Cd40 Activation as Potential Tool in Malignant Neoplasms

CD40 expression and its prognostic significance in human gastric carcinoma

This study aimed to detect the relationship between CD40 (protein and mRNA) expression and human gastric cancer and to determine the prognostic significance of CD40 in gastric cancer patients. We collected 128 cases of gastric cancer specimens, and the expression of CD40 (protein and mRNA) was measured by immunohistochemistry and in situ hybridization. Our study indicated that CD40 is constitutively expressed in human gastric carcinoma tissues. Positive expression of CD40 (protein and mRNA) in gastric cancer tissues was closely related to the tumor TNM stage and the presence of distant metastasis, with CD40 mRNA also being correlated with the presence of lymphatic metastasis. Furthermore, the expression of CD40 (protein and mRNA) is closely related to the prognosis of gastric cancer patients. The expression of CD40 protein and mRNA is positively correlated with the presence of distant (for both protein and mRNA) and lymphatic (for mRNA only) metastasis, and an increased tumor TNM stage in gastric carcinoma. Patients who express low levels of CD40 may have a better prognosis than those who have higher levels of CD40.

Potential role of soluble CD40 ligand as inflammatory biomarker in colorectal cancer patients

Platelet activation observed in cancer patients is associated with the release of various cytokines, including P-selectin and CD40 ligand (CD40L). We analyzed the plasma levels of sCD40L in association with adhesion molecules (sP-selectin and sVCAM-1) to check the hypothesis of a possible involvement in cancer progression.Blood samples were obtained from 59 patients with different stages of colorectal cancer (CRC) and 29 age and gender-matched control subjects. Plasma sCD40L, sP-selectin, and sVCAM-1 concentrations were measured with quantitative sandwich enzyme-linked immunoassay.All patients with CRC had significantly higher levels of sCD40L (p<0.001), sP-selectin (p<0.02), and sVCAM-1 (p<0.03), as compared to healthy subjects. The level of sCD40L significantly correlated with sP-selectin (p<0.05) in patients with distant metastases to the liver. We also observed a high negative correlation between sP-selectin and platelets count (p<0.02) in patients with lymph node metastasis. The receiver-operator curve for CRC patients indicated that the area under the curve for sCD40L was 0.915, which may indicate its high efficiency as an inflammatory marker.In our study, the sCD40L correlated with sP-selectin in patients with advanced stage of CRC, which might indicate its possible participation in metastasis formation.

Enhancement of Rituximab-induced cell death by the physical association of CD20 with CD40 molecules on the cell surface

CD20 is an attractive therapeutic target given the success of its monoclonal antibody, Rituximab, in the treatment of B-cell malignancies and B-cell-mediated autoimmune diseases. Treatment with Rituximab causes a rapid depletion of B cells and a decrease in disease symptoms. Despite the clinical efficiency of Rituximab, its mechanism of action is not completely understood. In this study, we aimed at further investigating the Rituximab-induced cell death and the factors affecting such responses. Our results indicate that Rituximab-induced cell death depends on the nature of the cells and levels of CD20 expression on the cell surface. Coexpression of CD20 with CD40, a member of the TNF receptor family that is known to be physically associated with CD20 on the cell surface, enhances the apoptotic response induced by Rituximab. Inhibiting the formation of CD40 disulfide-bound-homodimers, a process required for some CD40 signaling, further enhances Rituximab-induced cell death. Cell death induced by anti-CD40 mAb is also upregulated by the presence of CD20, suggesting a bidirectional influence of the CD20/CD40 association. Moreover, treating cells with both anti-CD20 and anti-CD40 antibodies improves the cell death response induced by a single-agent treatment. These results highlight the role of the CD20/CD40 association in triggering B-cell depletion and may pave the way for an alternative more efficient therapeutic strategy in treating B-cell-mediated disorders.

Desmoplasia in pancreatic cancer. Can we fight it?

The hallmark of pancreatic tumours, the desmoplastic reaction, provides a unique microenvironment that affects pancreatic tumour behaviour, its ability to grow and metastasize as well as resist the effects of chemotherapy. Complex molecular interactions and pathways give rise to the desmoplastic reaction. Breakdown or penetration of the desmoplastic reaction may hold the key to overcoming the limits of delivery of efficacious chemotherapy or the development of new targeted treatments. Herein we discuss such new developments to fight the desmoplastic reaction, including inhibitors of the epidermal growth factor, fibroblast growth factor, the hedgehog pathway, as well as new molecular targets like CD40 agonist and its effects on T cells, extracellular matrix modifying enzymes such as LOXL2 inhibitor and novel tumour penetrating peptides for delivery of drugs.

Serum concentrations and clinical significance of soluble CD40 ligand in patients with multiple myeloma

Multiple myeloma (MM) is a disease of plasma cells that express the CD40 receptor. Binding of the CD40 by its natural ligand, CD40 ligand (CD40L), produces growth arrest and/or apoptosis in MM. To evaluate serum levels of soluble CD40L (sCD40L) in MM patients and to correlate them with markers of disease activity and angiogenesis, such as vascular endothelial growth factor (VEGF), hepatocyte growth factor (HGF), interleukin-6 (IL-6), proliferation marker Ki-67 proliferation index (Ki-67 PI) and bone marrow plasma cell infiltration, fifty-eight MM patients were studied in diagnosis and 43 of them after completion of treatment. Serum levels of sCD40L, VEGF, HGF and IL-6 were measured by ELISA, whereas Ki-67 PI and bone marrow plasma cell infiltration were measured by immunohistochemistry. Pre-treatment levels of sCD40L in MM patients were higher compared to controls and to their levels after effective treatment. Treatment regimen did not affect the degree of reduction of sCD40L levels, whereas patient in partial remission had increased levels compared to those with better response. Significant differences were found among disease stages. There were also positive correlations between CD40L with HGF, VEGF, IL-6 and Ki-67 PI. Elevated serum sCD40L is found in patients with advanced MM stage and can be reduced after effective treatment. Increased levels of this mediator are correlated with angiogenic cytokines, providing evidences that CD40L/CD40 interactions play a significant role in the mechanisms of angiogenesis in MM patients.

Fc-engineered anti-CD40 antibody enhances multiple effector functions and exhibits potent in vitro and in vivo antitumor activity against hematologic malignancies

CD40 is highly expressed on various B-lineage malignancies and represents an attractive immunotherapy target for neoplastic disease. Previous work showed that engineering the Fc domain of an antibody for increased binding to Fcγ receptors (FcγRs) significantly enhanced Fc-mediated immune effector function and antitumor activity in vitro and in vivo. We developed a humanized anti-CD40 antibody similarly Fc-engineered for increased FcγR binding (XmAbCD40) and compared its efficacy with that of an anti-CD40 native IgG1 analog and the anti-CD20 antibody rituximab. XmAbCD40 increased antibody-dependent cell-mediated cytotoxicity (ADCC) up to 150-fold relative to anti-CD40 IgG1 against B-lymphoma, leukemia, and multiple myeloma cell lines, and significantly enhanced ADCC against primary tumors. XmAbCD40 was also superior to rituximab in enhancing ADCC (both in cell lines and primary tumors) and in augmenting antibody-dependent cellular phagocytosis. XmAbCD40 significantly inhibited lymphoma growth in disseminated and established mouse xenografts and was more effective than the IgG1 analog or rituximab. An anti-CD40 antibody constructed to abrogate FcγR binding showed no reduction of tumor growth, indicating that the in vivo antitumor activity of XmAbCD40 is primarily mediated via FcγR-dependent mechanisms. These data demonstrate that XmAbCD40 displays potent antitumor efficacy and merits further evaluation for the treatment of CD40(+) malignancies.

Chemomodulation of human dendritic cell function by antineoplastic agents in low noncytotoxic concentrations

The dose-delivery schedule of conventional chemotherapy, which determines its efficacy and toxicity, is based on the maximum tolerated dose. This strategy has lead to cure and disease control in a significant number of patients but is associated with significant short-term and long-term toxicity. Recent data demonstrate that moderately low-dose chemotherapy may be efficiently combined with immunotherapy, particularly with dendritic cell (DC) vaccines, to improve the overall therapeutic efficacy. However, the direct effects of low and ultra-low concentrations on DCs are still unknown. Here we characterized the effects of low noncytotoxic concentrations of different classes of chemotherapeutic agents on human DCs in vitro. DCs treated with antimicrotubule agents vincristine, vinblastine, and paclitaxel or with antimetabolites 5-aza-2-deoxycytidine and methotrexate, showed increased expression of CD83 and CD40 molecules. Expression of CD80 on DCs was also stimulated by vinblastine, paclitaxel, azacytidine, methotrexate, and mitomycin C used in low nontoxic concentrations. Furthermore, 5-aza-2-deoxycytidine, methotrexate, and mitomycin C increased the ability of human DCs to stimulate proliferation of allogeneic T lymphocytes. Thus, our data demonstrate for the first time that in low noncytotoxic concentrations chemotherapeutic agents do not induce apoptosis of DCs, but directly enhance DC maturation and function. This suggests that modulation of human DCs by noncytotoxic concentrations of antineoplastic drugs, i.e. chemomodulation, might represent a novel approach for up-regulation of functional activity of resident DCs in the tumor microenvironment or improving the efficacy of DCs prepared ex vivo for subsequent vaccinations.

Cationic liposome-mediated transfection of CD40 ligand gene inhibits hepatic tumor growth of hepatocellular carcinoma in mice

OBJECTIVE

To evaluate the efficacy of cationic liposome-mediated CD40 ligand (CD40L) gene therapy for hepatocellular carcinoma.

METHODS

1x10(6) of parental H22 cells or H22 cells transfected with the expression vector containing murine CD40L cDNA encoding the entire coding region (pcDNA3.1(+)-mCD40L) were inoculated subcutaneously into the left flanks of syngenic BALB/C mice. The tumor-bearing mice (tumor nodules 10 mm in maximal diameter) received the treatment of the intratumoral injection of pcDNA3.1(+)-mCD40L/Transfectam, pcDNA3.1(+), or phosphate-buffered saline (PBS), or no treatment. The mice were monitored for tumor growth weekly. We examined mCD40L messenger ribonucleic acid (mRNA) expression by reverse transcription polymerase chain reaction (RT-PCR) and the histologic changes in tumors at two weeks after intratumoral injection using immunohistochemical staining of tumor tissues.

RESULTS

All mice inoculated with parental H22 cells developed a tumor subcutaneously, and the tumor size increased progressively within three weeks. However, the mice receiving H22-CD40L cells exhibited complete regression of the tumor two weeks after tumor cell inoculation. The tumor-bearing animals with the treatment of pcDNA3.1(+) or PBS, or without treatment had progressive tumor growth, while those mice treated with pcDNA3.1(+)-mCD40L exhibited a significant inhibition of tumor growth. RT-PCR analysis showed that 783-bp fragments corresponding to the mCD40L mRNA were amplified only from pcDNA3.1(+)-mCD40L treated tumors. The tumor samples from pcDNA3.1(+)-mCD40L-treated mice showed significant lymphocyte infiltration, apoptotic bodies, and confluent necrosis in the tumor tissues.

CONCLUSION

The tumorigenicity of CD40L-expressing cells was abrogated when the cells were implanted subcutaneously. In vivo gene therapy of established liver tumor nodules in mice by the intratumoral injection of pcDNA3.1(+)-mCD40L led to significant tumor inhibition. There was mCD40L mRNA expression in the tissues from pcDNA3.1(+)-mCD40L-treated tumors. The intratumoral injection of pcDNA3.1(+)-mCD40L induced a strong inflammatory, mainly lymphocytic infiltration of the tumor, and increased the necrotic rate of the neoplastic cells.

Increase in CD30 ligand/CD153 and TNF-alpha expressing mast cells in basal cell carcinoma

Mast cells are a significant source of tumor necrosis factor (TNF) superfamily members, such as TNF-alpha, CD30 ligand/CD153 (CD30L) and CD40L/CD154. Furthermore, the expression of some of these proteins in mast cells has been associated with tumorigenesis, and mast cells have been found to be increased in number in the basal cell carcinoma (BCC) lesion. In this study, we have examined the expression of TNF-alpha, CD30L and CD40L immunoreactivity in mast cells in the healthy-looking skin and lesional skin of ten patients with superficial spreading BCC. Also, the counterparts of these molecules, TNF receptor (TNFR) I and II as well as CD30 and CD40, were analysed immunohistochemically. We found that numbers of mast cells and Kit-positive cells were significantly increased in the dermal BCC lesion. The percentage of CD30L-positive mast cells and the number of CD30-positive cells were significantly increased in the upper dermis of the BCC lesion as well. In addition, the numbers of TNF-alpha-positive mast cells and cells with TNFRI and TNFRII were markedly increased in the upper lesional dermis. In contrast, no mast cells positive for CD40L could be detected, even though the lesional dermis contained increased numbers of CD40 positive cells. The BCC epithelium was positive for TNFRI, TNFRII and CD40, but not for CD30, though the larger basal buds appeared to be less intensely stained for TNFRI and CD40. In conclusion, mast cells positive for CD30L and TNF-alpha, but not CD40L, are increased in number in the lesional dermis in BCC. These data suggest plausible pathways whereby mast cells can be activated and to interact with other cells and thereby contribute to the tumorigenesis in BCC.

Cancer-associated immune-mediated syndromes: Pathogenic values and clinical implementation

The ability of tumors to provoke formation of cancer-associated secondary immunodeficiency (CASID) with predominant suppression of CMI and cancer-associated secondary immunodeficiency with clinical autoimmunity syndrome (CASICAS) with triggering of a set of the autoimmune deviations is appearing to be a key event in the restriction of hosts' anti-tumor immunity. Earlier the existence of the above-mentioned syndromes was demonstrated in BCC and GBM patients. In order to reach a point where immunological phenotypes in GBM and BCC can be clarified clinically and, partly, pathogenically, we have conducted a series of studies of typical and atypical types of immune responsiveness in patients with GBM and BCC. For GBM and BCC three scenarios of the involvement of the immune responsiveness have been established in a series of our studies, i.e., (i) malignancy with no immunopathology, (ii) malignancy as CASID, and (iii) malignancy as CASICAS. All of those scenarios demonstrated significant differences in their immune-mediated manifestations which, in turn, were proven to reveal close associative relationships with a specific clinicopathologic type and clinical manifestations of the tumor. CASID and CASICAS share two common features, i.e., (i) signs of immunodeficiency and (ii) a tandem of the deviations within the adaptive and innate links of the host immune responsiveness. At the same time, CASID and CASICAS are distinct pathogenically and clinically, and in terms of depth of the immune deviations observed, CASID patients manifest a breakage in both links, whereas in CASICAS patients, a breakage in the adaptive link would dominate. To get these differences clarified, we summarized major types of the immune imbalances and sets of clinical and clinicopathologic manifestations to illustrate the above-mentioned features in CASID and CASICAS patients. There are distinct close correlations between clinicopathologic features of the disease course and sets of the immune-mediated imbalances in patients harboring the tumors. The latter implicates a panel of the new immunodiagnostic and immunoprognostic criteria for patients with solid tumors, i.e., BCC, MCC and GB, which is of great value for clinical practice. In particular, the blood levels of some of the immunocompetent cells, state of their functional activity, serum titers of the antigenic markers and autoantibodies, apoptotic parameters, and others may be accepted as additional and clinically informative criteria to be implemented for immunological monitoring and immunotherapy of patients with solid tumors.

Preclinical pharmacokinetics, pharmacodynamics, and activity of a humanized anti-CD40 antibody (SGN-40) in rodents and non-human primates

1. Cell-surface expression of CD40 in B-cell malignancies and multiple solid tumors has raised interest in its potential use as a target for antibody-based cancer therapy. SGN-40, a humanized monoclonal anti-CD40 antibody, mediates antibody-dependent cytotoxicity and inhibits B-cell tumor growth in vitro, properties of interest for the treatment of cancers, and is currently in Phase I clinical trials for B-cell malignancies. In this study, we determined in vivo activity and pharmacokinetics properties of SGN-40. 2. Effect of SGN-40 in xenograft model of CD40-expressing B-cell lymphoma in severe-combined immune deficiency mice and its in vivo pharmacokinetics properties in normal mice, rats and cynomolgus monkeys were studied. 3. Treatment with SGN-40 significantly increased the survival of mice xenografted with human B-cell lymphoma cell line. SGN-40 exhibited nearly 100% bioavailability in mice and it cleared faster when given at a low dose. In monkeys, clearance of SGN-40 was also much faster at low dose, suggesting nonlinear pharmacokinetics in these species. In rats, however, SGN-40 clearance at all tested doses was similar, suggesting that pharmacokinetics were linear in this dose range in rats. Administration of SGN-40 to monkeys also produced marked, dose-dependent, and persistent depletion of peripheral CD20(+) B lymphocytes. 4. Data presented in this report suggest that SGN-40 is active in in vivo, and based upon interspecies scaling, SGN-40 clearance in humans is predicted to be similar to observed SGN-40 clearance in monkeys. These data suggest that SGN-40 has appropriate pharmacokinetic properties that support its clinical use.

Combined prophylactic and therapeutic cancer vaccine: Enhancing CTL responses to HPV16 E2 using a chimeric VLP in HLA-A2 mice

We identified the strategies to induce a CTL response to human papillomavirus (HPV) 16 E2 in HLA-A2 transgenic mice (AAD). A chimeric HPV16 virus-like particle (VLP) that includes full length HPV16 E7 and E2 (VLP-E7E2) was generated. The combination of E2 and E7 has the advantage that E2 is expressed in early dysplasia and neoplasia lesions, where E7 is expressed in more advance lesions. Since T cell response to E2 is less defined, we first evaluated the strategies to enhancing CD8(+) T cell responses to HPV E7, using different combinations of immune-modulators with VLP-E7E2. Data showed that the CTL response to E7 could be significantly enhanced by coinjection of GM-CSF and anti-CD40 antibodies with chimeric VLP-E7E2 without adjuvant. However, using the same combination, a low level of CD8(+) T cell response to E2 was detected. To enhance the CD8+ T cell response to E2, we analyzed T cell epitopes from E2 sequence. A heterogenous prime-boost with chimeric VLP-E7E2 and E2 peptides was performed. The data showed that the priming with chimeric VLP-E7E2, followed by boosting with E2 peptides, gave a better CTL response than 2 immunizations with E2 peptides. The enhanced immunity is due to the increase of CD11c(+) and CD11c(+) CD40(+) double positive dendritic cells in mice that received immune-modulators, GM-CSF and anti-CD40. Furthermore, the level of anti-L1 antibodies remains similar in mice immunized with chimeric VLP with/without immune-modulators. Thus, the data suggested that the chimeric VLP-E7E2 has a therapeutic potential for the treatment of HPV-associated CINs and cancer without diminishing VLPs potential as a prophylactic vaccine by inducing anti-L1 antibodies against free virus.

Preclinical antilymphoma activity of a humanized anti-CD40 monoclonal antibody, SGN-40

SGN-40 is a humanized IgG1 antihuman CD40 that is currently in a phase I clinical trial for the treatment of multiple myeloma. As surface CD40 expression on B-lineage cells is maintained from pro-B cells to plasma cells, SGN-40 may be applicable to treatment of other B-cell neoplasias, including non-Hodgkin's lymphoma. In this study, we examined potential in vitro and in vivo anti-B-lineage lymphoma activity of SGN-40. Recombinant SGN-40 was expressed and purified from Chinese hamster ovary cells and characterized based on binding affinity, specificity, and normal B-cell stimulation. The ability of SGN-40 to target neoplastic B cells was examined in vitro by proliferation inhibition, cytotoxicity, and antibody-dependent cell cytotoxicity assays and in vivo by human lymphoma xenograft models. Recombinant SGN-40 showed high affinity, Kd of approximately 1 nmol/L, and specific binding to CD40. Whereas SGN-40 was a weak agonist in stimulating normal B-cell proliferation in the absence of IL-4 and CD40L, it delivered potent proliferation inhibitory and apoptotic signals to, and mediated antibody-dependent cytotoxicity against, a panel of high-grade B-lymphoma lines. These in vitro antilymphoma effects were extended to disseminated and s.c. xenograft CD40 tumor models. In these xenograft models, the antitumor activity of SGN-40 was comparable with that of rituximab. The preclinical in vitro and in vivo antilymphoma activity of SGN-40 observed in this study provides a rationale for the clinical testing of SGN-40 in the treatment of CD40+ B-lineage lymphomas.

Thyroid cancers express CD-40 and CD-40 ligand: cancers that express CD-40 ligand may have a greater risk of recurrence in young patients

The immune response might suppress thyroid cancer recurrence. Although the factors that control this are unknown, CD-40 and CD-40 ligand might be important. To test this, we stained 36 papillary (PTC) and four follicular (FTC) thyroid carcinomas for CD-40 (n = 37) and CD-40 ligand (n = 36) and graded staining from absent (grade 0) to intense (grade 3). Follicular cells of the majority of thyroid tumors expressed CD-40 (30/37, 81%) and CD-40 ligand (15/24, 69%). Cancers from young patients (< or =21 years of age) that expressed CD-40 contained more numerous lymphocytes/high-power field (36 +/- 11) than cancers that failed to express CD-40 (4 +/- 3, p = 0.01), but there was no correlation with clinical outcome. Among young patients, CD-40 ligand expression was more intense in multifocal (1.1 +/- 0.2 vs. 0.45 +/- 0.2, p = 0.037), aggressive (1.14 +/- 0.14 vs. 0.65 +/- 0.2, p = 0.05) and recurrent tumors (1.2 +/- 0.2 vs. 0.65 +/- 0.2, p = 0.05) and associated with reduced disease-free survival (p = 0.03). We conclude that the majority of thyroid cancers express CD-40 and CD-40 ligand. In patients < or =21 years of age, tumors with intense expression of CD-40 ligand are more often multifocal, aggressive, and recurrent.

Construction of recombinant eukaryotic expression plasmid containing murine CD40 ligand gene and its expression in H22 cells

AIM: To construct a recombinant murine CD40 ligand (mCD40L) eukaryotic expression vector for gene therapy and target therapy of hepatocellular carcinoma (HCC).

METHODS: mCD40L cDNA was synthesized by RT-PCR with the specific primers and directly cloned into T vector to generate middle recombinant. After digestion with restriction endonuclease, the target fragment was subcloned into the multi-clone sites of the eukaryotic vector. The constructed vector was verified by enzyme digestion and sequencing, and the product expressed was detected by RT-PCR and immunofluorescence methods.

RESULTS: The full-length mCD40L-cDNA was successfully cloned into the eukaryotic vector through electrophoresis, and mCD40L gene was integrated into the genome of infected H22 cells by RT-PCR. Murine CD40L antigen molecule was observed in the plasma of mCD40L-H22 by indirect immuno-fluorescence staining.

CONCLUSION: The recombined mCD40L eukaryotic expression vector can be expressed in H22 cell line. It provides experimental data for gene therapy and target therapy of hepatocellular carcinoma.

Cancer therapy: new targets for chemotherapy

The number two cause of mortality in developed countries is cancer. Despite the enormous effort put into cancer prevention, early diagnosis and treatment, it is likely that the incidence of the cancer morbidity and mortality will increase for the foreseeable future. This is due to various factors such as increased life expectancy, changes in environment and also the socio-economic situation around the world. Some cancer attracts more attention than others and increasingly epidemiological information is reaching the general public and is beginning to influence behavior. It is now well recognized that, for example, 1 of 8 women in the industrialized world will be diagnosed with breast cancer. Additionally, a strong correlation was established between lung cancer incidence and smoking and it is broadly accepted that the incidence of colon cancer is directly related to age and diet, and has been increasing over time. The current failure of preventive measures to significantly reduce the increasing incidence of these common tumors illustrates the importance of effective cancer treatment strategies, including chemotherapy. The combination of various anticancer drugs, given together with surgery and radiotherapy, gives hope to many patients. There has been recent evidence of improved therapeutic outcome with recent approaches and newer agents but for continuing effective chemotherapeutic treatment there is a need for a detailed understanding of their mechanisms of action and on the rationale of their application. This review attempts to provide up-to-date information regarding the development of new and innovative treatment strategies for cancer chemotherapy. Virtually, every year several of new targets for cancer therapy on both, cellular and molecular levels, are identified and new drugs enter not only clinical trials but also are included in well accepted and documented therapeutic protocols. As this review is in addition to our review published previously (Medical Principles and Practice 11, 2002, 117-125), we have tried to include new and innovative targets and drugs that attract attention at present. Although it is not possible to provide a complete list of all achievements and cover all work done in this field, we hope to be able to give some insight into this rapidly developing area.