Overexpression of wild-type HRAS drives non-alcoholic steatohepatitis to hepatocellular carcinoma in mice.

Hepatocellular carcinoma (HCC), a prevalent solid carcinoma of significant concern, is an aggressive and often fatal disease with increasing global incidence rates and poor therapeutic outcomes. The etiology and pathological progression of non-alcoholic steatohepatitis (NASH)-related HCC is multifactorial and multistage. However, no single animal model can accurately mimic the full NASH-related HCC pathological progression, posing considerable challenges to transition and mechanistic studies. Herein, a novel conditional inducible wild-type human HRAS overexpressed mouse model (HRAS-HCC) was established, demonstrating 100% morbidity and mortality within approximately one month under normal dietary and lifestyle conditions. Advanced symptoms of HCC such as ascites, thrombus, internal hemorrhage, jaundice, and lung metastasis were successfully replicated in mice. In-depth pathological features of NASH- related HCC were demonstrated by pathological staining, biochemical analyses, and typical marker gene detections. Combined murine anti-PD-1 and sorafenib treatment effectively prolonged mouse survival, further confirming the accuracy and reliability of the model. Based on protein-protein interaction (PPI) network and RNA sequencing analyses, we speculated that overexpression of HRAS may initiate the THBS1-COL4A3 axis to induce NASH with severe fibrosis, with subsequent progression to HCC. Collectively, our study successfully duplicated natural sequential progression in a single murine model over a very short period, providing an accurate and reliable preclinical tool for therapeutic evaluations targeting the NASH to HCC continuum.

Regulation of T cells by myeloid-derived suppressor cells: emerging immunosuppressor in lung cancer.

Myeloid-derived suppressor cells (MDSCs), major components maintaining the immune suppressive microenvironment in lung cancer, are relevant to the invasion, metastasis, and poor prognosis of lung cancer, through the regulation of epithelial-mesenchymal transition, remodeling of the immune microenvironment, and regulation of angiogenesis. MDSCs regulate T-cell immune functions by maintaining a strong immunosuppressive microenvironment and promoting tumor invasion. This raises the question of whether reversing the immunosuppressive effect of MDSCs on T cells can improve lung cancer treatment. To understand this further, this review explores the interactions and specific mechanisms of different MDSCs subsets, including regulatory T cells, T helper cells, CD8 + T cells, natural killer T cells, and exhausted T cells, as part of the lung cancer immune microenvironment. Second, it focuses on the guiding significance confirmed via clinical liquid biopsy and tissue biopsy that different MDSC subsets improve the prognosis of lung cancer. Finally, we conclude that targeting MDSCs through action targets or signaling pathways can help regulate T-cell immune functions and suppress T-cell exhaustion. In addition, immune checkpoint inhibitors targeting MDSCs may serve as a new approach for enhancing the efficiency of immunotherapy and targeted therapy for lung cancer in the future, providing better comprehensive options for lung cancer treatment.

Efficacy and safety of CalliSpheres drug-eluting beads for bronchial arterial chemoembolization for refractory non-small-cell lung cancer and its impact on quality of life: A multicenter prospective study.

Objective: This study aimed to prospectively observe the efficacy and safety of CalliSpheres drug-eluting beads bronchial arterial chemoembolization (DEB-BACE) for refractory non-small-cell lung cancer (NSCLC). Methods: The interventional therapy plan was as follows: 300-500 µm CalliSpheres drug-loaded microspheres were loaded with epirubicin, and then slow embolization of tumor supplying artery was performed after microcatheter superselection. Chest enhanced computed tomography and related hematological examination were reviewed after 2 months of DEB-BACE, and the tumor response after the first interventional therapy was evaluated using modified response evaluation criteria in solid tumors. The overall survival (OS) of patients was determined, and the quality of life and the incidence rate of adverse reactions were observed. Results: From January 2019 to January 2021, 43 patients with refractory NSCLC were enrolled. The patients were followed up until June 2022. All 43 patients underwent DEB-BACE 1.79 ± 0.69 times on average. The 3-, 6-, 12-, and 24-month survival rates were 100%, 86.0%, 41.9%, and 11.8%, respectively. The median OS was 11.5 months. After the first interventional treatment, cough and wheezing significantly improved in 31 patients, hemoptysis was effectively controlled in 12 patients, and superior vena cava compression disappeared in 2 patients after 2 times of treatment. The general health status of the patients after treatment significantly improved compared with that before treatment, including the improvement in physical and emotional functions. Fatigue, nausea and vomiting, dyspnea, and insomnia improved significantly after treatment. No serious adverse events, such as spinal cord injury and cerebral embolism, were observed during the perioperative period. The main adverse reaction after DEB-BACE was chest pain (13/43, grade 1) followed by fever (10/43, grade 1-2), which was significantly relieved within 3-5 days after symptomatic treatment. Other adverse reactions included irritating cough, nausea and vomiting, and bone marrow suppression, and the incidence was less than 20%. Conclusions: DEB-BACE was effective and safe in treating refractory NSCLC, which could significantly improve patients' quality of life and was worthy of clinical promotion and application.

Retrospective Clinical Study on Integrated Chinese and Western Medicine in Treatment of Limited-Stage Small Cell Lung Cancer.

OBJECTIVE: To investigate the efficacy of integrated Chinese and Western medicine extending the progression-free survival (PFS) and overall survival (OS) of limited-stage small cell lung cancer (LS-SCLC) patients after the first-line chemoradiotherapy. METHODS: The data of 67 LS-SCLC patients who received combined treatment of CM and Western medicine (WM) between January 2013 and May 2020 at the outpatient clinic of Guang'anmen Hospital were retrospectively analyzed. Thirty-six LS-SCLC patients who received only WM treatment was used as the WM control group. The medical data of the two groups were statistically analyzed. Survival analysis was performed using the product-limit method (Kaplan-Meier analysis). The median OS and PFS were calculated, and survival curves were compared by the Log rank test. The cumulative survival rates at 1, 2, and 5 years were estimated by the life table analysis. Stratified survival analysis was performed between patients with different CM administration time. RESULTS: The median PFS in the CM and WM combination treatment group and the WM group were 19 months (95% CI: 12.357-25.643) vs. 9 months (95% CI: 5.957-12.043), HR=0.43 (95% CI: 0.27-0.69, P<0.001), respectively. The median OS in the CM and WM combination group and the WM group were 34 months (95% CI could not be calculated) vs. 18.63 months (95% CI: 16.425-20.835), HR=0.40 (95% CI: 0.24-0.66, P<0.001), respectively. Similar results were obtained in the further stratified analysis of whether the duration of CM administration exceeded 18 and 24 months (P<0.001). CONCLUSION: The combination treatment of CM and WM with continuing oral administration of CM treatment after the first-line chemoradiotherapy for LS-SCLC patients produced better prognosis, lower risks of progression, and longer survival than the WM treatment alone. (Registration No. ChiCTR2200056616).

Mechanism of 'Invigorating Qi and Promoting Blood Circulation' Drug Pair Ginseng-Danshen on Treatment of Ischemic Heart Disease Based on Network Pharmacology.

OBJECTIVE: Using network pharmacology to explore the mechanism of the 'invigorating qi and promoting blood circulation' drug pair Ginseng-Danshen (Salvia miltiorrhiza) on treatment of ischemic heart disease (IHD). METHODS: The chemical constituents of ginseng and Danshen drug pair were identified by searching the Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform (TCMSP), and the potential targets of the pair were identified. The pharmacodynamics of the pair was analyzed using network pharmacology. The targets of IHD were identified by database screening. Using protein-protein interaction network, the interaction targets of Ginseng-Danshen on IHD were constructed. A "constituent-target-disease" interaction network was constructed using Cytoscape software, Gene Ontology (GO) term enrichment analysis and biological pathway enrichment analysis were carried out, and the mechanism of improving myocardial ischemia by the Ginseng-Danshen drug pair was investigated. RESULTS: Seventeen active constituents and 53 targets were identified from ginseng, 53 active constituents and 61 targets were identified from Danshen, and 32 protein targets were shared by ginseng and Danshen. Twenty GO terms were analyzed, including cytokine receptor binding, cytokine activity, heme binding, and antioxidant activity. Sixty Kyoto Encyclopedia of Genes and Genomes (KEGG) signaling pathways were analyzed, including phosphatidylinositol 3-kinase-serine-threonine kinase (PI3K-AKT) signaling pathway, p53 signaling pathway, interleukin 17 signaling pathway, tumor necrosis factor signaling pathway, and the advanced glycation end product (AGE)-the receptor for AGE (RAGE) signaling pathway in diabetic complications. CONCLUSION: The specific mechanism of Ginseng-Danshen drug pair in treating IHD may be associated with improving the changes of metabolites inbody, inhibiting the production of peroxides, removing the endogenous oxygen free radicals, regulating the expression of inflammatory factors, reducing myocardial cell apoptosis and promoting vascular regeneration.

[Salvianolic acid B regulates mitochondrial autophagy mediated by NIX to protect H9c2 cardiomyocytes from hypoxia/reoxygenation injury].

The aim of this paper was to investigate whether the mechanism of salvianolic acid B in protecting H9 c2 cardiomyocytes from hypoxia/reoxygenation injury is related to the regulation of mitochondrial autophagy mediated by NIX. H9 c2 cardiomyocytes were cultured in vitro and divided into normal group, model group and salvianolic acid B group(50 µmol·L~(-1)). Hypoxia/reoxygenation injury model was established by hypoxia for 4 h and reoxygenation for 2 h. In normal group, high glucose DMEM medium was used for culture. Those in model group were cultured with DMEM medium without glucose and oxygen, and no drugs for hypoxia and reoxyge-nation. In salvianolic acid B group, salvianolic acid B prepared by glucose-free DMEM medium was added during hypoxia, and the other process was as same as the model group. The cell viability was evaluated by CCK-8 assay. The leakage of lactate dehydrogenase(LDH) was detected by microplate method. The levels of intracellular reactive oxygen species(ROS) and mitochondrial membrane potential(ΔΨm) were measured by chemical fluorescence method. The level of intracellular adenosine triphosphate(ATP) was mea-sured by fluorescein enzyme method. The autophagy related proteins LC3-Ⅰ, LC3-Ⅱ, apoptosis related protein cleaved caspase-3 and mitochondrial autophagy receptor protein NIX were detected by Western blot. As compared with the normal group, the activity of H9 c2 cardiomyocytes and ATP level were decreased(P<0.05); LDH leakage and ROS production were increased(P<0.01); ΔΨm was decreased(P<0.01); LC3-Ⅱ/LC3-Ⅰ ratio, cleaved caspase-3 and NIX protein expression levels were increased(all P<0.05) in the model group. As compared with the model group, the activity of cells and ΔΨm were significantly increased(P<0.01); ATP level was increased(P<0.05); LDH leakage and ROS generation were decreased(P<0.01); LC3-Ⅱ/LC3-Ⅰ ratio was decreased(P<0.01); cleaved caspase-3 and NIX expression levels were decreased(P<0.05) in the salvianolic acid B group. The protective effect of salvianolic acid B on hypoxia/reoxygenation injury of H9 c2 cardiomyocytes may be associated with inhibiting mitochondrial auto-phagy. The specific mechanism may be related to inhibiting the activation of mitochondrial autophagy mediated by NIX, increasing ΔΨm, reducing ROS production, reducing the expression of cleaved caspase-3, LC3-Ⅱ, and increasing cell viability.

[Protective effect of safflower yellow injection against rat MIRI by TLR-NF-κB inflammatory pathway].

This study was to investigate the mechanism of safflower yellow injection for regulating inflammatory response against myocardial ischemia-reperfusion injury( MIRI) in rats. Male Wistar rats were randomly divided into sham operation group,model group,Hebeishuang group,safflower yellow injection high,medium and low dose groups. MIRI model was established by ligating left anterior descending coronary artery. Myocardial histopathological changes were observed by HE staining; myocardial infarct size was detected by TTC staining; content and changes of tumor necrosis factor-α( TNF-α) and interleukin-6( IL-6),serum creatine kinase( CK),aspartate aminotransferase( AST),and lactate dehydrogenase( LDH) were detected by biochemical method or enzyme-linked immunosorbent assay( ELISA). Western blot assay was used to detect the protein expression of Toll-like receptor 4( TLR4) and nuclear factor-κB( NF-κB p65) in myocardial tissues. The results showed that as compared with the sham operation group,the myocardial arrangement of the model group was disordered,with severe edemain the interstitial,significantly increased area of myocardial infarction,increased activities of AST,CK and LDH in serum,and significantly increased contents of TNF-α and IL-6; the expression levels of TLR4 and NF-κB( p65) protein in myocardial tissues were also increased. As compared with the model group,the myocardial tissues were arranged neatlyin the Hebeishuang group and safflower yellow injection high,medium and low dose groups; the edema was significantly reduced; the myocardial infarct size was significantly reduced; the serum AST,CK,LDH activity and TNF-α,IL-6 levels were significantly decreased,and the expression levels of TLR4 and NF-κB( p65) protein in myocardial tissues were decreased. As compared with the Hebeishuang group,the myocardial infarct size was larger in the safflower yellow injection high,medium and low dose groups; the activities of AST,CK and LDH in serum and the contents of TNF-α and IL-6 in serum were higher,but there was no statistically significant difference in the expression levels of TLR4 and NF-κB( p65) protein in tissues. It is suggested that safflower yellow injection has a significant anti-MIRI effect,and its mechanism may be related to the regulation of TLR-NF-κB pathway to inhibit inflammatory response.

[A multicenter epidemiological investigation of brain injury in hospitalized preterm infants in Anhui, China].

OBJECTIVE: To investigate the risk factors for brain injury in preterm infants by a multicenter epidemiological investigation of brain injury in hospitalized preterm infants in Anhui, China. METHODS: Preterm infants who were hospitalized in the department of neonatology in 9 hospitals of Anhui Neonatal Collaboration Network between January 2016 and January 2017 were enrolled as subjects. The data of maternal pregnancy and clinical data of preterm infants were collected, and the logistic regression model was used to analyze the risk factors for brain injury in preterm infants. RESULTS: A total of 3 378 preterm infants were enrolled. Of the 3 378 preterm infants, 798 (23.56%) had periventricular-intraventricular hemorrhage (PVH-IVH), and 88 (2.60%) had periventricular leukomalacia (PVL). Intrauterine distress, anemia, hypoglycemia and necrotizing enterocolitis (NEC) were risk factors for PVH-IVH (OR=1.310, 1.591, 1.835, and 3.310 respectively; P<0.05), while a higher gestational age was a protective factor against PVH-IVH (OR=0.671, P<0.05). PVH-IVH, NEC and mechanical ventilation were risk factors for PVL (OR=4.017, 3.018, and 2.166 respectively; P<0.05), and female sex and use of pulmonary surfactant were protective factors against PVL (OR=0.514 and 0.418 respectively; P<0.05). CONCLUSIONS: Asphyxia/anoxia, infection/inflammation, mechanical ventilation, anemia and hypoglycemia may increase the risk of brain injury in preterm infants.

Synthesis and antitumor activity evaluation of novel oleanolic acid derivatives.

Ten novel oleanolic acid (OA) derivatives were synthesized through modifications at positions of A ring and C-28. Inhibitory activities of the oleanolic acid derivatives against SGC7901 and A549 cell lines were evaluated and confirmed by the tetrazolium bromidesalt (MTT) assay. The lab results revealed that all these compounds displayed some antitumor activity against SGC-7901 and A-549 cell lines. Among them, II4 and II5 exhibited excellent antitumor activities against SGC7901 cells and A549 cells, compared with gefitinib. Molecular docking studies have shown that compounds II4 and II5 produce potent antitumor activities by interacting with C-kit receptor through hydrogen bonds and hydrophobic bonds.

Design, synthesis and evaluation of antitumor activity of new rotundic acid acylhydrazone derivatives.

In light of the important antitumor activity of acylhydrazone compounds and based on our previous study, 18 new rotundic acid (RA) acylhydrazone derivatives were synthesized. All of the compounds were characterized by their spectroscopic data. The antiproliferative activity of the compounds was evaluated in vitro via the MTT method in three tumor cell lines, including A-375 (human malignant melanoma cells), SPC-A1 (human lung adenocarcinoma) and NCI-H446 (small cell lung cancer). The results showed that the antiproliferative activity of all of the compounds on the NCI-H446 cell line did not increase compared to RA, however, most of the derivatives exhibited higher activity against the A375 and SPC-A1 cell lines as compared to RA. Importantly, the antiproliferative activities of compounds 5a and 5b were the highest among the compounds, with IC(50) values <10 µM. Collectively, compounds 5a and 5b may act as potential anti-tumor agents in the future.

Matrix metalloproteinase-9 as a prognostic factor in gastric cancer: a meta-analysis.

BACKGROUND: Matrix metalloproteinase-9 (MMP-9) is associated with disruption of basement membranes of blood vessels and promotion of metastasis through the lymphatics. However, its prognostic value for survival in patients with gastric cancer remains controversial. METHOD: We therefore conducted a meta-analysis of the published literature in order to clarify the impact of MMP-9. Clinical studies were selected for further analysis if they provided an independent assessment of MMP-9 in gastric cancer and reported analysis of survival data according to MMP-9 expression. RESULTS: A total of 11 studies, covering 1700 patients, were included for meta- analysis. A summary hazard ratio (HR) of all studies and sub-group hazard ratios were calculated. The combined HR suggested that a positive MMP-9 expression had an impact on overall survival: 1.25 (95% confidence interval 1.11-1.40) in all eligible studies; 1.13 (1.06-1.20) in 8 studies detecting MMP-9 by immunohistochemistry; 1.36 (1.12-1.65) in 7 studies from Asia. Only one study for DFS showed a significant impact on disease free survival (HR 1.73, 95%CI 1.27-2.34). CONCLUSIONS: Our findings suggested that MMP-9 protein expression might be a factor for a poor prognosis in patients with gastric cancer. However, the association was rather weak, so that more prospective studies should further explore the prognostic impact of MMP-9 mRNA and correlations between MMP-9 and clinicopathological characteristics.

Prognostic significance of tumor-associated macrophages in solid tumor: a meta-analysis of the literature.

PURPOSE: Tumor associated macrophages (TAMs) are considered with the capacity to have both negative and positive effects on tumor growth. The prognostic value of TAM for survival in patients with solid tumor remains controversial. EXPERIMENTAL DESIGN: We conducted a meta-analysis of 55 studies (n = 8,692 patients) that evaluated the correlation between TAM (detected by immunohistochemistry) and clinical staging, overall survival (OS) and disease free survival (DFS). The impact of M1 and M2 type TAM (n = 5) on survival was also examined. RESULTS: High density of TAM was significantly associated with late clinical staging in patients with breast cancer [risk ratio (RR)  = 1.20 (95% confidence interval (CI), 1.14-1.28)] and bladder cancer [RR = 3.30 (95%CI, 1.56-6.96)] and with early clinical staging in patients with ovarian cancer [RR = 0.52 (95%CI, 0.35-0.77)]. Negative effects of TAM on OS was shown in patients with gastric cancer [RR = 1.64 (95%CI, 1.24-2.16)], breast cancer [RR = 8.62 (95%CI, 3.10-23.95)], bladder cancer [RR = 5.00 (95%CI, 1.98-12.63)], ovarian cancer [RR = 2.55 (95%CI, 1.60-4.06)], oral cancer [RR = 2.03 (95%CI, 1.47-2.80)] and thyroid cancer [RR = 2.72 (95%CI, 1.26-5.86)],and positive effects was displayed in patients with colorectal cancer [RR = 0.64 (95%CI, 0.43-0.96)]. No significant effect was showed between TAM and DFS. There was also no significant effect of two phenotypes of TAM on survival. CONCLUSIONS: Although some modest bias cannot be excluded, high density of TAM seems to be associated with worse OS in patients with gastric cancer, urogenital cancer and head and neck cancer, with better OS in patients with colorectal cancer.

Comparative proteomic approach identifies PKM2 and cofilin-1 as potential diagnostic, prognostic and therapeutic targets for pulmonary adenocarcinoma.

Lung cancer is the leading cause of cancer-related death in the world. Non-small cell lung carcinomas (Non-SCLC) account for almost 80% of lung cancers, of which 40% were adenocarcinomas. For a better understanding of the molecular mechanisms behind the development and progression of lung cancer, particularly lung adenocarcinoma, we have used proteomics technology to search for candidate prognostic and therapeutic targets in pulmonary adenocarcinoma. The protein profile changes between human pulmonary adenocarcinoma tissue and paired surrounding normal tissue were analyzed using two-dimensional polyacrylamide gel electrophoresis (2-DE) based approach. Differentially expressed protein-spots were identified with ESI-Q-TOF MS/MS instruments. As a result, thirty two differentially expressed proteins (over 2-fold, p<0.05) were identified in pulmonary adenocarcinoma compared to normal tissues. Among them, two proteins (PKM2 and cofilin-1), significantly up-regulated in adenocarcinoma, were selected for detailed analysis. Immunohistochemical examination indicated that enhanced expression of PKM2 and cofilin-1 were correlated with the severity of epithelial dysplasia, as well as a relatively poor prognosis. Knockdown of PKM2 expression by RNA interference led to a significant suppression of cell growth and induction of apoptosis in pulmonary adenocarcinoma SPC-A1 cells in vitro, and tumor growth inhibition in vivo xenograft model (P<0.05). In addition, the shRNA expressing plasmid targeting cofilin-1 significantly inhibited tumor metastases and prolonged survival in LL/2 metastatic model. While additional works are needed to elucidate the biological significance and molecular mechanisms of these altered proteins identified in this study, PKM2 and cofilin-1 may serve as potential diagnostic and prognostic biomarkers, as well as therapeutic targets for pulmonary adenocarcinoma.

[The molecular mechanism of extravasation in mouse melanoma lung metastasis model].

OBJECTIVE: To study molecular mechanisms underlying the extravasation of mice melanoma cells during lung metastasis. METHODS: B16-RED melanoma cell line was established which stably express the red fluorescent protein. B16-RED cells were compared with B16 cells in ability of proliferation and lung metastasis. A mouse lung metastasis model was established with B16-RED melanoma cells. FITC-dextran was injected i.v. and CD31 indirect immunoflourescence (IIF) staining was made to identify the location of the tumor cells and the time of tumor cell extravasation. Finally, at 48 hours post cell injection, the lung and a normal lung were removed and used for 32K mice microarray analysis. RESULTS: B16-RED was consistent with B16 in cell shape and ability of proliferation and lung metastasis. 52.7% of B16-RED melanoma cells completed the extravasation within 48 hours in mouse lung metastasis model. Many important signal pathways were involved during lung metastasis, including leukocyte transendothelial migration, MAPK signaling pathway, neuroactive ligand-receptor interaction, focal adhesion, cytokine-cytokine receptor interaction, regulation of actin cytoskeleton, axon guidance, calcium signaling pathway, tight junction, etc. CONCLUSION: The extravasation during metastasis is a complex and multiple-steps process, in which many important signal pathways in host tissues were involved.

[Antitumor effect by combination of shRNA interfering plasmid targeting PKM2 with recombinant endostatin].

OBJECTIVE: To investigate the enhancement effect of the combination of shRNA interfering plasmid targeting PKM2 with recombinant Endostatin in the treatment of lung cancer. METHODS: Twenty five BABL/nu/nu mice bearing A549 lung cancer were divided into 5 groups (NS control, psh-Control, psh-PKM2 treated group, Endostar treated group, psh-PKM2+Endostar treated group) and treated with shRNA interfering plasmid targeting PKM2 and recombinant Endostatin respectively or in combination. The expression of PKM2 in A549 detected with immunofluorescent assay. The interference effect of psh-PKM2 was determined by Western blot. The tumor volume, microvessel density (MVD), apoptosis index (AI) and side effects were observed. RESULTS: The combination treatment of RNA interfering plasmid targeting PKM2 with recombinant Endostatin inhibited tumor growth obviously (P < 0.05); The combination group revealed a decreased MVD and an increased AI (P < 0.05). CONCLUSION: The combination of shRNA interfering plasmid targeting PKM2 with recombinant Endostatin might enhance anti-tumor effect by increasing the apoptosis of the cancer cell.

Hyperthermia increases the therapeutic efficacy of survivinT34A in mouse tumor models.

The use of survivinT34A mutant targeted disruption of survivin, the strongest inhibitor of apoptosis protein overexpressed in tumors, has proved a promising strategy for advanced cancers. However, hyperthermia, as a cytotoxic enhancer, regularly activates the expression of survivin to counteract the heat-induced antitumor activity. Here, we investigated the combinational antitumor effect by using liposome-encapsulated mouse survivinT34A and hyperthermia in mouse models. We observed that the combination treatment of surivinT34A and hyperthermia significantly increased the growth inhibition and apoptosis of tumor cells in vitro compared with single treatment or other controls, which was similar to the effect of survivin silencing in combination with hyperthermia. Moreover, the inhibition of tumor growth in vivo was also remarkably enhanced by combination of surivinT34A and hyperthermia when compared with other treatments. Naturally, the tumor tissues in combination treatment presented the larger necrosis-like areas, more apoptotic cells and less microvessel density. Our findings suggest that the antitumor efficacy of survivin disruption can be enhanced by hyperthermia, which might be a new feasible approach for cancer therapy.

Enhanced antitumor efficacy by blocking activation of the phosphatidylinositol 3-kinase/Akt pathway during anti-angiogenesis therapy.

Anti-angiogenesis has been a promising strategy for cancer therapy. However, many signal pathways are activated during anti-angiogenic treatment to counteract the therapeutic efficacy. Among these pathways, evidence has directly pointed to the phosphatidylinositol 3-kinase/Akt (PI3K/Akt) pathway, whose activation resulted in tolerance to the absence of nutrients and oxygen when tumor angiogenesis has been inhibited. In the present study, we investigated the effects of blocking activation of the PI3K/Akt pathway on cell survival in vitro and tumor growth in vivo during anti-angiogenesis therapy. In modeled microenvironments in vitro, we observed that the phosphorylation of Akt in tumor cells was increased gradually in the absence of serum and oxygen in a time-dependent manner. The specific inhibitors of PI3K inhibited the proliferation of tumor cells in a dose-dependent manner in vitro. Moreover, inhibition was enhanced gradually with increased serum deprivation and/or hypoxia. In a mouse tumor model, we found the phosphorylation of Akt obviously increased following anti-angiogenic therapy using plasmids encoding soluble vascular endothelial growth factor receptor-2, but significantly reduced after treatment with LY294002. Consequently, the combinational treatment exhibited better antitumor effects compared with single treatments, presenting larger necrosis-like areas, more apoptotic cells, less microvessel density and less phosphorylated Akt in tumors. These results suggest that blocking activation of the PI3K/Akt pathway during anti-angiogenesis therapy could enhance antitumor efficacy. Thus, targeting the PI3K/Akt pathway might be a promising strategy to reverse tumor resistance to anti-angiogenesis therapy.

[Anti-tumor effects induced by the DNA vaccine coding human and mouse soluble VEGFR2].

OBJECTIVE: To develop a novel anti-angiogenesis strategy based on a DNA vaccine coding both human and mouse soluble VEGFR2. METHODS: The gene fragments coding human and mouse sVEGFR2 were amplified with PCR and cloned into pVITRO2 to generate pVITRO2-hm-sVEGFR2 recombinant. The in vitro VEGF blocking effect of the pVITRO2-hm-sVEGFR2 expression products on HUVEC cells were evaluated. The anti-tumor effect of pVITRO2-hm-sVEGFR2 was studied in mouse B16 model. The microvessels were stained by using CD31 antibody. RESULTS: The co-expressing vector pVITRO2-hm-sVEGFR2 was constructed successfully, confirmed by the restriction endonuclease digestion and sequencing. The expressing products of pVITRO2-hm-sVEGFR2 could obviously block the function of VEGF on promoting the proliferation of HUVEC in vitro. The tumor growth in mice was also significantly inhibited by pVITRO2-hm-sVEGFR2 expression. CD31 staining demonstrated that the microvessel density obviously decreased in tumor tissues treated with pVITRO2-hm-sVEGFR2. Both anti-tumor and anti-angiogenesis effects of pVITRO2-hm-sVEGFR2 were stronger than that of plasmids which coding only human or mouse sVEGFR2. CONCLUSION: pVITRO2-hm-sVEGFR2 could be a novel DNA vaccine for the anti-tumor therapy by inhibiting angiogenesis.

[IL-15 enhance the therapeutic effects of whole cell vaccine in mouse CT26 colon carcinoma model].

OBJECTIVE: To determine the enhancement effects of IL-15 to the tumor whole cell vaccine in tumor immunotherapy. METHODS: CT26 colon carcinoma model was established with BALB/c mice. Thirty two mice with CT26 colon carcinoma were divided randomly into four groups, which were subcutaneously injected at several spots with PBS (200 microL), CT26 whole cell vaccine (2 x 10(6) cells in 200 microL PBS), mIL-15 (20 microg, encapsulated with liposome in 200 microL 5% glucose solution) and CT26 whole cell vaccine (2 x 10(6) cells in 100 microL PBS) plus mIL-15 (20 microg, encapsulated with liposome in 100 microL 5% glucose solution) respectively every three days for six doses, the plasmid was injected beside the vaccine injecting spots. The size of tumors was measured every four days. All mice were sacrificed 30 days after tumor implantation. The pathologic observation and apoptotic analysis of tumors were preceded. RESULTS: CT26 whole cell vaccine combined with mIL-15 inhibited tumor growth by 45% compared with that of control group, the differences between CT26 + mIL-15 group and the other three groups were significant (P < 0. 05). The HE staining showed that the necrosis areas in tumors of the CT26 + mIL-15 group were larger than those of other three groups. The apoptotic index of tumors from the CT26 + mIL-15 group was (46.7 +/- 7.2)%, higher than that of the other three groups obviously (P < 0.05). CONCLUSION: IL-15 could enhance the therapeutic effects of CT26 whole cell vaccine in tumor immunotherapy.

Physiological and biochemical characteristics and molecular-biological identification of a gigantic tobacco mutant.

A new gigantic late-flowering tobacco mutant was isolated in tobacco field in Xunyang county, Shaanxi province, in 2001. It was rescued through tissue culture and a large amount of regenerated plantlets were obtained. The results of the comparison between the regenerated plants from this mutant and the wild type plant (K346) were as follows: (1) Morphological observation showed that the leaf number of the mutant was 3.3 times as many as that of the wild type, the height of mutant was 2.2 folds that of the wild type, and the mutant had the late-flowering character. (2) Cytological examination showed that the mutant was a normal diploid, and the number of chloroplasts in a guard cell of mutant was 1.3 times that of the wild type. (3) Both chlorophyll a and b content of the mutant were larger than that of the wild type; soluble protein content of the mutant was 1.18 times as much as that of the wild type. Peroxidase isozyme and cytochrome-oxidase isozyme electrophoresis analyses indicated differences between the mutant and the wild type. The soluble protein SDS-PAGE patterns showed the absence of four bands [P1 (114.6 kD), P2 (103 kD), P3 (66.2 kD), P4 (24 kD)] in the mutant. (4) RAPD analysis showed that the similarity index of the mutant and the wild type was 0.612. This suggested that there were changes at DNA level. The mRNA of mutant leaves at flowering stage was isolated; DDRT-PCR was carried out using 10 random primers, using OligodT(15)M (M=A/G/C) as anchor primer. It has been proved that gene expression at anthesis was different between the mutant and the wild type. (5) Genetic observation showed that the mutant was homozygotic and bred true. And the mutant was a late-flowering one.