Clinical outcomes of active specific immunotherapy in advanced colorectal cancer and suspected minimal residual colorectal cancer: a meta-analysis and system review

Vaccine Therapies for Cancer: Then and Now

There are strong biologic and preclinical rationales for the development of therapeutic cancer vaccines; however, the clinical translation of this treatment strategy has been challenging. It is now understood that many previous clinical trials of cancer vaccines used target antigens or vaccine designs that inherently lacked sufficient immunogenicity to induce clinical responses. Despite the historical track record, breakthrough advances in cancer immunobiology and vaccine technologies have supported continued interest in therapeutic cancer vaccinations, with the hope that next-generation vaccine strategies will enable patients with cancer to develop long-lasting anti-tumor immunity. There has been substantial progress identifying antigens and vaccine vectors that lead to strong and broad T cell responses, tailoring vaccine designs to achieve optimal antigen presentation, and finding combination partners employing complementary mechanisms of action (e.g., checkpoint inhibitors) to overcome the diverse methods cancer cells use to evade and suppress the immune system. Results from randomized, phase 3 studies testing therapeutic cancer vaccines based on these advances are eagerly awaited. Here, we summarize the successes and failures in the clinical development of cancer vaccines, address how this historical experience and advances in science and technology have shaped efforts to improve vaccines, and offer a clinical perspective on the future role of vaccine therapies for cancer.

Stimulation of DC-CIK with PADI4 Protein Can Significantly Elevate the Therapeutic Efficiency in Esophageal Cancer

Background

PADI4 has extensive expression in many tumors. This study applied PADI4 as a tumor marker to stimulate DC- (dendritic cell-) CIK (cytokine-induced killer), an immunotherapy approach.

Methods

A PADI4 expression plasmid was transfected into EC-originating ECA-109 cells. PADI4 gene was also inserted into a prokaryotic expression vector to produce recombinant protein. Lysate from PADI4-overexpressing cells or the purified recombinant PADI4 protein was used to load DCs, and the cells were then coincubated with CIK cells. DC and CIK cell phenotypes were determined using flow cytometry. The proliferation and viability of CIK cells were analyzed using trypan blue staining. The cytotoxic effect of DC-CIK cells on cultured ECA-109 cells was determined using CCK8 assays. Tumor-bearing mice were prepared by injection of ECA-109 cells. DC-CIK cells stimulated with lysate from PADI4-overexpressing cells or the PADI4 recombinant protein were injected into the tumor-bearing mice. The tumor growth was measured with magnetic resonance imaging (MRI).

Results

Following incubation with lysate from PADI4-overexpressing cells, the ratio of CD40⁺ DCs increased by 17.5%. Induction of CIK cells with PADI4-stimulated DCs elevated the cell proliferation by 53.2% and the ability of CIK cells to kill ECA-109 cells by 12.1%. DC-CIK cells stimulated with lysate from PADI4-overexpressing cells suppressed tumor volume by 18.6% in the tumor-bearing mice. The recombinant PADI4 protein showed a similar effect on CIK cell proliferation and cytotoxicity as that of the lysate from PADI4-overexpressing cells. Furthermore, the recombinant protein elevated the ratio of CD40⁺ DCs by 111.8%, CD80⁺ DCs by 6.3%, CD83⁺ DCs by 30.8%, and CD86⁺ DCs by 7.8%. Induction of CIK cells with rPADI4-stimulated DCs elevated the cell proliferation by 50.3% and the ability of CIK cells to kill ECA-109 cells by 14.7% and suppressed tumor volume by 35.1% in the animal model.

Conclusion

This study demonstrates that stimulation of DC-CIK cells with PADI4 significantly suppressed tumor growth in tumor-bearing mice by promoting DC maturation, CIK cell proliferation, and cytotoxicity. PADI4 may be a potential tumor marker that could be used to improve the therapeutic efficiency of DC-CIK cells.

Immunotherapy of colorectal cancer: new perspectives after a long path

Although significant therapeutic improvement has been achieved in the last 10 years, the survival of metastatic colorectal cancer patients remains in a range of 28 to 30 months. Presently, systemic treatment includes combination chemotherapy with oxaliplatin and/or irinotecan together with a backbone of 5-fluorouracil/levofolinate, alone or in combination with monoclonal antibodies to VEGFA (bevacizumab) or EGF receptor (cetuximab and panitumumab). The recent rise of immune checkpoint inhibitors in the therapeutic scenario has renewed scientific interest in the investigation of immunotherapy in metastatic colorectal cancer patients. According to our experience and view, here, we review the immunological strategies investigated for the treatment of this disease, including the use of tumor target-specific cancer vaccines, chemo-immunotherapy and immune checkpoint inhibitors.

Adaptive T cell responses induced by oncolytic Herpes Simplex Virus-granulocyte macrophage-colony-stimulating factor therapy expanded by dendritic cell and cytokine-induced killer cell adoptive therapy

Purpose: Although local oncolytic viral therapy (OVT) may enhance tumor lysis, antigen release, and adaptive immune responses, systemic antitumor responses post-therapy are limited. Adoptive immunotherapy with autologous dendritic cells (DC) and cytokine-induced killer cells (DC-CIK) synergizes with systemic therapies. We hypothesized that OVT with Herpes Simplex Virus-granulocyte macrophage-colony-stimulating factor (HSV-GM-CSF) would induce adaptive T cell responses that could be expanded systemically with sequential DC-CIK therapy. Patients and Methods: We performed a pilot study of intratumoral HSV-GM-CSF OVT followed by autologous DC-CIK cell therapy. In addition to safety and clinical endpoints, we monitored adaptive T cell responses by quantifying T cell receptor (TCR) populations in pre-oncolytic therapy, post-oncolytic therapy, and after DC-CIK therapy. Results: Nine patients with advanced malignancy were treated with OVT (OrienX010), of whom seven experienced stable disease (SD). Five of the OVT treated patients underwent leukapheresis, generation, and delivery of DC-CIKs, and two had SD, whereas three progressed. T cell receptor sequencing of TCR β sequences one month after OVT therapy demonstrates a dynamic TCR repertoire in response to OVT therapy in the majority of patients with the systematic expansion of multiple T cell clone populations following DC-CIK therapy. This treatment was well tolerated and long-term event free and overall survival was observed in six of the nine patients. Conclusions: Strategies inducing the local activation of tumor-specific immune responses can be combined with adoptive cellular therapies to expand the adaptive T cell responses systemically and further studies are warranted.

Cancer vaccines in colon and rectal cancer over the last decade: lessons learned and future directions

INTRODUCTION

Great advances have been made in screening for and treatment of colorectal cancer (CRC), but recurrence rates remain high and additional therapies are needed. There is great excitement around the field of immunotherapy and many attempts have been made to bring immunotherapy to CRC through a cancer vaccine. Areas covered: This is a detailed review of the last decade's significant CRC vaccine trials. Expert commentary: Monotherapy with a CRC vaccine is likely best suited for adjuvant therapy in disease free patients. Vaccine therapy elicits crucial tumor infiltrating lymphocytes, which are lacking in microsatellite-stable tumors, and therefore may be better suited for these patients. The combination of CRC vaccines with checkpoint inhibitors may unlock the potential of immunotherapy for a much broader range of patients. Future studies should focus on vaccine monotherapy in correctly selected patients and combination therapy in more advanced disease.

Phase I clinical trial of a five-peptide cancer vaccine combined with cyclophosphamide in advanced solid tumors

We designed a phase I trial to investigate the safety, immune responses and clinical benefits of a five-peptide cancer vaccine in combination with chemotherapy. Study subjects were patients positive for HLA-A2402 with locally advanced, metastatic, and/or recurrent gastrointestinal, lung or cervical cancer. Eighteen patients including nine cases of colorectal cancer were treated with escalating doses of cyclophosphamide 4days before vaccination. Five HLA-A2402-restricted, tumor-associated antigen (TAA) epitope peptides from KOC1, TTK, URLC10, DEPDC1 and MPHOSPH1 were injected weekly for 4weeks. Treatment was well tolerated without any adverse events above grade 3. Analysis of peripheral blood lymphocytes showed that the number of regulatory T cells dropped from baseline after administration of cyclophosphamide and confirmed that TAA-specific T cell responses were associated significantly with longer overall survival. This phase I clinical trial demonstrated safety and promising immune responses that correlated with vaccine-induced T-cell responses. Therefore, this approach warrants further clinical studies.

Validity of combination active specific immunotherapy for colorectal cancer: a meta-analysis of 2993 patients

BACKGROUND AIMS

The aim of this study was to investigate whether active specific immunotherapy (ASI) is able to demonstrate therapeutic efficacy against colorectal cancer.

METHODS

We conducted a systematic review of published papers from MEDLINE, the Cochrane Central Register of Controlled Trials, EMBASE, the Wanfang Database, the China Science and Technology Periodical Database and China Journal Net. Published data were extracted independently by two authors who used predefined database templates. The effects of ASI were compared with those of surgery alone, and a pooled analysis was performed with the use of the data from random- or fixed-effect models.

RESULTS

Twelve trials matched our inclusion criteria (n = 2993, including 1842 control subjects). The overall analysis showed a significant survival benefit [1-, 2-, 3-, 4-, 5-, 6- and 7-year overall survival (OS), P < 0.05; 10-year OS, P < 0.001] in favor of ASI immunotherapy combined with surgery, but there was not an improvement in the 8- or 9-year OS (P > 0.05). The disease-free survival (DFS) rate was improved after the combination of ASI immunotherapy (2-, 3-, 5- and 10-year DFS, P < 0.05), but no significant improvement was noted for the 1-, 4-, 6-, 7-, 8- or 9-year DFS (P > 0.05). In addition, the disease-specific survival (DSS) was improved at some time points after the combination of ASI immunotherapy and surgery (2-, 3-, 4-, 5- and 6-year DSS, P < 0.05, but not the 1-, 7-, 8- or 9-year DSS, P > 0.05). An improved 2-, 3-, 4-, 5- and 6-year recurrence-free interval (RFI) (P < 0.05) was also observed in patients who received ASI therapy, but this was not observed for the 1-year RFI (P > 0.05). Furthermore, an analysis of the recurrence-free survival (RFS) showed that it was significantly increased in the ASI plus surgery group (1-, 2-, 3-, 4-, 5- and 6-year RFS, P < 0.001). The funnel plots showed that the analyses were relatively reliable and the publication bias was small.

CONCLUSIONS

The combination of ASI immunotherapy and surgery was superior in prolonging the overall survival time and enhancing the recurrence-free survival rate compared with surgery alone.

Designing effective vaccines for colorectal cancer

Achieving long-term control of colorectal cancers with therapeutic vaccines that generate potent anti-tumor T cell and antibody responses has been a goal for more than two decades. To date, clinical trials of these vaccines have demonstrated induction of immune responses, but clinical benefit has been limited. Improved vector delivery systems with enhanced immunostimulatory properties, decreased immunogenicity against vector and improved antigen presentation are some of the key features of modern tumor vaccines. Furthermore, an improved understanding of the various immunosuppressive factors in the tumor microenvironment and regional lymph nodes, coupled with a burgeoning ability to impair inhibitory immune synapses, highlights a growing opportunity to induce beneficial antigen-specific responses against tumor. The combination of improved antigenic delivery systems, coupled with therapeutic immune activation, represents state-of-the-art colorectal vaccine design concepts with the goal of augmenting immune responses against tumor and improving clinical outcomes.

Effectiveness and safety of chemotherapy combined with dendritic cells co-cultured with cytokine-induced killer cells in the treatment of advanced non-small-cell lung cancer: a systematic review and meta-analysis

Background

Lung cancer, particularly non-small-cell lung cancer (NSCLC) is the leading cause of cancer mortality. Chemotherapy combined dendritic cells co-cultured with cytokine-induced killer cells (DC-CIK) immunotherapy has been applied in advanced NSCLC patients' treatment, but couldn't provide consistent beneficial results. Therefore, it is necessary to evaluate the efficiency and safety of combination therapy to promote the application.

Methods

A literature search for randomized controlled trials of NSCLC was conducted in PubMed database. Before meta-analysis was performed, studies were evaluated heterogeneity. Pooled risk ratios (RRs) were estimated and 95% confidence intervals (CIs) were calculated using a fixed-effect model. Sensitivity analysis was also performed.

Results

Six eligible trials were enrolled. Efficiency and safety of chemotherapy followed by DC-CIK immunotherapy (experimental group) and chemotherapy alone (control group) were compared. 1-year overall survival (OS) (P = 0.02) and progression free survival (PFS) (P = 0.005) in the experimental group were significantly increased compared with the control. Disease control rate (DCR) (P = 0.006) rose significantly in experimental group. However, no significant differences between the two groups were observed in 2-year OS (P = 0.21), 2-year PFS (P = 0.10), overall response rate (ORR) (P = 0.76) and partial response (PR) (P = 0.22). Temporary fever, anemia, leukopenia and nausea were the four major adverse events (AEs) treated by chemotherapy. The incidence of anemia, leukopenia and nausea in the experimental group was obviously lower than the control group. Temporary fever rate was higher in experimental group than that in the control, but could be alleviated by taking sufficient rest.

Conclusions

Chemotherapy combined with DC-CIK immunotherapy showed superiority in DCR, 1-year OS and PFS, and no more AEs appeared, however, there was no significant improvement in ORR, PR, 2-year OS and PFS. As a whole, the combination therapy is safer but modest in efficacy for advanced NSCLC patients.

Retrospective comparative study of the effects of dendritic cell vaccine and cytokine-induced killer cell immunotherapy with that of chemotherapy alone and in combination for colorectal cancer

Purpose. This retrospective study determined the delayed-type hypersensitivity (DTH) skin test and safety of dendritic cell (DC) vaccine and cytokine-induced killer (CIK) cell immunotherapy and the survival compared to chemotherapy in 239 colorectal cancer (CRC) patients. Methods. DTH and safety of the immunotherapy were recorded. The overall survival (OS) and disease free survival curves were compared according to the immunotherapy and/or chemotherapy received with Kaplan-Meier estimates. Results. Of the 70 patients who received immunotherapy, 62.86% had a positive DTH skin test, 38.57% developed fever, 47.14% developed insomnia, 38.57% developed anorexia, 4.29% developed joint soreness, and 11.43% developed skin rash. For 204 resectable CRC patients, median survival time (MST) (198.00 days) was significantly longer in patients with immunotherapy plus chemotherapy than with chemotherapy alone (106.00 days) (P = 0.02). For 35 patients with unresectable or postsurgery relapsed CRC and who were confirmed to be dead, no statistical difference was observed in the MST between the patients treated with immunotherapy and with chemotherapy (P = 0.41). MST in the patients treated with chemotherapy plus immunotherapy was 154 days longer than that of patients treated with chemotherapy alone (P = 0.41). Conclusions. DC vaccination and CIK immunotherapy did not cause severe adverse effects, induce immune response against CRC, and prolong OS.

Toward a drug development path that targets metastatic progression in osteosarcoma

Despite successful primary tumor treatment, the development of pulmonary metastasis continues to be the most common cause of mortality in patients with osteosarcoma. A conventional drug development path requiring drugs to induce regression of established lesions has not led to improvements for patients with osteosarcoma in more than 30 years. On the basis of our growing understanding of metastasis biology, it is now reasonable and essential that we focus on developing therapeutics that target metastatic progression. To advance this agenda, a meeting of key opinion leaders and experts in the metastasis and osteosarcoma communities was convened in Bethesda, Maryland. The goal of this meeting was to provide a "Perspective" that would establish a preclinical translational path that could support the early evaluation of potential therapeutic agents that uniquely target the metastatic phenotype. Although focused on osteosarcoma, the need for this perspective is shared among many cancer types. The consensus achieved from the meeting included the following: the biology of metastatic progression is associated with metastasis-specific targets/processes that may not influence grossly detectable lesions; targeting of metastasis-specific processes is feasible; rigorous preclinical data are needed to support translation of metastasis-specific agents into human trials where regression of measurable disease is not an expected outcome; preclinical data should include an understanding of mechanism of action, validation of pharmacodynamic markers of effective exposure and response, the use of several murine models of effectiveness, and where feasible the inclusion of the dog with naturally occurring osteosarcoma to define the activity of new drugs in the micrometastatic disease setting.

Tumor radiation therapy creates therapeutic vaccine responses to the colorectal cancer antigen GUCY2C

PURPOSE

Radiation therapy (RT) is thought to produce clinical responses in cancer patients, not only through direct toxicity to cancer cells and supporting tumor stroma cells, but also through activation of immunologic effectors. More recently, RT has potentiated the local and systemic effects of cancer immunotherapy (IT). However, combination regimens that maximize immunologic and clinical efficacy remain undefined.

METHODS AND MATERIALS

We evaluated the impact of local RT on adenoviral-mediated vaccination against the colorectal cancer antigen GUCY2C (Ad5-GUCY2C) in a murine subcutaneous tumor model using mouse CT26 colon cancer cells (CT26-GUCY2C). Immune responses were assessed by ELISpot, and clinical responses were assessed by tumor size and incidence.

RESULTS

The specific sequence of tumor-directed RT preceding Ad5-GUCY2C IT transformed inactive therapeutic Ad5-GUCY2C vaccination into a curative vaccine. GUCY2C-specific T cell responses were amplified (P<.05), tumor eradication was maximized (P<.01), and tumor volumes were minimized (P<.001) in mice whose tumors were irradiated before, compared with after, Ad5-GUCY2C vaccination. The immunologic and antitumor efficacy of Ad5-GUCY2C was amplified comparably by unfractionated (8 Gy × 1), or biologically equivalent doses of fractionated (3.5 Gy × 3), RT. The antitumor effects of sequential RT and IT (RT-IT) depended on expression of GUCY2C by tumor cells and the adenoviral vaccine vector, and tumor volumes were inversely related to the magnitude of GUCY2C-specific T cell responses. Moreover, mice cured of CT26-GUCY2C tumors by RT-IT showed long-lasting antigen-dependent protection, resisting tumors formed by GUCY2C-expressing 4T1 breast cancer cells inoculated 50 days after CT26 cells.

CONCLUSIONS

Optimal sequencing of RT and IT amplifies antigen-specific local and systemic immune responses, revealing novel acute and long-term therapeutic antitumor protection. These observations underscore the importance of modality sequence optimization before the initiation of clinical trials of RT and IT to maximize immune and antitumor responses.

Efficacy of ex vivo activated and expanded natural killer cells and T lymphocytes for colorectal cancer patients

Immune cell-based therapies using natural killer (NK) cells and cytotoxic T cells are under constant scrutiny, with the aim to design an effective and reduced-toxicity therapy, which will benefit patients via improved quality of life and improved prognosis. Four patients with stage IV colon cancer were administered 1, 3, 5 and 6 effector cell intravenous infusions, respectively. Peripheral blood was collected from the patients and the ex vivo activation and expansion of NK and T cells was performed in Good Manufacturing Practice-certified clean rooms for ~12-15 days. Immunophenotypic analysis of the peripheral blood mononuclear cells (PBMCs) and expanded NK and T cells was conducted using flow cytometry and the patients were followed up. On average, 4.8×10⁷ initial PBMCs and 2.7×10⁹ total expanded cells were obtained. The intravenous infusions of the expanded cells were not accompanied by adverse reactions. Improved prognosis, reflected by a considerable decrease in the cancer markers, accompanied by an improved quality of life in the patients were observed. In conclusion, potential strategies are currently under development for the large-scale production of effectors cells; therefore, autologous immune enhancement therapy (AIET) may be considered as a viable approach to cancer treatment.

The prognostic impact of human leukocyte antigen (HLA) class I antigen abnormalities in salivary gland cancer. A clinicopathological study of 288 cases

AIMS

To study abnormalities of proteins of the major histocompatibility complex class I in a series of 288 salivary gland carcinomas, and to correlate findings with patients' overall survival (OS).

METHODS AND RESULTS

Protein expression of human leukocyte antigen (HLA)-A, heavy chain (HC)-10, β2 -microglobulin, low molecular weight polypeptides (LMP) 2 and 7, transporters associated with antigen processing (TAP) 1 and 2, calnexin, calreticulin, endoplasmic reticulum (ER) p57 and tapasin was evaluated by immunohistochemistry and semiquantitatively analyzed. As compared with normal salivary gland tissue, HLA-A, LMP7, TAP2 and HLA class I were significantly down-regulated in salivary gland carcinomas, whereas β2 -microglobulin, calnexin, LMP2, and TAP1 were upregulated. Expression of calreticulin, ERp57 and tapasin was unaltered. In univariate Kaplan-Meier analyses, low expression of LMP7 (P = 0.005) and high expression of β2 -microglobulin (P = 0.028), HLA-A (P < 0.001), TAP1 (P = 0.01), and tapasin (P < 0.001) were significantly associated with shorter OS. In multivariate analysis incorporating tumour stage, nodal/distant metastasis, and grade, HLA-A (P = 0.014), LMP7 (P = 0.033), and tapasin (P = 0.024), as well as distant metastasis (P = 0.012) and high tumour grade (P < 0.001), remained statistically significant.

CONCLUSION

The prognostic influence of up-regulated HLA-A and tapasin and down-regulated LMP7 may provide a rationale for targeting these specific components of the antigen processing and presentation pathway in salivary gland carcinomas.

[Immunotherapy for colorectal cancer]

Recent studies have underlined the close link between immune response and prognosis of patients with colorectal cancer (CRC). Immune response understanding combined with biotechnology progress of the last years has allowed development of immunotherapy strategies in CRC. Immunotherapy strategies are divided in "active" or "passive" strategies (patients immune system stimulation or not) and considering the activation of antigen specific immune response or not. These immunotherapy strategies are well tolerated and induced cellular and humoral response correlated with clinical response. Many monoclonal antibodies targeting signalisation pathways or angiogenic growth factors have demonstrated their efficacy in CRC. Multiple vaccine strategies, using different tumour associated antigens, have demonstrated a biological efficacy but with poor clinical results. Results are more promising in adjuvant setting but need to be confirmed by randomized trials. Adoptive immunotherapy with transfer of tumour associated antigen specific T cell is probably the most promising strategy. Actually, except monoclonal antibodies, immunotherapy is not used in clinical practice in CRC due to the lack of results and absence of standardisation.

Adjuvant therapy in patients with stage II and III colon cancer under 70 years of age

SUMMARY Colorectal cancer is a common malignancy and its prognosis has improved over recent decades due to sustained efforts of the scientific community. This review focuses on adjuvant therapy across the lifespan of patients under 70 years of age. Here, we discuss the standard management of patients with stage III colon cancer, consisting of fluoropyrimidines and oxaliplatin combination for 6 months. The specific issues faced by patients with stage II colon cancer, including adjuvant chemotherapy in high-risk patients, are discussed. Finally, we describe the distinctive characteristics of patients with colon cancer under 40 years of age and the prospects of adjuvant chemotherapy in patients with colon cancer.

New developments in castrate-resistant prostate cancer

Castrate-resistant prostate cancer (CRPC) occurs when disease progresses in the presence of castrate levels of androgens and remains sensitive to further hormonal manipulation. For many years the treatment of CRPC was limited to the use of docetaxel for metastatic disease. However, this has recently changed with the approval of several new agents. Sipuleucel-T, an immunotherapeutic vaccine, is now available in the US for patients with non-metastatic CRPC and abiraterone, an oral enzyme inhibitor of androgen biosynthesis, as well as cabazitaxel, a cytotoxic chemotherapeutic, have been approved for the treatment of metastatic CRPC. Also, denosumab, a subcutaneous antibody, is now an option for the treatment of patients with CRPC with bone metastases, in addition to zoledronic acid, an intravenous bisphosphonate. Further treatment advances for metastatic CRPC therapeutics are in late stage phase III development. These include therapies affecting the androgen receptor (MDV3100) as well as additional immune-based therapeutics, PROSTVAC and ipilimumab. A broad range of agents is also emerging under the term targeted therapies. The endothelin-A receptor antagonist zibotentan, the tyrosine kinase inhibitors dasatinib, sorafenib and cabozantinib, the anti-angiogenic agent aflibercept, and the clusterin inhibitor custirsen, are all currently being tested for efficacy in metastatic CRPC. The mechanism of action of these and other promising agents are discussed alongside current therapeutic options and their potential place in the treatment landscape for CRPC is considered.

Strengths and weaknesses of immunotherapy for advanced non-small-cell lung cancer: a meta-analysis of 12 randomized controlled trials

Background

Lung cancer is one of the leading causes of cancer death worldwide. Non-small-cell lung cancer (NSCLC) accounts for approximately 85% of all lung cancers. Immunotherapy has yielded no consistent benefit to date for those patients. Assessing the objective efficacy and safety of immunotherapy for advanced NSCLC patients will help to instruct the future development of immunotherapeutic drugs.

Methodology and Principal Findings

We performed a meta-analysis of 12 randomized controlled trials including 3134 patients (1570 patients in the immunotherapy group and 1564 patients in the control group) with histologically confirmed stage IIIA, IIIB, or IV NSCLC. The analysis was executed with efficacy end points regarding overall survival (OS), progression-free survival (PFS), complete response (CR), partial response (PR), and total effective rate. Overall unstratified OS, PFS, PR, and total effective rate were significantly improved in advanced NSCLC patients in the immunotherapy group (P = 0.0007, 0.0004, 0.002, 0.003, respectively), whereas CR was not improved (P = 0.97). Subgroup analysis showed that monoclonal antibody (mAb) immunotherapy significantly improved the PFS, PR, and total effective rate and showed a trend of improving OS of advanced NSCLC patients compared with the control group, with one kind of adverse event being significantly dominant. Compared with the control group, the vaccine subgroup showed no significant difference with regard to serious adverse events, whereas cytokine immunotherapy significantly induced three kinds of serious adverse events.

Conclusions

Immunotherapy works efficiently on advanced NSCLC patients. Of several immunotherapies, mAb therapy may be a potential immunotherapy for advanced NSCLC patients, and become a standard complementary therapeutic approach in the future if the issues concerning toxicity and allergenicity of mAbs have been overcome.

Granulocyte-macrophage stimulating factor (GM-CSF) increases circulating dendritic cells but does not abrogate suppression of adaptive cellular immunity in patients with metastatic colorectal cancer receiving chemotherapy

Background

Advanced cancer and chemotherapy are both associated with immune system suppression. We initiated a clinical trial in patients receiving chemotherapy for metastatic colorectal cancer to determine if administration of GM-CSF in this setting was immunostimulatory.

Methods

Between June, 2003 and January, 2007, 20 patients were enrolled in a clinical trial (NCT00257322) in which they received 500 ug GM-CSF daily for 4 days starting 24 hours after each chemotherapy cycle. There were no toxicities or adverse events reported. Blood was obtained before chemotherapy/GM-CSF administration and 24 hours following the final dose of GM-CSF and evaluated for circulating dendritic cells and adaptive immune cellular subsets by flow cytometry. Peripheral blood mononuclear cell (PBMC) expression of γ-interferon and T-bet transcription factor (Tbx21) by quantitative real-time PCR was performed as a measure of Th1 adaptive cellular immunity. Pre- and post-treatment (i.e., chemotherapy and GM-CSF) samples were evaluable for 16 patients, ranging from 1 to 5 cycles (median 3 cycles, 6 biologic sample time points). Dendritic cells were defined as lineage (-) and MHC class II high (+).

Results

73% of patients had significant increases in circulating dendritic cells of ~3x for the overall group (5.8% to 13.6%, p = 0.02) and ~5x excluding non-responders (3.2% to 14.5%, p < 0.001). This effect was sustained over multiple cycles for approximately half of the responders, but tachyphylaxis over subsequent chemotherapy cycles was noted for the remainder. Treatment also led to a significant reduction in the proportion of circulating regulatory T-cells (Treg; p = 0.0042). PBMC Tbx21 levels declined by 75% following each chemotherapy cycle despite administration of GM-CSF (p = 0.02). PBMC γ-interferon expression, however was unchanged.

Conclusions

This clinical trial confirms the suppressive effects of chemotherapy on Th1 cellular immunity in patients with metastatic colorectal cancer but demonstrates that mid-cycle administration of GM-CSF can significantly increase the proportion of circulating dendritic cells. As the role of dendritic cells in anti-tumor immunity becomes better defined, GM-CSF administration may provide a non-toxic intervention to augment this arm of the immune system for cancer patients receiving cytotoxic therapy.

Trial Registration

ClinicalTrials.gov: NCT00257322

CIGB-247: a VEGF-based therapeutic vaccine that reduces experimental and spontaneous lung metastasis of C57Bl/6 and BALB/c mouse tumors

CIGB-247 is a novel cancer therapeutic vaccine that uses a mutated form of human VEGF as antigen. Being metastatic disease the most dramatic factor of tumor biology affecting patient survival and cure, preclinical evaluation of the impact of CIGB-247 vaccination on experimental metastasis mouse models is highly relevant, and constitutes the focus of this work. CIGB-247 was administered in a weekly schedule known to effectively reduce primary tumor growth. The vaccine was tested in experimental and spontaneous metastasis models of colon (CT26), lung (3LL-D122) and breast (F3II) carcinomas growing in C57Bl/6 or BALB/c mice. Primary tumor growth parameters, metastatic counts, and/or animal survival were recorded. Histology and specific humoral and cellular responses to the vaccine were evaluated. As compared to control groups, CIGB-247 vaccination significantly reduced the number and size of metastatic tumor foci in lungs after intravenous inoculation of CT26 and 3LL-D122 tumor cells. Spontaneous lung dissemination from 3LL-D122 and F3II breast tumor cells implanted in the footpad, or subcutaneously, was also reduced by immunization with CIGB-247. The vaccine elicited in both mouse strains antibodies specific for human and murine VEGF that effectively blocked the interaction of VEGF with VEGF receptor 2. Differing from other experimental reports that describe the use of VEGF for active tumor immunotherapy, CIGB-247 elicited a specific cellular response, measured both by a DTH increment and the induction of spleen cells cytotoxic to syngeneic tumor cells producing murine VEGF. In summary our results reinforce the potential of CIGB-247 vaccination to reduce both tumor growth and the number and size of tumor metastasis in lungs, the latter both after direct inoculations of cells in the blood stream, or as part of primary tumor progression in immunocompetent mice.

Influence of viral hepatitis status on prognosis in patients undergoing hepatic resection for hepatocellular carcinoma: a meta-analysis of observational studies

Background

The influence of viral hepatitis status on prognosis in patients undergoing hepatic resection for hepatocellular carcinoma (HCC) remains a matter of debate. This study is a meta-analysis of the available evidence.

Methods

A literature search was performed to identify comparative studies reporting postoperative survival of HCC in different types of viral hepatitis. Pooled odds ratios (OR) and weighted mean differences (WMD with 95% confidence intervals (95% CI) were calculated using either the fixed effects model or random effects model.

Results

Twenty studies matched the selection criteria and reported on 4744 subjects, of whom 2008 in the HBV-positive (B-HCC) group, 2222 in the HCV-positive (C-HCC) group, and 514 in the hepatitis B- and C-negative (NBNC-HCC). Meta-analysis showed that patients with HBV or HCV infection had a worse 5-year disease-free survival when compared to patients with NBNC-HCC (respectively: OR: 0.39, 95% CI: 0.28 to 0.53, P < 0.001; WMD: 0.37, 95% CI: 0.22 to 0.64, P < 0.001). There was a tendency toward higher 5-year overall survival rates in the NBNC-HCC group compared to those in the other two groups, although these differences were not statistically significant. Both the 5-year overall survival and disease-free survival were not different among the B-HCC and C-HCC groups.

Conclusions

Patients with positive serology for hepatitis B or C undergoing resection for HCC had a poor prognosis compared to patients with negative serology.