Research Progress of Baihe Gujin Decoction in the Treatment of Lung Cancer.

Baihe Gujin decoction is one of the most commonly used decoction in traditional Chinese medicine for the treatment of lung cancer. It can nourish yin and moisten the lung as well as prevent phlegm from forming and stop coughing. On the one hand, Baihe Gujin decoction is characterized with extensive application, proven efficacy, a long history, and high safety. On the other hand, Baihe Gujin decoction can induce apoptosis of tumor cells, improve immune function and inhibit inflammation. The main anti-tumor components of this include kaempferol, quercetin, isorhamnetin, glycyrrhizin and ß-sitosterol. Clinically, Baihe Gujin decoction can improve the adverse reactions caused by radiotherapy, chemotherapy and immunotherapy for lung cancer, enhance the quality of life of patients, and prolong their survival time. At present, there are a large number of clinical and basic researches on the treatment of lung cancer with Baihe Gujin decoction. In this paper, we mainly discussed the treatment of lung cancer with Baihe Gujin decoction through analyzing basic and clinical researches at home and abroad in the past 20 years. Through the discussion, we aimed to probe deeper into Baihe Gujin decoction for the treatment of lung cancer, thereby providing a broader idea for clinical diagnosis and treatment of lung cancer.

Hsa-miR-877-5p Expression in Acute Ischemic Stroke Based on Bioinformatics Analysis and Clinical Validation.

Inflammation and immunity play important roles in the pathogenesis of ischemic stroke. This study aimed to explore key regulatory genes in acute ischemic stroke (AIS) and their underlying mechanisms to provide new research targets for the diagnosis and treatment of ischemic stroke. We searched for differentially expressed mRNAs and miRNAs in patients with AIS and healthy populations in GEO databases, constructed a miRNA-mRNA network, and screened key miRNAs using least absolute shrinkage and selection operator regression and the support vector machine-recursive feature elimination model. Correlations between key miRNAs and infiltrating immune cells and inflammatory factors were analyzed using CIBERSORT and immunoassays and verified using clinical experiments. Bioinformatics analysis identified hsa-miR-877-5p as a key regulatory miRNA in AIS that can modulate immune and inflammatory responses. In clinical studies, it was verified by quantitative PCR analysis that the expression of hsa-miR-877-5p in the blood of AIS patients was higher than that of the healthy group. Then, enzyme-linked immunosorbent assay revealed that the expression of IL-23 and TNF-α related to inflammation in AIS patients was higher than that of the healthy. Quantitative PCR further found that the relative mRNA expression of IL-23, CXCR3, and TNF-α in AIS group was higher than that of the healthy group. This study may provide a basis for a more comprehensive understanding of the potential mechanism of the occurrence and development of AIS, and hsa-miR-877-5p and its downstream effectors IL-23, CXCR3, and TNF-α may be potential intervention targets in AIS.

Knockdown of LINC01087 inhibits gastric cancer malignant behavior by regulating the miR-135a-5p/CAAP1 axis.

Long noncoding RNAs play important roles in the occurrence and development of many malignant cancers. This study focuses on the effects of LINC01087 on gastric cancer and its underlying mechanism. In the present study, LINC01087 and CAAP1 were found to be upregulated, and miR-135a-5p was diminished in gastric cancer specimens and cells. Inhibition of LINC01087 resulted in cell proliferation inhibition and induced cell apoptosis through the intrinsic apoptosis signaling pathway, as evidenced by the activation of caspase-3 and caspase-9. An investigation of the signaling pathway revealed that the effects on proliferation and apoptosis following LINC01087 knockdown were mediated by suppression of CAAP1. Furthermore, application of a miR-135a-5p inhibitor or overexpression of CAAP1 could attenuate the apoptotic effect achieved by LINC01087 inhibition, confirming the involvement of miR-135a-5p/CAAP1 signaling in the occurrence of gastric cancer. In conclusion, the LINC01087/miR-135a-5p/CAAP1 axis modulates gastric cancer tumorigenesis and pathogenesis and presents new insight into gastric cancer targeted therapy.

Aged microplastics enhance their interaction with ciprofloxacin and joint toxicity on Escherichia coli.

Microplastics (MPs) in natural environments undergo complex aging processes, changing their interactions with coexisting antibiotics, and posing unpredictable ecological risks. However, the joint toxicity of aged MPs (aMPs) and antibiotics to bacteria, especially at the molecular level, is unclear. In this study, non-thermal plasma technology was used to simultaneously simulate various radical oxidation and physical reactions that occur naturally in the environment, breaking the limitation of simple aging process in laboratory aging technologies. After aging, we investigated the altered properties of aMPs, their interactions with ciprofloxacin (CIP), and the molecular responses of E. coli exposed to pristine MPs (13.5 mg/L), aMPs (13.5 mg/L), and CIP (2 µg/L) individually or simultaneously. aMPs bound far more CIP to their surfaces than pristine MPs, especially in freshwater ecosystems. Notably, the growth of E. coli exposed to aMPs alone was inhibited, whereas pristine MPs exposure didn't affect the growth of E. coli. Moreover, the most differentially expressed genes in E. coli were induced by the coexposure of aMPs and CIP. Although E. coli depended on chemotaxis to improve its flagellar rotation and escaped the stress of pollutants, the coexposure of aMPs and CIP still caused cell membrane damage, oxidative stress, obstruction of DNA replication, and osmotic imbalance in E. coli. This study filled the knowledge gap between the toxicity of aMPs and pristine MPs coexisting with antibiotics at the transcription level, helping in the accurate assessment of the potential risks of MPs to the environment.

AOPs enhance the migration of polystyrene nanoparticles in saturated quartz sand.

Wastewater treatment plants are suspected to be significant point sources of microplastic and nanoplastic particles (NPs) in the environment. As one of the main wastewater treatment processes, advanced oxidation processes (AOPs) may change the physicochemical properties of NPs and further affect their migration. However, limited information is known about the environmental fate of NPs after AOP treatment. In this study, polystyrene nanoparticles were treated using two representative AOPs, Fenton and persulfate treatments, and the migration of the NPs in quartz sand was investigated via column transport experiments. FTIR and XPS analysis indicated that a large number of oxygen-containing groups were generated on the NP surface after AOP treatment leading to lower hydrophobicity and a higher negative charge. Besides, the C/O ratio after Fenton and persulfate treatments was increased from 10.98 to 7.25 and 8.68. Moreover, the NPs after AOP treatment exhibited higher mobility in quartz sand in both ultrapure water and 10 mM NaCl solution. It was more obvious in 10 mM NaCl solution with breakthrough percentages of 79.73% for P-PS, 90.97% for F-PS and 95.67% for N-PS, respectively. These results could be explained by the roles of generated oxygen-containing functional groups; first, the higher negative charge enhanced the electrostatic repulsion between treated NPs and sand; second, lower hydrophobicity improved the binding with water molecules in background solution. This work is helpful in understanding the changes of nanoplastics in AOP treatment and their migration in the natural environment, which has far-reaching influence on the environmental fate and behavior of nanoplastics.

Fast Fabrication of Fishnet Optical Metamaterial Based on Femtosecond Laser Induced Stress Break Technique.

To speed up the fabrication of optical metamaterials by making use of the fast speed advantage of femtosecond laser preparation, a metamaterial appropriate for femtosecond laser processing was designed, and the interaction between femtosecond laser and metal-dielectric-metal fishnet stacks was investigated in detail. Two kinds of processing mechanisms, thermal melting and stress break, were revealed during the fabrication. The thermal melting process, dominated by the interaction of femtosecond laser with metals, makes the upper and lower metal layers adhere to each other, which leads to the magnetic resonance impossible. The stress break process, dominated by the interaction of femtosecond laser with dielectrics, can keep the upper and lower metal coatings isolated. Fishnet optical metamaterial was fabricated by femtosecond laser-induced stress break technique, using back side ablation, high numerical aperture and super-Gaussian beam. The resolution and speed can reach 500 nm, and 100 units/s, respectively. Spectrophotometer measurement results proved that the magnetic resonances were found in the fishnet nanostructure. The theoretical refractive index of the metamaterial on a glass substrate reached -0.12 at the wavelength of 3225 nm. It proved that femtosecond laser-induced stress break was a good and fast tool during the fabrication of optical metamaterials.

Evaluation of sublethal and transgenerational effects of sulfoxaflor on Aphis gossypii via life table parameters and 16S rRNA sequencing.

BACKGROUND: Aphis gossypii, a polyphagous and recurrent pest induced by pesticides, causes tremendous loss crop yields each year. Previous studies on the mechanism of pesticide-induced sublethal effects mainly focus on the gene level. The symbiotic bacteria are also important participants of this mechanism, but their roles in hormesis are still unclear. RESULTS: In this study, life table parameters and 16S rRNA sequencing were applied to evaluate the sublethal and transgenerational effects of sulfoxaflor on adult A. gossypii after 24-h LC20 (6.96 mg L-1 ) concentration exposure. The results indicated that the LC20 of sulfoxaflor significantly reduced the finite rate of increase (λ) and net reproductive rate (R0 ) of parent generation (G0), and significantly increased mean generation time (T) of G1 and G2, but not of G3 and G4. Both reproductive period and fecundity of G1 and G2 were significantly higher than those of the control. Furthermore, our sequencing data revealed that more than 95% bacterial communities were dominated by the phylum Proteobacteria, in which the maximum proportion genus was the primary symbiont Buchnera and the facultative symbiont Arsenophonus. Compared to those of the control, the abundance and composition of symbiotic bacteria of A. gossypii for three successive generations (G0-G2) were changed after G0 A. gossypii was exposed to sulfoxaflor: the diversity of the bacterial community was decreased, but the abundance of Buchnera was increased (G0), while the abundance of Arsenophonus was decreased. Contrary to G0, G1 and G2 cotton aphid exhibited an increased relative abundance of Arsenophonus in the sublethal treatment group. CONCLUSION: Taken together, our results provide an insight into the interactions among pesticide resistance, aphids, and symbionts, which will eventually help to better manage the resurgence of A. gossypii. © 2021 Society of Chemical Industry.

Effects of natural organic matter on the photolysis of tetracycline in aquatic environment: Kinetics and mechanism.

The residues of tetracycline in environment have raised increasing concern for the deleterious impact on ecological and human health. Natural organic matter (NOM), ubiquitous in natural waters, is unavoidable to encounter tetracycline, which might affect the fate of tetracycline in aquatic environment. In this study, we investigated the effect of natural organic matter (NOM) on the photolytic fate of tetracycline (TC). The photolysis kinetics of TC were evaluated with two representative NOM, tannic acid (TA) and gallic acid (GA). The presence of TA and GA obviously inhibited the removal of TC under UV irradiation with photolysis rate constant at 0.067 h-1 and 0.071 h-1, respectively, which were 32.3% and 28.3% less than that without TA and GA (0.099 h-1). Furthermore, NOM exhibited different impacts on both indirect photolysis and direct photolysis. NOM promoted the formation of hydroxyl radical, induced the generation of triplet-excited state NOM and thus greatly enhanced the indirect photolysis of TC. However, direct photolysis was almost completely inhibited by NOM via inner filter effect and interacting with TC to form ground-state complex with low photoreactive. Moreover, similar intermediates were detected in the presence and absence of NOM, indicating that NOM exhibited limited influence on the degradation pathways of TC. This study reveals the multiple roles of NOM on tetracycline photolysis, contributing to better understand the photolytic fate of antibiotics in natural waters.

Effects of neural stem cell transplantation on the motor function of rats with contusion spinal cord injuries: a meta-analysis.

OBJECTIVE: To judge the efficacies of neural stem cell (NSC) transplantation on functional recovery following contusion spinal cord injuries (SCIs). DATA SOURCES: Studies in which NSCs were transplanted into a clinically relevant, standardized rat model of contusion SCI were identified by searching the PubMed, Embase and Cochrane databases, and the extracted data were analyzed by Stata 14.0. DATA SELECTION: Inclusion criteria were that NSCs were used in in vivo animal studies to treat contusion SCIs and that behavioral assessment of locomotor functional recovery was performed using the Basso, Beattie, and Bresnahan lo-comotor rating scale. Exclusion criteria included a follow-up of less than 4 weeks and the lack of control groups. OUTCOME MEASURES: The restoration of motor function was assessed by the Basso, Beattie, and Bresnahan locomotor rating scale. RESULTS: We identified 1756 non-duplicated papers by searching the aforementioned electronic databases, and 30 full-text articles met the inclusion criteria. A total of 37 studies reported in the 30 articles were included in the meta-analysis. The meta-analysis results showed that transplanted NSCs could improve the motor function recovery of rats following contusion SCIs, to a moderate extent (pooled standardized mean difference (SMD) = 0.73; 95% confidence interval (CI): 0.47-1.00; P < 0.001). NSCs obtained from different donor species (rat: SMD = 0.74; 95% CI: 0.36-1.13; human: SMD = 0.78; 95% CI: 0.31-1.25), at different donor ages (fetal: SMD = 0.67; 95% CI: 0.43-0.92; adult: SMD = 0.86; 95% CI: 0.50-1.22) and from different origins (brain-derived: SMD = 0.59; 95% CI: 0.27-0.91; spinal cord-derived: SMD = 0.51; 95% CI: 0.22-0.79) had similar efficacies on improved functional recovery; however, adult induced pluripotent stem cell-derived NSCs showed no significant efficacies. Furthermore, the use of higher doses of transplanted NSCs or the administration of immunosuppressive agents did not promote better locomotor function recovery (SMD = 0.45; 95% CI: 0.21-0.70). However, shorter periods between the contusion induction and the NSC transplantation showed slightly higher efficacies (acute: SMD = 1.22; 95% CI: 0.81-1.63; subacute: SMD = 0.75; 95% CI: 0.42-1.09). For chronic injuries, NSC implantation did not significantly improve functional recovery (SMD = 0.25; 95% CI: -0.16 to 0.65). CONCLUSION: NSC transplantation alone appears to be a positive yet limited method for the treatment of contusion SCIs.

Synthesis and bioactivity studies of sex pheromone analogs of the diamond back moth, Plutella xylostella.

BACKGROUND: Diamondback moth, Plutella xylostella L., is a very important pest of cruciferous vegetables causing excessive economic losses worldwide. Bioactivities of halo-, diazo-, and cyclopropane acetates of P. xylostella sex pheromone have been evaluated using electrophysiology and enzyme inhibition assays. RESULTS: A total of 23 sex pheromone analogs of P. xylostella were designed and synthesized and the result shows that (11Z)-hexadec-11-en-1-yl 2,2,2-trifluoroacetate, (11Z)-hexadec-11-en-1-yl 2,2,3,3,3-pentafluoropropanoate, and (11Z)-hexadec-11-en-1-yl trifluoromethanesulfonate elicited potential inhibitory effects at all doses tested in the electrophysiology and enzyme inhibition assays. Interference of locating the sex pheromone source was found strongest when these three analogs were mixed with the sex pheromone at a 10:1 ratio. In addition, field test showed that the rate of mating disruption was over 90% when (11Z)-hexadec-11-en-1-yl 2,2,2-trifluoroacetate or (11Z)-hexadec-11-en-1-yl 2,2,3,3,3-pentafluoropropanoate was mixed with the sex pheromone at a 10:1 ratio. CONCLUSION: Two sex pheromone antagonists were screen out by electrophysiology, enzyme inhibition assays, wind tunnel and field tests. We believe that these antagonists could be used to establish a novel eco-friendly measure to control P. xylostella and provide evidence for clarifying the specific functions and molecular mechanisms of sex pheromone antagonists. © 2018 Society of Chemical Industry.

A facile heterogeneous system for persulfate activation by CuFe2O4 under LED light irradiation.

In this study, the removal performance for rhodamine B (RB) by persulfate (PS) activated by the CuFe2O4 catalyst in a heterogeneous catalytic system under LED light irradiation was investigated. The effect of vital experimental factors, including initial solution pH, CuFe2O4 dosage, PS concentration, co-existing anion and initial RB concentration on the removal of RB was systematically studied. The removal of RB was in accordance with the pseudo first-order reaction kinetics. Over 96% of 20 mg L-1 RB was removed in 60 min using 0.5 g L-1 CuFe2O4 catalyst and 0.2 mM PS at neutral pH. In addition, free radical quenching experiments and electron spin resonance (EPR) experiments were performed, which demonstrated the dominant role of sulfate radical, photogenerated holes and superoxide radical in the CuFe2O4/PS/LED system. The morphology and physicochemical properties of the catalyst were characterized by XRD, SEM-EDS, TEM, N2 adsorption-desorption isotherm, UV-vis DRS, and XPS measurements. Moreover, 18.23% and 38.79% total organic carbon (TOC) removal efficiency was reached in 30 min and 60 min, respectively. The catalyst revealed good performance during the reusability experiments with limited iron and copper leaching. Eventually, the major intermediates in the reaction were detected by GC/MS, and the possible photocatalytic pathway for the degradation of RB in the CuFe2O4/PS/LED system was proposed. The results suggest that the CuFe2O4/PS/LED system has good application for further wastewater treatment.

Effect of NaCl-stressed Bacillus thuringiensis (Bt) cotton on the feeding behaviors and nutritional parameters of Helicoverpa armigera.

Saline-alkali soil is an arable land resource on which transgenic Bacillus thuringiensis (Bt) cotton has been planted on a large scale in accordance with food security strategies. There are, however, concerns about the insecticidal effects of Bt cotton on target insect pests. In this study, a Bt cotton variety, GK19, and its nontransgenic parent variety, Simian-3, were used as experimental models for investigating the effect of the expression of exogenous insecticidal proteins in Bt cotton under NaCl stress on the feeding behavior and nutritional parameters of Helicoverpa armigera. The results showed that the expression of exogenous insecticidal proteins in GK19 was significantly inhibited under NaCl stress. However, the feeding, crawling, resting and spinning down behavior of the 5th instar H. armigera larvae on GK19 Bt cotton, as well as the amount of food consumed and feces produced by these larvae, did not markedly differ under different NaCl concentrations. In contrast, the mean relative growth rate (MRGR), relative growth rate (RGR), approximate digestibility (AD), efficiency of conversion of ingested food (ECI) and efficiency of conversion of digested food (ECD) of the larvae markedly decreased in response to NaCl stress. Under the same concentration of NaCl, the nutritional parameters of the bollworm larvae on GK19 Bt cotton or Simian-3 nontransgenic cotton were different. However, the interaction between salt stress and cotton variety had no significant effect on the feeding behavior or nutritional parameters of H. armigera larvae. These results may provide a scientific basis for determining the effect of exogenous insecticidal protein expression in Bt cotton under NaCl stress on H. armigera and can therefore be useful for the effective application of Bt cotton in saline-alkali soils to prevent and control H. armigera.

Overoxidized polypyrrole/graphene nanocomposite with good electrochemical performance as novel electrode material for the detection of adenine and guanine.

Most conducting polymer/graphene composites have excellent electrical conductivity. However, the background currents of these composites modified electrodes are much larger. In order to improve the sensitivities of these methods, it is necessary to decrease the background signal. In this paper, porous structure films of overoxidized polypyrrole/graphene (PPyox/GR) have been electrochemically coated onto glassy carbon electrode (GCE) and successfully utilized as an efficient electrode material for the quantitive detection of adenine and guanine, two of the most important components of DNA and RNA. The permselective polymer coatings with low background current could improve the selectivity and sensitivity of microelectrodes for the electropositive purine bases. The GRs into these polymers would further improve sensitivity by increasing the electroactive surface area. The electrochemical sensor can be applied to the quantification of adenine and guanine with a linear range covering 0.06-100 µM and 0.04-100 µM, and a low detection limit of 0.02 µM and 0.01 µM, respectively. More importantly, the proposed method was applied to quantify adenine and guanine in calf thymus DNA with satisfactory results.

Electroactive species-doped poly(3,4-ethylenedioxythiophene) films: enhanced sensitivity for electrochemical simultaneous determination of vitamins B2, B6 and C.

Herein, functionalized PEDOT films were prepared by incorporation of two electroactive species, ferrocenecarboxylic acid (Fc(-)) and ferricyanide (Fe(CN)6(4-)) as doping anions during the electropolymerization of PEDOT at glassy carbon electrodes (GCEs) from aqueous solution. The electrochemically synthesized electroactive species-doped PEDOT films have been carefully characterized by scanning electron microscopy (SEM), FTIR and UV/Vis spectra and various electrochemical techniques. Such nanostructured films combined the advantages of PEDOT (high conductivity and stability) together with electroactive species (good electrochemical activity) and were applied as electrochemical sensors for simultaneous determination of vitamin B2 (VB2), vitamin B6 (VB6) and vitamin C (VC). The results showed that the oxidation peak currents of vitamins obtained at the GCEs modified with electroactive species-doped PEDOT films were much higher than those at the ClO4(-)-doped PEDOT films and bare GCEs. The experiment results also illustrated that the sensors possessed high selectivity with no interference from other potential competing species. Moreover, the proposed sensors were successfully employed for the determination of vitamins in orange juice samples with satisfactory results.

Targeting trastuzumab-resistant breast cancer cells with a lentivirus engineered to bind antibodies that recognize HER-2.

Targeting HER-2 over-expressing breast cancer cells with trastuzumab has resulted in significant improvements in both disease-free and overall survival rates. However, despite a favorable initial response, some cancer cells become resistant and develop into fatal metastatic disease. Here we report that we can specifically target HER-2 over-expressing and trastuzumab-resistant breast cancer cells by using an engineered lentivirus which has trastuzumab bound to its envelope. In vitro, this lentiviral construct mediated both the expression of reporter genes, such as enhanced green fluorescent protein (EGFP) and firefly luciferase, as well as the therapeutic gene, herpes thymidine kinase (hTK), in HER-2 over-expressing cells. Subsequent application of the pro-drug ganciclovir selectively killed breast cancer cells in which lentivirus mediated expression of hTK. In vivo, we successfully targeted the expression of firefly luciferase to trastuzumab-resistant breast cancer tumors established in nude mice. Furthermore, we found that systemic administration of trastuzumab-bound lentivirus led to expression of EGFP in circulating trastuzumab-resistant breast cancer cells. In conclusion, HER-2 over-expressing breast cancer cells resistant to trastuzumab can be targeted for selective gene expression and destruction by viruses with envelope-proteins engineered to bind to this antibody.

To die or to survive, a fatal question for the destiny of prostate cancer cells after androgen deprivation therapy.

Prostate cancer is the most frequently diagnosed non-skin cancer in adult males in North America and is the second leading cause of cancer-related mortality. For locally advanced or metastatic disease, androgen deprivation, through medical or surgical castration, is the primary treatment to induce prostate cancer cell death and extend patient survival. However, the vast majority of cancers progress to a castration-resistant/androgen-independent state where the cell death processes are no longer active. This review describes the main cell death processes, apoptosis, autophagy, necrosis and necroptosis, which may be activated in prostate cancers after androgen deprivation therapy as well as the molecular mechanisms through which the cancers progress to become castration resistant. In particular, the central role of persistent androgen receptor (AR)-mediated signaling and AR crosstalk with other critical cell signaling pathways, including (i) the PI3K/Akt pathway, (ii) receptor tyrosine kinases, (iii) the p38 MAPK pathway, and (iv) the Wnt/ß-catenin pathway, as well as reactivation of AR by de novo synthesized androgen are discussed in this context. Understanding the molecular changes that subvert normal cell death mechanisms and thereby compromise the survival of prostate cancer patients continues to be a major challenge.

Bioengineered viral vectors for targeting and killing prostate cancer cells.

Enabling the transduction of therapeutic gene expression exclusively in diseased sites is the key to developing more effective treatments for advanced prostate cancer using viral-based therapy. While prostate cancers that express high levels of HER-2 are resistant to the killing effects of trastuzumab, they can be targeted for selective gene expression and destruction by lentiviruses with envelope proteins engineered to bind to this therapeutic antibody. More importantly, after intravenous injection, this trastuzumab-bound lentivirus is able to target castration-resistant prostate tumor xenografts, albeit with low efficiency. This proof of principle opens up multiple possibilities for the prevention and treatment of prostate cancer using a viral-based therapy. However, to be safe and more effective, the viral vectors must target prostate cancer cells more selectively and efficiently. A higher degree of specificity and efficiency of cancer cell targeting can be achieved by engineering viral vectors to bind to a specific cell surface marker and by controlling the expression of the therapeutic payload at transcriptional level, with a tissue-specific promoter, and at the translational level, with a regulatory sequences inserted into either the 5'UTR or 3'UTR regions of the therapeutic gene(s). The latter would be designed to ensure that translation of this mRNA occurs exclusively in malignant cells. Furthermore, in order to obtain a potent anti-tumor effect, viral vectors would be engineered to express pro-apoptotic genes, intra-cellar antibodies/nucleotide aptamers to block critical proteins, or siRNAs to knockdown essential cellular mRNAs. Alternatively, controlled expression of an essential viral gene would restore replication competence to the virus and enable selective oncolysis of tumor cells. Successful delivery of such bioengineered viruses may provide a more effective way to treat advanced prostate cancer.

Down-regulation of type I interferon receptor sensitizes bladder cancer cells to vesicular stomatitis virus-induced cell death.

The intrinsic oncolytic specificity of vesicular stomatitis virus (VSV) is currently being exploited to develop alternative therapeutic strategies for bladder cancer and other cancers. Previously we reported that oncolytic VSV is a potent agent for intravesical treatment of high risk bladder cancer. We observed that VSV preferentially targeted bladder cancer cells resistant to type I interferon (IFN) treatment. The goal of the current study was to further elucidate the nature of the molecular defect of IFN signaling by which bladder cancer cells become susceptible to VSV infection. Using a tissue microarray composed of human bladder cancer cores, we observed that expression of type I IFN receptor (IFNAR) was decreased relative to normal bladder tissue. Advanced bladder cancers had even lower expression of IFNAR. We found that bladder cancer cells susceptible to VSV-induced lysis had low expression of IFNAR as well. We hypothesized that down-regulation of IFNAR in bladder cancer cells may be a molecular mechanism responsible for resistance to type I IFN treatment and sensitivity to VSV oncolysis. SiRNA knockdown of IFNAR indeed facilitated replication of VSV in cells previously resistant to VSV treatment. Blocking IFNAR with a neutralizing antibody showed a similar effect. Hence down-regulation of IFNAR in bladder cancer may be one of the primary molecular mechanisms for clinical IFN resistance. However, this also facilitates VSV replication and oncolysis in high risk bladder cancers and provides a basis for selecting bladder cancer patients for IFN or oncolytic VSV therapy in future clinical trials.

Multiple aspects of the phenotype of mammary epithelial cells transformed by expression of activated M-Ras depend on an autocrine mechanism mediated by hepatocyte growth factor/scatter factor.

Multiple aspects of the transformed phenotype induced in a murine mammary epithelial cell line scp-2 by expression of activated G22V M-Ras, including maintainance of cell number at low density, anchorage-independent growth, invasion of Matrigel, and secretion of matrix metalloproteinases (MMP) 2 and 9, were dependent on an autocrine mechanism. Conditioned medium from dense cultures of scp-2 cells expressing G22V M-Ras, but not from parental cells, induced activation of Erk and Akt in cells expressing G22V M-Ras, maintained the cell number and promoted anchorage-independent growth of cells expressing G22V M-Ras (although not the parental cells), and induced scattering of MDCK cells. The latter activities were blocked by neutralizing antibodies to hepatocyte growth factor/scatter factor (HGF/SF) and could be mimicked by HGF/SF. Anti-HGF/SF antibodies also inhibited invasion of Matrigel, and the production of MMP-2 and MMP-9, together with urokinase-type plasminogen activator, was secreted by G22V M-Ras scp-2 cells but not by parental cells. Invasion of Matrigel was blocked by an inhibitor of MMPs, BB94, and by the mitogen-activated protein kinase kinase 1/2 kinase inhibitor PD98059 but was only marginally affected by the phosphatidylinositol 3-kinase inhibitor LY294002. Autocrine HGF/SF was thus critical for expression of key features of the phenotype of mammary epithelial cells transformed by expression of activated M-Ras.

Expression of activated M-Ras in a murine mammary epithelial cell line induces epithelial-mesenchymal transition and tumorigenesis.

The expression of activated mutants of M-Ras (G22V or Q71L), but not wild-type M-Ras, in a murine mammary epithelial cell line, scp2, resulted in epithelial-mesenchymal transition (EMT) and oncogenic transformation. Cells expressing constitutively active M-Ras continued to grow in the absence of serum and exhibited a loss of the epithelial markers cytokeratin, E-cadherin and beta-catenin, together with a gain of the mesenchymal marker vimentin, a loss of contact inhibition in monolayer growth and a gain of the capacity for anchorage-independent growth. Moreover, unlike the parental cells, they failed to form differentiated mammospheres on Matrigel and instead formed branched networks of cells that grew and invaded the Matrigel. The expression of activated p21 Ras (G12V H-Ras or Q61K N-Ras) also resulted in EMT and tumorigenesis, although there was evidence that expression of higher levels was toxic. Tumors derived from scp2 cells expressing activated M-Ras exhibited activation of Akt and of ERK. The levels of expression of Q71L M-Ras and G12V H-Ras required for tumorigenesis were comparable, although higher levels of the weaker G22V M-Ras mutant were selected for in vivo. These data indicate that the expression of activated mutants of M-Ras was sufficient for oncogenic transformation of a murine mammary epithelial cell line.