Omega-3 Fatty Acids for Depression in the Elderly and Patients with Dementia: A Systematic Review and Meta-Analysis.

This study aimed to evaluate the efficacy of omega-3 fatty acid supplementation interventions in improving depression in patients with dementia. To achieve this objective, randomized controlled trials (RCTs) were identified from primary electronic databases, focusing on the relationship between omega-3 fatty acids and depression in patients with dementia. The primary outcome was the impact of omega-3 fatty acids on post-intervention depression in patients with dementia, with subgroup analyses conducted based on the type of intervention (docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) combination), duration of intervention (3 months, 6 months, 12 months, ≥24 months), cognitive function (ranging from mild cognitive impairment (MCI) to severe dementia), and daily dosage (high, medium, low, applicable to both DHA and EPA). The study has been duly registered with PROSPERO (registration ID: CRD42023408744). A meta-analysis of five studies (n = 517) included in nine systematic reviews showed that omega-3 supplementation had a non-significant trend toward affecting depressive symptoms in patients with dementia (standardized mean difference (SMD): 0.147; 95% confidence interval (CI): -0.324 to 0.049; p = 0.141). Subgroup analyses revealed that DHA supplementation significantly reduced depressive symptoms (SMD: -0.247; p = 0.039). There was no significant effect for high (SMD: -0.169; 95% CI: -0.454 to 0.116; p = 0.246) or medium (SMD: -0.061; 95% CI: -0.228 to 0.105; p = 0.470) doses of EPA. However, low doses of EPA were significantly effective (SMD: -0.953; 95% CI: -1.534 to -0.373; p = 0.001), with notable improvements in patients with MCI (SMD: -0.934; p < 0.001). The study concludes that omega-3 fatty acids, particularly through DHA supplementation, may alleviate depressive symptoms in patients with MCI. Given the limited sample size, further long-term RCTs are recommended to better understand the efficacy and optimal management of omega-3 supplementation in this population using different dosages.

Tea polyphenol epigallocatechin-3-gallate inhibits cell proliferation in a patient-derived triple-negative breast cancer xenograft mouse model via inhibition of proline-dehydrogenase-induced effects.

Triple-negative breast cancers (TNBCs) lack specific targeted therapy options and have evolved into highly chemo-resistant tumors that metastasize to multiple organs. The present study demonstrated that the proline dehydrogenase (PRODH) mRNA level in paired (tumor vs. normal) human breast tissue samples (n=234) was 6.6-fold greater than normal cells (*p=0.021). We established stable PRODH-overexpressing TNBC (HS578T) cells, and the malignant phenotypes were evaluated using soft agar colony formation and Transwell migration assays. The results demonstrated that PRODH induced epithelial-mesenchymal transition in cancer cells and increased cell proliferation. The present study found that the tea polyphenol epigallocatechin-3-gallate (EGCG) significantly inhibited PRODH and its regulated proteins, such as alpha-smooth muscle actin (alpha-SMA) expression in TNBC cells. These findings support the targeting of the PRODH signaling pathway as a potential therapeutic strategy in preventing cancer cell metastasis. The patient-derived xenograft (PDX) mouse model is highly relevant to real human tumor growth. We established a TNBC-PDX (F4, n=4 in each group)mouse model. The PDX mice were treated with EGCG (50 mg/kg), and the results indicated that EGCG significantly inhibited PDX tumor growth (*p = 0.013). These experiments provide additional evidence to evaluate the antitumor effects of EGCG-induced PRODH inhibition for clinical therapeutic application, especially in TNBC patients.

A Phase II Clinical Trial on the Combination Therapy of PHY906 Plus Capecitabine in Hepatocellular Carcinoma.

LESSONS LEARNED: A PHY906 and capecitabine combination could be effective as a salvage therapy for patients with hepatocellular carcinoma (HCC) previously treated with multiple systemic therapies. This traditional Chinese medicine formulation can work with Western cancer chemotherapeutic agents to improve clinical outcomes or alleviate side effects for patients with advanced HCC. BACKGROUND: This study aimed to evaluate efficacy and safety of capecitabine combined with a PHY906 (a pharmaceutical-grade formulation of four traditional Chinese herbs) in the treatment of advanced hepatocellular carcinoma (HCC) in Asian patients who were positive for hepatitis B virus (HBV). METHODS: This study was an open-label, phase II safety and efficacy clinical trial of PHY906 and capecitabine in patients with advanced HCC. Patients received 750 mg/m2 capecitabine b.i.d. 14 days plus 800 mg of PHY906 b.i.d. on days 1-4 and days 8-11 every 21-day cycle. The primary endpoint was 6-month survival rate, and secondary endpoints were progression-free survival, overall survival, disease control rate, and safety. RESULTS: Thirty-nine subjects completed the study with a 46.2% stable disease rate. The median progression-free survival was 1.5 months, and median overall survival (mOS) was 6 months with a 51.3% 6-month survival rate. The most common adverse events included lower hemoglobin, diarrhea, pain, abdomen (not otherwise specified), fatigue, increased aspartate aminotransferase, and bilirubin. Patients who (a) had not received previous chemotherapies or targeted therapy or (b) had lower starting alpha-fetoprotein (AFP) levels or (c) had HBV infection showed better clinical outcome. CONCLUSION: Our data showed that PHY906 increases the therapeutic index of capecitabine by enhancing its antitumor activity and reduces its toxicity profile in advanced HCC.

Astragalus membranaceus-Derived Anti-Programmed Death-1 Monoclonal Antibodies with Immunomodulatory Therapeutic Effects against Tumors.

Astragalus membranaceus polysaccharide (APS) components are main ingredients of TCM and have proven efficacy to activate T cells and B cells, enhancing immunity in humans. In this study, elevated cytokine and anti-PD-1 antibody titers were found in mice after immunization with APS. Therefore, phage-display technology was utilized to isolate specific anti-programmed death-1 (PD-1) antibodies from mice stimulated by APS and to confirm whether the isolated anti-PD-1 antibody could inhibit the interaction of PD-1 with the programmed death-ligand 1 (PD-L1), resulting in tumor growth inhibition. The isolated single-chain fragment variable (scFv) S12 exhibited the highest binding affinity of 20 nM to PD-1, completed the interaction between PD-1 and PD-L1, and blocked the effect of PD-L1-induced T cell exhaustion in peripheral blood mononuclear cells in vitro. In the animal model, the tumor growth inhibition effect after scFv S12 treatment was approximately 48%. However, meaningful synergistic effects were not observed when scFv S12 was used as a cotreatment with ixabepilone. Moreover, this treatment caused a reduction in the number of tumor-associated macrophages in the tumor tissue. These experimental results indirectly indicate the ability of APS to induce specific antibodies associated with the immune checkpoint system and the potential benefits for improving immunity in humans.

A phase I trial of escalating doses of cixutumumab (IMC-A12) and sorafenib in the treatment of advanced hepatocellular carcinoma.

PURPOSE: The insulin-like growth factor (IGF) pathway is activated in hepatocarcinogenesis. Cixutumumab is a monoclonal antibody against human insulin-like growth factor-1 receptor (IGF-1R). Given the cross-talk between the IGF and VEGF pathways, we performed a phase I study of the combination of cixutumumab and sorafenib in hepatocellular cancer (HCC). METHODS: Eligible patients with no prior systemic therapy for advanced HCC and Child-Pugh A to B7 were treated with sorafenib 400 mg BID and escalating doses of cixutumumab (2, 4, or 6 mg/kg IV weekly) in a 3 + 3 design. Dose limiting toxicity (DLT) was defined as treatment-related grade 3 or 4 non-hematologic toxicity (except for a subset of manageable toxicities) or any grade 4 hematologic toxicities. RESULTS: In 21 patients enrolled, there were 3 DLTs; grade 3 hyperglycemia, grade 3 hypophosphatemia, and grade 5 peritonitis. The maximum tolerated dose of cixutumumab was 4 mg/kg IV weekly with standard dose sorafenib. Eighteen of 21 (86%) patients had grade 3 or above toxicities attributed to treatment. One patient also experienced grade 4 colonic perforation and grade 5 peritonitis. The median number of cycles completed was 4 (0-26). Of 16 patients evaluable for response, 81% achieved stable disease. The median progression free survival was 6.0 months (95% CI 3.6-undefined) and the median overall survival was 10.5 months (95% CI 7.1-undefined). CONCLUSIONS: While the combination of cixutumumab and sorafenib had a toxicity profile similar to that of sorafenib monotherapy, it manifested limited clinical efficacy in unselected patients with HCC.

Dual Inhibition of PIK3C3 and FGFR as a New Therapeutic Approach to Treat Bladder Cancer.

Purpose: MPT0L145 has been developed as a FGFR inhibitor exhibiting significant anti-bladder cancer activity in vitro and in vivo via promoting autophagy-dependent cell death. Here, we aim to elucidate the underlying mechanisms.Experimental Design: Autophagy flux, morphology, and intracellular organelles were evaluated by Western blotting, transmission electron microscope, and fluorescence microscope. Molecular docking and surface plasmon resonance assay were performed to identify drug-protein interaction. Lentiviral delivery of cDNA or shRNA and CRISPR/Cas9-mediated genome editing was used to modulate gene expression. Mitochondrial oxygen consumption rate was measured by a Seahorse XFe24 extracellular flux analyzer, and ROS level was measured by flow cytometry.Results: MPT0L145 persistently increased incomplete autophagy and phase-lucent vacuoles at the perinuclear region, which were identified as enlarged and alkalinized late-endosomes. Screening of a panel of lipid kinases revealed that MPT0L145 strongly inhibits PIK3C3 with a Kd value of 0.53 nmol/L. Ectopic expression of PIK3C3 reversed MPT0L145-increased cell death and incomplete autophagy. Four residues (Y670, F684, I760, D761) at the ATP-binding site of PIK3C3 are important for the binding of MPT0L145. In addition, MPT0L145 promotes mitochondrial dysfunction, ROS production, and DNA damage, which may in part, contribute to cell death. ATG5-knockout rescued MPT0L145-induced cell death, suggesting simultaneous induction of autophagy is crucial to its anticancer activity. Finally, our data demonstrated that MPT0L145 is able to overcome cisplatin resistance in bladder cancer cells.Conclusions: MPT0L145 is a first-in-class PIK3C3/FGFR inhibitor, providing an innovative strategy to design new compounds that increase autophagy, but simultaneously perturb its process to promote bladder cancer cell death. Clin Cancer Res; 24(5); 1176-89. ©2017 AACR.

Pu-erh Tea Extract Attenuates Nicotine-Induced Foam Cell Formation in Primary Cultured Monocytes: An in Vitro Mechanistic Study.

In this study, the mechanisms by which pu-erh tea extract (PETE) attenuates nicotine-induced foam cell formation were investigated. Monocytes were purified from healthy individuals using commercial antibodies coated with magnetic beads. We found that the nicotine-induced (1-10 µM) expression of oxidized low-density lipoprotein receptors (ox-LDLRs) and α9-nAchRs in monocytes was significantly attenuated by 24 h of PETE (10 µg/mL; ∗, p < 0.05) cotreatment. Nicotine (1 µM for 24 h) significantly induced the expression of the surface adhesion molecule ICAM-1 and the monocyte integrin adhesion molecule (CD11b) by human umbilical vein endothelial cells (HUVECs) and triggered monocytes to differentiate into macrophages via interactions with the endothelium. After treatment with nicotine (0.1-10 µM for 24 h), the HUVECs released chemotactic factors (IL-8) to attract monocytes into the tunica intima of the artery, and the monocytes then transformed into foam cells. We demonstrated that PETE treatment (>1 µg/mL for 24 h; ∗, p < 0.05) significantly attenuates nicotine-induced (1 µM) monocyte migration toward HUVECs and foam cell formation. This study suggests that tea components effectively attenuate the initial step (foam cell formation) of nicotine-induced atherosclerosis in circulating monocytes.

PHY906(KD018), an adjuvant based on a 1800-year-old Chinese medicine, enhanced the anti-tumor activity of Sorafenib by changing the tumor microenvironment.

PHY906 (KD018) is a four-herb Chinese Medicine Formula. It has been shown to potentially enhance the therapeutic indices of different class anticancer agents in vivo. Here, PHY906 is reported to enhance the anti-tumor activity of Sorafenib in nude mice bearing HepG2 xenografts. Among the four herbal ingredients of PHY906, Scutellaria baicalensis Georgi (S) and Paeonia lactiflora Pall (P) are required; however, S plays a more important role than P in increasing tumor apoptosis induced by Sorafenib with an increase of mouse(m)FasL and human(h)FasR expression. PHY906 may potentiate Sorafenib action by increasing hMCP1 expression and enhancing infiltration of macrophages into tumors with a higher M1/M2 (tumor rejection) signature expression pattern, as well as affect autophagy by increasing AMPKα-P and ULK1-S555-P of tumors. Depletion of macrophage could counteract PHY906 to potentiate the anti-tumor activity of Sorafenib. It was reported that tumor cells with higher levels of ERK1/2-P are more susceptible to Sorafenib, and the S component of PHY906 may increase ERK1/2-P via inhibition of ERK1/2 phosphatase in HepG2 tumors. PHY906 may potentiate the anti-hepatoma activity of Sorafenib by multiple mechanisms targeting on the inflammatory state of microenvironment of tumor tissue through two major ingredients (P and S) of PHY906.

Plasma polyunsaturated fatty acids and periodontal recovery in Taiwanese with periodontitis: a significant relationship.

BACKGROUND: Plasma levels of polyunsaturated fatty acids (PUFAs) are different before and after periodontal treatment. Asians and Westerners have significantly different baseline levels of plasma PUFAs. However, no Asian study has reported the effects of nonsurgical treatment on the correlation between periodontal condition and plasma levels of PUFAs. We analyzed whether recovery from periodontitis was correlated with the elevation of plasma fatty acids 3 months after the nonsurgical intervention and with no recommended supplements. DESIGN: Thirty-five Taiwanese patients with periodontitis were recruited. Probing pocket depths (PPDs) and clinical attachment levels (CALs) were measured at baseline and 3 months after the nonsurgical treatment. Plasma levels of fatty acids were determined using gas chromatography. Differences and correlations between plasma fatty acid composition and periodontitis severity at baseline and 3 months after treatment were determined. RESULTS: Twenty-six patients completed the study. At the baseline, PPDs were negatively correlated with plasma n-3 PUFAs (r=-0.52, p<0.01), but at 3 months post intervention, periodontitis severity had declined and the weight percentages of n-3 PUFAs, DPA, and DHA were significantly (p=0.019, 0.005, and 0.037, respectively) higher. The recovery percentages of CALs were positively and significantly correlated with plasma ΔPUFAs and the percentage of Δn-3 PUFAs in ΔPUFAs (r=0.42 and 0.45, respectively; p<0.05 for both). CONCLUSIONS: We conclude that a higher weight percentage of n-3 PUFAs in total PUFAs was related to the recovery of CALs 3 months after the nonsurgical periodontal treatment. However, no such relationship was found for PPDs.

A distinct metabolic signature of human colorectal cancer with prognostic potential.

PURPOSE: Metabolic phenotyping has provided important biomarker findings, which, unfortunately, are rarely replicated across different sample sets due to the variations from different analytical and clinical protocols used in the studies. To date, very few metabolic hallmarks in a given cancer type have been confirmed and validated by use of a metabolomic approach and other clinical modalities. Here, we report a metabolomics study to identify potential metabolite biomarkers of colorectal cancer with potential theranostic value. EXPERIMENTAL DESIGN: Gas chromatography-time-of-flight mass spectrometry (GC-TOFMS)-based metabolomics was used to analyze 376 surgical specimens, which were collected from four independent cohorts of patients with colorectal cancer at three hospitals located in China and City of Hope Comprehensive Cancer Center in the United States. Differential metabolites were identified and evaluated as potential prognostic markers. A targeted transcriptomic analysis of 29 colorectal cancer and 27 adjacent nontumor tissues was applied to analyze the gene expression levels for key enzymes associated with these shared metabolites. RESULTS: A panel of 15 significantly altered metabolites was identified, which demonstrates the ability to predict the rate of recurrence and survival for patients after surgery and chemotherapy. The targeted transcriptomic analysis suggests that the differential expression of these metabolites is due to robust metabolic adaptations in cancer cells to increased oxidative stress as well as demand for energy, and macromolecular substrates for cell growth and proliferation. CONCLUSIONS: These patients with colorectal cancer, despite their varied genetic background, mutations, pathologic stages, and geographic locations, shared a metabolic signature that is of great prognostic and therapeutic potential.

γ-H2AX kinetics as a novel approach to high content screening for small molecule radiosensitizers.

BACKGROUND: Persistence of γ-H2AX after ionizing radiation (IR) or drug therapy is a robust reporter of unrepaired DNA double strand breaks in treated cells. METHODS: DU-145 prostate cancer cells were treated with a chemical library ±IR and assayed for persistence of γ-H2AX using an automated 96-well immunocytochemistry assay at 4 hours after treatment. Hits that resulted in persistence of γ-H2AX foci were tested for effects on cell survival. The molecular targets of hits were validated by molecular, genetic and biochemical assays and in vivo activity was tested in a validated Drosophila cancer model. RESULTS: We identified 2 compounds, MS0019266 and MS0017509, which markedly increased persistence of γ-H2AX, apoptosis and radiosensitization in DU-145 cells. Chemical evaluation demonstrated that both compounds exhibited structurally similar and biochemical assays confirmed that these compounds inhibit ribonucleotide reductase. DNA microarray analysis and immunoblotting demonstrates that MS0019266 significantly decreased polo-like kinase 1 gene and protein expression. MS0019266 demonstrated in vivo antitumor activity without significant whole organism toxicity. CONCLUSIONS: MS0019266 and MS0017509 are promising compounds that may be candidates for further development as radiosensitizing compounds as inhibitors of ribonucleotide reductase.

Phase I/II study of PHY906/capecitabine in advanced hepatocellular carcinoma.

PHY906 is a Chinese medicine formula with claims for the treatment of severe gastrointestinal distress. PHY906 enhanced the therapeutic index of various chemotherapeutic agents in human hepatocellular carcinoma xenografts. Accordingly, here a phase I/II clinical study was conducted with the combination of capecitabine in patients with advanced, unresectable hepatocellular carcinoma. More than 60% of patients had either stable disease or better after two treatment cycles. Median overall survival was 9.2 months. Asian patients had a higher median overall survival (16.5 months) than non-Asian patients (6.2 months, p=0.03). Patients' quality of life did not deteriorate significantly during treatment. This finding supported further investigation of PHY906 as an adjuvant therapy of capecitabine in a larger hepatocellular cancer population.

In-chern-hau-tang and genipin reduces acute urinary bladder distension evoked sympathetic activation-induced hepatic dysfunction in rats.

Increased norepinephrine production by acute urine retention (AUR) induced sympathetic activation may contribute to acute liver injury (ALI) via the action of hepatic vasoconstriction and increased reactive oxygen species (ROS) production. We evaluated whether In-Chern-Hau-Tang, a hepatoprotective herb medicine, and its major ingredient genipin, may ameliorate norepinephrine-induced liver injury in the rat. We determined the effects of In-Chern-Hau-Tang and genipin on norepinephrine-induced oxidative stress in the Kupffer and endothelial cells and AUR-induced ALI in the rat via a chemiluminescence analyzer, physiologic and biochemical determination and western blot. The results of in vitro study showed that genipin with efficient H(2)O(2) and HOCl scavenging activities decreased norepinephrine-enhanced ROS production in the Kupffer cell and endothelial cell cultures. AUR activated hepatic sympathetic nervous activity lead to a hepatic hypoxia/hypoperfusion, and a reduction in bile flow. AUR increased intercellular adhesion molecular 1 (ICAM-1) protein expression, and hepatic ROS production from the activated leukocyte NADPH oxidase activity subsequently leading to plasma aspartate aminotransferase (AST) elevation. Hepatic sympathetic denervation, or oral pretreatment of In-Chern-Hau-Tang or genipin for 1 week ameliorated the level in AUR-induced hepatic hypoxia/hypoperfusion, and bile stasis. Hepatic denervation, In-Chern-Hau-Yang and genipin inhibited AUR-enhanced hepatic ICAM-1 expression, hepatic ROS production, leukocyte NADPH oxidase activity and plasma AST activity. In conclusion, In-Chern-Hau-Tang along with its active component, genipin, can ameliorate AUR-induced ALI via the alleviation of oxidative stress possibly by the inhibition of sympathetic induced hypoxia/hypoperfusion and leukocyte NADPH oxidase activity.

Phase I trial of GTI-2040, oxaliplatin, and capecitabine in the treatment of advanced metastatic solid tumors: a California Cancer Consortium Study.

BACKGROUND: GTI-2040 is a 20-mer antisense oligonucleotide targeting the mRNA of ribonucleotide reductase M2. It was combined with oxaliplatin and capecitabine in a phase I trial in patients with advance solid tumors based on previous studies demonstrating potentiation of chemotherapy with ribonucleotide reductase inhibitors. METHODS: Patients at least 18 years of age with advanced incurable solid tumors and normal organ function as well as a Karnofsky performance status of > or =60% were eligible. One prior chemotherapy regimen for advanced disease or relapse within 12 months of adjuvant chemotherapy was required. Patients could have received prior fluoropyrimidines, including capecitabine, but not oxaliplatin. Treatment cycles were 21 days. In each cycle, GTI-2040 was given as a continuous intravenous infusion over 14 days, oxaliplatin as a 2-h intravenous infusion on day 1, and capecitabine orally twice a day for 14 days. In cycle 1 only, oxaliplatin and capecitabine were started on day 2 to allow ribonucleotide reductase mRNA levels to be measured with and without oxaliplatin and capecitabine. Doses were escalated in cohorts of three patients using a standard 3 + 3 design until the maximum tolerated dose was established, defined as no more than one first-cycle dose-limiting toxicity among six patients treated at a given dose level. RESULTS: The maximum tolerated dose was estimated to be the combination of GTI-2040 3 mg/kg per day for 14 days, capecitabine 600 mg/m(2) twice daily for 14 days, and oxaliplatin 100 mg/m(2) every 21 days. Dose-limiting toxicities were hematologic. GTI-2040 pharmacokinetics, obtained at steady-state on days 7 and 14, showed the high inter-patient variability previously reported. Two of six patients had stable disease at the maximum tolerated dose and one patient, with heavily pre-treated non-small cell lung cancer, had a partial response at a higher dose level. In samples from a limited number of patients, there was no clear decrease in ribonucleotide reductase expression in peripheral blood mononuclear cells during treatment. CONCLUSION: A combination of GTI-2040, capecitabine and oxaliplatin is feasible in patients with advanced solid tumors.

Symptom concerns and quality of life in hepatobiliary cancers.

PURPOSE/OBJECTIVES: To describe the symptom concerns of patients with hepatocellular carcinoma (HCC) and pancreatic cancer and explore the effect of symptoms on patients' quality of life (QOL). DESIGN: Descriptive, longitudinal study. SETTING: Ambulatory clinics of a comprehensive cancer center. SAMPLE: 45 patients actively receiving treatment for either HCC or pancreatic cancer. METHODS: Patients were followed from baseline for three months, with outcome measures repeated monthly. Outcome measures included the Functional Assessment of Cancer Therapy-Hepatobiliary (FACT-Hep) and the Functional Assessment of Chronic Illness Therapy-Spirituality Subscale (FACIT-Sp-12). Descriptive analysis of demographic, treatment, and symptom data was conducted, followed by two-way repeated measures analysis of variance of FACT-Hep and FACIT-Sp-12 scale scores by diagnosis and treatment type. MAIN RESEARCH VARIABLES: Symptoms, QOL. FINDINGS: Overall QOL is poor in patients with hepatobiliary cancer, and this trend continues over time. Symptoms such as abdominal pain, fatigue, weight loss, and poor appetite commonly are reported in this population. CONCLUSIONS: Patients with hepatobiliary cancer suffer from multiple symptoms that may have a negative affect on overall QOL. Specific QOL domains, such as physical and functional well-being, are of particular concern for patients. IMPLICATIONS FOR NURSING: The identification of specific symptom and QOL concerns in hepatobiliary cancers will enhance clinical care and aid in the future development of multidisciplinary interventions for this understudied cancer population.

Annexin-I as a potential target for green tea extract induced actin remodeling.

Using a multistep human urothelial model, we previously showed that green tea extract (GTE) selectively modulates actin remodeling in transformed cells (MC-T11), which resulted in increased cell adhesion and reduced cell motility (Lu et al., Clin Cancer Res 2005;11:1675-83). This study further analyzed which actin binding proteins (ABPs) might be involved in this process. Proteomic profiles of GTE treated and untreated MC-T11 cells using two-dimensional gel electrophoresis coupled with liquid chromatography tandem mass spectrometry (LC/MS/MS) and matrix-assisted laser desorption and ionization time-of-flight (MALDI-TOF) identified 20 GTE-induced proteins. Among them, 3 were ABPs (tropomodulin, cofilin and annexin-I), and only annexin-I showed a dose- and time-dependent expression. The increased annexin-I correlated with actin remodeling, and was the result of transcription level up-regulation, as determined by RT-PCR, pull-down immunoblot and siRNA analyses. 5-Azacytidine, a DNA methylation inhibitor, exhibited no effect on annexin-I expression when used alone, but had an additive effect for GTE-induced annexin-I expression. Immunohistochemistry of bladder cancer tissue array showed a decrease of annexin-I expression in carcinoma in situ and low grade papillary carcinoma (n = 32, 0% positive) compared to nontumor urothelium (n = 18, 89% positive) (p < 0.001 by Fisher exact test), but increased in some (6 of 15, 40%) high-grade tumors. Together, GTE induced annexin-I expression plays a role in regulating actin remodeling and decreased annexin-I expression is a common event in early stage of bladder cancer development.

A Ferrous-Triapine complex mediates formation of reactive oxygen species that inactivate human ribonucleotide reductase.

Ribonucleotide reductase plays a central role in cell proliferation by supplying deoxyribonucleotide precursors for DNA synthesis and repair. The holoenzyme is a protein tetramer that features two large (hRRM1) and two small (hRRM2 or p53R2) subunits. The small subunit contains a di-iron cluster/tyrosyl radical cofactor that is essential for enzyme activity. Triapine (3-aminopyridine-2-carboxaldehyde thiosemicarbazone, 3-AP) is a new, potent ribonucleotide reductase inhibitor currently in phase II clinical trials for cancer chemotherapy. Ferric chloride readily reacts with Triapine to form an Fe(III)-(3-AP) complex, which is reduced to Fe(II)-(3-AP) by DTT. Spin-trapping experiments with 5,5-dimethyl-1-pyrroline-N-oxide prove that Fe(II)-(3-AP) reduces O2 to give oxygen reactive species (ROS). In vitro activity assays show that Fe(II)-(3-AP) is a much more potent inhibitor of hRRM2/hRRM1 and p53R2/hRRM1 than Triapine. Electron paramagnetic resonance measurements on frozen solutions of hRRM2 and p53R2 show that their tyrosyl radicals are completely quenched by incubation with Fe(II)-(3-AP). However, the enzyme activity is maintained in protein samples supplemented with catalase alone or in combination with superoxide dismutase. Furthermore, catalase alone or in combination with superoxide dismutase markedly decreases the antiproliferative effect of Triapine in cytotoxicity assays. These results indicate that Triapine-induced inhibition of ribonucleotide reductase is caused by ROS. We suggest that ROS may ultimately be responsible for the pharmacologic effects of Triapine in vivo.

Hypermethylation of growth arrest DNA damage-inducible gene 45 beta promoter in human hepatocellular carcinoma.

Growth arrest DNA damage-inducible gene 45 beta (GADD45beta) has been known to regulate cell growth, apoptotic cell death, and cellular response to DNA damage. Down-regulation of GADD45beta has been verified to be specific in hepatocellular cancer (HCC) and consistent with the p53 mutant, and degree of malignancy of HCC. This observation was further confirmed by eight HCC cell lines and paired human normal and HCC tumor tissues by Northern blot and immunohistochemistry. To better understand the transcription regulation, we cloned and characterized the active promoter region of GADD45beta in luciferase-expressing vector. Using the luciferase assay, three nuclear factor-kappaB binding sites, one E2F-1 binding site, and one putative inhibition region were identified in the proximal promoter of GADD45beta from -865/+6. Of interest, no marked putative binding sites could be identified in the inhibition region between -520/-470, which corresponds to CpG-rich region. The demethylating agent 5-Aza-dC was used and demonstrated restoration of the GADD45beta expression in HepG2 in a dose-dependent manner. The methylation status in the promoter was further examined in one normal liver cell, eight HCC cell lines, eight HCC tissues, and five corresponding nonneoplastic liver tissues. Methylation-specific polymerase chain reaction and sequencing of the sodium bisulfite-treated DNA from HCC cell lines and HCC samples revealed a high percentage of hypermethylation of the CpG islands. Comparatively, the five nonneoplastic correspondent liver tissues demonstrated very low levels of methylation. To further understand the functional role of GADD45beta under-expression in HCC the GADD45beta cDNA constructed plasmid was transfected into HepG2 (p53 WT) and Hep3B (p53 null) cells. The transforming growth factor-beta was assayed by enzyme-linked immunosorbent assay, which revealed a decrease to 40% in transfectant of HepG2, but no significant change in Hep3B transfectant. Whereas, Hep3B co-transfected with p53 and GADD45beta demonstrated significantly reduced transforming growth factor-beta. The colony formation was further examined and revealed a decrease in HepG2-GADD45beta transfectant and Hep3B-p53/GADD45beta co-transfectant. These findings suggested that methylation might play a crucial role in the epigenetic regulation of GADD45beta in hepatocyte transformation that may be directed by p53 status. Thus, our results provided a deeper understanding of the molecular mechanism of GADD45beta down-regulation in HCC.