Antibodies to EGF Receptor Family Members Can Upregulate Tumor Immunity.

Immunologic mechanisms influence how a cancer patient responds to therapy. Monoclonal antibodies (mAbs) to the epidermal growth factor receptor are clinically approved, and a lung cancer vaccine inducing antibodies to epidermal growth factor (EGF) has some beneficial clinical effects. We tested the hypothesis that mAbs to epidermal growth factor receptor, EGF, and tumor growth factor alpha (TGF-α), in addition to any other effects, can facilitate the generation of a tumor-destructive immunologic response.

From the Hellstrom paradox toward cancer cure.

Several decades ago we published some of the first papers showing that both murine and human cancers are recognized in vitro as immunologically foreign and that this is the case also in the presence of a growing tumor. The latter situation, sometimes referred to as the Hellstrom paradox, implies that the tumor is protected in vivo by a highly immunosuppressive environment. After many disappointments, the discovery that tumor-related immunosuppression can be counteracted by administrating monoclonal antibodies (mAbs) to checkpoint inhibitors such as CTLA-4, PD-1, and PD-L1 is now revolutionizing cancer therapy.

Ovarian carcinomas express HE4 epitopes independently of each other.

Background: The gene encoding HE4 undergoes alternative splicing to yield multiple protein isoforms. We investigated anti-HE4 mAbs which recognize epitopes on the C (2H5 and 3D8) or N (12A2 and 14E2) terminals.

Methods: A Luminex assay was applied to determine mAb affinity.

Tumor Regression and Cure Depends on Sustained Th1 Responses.

While immunomodulatory monoclonal antibodies (mAbs) have therapeutic efficacy against many tumors, few patients are cured. Attempting to improve their therapeutic efficacy we have applied the TC1 mouse lung carcinoma model and injected established subcutaneous tumors intratumorally with 3 weekly doses of various combinations of mAbs. Combinations of mAbs to CTLA4/PD1/CD137 (the 3 mAb combination) and to CTLA4/PD1/CD137/CD19 (the 4 mAb combination) were most efficacious to induce complete regression of both the injected tumor and an untreated tumor in the same mouse.

Curing tumor-bearing mice by shifting a Th2 to a Th1 anti-tumor response.

Over the past several years remarkable therapeutic responses have been obtained with immunomodulatory monoclonal antibodies (mAbs), both in mice \cite{10,18,20,48,54,61} and human cancer patients \cite{1,3,14,28,30,39,80}. However, complete regressions and cures are infrequent and not predictable and some tumor types respond much worse than others. As an attempt to increase curability, we have investigated in mouse models the therapeutic efficacy of several mAb combinations, focusing on anti-PD-1/CTLA-4/CD137 and anti-PD-1/CTLA-4/CD137/CD19, and we have also combined mAbs with the chemotherapeutic drug cisplatin.

Selenium-Binding Protein 1 (SBP1) autoantibodies in ovarian disorders and ovarian cancer.

Infertility is a risk factor for ovarian cancer (OvCa). The goal was to determine if antibodies to selenium-binding protein 1 (SBP1), an autoantibody we identified in patients with premature ovarian failure (POF), occurs in both infertility and OvCa patients, and thus could be associated with preneoplasia. Anti-SBP1 was measured by immunoassay against recombinant SBP1, in sera from OvCa (n = 41), infertility (n = 92) and control (n = 87) patients.

An In Vitro Model That Predicts the Therapeutic Efficacy of Immunomodulatory Antibodies.

Immunomodulatory monoclonal antibodies (mAbs) have efficacy in patients with advanced cancer and are the focus of intensive research. However, cures are infrequent and responses vary among tumor types and among subjects with the same tumor. An in vitro test would be valuable to determine the most effective mAb combination for a given case and to evaluate novel agents.

Immune Mechanisms Are Major Players in Cancer.

Vaccination with sipuleucel-T produced IgG antibodies to secondary prostatic carcinoma antigens and prolonged survival in some patients, and assaying for antibodies may provide prognostic information and identify new vaccine targets. Additional approaches to improve T-cell responses are needed to improve the clinical efficacy. See related article by GuhaThakurta et al.

Detection of the HE4 protein in urine as a biomarker for ovarian neoplasms: Clinical correlates.

Objectives: To measure HE4 levels in urine from normal donors, patients with LMP tumors and ovarian cancer patients and to correlate levels with clinical factors in ovarian cancer patients.

Methods: Archived samples from controls, patients with LMP tumors and ovarian cancer were tested using commercial assays, including serially collected serum and urine samples from women treated for stage III/IV serous ovarian cancer.

Results: Five of 6 patients with stage I/II and 26 of 36 stage III/IV serous ovarian cancer patients had HE4-positive urines, similar to serum samples (4 of 5 stage I/II and 26 of 34 stage III/IV) when tested at the same level of specificity (95%).

Curing mice with large tumors by locally delivering combinations of immunomodulatory antibodies.

Purpose: Immunomodulatory mAbs can treat cancer, but cures are rare except for small tumors. Our objective was to explore whether the therapeutic window increases by combining mAbs with different modes of action and injecting them into tumors.

Experimental Design: Combinations of mAbs to CD137/PD-1/CTLA-4 or CD137/PD-1/CTLA-4/CD19 were administrated intratumorally to mice with syngeneic tumors (B16 and SW1 melanoma, TC1 lung carcinoma), including tumors with a mean surface of approximately 80 mm(2).

Dual targeting of CD137 co-stimulatory and PD-1 co-inhibitory molecules for ovarian cancer immunotherapy.

We recently demonstrated that simultaneous targeting of CD137 co-stimulatory and programmed cell death 1 (PD-1) co-inhibitory molecules synergistically induced an anticancer immune response in the ID8 syngeneic orthotopic mouse ovarian carcinoma model. We further showed that the therapeutic efficacy was enhanced by treatment with cisplatin. These findings provide a rationale for evaluating dual targeting of CD137/PD-1 co-signaling molecules in ovarian cancer patients.

Human and mouse CD137 have predominantly different binding CRDs to their respective ligands.

Monoclonal antibodies (mAbs) to CD137 (a.k.a.

Combinatorial PD-1 blockade and CD137 activation has therapeutic efficacy in murine cancer models and synergizes with cisplatin.

There is an urgent need for improved therapy for advanced ovarian carcinoma, which may be met by administering immune-modulatory monoclonal antibodies (mAbs) to generate a tumor-destructive immune response. Using the ID8 mouse ovarian cancer model, we investigated the therapeutic efficacy of various mAb combinations in mice with intraperitoneal (i.p.

Anti-HE4 antibodies in infertile women and women with ovarian cancer.

Objectives: To develop an assay for anti-HE4 antibodies and assess such antibodies in sera from women with increased epidemiologic risk for ovarian cancer (infertility) and patients with ovarian cancer in comparison to controls.

Methods: An ELISA was developed to measure antibodies to recombinant full length HE4 and cut-off values were determined for different levels of specificity (up to 99%).

Results: Infertile women more frequently had anti-HE4 antibodies than controls (23% at 98% specificity, p < 0.

Long-lasting complete regression of established mouse tumors by counteracting Th2 inflammation.

Mice with intraperitoneal ID8 ovarian carcinoma or subcutaneous SW1 melanoma were injected with monoclonal antibodies (mAbs) to CD137PD-1CTLA4 7-15 days after tumor initiation. Survival of mice with ID8 tumors tripled and >40% of mice with SW1 tumors remained healthy >150 days after last treatment and are probably cured. Therapeutic efficacy was associated with a systemic immune response with memory and antigen specificity, required CD4 cells and involved CD8 cells and NK cells to a less extent.

Th2 type inflammation promotes the gradual progression of HPV-infected cervical cells to cervical carcinoma.

Objectives: To investigate the role of immunological parameters in tumorigenesis of cervical cancer in women infected with high risk human papillomavirus (hr-HPV), and determine whether key findings with human material can be recapitulated in the mouse TC1 carcinoma model which expresses hr-HPV epitopes.

Methods: Epithelial and lymphoid cells in cervical tissues were analyzed by immunohistochemistry and serum IL10 levels were determined by ELISA. Tumor draining lymph nodes were analyzed in the mouse TC1 model by flow cytometry.

Elafin selectively regulates the sensitivity of ovarian cancer cells to genotoxic drug-induced apoptosis.

Objective: Elafin has been reported to be abundantly expressed in human epithelial ovarian carcinoma (EOC), however, its functions are poorly understood. Here, we evaluated the role of elafin in modulating the sensitivity of human EOC cells to chemotherapeutic drugs.

Methods: Elafin expression was determined by ELISA in 9 established human EOC cell lines.

Silencing of the TGF-β1 gene increases the immunogenicity of cells from human ovarian carcinoma.

Cells from many tumors produce transforming growth factor (TGF)-β which facilitates their escape from control by the immune system. We previously reported that nonimmunogenic cells from either of 2 transplantable mouse tumors became effective as therapeutic tumor vaccines after lentivirus-mediated shRNA interference to "silence" the TGF-β1 gene. We now show that cells from in vitro cultured human ovarian carcinomas (OvC) make large amounts of TGF-β1 and that this can be prevented by "silencing" the TGF-β1 gene.

Evaluation of ovarian cancer remission markers HE4, MMP7 and Mesothelin by comparison to the established marker CA125.

Objective: Evaluate and compare the effectiveness of CA125, HE4, Mesothelin and MMP7 marker levels to monitor ovarian cancer patients after surgery and chemotherapy. Evaluate the lead time of a rise of marker levels before recurrence.

Methods: The study consists of 23 patients with advanced stage ovarian/fallopian tube cancer.

Autoantibodies to mesothelin in infertility.

Background: According to extensive epidemiologic data, infertility is associated with increased ovarian cancer risk. Previous studies showed that both women with infertility and those with ovarian cancer have autoantibodies to ovarian antigens. The objective was to determine if women with infertility have antibodies to mesothelin, a well-characterized ovarian cancer antigen.

The hen model of human ovarian cancer develops anti-mesothelin autoantibodies in response to mesothelin expressing tumors.

Objective: Study of the hen immune system led to seminal contributions to basic immunological principles. Recent studies of spontaneous ovarian cancer in the laying hen show strikingly similar tumor types and antigen expression compared to human ovarian cancer, suggesting hens would be valuable for studies of tumor immunology and pre-clinical vaccine development. Circulating mesothelin is a relatively specific marker for human ovarian cancer and autoantibodies to mesothelin were reported.

fTwo novel biomarkers, mesothelin and HE4, for diagnosis of ovarian carcinoma.

INTRODUCTION: There is a need to improve the diagnosis and prognosis of ovarian carcinoma, particularly the serous type of cancer. Mesothelin and HE4 are two novel biomarkers which are expressed in serous ovarian carcinoma and can be measured in serum and other body fluids, including urine, by using ELISA. The measurement of antibodies to these markers can provide additional useful information.

Local release of highly loaded antibodies from functionalized nanoporous support for cancer immunotherapy.

We report that antibodies can be spontaneously loaded in functionalized mesoporous silica (FMS) with superhigh density (0.4-0.8 mg of antibody/mg of FMS) due to their comprehensive noncovalent interaction.

Detection of the HE4 protein in urine as a biomarker for ovarian neoplasms.

The HE4 protein is overexpressed in ovarian carcinomas and can be detected in serum by an ELISA with sensitivity similar to CA125 and higher specificity for malignant disease. We now demonstrate that HE4 can also be detected in the urine at a specificity level of 94.4%, including 13/15 (86.

Administration of cyclophosphamide changes the immune profile of tumor-bearing mice.

Cyclophosphamide (CTX) is often used to create a "window" for more effective therapeutic tumor vaccination. According to a commonly applied protocol, we injected 2 mg CTX intraperitoneally to mice with small (2 to 3 mm diameter) or large (5 to 7 mm, and in one experiment 8 to 10 mm diameter) subcutaneously growing tumors from the SW1 clone of the K1735 melanoma, euthanized the mice 4 days later and studied the composition of lymphoid cells by flow cytometry in both spleens and tumors. Administration of CTX increased the percentage of CD3, CD4, and CD8 cells with the increase in tumors being significantly greater than in spleens, and it also increased the percentage of B cells in spleens and tumors.