Patterns of cyclin E, retinoblastoma protein, and p21Cip1/WAF1 immunostaining in the oncogenesis of papillary thyroid carcinoma.

PURPOSE: Uncontrolled cell proliferation, a hallmark of cancer, may result from an increased expression of cell cycle up-regulators, and/or from a reduced expression of cell cycle down-regulators. In the present study, we analyzed, by immunohistochemistry, the expression of a panel of three proteins: cyclin E and two cell cycle inhibitors, p21(Cip1/WAF1) and retinoblastoma protein (pRb) product, in different stages of papillary thyroid carcinomas (PTC). EXPERIMENTAL DESIGN: We investigated immunostaining patterns of the proteins in question in 51 resected PTC in pathologic stages, ranging from pT(1a) to pT(4), taking into consideration their relation to clinicohistopathologic factors. RESULTS: We observed a significant, progressive loss of expression of p21(Cip1/WAF1) with advancing tumor grade. The differences reached values of significance between pT(1a) [papillary thyroid microcarcinomas (PMC)] and pT(2) and between PMC and pT(4) stages of PTC. pRb presented a similar immunostaining pattern to that of p21(Cip1/WAF1) and the differences reached values of significance between pT(1a) and pT(2), and between PMC and pT(4) stages of PTC. The results of cyclin E immunostaining corresponded to our recently published result, and a negative correlation was observed between the immunostaining index of cyclin E and pRb. CONCLUSIONS: The results of the present study suggest that cyclin E expression and suppression of pRb and p21(Cip1/WAF1) may be characteristic patterns of immunostaining for PTC with a tendency to early metastasizing. If our results are confirmed in a larger study, the diagnostic panel, constructed of the antibodies against these proteins, may become a valuable tool in predicting the metastatic potential in PTC.     

Induction of p53 up-regulated modulator of apoptosis messenger RNA by chemotherapeutic treatment of locally advanced breast cancer.

PURPOSE: In biopsies of patients with locally advanced breast cancer, we investigated the in vivo changes of the gene expression pattern induced by chemotherapy to find genes that are potentially responsible for the efficacy of the drug. EXPERIMENTAL DESIGN: Early cellular responses to chemotherapy-induced damage, both in vivo and in vitro, were investigated by analyzing chemotherapy-induced changes in gene expression profiles. Core biopsies were taken from nine patients with locally advanced breast cancer, before and at 6 hours after initiation of doxorubicin-based chemotherapy. Both samples were cohybridized on the same microarray containing 18,000 cDNA spots. RESULTS: The analysis revealed marked differences in gene expression profile between treated and untreated samples. The gene which was most frequently found to be differentially expressed was p53 up-regulated modulator of apoptosis (PUMA). This gene was up-regulated in eight of nine patients with an average factor of 1.80 (range, 1.36-2.73). In vitro MCF-7 breast cancer cells exposed to clinically achievable doxorubicin concentrations for 6 hours revealed marked induction of PUMA mRNA, as well. CONCLUSIONS: This is the first report describing PUMA mRNA to be up-regulated as a response to chemotherapy in patients. Because PUMA is a known member of the family of BH3-only proapoptotic proteins, this finding suggests PUMA's potential importance for the response to anticancer drugs.     

Allogeneic hematopoietic cell transplantation in chemotherapy‐induced aplasia in children with high‐risk acute myeloid leukemia or myelodysplasia

Relapse remains the most common cause of treatment failure after hematopoietic cell transplantation for acute myeloid leukemia. Inability to achieve hematologic complete remission has been a barrier to transplant for patients with refractory disease. We describe six children with refractory myeloid disease undergoing transplant in chemotherapy‐induced aplasia, as a strategy to facilitate curative therapy in refractory patients. Clofarabine‐ or high‐dose cytarabine‐based chemotherapy regimens were used to achieve marrow aplasia, followed by reduced‐intensity conditioning and allogeneic transplant before hematologic recovery. Long‐term disease control was achieved in five, with one transplant‐related mortality, suggesting the feasibility of this approach.     

Ontogenetic influence on rat susceptibility to lindane seizure after pretreatment with phencyclidine

The aim of the study was to determine the effects of early postnatal PCP treatment on the sensitivity of pubertal and adult rats to lindane proepileptogenic effects. Rat pups were treated with NaCl (0.9%) or PCP (10 mg/kg) at postnatal days 2, 6, 9 and 12. One control (NaCl-35) and one experimental (PCP-35) group have received lindane (4 mg/kg) at postnatal day 35, while others received lindane at postnatal day 65 (NaCl-65 and PCP-65). One week prior to lindane treatment three gold-plated EEG electrodes were implanted. Pubertal rats had significantly shorter latency time. After lindane, a prompt increase in power spectral density seen in PCP-treated groups vs. control was evident earlier in PCP-65 rats. The theta waves were significantly increased in PCP-35 and alpha rhythm in PCP-65 rats, when compared with corresponding controls. Postnatal PCP treatment increases the synchronization of brain electrical activity, thus contributing to the increased susceptibility to lindane.     

Nogo‐B expression,in arterial intima,is impeded in the early stages of atherosclerosis in humans

Nogo‐B (Reticulon 4B) is considered to be a novel vascular marker, which may have a protective role in injury‐induced neointima formation and atherosclerosis. Nogo A/B is found to be crucial for monocyte/macrophage recruitment in acute inflammation and it is expressed in CD68 + macrophages. We hypothesize that macrophage infiltration in atherosclerosis is not dependent on Nogo‐B expression in arterial wall. We have assessed Nogo‐B expression and macrophage accumulation in the iliac arteries of healthy organ donors and organ donors with cardiovascular risk factors. Paraffin sections of 66 iliac arteries, from 44 deceased organ donors (17 women and 27 men), were studied. The healthy and cardiovascular risk (CVR) subgroups were created. With regard to staging of the atherosclerotic process, the thickness of arterial intima was measured in digitalized images of H+E stained tissue sections. Immunohistochemical reactions (Nogo‐B and CD68) were carried out in all arteries (66 samples). Western blotting (WB‐19 samples) and real‐time PCR (27 samples) were performed on selected arteries. Significantly higher Nogo‐B expression was demonstrated in the intima of the healthy subjects' subgroup, using immunohistochemistry. WB and real‐time PCR revealed a trend toward lower Nogo‐B expression in the adventitia of the CVR subgroup. Furthermore, the thickness of the intima was found to negatively correlate with the expression of Nogo‐B in the intima and media (r = ?0.32; p < 0.05; r = ?0.32; p < 0.05). Macrophage infiltrates were more prominent in intima of CVR subjects (0.65 vs 3.52 a.u.; p < 0.01). Macrophage density in intima increased with atherosclerosis progression (r = 0.37; p < 0.01). CD68 macrophages density in adventitia was lower in CVR arteries than in healthy arteries. The expression of Nogo‐B, in arterial intima, is impeded in the early stages of atherosclerosis. Accumulation of arterial intimal CD68 macrophages has been shown to progress; however, the overall macrophage density in the adventitia is reduced in arteries shown to have intimal thickening. Macrophage infiltration is not accompanied by Nogo‐B expression in atherosclerotic arteries.     

Magnetic resonance imaging accurately tracks kidney pathology and heterogeneity in the transition from acute kidney injury to chronic kidney disease

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Melatonin nephroprotective action in Zucker diabetic fatty rats involves its inhibitory effect on NADPH oxidase

Excessive activity of NADPH oxidase (Nox) is considered to be of importance for the progress of diabetic nephropathy. The aim of the study was to elucidate the effect of melatonin, known for its nephroprotective properties, on Nox activity under diabetic conditions. The experiments were performed on three groups of animals: (i) untreated lean (?/+) Zucker diabetic fatty (ZDF) rats; (ii) untreated obese diabetic (fa/fa) ZDF rats; and (iii) ZDF fa/fa rats treated with melatonin (20 mg/L) in drinking water. Urinary albumin excretion was measured weekly. After 4 wk of the treatment, the following parameters were determined in kidney cortex: Nox activity, expression of subunits of the enzyme, their phosphorylation and subcellular distribution. Histological studies were also performed. Compared to ?/+ controls, ZDF fa/fa rats exhibited increased renal Nox activity, augmented expression of Nox4 and p47^phox subunits, elevated level of p47^phox phosphorylation, and enlarged phospho‐p47^phox and p67^phox content in membrane. Melatonin administration to ZDF fa/fa rats resulted in the improvement of renal functions, as manifested by considerable attenuation of albuminuria and some amelioration of structural abnormalities. The treatment turned out to nearly normalize Nox activity, which was accompanied by considerably lowered expression and diminished membrane distribution of regulatory subunits, that is, phospho‐p47^phox and p67^phox. Thus, it is concluded that: (i) melatonin beneficial action against diabetic nephropathy involves attenuation of the excessive activity of Nox; and (ii) the mechanism of melatonin inhibitory effect on Nox is based on the mitigation of expression and membrane translocation of its regulatory subunits.     

Respiration phase‐locks to fast stimulus presentations: Implications for the interpretation of posterior midline “deactivations”

The posterior midline region (PMR)—considered a core of the default mode network—is deactivated during successful performance in different cognitive tasks. The extent of PMR‐deactivations is correlated with task‐demands and associated with successful performance in various cognitive domains. In the domain of episodic memory, functional MRI (fMRI) studies found that PMR‐deactivations reliably predict learning (successful encoding). Yet it is unclear what explains this relation. One intriguing possibility is that PMR‐deactivations are partially mediated by respiratory artifacts. There is evidence that the fMRI signal in PMR is particularly prone to respiratory artifacts, because of its large surrounding blood vessels. As respiratory fluctuations have been shown to track changes in attention, it is critical for the general interpretation of fMRI results to clarify the relation between respiratory fluctuations, cognitive performance, and fMRI signal. Here, we investigated this issue by measuring respiration during word encoding, together with a breath‐holding condition during fMRI‐scanning. Stimulus‐locked respiratory analyses showed that respiratory fluctuations predicted successful encoding via a respiratory phase‐locking mechanism. At the same time, the fMRI analyses showed that PMR‐deactivations associated with learning were reduced during breath‐holding and correlated with individual differences in the respiratory phase‐locking effect during normal breathing. A left frontal region—used as a control region—did not show these effects. These findings indicate that respiration is a critical factor in explaining the link between PMR‐deactivation and successful cognitive performance. Further research is necessary to demonstrate whether our findings are restricted to episodic memory encoding, or also extend to other cognitive domains. Hum Brain Mapp 35:4932–4943, 2014. © 2014