Transoral robotic surgery for squamous cell carcinoma of the oropharynx in a primarily human papillomavirus-negative patient population.

PURPOSE: Transoral robotic surgery (TORS) is one of the main treatment options for non-locally advanced primary oropharyngeal cancer in the United States. However, its use is more limited in countries with a low incidence of human papillomavirus (HPV), such as Spain, in patients with advanced disease, and as salvage surgery. To shed light on the use and potential benefit of TORS in Spanish patients, we analyzed the functional and oncologic outcomes of TORS as both primary and salvage surgery in a primarily HPV-negative population which is representative of oropharyngeal squamous cell carcinoma (OPSCC) patients in Spain. MATERIAL AND METHODS: This is a retrospective analysis of prospectively collected data on OPSCC patients treated with TORS at our center between February 2017 and February 2019. RESULTS: Fifty-four OPSCC patients were included; 79.6% were males and 80.5% were HPV negative. Median age was 62 years. Primary surgery was performed on 73.7% (48.1% stage I-II; 51.9% stage III-IV) and salvage surgery on 25.9% of patients. Positive margin rates were 4.3% for T1-2 and 25.8% for T3-4. None of the stage I-II patients and 27.7% of stage III-IV patients required adjuvant treatment. Reconstructive surgery was performed in 19.2% of all patients. Normal swallowing was achieved in 92.7% of patients at 6 months after surgery. 1- and 2-year survival rates for all patients were 94.5% and 89%, respectively. The overall complication rate was 16.1%. Bleeding occurred in 11.5% of patients. Longer hospitalization time was associated with surgical complications (P = 0.03) and reconstructive surgery (P = 0.03) but not with salvage surgery. CONCLUSION: TORS is a safe and effective treatment for HPV-negative T1-2 OPSCC patients. The positive margin rate was worse in T3-4 patients, indicating the need for careful patient selection in this subgroup.

Prevalencia de infecciones osteoarticulares por enterobacterias productoras de ß-lactamasas de espectro extendido / Prevalence of osteoarticular infections by Enterobacteria producing extended-spectrum ß-lactamases

Resumen: Introducción: Las infecciones por enterobacterias productoras de β-lactamasas de espectro extendido (BLEEs) ocasionan una gran carga a los sistemas de salud. Poco se conoce de las infecciones osteoarticulares, por lo que este trabajo estudió la prevalencia de estas infecciones en un hospital de tercer nivel. Material y métodos: Estudio de prevalencia en pacientes de un servicio de traumatología durante 2016, con criterios de infección proporcionados por el CDC de Atlanta, Georgia. Se utilizó el sistema VITEK® 2 AST-N272 (bioMérieux) para la identificación bacteriana a nivel de especie y para las pruebas de susceptibilidad antimicrobiana. Resultados: Se reportaron 7.85% (n = 86) con infecciones osteoarticulares; 22.09% (n = 19) fueron por enterobacterias BLEEs. Con un promedio de 77.1 días de hospitalización (DE 37.7) (46-200 días); el aislamiento del microorganismo se produjo 15 días posteriores al ingreso; 16 (84.2%) pacientes presentaron osteomielitis, tres (15.8%) tuvieron infección protésica de rodilla o cadera. El promedio de días de tratamiento fue de 60 días (21-129 días); 18 pacientes (94.7%) fueron dados de alta con resolución de su cuadro infeccioso; un paciente falleció con infección sobreagregada por neumonía debida a K. pneumoniae resistente a carbapenémicos. Discusión: La prevalencia de infecciones osteoarticulares por enterobacterias BLEEs no se pudo calcular con precisión, pero consideramos que se encuentra dentro de lo esperado, las medidas de control de infecciones requieren tener estándares más elevados y falta desarrollar programas de uso racional de antimicrobianos para controlar la aparición de estas patologías.

Abstract: Introduction: Infections of enterobacteria producing extended-spectrum ß-lactamases place a heavy burden on health systems. Little is known in osteoarticular infections, so this work studied the prevalence of these infections in a third-level hospital. Material and methods: Prevalence study in patients of a Traumatology Service during 2016, with infection criteria provided by the CDC in Atlanta, Georgia. The VITEK® 2 AST-N272 (bioMérieux) system was used for bacterial identification at the species level and for antimicrobial susceptibility tests. Results: 7.85% (n = 86) were reported with osteoarticular infections; 22.09% (n = 19) were by enterobacteria BLEEs. An average of 77.1 days of hospitalization (SD 37.7) (46-200 days); isolation of the microorganism occurred 15 days after entry. Sixteen (84.2%) patients had osteomyelitis, three (15.8%) had a prosthetic knee or hip infection. The average number of treatment days was 60 days (21-129 days). Eighteen patients (94.7%) were discharged with resolution of their infectious picture; one patient died with infection over aggregated pneumonia due to carbapenem-resistant K. pneumoniae. Discussion: The prevalence of osteoarticular infections by enterobacteria BLEEs could not be accurately calculated, but we consider it to be within what is expected, infection control measures require higher standards and there is a lack of development programs to use antimicrobials rationally to control the emergence of these pathologies.

Interferon-Induced Transmembrane Protein 1 Restricts Replication of Viruses That Enter Cells via the Plasma Membrane.

The acute antiviral response is mediated by a family of interferon-stimulated genes (ISGs), providing cell-intrinsic immunity. Mutations in genes encoding these proteins are often associated with increased susceptibility to viral infections. One family of ISGs with antiviral function is the interferon-inducible transmembrane proteins (IFITMs), of which IFITM3 has been studied extensively. In contrast, IFITM1 has not been studied in detail. Since IFITM1 can localize to the plasma membrane, we investigated its function with a range of enveloped viruses thought to infect cells by fusion with the plasma membrane. Overexpression of IFITM1 prevented infection by a number of Paramyxoviridae and Pneumoviridae, including respiratory syncytial virus (RSV), mumps virus, and human metapneumovirus (HMPV). IFITM1 also restricted infection with an enveloped DNA virus that can enter via the plasma membrane, herpes simplex virus 1 (HSV-1). To test the importance of plasma membrane localization for IFITM1 function, we identified blocks of amino acids in the conserved intracellular loop (CIL) domain that altered the subcellular localization of the protein and reduced antiviral activity. By screening reported data sets, 12 rare nonsynonymous single nucleotide polymorphisms (SNPs) were identified in human IFITM1, some of which are in the CIL domain. Using an Ifitm1-/- mouse, we show that RSV infection was more severe, thereby extending the range of viruses restricted in vivo by IFITM proteins and suggesting overall that IFITM1 is broadly antiviral and that this antiviral function is associated with cell surface localization.IMPORTANCE Host susceptibility to viral infection is multifactorial, but early control of viruses not previously encountered is predominantly mediated by the interferon-stimulated gene (ISG) family. There are upwards of 300 of these genes, the majority of which do not have a clearly defined function or mechanism of action. The cellular location of these proteins may have an important effect on their function. One ISG located at the plasma membrane is interferon-inducible transmembrane protein 1 (IFITM1). Here we demonstrate that IFITM1 can inhibit infection with a range of viruses that enter via the plasma membrane. Mutant IFITM1 proteins that were unable to localize to the plasma membrane did not restrict viral infection. We also observed for the first time that IFITM1 plays a role in vivo, and Ifitm1-/- mice were more susceptible to viral lung infection. These data contribute to our understanding of how ISGs prevent viral infections.

Tetraspanin CD82 regulates bone marrow homing of acute myeloid leukemia by modulating the molecular organization of N-cadherin.

Communication between acute myeloid leukemia (AML) and the bone marrow microenvironment is known to control disease progression. Therefore, regulation of AML cell trafficking and adhesion to the bone marrow is of significant interest. In this study, we demonstrate that differential expression of the membrane scaffold CD82 modulates the bone marrow homing of AML cells. By combining mutational analysis and super-resolution imaging, we identify membrane protein clustering by CD82 as a regulator of AML cell adhesion and bone marrow homing. Cluster analysis of super-resolution data indicates that N-linked glycosylation and palmitoylation of CD82 are both critical modifications that control the microdomain organization of CD82 as well as the nanoscale clustering of associated adhesion protein, N-cadherin. We demonstrate that the inhibition of CD82 glycosylation increases the molecular packing of N-cadherin and promotes the bone marrow homing of AML cells. In contrast, we find that the inhibition of CD82 palmitoylation disrupts the formation and organization of N-cadherin clusters and significantly diminishes bone marrow trafficking of AML. Taken together, these data establish a mechanism where the membrane organization of CD82, through specific posttranslational modifications, regulates N-cadherin clustering and membrane density, which impacts the in vivo trafficking of AML cells. As such, these observations provide an alternative model for targeting AML where modulation of protein organization within the membrane may be an effective treatment therapy to disrupt the bone marrow homing potential of AML cells.

Clinical evidence of the role of the cerebellum in the suppression of overt articulatory movements during reading. A study of reading in children and adolescents treated for cerebellar pilocytic astrocytoma.

It has been suggested that the cerebellum is involved in reading acquisition and in particular in the progression from automatic grapheme-phoneme conversion to the internalization of speech required for silent reading. This idea is in line with clinical and neuroimaging data showing a cerebellar role in subvocal rehearsal for printed verbalizable material and with computational "internal models" of the cerebellum suggesting its role in inner speech (i.e. covert speech without mouthing the words). However, studies examining a possible cerebellar role in the suppression of articulatory movements during silent reading acquisition in children are lacking. Here, we report clinical evidence that the cerebellum plays a part in this transition. Reading performances were compared between a group of 17 paediatric patients treated for benign cerebellar tumours and a group of controls matched for age, gender, and parental socio-educational level. The patients scored significantly lower on all reading, but the most striking difference concerned silent reading, perfectly acquired by almost all controls, contrasting with 41 % of the patients who were unable to read any item silently. Silent reading was correlated with the Working Memory Index. The present findings converge with previous reports on an implication of the cerebellum in inner speech and in the automatization of reading. This cerebellar implication is probably not specific to reading, as it also seems to affect non-reading tasks such as counting.

Sedation with sevoflurane in postoperative cardiac surgery: influence on troponin T and creatinine values.

INTRODUCTION: To compare the potential beneficial effects on markers of myocardial injury (troponin T) and renal function between sedation with sevoflurane vs propofol after cardiac surgery using extracorporeal cardiopulmonary bypass. METHODS: A prospective study with sequential selection of patients undergoing coronary or coronary and valve cardiac surgery. Intraoperative anesthesia consisted in sevoflurane and remifentanil, while in the postoperative period patients were divided in two groups to receive sedation with either sevoflurane through the AnaConDa© system or propofol. The patients were sedated during a minimum of 120minutes. Markers of myocardial injury and plasmatic creatinine were measured 4, 12, 24, and 48hours after surgery. RESULTS: Data from 129patients, 62sedated with propofol and 67with sevoflurane, were analyzed. The analysis of the troponin T levels showed differences 12 and 48 hours after admission. Mean values at 12hours were 0.89 (standard deviation 0.55) µg.L(-1) in the propofol group and 0.69 (standard deviation 0.40) µg. L(-1)in the sevoflurane group (p = 0.026). TnT levels at 48hours were 0.60 (standard deviation 0.46) µg.L-(1)in the propofol group and 0.37 (standard deviation 0.26) µg.L(-1)in the sevoflurane group (p = 0,007). No differences were found in the groups in the creatinine levels before discharge. CONCLUSIONS: The post-operative sedation with sevoflurane after cardiac surgery with cardiopulmonary bypass is a valid alternative to propofol. It does not increase the number of side effects related to kidney damage in patients with no prior renal disease, leading to reduced troponin T levels 12and 48hours after admission.

The small GTPase RhoA regulates the expression and function of the sodium channel Nav1.5 in breast cancer cells.

Voltage-gated Na+ channels (VGSCs) are highly expressed in several types of carcinomas including breast, prostate and lung cancers as well as in mesothelioma and cervical cancers. Although the VGSCs activity is considered crucial for the potentiation of cancer cell migration and invasion, the mechanisms responsible for their functional expression and regulation in cancer cells remain unclear. In the present study, the role of the small GTPase RhoA in the regulation of expression and function of the Nav1.5 channel in the breast cancer cell lines MDA-MB 231 and MCF-7 was investigated. RhoA silencing significantly reduced both Nav1.5 channel expression and sodium current indicating that RhoA exerts a stimulatory effect on the synthesis of an active form of Nav1.5 channel in cancer cells. The inhibition of Nav1.5 expression dramatically reduced both cell invasion and proliferation. In addition, a decrease of RhoA protein levels induced by Nav1.5 silencing was observed. Altogether, these findings revealed: i) the key role of the small GTPase RhoA in upregulation of Nav1.5 channel expression and tumor aggressiveness, and ii) the existence of a positive feedback of Nav1.5 channels on RhoA protein levels.

The soluble fragment of VE-cadherin inhibits angiogenesis by reducing endothelial cell proliferation and tube capillary formation.

Vascular endothelial-specific cadherin (VE-cadherin) is an endothelial cell-specific adhesion molecule, localized at cell-cell contact sites. It is involved in physiological and pathological angiogenesis. In this study, we showed that in vitro a soluble N-terminal fragment of VE-cadherin (EC1-3) corresponding to cadherin 1-3 ectodomains inhibited vascular endothelial growth factor-stimulated endothelial cell proliferation and capillary tube structure formation in the matrigel model. In vivo, EC1-3 was tested in a murine colon cancer model. EC1-3-expressing colon cancer C51 cells were subcutaneously grafted into nude mice, and tumor growth and angiogenesis were evaluated. At day 33, the mean volume of the tumors developed was reduced (510±104 versus 990±120 mm(3) for control). Similarly, injection of EC1-3 virus-producing cells into established C51 tumors resulted in an inhibition by 33% of tumor growth. Immunohistological staining of vessels on tumor sections showed a significantly reduced intratumoral angiogenesis. Furthermore, EC1-3 did not induce vessel injury in the lung, liver, spleen, heart and brain in the mice. These results suggest that the soluble N-terminal fragment of VE-cadherin EC1-3 could exert an antitumoral effect by targeting tumor angiogenesis, which included blocking endothelial cell proliferation and capillary tube formation with no obvious toxicity on normal organs.

[Usefulness of a rapid serum interleukin-6 test combined with C-reactive protein to predict sepsis in newborns with suspicion of infection]. / Utilidad de un test rápido de interleuquina-6 sérico combinado con proteína C reactiva para predecir la sepsis en recién nacidos con sospecha de infección.

AIM: To evaluate the diagnostic value of interleukin-6 (IL-6) to predict the likelihood of neonatal sepsis in order to design an algorithm to decide antibiotic therapy. METHODS: IL-6 and C-reactive protein (CRP) were determined in 42 newborns with clinical suspicion of infection. Newborns were classified as a confirmed, probable or no infection, based on the results of cultures, chest X-rays and the involvement of four or more clinical areas on a scale of eight. Samples for IL-6 were collected in the initial assessment and frozen until its determination at the end of the study. Blinded IL-6 measurements were performed using a rapid test. Receiver operator characteristics curves (ROC) for CRP and IL-6 versus infection (confirmed or probable) were determined. RESULTS: Among the 42 cases included in the study 11 (26.2%) were classified as confirmed or probable infection. The area under curve (AUC) for IL-6 was 0.9, with a cut-off value of 53 pg/ml: sensitivity 90.91%, specificity 80%, positive predictive value (PPV) 62.5% and negative (NPV) 96% The level of IL-6>96 pg/ml and/or the combination of IL-6>53+CRP>13.3 mg/l, were the markers that best predicted infection: specificity 100% and PPV: 100%. CONCLUSIONS: Assessment of IL-6 could allow withholding or early discontinuation of antibiotics in newborns with IL-6<54 pg/ml. In cases with IL-6>96 pg/ml and/or IL-6>53+ CRP>13.3, antibiotics should be started promptly, given the high likelihood of infection. Implementation of an algorithm based on the determination of IL-6 and CRP, in the initial assessment of the newborn with clinical suspicion of infection, could reduce unnecessary antibiotic therapy.

Vasculogenic mimicry of acute leukemic bone marrow stromal cells.

Angiogenesis is thought to be involved in the development of acute leukemia (AL). We investigated whether bone marrow stromal cells (BMSCs) derived from stem cells might be responsible for the increase in microvascular density (MVD), and compared 13 bone marrow samples from AL patients with 23 samples from patients in complete remission (controls). We demonstrated that AL-derived BMSC secreted more insulin growth factor-1 (IGF-1) and SDF-1alpha than controls. In addition, in contrast to normal adherent BMSCs, adherent BMSCs derived from CD133+/CD34+ stem cells from AL patients were able to form capillary-like structures ('vasculogenic mimicry') on Matrigel. The increase in vasculogenic mimicry occurred through PI3 kinase and rho GTPase pathway as inhibitors of these signaling pathways (wortmannin and GGTI-298, respectively) were able to reduce or prevent capillary tube formation. In normal BMSC, addition of exogenous IGF-1 generated capillary-like tubes through the same pathway as observed spontaneously in AL-derived BMSC. The involvement of IGF-1 in the mimicry process was confirmed by the addition of a neutralizing antibody against IGF-1R or a IGF-1R pathway inhibitor (picropodophyllin). In conclusion, AL-derived BMSC present functional abnormalities that may explain the increase in MVD in the bone marrow of AL patients.

Elastokine-mediated up-regulation of MT1-MMP is triggered by nitric oxide in endothelial cells.

Membrane-type I matrix metalloproteinase (MT1-MMP) has been previously reported to be up-regulated in human microvascular endothelial cell-1 line (HMEC) by elastin-derived peptides (elastokines). The aim of the present study was to identify the signaling pathways responsible for this effect. We showed that elastokines such as (VGVAPG)(3) peptide and kappa elastin induced nitric oxide (NO) production in a time-, concentration- and receptor-dependent manner as it could be abolished by lactose and a receptor-derived competitive peptide. As evidenced by the use of NO synthase inhibitors, elastokine-mediated up-regulation of MT1-MMP and pseudotube formation on Matrigel required NO production through activation of the PI(3)-kinase/Akt/NO synthase and NO/cGMP/Erk1/2 pathways. Elastokines induced both PI(3)-kinase p110gamma sub-unit, Akt and Erk1/2 activation, as shown by a transient increase in phospho-Akt and phospho-Erk1/2, reaching a maximum after 5 and 15 min incubation, respectively. Inhibitors of PI(3)-kinase and MEK1/2 suppressed elastokine-mediated MT1-MMP expression at both the mRNA and protein levels, and decreased the ability of elastokines to accelerate pseudotube formation. Besides, elastokines mediated a time- and concentration-dependent increase of cGMP, suggesting a link between NO and MT1-MMP expression. This was validated by the use of a guanylyl cyclase inhibitor, a NO donor and a cGMP analog. The guanylyl cyclase inhibitor abolished the stimulatory effect of elastokines on MT1-MMP expression. Inversely, the cGMP analog, mimicked the effect of both elastokines and NO donor in a concentration- and time-dependent manner. Overall, our results demonstrated that such elastokine properties through NO and MT1-MMP may be of importance in the context of tumour progression.

Intravenous delivery of anti-RhoA small interfering RNA loaded in nanoparticles of chitosan in mice: safety and efficacy in xenografted aggressive breast cancer.

Overexpression of RhoA in cancer indicates a poor prognosis, because of increased tumor cell proliferation and invasion and tumor angiogenesis. We showed previously that anti-RhoA small interfering RNA (siRNA) inhibited aggressive breast cancer more effectively than conventional blockers of Rho-mediated signaling pathways. This study reports the efficacy and lack of toxicity of intravenously administered encapsulated anti-RhoA siRNA in chitosan-coated polyisohexylcyanoacrylate (PIHCA) nanoparticles in xenografted aggressive breast cancers (MDA-MB-231). The siRNA was administered every 3 days at a dose of 150 or 1500 microg/kg body weight in nude mice. This treatment inhibited the growth of tumors by 90% in the 150-microg group and by even more in the 1500-microg group. Necrotic areas were observed in tumors from animals treated with anti-RhoA siRNA at 1500 microg/kg, resulting from angiogenesis inhibition. In addition, this therapy was found to be devoid of toxic effects, as evidenced by similarities between control and treated animals for the following parameters: body weight gain; biochemical markers of hepatic, renal, and pancreatic function; and macroscopic appearance of organs after 30 days of treatment. Because of its efficacy and the absence of toxicity, it is suggested that this strategy of anti-RhoA siRNA holds significant promise for the treatment of aggressive cancers.

Malignant hematopoietic cells induce an increased expression of VEGFR-1 and VEGFR-3 on bone marrow endothelial cells via AKT and mTOR signalling pathways.

Angiogenesis plays a significant role in a variety of malignant hematologic diseases, and it is recognized that it has prognostic value. However, the cellular mechanisms by which malignant hematologic cells induce angiogenesis are not well understood. In order to investigate the role of cells from B-cell chronic lymphocytic leukemia (B-CLL) and multiple myeloma (MM) in angiogenesis on human bone marrow endothelial cells (HBMEC), we analyzed the impact of factors secreted by B-CLL cells and by MM cells on HBMEC capillary tube formation on matrigel. It was found that, in addition to the secretion of angiogenic factors VEGF and b-FGF by B-CLL and MM cells, MM cells (but not B-CLL cells) induced a dramatic increase in expression of VEGFR-1 and VEGFR-3 on human bone marrow endothelial cells (HBMEC). It would seem that this increase in VEGFR-3 occurred via the ERK and mTOR pathways, since their respective inhibitors U0126, LY294002 or rapamycin were responsible for a decrease of VEGFR-3. In response to MM cells-increased VEGF receptors on HBMEC, endothelial cell migration was enhanced in a wound artificially produced in a semi-confluent HBMEC culture, a phenomenon which was also down-regulated by the same inhibitors that reversed the increase in VEGF receptors. The present study suggests that, in addition to the classic angiogenic pathway, another mechanism related to an increased expression of VEGFRs on HBMEC might exist in malignant hematopoietic angiogenesis.

Anti-RhoA and anti-RhoC siRNAs inhibit the proliferation and invasiveness of MDA-MB-231 breast cancer cells in vitro and in vivo.

Overexpression of RhoA or RhoC in breast cancer indicates a poor prognosis, due to increased tumor cell proliferation and invasion and tumor-dependent angiogenesis. Until now, the strategy of blockage of the Rho-signaling pathway has used either GGTI or HMG-CoA reductase inhibitors, but they are not specific to RhoA or RhoC inhibition. In this study, a new approach with anti-RhoA and anti-RhoC siRNAs was used to inhibit specifically RhoA or RhoC synthesis. Two transfections of either RhoA or RhoC siRNA (8.5 nM) into MDA-MB-231 human breast cancer cells or HMEC-1 endothelial cells induced extensive degradation of the target mRNA and led to a dramatic decrease in synthesis of the corresponding protein. In vitro, these siRNAs inhibited cell proliferation and invasion more effectively than conventional blockers of Rho cell signaling. Finally, in a nude mouse model, intratumoral injections of anti-RhoA siRNA (100 microl at 85 nM) every 3 days for 20 days almost totally inhibited the growth and angiogenesis of xenografted MDA-MB-231 tumors. One may infer from these observations that specific inhibition of the Rho-signaling pathway with siRNAs represents a promising approach for the treatment of aggressive breast cancers.

[Lung scintigraphy with technetium 99m depreotide in the assessment of solitary pulmonary nodules]. / La gammagrafía con 99mTc-depreótida en la valoración del nódulo pulmonar solitario.

A solitary pulmonary nodule (SPN) is defined as a parenchymal lesion measuring less than 3 cm in diameter that is not associated with other lesions. Ninety percent of SPNs are discovered incidentally and most are benign. The management of radiographically indeterminate SPNs has not been established and invasive procedures must be undertaken in order to understand the nature of the nodule. We review our experience with the use of somatostatin receptor scintigraphy with technetium Tc99m depreotide in 10 patients with suspected malignant SPN. We discuss the limitations and applications of this technique in the evaluation of whether SPNs are benign or malignant for the purpose of identifying patients for biopsy. For this application, this technique can be considered an alternative to positron emission tomography using fluorine-18 fluordeoxyglucose.

Fenofibrate inhibits angiogenesis in vitro and in vivo.

Fenofibrate, a peroxisome proliferator-activated receptor (PPAR)-alpha activator, used as a normolipidemic agent, is thought to offer additional beneficial effects in atherosclerosis. Since angiogenesis is involved in plaque progression, hemorrhage, and instability, the main causes of ischemic events, this study was designed to evaluate the action of fenofibrate on angiogenesis. Our results show that fenofibrate (i) inhibits endothelial cell proliferation induced by angiogenic factors, followed at high concentrations by an increase in apoptosis, (ii) inhibits endothelial cell migration in a healing wound model, (iii) inhibits capillary tube formation in vitro, and (iv) inhibits angiogenesis in vivo. Concerning the mechanism of action, the inhibition of endothelial cell migration by fenofibrate can be explained by a disorganization of the actin cytoskeleton. At the molecular level, fenofibrate markedly decreased basic fibroblast growth factor-induced Akt activation and cyclooxygenase 2 gene expression. This inhibition of angiogenesis could participate in the beneficial effect of fenofibrate in atherosclerosis.

New insights into the actions of bisphosphonate zoledronic acid in breast cancer cells by dual RhoA-dependent and -independent effects.

Zoledronic acid (ZOL) is a nitrogen-containing bisphosphonate and its use in reducing osteoporosis and cancer-induced osteolysis is increasing. Recent findings indicated that ZOL has a direct effect on cancer cells. In this study, the effect of ZOL was examined on the aggressive MDA-MB-231 breast cancer cell line. ZOL induces an important inhibition of cell invasion at low concentrations (1 microM). This is not explained by modifications of proteases involved in cell invasiveness (matrix metalloproteinases and urokinase-type plasminogen activator), but by a disorganisation of actin cytoskeleton due to RhoA inhibition related to its defective prenylation as it was reversed by geranylgeraniol (GGOH) and mimicked by the Rho selective inhibitor C3 exoenzyme. In addition, ZOL inhibits the chemotactic effect induced by stromal cell-derived factor 1(SDF-1), a chemokine greatly involved in cancer metastasis to bone. This effect is related to both reduction of cell motility induced by RhoA inhibition and to a decreased expression of CXCR-4, the SDF-1 receptor. Finally, ZOL reduces Cox-2 expression and, consequently, the secretion of prostaglandins E2 (PGE2) in a RhoA-independent manner. This inhibition could contribute to bone protection in breast cancers because PGE2 stimulates osteoclast-mediated bone resorption. In summary, new insights in the mechanism of ZOL action on aggressive breast cancer cells are demonstrated and could explain its beneficial action in both the reduction of osteolysis and prevention of metastasis.

Cooperation between monocytes and breast cancer cells promotes factors involved in cancer aggressiveness.

In breast cancers, clinical symptoms of inflammation localised around the tumour at the time of diagnosis have been considered to have poor prognosis significance. In this study, the biological mechanisms responsible for the deleterious action of monocytes in cancer were investigated. The incubation of the breast-cancer-derived MDA-MB231 cells with monocytes resulted in an increase in factors involved in cell invasion (i.e. both cancer cells and monocytes-associated urokinase and Tissue Factor, and PAI-1 and MMP-9 secretion). Moreover, the functions of monocytes were also modified. Incubation of monocytes with MDA-MB231 cancer cells resulted in a downregulation in the secretion of the antiproliferative cytokine Oncostatin M, while the apoptotic factor TNF alpha was dramatically increased. However, MDA-MB231 cancer cells have been shown to be resistant towards the apoptotic action of TNF alpha. These findings demonstrate that incubation of MDA-MB231 cancer cells with monocytes induced a crosstalk, which resulted in an increased expression of factors involved in cancer cell invasiveness and in a modification of monocytes function against cancer cells, while inflammatory effects were increased.

[Thalidomide inhibits the angiogenic activity of culture supernatants of multiple myeloma cell line].

OBJECTIVE: To investigate the pro-angiogenic effects of several multiple myeloma (MM) cell line culture supernatants on human bone marrow endothelial cell (HBMEC) proliferation, migration, and capillary formation, and the anti-angiogenic effects of thalidomide. METHODS: HBMEC was cultured in the presence of MM cell lines (IM9, XG1, U266 and MOLP-5) supernatants. Proliferation and migration of HBMEC were determined, capillary-like tubule formation of HBMEC was examined in fibrin and Matrigel. The inhibiting effect of thalidomide was investigated by adding it into myeloma cell line culture supernatants. Vascular endothelial growth factor (VEGF) was measured by ELISA. RESULTS: (1) MM cell lines culture supernatants promoted HBMEC proliferation and migration. (2) In fibrin and Matrigel, capillary-like tubule network formation promoted by the supernatants. (3) All of these effects could be inhibited by thalidomide. (4) This effect was not related to VEGF in the supernatants. CONCLUSIONS: MM cell line promote proliferation, migration and tubule formation by secreting VEGF or other several cytokines. Thalidomide can inhibit these effects.

Apigenin--strong cytostatic and anti-angiogenic action in vitro contrasted by lack of efficacy in vivo.

The cancer chemopreventive agent apigenin also has strong cytostatic and anti-angiogenic effects in vitro. We now investigated its efficacy against experimental Lewis lung carcinomas (LLC), C-6 gliomas and DHDK 12 colonic cancers in vivo. Tumour bearing mice received 50 mg/kg/day apigenin in three different galenical formulations during 12 days in 8-hourly intervals. Only weak effects of apigenin on the size and the number of new tumour blood vessels of both established and newly transplanted tumours were recorded although the intratumoural necrosis was elevated (45 +/- 15% vs. 20 +/- 7% (control), p < 0.05%). These results contrast sharply with the high in vitro sensitivity of LLC, C-6, DHDK 12 and endothelial cells to apigenin where complete growth suppression occurs at concentrations beyond 30 g/ml. Possible causes are discussed.