Harnessing the immune system for ovarian cancer therapy

The clinical course of ovarian cancer is often marked by periods of relapse and remission until chemo‐resistance develops. Patients in remission with minimal disease burdens are ideally suited for the evaluation of immune‐based strategies. Major obstacles to the development of successful immune strategies include the identification of tumor‐restricted immunogenic targets, generation of a sufficient immune response to cause tumor rejection, and approaches to overcome evasion of immune attack. Many questions remain as optimal strategies are developed, which include: (i) What is the best antigen form (e.g. peptides, proteins or tumor lysates)? (ii) What are the appropriate adjuvants? (iii) Are mono‐valent or multi‐valent vaccines likely to be more effective? (iv) What is the optimal frequency and duration of vaccination? (v) How should antigen‐specific responses be monitored? and (vi) How should the anti‐cancer response be maintained? In this review, we explore representative examples of immune strategies under investigation for patients with ovarian carcinoma which illustrate many of these issues. Basic principles generic to all these immunotherapeutic approaches will also be discussed.     

Dichotomy of Notch signalling in regulating tumour immune surveillance

Notch signalling is an evolutionarily conserved multifaceted pathway that controls diverse cellular processes. Its role in regulating development and tissue homeostasis is well established. Aberrant activation of the Notch pathway has been implicated in the initiation and progression of many types of cancers. However, although in some cancers Notch signalling acts as a tumour‐promoter, in others it is reported to suppress tumour growth and progression. Accumulating evidence suggests the involvement of both the innate and adaptive immune system in the development of various tumours. Currently, extensive studies on investigating the effects of Notch signalling in tumour immune surveillance are being carried out. Interestingly, recent literature shows how the changing expression of Notch genes in different T cell subsets like CD4 and CD8 helps in controlling anti‐tumour immune responses. In this review, we discuss in depth the roles of Notch signalling molecules and different immune cells in the context of the tumour microenvironment. We also outline how current knowledge can be exploited to develop novel therapies in order to control the propagation of cancer stem cells.     

卵巢癌的蛋白质组学研究进展

目前蛋白质组学已在卵巢癌的多方面研究中得到广泛的应用，如对卵巢癌发病机制的研究、卵巢癌生物标记物的筛选、卵巢癌信号转导通路的研究及协助诊断、协助卵巢癌分类、寻找治疗靶点等。随着人们对蛋白质组学认识的深入,卵巢癌发生发展的机制将会日渐明了。     

Hematopoietic cytokines as tumor markers in gynecological malignancies. A multivariate analysis in epithelial ovarian cancer patients

We investigated plasma levels of selected hematopoietic cytokines: stem cell factor (SCF), granulocyte-macrophage colony-stimulating factor (GM-CSF), granulocyte colony-stimulating factor (G-CSF), and macrophage colony-stimulating factor (M-CSF) and the tumor marker cancer antigen (CA 125) in epithelial ovarian cancer patients as compared with control groups: benign ovarian tumor patients (cysts) and healthy subjects. Cytokine levels were determined by enzyme-linked immunosorbent assay, CA 125 – using the chemiluminescent microparticle immunoassay method. Our results have demonstrated significant differences in the concentrations of M-CSF, G-CSF, SCF (with the exception of GM-CSF), and CA 125 between the groups of ovarian cancer patients, cysts patients, and the healthy controls. When compared with CA 125, M-CSF has equal or higher values of diagnostic sensitivity and specificity. The M-CSF area under the receiver-operating characteristic curve (AUC) was the largest from all the cytokines tested and slightly lower than the AUC of CA 125. These findings suggest the usefulness of M-CSF in diagnosing ovarian cancer, especially when discriminating between cancer and non-carcinoma lesions.     

Somatic mutational profiles of stage II and III gastric cancer according to tumor microenvironment immune type

We aimed to determine somatic mutational profiles of stage II/III gastric cancers (GCs) according to their tumor microenvironment immune types (TMITs), which classify cancer based on co‐assessment of PD‐L1 expression and CD8⁺ tumor infiltrating lymphocytes. Eighty patients with stage II/III GC were classified as follows: TMIT I (PD‐L1⁺/CD8^High), TMIT II (PD‐L1^?/CD8^Low), TMIT III (PD‐L1⁺/CD8^Low), and TMIT IV (PD‐L1^?/CD8^High). Deep targeted sequencing using a panel of 170 cancer‐related genes was performed on an Illumina HiSeq‐2500 system. Most frequently mutated genes included GNAQ (41.3%), TP53 (38.8%), CREBBP (35.0%), and MAP3K1 (35.0%). PIK3CA mutations were observed more frequently in TMIT I (45.8%) and III (66.7%), than in II (12.0%) and IV (8.0%). Other genes with enriched mutations within TMIT I included ATM (33.3%), BRCA2 (33.3%), MAP3K4 (29.2%), and FLT4 (25.0%). FGFR3, MAP3K1, and RUNX1 mutations were more frequently found in TMIT II. TMIT III had a unique somatic mutation profile harboring enriched mutations of histone modifiers including CREBBP and KMT2A, and we found FGFR2 amplification exclusively within TMIT IV. Fuzzy clustering analysis based on somatic mutation frequencies identified a hypermutated group (cluster 1) and a hypomutated group (cluster 2). Cluster 1 had significant associations with TMIT I, EBV⁺ GCs, and MSI‐H GCs (P = .023, .014, and .004), and had better overall survival (P = .057) than Cluster 2. TMIT I, EBV⁺, and MSI‐H GCs were estimated to have greater tumor mutational burden (P = .023, .003, and .015). By analyzing somatic mutation profiles according to TMIT classification, we identified TMIT‐specific genetic alterations that provide clues for biological linkage between GC genetics and microenvironment.     

Defining lymphocyte‐predominant breast cancer by the proportion of lymphocyte‐rich stroma and its significance in routine histopathological diagnosis

Lymphocyte‐predominant breast cancer (LPBC) defined by the density of stromal lymphocytes shows favorable behavior. However, considerable distribution heterogeneity of lymphocytes is a major problem. The present study defined LPBC by the proportion of lymphocyte‐rich stroma with the cut‐off values of 30, 50, and 75%, and clinicopathologically analyzed mainly LPBC (area > 30%) defined by the cut‐off value of 30%. LPBCs (area > 30%), 39 cases in total, were composed mainly of triple‐negative and HER2⁺/ER^‐ subtypes, without any luminal A‐like subtype. LPBCs were composed predominantly of histological grade 3 tumors, without any grade 1 lesions. Multivariate analyses on 477 consecutive tumors revealed that ER‐negativity and grade 3 status associated significantly with LPBC. LPBC (area > 30%) showed better disease‐free survival than grade‐matched controls, and it was a good indicator of complete pathological remission after pre‐operative chemotherapy. Patients with LPBC with the cut‐off value of 50% and that of 75% showed 100% disease‐free survival. These results demonstrated the validity of our definition of LPBC. Our data also suggest that de‐differentiated cancers without TILs could be regarded as high‐grade cancer without lymphocyte‐mediated responses. In conclusion, the definition of LPBC by the proportion of lymphoid stroma is useful for prognostication of high grade breast cancer in routine diagnosis.     

Construction of integrated microRNA and mRNA immune cell signatures to predict survival of patients with breast and ovarian cancer

In the tumor microenvironment, immune cells have emerged as key regulators of cancer progression. While much work has focused on characterizing tumor‐related immune cells through gene expression profiling, microRNAs (miRNAs) have also been reported to regulate immune cells in the tumor microenvironment. Using regression‐based computational methods, we have constructed for the first time, immune cell signatures based on miRNA expression from The Cancer Genome Atlas breast and ovarian cancer datasets. Combined with existing mRNA immune cell signatures, the integrated mRNA‐miRNA leukocyte signatures are better able to delineate prognostic immune cell subsets within both cancers compared to the mRNA or miRNA signatures alone. Moreover, using the miRNA signatures, the anti‐inflammatory M2 macrophages emerged as the most significantly prognostic cell type in the breast cancer data (HR [hazard ratio]: 12.9; CI [confidence interval]: 3.09‐52.9; P = 4.22E?4), whereas the pro‐inflammatory M1 macrophages emerged as the most prognostic immune cell type in the ovarian cancer data (HR: 0.2; CI: 0.04‐0.56, P = 5.02E?3). These results suggest that our integrated miRNA and mRNA leukocyte signatures could be used to better delineate prognostic leukocyte subsets within cancers, whereas continued investigation may further support the regulatory relationships predicted between the miRNAs and immune cells found within our signature matrices.     

A histogenetic consideration of ovarian mucinous tumors based on an analysis of lesions associated with teratomas or Brenner tumors

To Investigate the histogenesis of ovarian mucinous tumors, clinicopathologic and histologic studies of mucinous tumors associated with teratomas or Brenner tumors were performed. Of 458 ovarian mucinous tumors, 13 (2.8%) and 8 (1.7%) were associated wlth teratomas or Brenner tumors, respectively. Of patients younger than 40 years, 5.1% had teratomas. Of patients 50 years or older, 3.5% had Brenner tumors. Histologically, nine lesions with teratomas and six lesions with Brenner tumors showed transitions or intimate admixtures of both eiements. The findings of the present study suggest that teratomas and Brenner tumors make small contributions to the histogenesis of ovarian mucinous tumors but may give rise to some mucinous tumors, especially in younger patients and older patients, respectively.     

High‐throughput sequencing of T‐cell receptors reveals a homogeneous repertoire of tumour‐infiltrating lymphocytes in ovarian cancer

The cellular adaptive immune system mounts a response to many solid tumours mediated by tumour‐infiltrating T lymphocytes (TILs). Basic measurements of these TILs, including total count, show promise as prognostic markers for a variety of cancers, including ovarian and colorectal. In addition, recent therapeutic advances are thought to exploit this immune response to effectively fight melanoma, with promising studies showing efficacy in additional cancers. However, many of the basic properties of TILs are poorly understood, including specificity, clonality, and spatial heterogeneity of the T‐cell response. We utilize deep sequencing of rearranged T‐cell receptor beta (TCRB) genes to characterize the basic properties of TILs in ovarian carcinoma. Due to somatic rearrangement during T‐cell development, the TCR beta chain sequence serves as a molecular tag for each T‐cell clone. Using these sequence tags, we assess similarities and differences between infiltrating T cells in discretely sampled sections of large tumours and compare to T cells from peripheral blood. Within the limits of sensitivity of our assay, the TIL repertoires show strong similarity throughout each tumour and are distinct from the circulating T‐cell repertoire. We conclude that the cellular adaptive immune response within ovarian carcinomas is spatially homogeneous and distinct from the T‐cell compartment of peripheral blood. Copyright © 2013 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.     

Differential display identifies overexpression of the USP36 gene, encoding a deubiquitinating enzyme, in ovarian cancer

Objectives. To find potential diagnostic markers or therapeutic targets, we used differential display technique to identify genes that are over or under expressed in human ovarian cancer.     

Spatial maps of T cell receptors and transcriptomes reveal distinct immune niches and interactions in the adaptive immune response

1. Download : Download high-res image (188KB)
2. Download : Download full-size image

     

Mucinous borderline ovarian tumors: points of general agreement and persistent controversies regarding nomenclature, diagnostic criteria, and behavior

This report focuses on the borderline category of ovarian mucinous tumors and summarizes the points of general agreement and persistent controversies identified by experts in the field who participated in the Borderline Ovarian Tumor Workshop held in Bethesda, MD, in August 2003. Points of agreement and persistent controversies regarding nomenclature, diagnostic criteria, and behavior are addressed for the following ovarian mucinous tumor categories: mucinous borderline ovarian tumor (M-BOT; synonymously referred to as atypical proliferative mucinous tumor of ovary or mucinous ovarian tumor of low malignant potential), M-BOT with intraepithelial carcinoma, and M-BOT with microinvasion. The morphologic spectrum of M-BOTs with regard to distinction from mucinous cystadenoma and the confluent glandular/expansile type of invasive mucinous carcinoma is also addressed. Non-ovarian mucinous tumors, including the secondary ovarian mucinous tumors associated with pseudomyxoma peritonei and metastatic mucinous carcinomas with a deceptive pattern of invasion, are recognized as tumors that can simulate primary M-BOTs. Improved classification of these mucinous tumors has clarifed the behavior of true M-BOTs by excluding these simulators from the M-BOT category.     

Control of ovarian function by the immune system: Is this a plausible and necessary hypothesis?

A recently presented hypothesis, according to which cyclic selection of a specific number of follicles for ovulation is brought about by immune mechanisms, will be discussed critically. The arguments and conclusions within the framework of this hypothesis are either not convincing or even at variance with well established facts. It is questioned whether there is any need for such a dramatic extension of the commonly accepted concept for neuroendocrine control of ovarian function.     

Cytologic features of ovarian granulosa cell tumors in pleural and ascitic fluids

Adult granulosa cell tumor (AGCT) is an uncommon neoplasm of the ovary with potential for aggressive behavior and late recurrence. The most important prognostic factor for AGCT is tumor stage. Thus, cytological assessment of pleural or ascitic fluids is crucial for initial staging and subsequent patient management. We report herein two cases of ovarian AGCT presenting with exfoliated tumor cells in pleural and ascitic fluid. The first case involved a 61‐year‐old woman who presented with stage Ic (a) AGCT. Seven years after initial diagnosis, pleural effusion and pleural dissemination were identified. The second case involved a 50‐year‐old woman who presented with stage IV AGCT with massive ascites and right pleural effusion. Fluid cytology from both cases showed cohesive or loose clusters of small uniform neoplastic cells with round‐to‐oval nuclei, coffee‐bean‐shaped nuclear grooves, small nucleoli, and scant cytoplasm. Call‐Exner bodies were also observed in these cytologic specimens. In the differential diagnosis of small monomorphic tumor cells in pleural effusion or ascites, coffee‐bean‐shaped nuclear grooves and cell clusters forming Call‐Exner bodies are diagnostic clues of AGCT. Diagn. Cytopathol. 2015;43:581–584. © 2015 Wiley Periodicals, Inc.     

Ovarian cancer stem cells promote tumour immune privilege and invasion via CCL5 and regulatory T cells

Emerging evidence indicates a link between the increased proportion of regulatory T cells (T_regs) and reduced survival in patients who have been diagnosed with cancer. Cancer stem cells (CSCs) have been indicated to play a vital role in tumour initiation, drug resistance and recurrence. However, the relationship between T_regs and CSCs remains largely unknown. Here, we sorted out ovarian cancer stem‐like side population (SP) cells and CD133⁺ cells to investigate the influence of ovarian CSCs on T_regs. Among the various immune‐related molecules that we assessed, C‐C motif chemokine ligand 5 (CCL5) was the most elevated in ovarian CSCs relative to that in the non‐CSCs. The expression of its receptor, C‐C motif chemokine receptor 5 (CCR5), was also increased on the surface of T_regs in ovarian cancer patients. This receptor‐ligand expression profile indicated that ovarian CSCs recruit T_regs via CCL5–CCR5 interactions. We further assessed the expression of interleukin (IL)‐10 in T_regs cultured with different cancer cells. T_regs cultured in conditioned medium (CM) from ovarian CD133⁺ cells expressed a higher level of IL‐10 than T_regs cultured in CM from CD133^– cells, indicating that T_regs exert pronounced immune‐inhibitory functions in CSC‐rich environments. Furthermore, co‐culture with ovarian cancer cell lines induced the expression of matrix metalloproteinase‐9 (MMP9) in T_regs which, in turn, enhanced the degradation of the extracellular matrix and enabled the invasion of tumour cells, thereby facilitating tumour metastasis. For the first time, to our knowledge, our findings describe the relationship between ovarian CSCs and T_regs, and demonstrated that these two cell populations co‐operate to promote tumour immune tolerance and enhance tumour progression.     

PI3K/AKT信号通路与Survivin在上皮性卵巢肿瘤中的表达及相关性

目的：探讨PI3K/AKT信号通路中PI3K、AKT及Survivin在上皮性卵巢肿瘤中的表达及其相关性。方法：应用免疫组织化学SP法及Image-ProPlus图像分析软件检测PI3K、AKT、Survivin蛋白分别在30例正常卵巢组织、30例上皮性卵巢良性肿瘤、30例上皮性卵巢交界性肿瘤及30例上皮性卵巢癌中的表达情况。结果：PI3K、AKT、Survivin在恶性组中的阳性表达率显著高于其它三组,其表达与患者临床病理特征无关,PI3K与Survivin、PI3K与AKT及AKT与Survivin之间的表达呈正相关。结论：PI3K/AKT信号通路中PI3K、AKT及凋亡抑制蛋白Survivin与上皮性卵巢癌的发生、发展有关;联合检测PI3K、AKT、Survivin有望成为上皮性卵巢癌临床诊断与鉴别诊断的参考指标。     

PD‐L1 expression and deficient mismatch repair in ductal adenocarcinoma of the prostate

This study aimed to investigate the expression of programmed death receptor ligand 1 (PD‐L1) and deficient mismatch repair (dMMR) in ductal adenocarcinoma of the prostate. A tissue microarray of 32 ductal and 42 grade‐matched acinar adenocarcinomas was used. Slides were stained for PD‐L1, PD‐L2, MMR proteins, CD4 and CD8. PD‐L1 expression in tumor cells was only seen in 3% (1/34) of ductal and 5% (2/42) of acinar adenocarcinomas (p = 1.0), while PD‐L1 expression in tumor‐infiltrating immune cells was seen in 29% (10/34) of ductal and 14% (6/42) of acinar adenocarcinomas (p = 0.16). dMMR, as defined by loss of one or more of the MMR proteins, was identified in 5% (4/73) of cases, including 1 ductal and 3 acinar adenocarcinomas. There was a suggested association between infiltration of CD8+ lymphocytes and ductal subtype (p = 0.04) but not between CD4+ lymphocytes and tumor type (p = 0.28). The study shows that both dMMR and PD‐L1 expression is uncommon in tumor cells of both ductal and acinar adenocarcinoma of the prostate, while PD‐L1 expression in tumor‐infiltrating immune cells is a more common finding.