A major family of polyadenylylated cytoplasmic transcripts are expressed from the BamHI A-I region ofthe Epstein-Barr virus genome, off the strand complementary to that encoding several functions associated with viral replication and the lytic cycle, including the DNA polymerase (BALF-5). These complementary-strand transcripts (the main one is about 4.8 kilobases long), expressed in all cell types associated with Epstein-Barr virus, are present at high levels in nasopharyngeal carcinoma tumors. Sequence analysis of clones that correspond to spliced transcripts in a cDNA library from such a tumor, C15, generates a proffle of the main complementary mRNA. It contains at least three AUG-initiated open reading frames, the largest of which could be translated to give a polypeptide of about 20 kDa. Evidence from several types of experiments sg that conditions which support the up (or down) regulation of transcriptional expression from one viral DNA strand within the relevant region of the genome produce the opposite effect on transcripts from the other strand. The capacity for interference between complementary EpsteinBarr viral transcripts offers a mechanism for-control of gene expression that may be related to maintenance of viral latency.

Abstract. NEK2 [NIMA (never in mitosis gene A)-related expressed kinase 2] is associated with various biological behaviors in the development of cancer, while research concerning its association with drug resistance is limited. The association of NEK2 with drug resistance in ovarian cancer has not yet been reported. In the present study, on the basis of microarray results from Oncomine and the GEO Profiles online database, we revealed that NEK2 mRNA expression in ovarian cancer tissues is upregulated. In addition, its expression in drugresistant ovarian cancer cells was upregulated when compared with expression with their sensitive or parental counterparts. Finally, we performed a comprehensive bioinformatic analysis consisting of protein/gene-protein/gene interaction network, annotation of biological processes and microRNA-mRNA interaction analysis. We observed that NEK2 directly or indirectly interacts with a number of genes, proteins, microRNAs and biological processes associated with drug resistance in ovarian and other types of cancer. These results indicate that NEK2 contributes to drug resistance in ovarian cancer and it may be an important therapeutic target.

Background The purpose of the present investigation is to determine whether centrosome amplifications are present in breast tumor cells, whether there are differences of centrosome amplification between benign breast lesions and breast carcinomas, and whether centrosomal analysis can be of value in the diagnosis and prognosis of breast carcinoma.

Chronic consumption of a Western-type diet, containing both elevated sugar and fat, results in leptin resistance. We hypothesised that fructose, as part of the sugar component of Western-type diets, is one causative ingredient in the development of leptin resistance and that removal of this component will prevent leptin resistance despite high fat (HF) content. We fed rats a sugar-free (SF), 30 % HF (SF/HF) diet or a 40 % high-fructose (HFr), 30 % HF (HFr/HF) diet for 134 d. The HFr/HF diet resulted in impaired anorexic and body-weight responses to both peripherally (0·6 mg/kg, assessed on day 65 of the diet) and centrally (1·5 μg/d, assessed on days 129-134) administered leptin, whereas SF/HF-fed rats were fully leptin responsive. At day 70, half the HFr/HF-fed animals were switched to the SF/HF diet, reversing the leptin resistance (assessed 18 d after the diet switch). The HFr/HF diet elevated serum leptin and reduced adiponectin, and levels were restored abruptly at day 3 after switching to the SF/HF diet. These data demonstrate that a diet containing both HFr and fat leads to leptin resistance, while an isoenergetic SF/HF diet does not. Moreover, removal of fructose from this diet reverses the leptin resistance and the elevated leptin, suggesting a cause-and-effect relationship. These data suggest that fructose is the bioactive component of a HF/high-sugar diet that is essential for the induction of leptin resistance.

Angiotensin II (Ang II) type 1 receptor blocking drugs have been shown to inhibit the growth of prostate cancer cells and delay the development of prostate cancer. Functional Ang II type 2 receptors (AT2R) are present in these cells and inhibit growth induced by epidermal growth factor. The present studies report apoptosis of prostate cancer cells induced by AT2R overexpression. A recombinant adenoviral vector expressing AT2R (Ad-G-AT2R-EGFP) was transduced into prostate cancer cells, including androgen-independent (DU145 and PC3) and androgen-dependent cell lines (LNCaP). Following AT2R transduction, apoptosis was analyzed by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling staining and caspase-3 activity assays. The results indicate that increased expression of AT2R alone induced apoptosis in the prostate cancer lines, an effect that did not require Ang II. AT2R overexpression in DU145 cells induced inhibition of proliferation, a significant reduction of S-phase cells, and an enrichment of G 1 -phase cells. The data also indicate that overexpression of AT2R led to apoptosis via an extrinsic cell death signaling pathway that is dependent on activation of p38 mitogen-activated protein kinase, caspase-8, and caspase-3. Finally, the apoptosis induced by AT2R over-

To elucidate mechanisms of bone loss after spinal cord injury (SCI), we evaluated the time-course of cancellous and cortical bone microarchitectural deterioration via microcomputed tomography, measured histomorphometric and circulating bone turnover indices, and characterized the development of whole bone mechanical deficits in a clinically relevant experimental SCI model. 16-weeks-old male Sprague-Dawley rats received T laminectomy (SHAM, n = 50) or moderate-severe contusion SCI (n = 52). Outcomes were assessed at 2-weeks, 1-month, 2-months, and 3-months post-surgery. SCI produced immediate sublesional paralysis and persistent hindlimb locomotor impairment. Higher circulating tartrate-resistant acid phosphatase 5b (bone resorption marker) and lower osteoblast bone surface and histomorphometric cancellous bone formation indices were present in SCI animals at 2-weeks post-surgery, suggesting uncoupled cancellous bone turnover. Distal femoral and proximal tibial cancellous bone volume, trabecular thickness, and trabecular number were markedly lower after SCI, with the residual cancellous network exhibiting less trabecular connectivity. Periosteal bone formation indices were lower at 2-weeks and 1-month post-SCI, preceding femoral cortical bone loss and the development of bone mechanical deficits at the distal femur and femoral diaphysis. SCI animals also exhibited lower serum testosterone than SHAM, until 2-months post-surgery, and lower serum leptin throughout. Our moderate-severe contusion SCI model displayed rapid cancellous bone deterioration and more gradual cortical bone loss and development of whole bone mechanical deficits, which likely resulted from a temporal uncoupling of bone turnover, similar to the sequalae observed in the motor-complete SCI population. Low testosterone and/or leptin may contribute to the molecular mechanisms underlying bone deterioration after SCI.

Macrophage migration inhibitory factor (MIF) acts intracellularly to counteract the angiotensin (ANG) II type 1 receptor (AT1-R)-mediated chronotropic effect of ANG II in hypothalamic neurons, an effect mediated by the thiol-protein oxidoreductase (TPOR) activity of the MIF molecule. Here we determined the in vivo actions of MIF in regulating the physiological actions of ANG II that are mediated via the paraventricular nucleus (PVN), an area that serves as a relay point in the central nervous system (CNS)-mediated effects of ANG II on cardiovascular functions and water intake. Intracerebroventricular (icv) injection of ANG II into normotensive rats selectively increased MIF protein levels in the PVN and produced significant pressor and drinking responses that were inhibited by PVN administration of the AT1-R antagonist losartan. Overexpression of MIF in PVN neurons via Ad-Syn-MIF gene transfer attenuated the pressor and drinking responses produced by icv-injected ANG II. Consistently, intracellular application of MIF or MIF-(50-65) (which harbors the TPOR activity of MIF) into PVN sympathetic regulatory neurons, blunted the electrophysiological actions of ANG II at these cells. These observations establish for the first time that MIF within the PVN, acting via TPOR, is an intracellular regulator of the central cardiovascular and dipsogenic effects of ANG II.

Macrophage migration inhibitory factor (MIF) expression is increased by angiotensin II (Ang II) within paraventricular nucleus (PVN) neurons of normotensive rats and acts via its intrinsic thiol protein oxidoreductase (TPOR) to counterregulate the central nervous system-mediated pressor action of Ang II. Considering that the PVN-mediated actions of Ang II are enhanced in spontaneously hypertensive rats (SHRs) and contribute to the development of hypertension in these animals, we investigated this MIF regulatory mechanism in SHRs. Here, we have demonstrated that Ang II failed to increase MIF protein expression in the PVN of SHRs. Furthermore, although basal levels of MIF protein and mRNA were similar in the PVN of SHRs and normotensive rats, immunostaining revealed that MIF was either absent from or diminished in PVN neurons of SHRs. AAV2-mediated increases in MIF expression within PVN neurons of young (8 wk old) SHRs produced a chronic attenuation of hypertension and cardiac hypertrophy. However, similar AAV2-mediated transduction of [C60S]-MIF, which lacks TPOR activity, did not alter the development of hypertension or cardiac hypertrophy in SHRs. Collectively, these findings suggest that a lack of MIF expression within PVN neurons contributes to the development of hypertension and cardiac hypertrophy in SHRs.