A unique protein kinase C-dependent pathway for tissue factor downregulation in pericytes.

Essentials Many mediators increase tissue factor (TF) expression in a wide variety of cell types. The only known example of TF downregulation is by pericytes during wound healing angiogenesis. Downregulation of TF mRNA and protein in cultured pericytes is Protein Kinase C (PKC) dependent. Pericyte TF regulation is unique, since PKC mediates increased TF in all other cell types tested. SUMMARY: Background Embryonic and tumor-associated angiogenesis are linked to elevated expression of the procoagulant transmembrane receptor tissue factor (TF). In contrast, we have reported that high baseline TF expression by perivascular cells (pericytes) is dramatically reduced during angiogenesis at sites of wound healing. This is the only setting in which active TF downregulation has been reported, thus revealing a novel mechanism of TF regulation. Objectives To define the mechanisms underlying the unique pattern of TF expression in pericytes. Methods TF expression in primary cultures of human pericytes is not altered by angiogenic cytokines or growth factors, but is actively downregulated by phorbol 12-myristate 13-acetate (PMA). We characterized TF transcription, protein stability and trafficking in response to PMA. Results Exposure to PMA reduced TF mRNA synthesis and shortened the half-life of TF protein from 11 h to 4.5 h. Addition of PMA rapidly triggered endocytosis of cell surface TF, followed by degradation in lysosomes. Cell surface TF coagulant activity was maintained until internal stores were depleted. Reduction of TF transcription, TF endocytosis and enhanced degradation of TF protein were all blocked by broad-spectrum inhibitors of protein kinase C (PKC). This was a surprising finding, because PKC activation increases TF expression in other cell types that have been tested. Conclusions The unique PKC-dependent pathway of TF downregulation in pericytes suggests that TF downregulation may play a functional role in angiogenesis. Distinct pathways regulating pathological and physiological TF expression could be utilized to modulate TF expression for therapeutic purposes.

Development of the Multiple Sclerosis Resiliency Scale (MSRS).

OBJECTIVES: While resilience has been an area of increasing research, there are no measures that are specific to the psychological, social, and physical factors associated with resilience in persons with multiple sclerosis (PwMS). This study aimed to develop the MS Resiliency Scale (MSRS), a multidimensional measure. Items were created based on a review of the literature, with five hypothesized subscales, and then evaluated in a large sample of PwMS. METHOD: Participants (N = 932) were primarily recruited through the North American Research Committee on MS (NARCOMS) and completed the study electronically. Principal components analysis was utilized to determine the number of factors and whether they aligned with the theorized model. RESULTS: Using an unforced solution with oblique (promax) rotation and Kaiser normalization, and suppressing items with coefficients below 0.4, 25 items were retained in five subscales that accounted for 42.75% of the variance: Emotional and Cognitive Strategies (13 items; α = .92), Physical Activity and Diet (3 items; α = .77), MS Peer Support (2 items; α = .82), Support from Family and Friends (5 items; α = .79), and Spirituality (2 items; α = .91). The total score was negatively correlated with depression, r = -.72, p < .001 and anxiety, r = -.56, p < .001. IMPLICATIONS: The 25-item MSRS assesses several psychological, social, and physical factors associated with resilience in PwMS, and may be a helpful tool in identifying individuals in need of additional assistance or support. (PsycINFO Database Record

Assessing the criterion validity of four highly abbreviated measures from the Minimal Assessment of Cognitive Function in Multiple Sclerosis (MACFIMS).

OBJECTIVE: Cognitive dysfunction is prevalent in multiple sclerosis. As self-reported cognitive functioning is unreliable, brief objective screening measures are needed. Utilizing widely used full-length neuropsychological tests, this study aimed to establish the criterion validity of highly abbreviated versions of the Brief Visuospatial Memory Test - Revised (BVMT-R), Symbol Digit Modalities Test (SDMT), Delis-Kaplan Executive Function System (D-KEFS) Sorting Test, and Controlled Oral Word Association Test (COWAT) in order to begin developing an MS-specific screening battery. METHOD: Participants from Holy Name Medical Center and the Kessler Foundation were administered one or more of these four measures. Using test-specific criterion to identify impairment at both -1.5 and -2.0 SD, receiver-operating-characteristic (ROC) analyses of BVMT-R Trial 1, Trial 2, and Trial 1 + 2 raw data (N = 286) were run to calculate the classification accuracy of the abbreviated version, as well as the sensitivity and specificity. The same methods were used for SDMT 30-s and 60-s (N = 321), D-KEFS Sorting Free Card Sort 1 (N = 120), and COWAT letters F and A (N = 298). RESULTS: Using these definitions of impairment, each analysis yielded high classification accuracy (89.3 to 94.3%). CONCLUSIONS: BVMT-R Trial 1, SDMT 30-s, D-KEFS Free Card Sort 1, and COWAT F possess good criterion validity in detecting impairment on their respective overall measure, capturing much of the same information as the full version. Along with the first two trials of the California Verbal Learning Test - Second Edition (CVLT-II), these five highly abbreviated measures may be used to develop a brief screening battery.

Psychological and physical predictors of illness intrusiveness in patients with multiple sclerosis.

Physical disability as well as psychological factors may contribute to illness intrusiveness. The aim of this study was to determine if level of disability, anxiety, and depression predicted illness intrusiveness in patients with multiple sclerosis (MS). A second aim of this study was to determine if anxiety and depression moderated the impact of disability on illness intrusiveness. MS (N=185) patients were recruited from a MS outpatient clinic that was part of a major medical center in New Jersey. Hierarchical linear regressions demonstrated that disability, anxiety, and depression each independently predicted illness intrusiveness. Anxiety and depression were not shown to moderate the impact of disability on illness intrusiveness. Implications of results from the first aim suggest that reducing psychological distress such as anxiety and depression may also reduce illness intrusiveness in patients with MS.

Thermal dose fractionation affects tumour physiological response.

PURPOSE: It is unknown whether a thermal dose should be administered using a few large fractions with higher temperatures or a larger number of fractions with lower temperatures. To evaluate this we assessed the effect of administering the same total thermal dose, approximately 30 CEM43T(90), in one versus three to four fractions per week, over 5 weeks. MATERIALS AND METHODS: Canine sarcomas were randomised to receive one of the hyperthermia fractionation schemes along with fractionated radiotherapy. Tumour response was based on changes in tumour volume, oxygenation, water diffusion quantified using MRI, and a panel of histological and immunohistochemical end points. RESULTS: There was a greater reduction in tumour volume and water diffusion at the end of therapy in tumours receiving one hyperthermia fraction per week. There was a weak but significant association between improved tumour oxygenation 24 h after the first hyperthermia treatment and extent of volume reduction at the end of therapy. Finally, the direction of change of HIF-1α and CA-IX immunoreactivity after the first hyperthermia fraction was similar and there was an inverse relationship between temperature and the direction of change of CA-IX. There were no significant changes in interstitial fluid pressure, VEGF, vWF, apoptosis or necrosis as a function of treatment group or temperature. CONCLUSIONS: We did not identify an advantage to a three to four per week hyperthermia prescription, and response data pointed to a one per week prescription being superior.

Comparison of genomics and functional imaging from canine sarcomas treated with thermoradiotherapy predicts therapeutic response and identifies combination therapeutics.

PURPOSE: While hyperthermia is an effective adjuvant treatment to radiotherapy, we do not completely understand the nature of the response heterogeneity. EXPERIMENTAL DESIGN: We performed gene expression analysis of 22 spontaneous canine sarcomas before and after the first hyperthermia treatment administered as an adjuvant to radiotherapy. In parallel, diffusion-weighted MRI (DWI) was done prior to the treatment course and at the end of therapy. RESULTS: From the integrative analysis of gene expression and DWI, we identified significant correlation between tumor responses with genes involved in VEGF signaling, telomerase, DNA repair, and inflammation. The treatment-induced changes in gene expression identified 2 distinct tumor subtypes with significant differences in their gene expression and treatment response, as defined by changes in DWI. The 2 tumor subtypes could also be readily identified by pretreatment gene expression. The tumor subtypes, with stronger expression response and DWI increase, had higher levels of HSP70, POT1, and centrosomal proteins, and lower levels of CD31, vWF, and transferrin. Such differential gene expression between the 2 subtypes was used to interrogate connectivity map and identify linkages to an HSP90 inhibitor, geldanamycin. We further validated the ability of geldanamycin to enhance cell killing of human tumor cells with hyperthermia and radiotherapy in clonogenic assays. CONCLUSIONS: To our knowledge, this is one of the first successful attempts to link changes in gene expression and functional imaging to understand the response heterogeneity and identify compounds enhancing thermoradiotherapy. This study also demonstrates the value of canine tumors to provide information generalizable to human tumors.

Feasibility of using gene expression analysis to study canine soft tissue sarcomas.

The prognosis given for canine soft tissue sarcomas (STSs) is based primarily on histopathologic grade. The decision to administer adjuvant chemotherapy is difficult since less than half of patients with high-grade STSs develop metastatic disease. We hypothesize that there is a gene signature that will improve our ability to predict development of metastatic disease in STS patients. The objective of this study was to determine the feasibility of using cDNA microarray and quantitative real-time PCR (qRT-PCR) analysis to determine gene expression patterns in metastatic versus nonmetastatic canine STSs, given the inherent heterogeneity of this group of tumors. Five STSs from dogs with metastatic disease were evaluated in comparison to eight STSs from dogs without metastasis. Tumor RNA was extracted, processed, and labeled for application to the Affymetrix Canine Genechip 2.0 Array. Array fluorescence was normalized using D-Chip software and data analysis was performed with JMP/Genomics. Differential gene expression was validated using qRT-PCR. Over 200 genes were differentially expressed at a false discovery rate of 5%. Differential gene expression was validated for five genes upregulated in metastatic tumors. Quantitative RT-PCR confirmed increased relative expression of all five genes of interest in the metastatic STSs. Our results demonstrate that microarray and qRT-PCR are feasible methods for comparing gene signatures in canine STSs. Further evaluation of the differences between gene expression in metastatic STSs and in nonmetastatic STSs is likely to identify genes that are important in the development of metastatic disease and improve our ability to prognosticate for individual patients.

A pilot study of predictive markers of chemotherapy-related amenorrhea among premenopausal women with early stage breast cancer.

BACKGROUND: Premenopausal women treated for early stage breast cancer (ESBC) are at risk for chemotherapy-related amenorrhea (CRA). Prospectively-validated, predictive markers of CRA are needed. PATIENTS AND METHODS: Premenopausal women with ESBC and planned chemotherapy (>/= 25% risk of amenorrhea) were evaluated. Follicle stimulating hormone (FSH), estradiol, Inhibin A and B, anti-Müllerian hormone (AMH), and quality of life (QOL) were prospectively evaluated pre-, post-, 6 months and 1 year post-chemotherapy and correlated with age and menstrual status. CRA was defined as absence of menses 1 year post-chemotherapy. RESULTS: Forty-four women were evaluated at the time of analysis. Median age at diagnosis and FSH 1 year post-chemotherapy were higher among women with CRA (44 yrs [33-51] vs. 40 yrs [31-43]; p = 0.03; 39.8 vs. 5.0 mLU/mL, p = 0.0058, respectively). Median estradiol 1 year post-chemotherapy was higher among women who resumed menses (108.3 vs. 41.3 pg/mL, p = 0.01). Pre-chemotherapy median Inhibin B and AMH were lower among women with CRA (33.2 vs. 108.8 pg/mL; p = 0.03; 0.16 vs. 1.09 ng/mL, p = 0.02, respectively). The risk of CRA was increased among women with lower pre-chemotherapy Inhibin B (RR = 1.67, p = 0.15) and AMH (RR = 1.83, p = 0.05). Amongst women whose pre-chemotherapy Inhibin B and AMH values were below the median, the incidence of CRA was 87.5%. CONCLUSIONS: RESULTS indicate that pre-chemotherapy Inhibin B and AMH are lower among women experiencing CRA and may be predictive of CRA among premenopausal women facing chemotherapy for ESBC.

The effect of darbepoetin alfa on growth, oxygenation and radioresponsiveness of a breast adenocarcinoma.

Tumor hypoxia is associated with poor clinical outcome in a variety of tumors, including cervical, head/neck and breast cancer. Administration of erythropoietic factors has been suggested as a means of improving tumor oxygenation (pO2). This study randomized rats to treatment with low-dose or high-dose darbepoetin alfa or a placebo to determine the effect of darbepoetin alfa on the pO2, growth and response to radiation therapy of R3230 mammary adenocarcinoma. Rats received 3 microg/kg (high dose) or 0.2 microg/kg (low dose) darbepoetin alfa or placebo for eight doses prior to either (1) pO2 measurement and pimonidazole staining or (2) irradiation or sham irradiation on post-transplant day 20. In the animals randomized to radiation treatment, placebo or darbepoetin alfa administration at a reduced dose was continued for 9 weeks or until the tumor diameter exceeded 15 mm (defined as failure for survival analysis). Treatment with high-dose and low-dose darbepoetin alfa produced hematocrits of 68 and 56% compared to 44 and 45% in their respective control groups (both P < 10(-5)). At 18 days post-transplant, tumor volume was not different for either darbepoetin alfa group compared to the placebo group. Tumor oxygenation, as measured by the fraction of pO2 measurement <10 mmHg and the intensity of pimonidazole staining, was significantly improved in the high-dose group (P = 0.046 and 0.03, respectively, compared with controls) but not in the low-dose group. Growth delay curves after irradiation did not differ significantly for high- or low-dose darbepoetin alfa compared to placebo. In this nonanemic animal model of mammary adenocarcinoma, darbepoetin alfa does not significantly alter tumor growth or radioresponsiveness, even though it improves oxygenation when administered at high doses.

Oxygen regulation of tumor perfusion by S-nitrosohemoglobin reveals a pressor activity of nitric oxide.

In erythrocytes, S-nitrosohemoglobin (SNO-Hb) arises from S-nitrosylation of oxygenated hemoglobin (Hb). It has been shown that SNO-Hb behaves as a nitric oxide (NO) donor at low oxygen tensions. This property, in combination with oxygen transport capacity, suggests that SNO-Hb may have unique potential to reoxygenate hypoxic tissues. The present study was designed to test the idea that the allosteric properties of SNO-Hb could be manipulated to enhance oxygen delivery in a hypoxic tumor. Using Laser Doppler flowmetry, we showed that SNO-Hb infusion to animals breathing 21% O2 reduced tumor perfusion without affecting blood pressure and heart rate. Raising the pO2 (100% O2) slowed the release of NO bioactivity from SNO-Hb (ie, prolonged the plasma half-life of the SNO in Hb), preserved tumor perfusion, and raised the blood pressure. In contrast, native Hb reduced both tumor perfusion and heart rate independently of the oxygen concentration of the inhaled gas, and did not elicit hypertensive effects. Window chamber (to image tumor arteriolar reactivity in vivo) and hemodynamic measurements indicated that the preservation of tissue perfusion by micromolar concentrations of SNO-Hb is a composite effect created by reduced peripheral vascular resistance and direct inhibition of the baroreceptor reflex, leading to increased blood pressure. Overall, these results indicate that the properties of SNO-Hb are attributable to allosteric control of NO release by oxygen in central as well as peripheral issues.

The relationship between serum vascular endothelial growth factor, persistent disease, and survival at second-look laparotomy in ovarian cancer.

OBJECTIVE: To assess if the angiogenic factors vascular endothelial growth factor (VEGF) and D-dimer are predictive of persistent disease, early relapse, and survival in patients with ovarian cancer who achieve a complete clinical remission after first-line chemotherapy. METHODS: Serum levels of VEGF and D-dimer were assessed by ELISA in 62 patients who completed first-line chemotherapy and underwent second-look laparotomy at Duke University Medical Center. Cox Proportional Hazards Modeling was utilized to determine if VEGF and/or D-dimer levels could predict disease-free and overall survival. The Kaplan-Meier method was used to estimate median survival. The Wilcoxon test was used to determine if a significant difference existed in median VEGF and D-dimer levels between patients with positive and negative second-look operations. RESULTS: Forty (65%) of the 62 women who underwent second-look laparotomy had persistent disease. The median VEGF levels were 264 pg/ml (range 109-896 pg/ml) in the group with negative second looks compared to 390 pg/ml (range 99-1011 pg/ml) in those with positive second-looks (P = 0.1). High levels of VEGF were marginally associated with the presence of persistent (P = 0.10) and gross (P = 0.07) disease at the time of second look laparotomy. After adjusting for CA125, women with high VEGF serum levels had a worse overall survival (P = 0.004). CONCLUSIONS: This study suggests that serum VEGF may be a clinically important marker for persistent disease and is predictive of survival in ovarian cancer patients after first-line chemotherapy.

HER-2 gene amplification correlates with higher levels of angiogenesis and lower levels of hypoxia in primary breast tumors.

PURPOSE: This study investigated the connection among HER-2 gene amplification, HER-2 protein expression, and markers of tumor angiogenesis and oxygenation in patients with operable, invasive breast tumors. EXPERIMENTAL DESIGN: From 1988 to 1995, 425 patients with metastatic breast cancer were enrolled in a study of high-dose chemotherapy with autologous transplant. Primary tumor blocks were obtained and evaluated using immunohistochemistry (IHC) staining of vessels with von Willebrand factor antibody. Mean microvessel densities (MVD) were determined by counting von Willebrand factor stained cells in three separate "vascular hot spots" using image analysis. Tumor samples were also stained for HER-2 by IHC, HER-2 gene amplification by fluorescence in situ hybridization, carbonic anhydrase 9 by IHC, and vascular endothelial growth factor (VEGF) by IHC. Plasma from 36 patients with primary tumor samples had VEGF (R&D Systems, MN) and d-dimer (American Diagnostica, Greenwich, CT) levels determined. RESULTS: There was a significant positive correlation between HER-2 gene amplification and both maximum and average MVD (Spearman coefficient = 0.51 and 0.50; P = 0.03 and 0.05, respectively). There was an inverse correlation with HER-2 gene amplification and expression of the tumor hypoxia marker CA-9 (chi(2) P = 0.02). The level of HER-2 gene amplification correlated with plasma d-dimer levels (Spearman coefficient = 0.43; P = 0.021). Interestingly, tumors with HER-2 by IHC had decreased amounts of VEGF staining (chi(2) = 5.81; P = 0.01). There was no correlation between HER-2 by IHC and MVD or d-dimer. Of all of the variables examined, only average (P = 0.0016) and maximum MVD (P = 0.0128) predicted disease-free survival (Cox univariate model). CONCLUSIONS: HER-2-amplified breast cancers have increased amounts of angiogenesis, decreased amounts of hypoxia, and increased markers of fibrin degradation. These findings have prognostic, predictive, and therapeutic implications in breast cancer treatment.

Circulating D-dimer levels are better predictors of overall survival and disease progression than carcinoembryonic antigen levels in patients with metastatic colorectal carcinoma.

BACKGROUND: Fibrin formation is required for tumor angiogenesis, metastasis, and invasion. D-dimer, a fibrin degradation product, is produced when crosslinked fibrin is degraded by plasmin. The current study prospectively examined D-dimer levels in patients with metastatic colorectal carcinoma treated in a Phase II randomized trial comparing bevacizumab (Avastin, Genentech, South San Francisco, CA) plus 5-fluorouracil/leucovorin (5-FU/LV) with 5-FU/LV alone. METHODS: At least one circulating D-dimer level was evaluable in 98 of the 104 previously untreated patients with metastatic colorectal carcinoma in the current trial. Plasma D-dimer levels were determined using a quantitative immunoassay kit at enrollment, before each treatment, and at the time of trial completion or disease progression. RESULTS: At trial enrollment, 86 of 104 patients (88%) had elevated D-dimer levels (> 20 ng/mL), and 86 of 102 patients (84%) had elevated carcinoembryonic antigen (CEA) levels (> 3 ng/mL). Baseline D-dimer levels were correlated with the following baseline characteristics: CEA (Pearson coefficient, 0.31; P = 0.002), albumin levels (Pearson coefficient, -0.32; P = 0.002), tumor burden (Pearson coefficient, 0.30; P = 0.003), and number of metastatic sites (Pearson coefficient, 0.21; P = 0.04). At the time of progression, plasma D-dimer levels reached a maximum postbaseline value in 51 of 61 patients (84%), whereas the CEA level was at its maximum postbaseline value in 39 of 55 patients (71%). Baseline D-dimer levels were a strong predictor of overall survival on univariate analysis (P = 0.008) and multivariate analysis (P = 0.03). Overall, treatment with bevacizumab (5 mg/kg) and baseline D-dimer levels were the only predictors of overall survival (P < 0.05). CONCLUSIONS: The current study indicates that fibrin remodeling is an important prognostic feature in metastatic colorectal carcinoma. D-dimer levels should be incorporated into prognostic models, and D-dimer may represent a useful biomarker for patients treated with antiangiogenic agents.

A 4-methyl-substituted meta-iodobenzylguanidine analogue with prolonged retention in human neuroblastoma cells.

PURPOSE: As a part of our efforts to develop a meta-iodobenzylguanidine (MIBG) analogue with improved characteristics for the diagnosis and treatment of neuroendocrine tumours, 3-[131I]iodo-4-methyl-benzylguanidine ([131I]MeIBG) has been developed. The purpose of this study was to evaluate [131I]MeIBG in vitro using the uptake-1 positive SK-N-SH neuroblastoma cell line and in vivo in normal mice and mice bearing human neuroblastoma xenografts. METHODS: The ability of SK-N-SH human neuroblastoma cells to retain [131I]MeIBG in vitro over a period of 4 days, in comparison to [125I]MIBG, was determined by a paired-label assay. Paired-label biodistributions of [131I]MeIBG and [125I]MIBG were performed in normal mice as well as in athymic mice bearing SK-N-SH and IMR-32 human neuroblastoma xenografts. RESULTS: Retention of [131I]MeIBG by SK-N-SH cells in vitro was increased by factors of 1.2, 1.5, 2.0, 2.5 and 3.1 compared with [125I]MIBG at 8, 24, 48, 72 and 96 h, respectively. In normal mice, the uptake of [131I]MeIBG in the heart was similar to that of [125I]MIBG at 1 and 4 h; in contrast, myocardial uptake of [131I]MeIBG was 1.6-fold higher than that of [125I]MIBG (p<0.05) at 24 h. When mice were pre-treated with the uptake-1 inhibitor desipramine (DMI), the heart uptake of both tracers was reduced to about half that in untreated controls at 1 h post injection (p<0.05). The hepatic uptake of [131I]MeIBG was two- to threefold lower than that of [125I]MIBG. On the other hand, blood levels of [131I]MeIBG were substantially higher (up to sixfold), especially at early time points. Uptake of [131I]MeIBG in heart and tumour at 1 h in the murine SK-N-SH model was specific and comparable to that of [125I]MIBG. However, [131I]MeIBG uptake was 1.6- to 1.7-fold lower than that of [125I]MIBG over 4-48 h. While the uptake of both tracers in IMR32 xenografts was similar, it was not uptake-1 mediated. CONCLUSION: Introduction of a methyl group at the 4-position of MIBG seems to be advantageous in terms of higher tumour retention in vitro and lower hepatic uptake in vivo. However, the slower blood clearance of MeIBG may be problematic for some applications.

Human recombinant erythropoietin significantly improves tumor oxygenation independent of its effects on hemoglobin.

Tumor oxygenation is known to be an important predictive/prognostic marker in a variety of tumors, including cervix, head/neck, sarcoma, non-small cell of the lung, and breast. Tumor oxygenation is influenced by many interactions, including oxygen delivery (angiogenesis, permeability, and HgB) and consumption (metabolic and growth rates). This study randomized 30 nonanemic, female Fischer 344 rats into three treatment arms to examine the effects of recombinant human erythropoietin (EPO) on R3230 rodent mammary carcinoma oxygenation. The three treatment arms were: (a) placebo; (b) EPO after tumor implantation (2000 units/kg/SQdose, M/W/F for six doses); and (c) EPO before tumor implantation (2000 units/kg/SQdose, M/W/F for six doses). Tumors were implanted in the hindflank, and in vivo oxygenation was measured at day 22 after implantation using the Oxylite system (Oxford Optronix, Oxford, England). An average of 180 measurements/animal were performed. On day 22, median tumor volume was 399 mm(3) (range: 65-950 mm(3)), and no differences in tumor volume were seen between treatment arms. Mean hematocrit was equal between arms at therapy initiation but were significantly higher for both arms receiving EPO at day 22 (placebo versus Arm B versus Arm C; Wilcoxon P = 0.052). EPO-treated tumors had significantly less hypoxic measurements when compared with either the placebo or those receiving EPO before implantation. These data confirm that tumor oxygenation in nonanemic individuals may be improved through the administration of EPO, and this improvement appears to be independent of HgB effects.