Pre-clinical Efficacy and Safety Pharmacology of PEGylated Recombinant Human Endostatin

INTRODUCTION

This study aimed to outline the pre-clinical efficacy and safety pharmacology of PEGylated recombinant human endostatin (M2ES) according to the requirements of new drug application.

METHODS

The purity of M2ES was evaluated by using silver staining. Transwell migration assay was applied to detect the bioactivity of M2ES in vitro. The antitumor efficacy of M2ES was evaluated in an athymic nude mouse xenograft model of pancreatic cancer (Panc-1) and gastric cancer (MNK45). BALB/C mice were treated with different doses of M2ES (6, 12 and 24 mg/kg) intravenously, both autonomic activity and cooperative sleep were monitored before and after drug administration.

RESULTS

The apparent molecular weight of M2ES was about 50 kDa, and the purity was greater than 98%. Compared with the control group, M2ES significantly inhibits human micro-vascular endothelial cells (HMECs) migration in vitro. Notably, weekly administration of M2ES showed a significant antitumor efficacy when compared with the control group. Treatment of M2ES (24mg/kg or below) showed no obvious effect on both autonomic activity and hypnosis.

CONCLUSION

On the basis of the pre-clinical efficacy and safety pharmacology data of M2ES, M2ES can be authorized to carry out further clinical studies.

Efficacy and safety of immune checkpoint inhibitors plus recombinant human endostatin therapy as second-line treatment in advanced non-small-cell lung cancer with negative driver gene: a pilot study

Background

Immune checkpoint inhibitors (ICIs) have become the standard second-line treatment for advanced non-small cell lung cancer (NSCLC). Recent findings indicating an intertwined regulation of vascular endothelial growth factor (VEGF) signaling and immunosuppression in the tumor microenvironment suggest that the combination of ICIs and angiogenesis inhibitors could have synergistic antitumor activity, along with favorable tolerability. However, ICIs plus anti-angiogenesis therapy has not been widely evaluated. The purpose of this pilot study was to evaluate the efficacy and safety of ICIs plus recombinant human (rh)-endostatin as second-line treatment in advanced NSCLC with negative driver gene.

Method

Prospectively evaluated the efficacy and safety of ICIs plus rh-endostain as second-line treatment in advanced NSCLC with negative driver gene. The primary endpoints of the study were progression-free survival (PFS) and overall survival (OS). The secondary endpoints were objective response rate (ORR), disease control rate (ORR), and safety.

Results

A total of 34 patients were recruited in this study. 18 patients received ICIs plus anti-angiogenesis therapy (ICIs combination therapy), and 16 patients received ICIs monotherapy. DCR was 88.9% vs 43.8% (P = 0.009). Median PFS (mPFS) was 8.3 months vs. 3.7 months (HR = 0.276, 95% CI 0.125-0.607, P = 0.001). Median OS (mOS) was 18.0 months vs 9.6 months (HR=0.364, 95% CI 0.147-0.902, P=0.009). In multivariate Cox regression analysis, ICI combination therapy prolonged PFS (HR = 0.069, 95% CI 0.019-0.185, P < 0.001) and OS (HR = 0.044, 95% CI 0.011-0.185, P < 0.001). We did not observe a significant difference in the incidence of adverse events (AEs) between the two groups (P > 0.05).

Conclusions

Compared with ICIs monotherapy, ICIs combination therapy improves clinical response in patients with advanced NSCLC with negative driver gene, significantly prolongs PFS and OS, and does not significantly difference the incidence of AEs.

Performance of Pretreatment MRI-Based Radiomics in Recombinant Human Endostatin Plus Concurrent Chemoradiotherapy Response Prediction in Nasopharyngeal Carcinoma: A Retrospective Study

PURPOSE

To investigate the capability of an Magnetic resonance imaging (MRI) radiomics model based on pretreatment texture features in predicting the short-term efficacy of recombinant human endostatin (RHES) plus concurrent chemoradiotherapy (CCRT) for nasopharyngeal carcinoma (NPC).

METHODS

We retrospectively enrolled 65 patients newly diagnosed as having NPC and treated with RHES + CCRT. A total of 144 texture features were extracted from the MRI before RHES + CCRT treatment of all the NPC patients. The maximum relevance minimum redundancy (mRMR) method was used to remove redundant, irrelevant texture features, and calculate the Rad score of the primary tumor. Multivariable logistic regression was used to select the most predictive features subset, and prediction models were constructed. The performance of the 3 models in predicting the early response of RHES + CCRT for NPC was explored.

RESULTS

The diagnostic efficiency of combined model and radiomics model in distinguishing between the effective and the ineffective groups of patients was found to be moderate. The area under the ROC curve (AUC) of the combined model and radiomics model was 0.74 (95% confidence interval [CI]: 0.62-0.86) and 0.71 (95% CI: 0.58-0.84), respectively, with both being higher than the AUC of the clinics model (0.63, 95% CI: 0.49-0.78). Compared with the radiomics model, the combined model showed marginally improved diagnostic performance in predicting RHES + CCRT treatment response. The accuracy of combined model and radiomics model for RHES + CCRT response assessment in NPC were higher than those of the clinics model (0.723, 0.723 vs 0.677).

CONCLUSION

The pretreatment MRI-based radiomics may be a noninvasive and effective method for the prediction of RHES + CCRT early response in patients with NPC.

Endostatin induces normalization of blood vessels in colorectal cancer and promotes infiltration of CD8+ T cells to improve anti-PD-L1 immunotherapy

INTRODUCTION

The purpose of this study was to evaluate recombinant human endostatin (rHE)-induced normalization of the tumor vasculature in colorectal cancer (CRC) and to evaluate the therapeutic effects of combined treatment with rHE and a programmed death ligand-1 (PD-L1) inhibitor.

METHODS

A mouse subcutaneous tumorigenesis model was established to evaluate the antitumor effects of endostatin combined with a PD-L1 inhibitor on CRC. Intravoxel incoherent motion diffusion-weighted magnetic resonance imaging (IVIM-DW MRI) was used to evaluate changes in the intratumor microcirculation in response to combined treatment with endostatin and a PD-L1 inhibitor. The infiltration density and function of CD8+ T cells in tumors were evaluated using flow cytometry. Finally, clinical specimens were used to evaluate the expression area of tumor vascular pericytes and CD8+ T cells in tumor tissues.

RESULTS

The antitumor effects of endostatin combined with a PD-L1 inhibitor were significantly greater than those of endostatin or a PD-L1 inhibitor alone. On the ninth day of intervention, the endostatin group showed significantly higher pseudo diffusion parameter (D*) and microvascular volume fraction (F) values in tumors than those in the control group or PD-L1 group. After 27 days of intervention, the endostatin groups showed significantly lower levels of vascular endothelial growth factor (VEGF) and transforming growth factor (TGF)-β than those in the control group. Treatment of CD8+ T cells with endostatin for 24 h did not alter the expression levels of markers of reduced T-cell activity. However, endostatin reversed the VEGF-mediated inhibition of the secretion of interferon (IFN)-γ from T cells. The results in CRC clinical samples showed that treatment with endostatin induced significantly higher infiltration of CD8+ T cells compared with treatment that did not include endostatin. Furthermore, the expression area of pericytes was significantly positively related to the infiltration density of CD8+ T cells and overall survival time.

CONCLUSION

Endostatin improved the antitumor effects of PD-L1 inhibitors on CRC, significantly increased the activity of CD8+ T cells, and synergistically improved the tumor treatment effect of the two inhibitors.

Endostar Synergizes with Radiotherapy to Inhibit Angiogenesis of Cervical Cancer in a Subcutaneous Xenograft Mouse Model

BACKGROUND

To investigate the synergic effect and underlying mechanism of Endostar, a recombinant human endostatin used for anti-angiogenesis, in radiotherapy for cervical cancer.

METHODS

The Cell Counting Kit-8 (CCK-8) assay and plate cloning experiment were first employed to analyze the proliferation of HeLa and SiHa cervical cancer cells and human umbilical vein vascular endothelial cells (HUVECs). Flow cytometry was used to detect apoptosis and cell cycle progression. A tube formation assay was used to assess angiogenesis in vitro. The expression of gamma H2A histone family member X (γ-H2AX) and activation of the vascular endothelial growth factor receptor (VEGFR) signaling pathway were detected by immunofluorescence and western blotting, respectively. In a HeLa xenograft model, tumor tissue expression of CD31 and alpha smooth muscle actin and serum expression of VEGF-A were detected by immunohistochemistry (IHC) and enzyme-linked immunosorbent assay, respectively.

RESULTS

The CCK-8 and plate cloning assays showed that Endostar and radiotherapy synergistically inhibited the growth of HUVECs but not HeLa and SiHa cells. The flow cytometric results showed that Endostar only promoted radiotherapy-induced apoptosis and G2/M phase arrest in HUVECs (p < 0.05). Endostar combined with radiotherapy also significantly inhibited tube formation by HUVECs (p < 0.05). Furthermore, Endostar inhibited the radiotherapy-induced expression of γH2AX (p < 0.05) and phosphorylation of VEGFR2/PI3K/AKT/DNA-PK in HUVECs (p < 0.05). IHC showed that Endostar enhanced the inhibitory effect of radiotherapy on the microvessel density in xenograft tumor tissues (p < 0.05), as well as serum VEGF-A expression (p < 0.05). The tumor volume in the combination therapy groups (1200 mm3) was significantly lower than in the control group (2500 mm3; p < 0.05).

CONCLUSIONS

Our findings provide experimental evidence and a theoretical basis for the application of Endostar in combination with irradiation for anti-cervical cancer treatment.

Construction and Evaluation of Traceable rhES-QDs-M-MS Protein Delivery System: Sustained-Release Properties, Targeted Effect, and Antitumor Activity

Recombinant human endostatin (rhES) is a protein drug with poor stability and short in vivo circulation time. The present study was therefore aimed at developing sustained-release lung targeted microspheres drug delivery system and evaluating its targeting efficiency using in vivo imaging techniques with quantum dots (QDs) as the imaging material. The oil-soluble QDs were coated with amphiphilic polymers to obtain a polymer-quantum dots micelle (QDs-M) with the potential to stably disperse in water. The rhES and QDs-M were combined using covalent bonds. The rhES-QDs-M microspheres (rhES-QDs-M-MS) were prepared using electrostatic spray technology and also evaluated via in vivo imaging techniques. The pharmacodynamics was further studied in mice. The rhES-QDs-M-MS (4-8 μm) were stable in an aqueous medium with good optical properties. The in vitro studies showed that the rhES-QDs-M-MS had sustained release which was maintained for at least 15 days (cumulative release >80%) without any burst release. The rhES-QDs-M-MS had a very high safety profile and also effectively inhibited the in vitro proliferation of human umbilical vein endothelial cells by about 70%. The pharmacokinetic results showed that the rhES could still be detected at 72 h in the experimental group which meant that the rhES-QDs-M-MS had a significant sustained-release effect. The rhES-QDs-M-MS had a better lung targeting effect and higher antitumor activity compared with the rhES. The traceable rhES-QDs-M-MS served as a promising drug delivery system for the poorly stable rhES proteins and significantly increased its lung-targeted effect, sustained-release properties, and antitumor activities.

Efficacy and safety of recombinant human endostatin during peri-radiotherapy period in advanced non-small-cell lung cancer

Background: This study aimed to retrospectively investigate the efficacy and safety of recombinant human endostatin (Rh-endostatin) combined with radiotherapy in advanced non-small-cell lung cancer (NSCLC). Methods: Patients with unresectable stage III and IV NSCLC who treated with radiotherapy were enrolled. Patients who received Rh-endostatin infusion throughout the whole peri-radiotherapy period formed the Endostar group, and those who received no Rh-endostatin infusion were the control group. Results: The median progression-free survival was 8.0 and 4.4 months (hazard ratio: 0.53; 95% CI: 0.32-0.90; p = 0.019) and median overall survival was 40.0 and 13.1 months (hazard ratio: 0.53; 95% CI: 0.28-0.98; p = 0.045) for the Endostar and control groups, respectively. The Endostar group exhibited a numerically lower rate of radiation pneumonitis relapse, radiation pneumonitis death and pulmonary fibrosis. Conclusion: Rh-endostatin infusion throughout the peri-radiotherapy period enhanced radiosensitivity and showed better survival outcomes and a tendency toward fewer radiation-related pulmonary events in patients with NSCLC.

Clinical effects of cisplatin plus recombinant human endostatin (rh-endostatin) intratumoral injection on malignant central airway obstruction: a retrospective analysis of 319 cases

Background

Primary lung cancer with severe central airway obstruction (CAO) is often life-threatening. In this study, we investigated the clinical efficacy and safety of cisplatin plus recombinant human endostatin (rh-endostatin) intratumoral injection in treatment of malignant central airway obstruction (MCAO) caused by primary squamous cell lung cancer.

Methods

We retrospectively analyzed patients with MCAO caused by primary squamous cell lung cancer treated with and without bronchoscopic intratumoral injection of cisplatin plus rh-endostatin between January 2007 and June 2016.

Results

A total of 206 patients received cisplatin plus rh-endostatin intratumoral injection, and 113 without injection. Dyspnea grade, degree of stenosis, quality of life and lung function of all patients were significantly improved at 1 week after treatment compared with baseline. Both groups achieved good airway patency (97.1% vs. 93.8%, P=0.156). Followed up at 2 months, all parameters were improved in the injection group compared with baseline, while no statistical differences were observed in the non-injection group (P>0.05). The injection group achieved airway patency in 155 (75.2%) of 206 patients, which was significantly superior to the non-injection group [20 (17.7%) of 113, P<0.001]. In addition, the restenosis rate of the injection group was lower compared with the non-injection group (22.5% vs. 81.1%, P<0.001, respectively). No serious complications were observed in two groups.

Conclusions

Cisplatin plus rh-endostatin intratumoral injection is effective and safe for the therapy of MCAO caused by primary squamous cell lung cancer.

Efficacy of the combination of endostar with chemotherapy on stage IVb and recurrent metastatic cervical cancer

OBJECTIVES

To observe the efficacy and adverse reactions of the combination of endostar with chemotherapy in the treatment of advanced (IVb) and recurrent metastatic cervical cancer.

METHODS

Forty-four patients with recurrent and metastatic cervical cancer, who were admitted to the Second Xiangya Hospital, Central South University from December 2016 to December 2018 were randomly divided into an experimental group and a control group (22 cases in each group). The control group was given gemcitabine plus cisplatin (GP) or docetaxel plus cisplatin (DP) treatment, the experimental group was treated with endostar on the basis of the control group.

RESULTS

The objective response rate (ORR) was 42.9% in the experimental group and 22.7% in the control group. There was no significant difference between the 2 groups (P=0.371). The disease control rate (DCR) was 76.2% in the experimental group and 68.2% in the control group. There was no significant difference between the 2 groups (P=0.558). The effect of combined endostar was doubled compared with the effect of non-combination (50.0% vs 27.3% and 36.4% vs 18.2%), but there was no significant difference (P>0.05). Subgroup analysis found no significant difference in DP/GP with or without endostar on DCR (80.0% vs 72.7%, 72.7% vs 63.6%, P>0.05, respectively). The median progression-free survival of the experimental group and the control group were 7.2 months and 5.1 months, respectively, and the difference was statistically significant (P=0.036). The 2 groups mainly showed that the 3-4 adverse reaction was myelosuppression. The incidence of neutropenia of grade III-IV in the experimental group and the control group were 54.5% and 50.0%, respectively, and there was no statistical difference (P>0.05). The incidence of cardiovascular toxicity was higher in the experimental group than that in the control group (13.6% vs 0), but there was no significant difference between the 2 groups (P=0.233).

CONCLUSIONS

Compared with chemotherapy alone, endostar combined with chemotherapy can prolong the median progression-free survival, with higher ORR and similar adverse reactions.

TSP-1 as a novel biological marker of tumor vasculature normalization in colon carcinoma induced by Endostar

Blood vessels in tumors often exhibit abnormal morphology and function, which promotes the growth, metastasis and resistance of tumors to conventional therapies. Therefore, vascular normalization is an emerging strategy to enhance the effectiveness of radiotherapy and chemotherapy when used in combination; however, there is a lack of evidence regarding the optimal schedule for the co-administration of anti-angiogenic and chemotherapeutic drugs. Scheduling treatment is important as the period for normalization is transient, also known as the ‘time window’; however, no biomarker has been identified to detect this window. In the present study, recombinant human endostatin (rhES) was employed as an anti-angiogenic agent in xenograft tumor tissue in mice. Following rhES or control (saline) treatment, the density and integrity of tumor vessels were detected by immunofluorescence staining for cluster of differentiation 31 and α-smooth muscle actin; the level of hypoxia in tumor tissue was examined by immunohistochemistry with pimonidazole; the necrotic area was evaluated by hematoxylin and eosin staining; and the level of thrombospondin-1 (TSP-1) in plasma was tested by ELISA. The Cell Counting Kit-8 assay was also used to evaluate the effect of rhES on the proliferation of colon carcinoma SW620 cells. A ‘time window’ normalized vasculature was determined between day 4 and 6 following rhES treatment, and accompanied by a decrease in hypoxia in tumor tissue. Decreasing plasma TSP-1 levels were consistent with changes in vascular morphology and hypoxia, which exhibited features of normalization. In addition, rhES had no effect on the proliferation of SW620 cells, suggesting that the reduction in TSP-1 was associated with increased oxygen content during vascular normalization, rather than inhibited cell proliferation. In conclusion, TSP-1 may be a potential biomarker for predicting the normalization window of colon cancer vessels.

Different administration routes of recombinant human endostatin combined with concurrent chemoradiotherapy might lead to different efficacy and safety profile in unresectable stage III non-small cell lung cancer: Updated follow-up results from two phase II trials

Background

There are two main choices of administration route of recombinant human endostatin (Endostar) available and the treatment options of concurrent chemoradiotherapy (CCRT) have changed over time. The aim of this study was to observe the long‐term efficacy and safety of different administration routes of Endostar combined with CCRT.

Methods

Patients with unresectable stage III non‐small cell lung cancer (NSCLC) from two phase II trials were included as two cohorts. Both were treated with Endostar combined with CCRT. Endostar was administrated by intravenous injection (7.5 mg/m²/day, seven days) in the IV arm and by continuous intravenous pumping (7.5 mg/m²/24 hours, 120 hours) in the CIV arm.

Results

A total of 48 patients were included in the IV arm and 67 patients in the CIV arm. The median progression‐free survival (PFS), overall survival (OS), local recurrence‐free survival (LRFS) and distant metastasis‐free survival (DMFS) in the IV arm and CIV arm were 9.9 months versus 15.4 months (HR = 0.751, 95% CI 0.487–1.160, P = 0.200), 24.0 months versus 38.5 months (HR = 0.746, 95% CI 0.473–1.178, P = 0.209), 32.3 months versus 27.1 months (HR = 1.193, 95% CI 0.673–2.115, P = 0.546), 20.1 months versus 49.7 months (HR = 0.603, 95% CI 0.351–1.036, P = 0.067). The one, three, five‐year PFS in the IV arm and CIV arm was 45.8% versus 52.9%, 18.3% versus 31.4%, and 18.3% versus 27.7% and the one, three, five‐year OS was 81.2% versus 82.1%, 31.1% versus 50.3%, and 31.1% versus 41%, respectively. Incidence of hematological adverse reactions were numerically lower in the CIV arm than the IV arm.

Conclusions

Endostar delivered by CIV with CCRT may be a better option than IV in terms of potential survival and safety for unresectable stage III NSCLC.

Key points

Significant findings of the study Endostar delivered by continuous intravenous pumping might achieve more favorable survival over intravenous injection and reduce adverse hematological reactions in patients with unresectable stage III NSCLC treated with Endostar combined with CCRT.What this study adds The administration route of recombinant human endostatin is also one key factor for survival and safety to consider when treating patients with unresectable stage III NSCLC.

Biophysical and biological characterization of PEGylated recombinant human endostatin

Recombinant human endostatin (MES), showing potent inhibition on angiogenesis and tumour growth, has great potential as a therapeutic agent for tumours. The aim of this study was to evaluate the biophysical and biological characterization of PEGylated recombinant human endostatin (M₂ ES). Recombinant human endostatin was mono-PEGylated by conjugation with methoxy polyethylene glycol aldehyde (mPEG-ALD), and the modification site was identified by digested peptide mapping and matrix assisted laser desorption/ionization-time of flight-mass spectrometry (MALDI-TOF-MS). The purity was assessed by SDS-PAGE, high-performance liquid chromatography (HPLC), and capillary zone electrophoresis. The physicochemical property was analyzed through fluorescence spectroscopy, and circular dichroism. The bioactivity and anti-tumour efficacy of M₂ ES were evaluated using an in vitro endothelial cell migration model and a null-mouse xenograft model of a prostatic cancer, respectively. M₂ ES molecules contain a single 20 kDa mPEG-ALD molecule conjugated at the N-terminal portion of MES. The purity of M₂ ES was greater than 98%. The physicochemical analysis demonstrated that PEGylation does not change the secondary and tertiary structure of MES. Notably, M₂ ES retards endothelial cell migration and tumour growth when compared to control group. These biophysical and biological characterization study data contribute to the initiation of the ongoing clinical study.

Antitumor effects of Endostar(rh-endostatin) combined with gemcitabine in different administration sequences to treat Lewis lung carcinoma

Background: Endostatin therapy is known to efficiently inhibit angiogenesis and growth of endothelial cells. Nonetheless, the antitumor mechanisms of endostatin combined with chemotherapy remain to be elucidated. Methods: In our study, a Lewis lung carcinoma transplant mouse model was established and treated with the recombinant human [rh]-endostatin, Endostar, combined with gemcitabine at different sequences. 18F-FDG PET/CT imaging was performed to monitor tumor growth, and hypoxia was examined using an oxygen microelectrode. Vascular endothelial growth factor (VEGF) and alpha smooth muscle actin (α-SMA) levels were detected via immunohistochemistry analysis and cell cycle distributions were analyzed by flow cytometry. Results: Endostar decreased VEGF expression, improved hypoxia, and influenced cell cycle distributions. Simultaneous treatment of Endostar and gemcitabine displayed significantly tumor inhibition, possessed the lowest uptake of FDG, improved oxygen partial pressure, decreased expression of VEGF, and increased pericyte coverage. Cell cycle analysis demonstrated that cells accumulated in the S phase following gemcitabine treatment and G0/G1 arrest occurred following Endostar treatment. An increase of cells in G0/G1 phase was observed following treatment with Endostar and gemcitabine. Conclusions: Our study suggests that the combination therapy of Endostar with gemcitabine simutaneously may optimally enhance their individual antitumor effects.

Clinical observation of recombinant human endostatin in treating relapsed refractory multiple myeloma

Recombinant human endostatin (rhES) can inhibit multiple myeloma, while its clinical efficacy in treating relapsed refractory multiple myeloma (RRMM) has not been assessed. One hundred and eleven RRMM patients were treated with four different regimens: combination of VD (velcade+dexamethasone) and rhES (n = 25), Thalidomide (Tha) and VD (VTD, n = 22) combination, rhES and conventional chemotherapy combination (n = 32), and combination of conventional chemotherapy and Tha (n = 32). Significant differences were found in progression-free survival (PFS) between rhES combination groups and conventional chemotherapy combination groups. No statistical difference was found in overall response rate, overall survival or incidences of adverse effects. The combination of rhES with VD or conventional chemotherapy is active in patients with RRMM and prolongs the PFS to improve the quality of life.

Influence of different drug delivery methods for Endostar combined with a gemcitabine/cisplatin regimen in locally advanced or metastatic lung squamous cell carcinoma: A retrospective observational study

Continuous endovenous administration of Endostar (CE) gradually replaced drip intravenous administration of Endostar (DE) in lung squamous cell carcinoma (SCC) treatment presently, but the efficacy and safety of CE and DE which is better in advanced lung SCC are yet unclear. To evaluate the feasibility of CE as an alternative to DE with gemcitabine/cisplatin (GP) chemotherapy. Data were collected from patients admitted with locally advanced or metastatic lung SCC from January 2011 to April 2015, including the patients' characteristics, the therapeutic regimen, the treatment effectiveness, and toxicity. There are 71 patients with pathologically confirmed lung SCC retrospectively assigned to a treatment (CE) group of 48 patients and a control (DE) group of 23 patients. The response of each tumor to the therapy was assessed every 2 cycles by a chest and upper abdomen computed tomography for the comparison of curative effects and adverse reactions. Compared with the DE group, the response rate and disease control rate were noninferior in the CE group. The median progression-free survival and overall survival in the CE and DE groups were no significantly difference (5.5 vs 5.5 months, P = .141; 22.9 vs 14.3 months, P = .053). Increased progression-free survival (PFS) for patients in CE group was observed across 3 subgroups analyzed. There was a 35.7% reduction in the total dose of Endostar per cycle in the CE group compared with that in the DE group. Thus, in combination with GP chemotherapy, CE could be a suitable alternative to DE in locally advanced or metastatic SCC patients, resulting in less hemoptysis, less treatment time, and lower costs.

Intensity-modulated radiotherapy combined with endostar has similar efficacy but weaker acute adverse reactions than IMRT combined with chemotherapy in the treatment of locally advanced nasopharyngeal carcinoma

The present study is to compare the efficacy and adverse effects of intensity-modulated radiotherapy (IMRT) combined with endostar and IMRT combined with concurrent chemotherapy on locally advanced nasopharyngeal carcinoma (NPC).A total of 23 patients with stage III-IVa NPC were included in the present study, and randomly divided into experimental group (10 cases treated with IMRT + endostar) and control group (13 cases treated with IMRT + chemotherapy of cis-dichlorodiamineplatinum). Endostar was intravenously administered from the first day of IMRT. The patients received a total of 2 cycles (14 days each) separating by a 7-day interval.IMRT combined with endostar did not have significantly different recent efficacy compared with IMRT combined with chemotherapy. IMRT combined with endostar and IMRT combined with chemotherapy had 2-year overall survival (OS) rates of 100.0% and 69.6%, respectively, without significant difference between each other (χ = 1.446, P = .299). The 2-year local relapse-free survival (LRFS) of the 2 groups were 100.0% and 81.3%, respectively, without significant difference between each other (χ = 1.000, P = .317). The 2-year distant metastasis-free survival (DMFS) of the 2 groups were 100.0% and 73.5% (χ = 1.591, P = .207), respectively. The 2-year progression-free survival (PFS) of the 2 groups were 100.0% and 67.3% (χ = 2.164, P = .141), respectively. However, the cumulative survival curves of OS, LRFS, DMFS, and PFS were separated between the 2 groups. The result that IMRT combined with endostar did not have significantly different long-term efficacy than IMRT combined with chemotherapy probably due to limited case number and short follow-up time. IMRT combined with endostar resulted in significantly lower grades of leucopenia, nausea/vomiting, weight loss, and oral mucositis compared with IMRT combined with chemotherapy. The grades of late adverse reactions of IMRT combined with endostar were not different from those of IMRT combined with chemotherapy.The present study demonstrates that, compared with IMRT combined with chemotherapy, IMRT combined with endostar has similar efficacy in the treatment of locally advanced NPC, but significantly weaker acute adverse reactions, which improve the life quality of NPC patients.

Combining antiangiogenic therapy with neoadjuvant chemotherapy increases treatment efficacy in stage IIIA (N2) non-small cell lung cancer without increasing adverse effects

To evaluate the safety and efficacy of combining Endostar antiangiogenic therapy with neoadjuvant chemotherapy for the treatment of stage IIIA (N2) NSCLC, we conducted a randomized, controlled, open-label clinical study of 30 NSCLC patients. Patients were randomly assigned to the test or control groups, which received either two cycles of an NP neoadjuvant chemotherapy regimen combined with Endostar or the NP regimen alone, respectively, at a 2:1 ratio. Efficacy was assessed after 3 weeks, and surgical resection occurred within 4 weeks, in the 26 patients who successfully completed treatment. While total response rates (RR) and clinical benefit rates (CBR) did not differ between the experimental groups, total tumor regression rates (TRR) were higher in the test group than in the control group. Median DFS and OS also did not differ between the test and control groups. Clinical perioperative indicators, including intraoperative blood loss, number of dissected lymph node groups, duration of postoperative indwelling catheter use, and time to postoperative discharge, were comparable in the test and control groups. Finally, hematological and non-hematological toxicities and postoperative pathological indicators, including down-staging ratio, complete resection ratio, and metastatic lymph node ratio, also did not differ between the groups. Overall, combining Endostar with NP neoadjuvant chemotherapy increased therapeutic efficacy without increasing adverse effects in stage IIIA-N2 NSCLC patients. This study is registered with ClinicalTrials.gov (number NCT02497118).

Conjugation of gold nanoparticles and recombinant human endostatin modulates vascular normalization via interruption of anterior gradient 2-mediated angiogenesis

Several studies have revealed the potential of normalizing tumor vessels in anti-angiogenic treatment. Recombinant human endostatin is an anti-angiogenic agent which has been applied in clinical tumor treatment. Our previous research indicated that gold nanoparticles could be a nanoparticle carrier for recombinant human endostatin delivery. The recombinant human endostatin-gold nanoparticle conjugates normalized vessels, which improved chemotherapy. However, the mechanism of recombinant human endostatin-gold nanoparticle-induced vascular normalization has not been explored. Anterior gradient 2 has been reported to be over-expressed in many malignant tumors and involved in tumor angiogenesis. To date, the precise efficacy of recombinant human endostatin-gold nanoparticles on anterior gradient 2-mediated angiogenesis or anterior gradient 2-related signaling cohort remained unknown. In this study, we aimed to explore whether recombinant human endostatin-gold nanoparticles could normalize vessels in metastatic colorectal cancer xenografts, and we further elucidated whether recombinant human endostatin-gold nanoparticles could interrupt anterior gradient 2-induced angiogenesis. In vivo, it was indicated that recombinant human endostatin-gold nanoparticles increased pericyte expression while inhibit vascular endothelial growth factor receptor 2 and anterior gradient 2 expression in metastatic colorectal cancer xenografts. In vitro, we uncovered that recombinant human endostatin-gold nanoparticles reduced cell migration and tube formation induced by anterior gradient 2 in human umbilical vein endothelial cells. Treatment with recombinant human endostatin-gold nanoparticles attenuated anterior gradient 2-mediated activation of MMP2, cMyc, VE-cadherin, phosphorylation of p38, and extracellular signal-regulated protein kinases 1 and 2 (ERK1/2) in human umbilical vein endothelial cells. Our findings demonstrated recombinant human endostatin-gold nanoparticles might normalize vessels by interfering anterior gradient 2-mediated angiogenesis in metastatic colorectal cancer.

Expression of Inhibitor of Differentiation-1 and Its Effects on Angiogenesis in Gastric Cancer

OBJECTIVE

To explore the effects of recombinant human endostatin (endostar, ES) and cisplatin on the growth of gastric cancer-transplanted tumor in nude mice and the expression of microvessel density (MVD).

METHODS

Human gastric cancer SGC-7901 cells were subcutaneously injected into the armpit of nude mice to prepare cancer-bearing nude mice. A total of 32 cancer-bearing nude mice were divided into four groups (each group with 8 mice). The four groups included control group and other three groups in which mice were treated with 5 mg/kg of ES (group E), 5 mg/kg of cisplatin (group Ci), and 5 mg/kg of ES combined with 5 mg/kg of cisplatin (group C), respectively. MVD was determined by immunohistochemistry, and the expressions of mRNA and protein of inhibitor of differentiation-1 (ID1) and vascular endothelial growth factor (VEGF) were detected with reverse transcription polymerase chain reaction (RT-PCR) and western blot, respectively. Apoptosis was observed with transmission electron microscope.

RESULTS

Compared with control group, the sizes and weights of tumors were significantly decreased in other three groups (all p < 0.05). MVD was significantly lower in groups E, Ci, and C than in control group, and in groups E and C than in group Ci (all p < 0.05). Compared with control group, the expressions of mRNA and protein of ID1 and VEGF significantly decreased in groups E and C (all p < 0.05). There were no significant differences in the expressions of mRNA and protein of ID1 and VEGF between group Ci and control group. There was apoptosis in groups E and C, but no apoptosis was found in group Ci and control group.

CONCLUSION

ES can inhibit the growth of gastric cancer cells through suppressing angiogenesis and promoting apoptosis of tumor cell. This study provides a new idea for the treatment of gastric cancer.

Recombinant human endostatin in combination with CHOP regimen for peripheral T cell lymphoma

Peripheral T cell lymphoma (PTCL) has a poor prognosis. Overexpression of vascular endothelial growth factor (VEGF) might contribute to the poor prognosis of PTCL and could be the target of novel therapy. The efficacy and safety of recombinant human endostatin (Endostar) in combination with cyclophosphamide, doxorubicin, vincristine and prednisone (ECHOP) have been explored in 15 PTCL patients. The objective response rate was 80%, with 53.3% patients having achieved complete response (CR) rate. The CR rate was 100% (3/3) in angioimmunoblastic T cell lymphoma (AITL) patients compared to only 36.4% (4/11) in PTCL not otherwise specified (PTCL-NOS) patients. With a median follow-up of 69 months, the 5-year progression-free survival and overall survival (OS) were 53% and 60%, respectively. The 5-year OS was 100% in AITL but was only 45% in PTCL-NOS. Seven out of 11 patients showed overexpression of VEGFR2 in their tumor vessels and had a better efficacy than those with low expression of VEGFR2. Grade 3 or 4 neutropenia is the most common toxicity observed. ECHOP was safe and might display potential benefit in AITL patients.

Usefulness of dynamic contrast-enhanced magnetic resonance imaging for predicting treatment response to vinorelbine-cisplatin with or without recombinant human endostatin in bone metastasis of non-small cell lung cancer

Metastatic bone disease is a frequent complication of advanced non-small cell lung cancer (NSCLC) and causes skeletal-related events, which result in a poor prognosis. Currently, no standard method has been developed to precisely assess the therapeutic response of bone metastases (BM) and the early efficacy of anti-angiogenic therapy, which does not conform to the concept of precision medicine. This study aimed to investigate the usefulness of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) for precise evaluation of the response to chemotherapy with anti-angiogenic agents in NSCLC patients with BM. Patients were randomly assigned to a treatment group (vinorelbine + cisplatin [NP] + recombinant human endostatin [rh-endostatin]) or a control group (NP + placebo). All patients were evaluated before treatment and after 2 cycles of treatment using DCE-MRI quantitative analysis technology for BM lesions and chest computed tomography (CT). Correlations between changes in the DCE-MRI quantitative parameters and treatment effect were analyzed. We enrolled 33 patients, of whom 28 were evaluable (20 in the treatment group and 8 in the control group). The results suggested a higher objective response rate (30% vs. 0%), better overall survival (21.44 ± 17.28 months vs. 7.71 ± 4.68 months), and a greater decrease in the transport constant (Ktrans) value (60% vs. 4.4%) in the treatment group than in the control group (P < 0.05). The Ktrans values in the "partial remission plus stable disease (PR + SD)" group were significantly lower after treatment (P < 0.05). Patients with a decrease of > 50% in the Ktrans value showed a significantly better overall survival than those with a decrease of ≤ 50% (13.2 vs. 9.8 months, P < 0.05). Ktrans as a DEC-MRI quantitative parameter could be used for the precise evaluation of BM lesions after anti-angiogenic therapy and as a predictor of survival. In addition, we reconfirmed the anti-angiogenic effect of rh-endostatin in NSCLC patients with BM.

The accumulation of macrophages attenuates the effect of recombinant human endostatin on lung cancer

Background

Although anti-angiogenic therapy is widely applied clinically, its efficacy has been less than expected. Screening for regulatory factors and sensitive indicators to define the effectiveness of these drugs is required. Through a retrospective study of clinical data, we found that patients with a higher peripheral monocyte-to-lymphocyte ratio (MLR) obtained less benefit from recombinant human endostatin (rhES, Endostar^®), an anti-angiogenic drug, in lung cancer. Because MLR is positively correlated with macrophage count in tumors, this result suggests that macrophages may influence the effectiveness of rhES therapy in lung cancer.

Methods

Clinical data from 72 lung cancer patients treated with rhES were collected. Animal study, flow cytometry, immunofluorescence, enzyme-linked immunosorbent assay, Western blot analysis, and transwell migration assays were carried on Lewis lung carcinoma (LLC) cells, bone marrow-derived macrophages, macrophage cell line RAW264.7, and ANA-1 cells.

Results

Clinical data showed that compared with the baseline MLR before rhES treatment, patients with progressive disease had higher MLRs than those of patients with partial response. Experimental results showed that more macrophages were recruited in the LLC tumors after rhES treatment and the majority of them displayed an M2-like phenotype. rhES aggravated hypoxia and the inflammatory response in the tumor microenvironment. Hypoxia promoted the expression of CCL2 by endothelial and fibroblast cells, which could induce macrophages recruitment, and increased levels of inflammatory cytokines (interleukin-4 [IL-4], IL-6, and IL-10) skewed macrophage polarization toward the M2-like phenotype. Hypoxia or inflammation cytokine-treated macrophages enhanced the progression of LLC in vitro and in vivo.

Conclusion

We found rhES could aggravate hypoxia and the inflammatory response in the tumor microenvironment. These changes were favorable for macrophage accumulation, and skewed their polarization toward the M2-like phenotype which could help LLC to escape from the anti-angiogenic therapy. Thus, these data indicate the accumulation of macrophages in the tumor microenvironment may adversely affect the efficacy of rhES on lung cancer.

Recombinant Human Endostatin Suppresses Mouse Osteoclast Formation by Inhibiting the NF-κB and MAPKs Signaling Pathways

Rheumatoid arthritis is an autoimmune disease characterized by synovial hyperplasia and progressive joint destruction. As reported previously, recombinant human endostatin (rhEndostatin) is associated with inhibition of joint bone destruction present in rat adjuvant-induced arthritis; however, the effect of rhEndostatin on bone destruction is not known. This study was designed to assess the inhibitory effect and mechanisms of rhEndostatin on formation and function of osteoclasts in vitro, and to gain insight into the mechanism underlying the inhibitory effect of bone destruction. Bone marrow-derived macrophages isolated from BALB/c mice were stimulated with receptor activator of NF-κB ligand (RANKL) and macrophage colony-stimulating factor to establish osteoclast formation. Osteoclast formation was determined by TRAP staining. Cell viability of BMMs affected by rhEndostatin was determined using a MTT assay. Bone resorption was examined with a bone resorption pits assay. The expression of osteoclast-specific markers was analyzed using quantitative real-time PCR. The related signaling pathways were examined using a Luciferase reporter assay and western blot analysis. Indeed, rhEndostatin showed a significant reduction in the number of osteoclast-like cells and early-stage bone resorption. Moreover, molecular analysis demonstrated that rhEndostatin attenuated RANKL-induced NF-κB signaling by inhibiting the phosphorylation of IκBα and NF-κB p65 nuclear translocation. Furthermore, rhEndostatin significantly inhibited the activation of RANKL-dependent mitogen-activated protein kinases, such as ERK1/2, JNK, and p38. Hence, we demonstrated for the first time that preventing the formation and function of osteoclasts is an important anti-bone destruction mechanism of rhEndostatin, which might be useful in the prevention and treatment of bone destruction in RA.

Lung cancer cellular apoptosis induced by recombinant human endostatin gold nanoshell-mediated near-infrared thermal therapy

AIMS AND BACKGROUND

Endostatin can inhibit tumor endothelial cell proliferation, angiogenesis, and growth. We aimed to determine the increase in antitumor capabilities of recombinant human endostatin (rhES) when used with a nanocarrier system. The effect of gold nanoshell particles of recombinant human endostatin (G-rhES) with near-infrared (NIR) irradiation on proliferation, inhibition, and apoptosis of A549 lung cancer cells was studied.

MATERIALS AND METHODS

Gold nanoshell particles were prepared. Endostatin was connected with the bond A-U through surface modification by bioconjugation of core-shell structured gold nanoshells. The drug targeting endostatin and the synthesized G-rhES were successfully connected. G-rhES inhibited proliferation of A549 lung cancer cells, as detected using tetrazolium colorimetric assay. Cellular apoptosis was measured by flow cytometry. Mitochondrial membrane potential was determined using a confocal microscope. Morphological changes were studied by atomic force microscopy.

RESULTS

Under irradiation in the 820 nm NIR, G-rhES significantly inhibited the proliferation of A549 lung cancer cells. The underlying mechanism may be related to heat-induced apoptosis and cytotoxicity by NIR absorption, which kills cells directly, thereby indicating that G-rhES have good biocompatibility and pharmacological potency. Characterization of the local structure of lung cancer cells showed that G-rhES targeted surface receptors that may serve an apoptotic function under NIR exposure. NIR gold nanoshell particles showed synergism with endostatin, which may be related to hyperthermia-increased cytotoxicity and the apoptotic effect of endostatin.

CONCLUSION

These data suggest that G-rhES can enhance the inhibition of tumor growth. The new treatment strategy of G-rhES combined with thermal therapy may lead to lung cancer remission. The potential benefits of G-rhES are being considered for clinical evaluation.

Effects of recombinant human endostatin on the expression of vascular endothelial growth factor in human gastric cancer cell line MGC-803

The present study aimed to explore the effects of recombinant human endostatin, endostar (ES), on the expression of vascular endothelial growth factor (VEGF) in the human gastric cancer cell line MGC-803. The expression of VEGF protein in MGC-803 cells was examined using immunohistochemistry. Subsequent to treatment with various concentrations of ES, the mRNA and VEGF protein expressions were determined in MGC-803 cells. A high level of VEGF protein expression was detected in MGC-803 cells. Subsequent to ES treatment, the mRNA and VEGF protein expressions were significantly decreased in MGC-803 cells (all P<0.05). In conclusion, ES is likely to inhibit the VEGF expression in MGC-803 cells.

Synergistic effects of Endostar combined with β-elemene on malignant ascites in a mouse model

To explore an effective combination therapy for malignant ascites, the therapeutic value of the combination of Endostar, a modified recombinant human endostatin, and β-elemene, an active component of a traditional Chinese herb, in an H22 mouse malignant ascites model was investigated. The optimal dose combination of Endostar and β-elemene was determined by evaluating the inhibition of ascites volume and increase in the survival rate of the mice. Other therapeutic effects and the underlying mechanisms were investigated under the optimal dose combination (8 mg/kg Endostar plus 100 mg/kg β-elemene). The mice were randomly divided into four treatment groups and received intraperitoneal injection once a day for eight days: control (0.9% normal saline), Endostar (8 mg/kg), β-elemene (100 mg/kg) or optimal dose combination (8 mg/kg Endostar plus 100 mg/kg β-elemene), respectively. The results of this study revealed that the combination therapy had significant synergistic effects on the inhibition of ascites formation and a deceased number of tumor cells and protein levels in ascites compared with the results of treatment with a single agent. A decreased peritoneal microvascular permeability and reduction in VEGF, MMP-2 and hypoxia inducible factor 1α (HIF1α) was noted in the combination group, when compared with single agent treatment. These studies found that in the ascitic tumor cells, the protein levels of VEGF and MMP-2, as well as levels of VEGF mRNA, were significantly inhibited by the combination therapy. The potentiating effects of the combination of Endostar with β-elemene suggest that this novel therapy may yield an effective therapy for the treatment of malignant ascites.

Recombinant human endostatin endostar inhibits tumor growth and metastasis in a mouse xenograft model of colon cancer

To investigate the effects of recombinant human endostatin Endostar on metastasis and angiogenesis and lymphangiogenesis of colorectal cancer cells in a mouse xenograft model. Colon cancer cells SW620 were injected subcutaneously into the left hind flank of nude mice to establish mouse xenograft models. The mice were treated with normal saline or Endostar subcutaneously every other day. The growth and lymph node metastasis of tumor cells, angiogenesis and lymphangiogenesis in tumor tissue were detected. Apoptosis and cell cycle distribution were studied by flow cytometry. The expression of VEGF-A, -C, or -D in SW620 cells was determined by immunoblotting assays. Endostar inhibited tumor growth and the rate of lymph node metastasis (P < 0.01). The density of blood vessels in or around the tumor area was 12.27 ± 1.21 and 22.25 ± 2.69 per field in Endostar-treated mice and controls (P < 0.05), respectively. Endostar also decreased the density of lymphatic vessels in tumor tissues (7.84 ± 0.81 vs. 13.83 ± 1.08, P < 0.05). Endostar suppresses angiogenesis and lymphangiogenesis in the lymph nodes with metastases, simultaneously. The expression of VEGF-A, -C and -D in SW620 cells treated with Endostar was substantially lower than that of controls. Endostar inhibited growth and lymph node metastasis of colon cancer cells by inhibiting angiogenesis and lymphangiogenesis in a mouse xenograft model of colon cancer.

[Effects of recombinant human endostatin and docetaxel on MMP and its following anti-neoplastic effect under different administration sequences]

BACKGROUND AND OBJECTIVE

The aim of this study is to observe the changes of MMP-2 and its regulators, and to investigate the mechanism of the two administration sequences of recombinant human endostatin (rh-endostatin) and docetaxel.

METHODS

The experiment was performed as 2 stages. Firstly, nude mice with xenograft tumor were randomized into 2 groups as rh-endostatin-treated group with rh-endostatin 400 microg x d(-1), d1-d14 and docetaxel-traeted group with docetaxel 10 mg x kg(-1) x 3d(-1), d1-d14. Secondly, nude mice with xenograft tumor were randomized into 3 groups as concurrent administration group (rh-endostatin 400 microg x d(-1), d1-d35, docetaxel 10 mg x kg(-1) x 3d(-1), d1-d19), endo-first group (rh-endostatin 400 microg x d(-1), d1-d35, docetaxel 10 mg x kg(-1) x 3(d-1), d16-d34) and model group (positive control, mice burdened tumor without treatment). The volume of tumor was measured during treatment. Detection of the expressions of MMP-2, TIMP-2, EMMPRIN and the count of microvessel density (MVD) by immunohistochemistry stain examination were carried out at the end of experiment.

RESULTS

Compared with the docetaxel-treated group, more obvious down-regulation of expression of MMP-2, EMMPRIN (P = 0.024, P = 0.081) were observed in rh-endostatin-treated group. No significant difference was found in TIMP-2 expression between the 2 groups. In combined treatment groups, at the endpoint tumor volumes of concurrent administration group and the endo-first group were remarkably smaller than that in model group (P < 0.001, P = 0.003). According to the administration procedure, concurrent administration inhibited tumor growth stronger than endo-first treatment did. Both of the combined groups down-regulated the expression of MMP-2 and decreased microvessel density (P < 0.05). Compared with model group, the expression of TIMP-2 was upregulated (P = 0.001) as well as EMMPRIN down-regulated (P = 0.018) in concurrent adminis- tration group. Oppositely, the same results were not observed in the endo-first group.

CONCLUSION

The schedule of the concurrent administration group could inhibit the tumor growth better, and it down-regulated MMP-2 expression through TIMP-2 and EMMPRIN, and thus slow down the tumor growth superiorly to another schedule of treatment.