-DN). Expression of PA system mRNAs was analysed by cDNA microarrays and real-time quantitative RT-PCR. Wound healing assays were used to determine cell migration. PAI-1 distribution was assessed by immunostaining.[Results]: We demonstrated by both cDNA microarrays and realtime quantitative RT-PCR that the functional blockade of SNAI1 induces a significant decrease of PAI-1 and uPA transcripts. After performing an in vitro wound-healing assay, we observed that SNAI1-DN cells migrate more slowly than MDA-mock cells and in a more collective manner. The blockade of SNAI1 activity resulted in the redistribution of PAI-1 in SNAI1-DN cells decorating large lamellipodia, which are commonly found structures in these cells.[Conclusions]: In the absence of functional SNAI1, the expression of PAI-1 transcripts is decreased, although the protein is redistributed at the leading edge of migrating cells in a manner comparable with that seen in normal epithelial cells.This work was supported by the CNRS ACI Program "Complexité du vivant" (grant # 050009DR11) and by the Evry Genopole grant "Aide à l'acquisition d'équipement semi-lourd" 2007 and 2008.Peer reviewe

Peripheral primitive neuroectodermal tumor of the cauda equina in an elderly patient. Case report.

International audiencePrimitive neuroectodermal tumors (PNETs) are aggressive neoplasms composed predominantly of undifferentiated cells that show evidence of neural differentiation. Although their classification remains disputed, PNETs are recognized as primary tumors in both the central and peripheral nervous systems. These rare tumors usually occur in children or young adults and are typically metastatic to the spinal cord. The authors report the case of a 70-year-old man with no significant medical history, in whom a peripheral PNET was demonstrated that, based on clinical and imaging findings, manifested as a nonspecific intrathecal tumoral process arising from the cauda equina. Although this lesion is rare in the elderly, the authors' case illustrates the importance of making this diagnosis as early as possible so that a treatment plan may be devised. The use of chemotherapy in association with radiotherapy in relation to the resection of the tumor should be reconsidered

Cancer bronchique non à petites cellules

The precocity of the diagnosis of non small lung cancers (NSCLC) is crucial. Only 30% of these tumours are operable at the time of diagnosis, and so, lung cancer .represents the first cause of mortality in France. Symptoms are late and quiet aspecific. A normal chest radiography does not eliminate the diagnosis, and assessment must be continued according to clinical suspicions. Recent advances in the field of imaging, as positron emission tomography have considerably modified therapeutic decision. Initial assessment establishes the TNM staging which defines therapeutic strategies. Final decision is retained after a multidisciplinary discussion integrating patient&apos;s comorbidities and personal history. Treatment of lung cancers has largely been improved by the development of conformational radiotherapy, peri-operative chemotherapy, interventional endoscopy and biologic targeted therapies

When a collective outcome triggers a rare individual event: a mode of metastatic process in a cell population

A model of early metastatic process is based on the role of the protein PAI-1, which at high enough extracellular concentration promotes the transition of cancer cells to a state prone to migration. This transition is described at the single cell level as a bi-stable switch associated with a subcritical bifurcation. In a multilevel reaction-diffusion scenario, the microenvironment of the tumor is modified by the proliferating cell population so as to push the concentration of PAI-1 above the bifurcation threshold. The formulation in terms of partial differential equations fails to capture spatio-temporal heterogeneity. Cellular-automata and agent-based simulations of cell populations support the hypothesis that a randomly localized accumulation of PAI-1 can arise and trigger the escape of a few isolated cells. Far away from the primary tumor, these cells experience a reverse transition back to a proliferative state and could generate a secondary tumor. The proposed role of PAI-1 in controlling this metastatic cycle is candidate to explain its role in the progression of cancer

Epidermal growth factor receptor mutation in lung cancer are linked to bronchioloalveolar differentiation

International audienceIn lung cancer, an association was made between drastic clinical response to epidermal growth factor receptor (EGFR) inhibitors and the presence of somatic mutations within the tyrosine kinase domain of the EGFR. In some cases, patients with partial response or disease stabilization do not always have EGFR-mutated tumors. To go further in the characterization of the EGF pathway, we screened EGFR, ERBB2, ERBB3, KRAS, BRAF, and PIK3CA for mutations in 2 groups of White patients with nonsmall cell lung cancer (45 cancers from women and 46 cancers from men). Associations between TP53 mutations, clinicopathologic parameters, and EGF pathway molecular alterations were analyzed. All mutations were exclusive and essentially found in EGFR and KRAS. We demonstrated that EGFR mutations were linked to female sex, absence of smoking, late age at diagnosis, and adenocarcinoma (ADC) with bronchioloalveolar (BAC) features. Moreover, in invasive ADC with BAC component, microdissection assays showed that mutations were retrieved in both tumor subtypes suggesting that EGFR mutations appear early in lung carcinogenesis. On the contrary, KRAS mutations correlated with smoking, younger age at diagnosis, and ADC subtype regardless of BAC differentiation. These results suggest the existence of distinct carcinogenesis pathways both leading to disruption of EGF regulation and targeted either by tobacco carcinogens or by unidentified toxic. The identification of BAC features in ADC helps clustering patients that are more likely to fit the EGFR-mutated group

What is the place of clinical variables in advanced non-small cell lung cancer (NSCLC) patients treated with chemotherapy ?

International audienceBackground: Chemotherapy (CT) has shown its effectiveness in symptom control and quality of life improvement in advanced NSCLC patients. The therapeutic strategy and some clinical variables could have a major impact on outcome. Methods: Our retrospective analysis evaluated the impact on overall survival (OS) of the clinical benefit (CB), ECOG performance status (PS) and toxicity, function of treatment. CB was defined as disease-related symptoms improvement according to hospitalization report. Only grade III-IV CTC-NCI version 2 toxicities have been considered. OS was calculated between start of CT and death or last follow-up. Multivariate Cox regression analysis including CB, PS, toxicity and age, stratified by AJCC initial stage was used. Results: Data of 68 consecutive stage IIIB-IV patients treated in a single French centre were analyzed. Chemotherapy was platinum-salt based in 88, 45 and 25% of pts for the first, second and third-line, respectively. Median age was 61 years, 37% were women. More than half (66%) were metastatic and 14% were previously irradiated. Median survival was 14 months (95% CI, 6.1-21.8), 53 % of patients are dead. The risk of death PS-related was multiplied by 2.3, 2.4 and 5.3 for the first, second and third-line of CT, respectively. PS and CB were initially associated with OS (first and second-line CT), but after the third-line of CT only PS was significantly related with OS. The risk of death reduction induced by a CB was 59, 82 and 29%, respectively. Less toxicities during CT were associated with a better OS (an unsignificant 20- 30% risk of death reduction), independently of the chronology of CT. Older pts >70 years have a higher risk of death (HR=1.87), independently of the CB and treatment-related toxicities in the multivariate analysis (P=0.18), sex-adjusted. Conclusions: No matter how many lines of CT are used for a specified patient, the ECOG PS was a patient-related variable with a dominant impact on the outcome. CT must be less toxic in order to achieve a CB and ameliorate the PS