Estrogen as a key regulator of energy homeostasis and metabolic health.

Over the last two decades, it has become evident that estrogens preserve the integrity of energy homeostasis at central and peripheral levels. Estrogen deficiency, such as that caused by menopause or ovariectomy, has been linked to obesity and metabolic disorders that can be resolved or reversed by estrogen therapy. 17ß-estradiol (E2), as the major estrogen in the body, primarily regulates energy balance via estrogen receptor alpha (ERα). At the central level, E2 plays its catabolic role predominantly by interacting with hypothalamic arcuate neurons and sending signals via ventromedial hypothalamic neurons to control brown adipose tissue-mediated thermogenesis. In peripheral tissues, several organs, particularly the liver, brown and white adipose tissues, and pancreatic ß cells, have attracted considerable attention. In this review, we focused on the current state of knowledge of "central and peripheral" estrogen signaling in regulating energy balance via "nuclear and extranuclear pathways" in both "females and males". In this context, according to an exploratory approach, we tried to determine the principal estrogen receptor subtype/isoform in each section, the importance of extranuclear-initiated estrogen signaling on metabolic functions, and how sex differences related to ER signaling affect the prevalence of some of the metabolic disorders. Moreover, we discussed the data from a third viewpoint, understanding the clinical significance of estrogen signaling in abnormal metabolic conditions such as obesity or being on a high-fat diet. Collectively, this review exposes novel and important research gaps in our current understanding of dysmetabolic diseases and can facilitate finding more effective treatment options for these disorders.

Monepantel antitumor activity is mediated through inhibition of major cell cycle and tumor growth signaling pathways.

In women, epithelial ovarian cancer is the leading cause of gynaecological malignancy-related deaths. Development of resistance to standard platinum and taxane based chemotherapy and recurrence of the disease necessitate development of novel drugs to halt disease progression. An established concept is to target molecular and signaling pathways that substantially contribute to development of drug resistance and disease progression. We have previously shown that, monepantel (MPL) a novel small molecule acetonitrile derivative is highly effective in suppressing growth, proliferation and colony formation of ovarian cancer cells. These effects are achieved through inhibition of the mTOR/p70S6K pathway in cancer cells. The present study was conducted to find in vivo corroboration and explore the effect of MPL om other growth stimulating putative signaling pathways. Here, female nude mice with subcutaneous OVCAR-3 xenografts were treated with 25 and 50 mg/kg doses of MPL administered (IP) three times weekly for 2 weeks. At the doses employed, MPL was modestly effective at suppressing tumor growth, but highly effective in inhibiting, mTOR, P70S6K and 4EBP1. There were also modest reductions in tumor cyclin D1 and retinoblastoma protein expression. Furthermore, it was found that MPL treatment causes down-regulation of IGF-1R, and c-MYC thus unveiling new dimensions to the growing antitumor actions of this potential anticancer drug. MPL treatment led to reduced tumor volume and weights without causing any detectable side effects. Coupled with the recent human safety data published on this molecule, expanded future trials are highly anticipated.

The role of ERα36 in cell type-specific functions of estrogen and cancer development.

Exploring the regulatory effects of estrogen on different body organs via its receptors is largely of interest. Recently, the expression, signaling and the clinical significance of ERα36, the newly identified isoform of ERα, mediating non-genomic signaling of estrogen, have been studied in a wide range of organs and tumors. ERα36 is expressed highly in the CNS and actively involved in neuroprotection. It is also suggested to be an important estrogen receptor involved in preserving bone in postmenopausal women. On the oncological side, although ERα36 has usually been considered to be an oncogenic molecule, results from some studies paradoxically imply its protective role in certain tumors. Collectively, it seems that ERα36 is highly involved in cell type-specific functions of estrogen through its MAPK/ERK signaling, which is dependent on ERα36 expression levels, ligand concentrations and disease stage. The response is also dependent on the levels of ERα66 and ERß. These factors influence the ERK kinetic and determine the ultimate mitogenic or antimitogenic signaling of estrogen, leading to cell survival or cell death. In this review, we summarize the recent organ-specific, cellular and molecular events and the mechanisms involved in estrogen effects mediated through the ERα36/ ERα66 with a particular focus on carcinomas where more clinical information has recently emerged.

Expression patterns of ERα66 and its novel variant isoform ERα36 in lactotroph pituitary adenomas and associations with clinicopathological characteristics.

PURPOSE: The regulatory effects of estradiol on pituitary homeostasis have been well documented. However, the expression patterns of ERα66 and ERα36 and their correlations with the clinical course of postoperative prolactinoma tumors remain unclear. METHODS: The expression of ERα36, ERα66, Ki67, p53, and CD31 were determined by immunohistochemistry in 62 prolactinoma patients. Snap-frozen tumors and normal pituitaries were also examined by western blotting for estrogen receptor detection. RESULTS: A broad expression of ERα36 was identified in normal pituitaries. The median scores of ERα36 and ERα66 expression were 8 and 6 in normal pituitaries and 4 and 0 in tumors, respectively. Four phenotypes of ERα36 and ERα66 expression were explored in tumors with regard to sex, invasiveness, dopamine resistance, and recurrence. Low ERα36 expression was associated with tumor invasion and increased Ki67. Low ERα66 expression was associated with tumor invasion, dopamine-agonist resistance, and enhanced tumor size. Multivariable logistic regression analysis showed that low ERα36 expression is an independent risk factor for invasiveness. The significant inverse association of ERα66 with invasiveness, dopamine resistance, and tumor size remained significant after adjustment for sex as a potential confounder. After controlling for sex, the low ERα66/low ERα36 phenotype was 6.24 times more prevalent in invasive tumors than in noninvasive tumors. Although the decreasing trend of CD31 expression from surrounding nontumoral lactotroph adenomas to tumors was similar to that of the estrogen receptors, a significant correlation was not observed here. CONCLUSION: The decreasing trends of ERα36 and ERα66 expression from normal pituitaries to tumors are associated with aggressive clinical behavior.

Prognostic significance of Ki67 expression in malignant peritoneal mesothelioma.

OBJECTIVES: Although Ki67 measurement by immunohistochemistry has been widely used as a prognostic index in cancers, it has not been reported in malignant peritoneal mesothelioma (MPM). Hence, this study examines the prognostic significance of Ki67 in MPM. METHODS: Specimens from 42 MPM patients were screened for Ki67 expression using immunohistochemistry. Ki67 expression was classified into 2 groups on the basis of expression (<25%=low; ≥25%=high) using standard methods. Using Kaplan-Meier survival analysis, the significance of Ki67 was assessed in different clinicopathologic categories. RESULTS: High expression of Ki67 (≥25% by immunohistochemical evaluation) was correlated with poor survival in the overall group (P=0.001); male sex (P=0.001); female sex (P=0.001); epithelioid tumors (P=0.001): male epithelioid (P=0.001), female epithelioid (P=0.003); peritoneal cancer index (PCI): PCI<20 (P=0.001), PCI≥20 (P=0.002); and age at diagnosis (AAD): AAD<60 years (P=0.001), AAD≥60 years (P=0.004). Independent of Ki67, male sex (P=0.007), sarcomatoid histology (P=0.001), PCI≥20 (P=0.013), and AAD≥60 years (P=0.004) correlated with poor survival. Multivariate analysis showed that only AAD≥60 years (P=0.049) and high Ki67 expression for all tumors (P=0.031), male sex (P=0.038), female sex (P=0.021), epithelioid tumors (P=0.044), and AAD<60 years (P=0.029) were statistically significant. CONCLUSIONS: Ki67 expression affects prognosis in MPM patients and helps to predict survival within the various clinicopathologic categories.

Minocycline attenuates hypoxia-inducible factor-1α expression correlated with modulation of p53 and AKT/mTOR/p70S6K/4E-BP1 pathway in ovarian cancer: in vitro and in vivo studies.

Hypoxia-inducible factor (HIF)-1α is the key cellular survival protein under hypoxia, and is associated with tumor progression and angiogenesis. We have recently shown the inhibitory effects of minocycline on ovarian tumor growth correlated with attenuation of vascular endothelial growth factor (VEGF) and herein report a companion laboratory study to test if these effects were the result of HIF-1α inhibition. In vitro, human ovarian carcinoma cell lines (A2780, OVCAR-3 and SKOV-3) were utilized to examine the effect of minocycline on HIF-1 and its upstream pathway components to elucidate the underlying mechanism of action of minocycline. Mice harboring OVCAR-3 xenografts were treated with minocycline to assess the in vivo efficacy of minocycline in the context of HIF-1. Minocycline negatively regulated HIF-1α protein levels in a concentration-dependent manner and induced its degradation by a mechanism that is independent of prolyl-hydroxylation. The inhibition of HIF-1α was found to be associated with up-regulation of endogenous p53, a tumor suppressor with confirmed role in HIF-1α degradation. Further studies demonstrated that the effect of minocycline was not restricted to proteasomal degradation and that it also caused down-regulation of HIF-1α translation by suppressing the AKT/mTOR/p70S6K/4E-BP1 signaling pathway. Minocycline treatment of mice bearing established ovarian tumors, led to suppression of HIF-1α accompanied by up-regulation of p53 protein levels and inactivation of AKT/mTOR/p70S6K/4E-BP1 pathway. These data reveal the therapeutic potential of minocycline in ovarian cancer as an agent that targets the pro-oncogenic factor HIF-1α through multiple mechanisms.

Albumin nanoparticles increase the anticancer efficacy of albendazole in ovarian cancer xenograft model.

BACKGROUND: The poor prognosis of patients with drug resistant ovarian cancer and the lack of targeted therapy have raised the need for alternative treatments. Albendazole (ABZ) is an anti-parasite compound capable of impairing microtubule formation. We hypothesized that ABZ could be repurposed as a potential anti-angiogenic drug due to its potent inhibition of vascular endothelial growth factor (VEGF) in ovarian cancer with ascites. However, the poor aqueous solubility of ABZ limits its potential for cancer therapy. In this study, we have assembled ABZ with bovine serum albumin into nanoparticles with a size range of 7-10 nm (BSA-ABZ) and 200-250 nm (Nab-ABZ). We further examined the anticancer effects of ABZ carrying nanoparticles in ovarian cancer cells, in both in vitro and in vivo models. RESULTS: Drug release studies demonstrated that about 93% of ABZ was released from BSA-ABZ 10 nm in comparison to 83% from Nab-ABZ 200 nm at pH 7.4 in 8 days. In vitro cell proliferation studies showed that the BSA-ABZ 10 nm exhibited the highest killing efficacy of ovarian cancer cells with surprisingly least toxicity to healthy ovarian epithelial cells. Confocal microscopy and fluorescence activated cell sorting analysis (FACS) revealed more efficient internalization of the BSA-ABZ 10 nm by cancer cells. For in vivo studies, we examined the tumor growth, ascites formation and the expression of VEGF and secreted protein acidic and rich in cysteine (SPARC) in tumor samples and only VEGF in plasma samples. The BSA-ABZ 10 nm reduced the tumor burden significantly (p < 0.02) at a much lower drug dose (10 µg/ml) compare to free drug. Both formulations were capable of suppressing the ascites volume significantly (p < 0.05) and reducing the number of ascites cells. The expression of VEGF and SPARC was also reduced, which indicates the underlying therapeutic mechanism of the ABZ. CONCLUSION: Our data suggest that the BSA-ABZ may hold promise for the treatment and control of progression of ovarian cancer with ascites. However further studies are required to examine the efficacy of both the formulations in aggressive models of recurrent ovarian cancer with respect to particle size and dosing parameters.

MUC1 as a potential target in anticancer therapies.

MUC1 is a glycoprotein that is overexpressed in tumor cells. In normal cells it forms a protective layer against microbes and toxic chemicals, besides providing lubrication on ductal surfaces. Oversecretion of MUC1 provide cancer cells with invasiveness, metastasis, and resistance to death induced by reactive oxygen species. MUC1 is made up of 2 heterodimers, MUC1-N and MUC1-C. MUC1-N is heavily glycosylated at 5 regions of the variable N-tandem repeats. MUC1-C is divisible into extracellular, intracellular, and cytoplasmic domain (MUC1-C/CD). The extracellular domain serves as a docking site for epidermal growth factor receptors and other receptor kinases; the transmembrane domain serves to relay messages from extracellular to MUC1-C/CD. The MUC1-C/CD has 5 phosphorylating sites that on interacting with the SH2 domain of specific proteins can stimulate tumor growth. Therapies targeting MUC1 consists of monoclonal antibodies (MAb), vaccines, or small molecules (aptamers). MAb therapies are mainly aimed at MUC1-N with little success, however, new generation of MAb are being developed for MUC1-C. Vaccines (peptide, carbohydrate, glycopeptide, DNA, and dendritic cell) have been developed that recognizes the aberrant glycosylated region of the variable N-tandem repeats in MUC1-N, whereas new generation vaccines are aimed at the cytoplasmic region of MUC1-C. Aptamers (peptides that resemble DNA, RNA) have been used for blocking the dimerization of CQC region and the 5 phosphorylating region of MUC1-C. In addition, aptamers have been used as cytotoxic drug carriers. However, none of the therapies for MUC1 are currently in clinical application, as they need further refinement and evaluation.

Anticancer properties of novel aminoacetonitrile derivative monepantel (ADD 1566) in pre-clinical models of human ovarian cancer.

Monepantel (MPL) is a new anthelmintic agent approved for the treatment of nematode infections in farm animals. As a nematicide, it acts through a nematode-specific nicotinic receptor subtype which explains its exceptional safety in rodents and mammals. In the present study, we evaluated its potential as an anticancer agent. In vitro treatment of epithelial ovarian cancer cells with MPL resulted in reduced cell viability, inhibition of cell proliferation and suppression of colony formation. Proliferation of human ovarian surface epithelial cells and other non-malignant cells were however minimally affected. MPL-induced inhibition was found to be independent of the acetylcholine nicotinic receptor (nAChR) indicating that, its target in cancer cells is probably different from that in nematodes. Analysis of MPL treated cells by flow cytometry revealed G1 phase cell cycle arrest. Accordingly, MPL treated cells expressed reduced levels of cyclins D1 and A whereas cyclin E2 expression was enhanced. Consistent with a G1 phase arrest, cellular levels of cyclin dependent kinases (CDKs) 2 and 4 were lower, whereas expression of CDK inhibitor p27(kip) was increased. In cells expressing the wild-type p53, MPL treatment led to increased p53 expression. In line with these results, MPL suppressed cellular thymidine incorporation thus impairing DNA synthesis and inducing cleavage of poly (ADP-ribose) polymerase (PARP-1). Combined these pre-clinical findings reveal for the first time the anticancer potential of monepantel.

Monepantel induces autophagy in human ovarian cancer cells through disruption of the mTOR/p70S6K signalling pathway.

We have recently shown that the novel anthelmintic drug monepantel (MPL) inhibits growth, proliferation and colony formation, arrests the cell cycle and induces cleavage of PARP-1 in ovarian cancer cell lines. Here we report on the mechanism behind the anticancer properties of MPL. The cytotoxic effect of MPL on ovarian cancer cells (OVCAR-3 and A2780) was investigated employing a panel of tests used for the detection of apoptosis and autophagy. Apoptosis and autophagy were defined by caspase activity, DNA-laddering, Annexin-V and acridine orange (AO) staining. Autophagy markers such as LC3B, SQSTM1/p62 and mammalian target of rapamycin (mTOR) pathway related proteins were assessed by western blotting and ELISA techniques. MPL did not activate caspases 3 or 8, nor did it alter the percentage of Annexin V positive stained cells. Failure to cause DNA laddering and the inability of z-VAD-fmk to block the MPL antiproliferative effects led to the ruling out of apoptosis as the mechanism behind MPL-induced cell death. On the other hand, accumulation of acidic vacuoles with distinct chromatin morphology and an increase in punctuate localization of green fluorescent protein-LC3B, and MPL-induced changes in the expression of SQSTM1/p62 were all indicative of MPL-induced autophagy. Consistent with this, we found inhibition of mTOR phosphorylation leading to suppression of the mTOR/p70S6K signalling pathway. Our findings provide the first evidence to show that MPL triggers autophagy through the deactivation of mTOR/p70S6K signalling pathway.

p70 Ribosomal protein S6 kinase (Rps6kb1): an update.

The Rps6kb1 gene encodes the 70 kDa ribosomal protein S6 kinase (p70S6K), which is a serine/threonine kinase regulated by phosphoinositide 3-kinase (PI3K)/mammalian target of rapamycin (mTOR) pathway. p70S6K plays a crucial role in controlling cell cycle, growth and survival. The PI3K/mTOR signalling pathway is one of the major mechanisms for controlling cell survival, proliferation and metabolism and is the central regulator of translation of some components of protein synthesis system. Upon activation, this kinase phosphorylates S6 protein of ribosomal subunit 40S resulting in selective translation of unique family of mRNAs that contain oligopyrimidine tract on 5' transcriptional site (5'TOP). 5'TOP mRNAs are coding the components of translational apparatus including ribosomal proteins and elongation factors. Due to the role of p70S6K in protein synthesis and also its involvement in a variety of human diseases ranging from diabetes and obesity to cancer, p70S6K is now being considered as a new therapeutic target for drug development. Furthermore, p70S6K acts as a biomarker for response to immunosuppressant as well as anticancer effects of inhibitors of the mTOR. Because of the narrow therapeutic index of mTOR inhibitors, drug monitoring is essential, and this is usually done by measuring blood drug levels, therapeutic response and drug-induced adverse effects. Recent studies have suggested that plasma p70S6K is a reliable index for the monitoring of patient response to mTOR inhibitors. Therefore, a better understanding of p70S6K and its role in various pathological conditions could enable the development of strategies to aid diagnosis, prognosis and treatment schedules.

Gene of the month: Interleukin 6 (IL-6).

The Interleukin 6 (IL-6) gene encodes the classic proinflammatory cytokine IL-6. It is also known as interferon-ß2 (IFN-ß2), B cell stimulatory factor-2 and hybridoma/plasmacytoma growth factor. IL-6 is a multifunctional cytokine with a central role in many physiological inflammatory and immunological processes. Due to its major role in initiation as well as resolving inflammation, deregulation of IL-6 is a mainstay of chronic inflammatory and autoimmune diseases. Additionally, IL-6 has been shown to be implicated in pathogenesis of many human malignancies. Thus, a better understanding of IL-6 and its role in various pathological conditions could enable the development of strategies to use it as a therapeutic target. This short review focuses on the structure, regulation and biological activities of IL-6. In addition we discuss the role of IL-6 in diseases with inflammatory background and cancer and also the therapeutic applications of anti-IL-6 agents.

Involvement of urokinase-type plasminogen activator system in cancer: an overview.

Currently, there are several studies supporting the role of urokinase-type plasminogen activator (uPA) system in cancer. The association of uPA to its receptor triggers the conversion of plasminogen into plasmin. This process is regulated by the uPA inhibitors (PAI-1 and PAI-2). Plasmin promotes degradation of basement membrane and extracellular matrix (ECM) components as well as activation of ECM latent matrix metalloproteases. Degradation and remodeling of the surrounding tissues is crucial in the early steps of tumor progression by facilitating expansion of the tumor mass, release of tumor growth factors, activation of cytokines as well as induction of tumor cell proliferation, migration, and invasion. Hence, many tumors showed a correlation between uPA system component levels and tumor aggressiveness and survival. Therefore, this review summarizes the structure of the uPA system, its contribution to cancer progression, and the clinical relevance of uPA family members in cancer diagnosis. In addition, the review evaluates the significance of uPA system in the development of cancer-targeted therapies.

Human Sprouty1 suppresses growth, migration, and invasion in human breast cancer cells.

Breast cancer is the most common cancer and the leading cause of cancer death in women worldwide. Expression of human Sprouty1 (hSpry1) gene is downregulated in most breast cancer patients, implicating it as an important tumor suppressor gene. So, we hypothesized that overexpression of hSpry1 gene may suppress breast cancer cell growth, migration, and invasion. Here, we demonstrate that in breast cancer cell lines, MDA-MB-231 and T47D, transfection-induced overexpression of hSpry1 reduced cell population, proliferation, and colony formation in vitro without affecting cell apoptosis. Adhesion molecules act as both positive and negative modulators of cellular migration and invasion. Here, we found that overexpression of hSpry1 enhances the initial establishment events in breast cancer cell adhesion to type IV collagen and vitronectin. Moreover, the overexpression of hSpry1 in the highly invasive MDA-MB-231 breast cancer cells causes a significant reduction in cellular migration and invasion through Matrigel membranes. In addition, we showed that hSpry1 overexpression prevents VEGF secretion. VEGF is essential for primary tumor growth, migration, and invasion. Thus, our study provides a novel mechanism of tumor suppression activity of hSpry1.

Effect of minocycline on pentylenetetrazol-induced chemical kindled seizures in mice.

Inflammation is one of the mechanisms involved in seizure induction. In this study, the effect of minocycline, an anti-inflammatory drug, was investigated on kindling acquisition. Chemical kindling was induced by injection of a subthreshold dose of pentylenetetrazol (PTZ; 37.5 mg/kg) in mice on every other day. Two groups of animals received minocycline (25 mg/kg) at 1 h before or 1 h after PTZ injection. Following the last PTZ injection, the changes in gene expression of TNF-α receptor, γ2 subunit of GABAA receptor and NR2A subunit of NMDA receptor were assessed in the hippocampus and piriform cortex. Injection of minocycline before PTZ increased the latency to stage 4 seizure, and decreased the duration of stages 4 and 5 seizure. It also prevented the increase in the mRNA of NR2A subunit of NMDA receptor in the hippocampus and removed the PTZ-induced increase in mRNA of γ2 subunit of GABAA receptor in piriform cortex of PTZ kindled mice. Minocycline also prevented the increase in TNF-α receptor gene expression in both hippocampus and piriform cortex. Injection of minocycline after PTZ had no significant effect on measured parameters. Therefore, it can be concluded that minocycline may exert an anticonvulsant effect through preventing the increase in GABAA and NMDA receptor subunits. These effects are accompanied by a reduction in an important inflammation index, TNF-α receptor.

Ki67-BCL2 index in prognosis of malignant peritoneal mesothelioma.

BACKGROUND: malignant peritoneal mesothelioma (MPM) is a rare peritoneal mesothelial neoplasm. Ki67 and BCL2 are established prognostic markers in several cancers. High Ki67 expression indicates tumour progression, whilst similar expression of BCL2 retards tumour replication. Traditionally, prognosis in MPM is gauged with a single biomarker assessed separately in a dichotomous manner. Here, we examine prognosis with dual biomarkers incorporated in a model to predict survival. MATERIALS AND METHODS: Forty two MPM archival patient tumours were screened for Ki67 and BCL2 by immunohistochemistry and evaluated using standard methods. Ki67 and BCL2 expression was incorporated into a prognostic model to develop Ki67-BCL2 index. Using this index, three hazard groups were identified (high, medium and low risk). Kaplan-Meier survival analysis was performed to assess the significance of these hazard groups in the various clinicopathological categories. RESULTS: In all clinicopathological categories, high risk group showed poor prognosis compared to low risk group (p = < 0.001). Compared to medium risk, high risk group carried poor prognosis in all tumours, females, epitheloid tumours, peritoneal cancer index (PCI) < 20, ≥ 20, age at diagnosis (AAD) < 60, and ≥ 60 years. Independent of the Ki67-BCL2 index, male, sarcomatoid, PCI ≥ 20 and AAD ≥ 60 were poor prognostic factors. High risk group was an independent poor prognostic factor in all tumours, males, females and age < 60 years. The distribution of high risk: low risk group in male and female was 3: 2 and 2: 3, respectively, indicating a gender difference. Comparing hazard ratios generated by Ki67-BCL2 index to that of either Ki67 or BCL2, as a single prognostic biomarker, there was a reduction of HR values. CONCLUSION: Ki67-BCL2 index seems to suggest a more sensitive method of predicting prognosis. However, the current model needs further evaluation in an independent large cohort sample.

MUC1 has prognostic significance in malignant peritoneal mesothelioma.

BACKGROUND: Overexpression of MUC1 predicts poor survival in most cancers. Routine immunohistochemical detection of MUC1 is performed for differential diagnosis in malignant peritoneal mesothelioma (MPM). However, the prognostic significance of MUC1 in MPM has not been determined. 
 METHOD: We investigated MUC1 expression and other prognostic factors in relation to survival in 42 patients (20 males and 22 females) for whom archival samples were available, using immunohistochemistry. MUC1 was expressed in 38/42 (90%) patients. Its prognostic significance was statistically analyzed using the Kaplan-Meier method.
 RESULTS: High expression of MUC1 (immunohistochemical score of 5-8), was correlated with poor survival in several categories: all subtypes of tumors (p=0.001), male gender (p=0.017), female gender (p=0.001), epitheloid tumors (p=0.001), epitheloid tumors in males (p=0.005), epitheloid tumors in females (p=0.003), and age at diagnosis (AAD) <60 years (p=0.001). Amongst the other clinicopathological variables, univariate analysis also showed that male gender (p=0.007), sarcomatoid histology (p=0.001), peritoneal cancer index (PCI) ≥20 (p=0.013) and AAD ≥60 (p=0.001), correlated with poor survival. Multivariate analysis showed that only AAD ≥60 (p=0.049) was an independent prognostic factor, and that high MUC1 expression significantly correlated with the following categories: all subtypes of tumors (p=0.001), male gender (p=0.002), female gender (p=0.031), epitheloid tumors (p=0.031), and AAD <60y (p=0.012).
 CONCLUSION: AAD and high MUC1 expression in the tumor are indicators of poor prognosis. MUC1 evaluation by immunohistochemistry may serve as a useful prognostic tool in MPM, but may need further confirmation in a larger patients' cohort.

Minocycline targets the NF-κB Nexus through suppression of TGF-ß1-TAK1-IκB signaling in ovarian cancer.

UNLABELLED: Substantial evidence supports the critical role of NF-κB in ovarian cancer. Minocycline, a tetracycline, has been shown to exhibit beneficial effects in this malignancy through regulation of a cohort of genes that overlap significantly with the NF-κB transcriptome. Here, it was examined whether or not the molecular mechanism could be attributed to modulation of NF-κB signaling using a combination of in vitro and in vivo models. Minocycline suppressed constitutive NF-κB activation in OVCAR-3 and SKOV-3 ovarian carcinoma cells and was correlated with attenuation of IκBα kinase (IKK) activation, IκBα phosphorylation and degradation, and p65 phosphorylation and nuclear translocation. The inhibition of IKK was found to be associated with suppression of TGF-ß-activated-kinase-1 (TAK1) activation and its dissociation from TAK1-binding-protein-1 (TAB1), an indispensable functional mediator between TGF-ß and TAK1. Further studies demonstrated that minocycline downregulated TGF-ß1 expression. Enforced TGF-ß1 expression induced NF-κB activity, and minocycline rescued this effect. Consistent with this finding, TGF-ß1 knockdown suppressed NF-κB activation and abrogated the inhibitory effect of minocycline on this transcription factor. These results suggest that the minocycline-induced suppression of NF-κB activity is mediated, in part, through inhibition of TGF-ß1. Furthermore, the influence of minocycline on NF-κB pathway activation was examined in female nude mice harboring intraperitoneal OVCAR-3 tumors. Both acute and chronic administration of minocycline led to suppression of p65 phosphorylation and nuclear translocation accompanied by downregulation of NF-κB activity and endogenous protein levels of its target gene products. These data reveal the therapeutic potential of minocycline as an agent targeting the pro-oncogenic TGF-ß-NF-κB axis in ovarian cancer. IMPLICATIONS: This preclinical study lends support to the notion that ovarian cancer management would benefit from administration of minocycline.

Does the expression of BCL2 have prognostic significance in malignant peritoneal mesothelioma?

UNLABELLED: Background Malignant peritoneal mesothelioma (MPM) is a rare neoplasm of the peritoneal membrane that is causally related to asbestos exposure. Survival after treatment is poor. Current therapy involving hyperthermic intraperitoneal chemotherapy has improved survival in selective patients. In the past, several prognostic factors have been identified in MPM patients and this has prompted the development of new therapies and patient management. Since BCL2, an antiapoptotic oncoprotein, is a favourable prognostic factor in breast cancer, we investigated to determine the significance of BCL2 in MPM. Materials and Methods Forty two archival patient tumour sections embedded in paraffin blocks were sectioned and subjected to immunohistochemistry to detect BCL2. The staining intensity and abundance was classified using standard procedures and classified into two groups (0-4 = low & 5-8 = high expression). The distribution of BCL2 groups was examined in the different clinicopathological categories to determine prognosis using Kaplan-Meier survival analysis. RESULTS: Univariate analysis revealed that in almost all clinicopathological categories, high BCL2 expression predisposed patients to a favourable prognosis. Independent of BCL2 expression, univariate analysis also showed that male gender, sarcomatoid histology, high PCI and age at diagnosis ≥ 60 years were associated poor prognosis. Multivariate analysis indicated that for all tumours, males and females, high BCL2 expression was associated with good prognosis. Further, independent of BCL2, age ≥ 60 years is an unfavourable prognostic factor. CONCLUSION: Expression of BCL2 may serve to distinguish prognosis within the individual clinicopathological categories. BCL2 is also an independent variable in all tumours, males and females, with high expression being associated with good prognosis.