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J-C Soria

Publications and source records attributed to J-C Soria.

15 recordsLinked to original sources
PubMed2006

Tumour stem cell-targeted treatment: elimination or differentiation.

A wide range of studies suggest that most cancers are clonal and may represent the progeny of a single cell, a cancer stem cell (CSC) endowed with the capacity to maintain tumour growth. The concept of a cancer stem cell emerged decades ago, and the haematopoietic system is where it has mostly gained ground. More recently, CSC have been described in breast cancer and brain tumours. Growing evidence suggests that pathways regulating normal stem cell self-renewal and differentiation are also present in cancer cells and CSC. Malignant tumours can be viewed as an abnormal organ in which a small population of tumourigenic cancer stem cells have escaped the normal limits of self-renewal giving rise to abnormally differentiated cancer cells that contribute to tumour progression and growth. This new model has important implications for the study and treatment of cancer. Understanding the molecular circuitry which contributes to the maintenance of stem cells may provide an insight into the molecular mechanisms of cancer and thus new approaches for elimination or differentiation therapy. Therapies targeting CSC should focus on pathways such as Wnt, Shh and Notch which are required for the maintenance of cancer stem cells, but also on the ABC transporter family and other specific properties of cancer stem cells.

Cell Differentiation↗
PubMed2006

hTERT: a novel endogenous inhibitor of the mitochondrial cell death pathway.

hTERT is the catalytic subunit of the telomerase and is hence required for telomerase maintenance activity and cancer cell immortalization. Here, we show that acute hTERT depletion has no adverse effects on the viability or proliferation of cervical and colon carcinoma cell lines, as evaluated within 72 h after transfection with hTERT-specific small interfering RNAs (siRNAs). Within the same time frame, hTERT depletion facilitated the induction of apoptotic cell death by cisplatin, etoposide, mitomycin C and reactive oxygen species, yet failed to sensitize cells to death induction via the CD95 death receptor. Experiments performed with p53 knockout cells or chemical p53 inhibitors revealed that p53 was not involved in the chemosensitizing effect of hTERT knockdown. However, the proapoptotic Bcl-2 family protein Bax was involved in cell death induction by hTERT siRNAs. Depletion of hTERT facilitated the conformational activation of Bax induced by genotoxic agents. Moreover, Bax knockout abolished the chemosensitizing effect of hTERT siRNAs. Inhibition of mitochondrial membrane permeabilization by overexpression of Bcl-2 or expression of the cytomegalovirus-encoded protein vMIA (viral mitochondrial inhibitor of apoptosis), which acts as a specific Bax inhibitor, prevented the induction of cell death by the combination of hTERT depletion and chemotherapeutic agents. Altogether, our data indicate that hTERT inhibition may constitute a promising strategy for facilitating the induction of the mitochondrial pathway of apoptosis.

Antineoplastic Agents↗
PubMed2005

Differential expression of biomarkers in lung adenocarcinoma: a comparative study between smokers and never-smokers.

BACKGROUND: Non-small-cell lung cancer arising in never-smokers is usually of adenocarcinoma subtype. The oncogenic pathway of such tumors is poorly understood. To better define the biological characteristics of these tumors, we have compared the expression of a panel of epidermal growth factor receptor (EGFR)-related biomarkers in lung adenocarcinomas from smokers versus those in never-smokers. PATIENTS AND METHODS: Using immunohistochemical analysis, we retrospectively analyzed EGFR, pAKT, PTEN, Ki-67, p27 and hTERT expression in specimens from 190 patients with completely resected lung adenocarcinomas (43 never-smokers and 147 smokers). These analyses were performed on tissue microarrays. RESULTS: EGFR expression was higher in tumors from smokers (P < 0.01), while pAKT was overexpressed mainly in tumors from never-smokers (P = 0.01). As expected, the tumors from smokers presented a higher expression of Ki-67 and a more frequent loss of expression of p27 (P < 0.01). In a multivariate model, two biological factors (p27 and Ki-67) and two clinical factors (age and sex) showed independent significant correlation with never-smoking status. CONCLUSIONS: Lung adenocarcinomas in never-smokers have a very distinct immunohistochemical expression profile of EGFR-related biomarkers as compared with lung adenocarcinomas in smokers. High levels of EGFR and Ki-67 are observed in smokers, while never-smokers are characterized by high levels of pAKT and p27.

Adenocarcinoma↗
PubMed2005

[Targeting angiogenesis in oncology].

Advances in biology have lead to the characterization of the molecular mechanisms underlying angiogenesis, a crucial process of tumor growth. Tumor cells secrete various growth factors, including VEGF, which activate endothelial cells to form new blood vessels. Numerous drugs, at present in clinical development, interfere with the molecular mediators of angiogenesis. The death of neovessels achieved by some of such compounds allows reduction in tumor size. This review describes many angiogenesic inhibitors which mechanisms of action are quite diverse.

Angiogenesis Inducing Agents↗
PubMed2005

Molecular prognostic factors in resectable non-small cell lung cancer.

Lung cancer retains the leading position in cancer-related deaths in the western countries. Non-small cell lung cancer (NSCLC) comprises more than 80% of lung cancers, and complete surgical resection of primary tumors in early-stage disease is the only potentially curative treatment. One area of intense research on early-stage NSCLC is the identification of molecular markers to complement TNM staging to fully assess the prognosis of patients and to define innovative strategies. Numerous prognostic factors have been identified in patients with early-stage NSCLC that might enable classification of such patients into different subsets corresponding to different risks of recurrence following complete resection. Most of the markers are proteins that can be detected by immunohistochemistry assays based on the antigen-antibody reaction. The present review aims at providing a panorama on classical as well as new prognostic markers. Of special interest are some molecular factors, already or currently tested from a prognostic point of view, that might also become good candidates for predicting treatment efficacy.

Biomarkers, Tumor↗
PubMed2005

Assessing abnormal gene promoter methylation in paraffin-embedded sputum from patients with NSCLC.

Aberrant methylation of CpG islands is an important pathway for regulation of gene expression. Recent data suggest that epigenetic abnormalities may occur very early in lung carcinogenesis. We studied the promoters of the four genes, HOX A9, p16(INK4a) (p16), MAGE A1 and MAGE B2 by methylation-specific PCR in matched normal tissue, tumour, and cytological negative sputum samples obtained from 22 patients with non-small cell lung cancer (NSCLC). We further report methylation abnormalities in sputum samples from 56 smokers with differential cytology readouts (negative, inflammatory changes, suspicious, and cancer). Our method was successfully performed on formalin-fixed and paraffin-embedded (FFPE) samples, and was fit to study only few cells obtained by a convenient non-invasive sputum collection and handling. The promoters of MAGE A1 and MAGE B2 had abnormal methylation patterns in, respectively, 50% and 41% of the cytologically negative sputum samples from NSCLC patients, whereas methylation abnormalities of p16 was observed in 27% of negative sputum samples. Interestingly, 95.5% (21 of 22) of the cytologically negative sputum samples from NSCLC patients had abnormal methylation in at least one of the four genes indicating a high sensitivity of this marker system. Moreover, a higher frequency of methylation abnormalities was observed in sputum samples from smokers with high cytological grade compared to low cytological grade. We conclude that the identification of abnormal gene methylation of a limited number of markers in FFPE sputum samples is feasible and may be investigated as a potential system for population-based screening of early stages of lung cancer.

Aged↗
PubMed2005

Epidermal growth factor receptor signaling in colorectal cancer: preclinical data and therapeutic perspectives.

Epidermal growth factor receptor (EGFR) belongs to a family of receptors known as the ErbB family (ErbB tyrosine kinase receptors) which comprises four proteins encoded by the c-erbB proto-oncogene. EGFR is known to activate a cascade of multiple signaling pathways that facilitate tumor growth process. EGFR has been shown to be overexpressed in colorectal cancer patient populations but its prognostic value in colorectal cancer progression remains unclear. The development of a panel of EGFR inhibitors could reduce the proliferation of tumor cells when used alone or in combination with cytotoxic drugs or radiation. This review focuses on the potential role of EGFR signaling in the survival of colorectal tumor cells and the possible modulation of such signaling pathways by EGFR inhibitors so as to increase tumor control or render tumor cells more sensitive to conventional therapy.

Cell Proliferation↗
PubMed2004

ERK1/2 is activated in non-small-cell lung cancer and associated with advanced tumours.

Activation of the ERK1/2 pathway is involved in malignant transformation both in vitro and in vivo. Little is known about the role of activated ERK1/2 in non-small cell lung cancer (NSCLC). The purpose of this study was to characterise the extent of the activation of ERK1/2 by immunohistochemistry in patients with NSCLC, and to determine the relationship of ERK1/2 activation with clinicopathological variables. Specimens from 111 patients with NSCLC (stages I-IV) were stained for P-ERK. Staining for epidermal growth factor receptor (EGFR) and Ki-67 was also performed. In all, 34% of the tumour specimens showed activation for ERK1/2, while normal lung epithelial tissue was consistently negative. There was a strong statistical correlation between nuclear and cytoplasmic P-ERK staining and advanced stages (P<0.05 and P<0.001, respectively), metastatic hilar or mediastinal lymph nodes (P<0.01, P<0.001), and higher T stages (P<0.01, P<0.001). We did not find correlation of nuclear or cytoplasmic P-ERK staining with either EGFR expression or Ki-67 expression. Total ERK1/2 expression was evaluated with a specific ERK1/2 antibody and showed that P-ERK staining was not due to ERK overexpression but rather to hyperactivation of ERK1/2. Patients with a positive P-ERK cytoplasmic staining had a significant lower survival (P<0.05). However, multivariate analysis did not show significant survival difference. Our study indicates that nuclear and cytoplasmic ERK1/2 activation positively correlates with stage, T and lymph node metastases, and thus, is associated with advanced and aggressive NSCLC tumours.

Adenocarcinoma↗
PubMed2004

Detection of HER-2/neu-positive circulating epithelial cells in prostate cancer patients.

HER-2/neu may play a role in prostate carcinogenesis. The aim of this study was to use the expression of HER-2/neu as a molecular marker for the detection of circulating tumour cells (CTCs) in the blood of patients with prostate cancer (PC). Blood samples were collected from 42 patients with PC and nine healthy volunteers. Immunomagnetic beads were used to harvest epithelial cells from peripheral blood mononuclear cells. Total RNA was extracted and reverse transcribed before analysis by real-time PCR with HER-2/neu-specific primers. CTCs were HER-2/neu positive in six out of 11 (54%) patients with metastatic disease and in three out of 31 (9.6%) patients with localised PC (P=0.004). In blood samples from nine healthy volunteers, we detected no expression of HER-2/neu. The present method appears to be minimally invasive, highly sensitive and a specific approach for detecting CTCs in PC. Furthermore, it may help better target HER-2/neu in advanced PC.

Adult↗
PubMed2004

Chemokine receptor CXCR4 and early-stage non-small cell lung cancer: pattern of expression and correlation with outcome.

BACKGROUND: The expression of CXCR4 has been implicated in metastatic dissemination in different models of breast cancer and melanoma. In the present study, we evaluated CXCR4 expression in non-small-cell lung cancer (NSCLC) and the relationship between CXCR4 expression and the prognosis of stage I disease. PATIENTS AND METHODS: Using immunohistochemical analysis, we retrospectively analyzed CXCR4 expression in specimens from 61 patients with completely resected pathologically confirmed stage I NSCLC for whom clinical follow-up data were available. RESULTS: In the present study, we have shown that: CXCR4 is expressed by tumor cells in stage I NSCLC; CXCR4 is located in the nucleus and/or in the cytoplasm of tumor cells; strong nuclear staining was observed in 17 cases (29.8%); patients whose tumors had CXCR4-positive nuclear staining had a significantly longer duration of survival than patients whose tumors had no nuclear expression (P = 0.039, log-rank test). Interestingly, the 5-year metastasis rates were 23.5% and 34.1% in patients with CXCR4-positive and CXCR4-negative nuclear expression, respectively (P = 0.2). CONCLUSION: Strong CXCR4-positive nuclear staining was associated with a significantly better outcome in early-stage NSCLC. The mechanisms underlying this clinically and biologically important finding need to be further explored.

Adult↗
PubMed2003

Long-term survival of patients given hormonal therapy for metastatic endometrial stromal sarcoma.

Endometrial stromal sarcoma (ESS) is a rare neoplasm, mainly observed in premenopausal women. We describe two women 44 and 34 years old at the time ESS diagnosis, who developed lung metastases 3 and 6 years, respectively, after initial treatment: hysterectomy without (case 1) or with oophorectomy (case 2), followed by hormone replacement therapy (HRT) for the latter. Their estrogen (ER) and progesterone receptors (PR) were analyzed biochemically in metastatic lung tissue, yielding respective concentrations of ER 242 and 184, and PR 910 and 100 fmol/mg of cytosol protein. Both patients started treatment with the aromatase inhibitor aminoglutethimide (500 mg qid) after surgery for the first patient and after stopping HRT for the second. Under aromatase-inhibitor therapy, both patients achieved a complete response, patient 1 remains disease- free with 14+ years of follow-up, and patient 2 with 7+ years. Our data suggest that an aromatase inhibitor may be an effective treatment for ESS. Furthermore, routine ER and PR analyses could be useful to predict the response to hormonal therapy in ESS.

Adult↗