l-carvone decreases breast cancer cells adhesion, migration, and invasion by suppressing FAK activation

Breast cancer is one of the most common types of cancer in the world and current therapeutic strategies present severe drawbacks. l-carvone (CRV), a monoterpene found in Mentha spicata (spearmint), has been reported to have potent anti-inflammatory activity. Here, we examined the role of CRV in breast cancer cell adhesion, migration and invasion in vitro and how this component could suppress the growth of Ehrlich carcinoma-bearing mice. In vivo, treatment with CRV significantly decreased tumor growth, increased tumor necrosis area, and reduced the expression of VEGF and HIF-1α in Ehrlich carcinoma-bearing mice. Furthermore, the anticancer efficacy of CRV was similar to currently used chemotherapy (Methotrexate), and the combination of CRV with MTX potentiated the chemotherapy effects. Further mechanistic investigation in vitro revealed that CRV modulates the interaction of breast cancer cells with the extracellular matrix (ECM) by disrupting focal adhesion, which was shown by scanning electron microscopy (SEM) and immunofluorescence. Moreover, CRV caused a decrease in β₁-integrin expression and inhibited focal adhesion kinase (FAK) activation. FAK is one of the most important downstream activators of several metastatic processes, including MMP-2 mediated invasion and HIF-1α/VEGF angiogenesis stimulus, both of which were found to be reduced in MDA-MB-231 cells exposed to CRV. Our results provide new insight about targeting β₁-integrin/FAK signaling pathway with CRV, which could be a new potential agent in the treatment of breast cancer.

Quantification of Tumor Cell Adhesion in Lymph Node Cryosections

Tumor-draining lymph nodes (LNs) are not merely filters of tumor-produced waste. They are one of the most common regional sites of provisional residence of disseminated tumor cells in patients with different types of cancer. The detection of these LN-residing tumor cells is an important biomarker associated with poor prognosis and adjuvant therapy decisions. Recent mouse models have indicated that LN-residing tumor cells could be a substantial source of malignant cells for distant metastases. The ability to quantify the adhesivity of tumor cells to LN parenchyma is a critical gauge in experimental research that focuses on the identification of genes or signaling pathways relevant for lymphatic/metastatic dissemination. Because LNs are complex 3D structures with a variety of appearances and compositions in tissue sections depending on the plane of section, their matrices are difficult to replicate experimentally in vitro in a fully controlled way. Here, we describe a simple and inexpensive method that allows the quantification of adhesive tumor cells to LN cryosections. Using serial sections of the same LN, we adapt the classic method developed by Brodt to use nonradioactive labels and directly count the number of adhering tumor cells per LN surface area. LN-adherent tumor cells are readily identified by light microscopy and confirmed by a fluorescence-based method, giving an adhesion index that reveals the cell-binding affinity to LN parenchyma, which is suggestive evidence of molecular alterations in the affinity binding of integrins to their correlate LN-ligands.

Beyond the Proteolytic Activity: Examining the Functional Relevance of the Ancillary Domains Using Tri-Dimensional (3D) Spheroid Invasion Assay

In this chapter, we describe a straightforward protocol to generate multicellular tumor spheroids (MTSs) and evaluate the role of specific genes in regulating cell invasiveness in real-time and tridimensional (3D) matrices. This approach provides advantages over other conventional invasion assays by offering intimate cell-cell and cell-ECM contacts and by mimicking the pathophysiological characteristics observed in tumor microenvironments (e.g., microregional gradients in glucose and O₂ concentrations and metabolic and proliferative tumor heterogeneity). We also provide an original and semiautomated approach to quantify MTS invasion using the freely available ImageJ software and plugins.

Intratumoral heterogeneity of ADAM23 promotes tumor growth and metastasis through LGI4 and nitric oxide signals

Intratumoral heterogeneity (ITH) represents an obstacle for cancer diagnosis and treatment, but little is known about its functional role in cancer progression. The A Desintegrin And Metalloproteinase 23 (ADAM23) gene is epigenetically silenced in different types of tumors, and silencing is often associated with advanced disease and metastasis. Here, we show that invasive breast tumors exhibit significant ADAM23-ITH and that this heterogeneity is critical for tumor growth and metastasis. We demonstrate that while loss of ADAM23 expression enhances invasion, it causes a severe proliferative deficiency and is not itself sufficient to trigger metastasis. Rather, we observed that, in ADAM23-heterotypic environments, ADAM23-negative cells promote tumor growth and metastasis by enhancing the proliferation and invasion of adjacent A23-positive cells through the production of LGI4 (Leucine-rich Glioma Inactivated 4) and nitric oxide (NO). Ablation of LGI4 and NO in A23-negative cells significantly attenuates A23-positive cell proliferation and invasion. Our work denotes a driving role of ADAM23-ITH during disease progression, shifting the malignant phenotype from the cellular to the tissue level. Our findings also provide insights for therapeutic intervention, enforcing the need to ascertain ITH to improve cancer diagnosis and therapy.

Auxiliary device for calibration of roller pumps: development and experimental results

INTRODUCTION

Roller pumps are commonly used in surgeries involving extracorporeal circulation and its regulation may influence the hemolysis rate.

OBJECTIVE

To describe an auxiliary device for adjusting roller pumps using the dynamic calibration method and show preliminary results of its application in surgical procedures.

METHOD

The device was tested in the laboratory environment with three disposable pressure transducers normally used in surgeries. In the operation room, tests were carried out with two groups of patients. Free hemoglobin plasma rates were measured, 5 minutes after perfusion started and immediately before the passage of the residual volume of the pump. For Group 1 (n = 22), occlusion measurements were carried out using the drop rate method and for Group 2 (n = 18), measurements were carried out using the auxiliary device and 300 mmHg calibration (mean pressure for the dynamic calibration method).

RESULTS

The auxiliary calibration device has shown calibration results statistically equal to those obtained with a reference device in the laboratory environment. We have found less variability of hemolysis rates in the operating room, using the auxiliary device and we did not observe any influence of unbalanced rollers in the hemolysis rates.

Genotoxic effects of aluminum, iron and manganese in human cells and experimental systems: A review of the literature

There is considerable evidence indicating an increase in neurodegenerative disorders in industrialized countries. The clinical symptoms and the possible mutagenic effects produced by acute poisoning and by chronic exposure to metals are of major interest. This study is a review of the data found concerning the genotoxic potential of three metals: aluminum (Al), iron (Fe) and manganese (Mn), with emphasis on their action on human cells.

Loss and sprouting of nitric oxide synthase neurons in the human epileptic hippocampus

PURPOSE

Nitric oxide (NO) has been implicated in a variety of functions, including the control of synaptic plasticity and sensory signaling. Current evidence suggests that this unconventional neurotransmitter mediates N-methyl-d-aspartate (NMDA) receptor-linked excitotoxicity. This study describes the expression of neuronal NO synthase (nNOS) immunoreactivity (IR) in hippocampi from patients with temporal lobe epilepsy (TLE).

METHODS

Hippocampi from patients with clinical symptoms, neuroimaging, and EEG typical of hippocampal sclerosis (HS; n = 22) were compared with those from patients with neocortical temporal lesions (NONHS; n = 4) and autopsy (AUT; n = 18) patients for total cells, and nNOS-IR neuron and puncta densities.

RESULTS

Compared with AUT, HS hippocampi had significantly less nNOS-IR neuron densities in the fascia dentata (FD); hilus, and CA4, CA3, CA2, and CA1 subfields. HS hippocampi had significantly greater nNOS-IR puncta densities in the FD, as compared with AUT and NONHS.

CONCLUSIONS

Our results show that hippocampi from TLE patients exhibit a loss of nNOS-IR neurons and an abnormal FD innervation. The release of NO can influence the dynamics of ionic channels and neurotransmitter release, thus affecting neuronal membrane potential. Because the NOergic transmission does not obey the topographic constraints imposed on conventional transmitters, target cells can be stimulated even in regions with severe deafferentation. The plastic changes described here may contribute to abnormal hippocampal excitability.

Fetal alcohol exposure alters neurosteroid modulation of hippocampal N-methyl-D-aspartate receptors

The actions of ethanol on brain ligand-gated ion channels have important roles in the pathophysiology of alcohol-related neurodevelopmental disorders and fetal alcohol syndrome. Studies have shown that N-methyl-d-aspartate (NMDA) receptors are among the ligand-gated ion channels affected by prenatal ethanol exposure. We exposed pregnant dams to an ethanol-containing liquid diet that results in blood ethanol levels near the legal intoxication limit in most states (0.08%). Primary cultures of hippocampal neurons were prepared from the neonatal offspring of these dams, and NMDA receptor function was assessed by patch clamp electrophysiological techniques after 6-7 days in culture in ethanol-free media. Unexpectedly, we did not detect any changes in hippocampal NMDA receptor function at either the whole-cell or single-channel levels. However, we determined that fetal alcohol exposure alters the actions of the neurosteroids pregnenolone sulfate and pregnenolone hemisuccinate, which potentiate NMDA receptor function. Western immunoblot analyses demonstrated that this alteration is not due to a change in the expression levels of NMDA receptor subunits. Importantly, in utero ethanol exposure did not affect the actions of neurosteroids that inhibit NMDA receptor function. Moreover, the actions of pregnenolone sulfate on type A gamma-aminobutyric acid and non-NMDA receptor function were unaltered by ethanol exposure in utero, which suggests that the alteration is specific to NMDA receptors. These findings are significant because they provide, at least in part, a plausible mechanistic explanation for the alterations in the behavioral responses to neurosteroids found in neonatal rats prenatally exposed to ethanol and to other forms of maternal stress (Zimmerberg, B., and McDonald, B. C. (1996) Pharmacol. Biochem. Behav. 55, 541-547).

Role of ERK/MAP kinase in mitogenic interaction between ACTH and FGF2 in mouse Y1 adrenocortical tumor cells

In G0/G1 cell cycle-arrested Y1 adrenocortical cells FGF2 is a strong mitogen, whereas ACTH39 can be a weak mitogen or a strong anti-mitogenic agent. Phosphorylated ERK1/2-MAP kinases are undetectable by Western and immunocitochemistry assay in G0/G1-arrested Y1 adrenal cells. Cell entry into S phase linearly correlates with migration of phosphorylated ERK to nucleus. FGF2 rapid and strongly triggers transient phosphorylation of ERK1/2, whereas ACTH39 is a poor ERK1/2 activator. But, the MEK1 inhibitor, PD98059 (50microM), inhibits cFos and cyclin D1 induction and DNA synthesis stimulation by both ACTH39 and FGF2, suggesting that ERK1/2 activation mediates the strong and the weak mitogenic effect of, respectively, FGF2 and ACTH39. In addition, ACTH39 antagonizes the FGF2 mitogenic effect keeping untouched ERK1/2 activation, c-Fos and cyclin D1 induction.

A review of the effects of prenatal or early postnatal ethanol exposure on brain ligand-gated ion channels

BACKGROUND

Ligand-gated ion channels mediate fast excitatory and inhibitory synaptic transmission in the developing central nervous system. These channels have been shown to have roles in neuronal proliferation, differentiation, and programmed cell death. Numerous studies over the past 10 years indicate that prenatal and/or early postnatal ethanol exposure affects neurotransmitter-gated ion channels.

METHODS

We conducted a review of the relevant literature, identified by a computer-assisted literature search. This review presents an overview of studies performed with experimental preparations from the brains of rodents exposed to ethanol in utero and/or during the neonatal period and summarizes some of the salient issues that have developed in the course of these investigations. Differences in ethanol exposure paradigms and blood alcohol concentrations obtained in these studies are highlighted, and directions for future research are suggested.

RESULTS

Most studies have focused on the effects of prenatal or early postnatal ethanol exposure on NMDA receptors. These studies show that ethanol exposure affects ligand binding, subunit expression, and function of this receptor. Fewer studies have examined ethanol's effects on ligand-gated ion channels other than NMDA receptors. For instance, a study reported changes in ligand binding to hippocampal kainate receptors. Another study found alterations in modulation of GABA(A) receptors by benzodiazepines and neurosteroids.

CONCLUSIONS

These studies suggest that the effects of ethanol on brain ion channels may have a role in the pathophysiology of Alcohol-Related Neurodevelopmental Disorders and Fetal Alcohol Syndrome.

Ultrasonic pulsed Doppler blood flowmeter for use in extracorporeal circulation

In cardiac surgeries, it is frequently necessary to make the external blood circulation and oxygenation artificially. This procedure is called extracorporeal circulation (EC) or heart-lung bypass. During EC, one of the most important parameters, which demands continuous monitoring, is the blood flow. In many cases, the blood flow is estimated by the pump velocity (in roller pumps) or measured with transducers based on electromagnetic methods (in centrifugal pumps). This article presents an ultrasonic Doppler blood flowmeter to be used in the arterial line of an extracorporeal circulation system. The ultrasonic probe is coupled to a half-inch tube connector of the extracorporeal arterial line, is not disposable, and does not need sterilization. The developed flowmeter revealed itself to be efficient and reliable and can be inserted in a closed-loop pump controller system or be used as stand-alone equipment.

Acute effects of ethanol on kainate receptors in cultured hippocampal neurons

BACKGROUND

Kainate receptors are a subclass of ionotropic glutamate receptors that regulate excitability and mediate synaptic transmission and plasticity in the hippocampus. The acute effects of ethanol on these receptors are not completely understood.

METHODS

The acute effects of ethanol on pharmacologically isolated kainate receptor-mediated currents were studied in cultured hippocampal neurons obtained from neonatal rats. Whole-cell patch-clamp electrophysiological techniques were used for these studies. LY303070 (GYKI-53784), a potent AMPA (alpha-amino-3-hydroxy-5-methylisoxazole-4-propionic acid) receptor-selective noncompetitive antagonist, was used to isolate kainate currents.

RESULTS

Kainate receptor-mediated currents corresponded to 7% of the total non-N-methyl-D-aspartate (non-NMDA) currents in these neurons and were reduced to 24% of control values in the presence of 15 microM lanthanum. These kainate receptor-mediated currents were significantly inhibited by ethanol concentrations of 50 mM or more. Under our recording conditions, ethanol inhibited non-NMDA receptor- and NMDA receptor-mediated currents to a similar extent as kainate receptor-mediated currents. Western blot analysis indicated that glutamate receptor-5 and -6/7 subunits, and kainic acid-2 subunits are expressed in these cultured hippocampal neurons.

CONCLUSIONS

The present results suggest that kainate receptors are important targets for the actions of ethanol in the central nervous system.

Histochemical characterization of NADPH-diaphorase activity in area 17 of diurnal and nocturnal primates and rodents

NADPH-diaphorase (NADPH-d) activity was studied comparatively in area 17 of four mammalian species, two primates and two rodents. Three brain hemispheres each from adult capuchin-monkeys, owl-monkeys, agoutis and guinea pigs were fixed with aldehyde fixatives by perfusion and 200 microns sections were submitted to NADPH-d histochemistry, using the indirect malic enzyme method. In all species studied the neuropil pattern of enzymes activity presented a clear layered appearance. In primates, histochemical staining was most intense in layer IVc, while in rodents the highest intensity of the neuropil reaction was in supragranular layers (II and III). Comparison of cell density in grey and white matter showed that the majority of NADPH-d-positive neurones were located in the white matter of primates but not of rodents. Since NADPH-d is a nitric oxide synthase the results are very important for comparative functional studies of neuromediators and their correlations with laminar and modular organization of area 17 of the mammalian brain.

Reflections on tissue characterisation

Theoretical predictions that absorption and velocity dispersion, in addition to characteristic acoustic impedance mismatch, mediate the reflectivity of a planar interface are explored. A technique to measure the frequency dependence of the reflectivity is described: a special hydrophone, purpose-built to this end, is utilised in order to show that perspex/water and neoprene/water reflectivities are not inconsistent with the general predictions of the theory. An approach towards displaying, simultaneously, both the temporal and spectral properties of ultrasound pulses is described, and its potential utility in both reflectivity measurement and investigation of non-linear propagation is proposed.