Methionine redox regulation of actin-interacting proteins primarily governs antioxidative signaling and response to the salvianolic acid B treatment in EA.hy926 cells.

Actin-interacting proteins are important molecules for filament assembly and cytoskeletal signaling within vascular endothelium. Disruption in their interactions causes endothelial pathogenesis through redox imbalance. Actin filament redox regulation remains largely unexplored, in the context of pharmacological treatment. This work focused on the peptidyl methionine (M) redox regulation of actin-interacting proteins, aiming at elucidating its role on governing antioxidative signaling and response. Endothelial EA.hy926 cells were subjected to treatment with salvianolic acid B (Sal B) and tert-butyl-hydroperoxide (tBHP) stimulation. Mass spectrometry was employed to characterize redox status of proteins, including actin, myosin-9, kelch-like erythroid-derived cap-n-collar homology-associated protein 1 (Keap1), plastin-3, prelamin-A/C and vimentin. The protein redox landscape revealed distinct stoichiometric ratios or reaction site transitions mediated by M sulfoxide reductase and reactive oxygen species. In comparison with effects of tBHP stimulation, Sal B treatment prevented oxidation at actin M325, myosin-9 M1489/1565, Keap1 M120, plastin-3 M592, prelamin-A/C M187/371/540 and vimentin M344. For Keap1, reaction site was transitioned within its scaffolding region to the actin ring. These protein M oxidation regulations contributed to the Sal B cytoprotective effects on actin filament. Additionally, regarding the Keap1 homo-dimerization region, Sal B preventive roles against M120 oxidation acted as a primary signal driver to activate nuclear factor erythroid 2-related factor 2 (Nrf2). Transcriptional splicing of non-POU domain-containing octamer-binding protein was validated during the Sal B-mediated overexpression of NAD(P)H dehydrogenase [quinone] 1. This molecular redox regulation of actin-interacting proteins provided valuable insights into the phenolic structures of Sal B analogs, showing potential antioxidative effects on vascular endothelium.

Bidirectional crosstalk of the cAMP/ROS-dependent signaling pathways in inflammatory macrophage: An activation of formononetin.

Bacterial lipopolysaccharide (LPS) is a toxic stimulant to macrophage inflammation. Inflammation intersects cell metabolism and often directs host immunopathogenesis stress. We aim here at pharmacological discovering of formononetin (FMN) action, to which anti-inflammatory signaling spans across immune membrane receptors and second messenger metabolites. In ANA-1 macrophage stimulated by LPS, and simultaneous treatment with FMN, results show the Toll-like receptor 4 (TLR4) and estrogen receptor (ER) signals, in concert with reactive oxygen species (ROS) and cyclic adenosine monophosphate (cAMP), respectively. LPS stimulates inactivation of the ROS-dependent nuclear factor erythroid 2-related factor 2 (Nrf2) by upregulating TLR4, but it does not affect cAMP. However, FMN treatment not only activates Nrf2 signaling by TLR4 inhibition, but also it activates cAMP-dependent protein kinase activities by upregulating ER. The cAMP activity gives rise to phosphorylation (p-) of protein kinase A, liver kinase B1 and 5'-AMP activated protein kinase (AMPK). Moreover, bidirectional signal crosstalk is amplified between p-AMPK and ROS, as FMN combinational validation with AMPK activator/inhibitor/target small-interfering RNA or ROS scavenger. The signal crosstalk is well positioned serving as the 'plug-in' knot for rather long signaling axis, and the immune-to-metabolic circuit via ER/TLR4 signal transduction. Collectively, convergence of the FMN-activated signals drives significant reduction of cyclooxygenase-2, interleukin-6 and NLR family pyrin domain-containing protein 3, in LPS-stimulated cell. Although anti-inflammatory signaling is specifically related to the immune-type macrophage, the p-AMPK antagonizing effect arises from FMN combination with ROS scavenger H-bond donors. Information of our work assists in predictive traits against macrophage inflammatory challenges, using phytoestrogen discoveries.

More-Is-Better Strategy for Constructing Homoligand Polypyridyl Ruthenium Complexes as Photosensitizers for Infrared Two-Photon Photodynamic Therapy.

Photodynamic therapy (PDT) uses a combination of photosensitizers (PSs), light sources, and reactive oxygen species (ROS) to damage only the desired target and keep normal tissues from being hurt. The dark cytotoxicity (chemotoxicity) of PSs, leading to whole-body damage in the absence of irradiation, is a major limiting factor in PDT. How to simultaneously increase ROS generation and decrease dark cytotoxicity is an essential challenge that must be resolved in PS research. In this study, a series of homoligand polypyridyl ruthenium complexes (HPRCs) containing three singlet oxygen (1O2)-generating ligands (L) in a single molecule ([Ru(L)3]2+) have been constructed. Compared to the heteroligand complexes [Ru(bpy)2(L)]2+ where bpy is 2,2'-bipyridine, the 1O2 quantum yield under infrared two-photon irradiation and the DNA photocleavage effect of the HPRCs are significantly enhanced with two more ligands L. The intraligand triplet excited states transition played an important role in the activation of oxygen. The HPRCs target the mitochondria but not the nuclei, generating 1O2 intracellularly under irradiation of visible or infrared light. Ru1 exhibits high phototoxicity and low dark cytotoxicity toward human malignant melanoma cells in vitro. Moreover, HPRCs have minimal cytotoxicity to human normal liver cells, suggesting their potential as antitumor PDT reagents with more security. This study may provide inspiration for the structural design of potent PS for PDT.

Ultra-high hydrogen storage capacity of holey graphyne.

Holey graphyne (HGY), a novel two-dementional 2D single-crystalline carbon allotrope, was recently synthesized by Castro-Stephens coupling reaction. The naturally existing uniform periodic holes in the 2D carbon-carbon network demonstrate its promising potential in the energy storage. Herein, we conducted density functional theory (DFT) calculation to predict the hydrogen storage capacity of HGY sheet. It is found the Li-decorated single-layer HGY can serve as a promising candidate for hydrogen storage. Our DFT calculations demonstrate that Li atoms can bind strongly to the HGY sheet without the formation of Li clusters, and each Li atom can anchor four H2 molecules with the average adsorption energy about 0.22 eV/H2. The largest hydrogen storage capacity of the doped HGY sheet can reach as high as 12.8 wt%, largely surpassing the target of the U. S. DOE (9 wt%), showing the Li/HGY complex is an ideal hydrogen storage material at ambient conditions. In addition, we investigate the polarization mechanism of the storage media and find that the polarization is originated from both the electric field induced by the ionic Li decorated on the HGY and the weak polarized hydrogen molecules dominated the H2 adsorption process.

G protein pathway suppressor 2 (GPS2) acts as a tumor suppressor in liposarcoma.

Liposarcoma(LPS) is the most common type of soft tissue sarcoma accounting for 20 % of all adult sarcomas. However, the molecular pathogenesis of this malignancy is still poorly understood. Here, we showed that GPS2 expression was downregulated in LPS and correlated with the prognosis of this disease. In vitro study showed that knockdown of GPS2 resulted in enhanced proliferation and migration of LPS cell line SW872, without significant influence of cell death. Conclusively, our results suggest that GPS2 may act as a tumor suppressor in LPS and serve as a potential prognosis marker for this disease.

Bleeding the Excited State Energy to the Utmost: Single-Molecule Iridium Complexes for In Vivo Dual Photodynamic and Photothermal Therapy by an Infrared Low-Power Laser.

A series of cyclometalated Ir(III) complexes with morpholine and piperazine groups are designed as dual photosensitizers and photothermal agents for more efficient antitumor phototherapy via infrared low-power laser. Their ground and excited state properties, as well as the structural effect on their photophysical and biological properties, are investigated by spectroscopic, electrochemical, and quantum chemical theoretical calculations. They target mitochondria in human melanoma tumor cells and trigger apoptosis related to mitochondrial dysfunction upon irradiation. The Ir(III) complexes, particularly Ir6, demonstrate high phototherapy indexes to melanoma tumor cells and a manifest photothermal effect. Ir6, with minimal hepato-/nephrotoxicity in vitro, significantly inhibits the growth of melanoma tumors in vivo under 808 nm laser irradiation by dual photodynamic therapy and photothermal therapy and can be efficiently eliminated from the body. These results may contribute to the development of highly efficient phototherapeutic drugs for large, deeply buried solid tumors.

Methyl-ß-cyclodextrin induces programmed cell death in chronic myeloid leukemia cells and, combined with imatinib, produces a synergistic downregulation of ERK/SPK1 signaling.

Lipid rafts mediate several survival signals in the development of chronic myeloid leukemia (CML). Methyl-ß-cyclodextrin (MßCD) is an inhibitor specifically designed to disrupt lipid rafts in cells by depleting the cholesterol component. We hypothesize that treatment of CML cells with MßCD and imatinib could reduce imatinib resistance. Apoptotic and autophagic cell death was assayed using annexin V-propidium iodide double staining, immunoblotting, and immunocytochemistry. We next investigated whether MßCD could enhance the cytotoxicity of imatinib in imatinib-sensitive and imatinib-resistant K562 cells. Extracellular signal-regulated kinase/sphingosine kinase 1 signaling downstream of lipid raft-activated signaling pathways was significantly inhibited by treatment of cells with a combination of MßCD and imatinib compared with treatment with either agent alone. MßCD induces programmed cell death in CML cells, and its antileukemia action is synergistic with that of imatinib.

Efficacy and safety of raltitrexed plus S-1 versus regorafenib in patients with refractory metastatic colorectal cancer: a real-world propensity score matching study.

Background: Raltitrexed plus S-1 (RS) and regorafenib both showed considerable efficacy for metastatic colorectal cancer (mCRC) patients. This study aims to compare the effectiveness and safety of two different regimens in patients with refractory mCRC. Methods: This retrospective cohort study included mCRC patients who were treated with RS or regorafenib from February 2017 to June 2021. A propensity score matching (PSM) analysis was conducted to balance the baseline characteristics of all patients. Progression-free survival (PFS), overall survival (OS), tumor response, and safety of two regimens were evaluated. Results: A total of 187 patients were included in our study, with 107 patients in the RS group and 80 patients in the regorafenib group. After PSM, 78 pairs were recognized. Patients treated with RS had a semblable PFS compared to those treated with regorafenib before PSM (4.8 months vs 5.5 months, p = 0.400) and after PSM (4.7 months vs 5.4 months, p = 0.430). Patients in the RS group were associated with a longer OS than those in the regorafenib group (13.4 months vs 10.1 months, p = 0.010). A similar trend of OS was also obtained in the matched cohort (13.3 months vs 10.0 months, p = 0.024). Both objective response rate (12.8% vs 5.1%, p = 0.093) and disease control rate (53.8% vs 46.2%, p = 0.337) in the RS cohort were higher than those in the regorafenib group, without significant differences. Adverse events (AEs) of each group were well tolerated. Conclusion: Patients treated with RS demonstrated a longer OS than those treated with regorafenib and had manageable AEs, which could be recognized as a primary choice for refractory mCRC. Plain Language Summary: Efficacy and Safety of Raltitrexed plus S-1 Versus Regorafenib in Patients with Refractory Metastatic Colorectal Cancer: A Real-world Propensity Score Matching StudyBoth raltitrexed plus S-1 (RS) and regorafenib showed considerable efficacy for metastatic colorectal cancer (mCRC) patients. No study has compared the two regimens yet. Therefore, we compare the efficacy and safety between RS and regorafenib to provide an optimal treatment option. We retrospectively included patients with mCRC who failed at least two standard treatments. All enrolled patients received RS or regorafenib treatments. We conducted a propensity score matching to eliminate differences in the enrolled patients. After the analysis, we found no significant differences in progression-free survival in patients between the two groups. However, patients treated with RS had a longer OS than those treated with regorafenib, whether before matching (13.4 months vs 10.1 months, p = 0.010) or after matching (13.3 months vs 10.0 months, p = 0.024). In addition, the adverse effects caused by cancer-related therapy were tolerable for the patient. Certainly, this is a non-randomized retrospective study with a small sample size, so we conducted a propensity score matching to minimize potential bias. Importantly, this is the first research comparing the two treatments, and we believe that the results of this article could present a primary choice for clinical doctors dealing with patients with standard treatments that failed mCRC.

Dinuclear osmium complexes as mitochondrion-targeting antitumor photothermal agents in vivo.

Four dinuclear osmium complexes have been constructed for antitumor phototherapy. The most potent Os4 has extremely high photothermal conversion capability under irradiation of an 808 nm low-power laser, targets mitochondria in human melanoma cells without nucleus affinity, and acts as an antitumor photothermal therapy agent in vitro and in vivo.

Clinicopathologic features, treatment, survival, and prognostic factors of combined hepatocellular and cholangiocarcinoma: A nomogram development based on SEER database and validation in multicenter study.

PURPOSE: The aim of the study was to comprehensively understand the combined hepatocellular and cholangiocarcinoma (CHC) and develop a nomogram for prognostic prediction of CHC. METHODS: Data were collected from the Surveillance, Epidemiology and End Results (SEER) database (year 2004-2014). Propensity-score matching (PSM) was used to match the demographic characteristic of the CHC versus hepatocellular carcinoma (HCC) and intrahepatic cholangiocarcinoma (ICC). A nomogram model was established to predict the prognosis in terms of cancer specific survival (CSS). The established nomogram was externally validated by a multicenter cohort. RESULTS: A total of 71,756 patients enrolled in our study including 62,877 HCC patients, 566 CHC patients, and 8303 ICC patients. The CHC, HCC, and ICC are not exactly similar in clinical characteristic. After PSM, the CSS of CHC was better than HCC but comparable to ICC. Tumor size, M stage, surgery, chemotherapy, and surgery were independently prognostic factors of CHC and were included in the establishment of novel nomogram. The c-index of the novel nomogram in SEER training set and multicenter validation was 0.779 and 0.780, respectively, which indicated that the model was with better discrimination power. In addition, decision curve analyses proved the favorable potential clinical effect of the predictive model. Lastly, a risk classification based on nomogram also verified the reliability of the model. CONCLUSION: CHC had better survival than HCC but was comparable to ICC. The nomogram was established based on tumor size, M stage, chemotherapy, surgery, and radiotherapy and well validated by external multicenter cohort.

Bortezomib and sphingosine kinase inhibitor interact synergistically to induces apoptosis in BCR/ABl+ cells sensitive and resistant to STI571 through down-regulation Mcl-1.

Interactions between the proteasome inhibitor, bortezomib, and the sphingosine kinase (SPK1) inhibitor, SKI, were examined in BCR/ABL human leukemia cells. Coexposure of K562 or chronic myeloid leukemia (CML) cells from patients to subtoxic concentrations of SKI (10 µM) and bortezomib (100 nM) resulted in a synergistic increase in caspase-3 cleavage and apoptosis. These events were associated with the downregulation of BCR-ABL and Mcl-1, and a marked reduction in SPK1 expression. In imatinib mesylate-resistant K562 cells that displayed decreased BCR-ABL expression, bortezomib/SKI treatment markedly increased apoptosis and inhibited colony-formation in association with the downregulation of Mcl-1. Finally, the bortezomib/SKI regimen also potently induced the downregulation of BCR/ABL and Mcl-1 in human leukemia cells. Collectively, these findings suggest that combining SKI and bortezomib may represent a novel strategy in leukemia, including apoptosis-resistant BCR-ABL(+) hematologic malignancies.

Regulation of human hepatocellular carcinoma cells by Spred2 and correlative studies on its mechanism.

Members of the Spred gene family are negative regulators of the Ras/Raf-1/ERK pathway, which has been associated with several features of the tumor malignancy. However, the effect of Spred genes on hepatocellular carcinoma (HCC) remains uninvestigated. In the present work, we analyzed the in vitro and in vivo effects of Spred2 expression on the hepatic carcinoma cell line, SMMC-7721. In addition to attenuated ERK activation, which inhibited the proliferation and migration of unstimulated and HGF-stimulated SMMC-7721 cells. Adenovirus-mediated Spred2 overexpression induced the activation of caspase-3 and apoptosis, as well as reduced the expression level of Mcl-1. Most importantly, the knockdown of Spred2 markedly enhanced tumor growth in vivo. In conclusion, these results suggest that Spred2 could qualify as a potential therapeutic target in HCC.

Overexpression of microRNA-29b induces apoptosis of multiple myeloma cells through down regulating Mcl-1.

MicroRNAs (miRNAs) are small, noncoding ribonucleic acids (ncRNAs), which regulate gene expression by targeting mRNAs for translational repression and degradation. Several lines of evidences have indicated that miRNAs act as tumor suppressors and oncogenes. However, the role of miRNAs in pathogenesis of multiple myeloma (MM) remains unclear. In this study, we examined the profile of miRNA expression of primary MM cells, using miRNA microarray and quantitative real-time polymerase chain reaction (qPCR) techniques. These results showed that in the bone marrow specimens analyzed, miRNA-29b was significantly downregulated. Similar results were also observed in human myeloma cell lines (HMCLs). Adenovirus-mediated overexpression of miR-29b induced apoptosis and elevated caspase-3 activation in HMCLs. Using a bioinformatics approach, we found a perfect complementarity between miRNA-29b and the 3'UTR of myeloid-cell-leukemia 1(Mcl-1). It is further confirmed that miRNA-29b downregulated the level of Mcl-1 without effect on the mRNA level using both qRT-PCR assays and Western blot analyses. Moreover, we observed that enforced miR-29b expression by using a retarget miRNA-29b expression vector (Ad5F11p-miR-29b) could induce apoptosis and elevate caspase-3 activation in HMCLs. Our results also indicated that miRNA-29b-induced apoptosis acted antagonistically with IL-6 in HMCLs. These findings suggest that miRNA-29b may play an important role in MM as a tumor suppressor.

Overexpression of KAI1 induces autophagy and increases MiaPaCa-2 cell survival through the phosphorylation of extracellular signal-regulated kinases.

KAI1, a metastasis-suppressor gene belonging to the tetraspanin family, is known to inhibit cancer metastasis without affecting the primary tumorigenicity by inhibiting the epidermal growth factor (EGF) signaling pathway. Recent studies have shown that hypoxic conditions of solid tumors induce high-level autophagy and KAI1 expression. However, the relationship between autophagy and KAI1 remains unclear. By using transmission electron microscopy, confocal microscopy, and Western blotting, we found that KAI1 can induce autophagy in a dose- and time-dependent manner in the human pancreatic cell line MiaPaCa-2. KAI1-induced autophagy was confirmed by the expression of autophagy-related proteins LC3 and Beclin 1. KAI1 induces autophagy through phosphorylation of extracellular signal-related kinases rather than that of AKT. KAI1-induced autophagy protects MiaPaCa-2 cells from apoptosis and proliferation inhibition partially through the downregulation of poly [adenosine diphosphate (ADP)-ribose] polymerase (PARP) cleavage and caspase-3 activation.

Spred2 is involved in imatinib-induced cytotoxicity in chronic myeloid leukemia cells.

Spreds, a recently established class of negative regulators of the Ras-ERK (extracellular signal-regulated kinase) pathway, are involved in hematogenesises, allergic disorders and tumourigenesis. However, their role in hematologic neoplasms is largely unknown. Possible effects of Spreds on other signal pathways closely related to Ras-ERK have been poorly investigated. In this study, we investigated the in vitro effects of Spred2 on chronic myeloid leukemia (CML) cells. In addition to inhibiting the well-established Ras-ERK cascade, adenovirus-mediated Spred2 over-expression inhibits constitutive and stem cell factor (SCF)-stimulated sphingosine kinase-1 (SPHK1) and Mcl-1 expression, as well as inhibiting proliferation and inducing apoptosis in CML cells. In K562 cells and primary CML cells, imatinib induces endogenous Spred2 expression. Spred2 silencing by stable RNA interference partly protects K562 cells against imatinib-induced apoptosis. Together, these data implicate Spred2 in imatinib-induced cytotoxicity in CML cells, possibly by inhibiting the Ras-ERK cascade and the pro-survival signaling molecules SPHK1 and Mcl-1. These findings reveal potential targets for selective therapy of CML.

Genetic polymorphism of GSTP1: prediction of clinical outcome to oxaliplatin/5-FU-based chemotherapy in advanced gastric cancer.

The aim of this study was to evaluate the predictive value of the polymorphism Glutathione S-transferase P1 (GSTP1) Ile(105)Val on oxaliplatin/5-FU-based chemotherapy in advanced gastric cancer. Patients with advanced gastric cancer accepted oxaliplatin/5-FU-based chemotherapy as first-line chemotherapy were investigated. GSTP1 Ile(105)Val polymorphism was detected by TaqMan-MGB probe allelic discrimination method. Response to treatment was assessed by disease controlled rate. Time to progression, overall survival and toxicities were recorded. Final patient outcomes were as follows: the allele frequencies of GSTP1 were (105)Ile/(105)Ile 52%, (105)Ile/(105)Val 41% and (105)Val/(105)Val 7%. For patients with (105)Ile/(105)Ile and those with at least one (105)Val allele, disease control rate was 39% and 71% (P=0.026), respectively; median time to progression was 4.0 and 7.0 months (P=0.002); median overall survival time was 7.0 and 9.5 months (P=0.002). Neurological toxicity was more frequently occurred in patients with two (105)Ile alleles (P=0.005). In conclusion, patients with at least one (105)Val allele have better prognosis and response to oxaliplatin/5-FU-based regimen as first-line treatment for patients with advanced gastric cancer.

[Association between genetic polymorphisms of ERCC1, XRCC1, GSTP1 and survival of advanced gastric cancer patients treated with oxaliplatin/5-Fu-based chemotherapy].

OBJECTIVE: To evaluate the association between the polymorphisms of excision repair cross complementation group 1 (ERCC1), X-ray repair cross complementing 1 (XRCC1), glutathione S-transferase Pi 1 (GSTP1) and the survival of advanced gastric cancer patients treated with oxaliplatin-based combination chemotherapy. METHODS: Eighty five patients with advanced gastric cancer accepted oxaliplatin/5-FU-based chemotherapy as first-line chemotherapy were investigated. Peripheral venous blood was taken before chemotherapy. DNA was extracted from peripheral venous blood. The genetic polymorphisms were detected by real-time PCR assay. The association between time to progression, overall survival and the polymorphisms was analyzed. RESULTS: The median time to progression of the 85 cases was 5.3 months, and the median overall survival was 8.0 months. ERCC1-118 C/C, XRCC1-399 G/G and GSTP1-105 A/G + G/G were favorable genotypes and the number of the favorable genotypes was associated with survival of the patients. The median overall survival was 12.5 months, 10.0 months, 6.5 months and 4.5 months for patients with 3 favorable genotypes, 2 favorable genotypes, 1 favorable genotype and none favorable genotype, respectively, with a significant difference (χ(2) = 35.54, P < 0.01). CONCLUSION: Genetic polymorphisms of ERCC1-118, XRCC1-399 and GSTP1-105 are associated with TTP and OS of advanced gastric cancer patients treated with oxaliplatin/5-Fu-based combination chemotherapy as the first-line chemotherapy.

Arginine deprivation inhibits pancreatic cancer cell migration, invasion and EMT via the down regulation of Snail, Slug, Twist, and MMP1/9.

Arginine deprivation is currently being evaluated for its efficacy and safety in clinical trials aimed at combating tumors. However, the cellular signaling and molecular changes in response to such deprivation have not been systematically deciphered. Here, we evaluate the effect of arginine deprivation on human pancreatic cancer cells, with respect to their migratory and invasive potentials and their ability to undergo epithelial-mesenchymal transition (EMT). The transcription factors Snail, Slug, and Twist are regulators of EMT, as indicated by the suppression of E-cadherin and other epithelial markers and adhesion molecules. Our data indicated that arginine starvation inhibited the migration and impaired the adhesion and invasion of the pancreatic cancer cells, decreased Snail, Slug, and Twist expression, and increased E-cadherin expression without altering the expression of vimentin. It is well known that matrix metalloproteinases (MMPs) are important for the events that underlie tumor dissemination. Arginine starvation inhibited the expression of MMP-1 and MMP-9. Furthermore, the PI3K/Akt pathway was altered when the pancreatic cancer cells underwent arginine deprivation as exhibited by the decreased Akt phosphorylation. Thus, these data reveal that arginine deprivation has the potential to decrease the metastatic ability of pancreatic cancer cells.

Endocrine glands-derived vascular endothelial growth factor protects pancreatic cancer cells from apoptosis via upregulation of the myeloid cell leukemia-1 protein.

Endocrine glands-derived vascular endothelial growth factor (EG-VEGF, also termed as Prok1)--a novel cytokine that selectively acts on the endothelial cells of endocrine glands--was recently reported to be involved in the regulation of tumor cell growth and survival. However, its roles in the regulation of pancreatic cancer progression remain unclear. In this report, we investigated the suppressive effects of EG-VEGF on pancreatic cancer cell apoptosis and the relevant mechanisms. By using reverse-transcriptase polymerase chain reaction (RT-PCR) we found that the Mia PaCa II cells of the pancreatic cancer cell line express the mRNAs of both EG-VEGF (Prok1) and its receptors. EG-VEGF protects pancreatic cancer cells from apoptosis through upregulation of myeloid cell leukemia-1 (Mcl-1), an anti-apoptotic protein of the bcl-2 family. Treatment of pancreatic cancer cells with EG-VEGF results in the rapid phosphorylation of mitogen-activated protein kinase (MAPK), STAT3, and AKT, which are involved in the upregulation of Mcl-1 expression. EG-VEGF (Prok1) protects Mia PaCa II cells from apoptosis through G protein-coupled receptor (GPR)-induced activation of multiple signal pathways, and hence can be a novel target for pancreatic cancer therapy.

Hepatocyte growth factor protects endothelial cells against gamma ray irradiation-induced damage.

AIM: To investigate the effect of HGF on proliferation, apoptosis and migratory ability of human vascular endothelial cells against gamma ray irradiation. METHODS: ECV304 cells derived from adult human umbilical vein endothelial cells (HUVEC) were irradiated with a single gamma ray dose of 20 Gy. Immunocytochemistry and Western blot analysis were used to detect c-Met protein expression and HGF/c-Met signal pathway. In the HGF-treated groups, ECV304 cells were incubated with HGF (20 or 40 ng/mL) 3 h prior to irradiation. At 48 h post-irradiation, the proliferation of ECV304 cells was measured by MTT assay, the apoptosis was assessed by flow cytometry, and the migratory ability of ECV304 cells was measured by transwell chamber assay. RESULTS: c-Met protein is expressed in ECV304 cells and can be activated by HGF. Gamma ray irradiation inhibits proliferation and migration of ECV304 cells in a dose-dependent manner. HGF significantly promoted the proliferation of ECV304 cells, and flow cytometry revealed that HGF can inhibit apoptosis of ECV304 cells. Transwell chamber assay also showed that HGF increases migration activity of endothelial cells. CONCLUSION: HGF may afford protection to vascular endothelial cells against gamma ray irradiation-induced damage.