Cancer-induced immunosuppression is a major problem as it reduces the anti-tumor effects of immunotherapies. In cancer tissues, cancer cells, immune cells, and other stromal cells interact and create an immunosuppressive microenvironment through a variety of immunosuppressive factors. Some cancer subpopulations such as cancer cells undergoing epithelial-mesenchymal transition and cancer stem-like cells have immunosuppressive and immunoresistant properties. The production of immunosuppressive factors by cancer cells is mechanistically attributed to oncogenic signals frequently activated in cancer cells, including the STAT3, MAPK, NF-κB, and Wnt/β-catenin signals, which are upstream events leading to immunosuppressive cascades. Moreover, some of these signals are also activated in immunosuppressive immune cells stimulated by cancer-derived factors and contribute to their immunosuppressive activities. Therefore, targeting these signals both in cancer cells and immunosuppressive immune cells may result in the restoration of immunocompetence in cancer patients and improve current immunotherapy.

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Background:Although T-cell immunity is thought to be involved in the prognosis of epithelial ovarian cancer (EOC) patients, immunosuppressive conditions hamper antitumour immune responses. Thus, their mechanisms and overcoming strategies need to be investigated.Methods:The role of NF-κB in human EOC cells and macrophages was evaluated by in vitro production of immunosuppressive IL-6 and IL-8 by EOC cells and in vivo analysis of immune responses in nude mice implanted with human EOC cells using an NF-κB inhibitor DHMEQ.Results:In EOC patients, increased plasma IL-6, IL-8, and arginase were observed. The NF-κB inhibitor DHMEQ inhibited the production of IL-6 and IL-8 by EOC cell lines. Immunosuppression of human DCs and macrophages by culture supernatant of EOC cells was reversed with the pretreatment of DHMEQ. Administration of DHMEQ to nude mice implanted with human EOC resulted in the restoration of T-cell stimulatory activity of murine DCs along with the reduction of tumour accumulation and arginase expression of MDSCs. Nuclear factor-κB inhibition in tumour-bearing mice also enhanced antitumour effects of transferred murine naive T cells.Conclusions:NF-κB is involved in the immunosuppression induced by human EOC, and its inhibitor may restore antitumour immune responses, indicating that NF-κB is an attractive target for EOC treatment.

ObjectiveTo investigate pregnancy outcomes in women after abdominal radical trachelectomy (RT) for early-stage cervical cancer.MethodsThe patients’ background, fertility, and pregnancy outcomes were reviewed in a total of 61 pregnancies in 48 of 172 women who underwent abdominal RT at Keio University Hospital between September 2002 and December 2013.ResultsThere were 5 women with stage IA1, 2 with stage IA2, and 41 with stage IB1. Histological types were as follows: squamous cell carcinoma (n = 36), adenocarcinoma (n = 10), and adenosquamous cell carcinoma (n = 2). The pregnancy rate of women attempting to conceive after abdominal RT was 44% (48/109). The mean ± SD duration from abdominal RT to conception was 3.1 ± 1.9 years. Of 61 pregnancies, 42 pregnancies were achieved by fertility treatment (in vitro fertilization-embryo transfer, 39; intrauterine insemination, 3). After excluding one pregnancy without detailed clinical information, there were 42 live births (5 in 22–27 weeks, 11 in 28–33weeks, 20 in 34–36 weeks, and 6 in 37–38 weeks), 13 miscarriages, and 5 ongoing pregnancies. While there were 10 first trimester miscarriages, 3 pregnancies ended in the second trimester owing to chorioamnionitis. The mean gestational age at birth was 33 weeks of pregnancy. Thirty-seven neonates were appropriate-for-date, and one was small-for-date. Six pregnancies exhibited massive bleeding from the residual cervix in the late pregnancy. Preterm birth less than 34 weeks of pregnancy was related to premature rupture of the membrane (P < 0.05). Chorioamnionitis was evident in 9 of 11 pregnancies with preterm premature rupture of the membrane followed by birth at less than 34 weeks of pregnancy. No parturients exhibited lochiometra and endometritis postpartum.ConclusionsAbdominal RT provided favorable pregnancy outcomes, and fertility treatment could be advantageous to conception. Massive bleeding from the residual cervix as well as ascending infection might be characteristic features during pregnancy after abdominal RT.

Osteosarcoma is the most frequent, nonhematopoietic, primary malignant tumor of bone. Histopathologically, osteosarcoma is characterized by complex mixtures of different cell types with bone formation. The role of environmental factors in the formation of such a complicated tissue structure as osteosarcoma remains to be elucidated. Here, a newly established murine osteosarcoma model was used to clarify the roles of environmental factors such as fibroblast growth factor-2 (Fgf2) or leukemia-inhibitory factor (Lif) in the maintenance of osteosarcoma cells in an immature state. These factors were highly expressed in tumor environmental stromal cells, rather than in osteosarcoma cells, and they potently suppressed osteogenic differentiation of osteosarcoma cells in vitro and in vivo. Further investigation revealed that the hyperactivation of extracellular signal-regulated kinase (Erk)1/2 induced by these factors affected in the process of osteosarcoma differentiation. In addition, Fgf2 enhanced both proliferation and migratory activity of osteosarcoma cells and modulated the sensitivity of cells to an anticancer drug. The results of the present study suggest that the histology of osteosarcoma tumors which consist of immature tumor cells and pathologic bone formations could be generated dependent on the distribution of such environmental factors. The combined blockade of the signaling pathways of several growth factors, including Fgf2, might be useful in controlling the aggressiveness of osteosarcoma. Mol Cancer Res; 10(3); 454-68. Ó2012 AACR.