You Lu

Immunotherapy of tumors with xenogeneic endothelial cells as a vaccine.

The breaking of immune tolerance against autologous angiogenic endothelial cells should be a useful approach for cancer therapy. Here we show that immunotherapy of tumors using fixed xenogeneic whole endothelial cells as a vaccine was effective in affording protection from tumor growth, inducing regression of established tumors and prolonging survival of tumor-bearing mice. Furthermore, autoreactive immunity targeting to microvessels in solid tumors was induced and was probably responsible for the anti-tumor activity. These observations may provide a new vaccine strategy for cancer therapy through the induction of an autoimmune response against the tumor endothelium in a cross-reaction.

Gefitinib plus chemotherapy versus placebo plus chemotherapy in EGFR-mutation-positive non-small-cell lung cancer after progression on first-line gefitinib (IMPRESS): a phase 3 randomised trial

BACKGROUND Optimum management strategies for patients with advanced non-small-cell lung cancer (NSCLC) with acquired resistance to EGFR tyrosine-kinase inhibitors are undefined. We aimed to assess the efficacy and safety of continuing gefitinib combined with chemotherapy versus chemotherapy alone in patients with EGFR-mutation-positive advanced NSCLC with acquired resistance to first-line gefitinib. METHODS The randomised, phase 3, multicentre IMPRESS study was done in 71 centres in 11 countries in Europe and the Asia-Pacific region. Eligible patients were aged at least 18 years with histologically confirmed, chemotherapy-naive, stage IIIB-IV EGFR-mutation-positive advanced NSCLC with previous disease control with first-line gefitinib and recent disease progression (Response Evaluation Criteria in Solid Tumors version 1.1). Participants were randomly assigned (1:1) by central block randomisation to oral gefitinib 250 mg or placebo once daily in tablet form; randomisation did not include stratification factors. All patients also received the platinum-based doublet chemotherapy cisplatin 75 mg/m(2) plus pemetrexed 500 mg/m(2) on the first day of each cycle. After completion of a maximum of six chemotherapy cycles, patients continued their randomly assigned treatment until disease progression or another discontinuation criterion was met. All study investigators and participants were masked to treatment allocation. The primary endpoint was progression-free survival in the intention-to-treat population. Safety was assessed in patients who received at least one dose of study treatment. The study has completed enrolment, but patients are still in follow-up for overall survival. This trial is registered with ClinicalTrials.gov, number NCT01544179. FINDINGS Between March 29, 2012, and Dec 20, 2013, 265 patients were randomly assigned: 133 to the gefitinib group and 132 to the placebo group. At the time of data cutoff (May 5, 2014), 98 (74%) patients had disease progression in the gefitinib group compared with 107 (81%) in the placebo group (hazard ratio 0·86, 95% CI 0·65-1·13; p=0·27; median progression-free survival 5·4 months in both groups [95% CI 4·5-5·7 in the gefitinib group and 4·6-5·5 in the placebo group]). The most common adverse events of any grade were nausea (85 [64%] of 132 patients in the gefitinib group and 81 [61%] of 132 patients in the placebo group) and decreased appetite (65 [49%] and 45 [34%]). The most common adverse events of grade 3 or worse were anaemia (11 [8%] of 132 patients in the gefitinib group and five [4%] of 132 patients in the placebo group) and neutropenia (nine [7%] and seven [5%]). 37 (28%) of 132 patients in the gefitinib group and 28 (21%) of 132 patients in the placebo group reported serious adverse events. INTERPRETATION Continuation of gefitinib after radiological disease progression on first-line gefitinib did not prolong progression-free survival in patients who received platinum-based doublet chemotherapy as subsequent line of treatment. Platinum-based doublet chemotherapy remains the standard of care in this setting. FUNDING AstraZeneca.

Immunogene therapy of tumors with vaccine based on Xenopus homologous vascular endothelial growth factor as a model antigen

Overcoming immune tolerance of the growth factors associated with tumor growth should be a useful approach to cancer therapy by active immunity. We used vascular endothelial growth factor (VEGF) as a model antigen to explore the feasibility of the immunogene tumor therapy with a vaccine based on a single xenogeneic homologous gene, targeting the growth factors associated with angiogenesis. To test this concept, we constructed a plasmid DNA encoding Xenopus homologous VEGF (XVEGF-p) and control vectors. We found that immunogene tumor therapy with a vaccine based on XVEGF was effective at both protective and therapeutic antitumor immunity in several tumor models in mice. VEGF-specific autoantibodies in sera of mice immunized with XVEGF-p could be found in Western blotting analysis and ELISA assay. The purified immunoglobulins were effective at the inhibition of VEGF-mediated endothelial cell proliferation in vitro, and at antitumor activity and the inhibition of angiogenesis by adoptive transfer in vivo. The elevation of VEGF in the sera of the tumor-bearing mice could be abrogated with XVEGF-p immunization. The antitumor activity and production of VEGF-specific autoantibodies, significantly elevated IgG1 and IgG2b, could be abrogated by the depletion of CD4+ T lymphocytes. The observations may provide a vaccine strategy for cancer therapy through the induction of autoimmunity against the growth factors associated with tumor growth in a cross reaction with single xenogeneic homologous gene and may be of importance in the further exploration of the applications of other xenogeneic homologous genes identified in human and other animal genome sequence projects in cancer therapy.

Transcatheter arterial chemoembolization in combination with radiotherapy for unresectable hepatocellular carcinoma: a systematic review and meta-analysis.

BACKGROUND AND PURPOSE To evaluate the efficacy and safety of transcatheter arterial chemoembolization (TACE) plus radiotherapy (RT) for unresectable hepatocellular carcinoma (UHCC) using meta-analysis of data from the literature involving available randomized controlled trials of TACE in combination with RT compared with that of TACE alone (Therapy I versus II) in treating UHCC. MATERIAL AND METHODS We searched the Cochrane Library, MEDLINE, CENTRAL, EMBASE, CBMdisc, and CNKI as well as employing manual searches. Meta-analysis was performed on the results of homogeneous studies. Analyses subdivided by study design were also performed. RESULTS We found 17 trials involving 1476 patients. 5 of total were Randomized Controlled Trials (RCTs) and 12 were Non-randomized Controlled Clinical Trials (CCTs). In terms of quality, 5 RCTs were graded B, and 12 CCTs were graded C. Our results showed that Therapy I, compared with Therapy II, significantly improved the survival and the tumor response of patients, and was thus more therapeutically beneficial. Serious adverse events were not increased exception for total bilirubin (TB) level. CONCLUSIONS Therapy I was more therapeutically beneficial. However, considering the strength of the evidence, additional randomized controlled trials are needed before Therapy I can be recommended routinely.

Induction of apoptosis by norcantharidin in human colorectal carcinoma cell lines: involvement of the CD95 receptor/ligand

Abstract.Purpose: Cantharidin, a natural toxin, is the active substance of mylabris and has antitumor effects in man. Norcantharidin, the demethylated analogue of cantharidin, has been used in the treatment of patients with primary hepatoma and those with leukopenia in China. The present study was designed to investigate whether norcantharidin exerts cytotoxic activity against colorectal cancer cells by inducing apoptosis and to examine the possible mechanism in the phenomenon. Methods: Inhibition of proliferation of norcantharidin on Colo205, HT-29, and SW480 colorectal cancer cells was determined by the trypan blue dye exclusion test. Apoptosis of norcantharidin-treated cells was determined by morphological analysis, agarose gel DNA electrophoresis, and quantitated by flow cytometry after staining with propidium iodide. Cell cycle and the cell surface expression of the CD95/CD95 ligand were evaluated by flow cytometry. Caspase 8-like protease and protein phosphatase 1 and 2A activities were also analyzed. Results: Treatment with norcantharidin of colorectal cancer cells not only inhibited cell proliferation, but also induced apoptosis. Norcantharidin induced apoptosis mainly in two phases: rapid apoptosis in S-phase cells and delayed apoptosis in G2/M arrested cells. Treatment with norcantharidin resulted in an upregulation of the CD95 receptor and CD95 ligand on the cell surface. Furthermore, stimulation with anti-CD95 monoclonal antibody (mAb) resulted in further induction of apoptosis after treatment with norcantharidin. In addition, the apoptosis-inducing effect of norcantharidin was almost completely inhibited by anti-CD95 ligand mAb. Norcantharidin-treated cells showed the activation of caspase 8. Both zVAD-FMK (a broad range caspase inhibitor) and IETD-FMK (a caspase-8 inhibitor) showed apparent inhibition of the apoptosis-inducing effect. Norcantharidin did not show an inhibitory effect on protein phosphatase. Conclusions: These results suggest that norcantharidin triggers apoptosis in colorectal cancer cell lines via the activation of the CD95 receptor/ligand system, and that this agent may be useful for developing new therapeutic regimens for the treatment of colorectal carcinoma.

BEYOND: A Randomized, Double-Blind, Placebo-Controlled, Multicenter, Phase III Study of First-Line Carboplatin/Paclitaxel Plus Bevacizumab or Placebo in Chinese Patients With Advanced or Recurrent Nonsquamous Non–Small-Cell Lung Cancer

PURPOSE The phase III BEYOND trial was undertaken to confirm in a Chinese patient population the efficacy seen with first-line bevacizumab plus platinum doublet chemotherapy in globally conducted studies. PATIENTS AND METHODS Patients age ≥ 18 years with locally advanced, metastatic, or recurrent advanced nonsquamous non-small-cell lung cancer (NSCLC) were randomly assigned to receive carboplatin (area under the curve, 6) intravenously and paclitaxel (175 mg/m(2)) intravenously (CP) on day 1 of each 3-week cycle, for ≤ six cycles, plus placebo (Pl+CP) or bevacizumab (B+CP) 15 mg/kg intravenously, on day 1 of each cycle, until progression, unacceptable toxicity, or death. The primary end point was progression-free survival (PFS); secondary end points were objective response rate, overall survival, exploratory biomarkers, safety. RESULTS A total of 276 patients were randomly assigned, 138 to each arm. PFS was prolonged with B+CP versus Pl+CP (median, 9.2 v 6.5 months, respectively; hazard ratio [HR], 0.40; 95% CI, 0.29 to 0.54; P < .001). Objective response rate was improved with B+CP compared with Pl+CP (54% v 26%, respectively). Overall survival was also prolonged with B+CP compared with Pl+CP (median, 24.3 v 17.7 months, respectively; HR, 0.68; 95% CI, 0.50 to 0.93; P = .0154). Median PFS was 12.4 months with B+CP and 7.9 months with Pl+CP (HR, 0.27; 95% CI, 0.12 to 0.63) in EGFR mutation-positive tumors and 8.3 and 5.6 months, respectively (HR, 0.33; 95% CI, 0.21 to 0.53), in wild-type tumors. Safety was similar to previous studies of B+CP in NSCLC; no new safety signals were observed. CONCLUSION The addition to bevacizumab to carboplatin/paclitaxel was well tolerated and resulted in a clinically meaningful treatment benefit in Chinese patients with advanced nonsquamous NSCLC.

A gene therapy for cancer based on the angiogenesis inhibitor, vasostatin

The growth and persistence of solid tumors and their metastasis are angiogenesis-dependent. Vasostatin, the N-terminal domain of calreticulin inclusive of amino acids 1–180, is a potent angiogenesis inhibitor. To investigate whether intramuscular administration of vasostatin gene has the antitumor activity in mouse tumor models, we constructed a plasmid DNA encoding vasostatin and a control vector. Production and secretion of vasostatin protein by COS cells transfected with the plasmid DNA encoding vasostatin (pSecTag2B-vaso) were confirmed by Western blot analysis and ELISA. Conditioned medium from vasostatin-transfected COS cells apparently inhibited human umbilical vein endothelial cell (HUVEC) and mouse endothelial cell (SVEC4-10) proliferation, compared with conditioned medium from the COS cells transfected with control vector or non-transfected cells. Treatment with pSecTag2B-vaso twice weekly for 4 weeks resulted in the inhibition of tumor growth and the prolongation of the survival of tumor-bearing mice. The sustained high level of vasostatin protein in serum could be identified in ELISA. Angiogenesis was apparently inhibited in tumor by immunohistochemical analysis. Angiogenesis was also inhibited in the chicken embryo CAM assay and mouse corneal micropocket assay. The increased apoptotic cells were found within the tumor tissues from the mice treated with plasmid DNA encoding vasostatin. Taken together, the data in the present study indicate that the cancer gene therapy by the intramuscular delivery of plasmid DNA encoding vasostatin, is effective in the inhibition of the systemic angiogenesis and tumor growth in murine models. The present findings also provide further evidence of the anti-tumor effects of the vasostatin, and may be of importance for the further exploration of the application of this molecule in the treatment of cancer.

Immunogene Therapy of Tumors with Vaccine Based on Xenogeneic Epidermal Growth Factor Receptor

The breaking of immune tolerance against self epidermal growth factor receptor (EGFr) should be a useful approach for the treatment of receptor-positive tumors with active immunization. To test this concept, we constructed a plasmid DNA encoding extracellular domain of xenogeneic (human) EGFr (hEe-p) or corresponding control mouse EGFr (mEe-p) and empty vector (c-p). Mice immunized with hEe-p showed both protective and therapeutic antitumor activity against EGFr-positive tumor. Sera isolated from the hEe-p-immunized mice exhibited positive staining for EGFr-positive tumor cells in flow cytometric analysis and recognized a single 170-kDa band in Western blot analysis. Ig subclasses responded to rEGFr proteins were elevated in IgG1, Ig2a, and Ig2b. There was the deposition of IgG on the tumor cells. Adoptive transfer of the purified Igs showed the antitumor activity. The increased killing activity of CTL against EGFr-positive tumor cells could be blocked by anti-CD8 or anti-MHC class I mAb. In vivo depletion of CD4+ T lymphocytes could completely abrogate the antitumor activity, whereas the depletion of CD8+ cells showed partial abrogation. The adoptive transfer of CD4-depleted (CD8+) or CD8-depleted (CD4+) T lymphocytes isolated from mice immunized with hEe-p vaccine showed the antitumor activity. In addition, the increase in level of both IFN-γ and IL-4 was found. Taken together, these findings may provide a new vaccine strategy for the treatment of EGFr-positive tumors through the induction of the autoimmune response against EGFr in a cross-reaction between the xenogeneic homologous and self EGFr.

Primary Tumor Standardized Uptake Value Measured on F18-Fluorodeoxyglucose Positron Emission Tomography Is of Prediction Value for Survival and Local Control in Non–Small-Cell Lung Cancer Receiving Radiotherapy: Meta-Analysis

Introduction: The 2-[18F]-Fluorodeoxyglucose (FDG) positron emission tomography (PET/CT) has become an imaging tool for clinical assessment of tumor, node, metastasis in non–small-cell lung cancer (NSCLC). Primary tumor maximum standardized uptake value (SUVmax) on 18F-FDG PET/CT before and after radiation therapy (RT) has been studied as a potential prognostic factor for NSCLC patients receiving radiotherapy. However, the sample sizes of most studies were small, and the results of the prediction value of SUVmax remained undetermined, which lead us to perform a meta-analysis to improve the precision in estimating its effect. Methods: We performed a meta-analysis of published literature for primary tumor SUVmax-based biomarkers of the outcome of NSCLC receiving radiotherapy. The required data for estimation of individual hazard ratios (HRs) to compare patients with a low and a high SUVmax were extracted from each publication. A combined HR was calculated by Stata statistical software (Version 11). All of the results were verified by two persons to ensure its accuracy. Results: Thirteen studies were finally included into this meta-analysis; data are available in 13 studies for pre-RT primary tumor SUVmax and in five studies for post-RT. For overall survival, the combined HR estimate was 1.05 (95% confidence interval [CI], 1.02–1.08) and 1.32 (95% CI, 1.15–1.51) for pre-RT SUVmax and post-RT SUVmax, respectively; 1.26 (95% CI, 1.05–1.52) and 2.01 (95% CI, 1.16–3.46) for local control (LC). In stereotactic body radiotherapy (SBRT) group, HR for LC was 1.11 (95% CI, 1.06–1.18) and 2.19 (95% CI, 1.34–3.60) for pre-SBRT SUVmax and post-SBRT SUVmax, respectively. Conclusion: Both pre-RT and post-RT primary tumor SUVmax can predict the outcome of patients with NSCLC treated with radiotherapy. Patients with high levels of pre-RT SUVmax seemed to have poorer overall survival and LC.

Dose-individualized stereotactic body radiotherapy for T1-3N0 non-small cell lung cancer: long-term results and efficacy of adjuvant chemotherapy.

PURPOSE To evaluate the efficacy of dose-individualized stereotactic body radiotherapy (SBRT) and adjuvant chemotherapy in stage T1-3N0M0 non-small cell lung cancer (NSCLC). MATERIALS AND METHODS Sixty-five patients with T1-3N0M0 NSCLC treated by SBRT between April 2001 and August 2005 were included. Twenty patients were CT-staged at stage T1, 34 at stage T2, and 11 at stage T3. All patients underwent no elective nodal irradiation. SBRT total doses ranged from 71.8 to 115.2Gy of biological equivalent dose (BED) in 3.6 to 8.0Gy daily fractions. Seventeen patients were offered cisplatin-containing adjuvant chemotherapy. RESULTS The overall response rate was 90.6% at six months. The 3- and 5-year overall survival rates for all patients were 57.3% and 35.1%, respectively, and for stage T1-2 patients these were 60.2, 36.5%, respectively. Of all patients, the 3- and 5-year overall survival rates of adjuvant chemotherapy group were 80.5% and 46.0%, respectively, and those of patients with SBRT alone were 49.6% and 31.5%, respectively. Patients who accepted adjuvant chemotherapy had a lower relapse rate and better overall survival. Acute toxicities were mild, and no long-term toxicity was observed. CONCLUSIONS Patients treated with the dose-individualization strategy of SBRT showed excellent local control and improved survival. Adjuvant chemotherapy may reduce the frequency of relapse and increase overall survival in stage at T1-3N0M0 NSCLC patients.