Clinical significance of toll-like receptor 3, 4, and 9 in gastric cancer.

Toll-like receptors (TLRs) have raised an extraordinary interest in cancer research due to their role in tumor progression. By activating the production of several biological factors, TLRs drive an inflammatory response and activate the adaptive immune system. The aim of this study was to investigate the expression and clinical relevance of TLR3, TLR4, and TLR9 in gastric cancer. For this purpose, an immunohistochemical study on cancer specimens from 106 patients with gastric cancer was performed using tissue arrays and specific antibodies against TLR3, TLR4, and TLR9. The results indicate that gastric carcinomas samples show high expression of TLR3, TLR4, and TLR9 by cancer cells. The expression of TLR3 by cancer cells was significantly associated with a poor overall survival in patients with resectable tumors. Moreover, in patients with resectable tumors and lymph node invasion, a high TLR3 expression defines a population with even worse prognosis. Therefore, TLR3 may have clinical interest as indicator of tumor aggressiveness and as a prognostic indicator in gastric cancer.

Expression and prognostic significance of fibronectin and matrix metalloproteases in breast cancer metastasis.

AIMS: Fibronectin (FN) has attracted interest in cancer research, owing to its role in tumour progression. The aims of this study were to investigate the expression and clinical relevance of FN in breast cancer, and to explore its relationship with the expression of matrix metalloproteases (MMPs) and their inhibitors (TIMPs). METHODS AND RESULTS: An immunohistochemical study was performed using tumours from 110 breast cancer patients, with tissue arrays and specific antibodies against FN, MMP-7, MMP-9, MMP-11, TIMP-1, and TIMP-2. The results indicated that FN expression was related to tumour size, histological grade, and MMP-9 expression. Tumours with high FN expression by tumour cells were significantly associated with a higher probability of metastasis, poorer overall survival, and expression of MMP-7, MMP-9, MMP-11, TIMP-1 and TIMP-2 by mononuclear inflammatory cells (MICs). In addition, the combination of FN expression by tumour cells and MMP-11 by MICs was strongly associated with distant metastasis development. CONCLUSIONS: Breast carcinomas with distant metastasis frequently have tumour cells expressing intracellular FN. There is a strong association between FN expression by tumour cells and MMP or TIMP expression by stromal MICs, and this may represent crosstalk that is of prognostic relevance in breast cancer.

Relationship between the inflammatory molecular profile of breast carcinomas and distant metastasis development.

Inflammatory conditions may promote tumor progression and aggressiveness. In previous reports, we found a group of breast cancer tumors characterized by metalloprotease-11 (MMP-11) expression by intratumoral mononuclear inflammatory cells (MICs), which was associated with distant metastasis development. Thus, in the present study we evaluated the relationship between MMP-11 expression by MICs, distant metastasis development, and a wide panel of inflammatory factors in breast carcinoma. In an initial approach, we analyzed 65 factors associated with tumor progression and inflammation, in a tumor population classified in good or bad prognosis, based on MMP-11 expression by intratumoral MICs. The most differentially expressed factors were then analyzed in a wider tumor population classified according to MMP-11 expression by MICs and also according to metastasis development. These analyses were carried out by Real-time PCR. The results showed that of the 65 starting factors analyzed, those related with MMP-11 expression by MICs were: IL-1, -5, -6, -8, -17, -18, MMP-1, TIMP-1, ADAM-8, -10, -15, -23, ADAMTS-1, -2, -15, Annexin A2, IFNß, Claudin-3, CCL-3, MyD88, IRAK-4 and NFκB. Of them, factors more differentially expressed between both groups of tumors were IL-1, IL-5, IL-6, IL-17, IFNß and NFκB. Thereafter, we confirmed in the wider tumor population, that there is a higher expression of those factors in tumors infiltrated by MMP-11 positive MICs. Altogether these results indicate that tumors developing worse prognosis and identified by MMP-11 expression by intratumoral MICs, shows an up-regulation of inflammatory-related genes.

Duodenal expression of Toll-like receptors and interleukins are increased in both children and adult celiac patients.

BACKGROUND: Toll-like receptors (TLRs) have achieved an extraordinary amount of interest in inflammatory diseases due to their role in the inflammatory activation. By activating the production of several biological factors, TLRs induce type I interferons and other cytokines, which drive the inflammatory response and activate the adaptive immune system. AIMS: The aim of this study was to investigate and compare the expression and clinical relevance of TLRs and interleukins in pediatric and adult celiac disease (CD), defined as intolerance to dietary proteins found in wheat, barley, and rye. METHODS: The expression levels of TLR3, TLR4, and TLR7, interleukins, and different transcription factors were analyzed on duodenal biopsies from ten children and 31 adults with CD, and 21 duodenal controls biopsies without CD (ten children and 11 adults). The analyses were performed by immunohistochemistry and real-time PCR. RESULTS: There were no significant differences in the studied parameters between adults and children. TLR4 expression level was increased twofold in CD specimens compared to controls. CD patients with high levels of TLR4 also showed high levels of interleukins (IL1, IL6, IL8, and IL17) as well as transcription factors (IRAK4, MyD88, and NF-κB). CONCLUSIONS: TLR4 expression is associated with CD independently of age at diagnosis. Pediatric patients and adult patients have a similar inflammatory profile, making it possible to treat both with the same immunological therapy in the future.

Clinical significance of myosin in colorectal cancer.

Myosin has raised an interest in cancer research because of its role in tumor progression. The aim of this study was to investigate the expression and clinical relevance of myosin in colorectal cancer (CC). Myosin was detected in CC tumors with recurrence using matrix-assisted laser desorption/ionization time-of-flight analysis. An immunohistochemical study was performed using tissue arrays and specific antibodies against myosin heavy chain. Determinations on cancer specimens from 91 patients with resectable CCs were performed. The minimum follow-up period was of 12.5 years for these patients without tumor recurrence. Western blot and real-time polymerase chain reaction analysis were also performed. Samples of carcinomas with recurrence showed an increased expression of myosin. Tumors with high myosin expression by tumor cell were significantly associated with higher probability of metastasis. Our results suggest that myosin expression in CCs is associated with tumor progression and metastasis development. Therefore, myosin tumor expression may contribute to an improved prognostic evaluation in patients with CC.

Relationship between metalloprotease expression in tumour and stromal cells and aggressive behaviour in prostate carcinoma: Simultaneous high-throughput study of multiple metalloproteases and their inhibitors using tissue array analysis of radical prostatectomy samples.

OBJECTIVE: The aim of this study was to detect a potential association between clinicopathological factors of prostate cancer aggressiveness and the expression of matrix metalloproteases and their inhibitors in tumour and stromal cells. MATERIAL AND METHODS: A tissue array technique and immunochemistry with specific antibodies against matrix metalloproteinases (MMPs)-1, 2, 7, 9, 11, 13, 14, and their tissue inhibitors (TIMPs)-1, 2 and 3 were used to analyse the surgical specimens of 133 patients treated by radical prostatectomy. For each antibody preparation, the cellular location of immunoreactivity was determined. RESULTS: The expression of MMP-2 was negatively associated with high tumour grade. With regard to stromal fibroblasts, TIMP-3 expression was positively associated with histological grade. MMP-7 expression was negatively associated with pretreatment serum levels of PSA, whereas MMP-13 was positively associated with higher levels of the antigen. TIMP-2 expression by mononuclear inflammatory cells correlated significantly and negatively with tumour grade. CONCLUSIONS: The expression of TIMP-3 by fibroblasts was associated with a higher Gleason score. An increased expression of MMP-13 by fibroblasts was associated with a greater preoperative level of PSA. In contrast, MMP-2 expression by tumour as well as TIMP-2 expression by peritumoral inflammatory cells was associated with less aggressive prostate carcinoma characteristics.

Collagenase-3 expression by tumor cells and gelatinase B expression by stromal fibroblast-like cells are associated with biochemical recurrence after radical prostatectomy in patients with prostate cancer.

PURPOSE: To investigate the possible clinical value of the expression of MMPs and their tissue inhibitors (TIMPs) by the different cellular types of the tumor scenario to predict biochemical recurrence in patients undergoing radical prostatectomy due clinically localized prostate cancer. METHODS: An immunohistochemical study was performed using tissue arrays and specific antibodies against MMPs-1, 2, 7, 9, 11, 13 and 14 and TIMPs-1, 2 and 3 on cancer specimens from 133 patients with clinical localized prostate carcinoma. RESULTS: Immunostaining for all the proteins studied was localized predominantly in tumor cells, but also in stromal cells in a significant percentage of prostate carcinomas, ranged from 20 to 50% for several proteins in fibroblast-like cells and in mononuclear inflammatory cells. Multivariate analysis according to a Cox model demonstrated that tumor stage (P < 0.0001) and Gleason grading (grades 7-10: 2.08 (1.1-3.9); P < 0.05) were significantly and independently associated with biochemical recurrence. Additionally, the expression of MMP-9 by fibroblast-like cells (P < 0.01) and MMP-13 by tumor cells (P < 0.05) were also variables significantly and independently associated with biochemical recurrence. CONCLUSIONS: MMP-13 expression by tumor cells and MMP-9 by stromal fibroblast-like cells were independent factors of biochemical recurrence in prostate cancer.

Study of TLR3, TLR4, and TLR9 in prostate carcinomas and their association with biochemical recurrence.

BACKGROUND: Toll-like receptors (TLRs) have garnered an extraordinary amount of interest in cancer research due to their role in tumor progression. By activating the production of several biological factors, TLRs induce type I interferons and other cytokines, which drive an inflammatory response and activate the adaptive immune system. The aim of this study was to investigate the expression and clinical relevance of TLR3, 4, and 9 in prostate cancer. METHODS: The expression levels of TLR3, TLR4, and TLR9 were analyzed on tumors from 133 patients with prostate cancer. The analyses were performed by immunohistochemistry on tissue arrays and real time-PCR. RESULTS: Cancerous cells showed high expression levels of TLRs compared with controls. Samples of carcinomas with recurrence exhibited a significant increase in the mRNA levels of TLR3, TLR4, and TLR9. In addition, the tumors that showed high TLR3 or TLR9 expression levels were significantly associated with higher probability of biochemical recurrence. CONCLUSION: TLR expression is associated with prostate cancer with recurrence and the role of TLR receptors in the biology of malignancy merits study. Therapeutic strategies to boost or block TLRs may be of interest.

Comparative study of stromal metalloproteases expression in patients with benign hyperplasia and prostate cancer.

PURPOSE: The aim of the present work was to perform a comparative study of stromal cell expressions of MMPs and TIMPs between benign and malignant prostate tissues. METHODS: An immunohistochemical study was performed using specific antibodies against metalloproteases (MMPs) -1, -2, -7, 9, 11, 13, 14 and their tissue inhibitors (TIMPs) -1, 2 and 3, on prostate specimens from 133 patients with clinical localized prostate carcinoma and from 50 patients with BPH. RESULTS: Our results showed higher percentages of expressions of MMPs and TIMPs by fibroblasts or by mononuclear inflammatory cells (MICs) in prostate carcinomas compared to these cells in BPH. The detection of MMP-2 expression by stromal fibroblasts and/or MMP-2, 9 and TIMP-3 expression by stromal MICs was associated with a 100% of specificity for diagnoses of prostate cancer. We found that the combination of MMP-2 expression by fibroblasts and/or MMP-9 by MICs and/or TIMP-2 by MICs yielded a sensitivity of 47.4%. CONCLUSIONS: Despite of a limited sensitivity (50%), the combination of MMP-TIMPs expression in stromal cells (MMP-2 by fibroblasts and TIMPs by MICs) in our study provided a specificity of 100% for prostate cancer diagnosis.

Study of TLR3, TLR4 and TLR9 in breast carcinomas and their association with metastasis.

BACKGROUND: Toll-like receptors (TLRs) have garnered an extraordinary amount of interest in cancer research due to their role in tumor progression. By activating the production of several biological factors, TLRs induce type I interferons and other cytokines, which drive an inflammatory response and activate the adaptive immune system. The aim of this study was to investigate the expression and clinical relevance of TLR3, 4 and 9 in breast cancer. METHODS: The expression levels of TLR3, TLR4 and TLR9 were analyzed on tumors from 74 patients with breast cancer. The analysis was performed by immunohistochemistry. RESULTS: Samples of carcinomas with recurrence exhibited a significant increase in the mRNA levels of TLR3, TLR4 and TLR9. Tumors showed high expression of TLRs expression levels by cancer cells, especially TLR4 and 9. Nevertheless, a significant percentage of tumors also showed TLR4 expression by mononuclear inflammatory cells (21.6%) and TLR9 expression by fibroblast-like cells (57.5%). Tumors with high TLR3 expression by tumor cell or with high TLR4 expression by mononuclear inflammatory cells were significantly associated with higher probability of metastasis. However, tumours with high TLR9 expression by fibroblast-like cells were associated with low probability of metastasis. CONCLUSIONS: The expression levels of TLR3, TLR4 and TLR9 have clinical interest as indicators of tumor aggressiveness in breast cancer. TLRs may represent therapeutic targets in breast cancer.

Comparative analysis and clinical value of the expression of metalloproteases and their inhibitors by intratumour stromal mononuclear inflammatory cells and those at the invasive front of breast carcinomas.

AIMS: Matrix metalloproteases (MMPs) and their inhibitors (TIMPs) play an essential role in the degradation of stromal connective tissue and basement membrane components. The aim of this study was to determine whether the dynamic analysis of these components can help to predict tumour aggressiveness. METHODS AND RESULTS: An immunohistochemical study was performed using tissue arrays and specific antibodies against MMPs -1, -2, -7, -9, -11, -13 and -14 and TIMPs -1, -2 and -3. More than 5000 determinations on cancer specimens from 124 patients with invasive breast cancer were performed on the tumour centre core as well as on the invasive front. Immunostaining for MMPs/TIMPs on mononuclear inflammatory cells (MICs) was evaluated. To identify specific groups of tumours with distinct expression profiles, data obtained from both MICs populations were analysed by unsupervised hierarchical cluster analysis. When compared with MICs at the invasive front, intratumour MICs more frequently showed expression of MMP-7 and -1 and TIMP-3, but less frequently expression of MMP-9 and -11 and TIMP-2. CONCLUSIONS: Our data led us to consider the need of further studies in order to identify subsets of MICs and other protein elements of the microenvironment as attractive targets for new therapeutic strategies against cancer.

Comparative study of the expression of metalloproteases and their inhibitors in different localizations within primary tumours and in metastatic lymph nodes of breast cancer.

Studies on metastasic lesions from human carcinomas are scarce. Therefore there is a need for such studies to identify the expression of the biological factors that will help in the assessment of the natural history of breast cancer. Here an immunohistochemical study was performed using tissue arrays and specific antibodies against matrix metalloproteinases (MMPs)-1, 2, 7, 9, 11, 13, 14 and tissue inhibitors of metalloproteases (TIMPs)-1, 2 and 3 in 39 patients with breast cancer. Specimens from 39 patients with node-positive carcinomas were examined and the analysis was performed at the central core of the tumour, at the invasive front, and in the metastasic axillary lymph nodes (MALNs). Global expression of MMP-1, 7 and 14, TIMP-1, and 3, were significantly higher at the centre of the tumour compared with the invasive front or the MALNs. Significantly higher expression of MMP-7 and 14, and TIMP-3, by fibroblast-like cells and mononuclear inflammatory cells (MICs) was seen in MALNs. In addition, in the tumour centre, the expression of MMP-11 and TIMP-1 and 2 by MICs, as well as TIMP-2 expression by fibroblast-like cells, were associated significantly with the occurrence of distant metastasis. In contrast, TIMP-3 expression by tumour cells or by fibroblast-like cells in this same tumour locations, as well as TIMP-1 expression by fibroblast-like cells at the invasive front, were associated significantly with poor prognosis. However, the expression of all of these biological factors in MALNs was not associated with the development of distant metastasis. Our data suggest that there is prognostic relevance to the expression of MMPs and TIMPs in the stromal cells of primary tumours, rather than to the expression of these enzymes in MALNs.

Immunohistochemical study of matrix metalloproteinases and their inhibitors in pure and mixed invasive and in situ ductal carcinomas of the breast.

We assessed differences in the patterns of expression of matrix metalloproteases and their inhibitors (tissue inhibitors of metalloproteases) in ductal carcinoma in situ alone and admixed with invasive ductal carcinomas (n = 40), as well as in pure invasive ductal carcinomas (n = 40), immunohistochemically and using tissue arrays. The invasive ductal carcinoma components showed higher expression of matrix metalloprotease-9 and -13 than did the admixed ductal carcinoma in situ, whereas stromal fibroblasts of the invasive components showed higher expression of matrix metalloprotease-2, -7, -9, -13, and -14 and tissue inhibitor of metalloprotease-1 and -3 than did fibroblasts around the neoplastic ducts of the admixed ductal carcinoma in situ. Expression of matrix metalloprotease-14 and tissue inhibitor of metalloprotease-3 was significantly higher in the mononuclear inflammatory cells of the invasive components. By contrast, matrix metalloprotease-1 expression was significantly higher in stromal cells of the ductal carcinoma in situ admixed with invasive ductal carcinoma. The pure invasive ductal carcinomas had significantly higher expression of matrix metalloprotease-1, -9, -11, and -14 and tissue inhibitor of metalloprotease-1 and -3 than the invasive ductal carcinomas admixed with ductal carcinoma in situ. Our findings indicate a significant association of matrix metalloprotease expression by the periductal stromal cells of the ductal carcinoma in situ component of mixed tumors and the occurrence of distant metastasis. Our data suggest that the molecular matrix metalloprotease/tissue inhibitor of metalloprotease profile can contribute to better characterization of early breast carcinomas.

Relationship between morphological features and kinetic patterns of enhancement of the dynamic breast magnetic resonance imaging and clinico-pathological and biological factors in invasive breast cancer.

BACKGROUND: To investigate the relationship between the magnetic resonance imaging (MRI) features of breast cancer and its clinicopathological and biological factors. METHODS: Dynamic MRI parameters of 68 invasive breast carcinomas were investigated. We also analyzed microvessel density (MVD), estrogen and progesterone receptor status, and expression of p53, HER2, ki67, VEGFR-1 and 2. RESULTS: Homogeneous enhancement was significantly associated with smaller tumor size (T1: < 2 cm) (p = 0.015). Tumors with irregular or spiculated margins had a significantly higher MVD than tumors with smooth margins (p = 0.038). Tumors showing a maximum enhancement peak at two minutes, or longer, after injecting the contrast, had a significantly higher MVD count than those which reached this point sooner (p = 0.012). The percentage of tumors with vascular invasion or high mitotic index was significantly higher among those showing a low percentage (150%) of enhancement rate (p = 0.016 and p = 0.03, respectively). However, there was a significant and positive association between the mitotic index and the peak of maximum intensity (p = 0.036). Peritumor inflammation was significantly associated with washout curve type III (p = 0.042). CONCLUSIONS: Variations in the early phase of dynamic MRI seem to be associated with parameters indicatives of tumor aggressiveness in breast cancer.

Expression of metalloproteases and their inhibitors in primary tumors and in local recurrences after mastectomy for breast cancer.

AIMS: To investigate the expression of matrix metalloproteases (MMPs) and their inhibitors (TIMPs) in patients who develop local recurrence (LR) after mastectomy. METHODS: We analyzed the expressions of MMP-1, -2, -7, -9, -11, -13, -14, TIMP-1, -2, and -3, using immunohistochemical techniques, in primary tumors from patients without tumoral recurrence (n = 50), patients who developed distant metastasis (n = 50), and from patients who develop LRs (n = 25). LRs of the latter group were also analyzed for MMPs expression. All the patients underwent mastectomy. RESULTS: Score values for all MMPs and TIMPs were significantly higher in primary tumors of patients with distant metastasis. Primary tumors from patients with LR have lower expressions of MMPs and TIMPs compared with those from patients who developed distant metastasis, and with patients without recurrence for some MMPs. Remarkably, however, primary tumors from patients with LR showed significantly higher percentage of TIMP-1 and 2 expression in stromal cells compared to primary tumors from patients with distant metastasis or primary tumors from patients without tumoral progression. Furthermore, LRs had significantly higher MMP-9 expression than their corresponding primary tumors. CONCLUSIONS: Our data indicate differences in MMPs/TIMPs expression between primary tumors of patients with LRs and of those with distant metastasis, both after mastectomy for breast cancer.

Role of annexin A2 in cellular entry of rabbit vesivirus.

The mechanisms of calicivirus attachment and internalization are not well understood, mainly due to the lack of a reliable cell-culture system for most of its members. In this study, rabbit vesivirus (RaV) virions were shown to bind annexin A2 (ANXA2) in a membrane protein fraction from HEK293T cells, using a virus overlay protein-binding assay and matrix-assisted laser desorption/ionization time-of-flight analysis. A monoclonal anti-ANXA2 antibody and small interfering RNA-mediated knockdown of ANXA2 expression in HEK293T cells reduced virus infection significantly, further supporting the role of ANXA2 in RaV attachment and/or internalization.

Effects of antioxidant vitamins on molecular regulators involved in lung hypoplasia induced by nitrofen.

INTRODUCTION: Oxidant herbicide nitrofen (2,4-dichloro-4'-nitrodiphenyl ether) induces in rat embryos congenital diaphragmatic hernia (CDH) with lung hypoplasia. The present study aims at examining whether antioxidant vitamins A, E, and C reverse the effects of the teratogen in the lungs of exposed rats and how they modify the expression of molecular regulators known to be involved in their pathogenesis. MATERIALS AND METHODS: Wet lung weight-body weight ratio, total DNA, and total protein were determined. Thyroid transcription factor 1 (TTF-1), hepatocyte nuclear factor 3beta (HNF-3beta), and surfactant protein B (SP-B) proteins were measured by immunoblot assay in lung homogenates from rat fetuses exposed in utero to either nitrofen 100 mg intragastrically or vehicle. The coexpression of these factors in the alveolar epithelium was demonstrated by immunohistochemistry. The effects of the addition of vitamins A, C, and E were assessed by comparison with analysis of variance. RESULTS: Nitrofen decreased lung weight, total DNA, and total protein. The addition of antioxidant vitamins had no effect on lung weight, but increased DNA and protein contents. TTF-1, HNF-3beta, and SP-B proteins were decreased in lung homogenates of exposed rats with CDH. The addition of antioxidant vitamins nearly normalized these values. CONCLUSIONS: The effects of nitrofen in fetal rat lungs are reversed in part by antioxidant vitamins by upregulating the expression of TTF-1, HNF-3beta, and SP-B. This approach could help to develop transplacental prenatal interventions for CDH.

Vitamin A improves Pax3 expression that is decreased in the heart of rats with experimental diaphragmatic hernia.

BACKGROUND/AIMS: Rats with nitrofen-induced congenital diaphragmatic hernia (CDH) have hypoplasia and malformations of the heart. The mechanism of action of nitrofen involves changes in neural crest signaling. Pax3 function is required for cardiac neural crest cells to complete their migration to the developing heart. Vitamin A improves heart hypoplasia. The aims of this study were to examine whether Pax3 expression is decreased in the heart of E13 E15 and E21 rats exposed to nitrofen and if vitamin A reverts this effect. MATERIAL AND METHODS: Pregnant rats received either 100 mg nitrofen or olive oil on E9.5. Each group was divided into 2 subgroups according to the subsequent treatment with intragastric vitamin A (15000 IU) or vehicle on E10.5 to E11.5. The pups were recovered on E13, E15 and E21 and the hearts were dissected out. Pax3 mRNA expression was determined by quantitative real time PCR. Comparisons among groups were made with ANOVA and Bonferroni post hoc tests with a threshold of significance of P < .05. RESULTS: Pax3 mRNA expression was significantly decreased on E13 and E15 in the hearts of nitrofen-treated embryos and it remained decreased although not significantly on E21. Vitamin A recovered this expression on E13, partially on E15 and above normal levels on E21. CONCLUSIONS: Pax3 is underexpressed in the hearts of nitrofen exposed embryonal rats on days 13th and 15th of gestation and tends to be lower than normal near term. Vitamin A up-regulates this expression on the 3 end points. The mechanism of action of Pax3 should be further investigated because it could be one of the targets for future prenatal transplacental intervention.

Effects of nitrofen and vitamins A, C and E on maturation of cultured human H441 pneumocytes.

BACKGROUND/AIM: Nitrofen (2,4-dichloro-4 -nitrodiphenyl ether), a teratogen with oxidant properties, induces congenital diaphragmatic hernia (CDH) with lung hypoplasia and delayed lung development and maturation in rat embryos. Several phenotypic features of the alveolar epithelium including surfactant proteins A and B synthesis and its regulation by transcription factors are reproduced in cultured human H441 pneumocytes. The aim of the present study was to test whether vitamins A, E and C with anti-oxidant properties were able to recover the expression of such regulators in an in vitro setting. MATERIALS AND METHODS: Cultured human H441 pneumocytes were treated with nitrofen with or without additional exposure to vitamins A, E and C. Thyroid transcription factor 1 (TTF-1), hepatocyte nuclear factor 3-beta (HNF-3beta) and hepatocyte nuclear factor 3-beta surfactant protein B (SP-B) mRNAs were measured by real-time polymerase chain reaction (RT-PCR). The cells were also immunohistochemically stained for assessment of proliferation (PCNA) and apoptosis (bis-benzimide) status and SP-B and TTF-1 protein expressions. Results were compared by ANOVA with a significant threshold of 5%. RESULTS: Nitrofen severely decreased TTF-1, HNF-3beta and SP-B mRNA expression by H441 pneumocytes in culture. Addition of vitamin E normalized the levels of the three transcripts, while vitamin A normalized only those of TTF-1 and SP-B mRNA. Vitamin C was significantly beneficial only for SP-B transcript. Nitrofen decreased proliferation and TTF-1 and SP-B protein expressions with no apparent effect on apoptosis. Additional exposure to vitamins A, C or E rescued near normal values. CONCLUSIONS: The changes induced by nitrofen in cultured H441 human pneumocytes are reverted in part by anti-oxidant vitamins by upregulating TTF-1, HNF-3beta and SP-B and stimulating proliferation and maturity in nitrofen-treated cells. These effects of anti-oxidant vitamins could be of some interest for developing new transplacental therapeutic strategies aimed at improving lung development and maturation in fetuses with CDH.

Expression of Connexin 43 in the hearts of rat embryos exposed to nitrofen and effects of vitamin A on it.

Rats with experimental congenital diaphragmatic hernia (CDH) have heart hypoplasia and conotruncal and great vessel malformations that are likely related to disturbed neural crest developmental control. Neural crest cells communicate through intercellular gap junctions whose main protein is Connexin 43 (Cx43). The migration and participation of neural crest cells in heart development is likely influenced by this protein which might be also directly involved in myocardial development. Vitamin A is beneficial for heart hypoplasia in CDH rats. The aims of this study were to examine the status of Cx43 in the heart of embryonal rats exposed to nitrofen and to assess if vitamin A reverts these effects. Pregnant rats received either 100 mg nitrofen or olive oil on E9.5. Each group was divided into two subgroups according to the subsequent treatment with intragastric vitamin A (15,000 i.u.) or vehicle on E10.5 and E11.5. The pups were recovered on E13, E15, and E21 and the hearts were dissected out and pooled. Cx43 mRNA expression was determined by quantitative real-time PCR. Comparisons among groups were made with ANOVA and Bonferroni post hoc tests with a threshold of significance of P<0.05. In control rats Cx43 mRNA was minimally expressed on E13 and E15 and fully expressed on E21. Nitrofen significantly increased Cx43 mRNA on E15. Additional treatment with vitamin A tended to moderate this increase on E15. Cx43 was overexpressed in the hearts of nitrofen-exposed embryonal rats on day E15 of gestation. Vitamin A tended to normalize this expression. The mechanism of action of Cx43 deserves further investigation.