Anlotinib reduces the suppressive capacity of monocytic myeloid-derived suppressor cells and potentiates the immune microenvironment normalization window in a mouse lung cancer model.

By exploring the effects of an antiangiogenic small molecule drug named anlotinib on the levels of myeloid-derived suppressor cells (MDSCs) in a mouse xenograft model of lung cancer, the role of anti-angiogenesis in remodeling the immune microenvironment was discussed. In addition, the impact of anlotinib on the normalization of the immune microenvironment and time window was examined, providing a theoretical basis for the optimization of clinical strategies applying anlotinib combined with PD-1 inhibitors. On the basis of the LLC mouse xenograft model, MDSCs and MDSCs + immune microenvironment were examined in tissues, respectively, according to different samples. The former observation included the control (group A) and anlotinib monotherapy (group B) groups; the latter also included the control (group C) and anlotinib monotherapy (group D) groups. The levels of MDSCs in peripheral blood at different time points were analyzed by flow cytometry, and the levels of MDSCs in tissue samples at different time points were evaluated by immunofluorescence and immunohistochemistry. The volumes of subcutaneous xenografts were significantly smaller in the anlotinib treatment group compared with the control group ( P < 0.005). Flow cytometry showed that compared with the control group, the intratumoral percentages of total MDSCs ( P < 0.01) and mononuclear-MDSCs ( P < 0.05) were significantly decreased on days 3 and 17 after anlotinib treatment in peripheral blood samples; however, there was no significant difference in granulocytic-MDSCs changes between the experimental and control groups. Immunofluorescence showed that the levels of MDSCs in both the experimental and control groups reached the lowest points 10 days after drug administration, and were significantly lower in the experimental group than in the control group ( P < 0.05). Anlotinib reduces the levels of MDSCs in the mouse xenograft model of lung cancer, with the characteristics of time window. This study provides a basis for further exploring strategies for anti-angiogenic treatment combined with immunotherapy in lung cancer based on time-window dosing.

Induction versus adjuvant chemotherapy combined with concurrent chemoradiotherapy in locoregionally advanced nasopharyngeal carcinoma: a retrospective cohort study.

BACKGROUND: Currently available evidence favors the combination of chemotherapy with concurrent chemoradiotherapy in locoregionally advanced nasopharyngeal carcinoma (LANPC). However, the optimal timing for additional chemotherapy is unclear. This study was conducted to compare the efficacy and toxicity of induction chemotherapy plus concurrent chemoradiotherapy (IC+CCRT) versus concurrent chemoradiotherapy plus adjuvant chemotherapy (CCRT+AC). METHODS: Two medical centers in China enrolled patients with LANPC (stage III-IVB) between January 2009 and May 2020. Through the use of propensity score matching (PSM), baseline characteristics were balanced. The primary endpoint was overall survival (OS), which was evaluated by the Kaplan-Meier method and log-rank test. Potential independent prognostic factors were identified using univariate and multivariate Cox proportional hazard analyses. Based on the chi-squared test, we compared the adverse events associated with treatment between the groups. RESULTS: After the implementation of PSM, 159 patients treated with IC+CCRT and 72 patients treated with CCRT+AC were eventually enrolled in this study. There was no significant difference between patients treated with IC+CCRT and CCRT+AC in terms of 3-year OS (94.7% versus 90.9%, p=0.816), progression-free survival (PFS) (91.2% versus 83.1%, p=0.588), locoregional recurrence-free survival (LRFS) (92.5% versus 81.8%, p=0.478), or distant metastasis-free survival (DMFS) (93.4% versus 88.2%, p=0.783). There was no prognostic significance of the treatment for OS, PFS, LRFS, or DMFS (all p > 0.05) in the univariate and multivariate analyses. Patients treated with CCRT+AC had a higher incidence of grade 3 to 4 leucopenia (p=0.001) and neutropenia (p=0.001) than those treated with IC+CCRT. CONCLUSIONS: IC plus CCRT achieved comparable survival outcomes to CCRT plus AC and had a lower incidence of toxicity.

Induction of ligustrazine apoptosis of A549 cells through activation of death receptor pathway.

Background: The aim of this study was to evaluate the effect of ligustrazine on the apoptosis of A549 cells and clarify the mechanism of ligustrazine-induced apoptosis. Methods: Ligustrazine was prepared with medium according to the gradient concentration. Based on a cytotoxicity test, 3 different concentrations of ligustrazine were selected to form low, medium, and high groups, with a 0 mg/mL dose used as the control. The apoptosis degree and Fas (Fas cell surface death receptor) and Fas-L (Fas Ligand) expression were detected by flow cytometry and quantitative polymerase chain reaction (qPCR), respectively; meanwhile, the activity of caspase 8 and caspase 3 was analyzed by enzyme-linked immunosorbent assay (ELISA) and qPCR, respectively. Results: After 24 hours of ligustrazine administration, the survival rate of A549 cells decreased with the increase of drug concentration, while the rate of apoptosis increased with the increase of drug concentration. Meanwhile, Fas and Fas-L expression was found to be significantly increased at both the gene and protein level, which was positively correlated with drug concentration. Furthermore, the expression of caspase 8 and caspase 3 was positively correlated with the concentration of ligustrazine, and there was significant difference compared with the control group. Conclusions: Ligustrazine can induce the apoptosis of A549 cells via the upregulation of Fas- and caspase-activating death receptor pathway expression.

Evaluation of response to stereotactic body radiation therapy for nonsmall cell lung cancer: PET response criteria in solid tumors versus response evaluation criteria in solid tumors.

OBJECTIVE: Recommendations for surveillance after stereotactic body radiation therapy (SBRT) for early-stage nonsmall cell lung cancer (NSCLC) are not well defined. Recently, PET response criteria in solid tumors (PERCIST) have been proposed as a new standardized method to assess radiotherapeutic response both quantitatively and metabolically. The aim of this study was to evaluate therapeutic response following SBRT in early-stage NSCLC patients by comparing PERCIST with the currently widely used RECIST. MATERIALS AND METHODS: Forty-nine patients with early-stage NSCLC who had been prescribed SBRT were studied. Responses of lesion were evaluated using CT and 18F-FDG PET according to the RECIST and PERCIST methods. PET-CT scans were obtained before SBRT and 3-6 months after SBRT. Associations between overall survival (OS) and clinicopathologic results (histology, tumor location, tumor size, lymphatic invasion, clinical stage, and radiotherapeutic responses in RECIST and PERCIST) were statistically analyzed. The median patient follow-up was 30 months. RESULTS: Thirteen patients had stage IA, 9 stage IB, 10 stage IIA, and 17 stage IIB biopsy-proven NSCLC. Three-year OS was 79.6%. CT scans indicated three regional recurrences. PET-CT/chest indicated three regional recurrences and distant metastasis. Significant differences were observed in response classification between RECIST and PERCIST (Wilcoxon signed-rank test, P = 0.0041). Univariate analysis showed that clinical stage, RECIST, and PERCIST were significant factors associated with OS, whereas by multivariate analysis PERCIST was the only predictor of OS. SMD, PMD/PMR, and CMR in PERCIST criteria were indicative of a 9.900-fold increase in the risk of OS in early NSCLC patients [risk ratio, 9.900 (95% CI, 1.040-21.591); P = 0.001]. CONCLUSION: RECIST based on the anatomic size reduction rate did not demonstrate the correlation between radiotherapeutic response and prognosis in patients with early-stage NSCLC receiving SBRT. However, PERCIST was shown as the strongest independent predictor of outcomes. PERCIST might be considered more suitable for the evaluation of NSCLC tumor response to SBRT than RECIST.

HSP90 promotes radioresistance of cervical cancer cells via reducing FBXO6-mediated CD147 polyubiquitination.

HSP90 inhibition might be a promising strategy to overcome the radioresistance of some cancers. In the current study, we further explored the mechanisms of HSP90 in regulating the radiosensitivity of cervical cancer cells. Bioinformatic analysis was performed based on data from TCGA-CESC. Cellular and molecular studies were conducted using CaSki and SiHa and the derived radioresistant (RR) subclones. Through a proteomics screen, we identified HSP90 chaperones (both HSP90α and HSP90ß) as CD147-binding partners supporting its stabilization. Targeting HSP90 sensitized CaSki-RR and SiHa-RR cancer cells to irradiation partially through CD147 destabilization. Mechanistically, HSP90 interacts with FBXO6 and reduces FBXO6-mediated proteasomal degradation of CD147. Enforced FBXO6 overexpression also sensitized CaSki-RR and SiHa-RR cancer cells to irradiation. These effects were enhanced using 17-AAG treatment but were weakened by CD147 overexpression. Survival analysis further confirmed the association between high FBXO6 expression and favorable progression-free survival among patients with cervical cancer. In conclusion, this study showed that HSP90 promotes radioresistance of cervical cancer cells partially via reducing FBXO6 mediated CD147 polyubiquitination. These findings help to explain why HSP90 inhibitor exerts radio-sensitizing effects in cervical cancer.

[Flubendazole Inhibits the Proliferation of A549 and H460 Cells and Promotes Autophagy].

BACKGROUND: Flubendazole is an anthelmintic and categorized in benzimidazole. Previous evidence indicates its suppression on proliferation of colon cancer and breast cancer cells. Our study aims to explore the effects of flubendazole on non-small cell lung cancer A549 and H460 cell lines and the underlying mechanism. METHODS: CCK-8 assay was used to detect the effect of flubendazole at different concentrations on viability of both cell lines A549 and H460. We used western blot to detect the expression levels of autophagy-related proteins p62 and LC3 after flubendazole treatment. Cells were transfected with tandem fluorescent adenovirus (mRFP-GFP-LC3), and the impact of flubendazole treatment on autophagic flux were analyzed. RESULTS: Cell viability analysis showed a dose-dependent inhibitory effect on proliferation of both A549 and H460, comparing to cells without flubendazole treating (P<0.001). Level of p62 decreased and LC3 II/I ratio increased in cells treated with 2 µmol/L flubendazole for 24 h and 48 h, compared to control groups (P<0.005). Red fluorescence signals increased in mRFP-GFP-LC3 transfected cells after flubendazole treating, suggesting an elevation in autophagic flux. CONCLUSIONS: Flubendazole may inhibit the proliferation of A549 and H460 cells and promote autophagy.

[Preparation and identification of monoclonal antibodies against chicken cell cycle checkpoint kinase 2 (cChk2)].

Objective To prepare monoclonal antibodies (mAbs) against chicken cell cycle checkpoint kinase 2 (cChk2). Methods The cChk2 gene was amplified by reverse transcription PCR (RT-PCR) and subcloned into the prokaryotic expression vector pGEX-4T-3. After induced by IPTG, cChk2 was expressed in BL21 (DE3) E.coli cells and analyzed by SDS-PAGE to determine its soluability. BALB/c mice were immunized with cChk2 protein peritoneally. Indirect immunofluorescence assay (IFA) and Western blotting were used to detect anti-serum; if the detection result was positive, IFA and limited dilution was performed to screen hybridoma clones that produced antibodies against cChk2. Results cChk2 was mainly expressed in inclusion bodies. The anti-sera were able to recognize Chk2. Nine positive hybridoma clones were obtained and identified as 1F4, 2D9, 2G1, 3D9, 3E3, 4B5, 4E2, 5C9 and 5F7. Conclusion The study has prepared mAbs against cChk2 with a good specificity and a high titer.

Metabolism-related enzyme alterations identified by proteomic analysis in human renal cell carcinoma.

The renal cell carcinoma (RCC) is one of the most common types of kidney neoplasia in Western countries; it is relatively resistant to conventional chemotherapy and radiotherapy. Metabolic disorders have a profound effect on the degree of malignancy and treatment resistance of the tumor. However, the molecular characteristics related to impaired metabolism leading to the initiation of RCC are still not very clear. In this study, two-dimensional electrophoresis (2-DE) and mass spectra (MS) technologies were utilized to identify the proteins involved in energy metabolism of RCC. A total of 73 proteins that were differentially expressed in conventional RCC, in comparison with the corresponding normal kidney tissues, were identified. Bioinformatics analysis has shown that these proteins are involved in glycolysis, urea cycle, and the metabolic pathways of pyruvate, propanoate, and arginine/proline. In addition, some were also involved in the signaling network of p53 and FAS. These results provide some clues for new therapeutic targets and treatment strategies of RCC.

Clinical value of 18F-fluorodeoxyglucose positron emission tomography/computed tomography in evaluating relapsed and refractory nasopharyngeal carcinoma: A case report.

For patients with locoregionally advanced nasopharyngeal carcinoma (NPC), radiotherapy, chemotherapy and even targeted therapy are widely accepted treatments. These treatments, although they mostly achieve locoregional tumor control, they may also be associated with complex post-treatment changes, such as edema, loss of tissue planes, fibrosis, mucositis and scarring, which may interfere with the detection of local recurrence and the response to therapy. However, timely detection is crucial for deciding whether treatment modification or discontinuation is required. This is the case report of A 51-year-old nasopharyngeal carcinoma patient with cervical nodal metastases (CNM). Following radiotherapy, chemotherapy and targeted therapy, multislice spiral enhanced computed tomography (CT), enhanced magnetic resonance imaging (MRI) and 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET)/CT of the neck were performed to compare the extent of the CNM. The enhanced CT and MRI images were unremarkable, whereas the 18F-FDG PET/CT images revealed the exact recurrence or remission. Therefore, 18F-FDG PET/CT exhibits a better sensitivity and specificity for evaluating the response to combined treatment compared to CT and/or MRI.

Growth inhibitory effect of adenovirus-mediated tissue-targeted expression of ribosomal protein L23 on human colorectal carcinoma cells.

A large body of evidence has established murine double minute 2 (MDM2) as a crucial negative regulator of p53 and the major suppressor of p53 function in tumors with wild-type (wt)-p53. Therefore, by inhibiting MDM2 one may reactivate p53 in tumor cells, leading to their demise. Previous studies revealed that ribosomal protein L23 (RPL23) inhibited MDM2-mediated p53 ubiquitination through direct binding to MDM2, and subsequently induced the p53 level as well as its activity, suggesting that it may be a candidate for use in tumor gene therapy. In the present study, we developed a recombinant adenoviral vector expressing the RPL23 gene under control of the carcinoembryonic antigen (CEA) promoter (rAd/CEA-RPL23), and using an in vitro system with cultured human colorectal carcinoma LoVo cells harboring the wt-p53 gene, we proved that rAd/CEA-RPL23 infection could induce the accumulation of endogenous wt-p53 protein and thus lead to the inhibition of tumor cell growth via inducing cell cycle arrest and apoptosis. In vivo treatment of rAd/CEA-RPL23 also exhibited a significant inhibitory effect on tumor growth in nude mice bearing LoVo xenografts. Furthermore, we showed that rAd/CEA-RPL23 synergized with classic chemotherapeutic agent 5-fluorouracil (5-FU) and enhanced its activity against LoVo cells in vivo and in vitro. Taken together, the data presented here suggest that CEA promoter-targeted exogenous RPL23 expression could be of therapeutic value against human colorectal carcinoma that retains wt-p53.

Comparative proteomic analysis of anti-cancer mechanism by periplocin treatment in lung cancer cells.

BACKGROUND: Periplocin is used for treatment of rheumatoid arthritis, reinforcement of bones and tendons, palpitations or shortness of breath and lower extremity edema in traditional medicine. Our previous findings suggested that periplocin could inhibit the growth of lung cancer both in vitro and in vivo. But the biological processes and molecular pathways by which periplocin induces these beneficial effects remain largely undefined. METHODS: To explore the molecular mechanisms of periplocin involved in anti-cancer activity, in the present study the protein profile changes of human lung cancer cell lines A549 in response to periplocin treatment were investigated using the proteomics approaches (2-DE combined with MS/MS). Western blot was employed to verify the changed proteins. Interactions between changed proteins were analyzed by STRING. RESULTS: 29 down-regulated protein species named GTP-binding nuclear protein Ran (RAN), Rho GDP-dissociation inhibitor 1 (ARHGDIA), eukaryotic translation initiation factor 5A-1 (EIF5A) and Profilin-1(PFN1), and 10 up-regulated protein species named Heat shock cognate 71 kDa protein (HSPA8),10 kDa heat shock protein (HSPE1), and Cofilin-1(CFL-1) were identified. Among them, GTP-binding nuclear protein Ran (RAN) and Rho GDP-dissociation inhibitor 1 (ARHGDIA) were the most significantly changed (over tenfold). The proteasome subunit beta type-6 (PSMB6), ATP synthase ecto-α-subunit (ATP5A1), Aldehyde dehydrogenase 1 (ALDH1) and EIF5A were verified by immunoblot assays to be dramatically down-regulated. By STRING bioinformatics analysis revealing interactions and signaling networks it became apparent that the proteins changed they are primarily involved in transcription and proteolysis. CONCLUSION: Periplocin inhibited growth of lung cancer by down-regulating proteins, such as ATP5A1, EIF5A, ALDH1 and PSMB6. These findings may improve our understanding of the molecular mechanisms underlying the anti-cancer effects of periplocin on lung cancer cells.

Bioinformatic analysis of the membrane cofactor protein CD46 and microRNA expression in hepatocellular carcinoma.

The therapeutic potential of membrane complement regulatory protein (mCRP)-neutralizing antibodies is unsatisfactory, which perhaps lies in the complex role of mCRPs in tumor occurrence and development. As a member of the mCRPs, CD46 is a transmembrane protein with a cytoplasmic domain and is implicated more in the control of the alternative complement pathway than of the classical complement pathway. Growing evidence has revealed that both the CD46 signaling pathway and microRNAs (miRNAs) play an important role in the development and progression of hepatocellular carcinoma (HCC). In the present study, we analyzed mCRP expression in different tumor tissues by employing western blotting and qPCR. To address the potential role of miRNAs in CD46 signaling, we set out to profile miRNA expression in CD46-overexpressed and -silenced HepG2 cell lines. Furthermore, bioinformatic analysis was performed to identify downstream targets of CD46 signaling. We found that the levels of CD46 expression in HCC tissues were significantly higher compared to that in the adjacent normal tissues. After complement-related gene expression profiling and unsupervised hierarchical clustering analysis of 10 HCC tissues, a total of 37 miRNAs showed significantly different expression levels before and after CD46 expression change. By bioinformatic analysis, we identified let-7b and miR-17 as downstream targets of CD46 signaling, and that the expression levels of let-7b and miR-17 were negatively correlated with that of CD46 in HepG2 cells. The present study suggests that CD46 plays an important role in HCC carcinogenesis by regulating let-7b and miR-17.

Low-dose endostatin normalizes the structure and function of tumor vasculature and improves the delivery and anti-tumor efficacy of cytotoxic drugs in a lung cancer xenograft murine model.

INTRODUCTION: To some extent endostatin normalizes tumor vasculature. However, the optimum time window and optimum drug dose for tumor vascular normalization need to be explored. Here we investigate the effect of low-dose endostatin on the structure and function of tumor vasculature and the delivery and anti-tumor efficacy of cytotoxic drugs. METHODS: A lung cancer xenograft murine model was treated with low-dose endostatin for 10 days. The structure and function of the tumor vasculature were evaluated using various techniques. Paclitaxel was added in different schedules. RESULTS: Endostatin caused a significant reduction in microvessel density. Tumor vascular walls after endostatin treatment were better structured. Tumor blood perfusion was increased on day six after endostatin administration. On days three, six, and 10, Evans blue extravasation into the parenchyma of tumors was decreased. On days three and six, endostatin-treated mice had greater paclitaxel delivery. The time window of vascular normalization was approximately three to six days. On days one to three, and days four to six, combined therapy with paclitaxel significantly inhibited tumor growth. CONCLUSIONS: Low-dose endostatin aids normalization of tumor vasculature. This resulted in improved delivery of cytotoxic drugs to the tumor, which closely correlates with synergistic efficacy when combined with paclitaxel during the normalization window.

Proteomic analysis of the interleukin-4 (IL-4) response in hepatitis B virus-positive human hepatocelluar carcinoma cell line HepG2.2.15.

Hepatitis B virus (HBV) infection is the leading cause of liver cirrhosis and hepatocellular carcinoma worldwide. In recent decades, significant progress toward understanding the molecular virology and pathogenesis of HBV infection has been made. In addition, multiple treatment modalities have been developed for persons with HBV infection. In the present study, we demonstrated that IL-4 inhibits the expression of hepatitis B surface antigen and hepatitis B e antigen in a HBV stably transfected hepatocellular carcinoma cell line (HepG2.2.15). To reveal the anti-HBV mechanism of IL-4 by proteomics, 2-DE and MS technology were utilized to profile global changes in protein expression in HepG2.2.15 cells after IL-4 treatment. A total of 56 differentially expressed proteins were identified in IL-4-treated HepG2.2.15 cells. To find out the interaction of these changed proteins by bioinformatics, signaling network analysis with the STRING tool showed that the identified proteins are primarily involved in transcription and proteolysis. Taken together, these results offer valuable clues for understanding the molecular mechanisms of the IL-4-mediated anti-HBV response.

Effect of endostatin on preventing postoperative progression of distant metastasis in a murine lung cancer model.

AIMS AND BACKGROUND: The relapse and metastasis of cancer remain a predominant cause of death after surgical removal of the primary tumor. There is a positive linkage between the postoperative upregulation of systemic angiogenic activity and distant tumor metastasis. In the present study, we established a spontaneous metastasis model and investigated whether antiangiogenic therapy using endostatin could prevent the progression of distant metastasis after removal of the primary tumor. METHODS: Female C57BL/6 mice were implanted subcutaneously with 1 × 106 Lewis lung cancer cells. Twenty days after implantation of the cancer cells, the primary tumor was removed and the mice were randomly divided into three groups. The NS group received normal saline, the L-ES group received 3 mg/kg endostatin, and the H-ES group received 20 mg/kg endostatin intravenously daily for 10 days. The effect of endostatin on lung metastases and the survival time of the mice were observed. Flow cytometry and immunohistochemistry were carried out to assess the angiogenic activity. The serum endostatin levels in peripheral blood were measured using an enzyme-linked immunosorbent assay. RESULTS: The mean number of metastatic pulmonary nodules and the mean net lung weight in the NS, L-ES and H-ES groups was 10.2, 2.8 and 4.0, and 0.55 g, 0.31 g and 0.36 g, respectively. The difference between the NS group and the endostatin-treated groups was statistically significant (P <0.05). The endostatin-treated mice showed prolonged overall survival (P <0.05). Compared with the NS group, the endostatin-treated groups had lower levels of circulating endothelial cells in peripheral blood and showed a decrease in microvessel density in the metastatic tumors, with a more marked reduction in the L-ES group (P <0.05). The systemic presence of endostatin was gradually increased with the continued administration of endostatin to the mice. CONCLUSIONS: Antiangiogenic therapy with endostatin is effective in inhibiting the postoperative progression of distant metastasis.

Development of novel 5-fluorouracil carrier erythrocyte with pharmacokinetics and potent antitumor activity in mice bearing malignant ascites.

BACKGROUND: To investigate pharmacokinetics and potency of antitumor activity of a novel 5-fluorouracil carrier erythrocyte (RBC-FU) in mice bearing malignant ascites. METHODS: RBC-FU was synthesized with a hyperosmotic technique. The entrapment efficiency of targeted carrier erythrocytes was determined by reverse dialysis method with high-performance liquid chromatography (HPLC) for analyzing the quantity of 5-fluorouracil (5-FU). After a H22 hepatocarcinoma malignant ascites model was established in Kunming mice, 5-FU encapsulated by carrier erythrocytes (for Group A) and 5-FU solution (for Group B) at 20 mg per kg were injected into the peritoneal cavity of the mice, respectively. Blood and ascites samples were collected at different times to detect 5-FU quantity by HPLC. Body weight and survival time of mice were recorded in Group A, B and the Control Group in which mice were injected with normal saline only. RESULTS: 5-FU was effectively encapsulated into erythrocytes, with an encapsulating effect as 55 +/- 0.50%. In Group A, the maximum concentration (Cmax) and the area under curve (AUC) in peritoneal exudates were significantly higher than those of Group B (P < 0.05). On the other hand, 5-FU level in serum was significantly lower than that in peritoneal exudates of Group A and B (P < 0.05). High drug levels in the abdominal cavity in Group A were maintained longer than those in Group B. Compared with that in Group B and the control, the quantity of malignant ascites in Group A had significant regression and the survival time was prolonged. CONCLUSION: The hyperosmotic method described here could be suitable for producing this novel RBC-FU as a liposomal drug of potential value for treating malignant ascites by intraperitoneal administration.

Proteomic analysis of interstitial fluid in bone marrow identified that peroxiredoxin 2 regulates H(2)O(2) level of bone marrow during aging.

Hematopoiesis in bone marrow declines during aging owing to alteration of the hematopoietic niche. However, due to difficult accessibility and other complexities, senescence-related alteration of the hematopoietic niche is largely unknown. The interstitial fluid of bone marrow (IFBM), a pivotal component of the hematopoietic niche, includes soluble secretory factors that are present between bone marrow cells. To characterize the proteomic profile changes of IFBM during aging, we analyzed the IFBMs of young, adult, and senescent rats using 2-DE combined with ESI/MALDI-Q-TOF MS. Finally, 31 differentially expressed proteins involved in multiple biological functions were identified. Peroxiredoxin 2 (Prx2), down-regulated during aging, was further analyzed and demonstrated that it is produced by bone marrow stromal cells. Interestingly, higher levels of hydrogen peroxide (H(2)O(2)) were detected in the bone marrow with lower Prx2 expression. Moreover, exogenous Prx2 reduced the intracellular H(2)O(2) level in bone marrow stromal cells in vitro. Therefore, Prx2 is implied in the regulation of H(2)O(2) production in the bone marrow during aging. Our data characterized the dynamic protein profiles of the bone marrow microenvironment during aging and we provided clues to elucidate the mechanism of creating a low ROS level in the hematopoietic niche.

[Preparation of monoclonal antibody against lung cancer and identification of its targeting antigen].

A mouse-anti-human monoclonal antibody was produced by using the membrane proteins of human lung carcinoma cell line A549 as the immunogen to generate monoclonal antibodies against lung carcinoma with the use of hybridoma techniques. McAb4E7 was prepared successfully. To identify its antigen, proteomic technologies such as two-dimenstional electrophoresis, western blotting and mass spectrometry were employed. The targeting antigen of McAb4E7 expressed positive in human lung cancer cell lines A549 and human hepatocarcinoma cell line HepG2, moreover, the expression of the antigen was stronger in A549 cells. Finally, we obtained one positive protein in A549 cell line that has strong affinity and specificity for McAb4E7, which was identified to be ATP synthase beta subunit. We identified ATP synthase beta subunit as the targeting antigen of lung carcinoma special monoclonal antibody McAb4E7.

Preparative isolation and purification of anti-tumor agent ansamitocin P-3 from fermentation broth of Actinosynnema pretiosum using high-performance counter-current chromatography.

Ansamitocin P-3 is a potent anti-tumor maytansinoid found in Actinosynnema pretiosum. However, due to the complexity of the fermentation broth of Actinomycete, how to effectively separate ansamitocin P-3 is still a challenge. In this study, both analytical and preparative high-performance counter-current chromatography were successfully used to separate and purify ansamitocin P-3 from fermentation broth. A total of 28.8 mg ansamitocin P-3 with purity of 98.4% was separated from 160 mg crude sample of fermentation broth in less than 80 min with the two-phase solvent system of hexane-ethyl acetate-methanol-water (0.6:1:0.6:1, v/v/v/v). The purity and structural identification were determined by HPLC, (1)H NMR, (13)C NMR and mass spectroscopy.

[Experimental study on co-culture of early embryo and cancer cells in vitro].

The co-culture system of early embryos and cancer cells is an important means to observe the biological behavior changes of embryos and cancer cells in vitro. In this study, we co-cultured the 3.5 dpc mouse embryo with malignant tumor cells, investigated the development of blastocyst by observing the hatchment, attachment and outgrowth, observed the biological behavior changes of cancer cells in the embryonic circumstances, and detected the proliferation and apoptosis of cancer cells. Compared with the control, the embryos developed normally in the tumor environments, and the rate of hatchment, attachment and outgrowth increased significantly (P<0.05). However, there was no significant change of cancer cells in morphology, proliferation and apoptosis in the co-culture system (P>0.05). Under the co-culture system, the early embryo developed normally, and the cancer cells also grew well. There may be similarities between the embryos and cancer cell's choice for living. Moreover, the growth of embryos could be promoted by cancer cells in the co-culture system. This might be related to the similarities of gene expression, growth factors and signal transduction mechanisms between embryos and cancer cells.