Role for CD40-CD40 ligand interactions in the immune response to solid tumours

Immunotherapeutic prospects and progress in bladder cancer

Bladder cancer is one of the most common malignant tumours of the urogenital system, with high morbidity and mortality. In most cases, surgery is considered the first choice of treatment, followed by adjuvant chemotherapy. However, the 5-year recurrence rate is still as high as 65% in patients with non-invasive or in situ tumours and up to 73% in patients with slightly more advanced disease at initial diagnosis. Various treatment methods for bladder cancer have been developed, and hundreds of new immunotherapies are being tested. To date, only a small percentage of people have had success with new treatments, though studies have suggested that the combination of immunotherapy with other therapies improves treatment efficiency and positive outcomes for individuals, with great hopes for the future. In this article, we summarize the origins, therapeutic mechanisms and current status of research on immunotherapeutic agents for bladder cancer.

Harnessing the potential of CD40 agonism in cancer therapy

CD40 is a member of the tumor necrosis factor (TNF) receptor superfamily of receptors expressed on a variety of cell types. The CD40-CD40L interaction gives rise to many immune events, including the licensing of dendritic cells to activate CD8+ effector T cells, as well as the facilitation of B cell activation, proliferation, and differentiation. In malignant cells, the expression of CD40 varies among cancer types, mediating cellular proliferation, apoptosis, survival and the secretion of cytokines and chemokines. Agonistic human anti-CD40 antibodies are emerging as an option for cancer treatment, and early-phase clinical trials explored its monotherapy or combination with radiotherapy, chemotherapy, immune checkpoint blockade, and other immunomodulatory approaches. In this review, we present the current understanding of the mechanism of action for CD40, along with results from the clinical development of agonistic human CD40 antibodies in cancer treatment (selicrelumab, CDX-1140, APX005M, mitazalimab, 2141-V11, SEA-CD40, LVGN7409, and bispecific antibodies). This review also examines the safety profile of CD40 agonists in both preclinical and clinical settings, highlighting optimized dosage levels, potential adverse effects, and strategies to mitigate them.

Identification of disulfidptosis-related subgroups and prognostic signatures in lung adenocarcinoma using machine learning and experimental validation

Background

Disulfidptosis is a newly identified variant of cell death characterized by disulfide accumulation, which is independent of ATP depletion. Accordingly, the latent influence of disulfidptosis on the prognosis of lung adenocarcinoma (LUAD) patients and the progression of tumors remains poorly understood.

Methods

We conducted a multifaceted analysis of the transcriptional and genetic modifications in disulfidptosis regulators (DRs) specific to LUAD, followed by an evaluation of their expression configurations to define DR clusters. Harnessing the differentially expressed genes (DEGs) identified from these clusters, we formulated an optimal predictive model by amalgamating 10 distinct machine learning algorithms across 101 unique combinations to compute the disulfidptosis score (DS). Patients were subsequently stratified into high and low DS cohorts based on median DS values. We then performed an exhaustive comparison between these cohorts, focusing on somatic mutations, clinical attributes, tumor microenvironment, and treatment responsiveness. Finally, we empirically validated the biological implications of a critical gene, KYNU, through assays in LUAD cell lines.

Results

We identified two DR clusters and there were great differences in overall survival (OS) and tumor microenvironment. We selected the "Least Absolute Shrinkage and Selection Operator (LASSO) + Random Survival Forest (RFS)" algorithm to develop a DS based on the average C-index across different cohorts. Our model effectively stratified LUAD patients into high- and low-DS subgroups, with this latter demonstrating superior OS, a reduced mutational landscape, enhanced immune status, and increased sensitivity to immunotherapy. Notably, the predictive accuracy of DS outperformed the published LUAD signature and clinical features. Finally, we validated the DS expression using clinical samples and found that inhibiting KYNU suppressed LUAD cells proliferation, invasiveness, and migration in vitro.

Conclusions

The DR-based scoring system that we developed enabled accurate prognostic stratification of LUAD patients and provides important insights into the molecular mechanisms and treatment strategies for LUAD.

Next Generation CD40 Agonistic Antibodies for Cancer Immunotherapy

The clinical use of anti-CD40 agonist monoclonal antibodies (mAbs) is aimed at recruiting the immune system to fight the tumor cells. This approach has been demonstrated to be effective in various preclinical models. However, human CD40 Abs displayed only modest antitumor activity in cancer patients, characterized by low efficacy and dose-limiting toxicity. While recent studies highlight the importance of engineering the Fc region of human CD40 mAbs to optimize their agonistic potency, toxicity remains the main limiting factor, restricting clinical application to suboptimal doses. Here, we discuss the current challenges in realizing the full potential of CD40 mAbs in clinical practice, and describe novel approaches designed to circumvent the systemic toxicity associated with CD40 agonism.

Synergistic immunotherapy of glioblastoma by dual targeting of IL-6 and CD40

Immunologically-cold tumors including glioblastoma (GBM) are refractory to checkpoint blockade therapy, largely due to extensive infiltration of immunosuppressive macrophages (Mϕs). Consistent with a pro-tumor role of IL-6 in alternative Mϕs polarization, we here show that targeting IL-6 by genetic ablation or pharmacological inhibition moderately improves T-cell infiltration into GBM and enhances mouse survival; however, IL-6 inhibition does not synergize PD-1 and CTLA-4 checkpoint blockade. Interestingly, anti-IL-6 therapy reduces CD40 expression in GBM-associated Mϕs. We identify a Stat3/HIF-1α-mediated axis, through which IL-6 executes an anti-tumor role to induce CD40 expression in Mϕs. Combination of IL-6 inhibition with CD40 stimulation reverses Mϕ-mediated tumor immunosuppression, sensitizes tumors to checkpoint blockade, and extends animal survival in two syngeneic GBM models, particularly inducing complete regression of GL261 tumors after checkpoint blockade. Thus, antibody cocktail-based immunotherapy that combines checkpoint blockade with dual-targeting of IL-6 and CD40 may offer exciting opportunities for GBM and other solid tumors.

OMIC signatures to understand cancer immunosurveillance and immunoediting: Melanoma and immune cells interplay in immunotherapy

Melanoma is the deadliest form of skin cancer. Cutaneous melanomas usually originate from exposure to the mutagenic effects of ultraviolet radiation, and as such they exhibit the highest rate of somatic mutations than any other human cancer, and an extensive expression of neoantigens concurrently with a dense infiltrate of immune cells. The coexistence of high immunogenicity and high immune cell infiltration may sound contradictory for cancers carrying a gloomy outcome. However, recent studies have unveiled a variety of immunosuppressive mechanisms that often permeate the tumor microenvironment and that are responsible for tumor escaping from immunosurveillance mechanisms. Nonetheless, this particular immune profile has opened a new window of treatments based on immunotherapy that have significantly improved the clinical outcome of melanoma patients. Still, positive and complete therapy responses have been limited, and this particular cancer continues to be a major clinical challenge. The transcriptomic signatures of those patients with clinical benefit and those with progressive disease have provided a more complete picture of the universe of interactions between the tumor and the immune system. In this review, we integrate the results of the immunotherapy clinical trials to discuss a novel understanding of the mechanisms guiding cancer immunosurveillance and immunoediting. A clear notion of the cellular and molecular processes shaping how the immune system and the tumor are continuously coevolving would result in the rational design of combinatory therapies aiming to counteract the signaling pathways and cellular processes responsible for immunoescape mechanisms and provide clinical benefit to immunotherapy nonresponsive patients.

Development of CDX-1140, an agonist CD40 antibody for cancer immunotherapy

Limitations of immunotherapy include poorly functioning events early in the immune response cycle, such as efficient antigen presentation and T cell priming. CD40 signaling in dendritic cells leads to upregulation of cell surface costimulatory and MHC molecules and the generation of cytokines, which promotes effective priming of CD8+ effector T cells while minimizing T cell anergy and the generation of regulatory T cells. This naturally occurs through interaction with CD40 ligand (CD40L) expressed on CD4+ T-helper cells. CD40 signaling can also be achieved using specific antibodies, leading to several agonist CD40 antibodies entering clinical development. Our approach to select a CD40 agonist antibody was to define a balanced profile between sufficiently strong immune stimulation and the untoward effects of systemic immune activation. CDX-1140 is a human IgG2 antibody that activates DCs and B cells and drives NFkB stimulation in a CD40-expressing reporter cell line. These activities are Fc-independent and are maintained using an F(ab')2 fragment of the antibody. CDX-1140 binds outside of the CD40L binding site, and addition of recombinant CD40L greatly enhances DC and B activation by CDX-1140, suggesting that CDX-1140 may act synergistically with naturally expressed CD40L. CDX-1140 also has both direct and immune-mediated anti-tumor activity in xenograft models. CDX-1140 does not promote cytokine production in whole blood assays and has good pharmacodynamic and safety profiles in cynomolgus macaques. These data support the potential of CDX-1140 as part of a cancer therapy regimen, and a phase 1 trial has recently commenced.

Functional Plasticity of Gamma Delta T Cells and Breast Tumor Targets in Hypoxia

Interactions between immune and tumor cells in the tumor microenvironment (TME) often impact patient outcome, yet remain poorly understood. In addition, the effects of biophysical features such as hypoxia [low oxygen (O₂)] on cells within the TME may lead to tumor evasion. Gamma delta T cells (γδTcs) naturally kill transformed cells and are therefore under development as immunotherapy for various cancers. Clinical trials have proven the safety of γδTc immunotherapy and increased circulating γδTc levels correlate with improved patient outcome. Yet, the function of γδTc tumor infiltrating lymphocytes in human breast cancer remains controversial. Breast tumors can be highly hypoxic, thus therapy must be effective under low O₂ conditions. We have found increased infiltration of γδTc in areas of hypoxia in a small cohort of breast tumors; considering their inherent plasticity, it is important to understand how hypoxia influences γδTc function. In vitro, the cell density of expanded primary healthy donor blood-derived human γδTc decreased in response to hypoxia (2% O₂) compared to normoxia (20% O₂). However, the secretion of macrophage inflammatory protein 1α (MIP1α)/MIP1β, regulated on activation, normal T cell expressed and secreted (RANTES), and CD40L by γδTc were increased after 40 h in hypoxia compared to normoxia concomitant with the stabilization of hypoxia inducible factor 1-alpha protein. Mechanistically, we determined that natural killer group 2, member D (NKG2D) on γδTc and the NKG2D ligand MHC class I polypeptide-related sequence A (MICA)/B on MCF-7 and T47D breast cancer cell lines are important for γδTc cytotoxicity, but that MIP1α, RANTES, and CD40L do not play a direct role in cytotoxicity. Hypoxia appeared to enhance the cytotoxicity of γδTc such that exposure for 48 h increased cytotoxicity of γδTc against breast cancer cells that were maintained in normoxia; conversely, breast cancer lines incubated in hypoxia for 48 h prior to the assay were largely resistant to γδTc cytotoxicity. MICA/B surface expression on both MCF-7 and T47D remained unchanged upon exposure to hypoxia; however, ELISAs revealed increased MICA shedding by MCF-7 under hypoxia, potentially explaining resistance to γδTc cytotoxicity. Despite enhanced γδTc cytotoxicity upon pre-incubation in hypoxia, these cells were unable to overcome hypoxia-induced resistance of MCF-7. Thus, such resistance mechanisms employed by breast cancer targets must be overcome to develop more effective γδTc immunotherapies.

Cd40 Activation as Potential Tool in Malignant Neoplasms

Background

CD40, a cell surface molecule, is expressed on B-cell malignancies and many different solid tumors. It is capable of mediating diverse biological phenomena such as the induction of apoptosis in tumors and stimulation of the immune response. It has thus been studied as a possible target for antitumor therapy. The general aim of this review is to focus the attention of clinical oncologists on the involvement of CD40 in tumors and the rationale of CD40-activation-based therapies in new, biologically oriented antitumor protocols.

Methods

A Medline review of published papers about the role of CD40 activation in cancer therapy.

Results

Many authors have shown that CD40 activation promotes apoptotic death of tumor cells and that the presence of the molecule on the surface of carcinoma lines is an important factor in the generation of tumor-specific T-cell responses that contribute to tumor cell elimination. The CD40 ligand (CD40L) is the natural ligand for CD40; it is expressed primarily on the surface of activated T lymphocytes. Preclinical studies suggest that CD40-CD40L interaction could be useful for cytotoxicity against CD40-expressing tumors and for immune stimulation. Tumor inhibition was observed when tumor cells were treated with agonistic anti-CD40 monoclonal antibodies or with the soluble form of CD40L. The results of the first phase I clinical trial to treat cancer patients with subcutaneous injection of recombinant human CD40L have been recently reported. Immunohistochemical studies have revealed that detection of CD40 in primary cutaneous malignant melanoma and lung cancer may have a negative prognostic value. Interestingly, up-regulation of CD40 was observed in the tumor vessels of renal carcinomas and Kaposi's sarcoma, suggesting possible involvement of CD40 in tumor angiogenesis. Recently, it has also been shown that CD40 engagement on endothelial cells induces in vitro tubule formation and expression of matrix metalloproteinases, two processes involved in the neovascularization and progression of tumors.

Conclusions

CD40 activation represents an exciting target for hematological malignancies and solid tumors expressing the molecule, but its functional role in cancer development still remains unclear and controversial.

Advanced new strategies for metastatic cancer treatment by therapeutic stem cells and oncolytic virotherapy

The field of therapeutic stem cell and oncolytic virotherapy for cancer treatment has rapidly expanded over the past decade. Oncolytic viruses constitute a promising new class of anticancer agent because of their ability to selectively infect and destroy tumor cells. Engineering of viruses to express anticancer genes and specific cancer targeting molecules has led to the use of these systems as a novel platform of metastatic cancer therapy. In addition, stem cells have a cancer specific migratory capacity, which is available for metastatic cancer targeting. Prodrug activating enzyme or anticancer cytokine expressing stem cells successfully inhibited the proliferation of cancer cells. Preclinical models have clearly demonstrated anticancer activity of these two platforms against a number of different cancer types and metastatic cancer. Several systems using therapeutic stem cells or oncolytic virus have entered clinical trials, and promising results have led to late stage clinical development. Consequently, metastatic cancer therapies using stem cells and oncolytic viruses are extremely promising. The following review will focus on the metastatic cancer targeting mechanism of therapeutic stem cells and oncolytic viruses, and potential challenges ahead for advancing the field.

Induction of Apoptosis in Cancer Cells of pre-B ALL Patients after Exposure to Platelets, Platelet-Derived Microparticles and Soluble CD40 Ligand

Objective

The in vitro treatment of tumor cells with platelet (Plt) causes inhibition of tumor cell growth, although mechanism of this effect is not clear yet. Induction of apoptosis has been proposed as a mechanism of Plt effects on tumor cells. The purpose of this study was to clarify the role of Plts and Plt-derived components in the induction of apoptosis in the blood mononuclear cells of patients with leukemia.

Materials and Methods

In this experimental study, peripheral blood mononuclear cells (PBMCs) were isolated from whole blood of five patients with childhood B-precursor acute lymphoblastic leukemia (pre-B ALL) and encountered with Plts, Plt-derived microparticles (Plt-MPs) as well as purified soluble CD40L (sCD40L). After 48 hours of co-culture, the anti-cancer activity of the aforementioned factors was surveyed using examination of apoptosis markers of the cells including active caspase-3 and CD95 using ELISA and flow cytometer techniques, respectively. Additionally, staining of the cells with 7-Aminoactinomycin D (7-AAD) was evaluated by flow cytometer technique. Trypan blue exclusion test and WST-1 method were also used to compare the death/survival status of the cells.

Results

Levels of CD95 and caspase-3 were significantly increased in the all treated groups (P<0.05). On the other hand, trypan blue, 7-AAD and WST-1 methods showed significantly lower number of the live cells in the treated groups (P<0.05).

Conclusion

This study can show the ability of Plts, Plt-MPs and sCD40L for the induction of apoptosis in PBMCs of pre-B-ALL patients. Further studies are necessary to elucidate the different effects of platelets on cancer cells in vitro and in vivo.

Preclinical Rationale and Clinical Considerations for Radiotherapy Plus Immunotherapy: Going Beyond Local Control

The use of radiation for cancer therapy has expanded and sparked interest in possible synergistic effects by combining it with current immunotherapies. In this review, we present a case of a patient who responded to programmed cell death 1 (PD1) blockade and radiation therapy and discuss possible mechanisms. We provide background on the blockade of the cytotoxic T-lymphocyte antigen 4 (CTLA-4) and PD1 checkpoints and highlight future immune-based therapies that may synergize with radiation, including cytosine-phosphate-guanine vaccines, OX40 agonists, CD40 agonists, regulatory T-cell depletion, and metabolic "rewiring" of cancer cells. Clinical considerations are noted for combining radiation with immunotherapies to extend the benefit of immunotherapy to more patients. New trials are needed to appropriately investigate the best sequencing and radiation dose to prime an immune response and to identify predictive biomarkers of such responses.

Turning tumour cells into antigen presenting cells: The next step to improve cancer immunotherapy?

Downregulation/loss of the antigen presentation is a major immune escape mechanism in cancer. It allows tumour cells to become 'invisible' and avoid immune attack by antitumour T cells. In tumour harbouring properties of professional antigen presenting cells (i.e. tumour B cells in lymphoma), downregulation/loss of the antigen presentation may also prevent direct priming of naïve T cells by tumour cells. Here, we review treatments that may induce/restore antigen presentation by the tumour cells. These treatments may increase the generation of antitumour T cells and/or their capacity to recognise and eliminate tumour cells. By forcing tumour cells to present their antigens, these treatments may sensitise patients to T cell-based immunotherapies, including checkpoint inhibitors.

Potential predictive role of chemotherapy-induced changes of soluble CD40 ligand in untreated advanced pancreatic ductal adenocarcinoma

Pancreas ductal adenocarcinoma lacks predictive biomarkers. CD40 is a member of the tumor necrosis factor superfamily. CD40-sCD40L interaction is considered to contribute to the promotion of tumor cell growth and angiogenesis. The aim of the present study was to investigate the role of serum sCD40L as a predictor in metastatic pancreatic cancer. We evaluated 27 consecutive pancreatic cancer patients treated with FOLFIRINOX (21 patients) or gemcitabine plus nab-paclitaxel combination (six patients). The sCD40L level was measured in serum by enzyme-linked immunosorbent assay at baseline, at first evaluation (all patients), and at time to progression (18 patients). The radiological response was evaluated according to the Response Evaluation Criteria in Solid Tumors, Version 1.1. The Wilcoxon signed-rank test was used to compare pre-post treatment sCD40L levels with respect to clinical response, while Pearson's correlation coefficient was used for the correlation between sCD40L and CA19.9 pre- and post-treatment. The Kruskal-Wallis test was also conducted for further comparisons. We observed a statistically significant reduction in the sCD40L level after 3 months of treatment in patients with partial response (11,718.05±7,097.13 pg/mL vs 4,689.42±5,409.96 pg/mL; P<0.01). Conversely, in patients with progressive disease, the biomarker statistically increased in the same time (9,351.51±7,356.91 pg/mL vs 22,282.92±11,629.35 pg/mL; P<0.01). This trend of sCD40L was confirmed in 18 patients at time to progression after the first evaluation. No differences were recorded within the stable disease group. Moreover, there was a positive correlation between the sCD40L and CA19.9 pre-post treatment variation percentage (Pearson's correlation coefficient =0.52; P<0.05). Our data suggest a possible predictive role of sCD40L in pancreatic cancer patients, similar to CA19.9.

Vaccination Produces CD4 T Cells with a Novel CD154-CD40-Dependent Cytolytic Mechanism

The discovery of new vaccines against infectious diseases and cancer requires the development of novel adjuvants with well-defined activities. The TLR4 agonist adjuvant GLA-SE elicits robust Th1 responses to a variety of vaccine Ags and is in clinical development for both infectious diseases and cancer. We demonstrate that immunization with a recombinant protein Ag and GLA-SE also induces granzyme A expression in CD4 T cells and produces cytolytic cells that can be detected in vivo. Surprisingly, these in vivo CTLs were CD4 T cells, not CD8 T cells, and this cytolytic activity was not dependent on granzyme A/B or perforin. Unlike previously reported CD4 CTLs, the transcription factors Tbet and Eomes were not necessary for their development. CTL activity was also independent of the Fas ligand-Fas, TRAIL-DR5, and canonical death pathways, indicating a novel mechanism of CTL activity. Rather, the in vivo CD4 CTL activity induced by vaccination required T cell expression of CD154 (CD40L) and target cell expression of CD40. Thus, vaccination with a TLR4 agonist adjuvant induces CD4 CTLs, which kill through a previously unknown CD154-dependent mechanism.

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.

Efficacy of Zhuling polyporus polysaccharide with BCG to inhibit bladder carcinoma

There is growing interest in reducing Bacille Calmette-Guerin (BCG) side effects while keeping intact its therapeutic efficacy. In the present study, we evaluated the efficacy of Sclerotia of Polyporus umbellatus FRIES (Zhuling) and its main ingredient Polyporus Polysaccharide (PPS) to attenuate side effects of BCG therapy in vivo. The results show that bladder cancer development in model rats exhibited significantly reduced cancer invasiveness with Zhuling PPS combined with BCG. Flow cytometric (FCM) analysis showed expression of costimulatory molecules CD86, CD40, and TLR4/CD14 significantly increased with Zhuling PPS in combination with BCG. Similarly, immunohistochemical analysis revealed stronger CD86 and CD40 staining. Our findings show Zhuling PPS strongly reduced side effects and displayed synergistic effects during BCG instillation in rat bladder cancer models. The findings also suggest that the attenuation effect may result from direct activation of dendritic cell (DC) TLR4.

Phase I study of the CD40 agonist antibody CP-870,893 combined with carboplatin and paclitaxel in patients with advanced solid tumors

CD40 is a cell-surface molecule that critically regulates immune responses. CP-870,893 is a fully human, CD40-specific agonist monoclonal antibody (mAb) exerting clinical antineoplastic activity. Here, the safety of CP-870,893 combined with carboplatin and paclitaxel was assessed in a Phase I study. Patients with advanced solid tumors received standard doses of paclitaxel and carboplatin on day 1 followed by either 0.1 mg/Kg or 0.2 mg/Kg CP-870,893 on day 3 (Schedule A) or day 8 (Schedule B), repeated every 21 d. The primary objective was to determine safety and maximum-tolerated dose (MTD) of CP-870,893. Secondary objectives included the evaluation of antitumor responses, pharmacokinetics and immune modulation. Thirty-two patients were treated with CP-870,893, 16 patients on each schedule. Two dose-limiting toxicities were observed (grade 3 cytokine release and transient ischemic attack), each at the 0.2 mg/Kg dose level, which was estimated to be the MTD. The most common treatment-related adverse event was fatigue (81%). Of 30 evaluable patients, 6 (20%) exhibited partial responses constituting best responses as defined by RECIST. Following CP-870,893 infusion, the peripheral blood manifested an acute depletion of B cells associated with upregulation of immune co-stimulatory molecules. T-cell numbers did not change significantly from baseline, but transient tumor-specific T-cell responses were observed in a small number of evaluable patients. The CD40 agonist mAb CP-870,893, given on either of two schedules in combination with paclitaxel and carboplatin, was safe for patients affected with advanced solid tumors. Biological and clinical responses were observed, providing a rationale for Phase II studies.

Multifunctional CD40L: pro- and anti-neoplastic activity

The CD40 ligand is a type I transmembrane protein that belongs to a tumor necrosis factor (TNF) superfamily. It is present not only on the surface of activated CD4+ T cells, B cells, blood platelets, monocytes, and natural killer (NK) cells but also on cancer cells. The receptor for ligand is constitutively expressed on cells, TNF family protein: CD40. The role of the CD40/CD40L pathway in the induction of body immunity, in inflammation, or in hemostasis has been well documented, whereas its involvement in neoplastic disease is still under investigation. CD40L ligand may potentiate apoptosis of tumor cells by activation of nuclear factor-κB (NF-κB), AP-1, CD95, or caspase-depended pathways and stimulate host immunity to defend against cancer. Although CD40L has a major contribution to anti-cancer activity, many reports point at its ambivalent nature. CD40L enhance release of strongly pro-angiogenic factor, vascular endothelial growth factor (VEGF), and activator of coagulation, TF, the level of which is correlated with tumor metastasis. CD40L involvement in the inhibition of tumor progression has led to the emergence of not only therapy using recombinant forms of the ligand and vaccines in the treatment of cancer but also therapy consisting of inhibiting platelets-main source of CD40L. This article is a review of studies on the ambivalent role of CD40L in neoplastic diseases.

Combination of an agonistic anti-CD40 monoclonal antibody and the COX-2 inhibitor celecoxib induces anti-glioma effects by promotion of type-1 immunity in myeloid cells and T-cells

Malignant gliomas are heavily infiltrated by immature myeloid cells that mediate immunosuppression. Agonistic CD40 monoclonal antibody (mAb) has been shown to activate myeloid cells and promote antitumor immunity. Our previous study has also demonstrated blockade of cyclooxygenase-2 (COX-2) reduces immunosuppressive myeloid cells, thereby suppressing glioma development in mice. We therefore hypothesized that a combinatory strategy to modulate myeloid cells via two distinct pathways, i.e., CD40/CD40L stimulation and COX-2 blockade, would enhance anti-glioma immunity. We used three different mouse glioma models to evaluate therapeutic effects and underlying mechanisms of a combination regimen with an agonist CD40 mAb and the COX-2 inhibitor celecoxib. Treatment of glioma-bearing mice with the combination therapy significantly prolonged survival compared with either anti-CD40 mAb or celecoxib alone. The combination regimen promoted maturation of CD11b(+) cells in both spleen and brain, and enhanced Cxcl10 while suppressing Arg1 in CD11b(+)Gr-1(+) cells in the brain. Anti-glioma activity of the combination regimen was T-cell dependent because depletion of CD4(+) and CD8(+) cells in vivo abrogated the anti-glioma effects. Furthermore, the combination therapy significantly increased the frequency of CD8(+) T-cells, enhanced IFN-γ-production and reduced CD4(+)CD25(+)Foxp3(+) T regulatory cells in the brain, and induced tumor-antigen-specific T-cell responses in lymph nodes. Our findings suggest that the combination therapy of anti-CD40 mAb with celecoxib enhances anti-glioma activities via promotion of type-1 immunity both in myeloid cells and T-cells.

Pancreatic ductal adenocarcinoma: a review of immunologic aspects

With the continued failures of both early diagnosis and treatment options for pancreatic cancer, it is now time to comprehensively evaluate the role of the immune system on the development and progression of pancreatic cancer. It is important to develop strategies that harness the molecules and cells of the immune system to treat this disease. This review will focus primarily on the role of immune cells in the development and progression of pancreatic ductal adenocarcinoma and to evaluate what is known about the interaction of immune cells with the tumor microenvironment and their role in tumor growth and metastasis. We will conclude with a brief discussion of therapy for pancreatic cancer and the potential role for immunotherapy. We hypothesize that the role of the immune system in tumor development and progression is tissue specific. Our hope is that better understanding of this process will lead to better treatments for this devastating disease.

Anti-CD40-mediated cancer immunotherapy: an update of recent and ongoing clinical trials

The costimulatory molecule CD40 is a member of the tumor necrosis factor (TNF) receptor superfamily and is expressed on various antigen presenting cells (APCs) as well as some tumor cells. The binding to the natural ligand CD40L, which is expressed on T helper cells, leads to APC activation and thus enhancement of immune responses. Treatment with anti-CD40 monoclonal antibodies has been exploited in several cancer immunotherapy studies in mice and led to the development of anti-CD40 antibodies for clinical use. Here, Dacetuzumab and Lucatumumab are in the most advanced stage and are being tested as treatment for malignancies such as chronic lymphatic leukemia (CLL), Multiple Myeloma (MM), and non-Hodgkin's lymphoma (NHL). The promising results from these early clinical trials have encouraged clinical drug development in order to investigate the effect of CD40 mAbs in combination with other cancer immunotherapies, in particular interleukin (IL)-2. An in-depth analysis of this immunotherapy is provided elsewhere. In the present review, we provide an update of the most recent clinical trials with anti-CD40 antibodies. We present and discuss recent and ongoing clinical trials in this field, including clinical studies which combine anti-CD40 treatment with other cancer-treatments, such as Rituximab and Tremelimumab.

The therapeutic function of the chemokine RANTES on the H22 hepatoma ascites model

This study aimed at analyzing the therapeutic function of the chemokine RANTES on the H22 hepatoma ascites model and preliminarily explore the mechanism of RANTES in malignant ascites to provide an important reference for applying chemokines in anti-tumor therapy. The murine H22 hepatoma ascites model was used. Three treatment groups were analyzed: a RANTES treatment group, an IL-2 control group, and an NS control group. Two regimens of early treatment and late treatment were designed, and the therapeutic effect of RANTES on malignant ascites was studied by measuring changes in mouse body weight and abdominal circumference and observing the survival time. The expression of TNF-α, IFN-γ, TGF-β1, and MCP-1 in mouse ascites was detected by ELISA, and the chemotactic function of RANTES on B lymphocytes and T lymphocytes was analyzed by flow cytometry. In the early and late treatment regimens, RANTES could effectively inhibit the increase in mouse body weight and abdominal circumference in the murine H22 hepatoma ascites model. The secretion of TNF-α and IFN-γ, which had anti-tumor effects, was higher in the RANTES treatment group than in the control groups (P < 0.05), whereas the secretion of TGF-β1 and MCP-1, which promoted tumor growth, invasion, and metastasis, was lower than in the control groups (P < 0.05). RANTES had chemotactic effects on CD4(+) and CD8(+) T lymphocytes; therefore, the percentage of CD3, CD4, and CD8 in the mouse ascites in the RANTES treatment group was significantly higher than in the NS control and IL-2 treatment groups, and the CD4/CD8 ratio was also significantly higher. RANTES can effectively inhibit the increase in body weight and abdominal circumference and significantly extend survival time in mice in the H22 hepatoma ascites model.

Pancreatic ductal adenocarcinoma: a review of immunologic aspects

With the continued failures of both early diagnosis and treatment options for pancreatic cancer, it is now time to comprehensively evaluate the role of the immune system on the development and progression of pancreatic cancer. It is important to develop strategies that harness the molecules and cells of the immune system to treat this disease. This review will focus primarily on the role of immune cells in the development and progression of pancreatic ductal adenocarcinoma and to evaluate what is known about the interaction of immune cells with the tumor microenvironment and their role in tumor growth and metastasis. We will conclude with a brief discussion of therapy for pancreatic cancer and the potential role for immunotherapy. We hypothesize that the role of the immune system in tumor development and progression is tissue specific. Our hope is that better understanding of this process will lead to better treatments for this devastating disease.

Enhanced immunity against hepatoma induced by dendritic cells pulsed with Hsp70-H22 peptide complexes and CD40L

PURPOSE

Dendritic cell (DC)-based cancer vaccines have become an attractive antitumour therapeutic approach. However, clinical application of current DC-based cancer vaccines has been limited by their ineffectiveness. Heat shock protein 70 from Mycobacterium tuberculosis (TBhsp70) is known to have a potent adjuvant capability to induce maturation of DCs and thus acts as an alternative ligand to the CD40 ligand (CD40L) on T cells to induce a T-cell response. The aim of this study is to investigate whether the combination of TBhsp70-H22 tumour-peptide complexes and CD40L might improve the antitumour efficacy for development of therapeutic DC-based vaccines against hepatoma.

METHODS

The CD40, CD80, CD86 and HLA-DR expression on DCs pulsed with TBhsp70-H22 tumour-peptide complexes and soluble CD40L was studied by flow cytometric analysis, and T-helper type 1 cytokine secretion, such as IL-12p70 secretion, was tested by ELISA. The H22-specific cytotoxic T-lymphocytes (CTLs) were detected by a (51)Cr-release assay, and the in vivo antitumour immunity against hepatoma was measured by utilising H22-tumour-bearing mice after therapeutic administration.

RESULTS

Up-regulation of CD40, CD80, CD86 and HLA-DR expression on DCs pulsed with TBhsp70-H22 tumour-peptide complexes and CD40L was found, which stimulated a high level of T-helper type 1 cytokine secretion, such as IL-12p70, and resulted in the induction of H22-specific CTLs. The therapeutic administration of DCs pulsed in vitro with TBhsp70-H22 tumour-peptide complexes and CD40L significantly reduced the progression of H22 tumours in mice compared with DC-Hsp70-H22 peptide complexes or DC-CD40L alone.

CONCLUSIONS

Our findings demonstrate that DCs pulsed with Hsp70-H22-peptide complexes and CD40L enhance the antitumour immunity against hepatoma, which provides a novel immunotherapeutic approach against cancer.

The CD40-CD154 interaction would correlate with proliferation and immune escape in pancreatic ductal adenocarcinoma

BACKGROUND

CD40 and CD154 are associated with lymphocyte signaling pathways and they are also expressed in some malignant neoplasms, but the significance in pancreatic cancer is unknown.

METHODS

Eighty pancreatic cancer specimens were stained immunohistochemically, and the results were correlated with the patients' clinicopathologic features. Subsequently, in vitro analysis of CD40-CD154 signaling was performed.

RESULT

Immunohistochemical analysis of tumor cells showed that 29 patients (36.3%) were positive for CD40, and 17 patients (21.3%) had very high CD154 expression. The survival of patients who had very high CD154 expression was significantly better than that of others (P = 0.0198). Univariate and multivariate analysis revealed that very high CD154 expression in cancer cells was not an independent, favorable prognostic factor (risk ratio, 0.493; P = 0.0224). On in vitro proliferation assay, the growth of PK-45P and KP-4 cells was blocked by CD40 and CD154 blocking antibodies. Moreover, on in vitro cytokine assay, Th-2 cytokines from PK-45P and SUIT-2 were blocked by CD40 or CD154 blocking antibody.

CONCLUSION

These results suggest that the CD40-CD154 interaction would correlate with cell proliferation and secretion of cytokines in PDAC cells, and CD154 overexpression could be a favorable prognostic factor in PDAC patients.

Primary and malignant cholangiocytes undergo CD40 mediated Fas dependent apoptosis, but are insensitive to direct activation with exogenous Fas ligand

INTRODUCTION

Cholangiocarcinoma is a rare malignancy of the biliary tract, the incidence of which is rising, but the pathogenesis of which remains uncertain. No common genetic defects have been described but it is accepted that chronic inflammation is an important contributing factor. We have shown that primary human cholangiocyte and hepatocyte survival is tightly regulated via co-operative interactions between two tumour necrosis family (TNF) receptor family members; CD40 and Fas (CD95). Functional deficiency of CD154, the ligand for CD40, leads to a failure of clearance of biliary tract infections and a predisposition to cholangiocarcinoma implying a direct link between TNF receptor-mediated apoptosis and the development of cholangiocarcinoma.

AIMS

To determine whether malignant cholangiocytes display defects in CD40 mediated apoptosis. By comparing CD40 and Fas-mediated apoptosis and intracellular signalling in primary human cholangiocytes and three cholangiocyte cell lines.

RESULTS

Primary cholangiocytes and cholangiocyte cell lines were relatively insensitive to direct Fas-mediated killing with exogenous FasL when compared with Jurkat cells, which readily underwent Fas-mediated apoptosis, but were extremely sensitive to CD154 stimulation. The sensitivity of cells to CD40 activation was similar in magnitude in both primary and malignant cells and was STAT-3 and AP-1 dependent in both.

CONCLUSIONS

1) Both primary and malignant cholangiocytes are relatively resistant to Fas-mediated killing but show exquisite sensitivity to CD154, suggesting that the CD40 pathway is intact and fully functional in both primary and malignant cholangiocytes 2) The relative insensitivity of cholangiocytes to Fas activation demonstrates the importance of CD40 augmentation of Fas dependent death in these cells. Agonistic therapies which target CD40 and associated intracellular signalling pathways may be effective in promoting apoptosis of malignant cholangiocytes.

Recent advances in bacillus Calmette–Guerin immunotherapy in bladder cancer

The concept of using Mycobacterium for cancer treatment goes back to the 19th Century. Today, bacillus Calmette–Guerin (BCG) vaccine is a well-established treatment for human bladder cancer that is arguably superior to intravesical chemotherapy for superficial disease and is commonly used as the first-line adjuvant treatment. Much has been learnt about the effects of BCG on bladder cancer and the immune system, but deeper understanding is required in order to improve its efficacy further, to be able to reliably predict responders and ultimately to adapt this most successful form of cancer immunotherapy for the treatment of other malignancies. This article summarizes the current understanding of BCG cancer immunotherapy mechanisms and discusses possible future developments.

Direct inhibition of elastase activity by indole-3-carbinol triggers a CD40-TRAF regulatory cascade that disrupts NF-kappaB transcriptional activity in human breast cancer cells

Treatment of highly tumorigenic MDA-MB-231 human breast cancer cells with indole-3-carbinol (I3C) directly inhibited the extracellular elastase-dependent cleavage of membrane-associated CD40, a member of the tumor necrosis factor (TNF) receptor superfamily. CD40 signaling has been implicated in regulating cell survival, apoptosis, and proliferation, as well as in sensitizing breast cancer cells to chemotherapy, and is therefore an important potential target of novel breast cancer treatments. The I3C-dependent accumulation of full-length unprocessed CD40 protein caused a shift in CD40 signaling through TNF receptor-associated factors (TRAF), including the TRAF1/TRAF2 positive regulators and TRAF3 negative regulator of NF-kappaB transcription factor activity. Because TRAF1 is a transcriptional target gene of NF-kappaB, I3C disrupted a positive feedback loop involving these critical cell survival components. siRNA ablation of elastase expression mimicked the I3C inhibition of CD40 protein processing and G(1) cell cycle arrest, whereas siRNA knockdown of TRAF3 and the NF-kappaB inhibitor IkappaB prevented the I3C-induced cell cycle arrest. In contrast, siRNA knockdown of PTEN had no effect on the I3C control of NF-kappaB activity, showing the importance of CD40 signaling in regulating this transcription factor. Our study provides the first direct in vitro evidence that I3C directly inhibits the elastase-mediated proteolytic processing of CD40, which alters downstream signaling to disrupt NF-kappaB-induced cell survival and proliferative responses. Furthermore, we have established a new I3C-mediated antiproliferative cascade that has significant therapeutic potential for treatment of human cancers associated with high levels of elastase and its CD40 membrane substrate.

Anti-CD40 monoclonal antibody

Normal, bi-directional interactions between CD 40 and its natural ligand CD 154 (CD 40 ligand) are central to the generation of both T cell-dependent, humoral immune responses and cytotoxic T-cell responses. CD 40 is expressed on a broad range of hematological and epithelial malignancies. The development of monoclonal antibodies directed against CD 40 allows effective targeting of malignant cells through multiple mechanisms that include the recruitment of immune effector mechanisms such as complement-dependent cytotoxicity and antibody-dependent cellular cytotoxicity, direct anti-proliferative effects on neoplastic cells and, importantly, by the activation of tumor-targeted cellular cytotoxicity. This review provides the background to the early clinical trial data that are now beginning to emerge for this potentially exciting new treatment approach.

Molecular mechanism and function of CD40/CD40L engagement in the immune system

SUMMARY

During the generation of a successful adaptive immune response, multiple molecular signals are required. A primary signal is the binding of cognate antigen to an antigen receptor expressed by T and B lymphocytes. Multiple secondary signals involve the engagement of costimulatory molecules expressed by T and B lymphocytes with their respective ligands. Because of its essential role in immunity, one of the best characterized of the costimulatory molecules is the receptor CD40. This receptor, a member of the tumor necrosis factor receptor family, is expressed by B cells, professional antigen-presenting cells, as well as non-immune cells and tumors. CD40 binds its ligand CD40L, which is transiently expressed on T cells and other non-immune cells under inflammatory conditions. A wide spectrum of molecular and cellular processes is regulated by CD40 engagement including the initiation and progression of cellular and humoral adaptive immunity. In this review, we describe the downstream signaling pathways initiated by CD40 and overview how CD40 engagement or antagonism modulates humoral and cellular immunity. Lastly, we discuss the role of CD40 as a target in harnessing anti-tumor immunity. This review underscores the essential role CD40 plays in adaptive immunity.

Involvement of CD40 targeting miR-224 and miR-486 on the progression of pancreatic ductal adenocarcinomas

BACKGROUND

Genetic and epigenetic alterations during development of pancreatic ductal adenocarcinomas (PDAC) are well known. Genetic and epigenetic data were correlated with tumor biology to find specific alterations responsible for invasion and metastasis in pancreatic ductal adenocarcinomas.

METHODS

A total of 16 human PDAC cell lines were used in murine orthotopic PDAC models. By means of standardized dissemination scores, local invasion and metastatic spread were assessed. mRNA and microRNA expression were studied by microarray and TaqMan low-density array. Quantitative real-time-polymerase chain reaction and flow cytometry were used for expression validation.

RESULTS

CD40 was detected as a relevant target gene for differentially expressed miRNAs observed in highly invasive and metastatic PDAC only. A significant overexpression (P < .05) of CD40-related miRNAs miR-224 and miR-486 was detected in highly invasive and metastatic PDAC, whereas CD40 mRNA expression was not significantly altered. Instead, CD40 protein expression at cell surfaces of these highly invasive and metastatic PDAC was significantly reduced (P < .01).

CONCLUSIONS

Epigenetic alterations with upregulated CD40-targeting miR-224 and miR-486 are related to downregulated CD40 protein expression at cell surfaces in highly invasive and metastatic PDAC. Thus, miRNA-regulated CD40 expression seems to play an important role in progression of PDAC. These data suggest a diagnostic and therapeutic potential for CD40 and/or its targeting miRNAs in PDAC.

Therapeutic interventions targeting CD40L (CD154) and CD40: the opportunities and challenges

CD40 was originally identified as a receptor on B-cells that delivers contact-dependent T helper signals to B-cells through interaction with CD40 ligand (CD40L, CD154). The pivotal role played by CD40-CD40L interaction is illustrated by the defects in B-lineage cell development and the altered structures of secondary lymphoid tissues in patients and engineered mice deficient in CD40 or CD40L. CD40 signaling also provides critical functions in stimulating antigen presentation, priming of helper and cytotoxic T-cells and a variety of inflammatory reactions. As such, dysregulations in the CD40-CD40L costimulation pathway are prominently featured in human diseases ranging from inflammatory conditions to systemic autoimmunity and tissue-specific autoimmune diseases. Moreover, studies in CD40-expressing cancers have provided convincing evidence that the CD40-CD40L pathway regulates survival of neoplastic cells as well as presentation of tumor-associated antigens to the immune system. Extensive research has been devoted to explore CD40 and CD40L as drug targets. A number of anti-CD40L and anti-CD40 antibodies with diverse biological effects are in clinical development for treatment of cancer and autoimmune diseases. This chapter reviews the role of CD40-CD40L costimulation in disease pathogenesis, the characteristics of therapeutic agents targeting this pathway and status of their clinical development.

Complete rejection of a T-cell lymphoma due to synergism of T-cell receptor costimulatory molecules, CD80, CD40L, and CD40

The equal importance of the qualitative and quantitative characteristics of antigen presentation as well as the set of costimulatory signals provided by antigen presenting cells to T-cells in determining the outcome of T-cell responses at the time of antigen recognition is now clear. Moreover, an important function in innate mechanisms has been recently attributed to costimulatory molecules demonstrating their relevant role in different stages of immune response. In this paper, we demonstrated the ability of CD40L (CD154) and CD80 costimulatory molecules expression in a T-cell lymphoma to induce both T-cell dependent and independent immune responses leading to an important anti-tumor effect. CD40 expression by LBC cells enhanced only T-cell dependent anti-tumor immune response resulting in tumor rejection. Furthermore, this work represents the first report to describe complete tumor rejection after co-inoculation of lymphoma cells transfected with CD40L and CD80 in either presence or absence of CD40 expressing lymphoma cells. In addition, this synergistic effect resulted in long lasting immunity to parental tumor cells. Co-inoculation of tumor cells each genetically modified to express a different costimulatory molecule circumvents the need to co-transfect genetically unstable tumor cells and represents an option for those weakly or non-immunogenic tumors where either treatment alone proved to be inefficient. This strategy represents a promising approach for inducing anti-tumor immunity and provides a new rational design of cancer therapies.

CD40-mediated death and cytokine secretion in colorectal cancer: a potential target for inflammatory tumour cell killing

CD40, a member of the tumour necrosis factor family, is expressed in a variety of epithelial cells. Although soluble CD40 agonists are growth-inhibitory, membrane-presented CD40 ligand (CD40L) induces extensive apoptosis in carcinoma cells. This study investigated whether CD40 is expressed in human colorectal carcinoma (CRC) cells and explored the functional consequences of CD40 ligation. CD40 expression in a panel of CRC lines was assessed by flow cytometry and in resected human CRCs by immunohistochemistry. CRC cells were treated in vitro with soluble CD40 agonists or cocultured with fibroblasts expressing membrane-bound CD40 ligand. Apoptosis was determined by flow cytometry using Annexin V/propidium iodide labelling and by a DNA fragmentation assay. Cytokine secretion induced by CD40 ligation was quantified by a multiplex-bead array approach. We show that CD40 is expressed in a proportion of established CRC lines in culture and that receptor expression is functional. Activation of CD40 by membrane-presented CD40L, but not soluble agonists, causes high levels of death in CD40-positive CRC cells and induces secretion of proinflammatory cytokines. In agreement with our in vitro observations, immunohistochemical studies demonstrated that CD40 is highly expressed in a proportion of colorectal cancer specimens. The high level of susceptibility of CRC cells to CD40-killing combined with the ability of CD40 to induce concomitant secretion of proinflammatory cytokines suggest that CD40 ligation may represent a novel mechanism for elimination of CRC cells and render CD40 a promising therapeutic target for the eradication of colorectal tumours.

Effects of CD40 binding on ovarian carcinoma cell growth and cytokine production in vitro

The poor prognosis associated with ovarian carcinoma (OVCA) is linked to the high incidence of local recurrence. There is a pressing need to identify factors that can play a role in OVCA growth and spread. Here, we focused on CD40, a member of the tumour necrosis factor (TNF) receptor superfamily with important functions in immune response. The expression of CD40 has been reported on various types of carcinoma cells, but its biological role is still poorly understood. The aim of the present study was to investigate the expression and function of the CD40 in OVCA cell lines. Detectable CD40 levels ranging from low to very high were found on the cell surface of several OVCA cell lines by flow cytometry analysis. Co-culture with a murine cell line transfected with CD40 ligand (CD40L) inhibited cell growth and up-regulated the secretion of proinflammatory cytokines interleukin (IL)-6, IL-8 and TNF-alpha in high-level CD40-expressing OVCA cell lines. Similarly, an increase of IL-6 and IL-8 release could be obtained by adding a soluble form of CD40L to the OVCA cultures. These results suggest that CD40-CD40L interaction is an important pathway affecting growth regulation and cytokine production in OVCA.

Differential CD40/CD40L Expression Results in Counteracting Antitumor Immune Responses

Establishment of host-protective memory T cells against tumors is the objective of an antitumor immunoprophylactic strategy such as reinforcing T cell costimulation via CD40-CD40L interaction. Previous CD40-targeted strategies assumed that T cell costimulation is an all-or-none phenomenon. It was unknown whether different levels of CD40L expression induce quantitatively and qualitatively different effector T cell responses. Using mice expressing different levels of CD40L, we demonstrated that the greater the T cell CD40L expression the less tumor growth occurred; the antitumor T cell response was host-protective. Lower levels of CD40L expression on T cells induced IL-10-mediated suppression of tumor-regressing effector CD8(+) T cells and higher productions of IL-4 and IL-10. Using mice expressing different levels of CD40 or by administering different doses of anti-CD40 Ab, similar observations were recorded implying that the induction of protumor or antitumor T cell responses was a function of the extent of CD40 cross-linking. IL-10 neutralization during priming with tumor Ags resulted in a stronger tumor-regressing effector T cell response. Using IL-10(-/-) DC for priming of mice expressing different levels of CD40L and subsequent transfer of the T cells from the primed mice to nu/nu mice, we demonstrated the protumor role of IL-10 in the induction of tumor-promoting T cells. Our results demonstrate that a dose-dependent cross-linking of a costimulatory molecule dictates the functional phenotype of the elicited effector T cell response. The T cell costimulation is a continuum of a function that induces not only graded T cell responses but also two counteracting responses at two extremes.

CD40 signaling predicts response to preoperative trastuzumab and concomitant paclitaxel followed by 5-fluorouracil, epirubicin, and cyclophosphamide in HER-2-overexpressing breast cancer

INTRODUCTION

We performed gene expression analysis to identify molecular predictors of resistance to preoperative concomitant trastuzumab and paclitaxel followed by 5-fluorouracil, epirubicin, and cyclophosphamide (T/FEC).

METHODS

Pretreatment fine-needle aspiration specimens from 45 patients with HER-2-overexpressing stage II to IIIA breast cancer were subjected to transcriptional profiling and examined for differential expression of various genes and gene sets. The primary endpoint for tumor response was pathologic complete response (pCR). Correlations between pCR and gene expression were sought.

RESULTS

The overall pCR rate was 64%. Age, nuclear grade, tumor size, nodal status, quantitative expression of estrogen and HER-2 receptor mRNA, and HER-2 gene copy number showed no correlation with pCR. Results of gene set enrichment analysis suggested that the lower expression of genes involved with CD40 signaling is associated with a greater risk of residual cancer after the preoperative chemotherapy that includes trastuzumab.

CONCLUSION

CD40 signaling may play a role in determining response to trastuzumab-plus-T/FEC therapy in patients with HER-2-overexpressing breast cancer.

Functional Dichotomy in CD40 Reciprocally Regulates Effector T Cell Functions

Activation of T cells requires signals through Ag-specific TCR and costimulatory molecules such as CD40L. Although the use of defined tumor Ags for the induction of protective T cells met with limited success, the CD40-CD40L interaction that was proposed to induce antitumor T cells did not prevent tumor growth completely. Using a model for prostate tumor, a leading cause of tumor-induced mortality in men, we show that the failure is due to a novel functional dichotomy of CD40 whereby it self-limits its antitumor functions by inducing IL-10. IL-10 prevents the CD40-induced CTL and TNF-alpha and IL-12 production, Th1 skewing, and tumor regression. Priming mice with tumor lysate-pulsed IL-10-deficient dendritic cells (DCs) or wild-type DC plus anti-IL-10 Ab establishes antitumor memory T cells that can transfer the protection into syngenic nude mice. Infusion of Ag-pulsed IL-10-deficient but not wild-type DCs back into syngenic mice results in successful therapeutic autovaccination. Thus, we demonstrate the IL-10-sensitive antitumor T cell memory formulating a novel prophylactic and therapeutic principle.

Innate Immunity in Multiple Sclerosis: Myeloid Dendritic Cells in Secondary Progressive Multiple Sclerosis Are Activated and Drive a Proinflammatory Immune Response

Multiple sclerosis (MS) is postulated to be a T cell-mediated autoimmune disease characterized clinically by a relapsing-remitting (RR) stage followed by a secondary progressive (SP) phase. The progressive phase is felt to be secondary to neuronal degenerative changes triggered by inflammation. The status of the innate immune system and its relationship to the stages of MS is not well understood. Dendritic cells (DCs) are professional APCs that are central cells of the innate immune system and have the unique capacity to induce primary immune responses. We investigated circulating myeloid DCs isolated directly from the blood to determine whether there were abnormalities in myeloid DCs in MS and whether they were related to disease stage. We found that SP-MS subjects had an increased percentage of DCs expressing CD80, a decreased percentage expressing PD-L1, and an increased percentage producing IL-12 and TNF-alpha compared with RR-MS or controls. A higher percentage of DCs from both RR and SP-MS patients expressed CD40 compared with controls. We then investigated the polarization effect of DCs from MS patients on naive T cells taken from cord blood using a MLR assay. Whereas DCs from RR-MS induced higher levels of Th1 (IFN-gamma, TNF-alpha) and Th2 (IL-4, IL-13) cytokines compared with controls, DCs from SP-MS only induced a polarized Th1 response. These results demonstrate abnormalities of DCs in MS and may explain the immunologic basis for the different stages and clinical patterns of MS.

Stimulation through CD40 on Mouse and Human Renal Cell Carcinomas Triggers Cytokine Production, Leukocyte Recruitment, and Antitumor Responses that Can Be Independent of Host CD40 Expression

CD40, a member of the TNFR superfamily, is expressed on a variety of host immune cells, as well as some tumors. In this study, we show that stimulation of CD40 expressed on both mouse and human renal carcinoma cells (RCCs) triggers biological effects in vitro and in vivo. Treatment of the CD40+ Renca mouse RCC tumor cells in vitro with an agonistic anti-CD40 Ab induced strong expression of the genes and proteins for GM-CSF and MCP-1, and induced potent chemotactic activity. Similarly, administration of alphaCD40 to both wild-type and CD40-/- mice bearing Renca tumors resulted in substantial amounts of TNF-alpha and MCP-1 in the serum, increased the number of total splenocytes and MHC class II+ CD11c+ leukocytes, and when combined with IFN-gamma, inhibited the progression of established Renca tumors in vivo in both wild-type and CD40-/- mice. Similarly, treatment of CD40+ A704 and ACHN human RCC lines with mouse anti-human CD40 Ab induced strong expression of genes and proteins for MCP-1, IL-8, and GM-CSF in vitro and in vivo. Finally, in SCID mice, the numbers of ACHN pulmonary metastases were dramatically reduced by treatment with species-specific human CD40 Ab. These results show that CD40 stimulation of CD40+ tumor cells can enhance immune responses and result in antitumor activity.

Construction and expression of a eukaryotic expression plasmid containing human CD40 ligand in human hepatocellular carcinoma cell line HepG2 and its effect on apoptosis

AIM: To construct and express a eukaryotic expression plasmid containing human CD40 ligand (CD40L) in human hepatocellular carcinoma cell line HepG2 for the biological function study of CD40L on HepG2 cells.

METHODS: Human CD40L cDNA was synthesized by reverse transcription-polymerase chain reaction (RT-PCR) with the specific primers from the RNA of human peripheral blood monocyte (PBMC) and directly ligated into the eukaryotic expression vector pcDNA^TM3.1/myc-His(-)A through digestion with specific restriction endonuclease. The recombined plasmid was transformed into the E. coli DH5α to amplify CD40L gene. Then HepG2 cells were divided into 4 groups. The cells in group A were transfected with the recombined plasmid, and group B with the blank plasmid (not containing CD40L cDNA). The cells in group C were just normally cultured, and the ones in group D weren't transfected but added G418 as the control for transfection. The expression of CD40L and CD40 were detected by RT-PCR and fluorescent activated cell sorter (FACS) in HepG2 cells, and the apoptosis, cell cycle, as well as Fas expression, were measured by FACS.

RESULTS: The full-length human CD40L cDNA was successfully cloned into the eukaryotic vector pcDNA^TM3.1/myc-His(-)A. The recombinant plasmid was stably transfected into group A and the rate of CD40L expression was 39.7%. There was no CD40L expression in group B and C. The rates of CD40 expression in group A, B and C were 15.4%, 31.7% and 28.5%, respectively. The apoptotic rate of group A was 45.0±0.3%, but neither group B or C showed obvious apoptosis (P <0.01). Compared with group C, a larger proportion of cells in group A was restrained at G0/G1 phase (90.4±1.3% vs 60.6±1.5%, P <0.01), while the proportions of the cells in S phase (6.32±1.0% vs 12.0±0.7%) and G2/M phase (3.3±0.7% vs 27.3±1.2%) were reduced (both P <0.01). The expression of Fas in group A showed marked increase as compared with that in group B and C (27.8±1.5% vs 3.2±0.8%, 4.2±1.0%, respectively, both P <0.01).

CONCLUSION: The eukaryotic expression plasmid pcDNA^TM3.1/myc-His(-)A can be stably expressed in HepG2 cell line. CD40L-induced apoptosis of HepG2 is correlated with the increased expression of Fas and cell cycle arrest.