Early visual processing relevant to the reduction of adaptation-induced perceptual bias.

Visual perception is biased by the preceding visual environment. A well-known perceptual bias is the negative bias where a current percept is biased away from the preceding image (adaptor). The preceding adaptor induces augmentation of early visual evoked potential (the P1 enhancement) of the following test image; the adaptor may invoke certain visual processing for the subsequent test image. However, the visual mechanism underlying P1 enhancement remains unclear. The present study assessed what the P1 alteration reflects in relation to the occurrence of the negative bias. In terms of inter-individual differences, we report that the P1 enhancement of the Necker lattice significantly correlated with the reduction of the reverse-bias effect. Further analyses revealed that the P1 enhancement was insusceptible to neural adaptation to the adaptor at the level of perceptual configuration. The present study suggests that prolonged exposure to a visual image induces modulatory visual processing for the subsequent image (reflected in the P1 enhancement), which is relevant to counteraction of the negative bias.

Genetic influence of cytokine polymorphisms on the clinical outcome of Japanese gastrointestinal cancer patients in palliative care.

Gastrointestinal cancer is one of the most common causes of mortality globally. The present study examined the influence of cytokine genetic polymorphisms [interleukin (IL)-1B C-31T, IL-1RN VNTR, IL-6 C-634G, IL-8 T-251A, IL-10 T-819C and IL-10 A-1082G] on clinical outcomes in patients with gastrointestinal cancer in palliative care. A total of 59 patients with gastrointestinal cancer who were admitted to Iga City General Hospital were analyzed. Genotyping was conducted using a polymerase chain reaction with confronting two-pair primers. Patients with at least one IL-1RN 2 allele demonstrated a significantly better survival (P=0.0275) while those with IL-6-634 G/G demonstrated a worse survival (P=0.0024). Multivariate analyses using the Cox proportional hazard model revealed that those with at least one IL-1RN 2 allele, IL-6-634 G/G or IL-10-1082 A/G had a significantly elevated adjusted hazard ratio of 9.20 (P=0.014), 41.01 (P=0.001) or 6.49 (P=0.046), respectively, compared with those with each homozygous wild-type polymorphism. In addition, the evaluation of weight loss by genotype revealed the potential influence of IL-10 T-819C genotype (P=0.072). IL-1RN, IL-6 and IL-10 polymorphisms were associated with the survival of patients with gastrointestinal cancer, suggesting the clinical feasibility of genetic testing in patients with gastrointestinal cancer in palliative care.

Correlation Between Gait Perception and Autistic Traits in the General Population: A Study on Event-Related Evoked Potentials.

Previous studies have shown that people with autistic traits have difficulties in motion perception, such as human gait as depicted on a point-light display. A recent study reported that adults with autism spectrum disorders showed atypical visual event-related evoked potentials (ERPs) in response to radial optic flow. To determine the correlation between gait perception and autistic traits in the general population, the present study recorded ERPs time-locked to the onset of approaching and receding point-light walkers. ERPs were measured using an 8-channel system in 19 adults and the correlation between the ERP components and the Subthreshold Autism Trait Questionnaire (SATQ) score were assessed to quantitatively measure autistic traits in the general population. The results showed that the higher SATQ score was, the longer the latency of the ERP component for an approaching walker was. In conclusion, people with autistic traits have trouble perceiving the approach of other people.

Polymorphisms in folic acid metabolism genes do not associate with cancer cachexia in Japanese gastrointestinal patients.

We used clinical data from Iga General Hospital to examine the association between polymorphisms in MTR (methionine synthase) A2756G (rs1805087), MTRR (methionine synthase reductase) His595Tyr (rs10380), MTHFR (methylenetetrahydrofolate reductase) C677T (rs1801133), MTHFR A1298C (rs1801131) and SHMT (serine hydroxymethyltransferase) C1420T (rs1979277), which are genes involved in folate metabolism, and the risk of weight loss in patients with gastrointestinal cancers, with the aim of establishing personalized palliative care for each patient based on genetic information. The data from 59 patients (37 males and 22 females) with gastrointestinal cancers who visited the outpatient clinic for cancer chemotherapy and palliative care at Iga General Hospital from December 2011 to August 2015 were analyzed. There was no significant association between the single nucleotide polymorphisms (SNPs) in the folate metabolizing genes examined and weight loss defined as weight loss of more than 5 percent or more than 10 percent during the first 6 months after initiation of chemotherapy. We did not detect any significant association between any of the SNPs examined and overall survival of patients. The present study indicated that these SNPs have relatively limited or no roles in the genesis of cachexia in patients with gastrointestinal cancers; however, further investigations into the roles of these folate metabolizing genes in the context of cancer palliative care, from clinical, biological and epidemiological viewpoints are warranted.

Colony-stimulating factor-1 and colony-stimulating factor-1 receptor co-expression is associated with disease progression in gastric cancer.

Colony­stimulating­factor­1 (CSF­1) is a hematopoietic growth factor that exerts its effects through the c­fms/CSF­1 receptor (CSF­1R). The CSF­1/CSF­1R axis is thought to be involved in the development of several types of cancer. This study aimed to clarify the clinical and biological significance of the CSF­1/CSF­1R axis in gastric cancer (GC). For this purpose, we evaluated CSF­1 and CSF­1R expression in GC tissues from 148 patients by RT­qPCR and immunohistochemistry. The biological roles of the CSF­1/CSF­1R axis were investigated by measuring the cell proliferation and migration, and anoikis resistance in a human GC cell line following treatment with recombinant human CSF­1 and/or CSF­1R inhibitor. The results revealed that an elevated expression of CSF­1 or CSF­1R significantly correlated with disease progression and with a poor overall survival (OS, P=0.037 and 0.016, respectively) and disease­free survival (DFS, P<0.001 and <0.001, respectively) of patients with GC. Furthermore, a high co­expression of CSF­1 and CSF­1R was an independent prognostic factor for OS (HR, 1.38; 95% CI, 1.02­1.88; P=0.038) and DFS (HR, 1.79; 95% CI, 1.21­2.67; P=0.004), and an independent risk factor for lymph node and peritoneal metastasis. Immunohistochemical analysis revealed an intense CSF­1/CSF­1R expression in the cytoplasm of cancer cells in primary GC tissues. CSF­1 or CSF­1R expression positively correlated with vascular endothelial growth factor A (VEGFA) or Fms related tyrosine kinase 1 (FLT1) expression in GC tissues. Treatment with recombinant human CSF­1 promoted proliferation, migration and anoikis resistance in a GC cell line. These effects were generally blocked by CSF­1R inhibition. On the whole, the findings of this study indicate that the CSF­1/CSF­1R axis may be a clinically useful prognostic and predictive biomarker for lymph node and peritoneal metastasis and a potential therapeutic target in GC.

Clinical Burden of Modified Glasgow Prognostic Scale in Colorectal Cancer.

BACKGROUND/AIM: This study aimed to clarify the potential of modified Glasgow Prognostic Score (mGPS) as a prognostic biomarker and reveal the significance of fish oil (FO)-enriched nutrition in colorectal cancer (CRC). PATIENTS AND METHODS: A total of 738 CRC patients from three different patient cohorts, including 670 patients in the biomarker study and 68 patients in the nutrition-intervention study, were analyzed. RESULTS: High preoperative mGPS was significantly correlated with well-recognized disease progression factors and advanced UICC stage classification. In addition, high mGPS was an independent prognostic factor in both cohorts, especially in stage III and IV patients. These statuses were maintained in postoperative course and correlated with sarcopenia. Furthermore, FO-enriched nutrition suppressed systemic inflammatory reaction and improved skeletal muscle mass and prognosis, especially in CRC patients with mGPS 1 or 2. CONCLUSION: Assessment of mGPS could identify patients with high-risk CRC, who might be candidates for FO-enriched nutrition.

Fish oil-enriched nutrition combined with systemic chemotherapy for gastrointestinal cancer patients with cancer cachexia.

Despite recent advances in chemotherapy for gastrointestinal cancer, a crucial factor related to poor prognosis is reduced tolerance to chemotherapy induced by cancer cachexia. Fish oil (FO)-derived eicosapentaenoic acid (EPA) modulates inflammation in patients with various malignancies; however, the impact of FO-enriched nutrition as a combined modality therapy on clinical outcomes remains controversial. We systemically analysed chronological changes in biochemical and physiological status using bioelectrical impedance analysis in 128 gastrointestinal cancer patients provided with or without FO-enriched nutrition during chemotherapy. Furthermore, we evaluated the clinical significance of FO-enriched nutrition and clarified appropriate patient groups that receive prognostic benefits from FO-enriched nutrition during treatment of gastrointestinal cancer. The control group showed significant up-regulation of serum CRP) levels and no significant difference in both skeletal muscle mass and lean body mass. In contrast, the FO-enriched nutrition group showed no changes in serum CRP concentration and significantly increased skeletal muscle mass and lean body mass over time. Furthermore, high CRP levels significantly correlated with reduced tolerance to chemotherapy, and FO-enriched nutrition improved chemotherapy tolerance and prognosis, particularly in gastrointestinal cancer patients with a modified Glasgow prognostic score (mGPS) of 1 or 2. We conclude that FO-enriched nutrition may improve the prognosis of patients with cancer cachexia and systemic inflammation (i.e., those with a mGPS of 1 or 2).

Objective Predictive Score as a Feasible Biomarker for Short-term Survival in TerminalIy Ill Patients with Cancer.

BACKGROUND: In palliative care, prediction of life expectancy is one of the most crucial issues for patients, family and medical staff, in order to provide appropriate end-of-life care. The aim of this study was to formulate a new objective score to predict life expectancy within 1 week for terminally ill patients with cancer. PATIENTS AND METHODS: Medical records were obtained from 187 terminally-ill patients with cancer who were admitted for palliative care. The biomarkers for a potential 'Objective Predictive Score' were assessed. RESULTS: Profiling of blood parameters demonstrated that elevated levels of alanine aminotransferase (ALT), total bilirubin (T-bil), blood urea nitrogen (BUN), creatinine (Cr) and a decreased platelet count were significantly correlated with death within 1 week in a training cohort. Our formulated Objective Predictive Score was able to predict death within 1 week with high accuracy in a training and a validation cohort. CONCLUSION: Our scoring system might enable the assessment of prognostication with higher accuracy in a terminal care setting.

Androgen deprivation induces phenotypic plasticity and promotes resistance to molecular targeted therapy in a PTEN-deficient mouse model of prostate cancer.

Castration-resistant prostate cancer is an incurable heterogeneous disease that is characterized by a complex multistep process involving different cellular and biochemical changes brought on by genetic and epigenetic alterations. These changes lead to the activation or overexpression of key survival pathways that also serve as potential therapeutic targets. Despite promising preclinical results, molecular targeted therapies aimed at such signaling pathways have so far been dismal. In the present study, we used a PTEN-deficient mouse model of prostate cancer to show that plasticity in castration-resistant tumors promotes therapeutic escape. Unlike castration-naïve tumors which depend on androgen receptor and PI3K/AKT signal activation for growth and survival, castration-resistant tumors undergo phenotypic plasticity leading to increased intratumoral heterogeneity. These tumors attain highly heterogeneous phenotypes that are characterized by cancer cells relying on alternate signal transduction pathways for growth and survival, such as mitogen-activated protein kinase and janus kinase/signal transducer and activator of transcription, and losing their dependence on PI3K signaling. These features thus enabled castration-resistant tumors to become insensitive to the therapeutic effects of PI3K/AKT targeted therapy. Overall, our findings provide evidence that androgen deprivation drives phenotypic plasticity in prostate cancer cells and implicate it as a crucial contributor to therapeutic resistance in castration-resistant prostate cancer. Therefore, incorporating intratumoral heterogeneity in a dynamic tumor model as a part of preclinical efficacy determination could improve prediction for response and provide better rationale for the development of more effective therapies.

A new molecular targeted therapeutic approach for renal cell carcinoma with a p16 functional peptide using a novel transporter system.

Molecular targeting agents have become formidable anticancer weapons showing much promise against refractory tumors and functional peptides and are among the more desirable of these nanobio-tools. Intracellular delivery of multiple functional peptides forms the basis for a potent, non-invasive mode of delivery, providing distinctive therapeutic advantages. We examine the growth suppression efficiency of human renal cell carcinoma (RCC) by single-peptide targeting. We simultaneously introduced p16INK4a tumor suppressor peptides by Wr-T-mediated peptide delivery. Wr-T-mediated transport of p16INK4a functional peptide into 10 RCC lines, lacking expression of the p16INK4a molecule, reversed the specific loss of p16 function, thereby drastically inhibiting tumor growth in all but 3 lines by >95% within the first 96 h. In vivo analysis using SK-RC-7 RCC xenografts in nude mice demonstrated tumor growth inhibition by the p16INK4a peptide alone, however, inoculation of Wr-T and the p16INK4a functional peptide mixture, via the heart resulted in complete tumor regression. Thus, restoration of tumor suppressor function with Wr-T peptide delivery represents a powerful approach, with mechanistic implications for the development of efficacious molecular targeting therapeutics against intractable RCC.

Dual targeting of Bcl-2 and VEGF: a potential strategy to improve therapy for prostate cancer.

We previously demonstrated that Bcl-2 overexpression stimulates angiogenesis in PC-3 human prostate cancer cells, thus giving these tumors a growth advantage. To further elucidate the relationship between Bcl-2 and vascular endothelial growth factor (VEGF) in PC-3-Bcl-2 cells, tumorigenicity and angiogenesis were evaluated in our in vitro and in vivo model treated with antisense Bcl-2 oligodeoxynucleotide (ASO) and bevacizumab. In vitro and in vivo angiogenesis assays, as well as a xenograft tumor model of the human prostate cancer cell line PC-3-Bcl-2, were subjected to ASO alone, bevacizumab alone, or the combination of ASO and bevacizumab. Protein-based assays (e.g., immunohistochemical staining and enzyme-linked immunosorbent assay [ELISA]) were utilized to detect molecular changes. Interestingly, targeting Bcl-2 with ASO resulted in the inhibition of in vitro tube formation and inhibition of angiogenesis in Matrigel plugs similar to treatment with bevacizumab. In our PC-3-Bcl-2 xenograft model, ASO alone resulted in 41% reduction in tumor size, bevacizumab alone resulted in a 50% reduction in tumor size, whereas the combination of ASO with bevacizumab was associated with >95% reduction in tumor volume. Reduction in tumor size in all groups was associated with reduction in Bcl-2 and VEGF expression, induction of apoptosis, and inhibition of angiogenesis and its associated chemokine production. These findings confirm that Bcl-2 is a pivotal target for cancer therapy and thus, further study of this novel combination of Bcl-2 reduction and angiogenic targeting in human tumors is warranted.

Role of syndecan-1 (CD138) in cell survival of human urothelial carcinoma.

Heparan sulfate proteoglycan syndecan-1, CD138, is well known to be associated with cell proliferation, adhesion, and migration in various types of malignancies. In the present study, we focused on the role of syndecan-1 in human urothelial carcinoma of the urinary bladder. Silencing of syndecan-1 by siRNA transfection down-regulated transcriptional factor junB and the long isoform of FLICE-inhibitory protein (FLIP long), resulting in the induction of apoptosis in the urothelial carcinoma cell lines UMUC2 and UMUC3. Knockdown of junB and FLIP long as well as syndecan-1 silencing mediated apoptosis that was inhibited by pan-caspase inhibitors. Transurethral injection of syndecan-1 siRNA into the urinary bladder significantly reduced syndecan-1 gene expression and growth of red fluorescent-labeled KU-7/RFP bladder cancer cells in the mouse orthotopic bladder cancer model. Immunohistochemical examination showed high syndecan-1 protein expression in high-grade, superficial, and deep invasive carcinomas (pT1 and >or=pT2) as well as carcinoma in situ, but not in low-grade and noninvasive phenotypes (pTa). In addition, the percentage of cancer cells positive for syndecan-1 at initial diagnosis was statistically associated with the frequency of bladder cancer recurrence after transurethral resection. In conclusion, syndecan-1 might contribute to urothelial carcinoma cell survival and progression; therefore, this molecule could be a new therapeutic target in human urinary bladder cancer.

Syndecan-1, a new target molecule involved in progression of androgen-independent prostate cancer.

Heparan sulfate proteoglycan syndecan-1 (CD138) is well known to be associated with cell proliferation, adhesion and migration in various types of malignancies. In the present study, we focused on the role of syndecan-1 in human prostate cancer. Immunohistochemical analysis revealed either no or rare expression of syndecan-1 in normal secretory glands and prostate cancer cells at hormone naïve status, whereas the expression was significantly increased in viable cancer cells following neo-adjuvant hormonal therapy. Syndecan-1 expression was much higher in the androgen independent prostate cancer cell lines DU145 and PC3, rather than the androgen-dependent LNCaP, but the level in LNCaP was up-regulated in response to long-term culture under androgen deprivation. Silencing of syndecan-1 by siRNA transfection reduced endogenous production of reactive oxygen species through down-regulating NADPH oxidase 2 and induced apoptosis in DU145 and PC3 cells. Consistently, NADPH oxidase 2 knockdown induced apoptosis to a similar extent. Subcutaneous inoculation of PC3 cells in nude mice demonstrated the reduction of tumor size by localized injection of syndecan-1 siRNA in the presence of atelocollagen. Moreover, the mouse model and chorioallantoic membrane assay demonstrated significant inhibition of vascular endothelial growth factor and tumor angiogenesis by silencing of syndecan-1. In conclusion, syndecan-1 might participate in the process of androgen-dependent to -independent conversion, and be a new target molecule for hormone resistant prostate cancer therapy.

A novel human AlkB homologue, ALKBH8, contributes to human bladder cancer progression.

We recently identified a novel human AlkB homologue, ALKBH8, which is expressed in various types of human cancers including human urothelial carcinomas. In examining the role and function of ALKBH8 in human bladder cancer development in vitro, we found that silencing of ALKBH8 through small interfering RNA transfection reduced reactive oxygen species (ROS) production via down-regulation of NAD(P)H oxidase-1 (NOX-1) and induced apoptosis through subsequent activation of c-jun NH(2)-terminal kinase (JNK) and p38. However, we also found that JNK and p38 activation resulted in phosphorylation of H2AX (gammaH2AX), a variant of mammalian histone H2A, which contributes to the apoptosis induced by silencing ALKBH8 and NOX-1. Silencing of ALKBH8 significantly suppressed invasion, angiogenesis, and growth of bladder cancers in vivo as assessed both in the chorioallantoic membrane assay and in an orthotopic mouse model using green fluorescent protein-labeled KU7 human urothelial carcinoma cells. Immunohistochemical examination showed high expression of ALKBH8 and NOX-1 proteins in high-grade, superficially and deeply invasive carcinomas (pT(1) and >pT(2)) as well as in carcinoma in situ, but not in low-grade and noninvasive phenotypes (pT(a)). These findings indicate an essential role for ALKBH8 in urothelial carcinoma cell survival mediated by NOX-1-dependent ROS signals, further suggesting new therapeutic strategies in human bladder cancer by inducing JNK/p38/gammaH2AX-mediated cell death by silencing of ALKBH8.

Technical acquisition and dosimetric assessment of iodine-125 permanent brachytherapy in localized prostate cancer: our first series of 100 patients.

OBJECTIVES: To assess our initial experience in the treatment of localized prostate cancer using low-dose-rate brachytherapy (LDR-brachytherapy) with iodine-125. METHODS: One-hundred consecutive patients received LDR-brachytherapy between July 2004 and October 2006. Seventy-six patients were treated with seed implantation alone, whereas 24 patients were treated with a combination of brachytherapy and external beam radiotherapy. The minimal percentage of the dose received by 90% of the prostate gland (%D90), the percentage prostate volume receiving 100% of the prescribed minimal peripheral dose (V100), and the operation time were compared among every 10 consecutive patients. RESULTS: The means of %D90 and V100 were 109.6% and 93.4%, respectively. When compared with the first 10 patients, both D90 and V100 showed significant improvement in the following 10 consecutive patients. Similarly, the mean operation time decreased significantly according to the accumulated number of patients. CONCLUSIONS: Our initial experience with the first 100 cases suggests that LDR-brachytherapy needs accumulation of many more patients to obtain high-quality post-implant dosimetric outcomes.

PTEN knockout prostate cancer as a model for experimental immunotherapy.

PURPOSE: Testing immunotherapeutic strategies for prostate cancer has been impeded by the lack of relevant tumor models in immunocompetent animals. This opportunity is now provided by the recent development of prostate specific PTEN knockout mice, which show spontaneous development of true adenocarcinoma arising from prostate epithelium and more faithfully recapitulate the human disease than any previous model. We investigated the feasibility of using tumor cells derived from this model to test tumor vaccination and adoptive immunotherapeutic strategies for prostate cancer. MATERIALS AND METHODS: PTEN-CaP8 adenocarcinoma cells derived from the biallelic PTEN knockout prostate cancer model were used to vaccinate nontumor bearing litter mates. Tumor specific effector cells were generated from splenocytes of vaccinated mice by mixed lymphocyte-tumor reactions, and antiproliferative effects and cytokine generation were examined in vitro. The effect of vaccination or adoptive immunotherapy on luciferase marked PTEN-CaP8 subcutaneous tumors was monitored by tumor volumetric measurements and noninvasive bioluminescence imaging. RESULTS: Vaccination of litter mate mice with irradiated PTEN-CaP8 cells showed a significant prophylactic effect against the subsequent tumor challenge. Effector cells harvested from vaccinated litter mates showed significant interferon-gamma secretion upon co-incubation with PTEN-CaP8 target cells and they were capable of efficient target cell growth inhibition in vitro. Intratumor adoptive transfer of effector cells resulted in significant growth inhibition of preestablished prostate tumors in vivo. CONCLUSIONS: The PTEN knockout model serves as a highly useful model in which to investigate tumor cell vaccination and adoptive immunotherapeutic strategies in the context of true adenocarcinoma of the prostate. This model should accelerate efforts to develop effective immunotherapies for human prostate cancer.

GFP image analysis in the mouse orthotopic bladder cancer model.

Precise and objective measurements of tumor response have yet to be standardized in the mouse orthotopic bladder cancer model. In this study, we used image analysis and green fluorescent protein (GFP) to objectively measure tumor size in response to chemotherapy. KU-7 human bladder cancer cells transfected with GFP were intravesically inoculated into 8-week-old female nude mice. Fourteen days after tumor cell inoculation, the mice were assigned into a control (PBS) group or a doxorubicin (conc. 1.0 mg/ml) treatment group and received a single instillation of treatment. Fourteen days after treatment, the bladders were surgically exposed and fluorescent images were captured and later analyzed using image analysis. Bladders were processed for histological examination. Tumor incidence determined by GFP expression and histology was 100 and 80%, respectively, in the doxorubicin treatment group. A 9-fold (histology) vs. 12-fold (GFP expression) difference in tumor regression measured by tumor area (P<0.05) and a 5-fold (histology) vs. 9-fold (GFP expression) difference in tumor regression measured by the percent of tumor area in the bladder (P<0.001) were observed in the doxorubicin treatment group. Our findings suggest that using image analysis provides a precise, sensitive and objective means to measure tumor growth and treatment response in the mouse orthotopic bladder cancer model in lieu of histological methods. Consequently, the number of mice required in an experiment can be reduced since tissue samples are not needed for histology, thus making tissue samples readily available for additional assays in both a labor-effective and cost-effective manner.

Delivery of PTEN via a novel gene microcapsule sensitizes prostate cancer cells to irradiation.

The tumor suppressor gene MMAC/PTEN located on chromosome10q23.3 has dual phosphatase activity in the phosphoinositide-3-kinase signaling pathway and inhibits Akt activation, a serine-threonine kinase, which is involved in proliferative and antiapoptotic pathways. Furthermore, MMAC/PTEN is frequently inactivated in a variety of tumors including prostate cancer. In this study, we generated a new type of gene transfer drug, GelaTen, which is a microsphere of cationized gelatin hydrogels incorporating PTEN plasmid DNA. Using our previously reported radiation-resistant PC3-Bcl-2 human prostate cancer cells (PTEN deleted), we examined the efficacy of GelaTen to force the expression of PTEN in vivo to inhibit tumor growth after intratumoral injection alone or with irradiation. Combinational therapy with GelaTen and irradiation improved both the in vitro and in vivo efficacy of growth inhibition compared with GelaTen or irradiation alone. These data show that GelaTen gene therapy, enabling radiosensitization, can potentially treat prostate cancers that have MMAC/PTEN gene alterations associated with radioresistance.

c-Jun NH2 terminal kinase activation and decreased expression of mitogen-activated protein kinase phosphatase-1 play important roles in invasion and angiogenesis of urothelial carcinomas.

We here examined whether c-Jun NH(2) terminal kinase (JNK) might be involved in the progression of urothelial carcinomas. In vitro and in vivo invasion assays using Matrigel and chick embryo chorioallantoic membrane approaches showed constitutive activation of JNK to significantly increase two processes, invasion and angiogenesis, in the human urothelial carcinoma cell line kU-7, this being suppressed by a JNK inhibitor, SP600125, or cell-permeable peptides. In addition, we found that mitogen-activated protein kinase phosphatase (MKP)-1 functions as an endogenous inhibitor of JNK-mediated signals in urothelial carcinoma cells: chorioallantoic membrane assays showed UMUC14 cells with low MKP-1 expression to be more invasive and have pronounced angiogenesis compared to UMUC6 cells with high MKP-1. Furthermore, knockdown of the MKP-1 gene by siRNA transfection enhanced JNK activation in UMUC6 cells to the UMUC14 level. Immunohistochemically, JNK was found to be highly phosphorylated in high-grade and invasive carcinomas (>/=pT2) as well as carcinoma in situ but not in low-grade and noninvasive phenotypes (pTa, pT1). In contrast, MKP-1 was much more expressed in low-grade/noninvasive cancers than with the high-grade/invasive phenotype, reversely correlating with phosphorylated JNK. Taken together, JNK activation and decreased expression of MKP-1 may play important roles in progression of urothelial carcinoma.

Increased expression of cyclooxygenase-2 correlates with resistance to radiation in human prostate adenocarcinoma cells.

PURPOSE: Cyclooxygenase-2 functions as a survival factor by protecting cells from apoptosis. We analyzed cyclooxygenase-2 expression in LNCaP-COX-2 and LNCaP-Neo cell lines treated with irradiation. MATERIALS AND METHODS: LNCaP-COX-2 and LNCaP-Neo cells were treated with 0 to 500 microM celecoxib and a dose response curve was generated. A clonogenic assay was performed in which cells were subjected to irradiation (0 to 6 Gy) with or without celecoxib. Cyclooxygenase-2 protein and other relevant proteins were measured by immunohistochemistry Western blot analysis after irradiation and celecoxib treatment. RESULTS: The 2 studied cell lines experienced cytotoxic effects of celecoxib in a dose related manner. Clonogenic assays demonstrated that LNCaP-COX-2 cells were significantly more resistant to radiation therapy than LNCaP-Neo cells. Furthermore, the addition of celecoxib sensitized LNCaP-Neo and LNCaP-COX-2 cells to the cytocidal effects of radiation. Moreover, cyclooxygenase-2 over expression was associated with the over expression of pAkt and carbonic anhydrase. In this cell line irradiation alone was associated with increased expression of cyclooxygenase-2 and carbonic anhydrase. Combination therapy with irradiation and celecoxib down-regulated cyclooxygenase-2, pAKT and carbonic anhydrase. LNCaP-Neo cells expressed carbonic anhydrase and pAkt. Irradiation of these cells increased carbonic anhydrase and pAkt expression. Combination therapy with irradiation and celecoxib down-regulated carbonic anhydrase and pAkt. CONCLUSIONS: Cyclooxygenase-2 expression is also associated with pAkt and carbonic anhydrase expression. Down-regulation of cyclooxygenase-2 by celecoxib is associated with decreased expression of cyclooxygenase-2, pAkt and carbonic anhydrase, and eventual radiation sensitization, which is a phenomenon that may have clinical usefulness.