Evaluation of PSF1 as a prognostic biomarker for prostate cancer.

BACKGROUND: Partner of SLD5 1 (PSF1) is an evolutionarily conserved DNA replication factor. Previous studies have suggested that transcriptional activity of the PSF1 gene correlated with malignancy of cancer cells. The objective of the current study was to evaluate the relationship between PSF1 expression and the clinical features of prostate cancer. METHODS: We determined the expression of PSF1 in 120 needle biopsy samples of prostate cancer by immunohistochemistry. We divided patients into PSF1-positive or -negative groups and analyzed the relationships between the expression of PSF1, the Gleason score, PSA level, TNM classification and prognosis. RESULTS: Our results showed that the PSF1 expression correlated significantly with PSA values at diagnosis (P=0.0028), with tumor grade (P<0.0001), and with clinical stage (P=0.0005). Moreover, the PSF1 expression correlated significantly with overall survival (hazard ratio (HR) 5.5; 95% confidence interval (CI) 2.17-15.8; P=0.003) and progression-free survival in 99 consecutive patients with prostate cancer. Noteworthy, the prognosis of PSF1-positive cases was also worse in patients with a Gleason score of 8-10 (HR 3.7; 95% CI 1.28-13.43; P=0.0143). Limitations include that this study had a retrospective design, that patients in the study were heterogeneous and included those with early and advanced cancer, and that small tumor fragments may not be representative of the entire carcinoma. CONCLUSIONS: PSF1 is expressed in high-grade prostate cancer and may be a useful biomarker to identify patients with a poor prognosis at the time of diagnosis.

The PERICLES research program: an integrated approach to characterize the combined effects of mixtures of pesticide residues to which the French population is exposed.

Due to the broad spectrum of pesticide usages, consumers are exposed to mixtures of residues, which may have combined effects on human health. The PERICLES research program aims to test the potential combined effects of pesticide mixtures, which are likely to occur through dietary exposure. The co-exposure of the French general population to 79 pesticide residues present in the diet was first assessed. A Bayesian nonparametric model was then applied to define the main mixtures to which the French general population is simultaneously and most heavily exposed. Seven mixtures made of two to six pesticides were identified from the exposure assessment. An in vitro approach was used for investigating the toxicological effects of these mixtures and their corresponding individual compounds, using a panel of cellular models, i.e. primary rat and human hepatocytes, liver, intestine, kidney, colon and brain human cell lines. A set of cell functions and corresponding end-points were monitored such as cytotoxicity, real-time cell impedance, genotoxicity, oxidative stress, apoptosis and PXR nuclear receptor transactivation. The mixtures were tested in equimolar concentrations. Among the seven mixtures, two appeared highly cytotoxic, five activated PXR and depending on the assay one or two were genotoxic. In some experiments, the mixture effect was quantitatively different from the effect expected from the addition concept. The PERICLES program shows that, for the most pesticides mixtures to which the French general population is exposed, the toxic effects observed on human cells cannot be easily predicted based on the toxic potential of each compound. Consequently, additional studies should be carried on in order to more accurately define the mixtures of chemicals to which the consumers are exposed, as well as to improve the investigation, prediction and monitoring of their potential human health effects.

microRNA-125b inhibits tube formation of blood vessels through translational suppression of VE-cadherin.

Angiogenesis is controlled positively or negatively by extrinsic and intrinsic molecular cues in endothelial cells (ECs); in the tumor microenvironment, the action of positive regulators exceeds that of negative regulators. Thus, overinduction of negative regulators may inhibit tumor angiogenesis. MicroRNAs (miRNAs or miRs) are endogenous short noncoding RNAs regulating gene expression either through translational inhibition or destabilization of target mRNA. Here, we show that miR-125b expression is transiently induced in ECs on stimulation with vascular endothelial growth factor or by ischemia. miR-125b inhibits translation of vascular endothelial (VE)-cadherin mRNA and in vitro tube formation by ECs. Injection of miR-125b into the tumor inhibited VE-cadherin expression by ECs and induced nonfunctional blood vessel formation, resulting in inhibition of tumor growth. It has been suggested that pro-angiogenic signals in ECs also upregulate anti-angiogenic molecules simultaneously via negative feedback. Because miR-125b induction in ECs is transient after pro-angiogenic stimulation, prolonged overexpression of miR-125b could result in blood vessel regression. Thus, miR-125b may be useful in cancer therapy by causing the collapse of the lumen of ECs.

[Metastatic lung tumor from colon cancer with cavitation: report of a case].

A 55-year-old man underwent rectal amputation for rectal cancer in August 2005. A tiny thin-walled cavity lesion in his left S1+2 was found on computed tomography (CT) of the chest in November 2008. The cavity lesion in the left S1+2 gradually increased in size over 3 months and positron emission tomography (PET) with 18F-fluorodeoxyglucose (FDG) showed FDG accumulation at the lesion. Videoassisted thoracoscopic (VATS) wedge resection was performed to make a definite diagnosis in March 2009. The pathological findings revealed a metastatic lung tumor from the rectal cancer. It is necessary to consider the possibility of metastatic lung tumors in a case with the cavity lesions especially in patients with a history of colon cancer.

The apelin/APJ system induces maturation of the tumor vasculature and improves the efficiency of immune therapy.

Immature and unstable tumor vasculature provides an aberrant tumor microenvironment and leads to resistance of tumors to conventional therapy. Hence, normalization of tumor vessels has been reported to improve the effect of immuno-, chemo- and radiation therapy. However, the humoral factors, which can effectively induce maturation of tumor vasculature, have not been elucidated. In this study, we found that the novel peptide apelin and its receptor APJ can induce the morphological and functional maturation of blood vessels in tumors. This apelin-induced tumor vascular maturation enhances the efficacy of cancer dendritic cell-based immunotherapy and significantly suppresses tumor growth by promoting the infiltration of invariant natural killer T cells into the central region of the tumor and thereby robustly inducing apoptosis of tumor cells. Additionally, we showed APJ expression to be enhanced in the tumor endothelium in comparison with normal-state endothelial cells. These findings provide a new target for tumor vascular-specific maturation, which is expected to improve the efficacy of conventional cancer therapies.

Role of intimate interactions between endothelial cells and the surrounding accessory cells in the maturation of blood vessels.

While blood vessels clearly have a fundamental role in supplying oxygen and nutrients, and transporting inflammatory cells throughout the body, they are also involved in organogenesis and maintenance. Blood vessels provide a niche that supports self-renewal of stem cell populations in normal organs. This role unfortunately also extends to the field of cancer biology; it has been suggested that cancer stem cells are located in perivascular regions supporting their proliferation. Through cell-to-cell interactions, arteries also have the important function of guiding appropriate migration of neurites. Therefore, analysis of the molecular mechanisms responsible for blood vessel formation and maintenance is important for developing strategies to regulate tissue regeneration. According to the usual concept of angiogenesis, it is widely accepted that homogeneous endothelial cells from preexisting vessels sprout and proliferate during angiogenesis. Recently, however, at least three different endothelial cell types designated tip, stalk and phalanx cells have been suggested to be involved in new blood vessel formation in sprouting angiogenesis. Given this endothelial cell heterogeneity, the involvement of a stem cell system in preexisting blood vessels is proposed. In addition, endothelial cells possess the capacity to differentiate into mesenchymal stem cells upon stimulation with growth factors, and pericytes show stem cell behaviour in their ability to differentiate into a variety of different histotypes. Moreover, under normal physiological conditions, haematopoietic stem cells differentiate into mural cells to provide blood vessel stability. These findings make it necessary to reconsider issues concerning the regulation of blood vessels by accessory cells situated around those vessels.

Changes in blood circulation of the contralateral Achilles tendon during and after acupuncture and heating.

The purpose of this study was to investigate the effects of acupuncture and heating (application of hot pack) treatments on blood circulation in the contralateral Achilles tendon. During the treatments (10 min for acupuncture, 20 min for heating) and recovery period (40 min), the blood volume (THb) and oxygen saturation (StO2) of the treated and the non-treated tendons were measured using red laser lights. During both treatments, THb and StO2 of the treated tendon increased significantly from the resting level. The increased THb and StO2 of the treated tendon were maintained until the end of the recovery period after removal of the acupuncture needle, although these values decreased after removal of the hot pack. Although THb of the non-treated sides did not change during both acupuncture and heating treatments, it increased gradually after removal of the acupuncture needle or the hot pack. For both treatments, the amount of increase in THb of the non-treated tendon was significantly correlated to that of the treated tendon during the last phase of recovery period. These results obtained from the healthy subjects imply that blood circulation in the injured tendon in a plaster cast may be improved by applying acupuncture or heating treatments to the contralateral healthy limb.

[Simultaneously treated thymoma and lung cancer; report of a case].

A 74-year-old man was admitted to our hospital in order to treat a mediastinal mass and 2 ground-glass attenuations in the right upper lobe detected by chest X-ray and computed tomography (CT). Partial resection of right lung and thymectomy were performed. The mediastinal mass and 2 ground-glass attenuations in the right upper lobe proved to be thymoma and bronchioloalveolar carcinomas, respectively by pathology.

Expression of angiogenic and neurotrophic factors in the progenitor cell niche of adult monkey subventricular zone.

The subventricular zone along the anterior horn (SVZa) of the cerebral lateral ventricle of adult mammals contains multipotent progenitor cells, which supposedly exist in an angiogenic niche. Numerous signals are known to modulate the precursor cell proliferation, migration or differentiation, in rodent models. In contrast, the data on signals regulating the primate SVZa precursors in vivo are scarce. We analyzed the expression at protein level of a panel of angiogenic and/or neurotrophic factors and their receptors in SVZa of adult macaque monkeys, under normal condition or after transient global ischemia which enhances endogenous progenitor cell proliferation. We found that fms-like tyrosine kinase 1 (Flt1), a receptor for vascular endothelial cell growth factor, was expressed by over 30% of the proliferating progenitors, and the number of Flt1-positive precursors was significantly increased by the ischemic insult. Smaller fractions of mitotic progenitors were positive for the neurotrophin receptor tropomyosin-related kinase (Trk) B or the hematopoietic receptor Kit, while immature neurons expressed Flt1 and the neurotrophin receptor TrkA. Further, SVZa astroglia, ependymal cells and blood vessels were positive for distinctive sets of ligands/receptors, which we characterized. The presented data provide a molecular phenotypic analysis of cell types comprising adult monkey SVZa, and suggest that a complex network of angiogenic/neurotrophic signals operating in an autocrine or paracrine manner may regulate SVZa neurogenesis in the adult primate brain.

Inhibitory effect of pain-eliciting transcutaneous electrical stimulation on vibration-induced finger flexion reflex in the human upper limb.

We studied the effects of non-pain transcutaneous electrical stimulation (TES) and pain-eliciting TES on vibration-induced finger flexion reflex (VFR) in 12 healthy volunteers. Tonic finger flexion reflex in the upper limb was induced by the application of vibratory stimulation on the volar side of the middle fingertip in the right hand before and after TES. Non-pain TES or pain-eliciting TES was applied on the skin between the bases of the first and second metacarpals in the right hand dorsal area in a crossover design. Pain-eliciting TES inhibited VFRs significantly (Fisher's PLSD, p <0.01), compared to those of the time-control group during and after TES. VFRs were reduced approximately to 63.8% and 78.6% of prestimulation flexion force during and after pain-eliciting TES, respectively. Nonpain TES did not inhibit VFR. These results suggest that pain-conducting afferent fibers have inhibitory neuronal connection over the ipsilateral reflex circuits of VFR in the upper limb.

Allelic imbalance and microsatellite instability in plasma DNA released from polyclonal pancreatic adenocarcinoma.

Evidence of circulating soluble DNA in blood-stream of cancer patients has emerged. Because the plasma DNA is largely derived from cancer cells, genetic analysis of plasma DNA is important to understand the molecular events occurred in cancer patient. Seven microsatellite markers in the soluble plasma DNA from patients with pancreatic adenocarcinoma and other pancreato-biliary malignant tumors were examined for microsatellite instability (MSI) and allelic imbalance (AI). A variety of genetic alterations including MSI and AI were detected in the plasma DNA. Some alterations were detected before recurrence of the tumor was verified. Analysis of five primary pancreatic adenocarcinomas by microdissection revealed that the heterogeneous nature of pancreatic tumors is associated with both MSI and AI in the same tumor. The presence of altered plasma DNA including MSI and/or AI from the same pancreatic cancer patient may be important evidence for the presence of these alterations in heterogeneous primary tumors. Analysis of plasma DNA could become one of the diagnostic or therapeutic measures for this type of pancreatic adenocarcinoma.

Role of hematopoietic stem cells in angiogenesis.

Angiogenesis is an important event for embryonic organogenesis as well as for tissue repair in the adult. Here we show that hematopoietic stem cells (HSCs) are essential for angiogenesis during embryogenesis. To investigate the role of HSCs in endothelial cell (EC) development, we analyzed AML1-deficient embryos, which lack definitive hematopoiesis. These embryos showed defective angiogenesis in the head, pericardium, and fetal liver. Para-aortic splanchnopleural (P-Sp) explant cultures on stromal cells (P-Sp cultures) did not generate definitive hematopoietic cells and showed defective angiogenesis in the AML1-null embryo. Disrupted angiogenesis in P-Sp cultures from AML1-null embryos was rescued by addition of HSCs. HSCsspecifically produce angiopoietin-1 (Ang1). Thus HSCs,which expressAng1, directly promoted migration of ECs. These findings suggest that HSCs alone prepare the hematopoietic microenvironment.

Expression of angiopoietin-2 in human glioma cells and its role for angiogenesis.

In highly vascular malignant glioma, glioma cells themselves may express angiogenic factors and induce angiogenesis. Recent studies have shown that novel angiogenic factors, angiopoietin-1 (Ang1) and -2 (Ang2), play important roles in the modulation of vasculogenesis and angiogenesis. In this study, we determined Ang2 mRNA expression in cultured human malignant glioma cells (U105, U251, and U373 MG) by reverse transcriptase-PCR. Western blot analysis and immunocytochemical analysis with antihuman Ang2 antibody revealed that Ang2 protein was expressed and secreted by these cells. Furthermore, hypoxia increased the Ang2 protein level in cultured glioma cells. Serial sections of 32 human glioma tissues (14 glioblastomas, eight anaplastic astrocytomas, seven astrocytomas, and three pilocytic astrocytomas) were immunostained against Ang2, vascular endothelial growth factor, Tie2, von Willebrand factor, and alpha smooth muscle actin. The immunoreactivity of each angiogenic factor was higher in malignant gliomas than in low-grade gliomas. Ang2 protein was detected not only in endothelial cells but also in glioma cells, and its expression was prominent in both the area surrounding the necrosis and the periphery of glioblastomas. In the area surrounding necrosis, Ang2 was highly expressed and tumor vessels showed regression. In the tumor periphery, Ang2 was highly expressed and many small vessels stained positively for von Willebrand factor but not for alpha smooth muscle actin, suggesting angiogenesis. Statistical analysis revealed that the Ang2 expression was negatively correlated with vessel maturation in malignant gliomas and that vascular endothelial growth factor expression was positively correlated with vessel maturation in low-grade gliomas (P < 0.05). These results suggest that glioma cells themselves express Ang2 and that expression may be induced by hypoxic stimulation and may play a crucial role in the vessel maturation, angiogenesis, and vessel regression in malignant glioma.

Stromal cells expressing ephrin-B2 promote the growth and sprouting of ephrin-B2(+) endothelial cells.

Ephrin-B2 is a transmembrane ligand that is specifically expressed on arterial endothelial cells (ECs) and surrounding cells and interacts with multiple EphB class receptors. Conversely, EphB4, a specific receptor for ephrin-B2, is expressed on venous ECs, and both ephrin-B2 and EphB4 play essential roles in vascular development. The bidirectional signals between EphB4 and ephrin-B2 are thought to be specific for the interaction between arteries and veins and to regulate cell mixing and the making of particular boundaries. However, the molecular mechanism during vasculogenesis and angiogenesis remains unclear. Manipulative functional studies were performed on these proteins in an endothelial cell system. Using in vitro stromal cells (OP9 cells) and a paraaortic splanchnopleura (P-Sp) coculture system, these studies found that the stromal cells expressing ephrin-B2 promoted vascular network formation and ephrin-B2(+) EC proliferation and that they also induced the recruitment and proliferation of alpha-smooth muscle actin (alpha-SMA)-positive cells. Stromal cells expressing EphB4 inhibited vascular network formation, ephrin-B2(+) EC proliferation, and alpha-SMA(+) cell recruitment and proliferation. Thus, these data suggest that ephrin-B2 and EphB4 mediate reciprocal interactions between arterial and venous ECs and surrounding cells to form each characteristic vessel. (Blood. 2001;98:1028-1037)

Successfully resected hepatoblastoma in a young adult with chronic hepatitis B: report of a case.

Hepatoblastoma usually occurs in children, but a few cases have also been reported in adults. We report the unusual case of hepatoblastoma in an 18-year-old adult with chronic hepatitis B. He visited a local hospital with right upper abdominal pain. Abdominal ultrasound showed a large mass in the right lobe of his liver. He was referred to our hospital and admitted for further examination. At admission, liver function tests gave slightly elevated results (aspartate aminotransferase (AST) 103 IU/l, alanine aminotransferase (ALT) 63 IU/l). A test for hepatitis virus revealed that he was a hepatitis B surface antigen (HBsAg) carrier and had experienced seroconversion. His alpha-fetoprotein (AFP) was elevated to 1 548 000 IU/ml. Abdominal ultrasound showed a 109 x 96 x 80-mm mass with mosaic pattern in the right lobe of the liver and right portal vein thrombus. Abdominal computed tomography (CT) demonstrated a large low-density mass occupying the right lobe, with some high-density parts that showed calcification. From these results, we diagnosed hepatoblastoma in a young adult. A right lobectomy was performed. Pathological examination showed a highly differentiated hepatoblastoma. Adjuvant chemotherapy was performed with cisplatin and pirarubicin. The patient has been well and free of recurrence for 12 months, and his AFP level remains almost normal.

Functional blockade of platelet-derived growth factor receptor-beta but not of receptor-alpha prevents vascular smooth muscle cell accumulation in fibrous cap lesions in apolipoprotein E-deficient mice.

BACKGROUND: The vascular smooth muscle cell (VSMC) is the central cell component involved in the fibroproliferative response in atherogenesis. As the lesion advances, VSMCs migrate from the media into the subendothelial space, thereby forming fibrous plaque lesions. Platelet-derived growth factor (PDGF) has been known to be a potent chemoattractant and mitogen for SMCs, but the pathophysiological role of the 2 PDGF receptors, receptor-alpha (PDGFR-alpha) and receptor-beta (PDGFR-beta) in atherogenesis is poorly understood. To clarify this problem, we prepared antagonistic rat monoclonal antibodies, APA5 and APB5, against murine PDGFR-alpha and PDGFR-beta, respectively. METHODS AND RESULTS: Apolipoprotein E-deficient mice were fed a high-fat diet containing 0.3% cholesterol from 6 weeks of age and subjected to injection with 1 mg/d IP of either antibody from 12 to 18 weeks every other day. In the mice injected with APB5, the aortic atherosclerotic lesion size and the number of intimal VSMCs were reduced by 67% and 80%, respectively, compared with the control mice injected with irrelevant rat IgG. In contrast, the mice that received APA5 showed only minimal reduction of lesion size, and a large number of VSMCs were observed in the intima. In the intima of advanced lesions, APB5 immunolabeled VSMCs, whereas APA5 could detect VSMCs mainly in the media. CONCLUSIONS: These results indicate that PDGFR-beta plays a significant role in formation of fibrous atherosclerotic lesions and that regulation of the signal transduction through PDGFR-beta could affect atherogenesis in mice.

[A case of recurrent gastric cancer successfully treated with TS-1].

A patient with recurrent gastric cancer which infiltrated the pelvic muscle after the treatment of paraaortic lymph node and ovarian metastases was successfully managed by a novel oral anticancer drug, TS-1. TS-1 was administered at a dose of 80 mg/day. One course consisted of two repetitions of consecutive administration of TS-1 for 14 days and withdrawal of TS-1 for 14 days. Adverse reactions were mild and the patient did not request hospitalization after two courses had been completed. Subjective symptoms such as difficulty in walking improved after one week and a partial response was obtained after 2 weeks of treatment. At the end of 4 courses we could remove an indwelling pyelocatheter for the ureter stricture. As of 14 months after the beginning of administration of TS-1, the patient is being treated as an outpatient and has attained a better QOL than before.