Mehdi Bourouba

Nasopharyngeal carcinoma (NPC) is thought to arise because of chronic inflammation. The correlation between nitric oxide (NO) production, a biomarker of inflammation and NPC development remains unexplored. To investigate this question, we performed a profile analysis on plasma collected from untreated, treated, remissive, cured and relapsing patients. Nitrites were measured to assess NO activity. We observed that increased nitrites concentrations in untreated and relapsing patients associated with tumor development. Moreover, nitrites levels were similar in remissive, cured and healthy individuals. Altogether, our results suggest that NO might be an interesting blood biomarker to monitor tumor growth in NPC patients.

Predicting tumor recurrence and death in patients with nasopharyngeal carcinoma (NPC) remains to date challenging. We here analyzed the plasmatic secretomes of NPC untreated and relapsing patients, and explored possible correlations with the clinical and pathological features and survival characteristics of the corresponding patient cohorts, with the aim of identifying novel prognostic biomarkers. This study included 27 controls, 45 untreated NPC and 11 relapsed patients. A set of 14 plasma cytokines were analyzed using Millipore multiplex assay. Nitrites were assessed by Griess method. A comparative analysis of each groups' secretome showed upregulation of IL-8, IL-12p70, IL-10 and IP-10 in untreated patients, and of IL-6, IL-10, MCP-1 and IP-10 in relapsing patients. Nitrites significantly correlated with IL-8 during relapse. Secretomes' network analyses revealed prevalence of high correlations between IL8/IL-17A and IFN-γ/IL12p70 in the control group, between TNF-α/IL-8/IL-6, TNF-α/VEGF/IFN-γ and IL-10/MCP-1 in the untreated group, and between IL-8/IL-6/IL-10, TNF-α/IL-8/IL-6, IL12-p70/VEGF/IL-10/IFN-γ, IL-6/IL-10/IFN-γ and IL-8/IP-10 in the relapse group. IL-12p70, IP-10 and MCP-1 levels respectively associated with gender, age and node metastasis respectively. Recurrence-free survival (RFS) analysis showed that patients presenting High IL-8/Low NO immunological scores presented a combined 80% probability of relapse/death after 53 months (combined log-rank test p = 0.0034; individual p = 0.012 and p = 0.016). Multivariate Cox hazard regression analysis revealed that IL-8 (HR = 7.451; 95% CI [2.398-23.152]; p = 0.001) and treatment type (HR = 0.232; 95% CI 0.072-0.749; p = 0.015) were independent prognostic factors. C&RT decision tree analysis showed that High IL-8/Low NO immunological scores predicted treatment failure in 50% cases starting the 36th month of follow-up (AUC = 1) for all of the studied cases and in 57% cases for patients receiving chemotherapy alone (AUC = 1). Altogether, our results showed that NPC development is accompanied with cytokines deregulation to form specific interaction networks at time of diagnosis and relapse, and demonstrate that High IL-8/Low NO signature may constitute a predictor of poor prognosis which may be useful to improve risk stratification and therapy failure management.

Despite the increasing incidence of laryngeal squamous cell carcinoma (LSCC) in Algeria, scarce information is available on the importance of the preventable etiological factors which may drive the disease. Remarkably, a significant number of cases occur in nonsmoker and nondrinker patients; hence, suggesting that alternative risk factors, like Human papillomavirus (HPV), might be etiologically involved. To gain more insight on the risk factors associated with the disease in the country, we evaluated the etiological fraction of HPV in comparison to tobacco and alcohol intake in LSCC patients. To evaluate the etiopathologic fraction (EF) for HPV compared to history of tobacco and alcohol in LSCC, HPV DNA presence in 46 invasive and 3 non-invasive formalin-fixed paraffin-embedded laryngeal tumors was screened using the SPF10-DEIA-LiPA25 Assay. Demographic data and information related to exposure to the risk factors were gathered through interviewer-assisted questionnaires. We observed...

We previously showed that in patients, nitric oxide synthase activity (NOS2) promoted nasopharyngeal tumor growth (NPC). Tumor necrosis factor (TNF α ) is a pro-inflammatory cytokine which engages nitric oxide (NO ∗ ) in several carcinogenic processes. In NPC patients, TNF α synthesis associates with poor survival. Here, we aimed at determining whether TNF α signaling inhibition could alter NOS2 dependent NPC growth in vitro. For this purpose, TNF α influence on nitrite production and tumor cell proliferation were analyzed. We observed that monocytes/macrophages (Mo/Ma) and primary tumor biopsies, isolated from patients, synthesized significant amounts of nitrites. Endogenous TNF α neutralization with an anti-TNF α monoclonal antibody (mAb) successfully inhibited nitrites synthesis by Mo/Ma and tumor explants. Recombinant TNF α (rTNF α ) enhanced nitrites synthesis and C666-1 NPC cells proliferation. Treatment with the NOS2 selective inhibitor (1400 W) and an anti-TNF α mAb potently inhibited rTNF α induced C666-1 proliferation and nitrites synthesis. Strikingly, patients tumors explants treated with the anti-TNF α mAb displayed reduced proliferation as indicated by Ki67 index. Altogether, our results define Mo/Ma and the primary tumor as major sources of circulating NO ∗ in NPC patients and support the idea that antibody dependent inhibition of the TNF α /NOS2 inflammatory pathway may alter nasopharyngeal carcinoma tumor growth.

In North Africa, nasopharyngeal carcinoma (NPC) is characterized by a bimodal distribution involving a juvenile (≤  30 years old) and an elder population (> 30 years old). The Epstein Barr virus oncogene LMP1, the anti-apoptotic Bcl-2 protein and the tumor suppressor p53 have recently emerged as biomarkers of the disease. EGFR/ErbB1 expression is detected in the majority of NPC tumors with advanced disease. To obtain greater insight into the potential oncogenic mechanisms specific to these two NPC populations, we examined the correlation between EGFR expression and patient age, and determined the molecular profiles of its associations with the biomarkers of NPC. We performed an immunohistochemical analysis of the latter molecules in NPC specimens from eleven Algerian patients (six patients  ≤  30 years of age and five patients > 30 years of age) using the LSAB method. Evaluation of the biopsies, based on the intensity of staining and the percentage of positive cells, showed th...

Nasopharyngeal carcinoma (NPC) is thought to arise because of chronic inflammation. The correlation between nitric oxide (NO) production, a biomarker of inflammation and NPC development remains unexplored. To investigate this question, we performed a profile analysis on plasma collected from untreated, treated, remissive, cured and relapsing patients. Nitrites were measured to assess NO activity. We observed that increased nitrites concentrations in untreated and relapsing patients associated with tumor development. Moreover, nitrites levels were similar in remissive, cured and healthy individuals. Altogether, our results suggest that NO might be an interesting blood biomarker to monitor tumor growth in NPC patients.

Laryngeal squamous cell carcinoma (LSCC) is an aggressive malignancy which lacks early predictors of prognosis. Here, we hypothesized that expression and prognostic characterization of the critical mediators of epithelial to mesenchymal transition (EMT) may provide key information in this regard. Linear regression and multiple correspondence analyses were performed on immunohistochemical data obtained from 20 invasive tumors. Principal component and unsupervised hierarchical clustering were used to analyze the dataset patterns associating with LSCC metastatic profile. Survival and death risk assessments were performed using Kaplan–Meier and hazard ratio tests. Data mining analysis using CHAID decision tree and logistic regression analysis was applied to define the predictive value of the risk factors of tumor aggressiveness. Our analyses showed, that in invasive LSCC tumors, cells associating with a mesenchymal profile were likely to exhibit enhanced NOS2, TGF-β, and IL-17A expressi...

C4.4A is a member of the Ly6 family, with low homology to uPAR. It has been detected mainly on metastasizing carcinoma cells and proposed to be involved in wound healing. So far, C4.4A has been observed as an orphan receptor, and its functional activity has not been explored. Using recombinant rat C4.4A (rrC4.4A) made in a eukaryotic expression system, we demonstrate by immunohistology that C4.4A ligands are strongly expressed in tissues adjacent to squamous epithelia of, e.g., tongue and esophagus, the expression pattern partly overlapping with laminin (LN) and complementing the C4.4A expression that is found predominantly on the basal layers of squamous epithelium. ELISA screening of several components of the extracellular matrix revealed selective binding of rrC4.4A to LN1 and LN5 and that transfection of the BSp73AS tumor line with C4.4A cDNA (BSp73AS‐1B1) promoted LN1 and LN5 binding. Binding of BSp73AS‐1B1 to LN5 and, less markedly, LN1 induced spreading, lamellipodia formation and migration. C4.4A also associates with galectin‐3 in nontransformed tissues and tumor lines. There is evidence that the association of C4.4A with galectin‐3 influences LN adhesion. C4.4A was described originally as a metastasis‐associated molecule. Our findings that LN1 and LN5 are C4.4A ligands, that galectin‐3 associates with C4.4A and that C4.4A ligand binding confers a migratory phenotype are well in line with the supposed metastasis association. © 2005 Wiley‐Liss, Inc.

CD44v6 is transiently expressed during T cell activation, and constitutively CD44v4-v7 expressing transgenic T cells show accelerated responses towards nominal antigens. The underlying mechanism is unknown. The mouse thymoma EL4 was transfected with CD44 standard isoform (CD44s) or CD44v6 cDNA (EL4-s, EL4-v6). Only EL4-v6 cells proliferated at an over 10-fold higher rate than untransfected cells, displayed up-regulated expression of CD69, CD25, and IL-2, and were protected from apoptosis by CD44v6 cross-linking. In the absence of any stimulus, ERK1/2 was partly phosphorylated, and phosphorylation was significantly increased by CD44v6 cross-linking. The same accounted for JNK, c-jun, and IkappaBalpha. Moreover, NF-kappaB was partly translocated into the nucleus. Instead, CD44s cross-linking induced ERK1/2, JNK, c-jun, and IkappaBalpha phosphorylation only in the context of TCR engagement. No selectively CD44v6 associated transmembrane proteins were uncovered in EL4 cells. However, CD44v6, as opposed to CD44s, did not colocalise with the TCR/CD3 complex after CD3 cross-linking. Furthermore, a CD44-associated 85-kDa protein became hypophosphorylated only after CD44v6 cross-linking. Threonine hypophosphorylation of this protein coincided with the activation of MAP and SAP kinases, which was prohibited in the presence of a phosphatase inhibitor. Thus, CD44v6, distinct to CD44s, stimulates autonomously growth and IL-2 secretion of a thymoma line and rescues cells from apoptosis.

Blockade of CD44v7 was described to cure trinitrobenzene sulfonic acid-induced colitis, a disease not developed by mice with targeted deletion of the CD44v7 exon. There was evidence for a reduction in activation-induced cell death on lamina propria lymphocytes of control as compared with CD44v7-deficient mice. To elucidate the mechanism underlying the relative apoptosis resistance of CD44v7-competent as compared with CD44v7-deficient lymphocytes, T cell activation and induction of apoptosis were analyzed on mesenteric lymph node cells and Peyer’s patch lymphocytes of CD44v7-deficient and CD44v4-v7-transgenic mice, which overexpress rat CD44v4-v7 on T lymphocytes. CD44v7 deficiency was characterized by an increase in the percentage of apoptotic cells after stimulation, increased numbers of CD95L- and CD152-positive cells, low levels of the anti-apoptotic proteins Bcl-2 and Bcl-Xl, and decreased phosphorylation of the pro-apoptotic protein BAD. Also, lymphocytes from CD44v4-v7-transge...

C4.4A is a member of the Ly6 family, with low homology to uPAR. It has been detected mainly on metastasizing carcinoma cells and proposed to be involved in wound healing. So far, C4.4A has been observed as an orphan receptor, and its functional activity has not been explored. Using recombinant rat C4.4A (rrC4.4A) made in a eukaryotic expression system, we demonstrate by immunohistology that C4.4A ligands are strongly expressed in tissues adjacent to squamous epithelia of, e.g., tongue and esophagus, the expression pattern partly overlapping with laminin (LN) and complementing the C4.4A expression that is found predominantly on the basal layers of squamous epithelium. ELISA screening of several components of the extracellular matrix revealed selective binding of rrC4.4A to LN1 and LN5 and that transfection of the BSp73AS tumor line with C4.4A cDNA (BSp73AS‐1B1) promoted LN1 and LN5 binding. Binding of BSp73AS‐1B1 to LN5 and, less markedly, LN1 induced spreading, lamellipodia formatio...