PKC-ζ mediated reduction of the extracellular vesicles-associated TGF-ß1 overcomes radiotherapy resistance in breast cancer.

BACKGROUND: Radiotherapy is widely applied in breast cancer treatment, while radiotherapy resistance is inevitable. TGF-ß1 has been considered to be an endogenous factor for the development of radiotherapy resistance. As a large portion of TGF-ß1 is secreted in an extracellular vesicles-associated form (TGF-ß1EV), particularly in radiated tumors. Thus, the understanding of the regulation mechanisms and the immunosuppressive functions of TGF-ß1EV will pave a way for overcoming the radiotherapy resistance in cancer treatment. METHODS: The superoxide-Zinc-PKC-ζ-TGF-ß1EV pathway in breast cancer cells was identified through sequence alignments of different PKC isoforms, speculation and experimental confirmation. A series of functional and molecular studies were performed by quantitative real-time PCR, western blot and flow cytometry analysis. Mice survival and tumor growth were recorded. Student's t test or two-way ANOVA with correction was used for comparisons of groups. RESULTS: The radiotherapy resulted in an increased expression of the intratumoral TGF-ß1 and an enhanced infiltration of the Tregs in the breast cancer tissues. The intratumoral TGF-ß1 was found mainly in the extracellular vesicles associated form both in the murine breast cancer model and in the human lung cancer tissues. Furthermore, radiation induced more TGF-ß1EV secretion and higher percentage of Tregs by promoting the expression and phosphorylation of protein kinase C zeta (PKC-ζ). Importantly, we found that naringenin rather than 1D11 significantly improved radiotherapy efficacy with less side effects. Distinct from TGF-ß1 neutralizing antibody 1D11, the mechanism of naringenin was to downregulate the radiation-activated superoxide-Zinc-PKC-ζ-TGF-ß1EV pathway. CONCLUSIONS: The superoxide-zinc-PKC-ζ-TGF-ß1EV release pathway was elucidated to induce the accumulation of Tregs, resulting in radiotherapy resistance in the TME. Therefore, targeting PKC-ζ to counteract TGF-ß1EV function could represent a novel strategy to overcome radiotherapy resistance in the treatment of breast cancer or other cancers. TRIAL REGISTRATION: The using of patient tissues with malignant Non-Small Cell Lung Cancer (NSCLC) was approved by the ethics committees at Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China (NCC2022C-702, from June 8th, 2022).

[Effects of Rehmanniae Radix and Rehmanniae Radix Praeparata on proteomics and autophagy in mice with type 2 diabetes mellitus induced by high-fat diet coupled with streptozotocin].

To compare the pancreatic proteomics and autophagy between Rehmanniae Radix-and Rehmanniae Radix Praeparata-treated mice with type 2 diabetes mellitus(T2DM). The T2DM mouse model was established by high-fat diet coupled with streptozotocin(STZ, intraperitoneal injection, 100 mg·kg~(-1), once a day for three consecutive days). The mice were then randomly assigned into a control group, low-(5 g·kg~(-1)) and high-dose(15 g·kg~(-1)) Rehmanniae Radix groups, low-(150 mg·kg~(-1)) and high-dose(300 mg·kg~(-1)) catalpol groups, low-(5 g·kg~(-1)) and high-dose(15 g·kg~(-1)) Rehmanniae Radix Praeparata groups, low-(150 mg·kg~(-1)) and high-dose(300 mg·kg~(-1)) 5-hydroxymethyl furfuraldehyde(5-HMF) groups, and a metformin(250 mg·kg~(-1)) group. In addition, a normal group was also set and each group included 8 mice. The pancreas was collected after four weeks of administration and proteomics tools were employed to study the effects of Rehmanniae Radix and Rehmanniae Radix Praeparata on protein expression in the pancreas of T2DM mice. The expression levels of proteins involved in autophagy, inflammation, and oxidative stress response in the pancreatic tissues of T2DM mice were determined by western blotting, immunohistochemical assay, and transmission electron microscopy. The results showed that the differential proteins between the model group and Rehmanniae Radix/Rehmanniae Radix Prae-parata group were enriched in 7 KEGG pathways, such as autophagy-animal, which indicated that the 7 pathways may be associated with T2DM. Compared with the control group, drug administration significantly up-regulated the expression levels of beclin1 and phosphorylated mammalian target of rapamycin(p-mTOR)/mTOR and down-regulated those of the inflammation indicators, Toll-like receptor-4(TLR4) and Nod-like receptor protein 3(NLRP3), in the pancreas of T2DM mice, and Rehmanniae Radix showed better performance. In addition, the expression levels of inducible nitric oxide synthase(iNOS), nuclear factor erythroid 2-related factor 2(Nrf2), and heine oxygenase-1(HO-1) in the pancreas of T2DM mice were down-regulated after drug administration, and Rehmanniae Radix Praeparata demonstrated better performance. The results indicate that both Rehmanniae Radix and Rehmanniae Radix Praeparata can alleviate the inflammatory symptoms, reduce oxidative stress response, and increase the autophagy level in the pancreas of T2DM mice, while they exert the effect on different autophagy pathways.

Naringenin Enhances the Antitumor Effect of Therapeutic Vaccines by Promoting Antigen Cross-Presentation.

Dendritic cells (DCs) can internalize and cross-present exogenous Ags to CD8+ T cells for pathogen or tumor cell elimination. Recently, growing evidences suggest the possible immunoregulatory role of flavonoids through modulating the Ag presentation of DCs. In this study, we report that naringenin, a grapefruit-derived flavonoid, possesses the ability to increase the Ag cross-presentation in both murine DC line DC2.4 as well as bone marrow-derived DCs, and naringenin-induced moderate intracellular oxidative stress that contributed to the disruption of lysosomal membrane enhanced Ag leakage to cytosol and cross-presentation. Moreover, in a murine colon adenocarcinoma model, naringenin induced more CD103+ DCs infiltration into tumor and facilitated the activation of CD8+ T cells and strengthened the performance of therapeutic E7 vaccine against TC-1 murine lung cancer. Our investigations may inspire novel thoughts for vaccine design and open a new field of potential applications of flavonoids as immunomodulators to improve host protection against infection and tumor.

Amorphous RuS2 electrocatalyst with optimized active sites for hydrogen evolution.

Transition metal chalcogenides have attracted much attention as high-performance electrocatalysts for hydrogen evolution reaction (HER). Here, we synthesized an efficient HER electrocatalyst of amorphous ruthenium sulfide (A-RuS2), exhibiting an overpotential of 141 mV at the current density of 10 mA cm-2 and a Tafel slope of 65.6 mV dec-1. Experiments demonstrate amorphous RuS2 has much better catalytic activity than that of its crystalline counterparts. Our study shows that amorphous RuS2 has increased intrinsic activity and active sites. This work provides a feasible strategy for the development of HER electrocatalysts in amorphous state.

Naringenin Ameliorates Acute Inflammation by Regulating Intracellular Cytokine Degradation.

Ungoverned activation of innate and adaptive immunity results in acute inflammatory disease, such as bacteria-induced endotoxemia and fulminant hepatitis by virus infection. Thus, therapeutic control of inflammation is crucial for clinical management of many human diseases. In murine models of LPS- and Con A-induced liver injury, we found that naringenin, a natural predominant flavanone, is capable of protecting against lethality induced by LPS and preventing inflammation-induced organ injury. The protective effect of naringenin is mediated by reducing the levels of several inflammatory cytokines. Unexpectedly, naringenin inhibits TNF-α and IL-6 secretion in macrophages and T cells without interfering with the TLR signaling cascade, cytokine mRNA stability, or protein translation. These results indicate the existence of a posttranslational control mechanism. Further studies show that naringenin enhances intracellular cytokine degradation through lysosome- and TFEB-dependent mechanisms. This study provides evidence that naringenin has the capacity to dampen cytokine production by regulating lysosome function. Thus, naringenin may represent a potential therapeutic agent for controlling inflammation-related diseases.

Naringenin Ameliorates Radiation-Induced Lung Injury by Lowering IL-1ß Level.

Radiation-induced lung injury (RILI) is the main complication of radiotherapy for thoracic malignancies. Since naringenin, a potent immune-modulator, has been found to relieve bleomycin-induced lung fibrosis by restoring the balance of disordered cytokines, we sought to determine whether naringenin would mitigate RILI and to investigate the underlying mechanism. Animals received fractionated irradiation in the thoracic area to induce RILI. Enzyme-linked immunosorbent assay and MILLIPLEX assays were used for serum and bronchoalveolar lavage fluid for cytokine analyses, hematoxylin and eosin staining for pathologic changes, and Masson trichrome staining for determination of lung fibrosis. Interleukin (IL)-1ß was found significantly elevated after thoracic irradiation and it triggered production of profibrotic tumor growth factor ß both in vivo and in vitro, suggesting the vital role of in IL-1ß in the development of RILI. Furthermore, we found that naringenin was able to ameliorate RILI through downregulation of IL-1ß and restoration of the homeostasis of inflammatory factors. Our results demonstrated that naringenin could serve as a potent immune-modulator to ameliorate RILI. More importantly, we suggest that a new complementary strategy of maintaining the homeostasis of inflammatory factors combined with radiation could improve the efficacy of thoracic radiotherapy.

Naringenin as a potential immunomodulator in therapeutics.

Naringenin, a citrus flavonoid that possesses various biological activities, has emerged as a potential therapeutic agent for the management of a variety of diseases. Studies using cell culture system have shown that naringenin can inhibit inflammatory response in diverse cell types. Moreover, research using various animal models has further demonstrated therapeutic potentials of naringenin in the treatment of several inflammation-related disorders, such as sepsis, fulminant hepatitis, fibrosis and cancer. The mechanism of action of naringenin is not completely understood but recent mechanistic studies revealed that naringenin suppresses inflammatory cytokine production through both transcriptional and post-transcriptional mechanisms. Surprisingly, naringenin not only inhibits cytokine mRNA expression but also promotes lysosome-dependent cytokine protein degradation. This unique property of naringenin stands in sharp contrast with some widely-studied natural products such as apigenin and curcumin, which regulate cytokine production essentially at the transcriptional level. Therefore, naringenin may provide modality for the development of novel anti-inflammatory agent. This review article summarizes our recent studies in understanding how naringenin acts in cells and animal models. Particularly, we will discuss the anti-inflammatory activities of naringenin in various disease context and its potential use, as an immunomodulator, in the treatment of inflammatory related disease.

Naringenin prevents TGF-ß1 secretion from breast cancer and suppresses pulmonary metastasis by inhibiting PKC activation.

BACKGROUND: Targeting the TGF-ß1 pathway for breast cancer metastasis therapy has become an attractive strategy. We have previously demonstrated that naringenin significantly reduced TGF-ß1 levels in bleomycin-induced lung fibrosis and effectively prevented pulmonary metastases of tumors. This raised the question of whether naringenin can block TGF-ß1 secretion from breast cancer cells and inhibit their pulmonary metastasis. METHODS: We transduced a lentiviral vector encoding the mouse Tgf-ß1 gene into mouse breast carcinoma (4T1-Luc2) cells and inoculated the transformant cells (4T1/TGF-ß1) into the fourth primary fat pat of Balb/c mice. Pulmonary metastases derived from the primary tumors were monitored using bioluminescent imaging. Spleens, lungs and serum (n = 18-20 per treatment group) were analyzed for immune cell activity and TGF-ß1 level. The mechanism whereby naringenin decreases TGF-ß1 secretion from breast cancer cells was investigated at different levels, including Tgf-ß1 transcription, mRNA stability, translation, and extracellular release. RESULTS: In contrast to the null-vector control (4T1/RFP) tumors, extensive pulmonary metastases derived from 4T1/TGF-ß1 tumors were observed. Administration of the TGF-ß1 blocking antibody 1D11 or naringenin showed an inhibition of pulmonary metastasis for both 4T1/TGF-ß1 tumors and 4T1/RFP tumors, resulting in increased survival of the mice. Compared with 4T1/RFP bearing mice, systemic immunosuppression in 4T1/TGF-ß1 bearing mice was observed, represented by a higher proportion of regulatory T cells and myeloid-derived suppressor cells and a lower proportion of activated T cells and INFγ expression in CD8(+) T cells. These metrics were improved by administration of 1D11 or naringenin. However, compared with 1D11, which neutralized secreted TGF-ß1 but did not affect intracellular TGF-ß1 levels, naringenin reduced the secretion of TGF-ß1 from the cells, leading to an accumulation of intracellular TGF-ß1. Further experiments revealed that naringenin had no effect on Tgf-ß1 transcription, mRNA decay or protein translation, but prevented TGF-ß1 transport from the trans-Golgi network by inhibiting PKC activity. CONCLUSIONS: Naringenin blocks TGF-ß1 trafficking from the trans-Golgi network by suppressing PKC activity, resulting in a reduction of TGF-ß1 secretion from breast cancer cells. This finding suggests that naringenin may be an attractive therapeutic candidate for TGF-ß1 related diseases.

From Xiaoke to diabetes mellitus: a review of the research progress in traditional Chinese medicine for diabetes mellitus treatment.

Diabetes mellitus (DM) is a chronic metabolic disorder characterized by hyperglycemia resulting from insulin secretion defects or insulin resistance. The global incidence of DM has been gradually increasing due to improvements in living standards and changes in dietary habits, making it a major non-communicable disease that poses a significant threat to human health and life. The pathogenesis of DM remains incompletely understood till now, and current pharmacotherapeutic interventions are largely inadequate, resulting in relapses and severe adverse reactions. Although DM is not explicitly mentioned in traditional Chinese medicine (TCM) theory and clinical practice, it is often classified as "Xiaoke" due to similarities in etiology, pathogenesis, and symptoms. With its overall regulation, multiple targets, and personalized medication approach, TCM treatment can effectively alleviate the clinical manifestations of DM and prevent or treat its complications. Furthermore, TCM exhibits desirable therapeutic effects with minimal side effects and a favorable safety profile. This paper provides a comprehensive comparison and contrast of Xiaoke and DM by examining the involvement of TCM in their etiology, pathogenesis, treatment guidelines, and other relevant aspects based on classical literature and research reports. The current TCM experimental research on the treatment of DM by lowering blood glucose levels also be generalized. This innovative focus not only illuminates the role of TCM in DM treatment, but also underscores the potential of TCM in DM management.

Enhanced electrocatalytic performance of N-doped carbon xerogels obtained through dual nitrogen doping for the oxygen reduction reaction.

The development of high efficiency and low-cost electrocatalysts for the oxygen reduction reaction (ORR) is urgently desired for many energy storage and conversion systems. Nitrogen-doped carbon xerogels (NCXs) which have been successfully applied as effective electrocatalysts for the ORR have continued to attract attention due to their competitive price and tunable surface chemistry. A new dual N-doped NCX (NCoNC) electrocatalyst is fabricated as a carbon based catalyst though a facile impregnation of peptone in a precursor and ammonia etching pyrolysis method. XPS analysis demonstrates that the NCoNC electrocatalyst not only has a high N doping amount, but also has an optimized chemical state composition of N doping, which play an important role in improving the microstructure and catalytic performance of the catalysts. XRD and HRTEM results show that the doped metal nano-particles are coated with a double carbon layer of graphene carbon (inner layer) and amorphous carbon (outer layer) forming serrated edges that facilitate the ORR process. The as-obtained NCoNC catalyst exhibits good electrocatalytic performance and excellent stability for the ORR in both acidic and alkaline environments. In particular, in alkaline electrolyte, the decrements of both the limiting current density and the half-wave potential of the NCoNC catalyst were significantly lower than those of a commercial Pt/C catalyst during accelerated aging tests. When serving as an air electrode in Zn-air batteries, the catalyst also exhibits superior catalytic performance with a peak power density of 78.2 mW cm-2 and a stable open-circuit voltage of 1.37-1.43 V. This work presents a novel tactic to regulate the microstructure and composition of carbon-based electrocatalysts by the facile and scalable dual-effect nitrogen doping method which may be conducive to promoting and developing highly efficient and promising electrocatalysts for the ORR.

Optimal combination treatment regimens of vaccine and radiotherapy augment tumor-bearing host immunity.

A major obstacle to immunotherapy is insufficient infiltration of effector immune cells into the tumor microenvironment. Radiotherapy greatly reduces tumor burden but relapses often occur. Here we show that the immunosuppressive tumor microenvironment was gradually established by recruiting Tregs after radiation. Despite tumors being controlled after depletion of Tregs in the irradiated area, improvement of mice survival remained poor. A much better antitumor effect was achieved with vaccination followed by radiation than other treatments. Vaccination followed by radiation recruited more effector T cells in tumor regions, which responded to high levels of chemokines. Sequential combination of vaccination and radiotherapy could elicit distinct host immune responses. Our study demonstrated that optimal combination of irradiation and vaccination is required to achieve effective antitumor immune responses. We propose a combination regimen that could be easily translated into the clinic and offer an opportunity for rational combination therapies design in cancer treatment.

PPARα Inhibition Overcomes Tumor-Derived Exosomal Lipid-Induced Dendritic Cell Dysfunction.

Dendritic cells (DCs) orchestrate the initiation, programming, and regulation of anti-tumor immune responses. Emerging evidence indicates that the tumor microenvironment (TME) induces immune dysfunctional tumor-infiltrating DCs (TIDCs), characterized with both increased intracellular lipid content and mitochondrial respiration. The underlying mechanism, however, remains largely unclear. Here, we report that fatty acid-carrying tumor-derived exosomes (TDEs) induce immune dysfunctional DCs to promote immune evasion. Mechanistically, peroxisome proliferator activated receptor (PPAR) α responds to the fatty acids delivered by TDEs, resulting in excess lipid droplet biogenesis and enhanced fatty acid oxidation (FAO), culminating in a metabolic shift toward mitochondrial oxidative phosphorylation, which drives DC immune dysfunction. Genetic depletion or pharmacologic inhibition of PPARα effectively attenuates TDE-induced DC-based immune dysfunction and enhances the efficacy of immunotherapy. This work uncovers a role for TDE-mediated immune modulation in DCs and reveals that PPARα lies at the center of metabolic-immune regulation of DCs, suggesting a potential immunotherapeutic target.

Large-Grained Cu2BaSnS4 Films for Photocathodes.

p-Type compounds Cu2BaSnS4 (CBTS) are extremely attractive materials for photocathode applications because of their suitable conduction and valence bands, earth-abundant sources, and environmental friendly nature. Herein, an inexpensive and reproducible aqueous solution approach has been developed to synthesize CBTS films with single-crystalline grains as large as micron scale. Because of the large crystalline grains, the as-grown CBTS films show excellent carrier mobility (1.29 cm2/V·s). Greater than 4 mA·cm-2 photocurrent density has been obtained in a neutral solution for bare Mo/CBTS film photocathodes under 100 mW·cm-2 illumination at 0 V versus reversible hydrogen electrode.

An aqueous solution method towards Sb2S3 thin films for photoanodes.

An aqueous solution approach, integrating atomic layer deposition and chemical vapor deposition, is proposed to grow a high-quality Sb2S3 thin film. The Sb2S3 thin film is uniform and dense with a bandgap of 1.78 eV. The photocurrent density of the Sb2S3 sensitized TiO2 array electrode is 40 µA cm-2, which is nearly 25 and 93 times than that of TiO2 and Sb2S3 photoanodes, respectively.

Lysosome-oriented, dual-stage pH-responsive polymeric micelles for ß-Lapachone delivery.

ß-Lapachone (ß-lap), a novel anticancer agent, is bioactivated by NADP(H):quinone oxidoreductase 1 (NQO1), an enzyme over-expressed in numerous tumors, including lung, pancreas, breast, and prostate cancers. Fast renal clearance and methemaglobinemia / hemolytic side-effects from the clinical formulation (ß-lap-hydroxyl propyl-ß-cyclodextrin complex) hindered its clinical translation. Here, we investigated a dual model pH responsive polymers for ß-lap delivery. Three pH-sensitive linkages, including acylhydrazone, ketal and imine bonds for ß-lap prodrug syntheses result in an aryl imine linkage the most optimal linkage. The conversion to ß-lap was 2.8%, 4.5% and 100% at pH 7.4, 6.5 and 5.0 in 8 h, respectively. ß-lap aryl imine prodrug conjugated ultra pH-sensitive (UPS) polymer reached high ß-lap loading density (8.3%) and exhibited dual-stages responsiveness to pH variation. In pHs under pHt, at stage I, micelle immediately dissociation and subsequently entering stage II, micelles start quickly release ß-lap. In vitro release study showed that the micelles constantly release ß-lap (14.9 ± 0.1%) at pHs above pHt in 72 h, whereas boosted release of ß-lap (79.4 ± 1.2%) at pH 5.0. Micelle intracellular distribution predominantly in the lysosome organelle guaranteed their pH responsive dissociation and subsequently ß-lap controlled release. The M-P micelles retained NQO1-dependent cytotoxicity in A549 lung cancer cells, similar to free drug in both efficacy and mechanism of cell death. The lysosome-oriented dual-stage ultra pH responsive ß-lap prodrug micelles potentially offer an alternative nanotherapeutic strategy for lung, as well as other NQO1+ cancer therapies.

Single-Molecule Imaging Reveals the Activation Dynamics of Intracellular Protein Smad3 on Cell Membrane.

Smad3 is an intracellular protein that plays a key role in propagating transforming growth factor ß (TGF-ß) signals from cell membrane to nucleus. However whether the transient process of Smad3 activation occurs on cell membrane and how it is regulated remains elusive. Using advanced live-cell single-molecule fluorescence microscopy to image and track fluorescent protein-labeled Smad3, we observed and quantified, for the first time, the dynamics of individual Smad3 molecules docking to and activation on the cell membrane. It was found that Smad3 docked to cell membrane in both unstimulated and stimulated cells, but with different diffusion rates and dissociation kinetics. The change in its membrane docking dynamics can be used to study the activation of Smad3. Our results reveal that Smad3 binds with type I TGF-ß receptor (TRI) even in unstimulated cells. Its activation is regulated by TRI phosphorylation but independent of receptor endocytosis. This study offers new information on TGF-ß/Smad signaling, as well as a new approach to investigate the activation of intracellular signaling proteins for a better understanding of their functions in signal transduction.

Is Intracranial Pressure Monitoring of Patients With Diffuse Traumatic Brain Injury Valuable? An Observational Multicenter Study.

BACKGROUND: Although intracranial pressure (ICP) monitoring of patients with severe traumatic brain injury (TBI) is recommended by the Brain Trauma Foundation, any benefits remain controversial. OBJECTIVE: To evaluate the effects of ICP monitoring on the mortality of and functional outcomes in patients with severe diffuse TBI. METHODS: Data were collected on patients with severe diffuse TBI (Glasgow Coma Scale [GCS] score on admission <9 and Marshall Class II-IV) treated from January 2012 to December 2013 in 24 hospitals (17 level I trauma centers and 7 level II trauma centers) in 9 Chinese provinces. We evaluated the impact of ICP monitoring on 6-month mortality and favorable outcome using propensity score-matched analysis after controlling for independent predictors of these outcomes. RESULTS: ICP monitors were inserted into 287 patients (59.5%). After propensity score matching, ICP monitoring significantly decreased 6-month mortality. ICP monitoring also had a greater impact on the most severely injured patients on the basis of head computed tomography data (Marshall computed tomography classification IV) and on patients with the lowest level of consciousness (GCS scores 3-5). After propensity score matching, monitoring remained nonassociated with a 6-month favorable outcome for the overall sample. However, monitoring had a significant impact on the 6-month favorable outcomes of patients with the lowest level of consciousness (GCS scores 3-5). CONCLUSION: ICP monitor placement was associated with a significant decrease in 6-month mortality after adjustment for the baseline risk profile and the monitoring propensity of patients with diffuse severe TBI, especially those with GCS scores of 3 to 5 or of Marshall computed tomography classification IV.

Establishment of an orthotopic transplantation tumor model in nude mice using a drug-resistant human ovarian cancer cell line with a high expression of c-Kit.

The resistance of ovarian cancer to platinum-based chemotherapy is a critical issue in the clinical setting. The present study aimed to establish animal models to replicate this clinical condition, as well as to investigate the resistance mechanisms of ovarian cancer. A cisplatin (DDP)-resistant human ovarian cancer cell line, SKOV3/DDP, was screened, validated and injected subcutaneously into the neck of female nude mice. Following tumor establishment, the tumor was collected and cut into small sections, which were subsequently implanted into the ovaries of other nude mice. The growth of the orthotopic tumors was observed and the tumor-bearing mice were sacrificed and dissected. The orthotopic and metastatic tumor tissues were collected, sectioned, stained with hematoxylin and eosin and analyzed. In the present study, 16 nude mice underwent orthotopic transplantation surgery and a tumor model was successfully established in 14/16 of the mice, with an in situ tumor formation rate of 87.5%. Following euthanasia, a laparotomy demonstrated the tumor formation at the site of transplantation, as well as varying degrees of metastasis to additional organs and tissues. Therefore, the present study successfully established an orthotopic tumor transplantation model in nude mice using a c-Kit-positive DDP-resistant human ovarian cancer cell line. This model may represent a useful tool for investigating the resistance mechanism of ovarian cancer, as well as evaluating the efficacy of therapeutic strategies.

Methodologies for the establishment of an orthotopic transplantation model of ovarian cancer in mice.

This study used different methods to establish an animal model of orthotopic transplantation for ovarian cancer to provide an accurate simulation of the mechanism by which tumor occurs and develops in the human body. We implanted 4T1 breast cancer cells stably-transfected with luciferase into BALB/c mice by using three types of orthotopic transplantation methodologies: (1) cultured cells were directly injected into the mouse ovary; (2) cell suspension was initially implanted under the skin of the mouse neck; after tumor mass formed, the tumor was removed and ground into cell suspension, which was then injected into the mouse ovary; and (3) a subcutaneous tumor mass was first generated, removed, and cut into small pieces, which were directly implanted into the mouse ovary. After these models were established, in vivo luminescence imaging was performed. Results and data were compared among groups. Orthotopic transplantation model established with subcutaneous tumor piece implantation showed a better simulation of tumor development and invasion in mice. This model also displayed negligible response to artificial factors. This study successfully established an orthotopic transplantation model of ovarian cancer with high rates of tumor formation and metastasis by using subcutaneous tumor pieces. This study also provided a methodological basis for future establishment of an animal model of ovarian cancer in humans.

A dual character of flavonoids in influenza A virus replication and spread through modulating cell-autonomous immunity by MAPK signaling pathways.

Flavonoids are well known as a large class of polyphenolic compounds, which have a variety of physiological activities, including anti-influenza virus activity. The influenza A/WSN/33 infected A549 cells have been used to screen anti-influenza virus drugs from natural flavonoid compounds library. Unexpectedly, some flavonoid compounds significantly inhibited virus replication, while the others dramatically promoted virus replication. In this study, we attempted to understand these differences between flavonoid compounds in their antivirus mechanisms. Hesperidin and kaempferol were chosen as representatives of both sides, each of which exhibited the opposite effects on influenza virus replication. Our investigation revealed that the opposite effects produced by hesperidin and kaempferol on influenza virus were due to inducing the opposite cell-autonomous immune responses by selectively modulating MAP kinase pathways: hesperidin up-regulated P38 and JNK expression and activation, thus resulting in the enhanced cell-autonomous immunity; while kaempferol dramatically down-regulated p38 and JNK expression and activation, thereby suppressing cell-autonomous immunity. In addition, hesperidin restricted RNPs export from nucleus by down-regulating ERK activation, but kaempferol promoted RNPs export by up-regulating ERK activation. Our findings demonstrate that a new generation of anti-influenza virus drugs could be developed based on selective modulation of MAP kinase pathways to stimulate cell-autonomous immunity.