Image quality and radiation dose of renal perfusion CT with low-dose contrast agent: a comparison with conventional CT using a 320-row system.

AIM: To compare perfusion computed tomography (CT) with reconstructed image from source data using low-dose contrast agent and conventional 320-row CT for the evaluation of renal tumours. MATERIALS AND METHODS: Twenty-eight patients underwent conventional CT (C-CT) and 26 patients underwent perfusion CT with low-dose (40 ml) contrast agent. Image noise, arterial visualisation, the sharpness of the corticomedullary junction (CMJ), and overall image quality were each assessed using a four-point scale. The tumour detection rate for lesions <4 cm (n=66) was also evaluated. Quantitative image parameters including image noise and the contrast-to-noise ratios (CNRs) of the renal artery and CMJ were measured. The volume CT dose index (CTDI), dose-length product (DLP), and size-specific dose estimate (SSDE) were also recorded. RESULTS: Although the image noise of perfusion CT was higher than that of C-CT and the overall image quality of perfusion CT was lower than that of C-CT, the arterial visualisation score of perfusion CT was significantly higher than that of C-CT. The CMJ sharpness scores of the two techniques were equivalent. Sensitivity and positive predictive values were also equivalent with respect to tumour detection. The CNRs of both the left and right renal arteries were significantly higher on perfusion CT than on C-CT. The CTDI, DLP, and SSDE of perfusion CT were significantly lower than those of C-CT. CONCLUSION: Perfusion CT using low-dose contrast agent preserved arterial visualisation and the tumour detection rate and achieved a low radiation dose despite image quality degradation and image noise.

Transcriptional CCND1 expression as a predictor of poor response to neoadjuvant chemotherapy with trastuzumab in HER2-positive/ER-positive breast cancer.

Several trials have confirmed that the pathological complete response (pCR) rates after neoadjuvant chemotherapy (NAC) are significantly lower in HER2-positive/ER-positive patients than in HER2-positive/ER-negative patients. To understand this phenomenon, we investigated the association between NAC resistance and CCND1, which is frequently overexpressed in ER-positive tumors. Pretreatment formalin-fixed tumor tissues were collected from 75 HER2-positive patients receiving NAC comprised anthracyclines, taxanes, and trastuzumab. Seventeen gene transcripts along with PIK3CA mutations were detected using MassARRAY (Sequenom, San Diego, CA). The gene expression levels were dichotomized according to the median values. The immunohistochemical expression of ER, PTEN, BCL-2, and cyclin D1 was scored. The relationship between the variables was assessed using the Spearman correlation. A logistic regression analysis was performed to detect predictors of pCR, which was defined as no invasive tumor in the breast or axilla. Forty-seven percent of the cases were ER-positive and 52 % (40/63 % in ER-positive/ER-negative) achieved a pCR. Among the ER-positive patients, the CCND1 gene expression level was 2.1 times higher than that in ER-negative patients and was significantly correlated with the expression of cyclin D1 protein. In a univariate analysis, a pCR was associated with high mRNA levels of ESR1, PGR, LMTK3, HER2, IGF1R, INPP4B, PDL-1, BCL-2, and CCND1 (P ≤ 0.05). In contrast, none of these genes were significantly correlated with a pCR among the ER-negative tumors and only EGFR was significantly correlated with a pCR. PIK3CA mutations or PTEN loss were not associated with a pCR in either group. After excluding ESR1 (r = 0.58), PGR (r = 0.64), and IGF1R (r = 0.59), the expressions of which were correlated with CCND1, a multivariate analysis revealed that CCND1 [P = 0.043; OR, 0.16] and HER2 [P = 0.012; OR, 11.2] retained its predictive value for pCR among ER-positive patients, but not among ER-negative patients. A High Level of CCND1 gene expression is a poor predictor of a pCR and provides a rationale for evaluating CDK4/6 inhibitors in HER2-positive/ER-positive breast cancer patients.

Survival of HER2-positive primary breast cancer patients treated by neoadjuvant chemotherapy plus trastuzumab: a multicenter retrospective observational study (JBCRG-C03 study).

We investigated the disease-free survival (DFS) of HER2-positive primary breast cancer patients treated with neoadjuvant chemotherapy plus trastuzumab, as well as predictive factors for DFS and pathologic response. Data from 829 female patients treated between 2001 and 2010 were collected from 38 institutions in Japan. Predictive factors were evaluated using multivariate analyses. The 3-year DFS rate was 87 % [95 % confidence interval (CI) 85-90]. The pathologic complete response (pCR: ypT0/is + ypN0) rate was 51 %. The pCR rate was higher in the ER/PgR-negative patients than in the ER/PgR-positive patients (64 vs. 36 %, P < 0.001). Patients with pCR showed a higher DFS rate than patients without pCR (93 vs. 82 %, P < 0.001). Multivariate analysis revealed three independent predictors for poorer DFS: advanced nodal stage [hazard ratio (HR) 2.63, 95 % CI 1.36-5.21, P = 0.004 for cN2-3 vs. cN0], histological/nuclear grade 3 (HR 1.81, 95 % CI 1.15-2.91, P = 0.011), and non-pCR (HR 1.98, 95 % CI 1.22-3.24, P = 0.005). In the ER/PgR-negative dataset, non-pCR (HR 2.63, 95 % CI 1.43-4.90, P = 0.002) and clinical tumor stage (HR 2.20, 95 % CI 1.16-4.20, P = 0.017 for cT3-4 vs. cT1-2) were independent predictors for DFS, and in the ER/PgR-positive dataset, histological grade of 3 (HR 3.09, 95 % CI 1.48-6.62, P = 0.003), clinical nodal stage (HR 4.26, 95 % CI 1.53-13.14, P = 0.005 for cN2-3 vs. cN0), and young age (HR 2.40, 95 % CI 1.12-4.94, P = 0.026 for ≤40 vs. >40) were negative predictors for DFS. Strict pCR (ypT0 + ypN0) was an independent predictor for DFS in both the ER/PgR-negative and -positive datasets (HR 2.66, 95 % CI 1.31-5.97, P = 0.006 and HR 3.86, 95 % CI 1.13-24.21, P = 0.029, respectively). These results may help assure a more accurate prognosis and personalized treatment for HER2-positive breast cancer patients.

Prevalence of and risk factors for depressive symptoms in non-tuberculous mycobacterial pulmonary disease.

BACKGROUND: The presence of depressive symptoms in patients with non-tuberculous mycobacterial pulmonary disease (NTM-PD) is an important research topic; however, the prevalence of depressive symptoms and the factors that influence their development are unclear.OBJECTIVE: To analyse the association between CES-D (Center for Epidemiological Studies Depression Scale) scores and clinical parameters such as age, disease duration, pulmonary function, imaging findings, blood data, physical functions, sleep disturbances, respiratory symptoms and health-related quality of life (HRQOL).METHODS: We conducted a cross-sectional retrospective study of 114 patients with NTM-PD at a single centre from March 2016 to January 2021 to evaluate the relationship between CES-D scores and clinical parameters.RESULTS: Participants had a median age of 64 years; 32.5% of them had depressive symptoms. Disease duration, albumin, C-reactive protein, pulmonary function, dyspnoea, exercise capacity, respiratory symptoms, cough-related HRQOL and sleep disturbances were associated with depressive symptoms. Binomial logistic regression analyses indicated that the CES-D score was significantly associated with cough-related HRQOL and sleep disturbances.CONCLUSION: A high percentage of NTM-PD patients in this study experienced depressive symptoms, and these patients had abnormalities of various clinical parameters. Cough-related HRQOL and sleep disturbance had a strong influence on the development of depressive symptoms.

Health-related quality of life associates with clinical parameters in patients with NTM pulmonary disease.

BACKGROUND: Previous studies have shown a reduction in health-related quality of life (HRQoL) in patients with non-tuberculous mycobacterial pulmonary disease (NTM-PD). However, the causes of this decline and the factors that contribute to it are unknown. This study was conducted to analyse the association between the St George´s Respiratory Questionnaire (SGRQ) and clinical parameters, including age, disease duration, body composition, pulmonary function, chest X-ray findings, blood data and physical function.METHODS: We performed a single-centre, cross-sectional, retrospective study of 101 patients with NTM-PD from December 2016 to October 2019. The relationship between the SGRQ scores and clinical parameters was evaluated.RESULTS: The median patient age was 67.0 years. Pulmonary function, radiological score, albumin levels, C-reactive protein levels and incremental shuttle walk test distance (ISWD) were significantly correlated with the total and component scores on the SGRQ. Multiple regression analysis showed that the SGRQ score was significantly associated with radiological score, pulmonary function and ISWD.CONCLUSION: This study was the first to assess the effect of clinical parameters on the SGRQ in patients with NTM-PD. HRQoL as determined using the SGRQ was associated with the radiological score, pulmonary function and ISWD in patients with NTM-PD.

CD133 expression is correlated with lymph node metastasis and vascular endothelial growth factor-C expression in pancreatic cancer.

Although CD133 has been shown to be a marker for cancer stem cells in various tumours, its expression in pancreatic cancer has not yet been clinically reported. In this study, we investigated the relationship between CD133 expression and clinicopathological factors in pancreatic cancer. Pancreatic head carcinoma specimens from 80 patients who underwent surgical resection were immunohistochemically assessed for CD133, vascular endothelial growth factor (VEGF)-C, CXCR4, CD34, Ki-67, and cytokeratin (CK) expressions. Sixty percentage (48/80) of specimens were CD133-positive, with less than 15% cells per specimen expressing the marker. CD133-positive cells were found at the peripheral site of adenocarcinoma glandular structures and were negative for CK. There was a significant correlation between CD133 expression and clinicopathological factors, including histological type, lymphatic invasion, and lymph node metastasis (P=0.0215, 0.0023, and 0.0024, respectively). Vascular endothelial growth factor-C expression was also significantly correlated with CD133 expression (P=0.0002). Consequently, the 5-year survival rate of CD133-positive patients was significantly lower than that of CD133-negative patients (P=0.0002) and multivariate analysis revealed that CD133 expression was an independent prognostic factor (P=0.0103). These results suggest that CD133 expression in pancreatic cancer was significantly associated with lymphatic metastasis, VEGF-C expression, and prognosis.

Targeting the vulnerability to NAD+ depletion in B-cell acute lymphoblastic leukemia.

Although substantial progress has been made in the treatment of B-cell acute lymphoblastic leukemia (B-ALL), the prognosis of patients with either refractory or relapsed B-ALL remains dismal. Novel therapeutic strategies are needed to improve the outcome of these patients. KPT-9274 is a novel dual inhibitor of p21-activated kinase 4 (PAK4) and nicotinamide phosphoribosyltransferase (NAMPT). PAK4 is a serine/threonine kinase that regulates a variety of fundamental cellular processes. NAMPT is a rate-limiting enzyme in the salvage biosynthesis pathway of nicotinamide adenine dinucleotide (NAD) that plays a vital role in energy metabolism. Here, we show that KPT-9274 strongly inhibits B-ALL cell growth regardless of cytogenetic abnormalities. We also demonstrate the potent in vivo efficacy and tolerability of KPT-9274 in a patient-derived xenograft murine model of B-ALL. Interestingly, although KPT-9274 is a dual PAK4/NAMPT inhibitor, B-ALL cell growth inhibition by KPT-9274 was largely abolished with nicotinic acid supplementation, indicating that the inhibitory effects on B-ALL cells are mainly exerted by NAD+ depletion through NAMPT inhibition. Moreover, we have found that the extreme susceptibility of B-ALL cells to NAMPT inhibition is related to the reduced cellular NAD+ reserve. NAD+ depletion may be a promising alternative approach to treating patients with B-ALL.

Ordering of mutations in acute myeloid leukemia with partial tandem duplication of MLL (MLL-PTD).

Partial tandem duplication of MLL (MLL-PTD) characterizes acute myeloid leukemia (AML) patients often with a poor prognosis. To understand the order of occurrence of MLL-PTD in relation to other major AML mutations and to identify novel mutations that may be present in this unique AML molecular subtype, exome and targeted sequencing was performed on 85 MLL-PTD AML samples using HiSeq-2000. Genes involved in the cohesin complex (STAG2), a splicing factor (U2AF1) and a poorly studied gene, MGA were recurrently mutated, whereas NPM1, one of the most frequently mutated AML gene, was not mutated in MLL-PTD patients. Interestingly, clonality analysis suggests that IDH2/1, DNMT3A, U2AF1 and TET2 mutations are clonal and occur early, and MLL-PTD likely arises after these initial mutations. Conversely, proliferative mutations (FLT3, RAS), typically appear later, are largely subclonal and tend to be unstable. This study provides important insights for understanding the relative importance of different mutations for defining a targeted therapeutic strategy for MLL-PTD AML patients.

Multidrug resistance and the lung resistance-related protein in human colon carcinoma SW-620 cells.

BACKGROUND: Lung resistance-related protein (LRP), the major vault protein in humans, is sometimes overexpressed in multidrug-resistant cells. Because cells transfected with the LRP gene did not express the multidrug-resistant phenotype, we investigated whether LRP is involved in multidrug resistance. METHODS: SW-620 cells, a human colon carcinoma cell line, alone or transfected with an expression vector carrying a LRP-specific ribozyme or with an empty vector, were treated with sodium butyrate to induce differentiation. Expression of P-glycoprotein, multidrug resistance protein, and LRP in the cells was examined by northern and western blotting, and the efflux of doxorubicin in the cells or isolated nuclei was examined by fluorescence microscopy. RESULTS: A 2-week treatment with sodium butyrate induced LRP and conferred resistance to doxorubicin, vincristine, etoposide, gramicidin D, and paclitaxel (Taxol) in SW-620 cells. Insertion of either of two LRP-specific ribozymes into SW-620 cells inhibited these activities. Levels of drugs accumulating in the cells were not decreased by sodium butyrate, suggesting that the adenosine triphosphate-binding cassette transporter is not involved in sodium butyrate-induced multidrug resistance. Doxorubicin was mainly located in the nuclei of untreated cells and in the cytoplasm of sodium butyrate-treated cells. Isolated nuclei from untreated cells or sodium butyrate-treated cells incubated with anti-LRP polyclonal antibodies contained more doxorubicin than the nuclei of sodium butyrate-treated cells alone. Efflux of doxorubicin was greater from the nuclei of sodium butyrate-treated cells than the nuclei of untreated cells or of sodium butyrate-treated cells transfected with a LRP-specific ribozyme and was inhibited by an anti-LRP polyclonal antibody. CONCLUSIONS: LRP is involved in resistance to doxorubicin, vincristine, etoposide, paclitaxel, and gramicidin D and has an important role in the transport of doxorubicin from the nucleus to the cytoplasm.

A modified invasion-3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyltetrazolium bromide assay for quantitating tumor cell invasion.

Reconstituted basement membrane matrix (Matrigel) has been utilized for in vitro assay of tumor cell invasion in recent years. In the conventional chamber for the invasion assay, however, a large number of cells passed easily through the center of the Matrigel-coated filter because the Matrigel layer could not be completely uniform by the meniscus formation. To prevent the meniscus phenomenon of the Matrigel layer, we devised a water-repellent treatment of the inside wall of the assay chamber with paraffin. Consequently, very few erythrocytes passed through the Matrigel-coated filter of this modified chamber with the erythrocyte assay, which was used to demonstrate the evenness and uniformity of the Matrigel layer on the filter. For quantitating a small number of cells which invaded through the Matrigel-coated filter by the invasion assay, a tetrazolium-based colorimetric 3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyltetrazolium bromide) assay was used. The invasive abilities of the eight different cells were determined by this invasion-3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyltetrazolium+ ++ bromide assay using the modified chamber with a filter coated with 70 microliters of the 0.2-mg/ml Matrigel. After 72 h of incubation, the malignant cell lines significantly exceeded the normal cell lines in the percentage of invasion (P < 0.01). Therefore, the modified invasion-3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyltetrazolium+ ++ bromide assay provides a simple, easily reproducible in vitro assay for quantitating tumor cell invasion.

In vitro determination of basement membrane invasion predicts liver metastases in human gastrointestinal carcinoma.

We described previously (H. Imamura, et al., Cancer Res., 54: 3620-3624, 1994) a quantitative and reproducible 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay for tumor cell invasiveness that uses a water-repellent, paraffin-treated Chemotaxicell chamber to produce a uniform Matrigel layer. In the present experiments, we studied 71 human gastrointestinal carcinomas, including 53 maintained as xenografts in nude mice and 18 fresh surgical specimens. We found a correlation between metastatic behavior and the percent invasion (PI) calculated from the MTT assay. Tumors producing liver metastases had a significantly higher PI than did tumors without liver metastases (P < 0.01), and seven of nine fresh tumors with a PI greater than 1.0 showed liver metastases within 2 years. No significant correlations were noted between the PI and clinicopathological factors. In the tumor xenografts, type IV collagenase activity was significantly higher in tumors with clinically evident liver metastases than in those without liver metastases (P < 0.05). Colorectal carcinomas with liver metastases and a high PI showed higher expression of matrix metalloproteinase 9 than matrix metalloproteinase 2 as assessed by gelatin zymography. Thus, the invasion-MTT assay is clinically useful for predicting liver metastases. Type IV collagenase plays an important role in the development of liver metastases from human gastrointestinal carcinoma.

Effect of a dihydropyridine analogue, 2-[benzyl(phenyl)amino]ethyl 1,4-dihydro-2,6-dimethyl-5-(5,5-dimethyl-2-oxo- 1,3,2-dioxaphosphorinan-2-yl)-1-(2-morpholinoethyl)-4-(3-nitrophenyl)-3 -pyridinecarboxylate on reversing in vivo resistance of tumor cells to adriamycin.

A newly synthesized dihydropyridine analogue, 2-[benzyl(phenyl)-amino]ethyl 1,4-dihydro-2,6-dimethyl-5-(5,5-dimethyl-2-oxo-1,3,2-dioxaphosphorina n-2-yl)-1- (2-morpholinoethyl)-4-(3-nitrophenyl)-3-pyridinecarboxylate (PAK-200), at 5 microM inhibited the efflux of [3H]vincristine from KB-C2 cells and increased the accumulation of [3H]vincristine in KB-C2 cells to a level similar to that in KB-3-1 cells. PAK-200 inhibited the photoaffinity labeling of P-glycoprotein in KB-C2 membranes by [3H]azidopine. At 5 microM, PAK-200 enhanced the cytotoxic effect of Adriamycin on drug-sensitive KB-3-1 cells, multidrug-resistant KB-8-5 cells, and two human colorectal carcinoma tumor lines, COK-28LN and COK-36LN, by factors of 2, 5, 2, and 3 times, respectively. The calcium antagonistic activity of PAK-200 was about 1000 and 5 times lower than that of another dihydropyridine analogue, nicardipine, and of verapamil, respectively. PAK-200 in combination with Adriamycin completely suppressed the growth of KB-3-1 and COK-36LN and partially suppressed the growth of KB-8-5 but had no significant effect on COK-28LN cells xenografted in nude mice. The level of MDR1 expression of COK-36LN was about 3 times higher than that of COK-28LN, but lower than that of KB-8-5 cells. These results suggest that the interaction of PAK-200 with P-glycoprotein may be partly correlated with the enhancement of the antitumor effect of Adriamycin on xenografted KB-8-5 and COK-36LN cells in nude mice.

A new family of heparin-binding growth/differentiation factors: increased midkine expression in Wilms' tumor and other human carcinomas.

Midkine (MK) and heparin-binding growth-associated molecule/pleiotrophin form a new family of heparin-binding growth/differentiation factors. We studied MK gene expression in human tumors. In normal human reference tissues, MK was highly expressed in the mucosal tissue of the small intestine, moderately in the thyroid, weakly in the tissues of the lung, colon, stomach, kidney, and spleen, and not at all in the liver. All of 6 surgically removed specimens of Wilms' tumor highly expressed MK. Also, a moderate to intense level of MK expression was noted in the majority of surgically removed hepatocellular carcinomas. The MK mRNA level was analyzed in a number of cultured and nude mice-transplanted lines of human tumors. In stomach, colon, pancreatic, lung, and esophageal carcinomas, a moderate to high level of MK expression was found in the majority of them. These results suggest an important role of MK in the development and/or biological behavior of tumors and raised a possibility to use MK as a diagnostic marker. Heparin-binding growth associated molecule/pleiotrophin mRNA was low or scarcely detectable in samples analyzed thus far except for significant levels of the expression that were observed in PA-1 teratocarcinoma cells and in some surgical specimens of Wilms' tumor.

Suppression of metastasis by thymidine phosphorylase inhibitor.

We developed a novel inhibitor of thymidine phosphorylase (TP), 5-chloro-6-[1-(2-iminopyrrolidinyl) methyl] uracil hydrochloride (TPI), that is about 1000-fold more active than 6-amino-5-chlorouracil, one of the most potent TP inhibitors. TPI inhibited the high chemotactic motility and basement membrane invasion of KB/TP cells, a TP-positive clone transfected with Rous sarcoma virus (RSV)/TP, to the levels seen in KB/CV cells, a control clone transfected with RSV. In nude mice, oral administration of TPI suppressed not only macroscopic liver metastases of highly metastatic KB/TP cells but also the level of human beta-globin as a molecular marker of micrometastases in the livers of the mice. These findings demonstrate that TP plays a key role in the invasiveness and metastasis of TP-expressing solid tumors and suggest that TPI might be a novel antimetastatic agent for blood-borne metastasis.

MUC4 expression is a novel prognostic factor in patients with invasive ductal carcinoma of the pancreas.

BACKGROUND: Many patients with invasive ductal carcinoma of the pancreas (IDC) have a poor outcome. MUC4 expression has been implicated as a marker for diagnosis and progression of IDC, but there are no studies of the relation between MUC4 expression and patient prognosis in IDC. AIMS: To investigate the prognostic significance of MUC4 expression in IDC. METHODS: The expression profiles of MUC4, ErbB2, p27, and MUC1 were investigated in IDC tissues from 135 patients by means of immunohistochemistry. RESULTS: MUC4 was expressed in 43 of the 135 patients with IDC (31.9%). The survival of 21 patients with high MUC4 expression (>20% of neoplastic cells stained) was significantly worse than that of the 114 patients with low MUC4 expression (<20% of neoplastic cells stained) (p = 0.0043). Univariate analysis showed that high MUC4 expression (p = 0.0061), large primary tumour status (>T2) (p = 0.0436), distant metastasis (p = 0.0383), lymphatic invasion (p = 0.0243), and surgical margins (p = 0.0333) were significant risk factors affecting the outcome of patients with IDC. Backward stepwise multivariate analysis showed that MUC4 expression (p = 0.0121), lymph node metastasis (p = 0.0245), and lymphatic invasion (p = 0.0239) were significant independent risk factors. ErbB2, p27, and MUC1 were not independent risk factors. CONCLUSIONS: This study shows that MUC4 expression in IDC is a new independent factor for poor prognosis and predicts the outcome of patients with IDC.

Expression of p21WAF1/Cip1 in the p53-dependent pathway is related to prognosis in patients with advanced esophageal carcinoma.

The proteins p53 and p21 are important components that regulate G1-S transition through the cell cycle. We immunohistochemically investigated p53 and p21 expression in 111 patients with esophageal squamous cell carcinoma. We also evaluated whether the expression of either of these proteins is a prognostic factor according to the p53-dependent and -independent pathways. The positive rates of p53 and p21 expression were 42.8 and 43.2%, respectively. Clinicopathological findings according to p53 and p21 expression did not differ significantly. The 5-year-survival rates between p21 positive and negative expression did not differ significantly in the p53-positive group. In the p53-negative group, the 5-year-survival rate of patients with p21-positive expression was 22.9%, which was significantly better than that of patients with p21-negative expression (12.7%; P<0.05). Multivariate analysis revealed that p21 expression in the p53-dependent pathway was an independent prognostic factor. Accordingly, the prognostic values of p21 expression between the p53-dependent and -independent pathways differed. Examination of p21-positive expression in the p53-dependent pathway will help to estimate the favorable prognosis of patients with advanced esophageal carcinoma.

Expression of thymidine phosphorylase is associated with a poor prognosis in patients with ductal adenocarcinoma of the pancreas.

Thymidine phosphorylase (dThdPase) is identical to platelet-derived endothelial cell growth factor and has angiogenic activity. In this study, we investigated the expression of dThdPase in ductal adenocarcinoma of the pancreas and examined the correlation between dThdPase expression and clinicopathological factors and clinical outcome. dThdPase expression was demonstrated by immunohistochemistry in the cytoplasm of tumor cells in 59% of the 54 patients studied. The expression of dThdPase correlated significantly with a poor prognosis (P=0.013). Significant correlations were also observed between dThdPase expression and extrapancreatic neural plexus invasion and the presence of postoperative hepatic metastases (P=0.05 and 0.03, respectively). The average microvessel count in dThdPase-positive tumors was significantly higher than that in dThdPase-negative tumors (P < 0.0001). These findings suggest that dThdPase expression in pancreatic adenocarcinoma enhances the abilities of tumor invasion and/or metastasis through its angiogenic properties.

Preserved Smad4 expression in the transforming growth factor beta signaling pathway is a favorable prognostic factor in patients with advanced gastric cancer.

The signals of the transforming growth factor beta (TGF-beta) superfamily are conveyed through cell surface serine/threonine kinase receptors to the intracellular mediators known as Smads. Activation of Smads causes their translocation from the cytoplasm to the nucleus, where they function to control gene expression. The present study analyzed the expression of Smad4 and TGF-beta1 to determine their prognostic significance in advanced gastric cancer. Of 249 cases of advanced gastric cancer, 41 had invaded the muscular layer, 114 had invaded the subserosal layer, and 94 had invaded the serosa. Anti-Smad4 and TGF-beta1 antibodies were used for immunohistochemical staining. Reduced expression of Smad4 was 75.1%, whereas positive expression of TGF-beta1 was 39.6% in gastric cancer. Smad4 expression was related to the depth of tumor invasion (P < 0.05), and TGF-beta1 expression correlated with tumor gross type (P < 0.05). Postoperative survival analysis indicated that patients who had a tumor with reduced Smad4 expression had a poorer clinical outcome than those with preserved expression (P < 0.05). Furthermore, in patients with TGF-beta1-positive tumors, survival rate was significantly better in patients with preserved Smad4 expression than in those with reduced Smad4 expression (P < 0.05). According to multivariate analysis, Smad4 expression acted as an independent prognostic factor. Smad4 expression, particularly in the TGF-beta pathway, is an effective predictor of outcome for patients with advanced gastric cancer.

Endothelial cells potentiate oxidant-mediated Kupffer cell phagocytic killing.

Phagocytosis and killing of circulating organisms by Kupffer cells (KCs) are discrete, important components of host defense. However, the killing mechanism(s) are not fully understood, and the potential role of adjacent nonparenchymal cells such as hepatic endothelial cells has not been defined. Rat KCs -/+ an hepatic endothelial cell enriched cellular fraction (HECEF) were incubated with Candida parapsilosis and assayed for phagocytosis and phagocytic killing by validated fluorochromatic vital staining. The role of reactive oxygen metabolites in KC phagocytic functions was examined by inhibition with superoxide dismutase and/or catalase. Diphenyleneiodonium and allopurinol were used to examine the potential roles of NADPH oxidase and xanthine oxidase, respectively, in generating these toxic oxidants. Coculture with HECEF increased KC phagocytic activity (from 75% to 88%) and candidacidal activity (from 20% to 31%). Superoxide dismutase, catalase, diphenyleneiodonium, or allopurinol caused inhibition of candidacidal activity, but did not affect phagocytosis, and did not block the potentiation of phagocytosis or of killing caused by coculture with HECEF. Reactive oxygen intermediates generated by both NADPH oxidase and xanthine oxidase-dependent pathways are important in KC killing of Candida parapsilosis. In vitro, KC phagocytosis and killing are potentiated (via a non-oxidant-mediated mechanism) by coculture with a preparation of hepatic non-parenchymal cells composed primarily of endothelial cells.