Ovarian cancer cytoreduction induces changes in T cell population subsets reducing immunosuppression

Immunity of human epithelial ovarian carcinoma: the paradigm of immune suppression in cancer

Epithelial ovarian cancer (EOC) is a significant cause of cancer-related mortality in women, and there has been no substantial decrease in the death rates due to EOC in the last three decades. Thus, basic knowledge regarding ovarian tumor cell biology is urgently needed to allow the development of innovative treatments for EOC. Traditionally, EOC has not been considered an immunogenic tumor, but there is evidence of an immune response to EOC in patients. Clinical data demonstrate that an antitumor immune response and immune evasion mechanisms are correlated with a better and lower survival, respectively, providing evidence for the immunoediting hypothesis in EOC. This review focuses on the immune response and immune suppression in EOC. The immunological roles of chemotherapy and surgery in EOC are also described. Finally, we detail pilot data supporting the efficiency of immunotherapy in the treatment of EOC and the emerging concept that immunomodulation aimed at counteracting the immunosuppressive microenvironment must be associated with immunotherapy strategies.

Glycodelin A is a prognostic marker to predict poor outcome in advanced stage ovarian cancer patients

BACKGROUND

Glycodelin is a cell surface glycoprotein offering a unique gender specific carbohydrate configuration. Sialylated carbohydrate structures, which are unusual for mammals, characterize Glycodelin isolated from amniotic fluid (Glycodelin A, GdA). Glycodelin in general exerts multiple, partly opposing functions ranging from immunosuppression to cell differentiation. As these markedly influence tumorigenesis, this study aimed to clarify whether expression of different Glycodelin isoforms is related to clinicopathological characteristics and prognosis of ovarian cancer patients. Further the use of Glycodelin as a serum marker in benign and malignant ovarian diseases was evaluated.

METHODS

Ovarian cancer specimens (n = 152) were stained for Glycodelin with carbohydrate and peptide specific antibodies. Associations between Glycodelin expression and histological grading, FIGO stage as well as patient's prognosis were examined. Glycodelin was correlated to expression of gonadotropin receptors and mucin-1, which are discussed as ovarian cancer tissue markers. In addition, Glycodelin serum concentrations were analyzed in patients suffering from benign (n = 73) or malignant (n = 38) ovarian neoplasias.

RESULTS

Glycodelin A was found to be an independent prognostic marker for poor prognosis in advanced ovarian cancer patients. GdA staining correlated with gonadotropin receptor (FSHR and LHCGR) and with hCG expression. Gd expression showed a positive correlation with a tumour-associated epitope of mucin 1 (TA-MUC1). Further, compared to ovarian cancer, serum Gd was increased in patients with benign ovarian tumors.

CONCLUSION

Glycodelin A might be related to tumor aggressiveness and poor clinical outcome in advanced epithelial ovarian cancer. Glycodelin serum levels found in patients suffering from benign ovarian tumors, might contribute to a more global attenuation during progression of these precursor lesions.

Inflammation and ovarian cancer

Epithelial ovarian cancer (EOC) is a highly lethal gynecological cancer for which overall prognosis has remained poor over the past few decades. A number of theories have been postulated in an effort to explain the etiology of EOC. Noteworthy, these theories likely are not mutually exclusive, as they all converge more or less on the role of inflammation in promoting ovarian tumorigenesis and cancer progression. The tumor milieu in which ovarian carcinoma develops has been described as one enriched with a broad spectrum of pro-inflammatory cytokines and chemokines. In particular, several of these cytokines, such as tumor necrosis factor (TNF)-α, interleukin (IL)-1β and IL-6, produced by tumor itself or/and activated immune cells, besides stimulating cancer cell growth, have been shown to influence clinical disease status and prognosis, by reducing responsiveness to chemotherapy and inducing symptoms such as anorexia, altered energy metabolism, anemia, weight loss, depression and fatigue. Recent data show that cytokine antagonists may have a role to play in the treatment of ovarian cancer. Their action by inhibiting both production and activity of inflammatory cytokines seems to obtain the control of angiogenetic and apoptotic events, the reversal of chemoresistance, the improvement of systemic symptoms and prognosis. In the light of our scientific research and the most recent experimental and clinical advances, our review will discuss the most relevant and recent findings on the role of proinflammatory cytokines in the pathogenesis and prognosis of ovarian cancer and the possible therapeutic implications.

Monoclonal antibodies in gynecological cancer: a critical point of view

During the last decades, several improvements in treating gynecological malignancies have been achieved. In particular, target therapies, mostly monoclonal antibodies, have emerged as an attractive option for the treatment of these malignancies. In fact, various molecular-targeted agents have been developed for a variety of malignancies with the objective to interfere with a precise tumor associated receptor, essential for cancer cell survival or proliferation, blocking its function, of the cancer cells. Alternatively, monoclonal antibodies have been developed to block immune suppression or enhance functions of immune effector cells. So far, several monoclonal antibodies have been tested for clinical efficacy for the treatment of gynecological cancers. Antibodies against Vascular Endothelial Growth Factor (VEGF) and Epidermal Growth Factor Receptor (EGFR) have been used in different neoplasms such as ovarian and cervical cancer. Catumazumab, a bivalent antibody against CD3 and EpCAM, is effective in the treatment of neoplastic ascites. Other antibodies are peculiar for specific cancer-associated antigen such as Oregovomab against CA125 or Farletuzumab against the folate receptor. Here we describe the preclinical and clinical experience gained up to now with monoclonal antibodies in tumors of the female genital tract and trace future therapeutic and research venues.

Thinking twice before abandoning first-line chemotherapy in ovarian cancer: report of two cases and literature review. Passing from tri-weekly to weekly regimens

We present two cases of advanced ovarian cancer treated with neoadjuvant chemotherapy with standard tri-weekly carboplatin and paclitaxel. Therapy was converted to weekly regimens because of disease progression, resulting in disease response. Weekly regimens could overcome drug resistance and this strategy should be attempted before abandoning first-line chemotherapy in favor of palliation.

HER2-based recombinant immunogen to target DCs through FcγRs for cancer immunotherapy

Dendritic cell (DC)-based immunotherapy is an attractive approach to induce long lasting antitumor effector cells aiming to control cancer progression. DC targeting is a critical step in the design of DC vaccines in order to optimize delivery and processing of the antigen, and several receptors have been characterized for this purpose. In this study, we employed the FcγRs to target DCs both in vitro and in vivo. We designed a recombinant molecule (HER2-Fc) composed of the immunogenic sequence of the human tumor-associated antigen HER2 (aa 364–391) and the Fc domain of a human IgG₁. In a mouse model, HER2-Fc cDNA vaccination activated significant T cell-mediated immune responses towards HER2 peptide epitopes as detected by IFN-γ ELIspot and induced longer tumor latency as compared to Ctrl-Fc-vaccinated control mice. Human in vitro studies indicated that the recombinant HER2-Fc immunogen efficiently targeted human DCs through the FcγRs resulting in protein cross-processing and in the activation of autologous HER2-specific CD8⁺ T cells from breast cancer patients.

Immune effects of trastuzumab

Trastuzumab's targeted therapy has become a stronghold for human epidermal growth factor receptor 2 positive breast cancer patients. This humanized monoclonal antibody binds to the extracellular juxta-membrane domain of HER2 and inhibits the proliferation and survival of HER2 dependent cancer cells. The ways by which this molecule exerts its action have been partially elucidated but several new mechanisms are being constantly identified. Several new agents are being introduced that interfere with HER2. Several new immunotherapy strategies are being introduced in order to direct the immune system against cells and tissues that aberrantly overexpressed HER2. We review the strategies currently adopted and those suggested against HER2 expressing tumors.

Ovarian cancer creates a suppressive microenvironment to escape immune elimination

BACKGROUND

Considering the high mortality rate of ovarian cancer due to the absence of curative treatment in advanced stage or at recurrence, new therapeutic strategies are urgently needed. Immunotherapy is one of these strategies that yielded promising results in fundamental and animal research in the past years. However, implementation in clinical practice remains poor. The aim of this review is to gain insight into the mechanisms of interaction between ovarian cancer and the immune system in order to develop better immunotherapeutic strategies.

METHODS

We searched the published literature for studies focusing on interactions between ovarian cancer and the immune system, with emphasis on outcome data in order to create a knowledge base that is well grounded in clinical reality.

RESULTS

The immunological response against cancer is a critical balance between immune-activating and immune-suppressing mechanisms. Besides the immune-activating tumor infiltrating lymphocytes (TILs), immune-suppressive regulatory T-cells (Tregs), tolerance-inducing plasmacytoid dendritic cells (pDCs), B7-H4+ macrophages, immune-suppressive cytokines such as IL10 and TGF-beta are also found in the tumor environment. Myeloid-derived suppressive cells (MDSCs) are recently found to have a significant role in immune suppression in ovarian cancer in murine studies. Furthermore, vascular endothelial growth factor (VEGF) is also known to have an immune-suppressing role besides its angiogenic role. All those concerted mechanisms result in the creation of an environment where the cancer is invincible and can grow unhampered.

CONCLUSION

Further knowledge of the mechanisms involved is needed to develop better strategies and improve the clinical applicability of immunotherapy. Effective immunotherapy must combine immune-activating strategies with elimination of immune-suppressing mechanisms. We believe that tilting the balance from an immune-suppressive to an immune-active environment may have an enormous impact on the disease.

Surgical debulking of ovarian cancer: what difference does it make?

Three-quarters of women who are newly diagnosed with invasive epithelial ovarian cancer present with stage III to IV disease. Recent data on the efficacy of neoadjuvant chemotherapy have served to challenge the conventional dogma that the preferred initial treatment is surgical debulking. Most of these patients will achieve remission regardless of initial treatment, but 80% to 90% of patients will ultimately relapse. The timing and clinical benefit of a second debulking operation is even more contentious. This article focuses on the recent debate of when or if patients with ovarian cancer should undergo aggressive surgical resection of bulky disease.