HLA class I antigen processing machinery component expression and intratumoral T-Cell infiltrate as independent prognostic markers in ovarian carcinoma

Spatial Profiling of Ovarian Carcinoma and Tumor Microenvironment Evolution under Neoadjuvant Chemotherapy

PURPOSE

This study investigates changes in CD8+ cells, CD8+/Foxp3 ratio, HLA I expression, and immune coregulator density at diagnosis and upon neoadjuvant chemotherapy (NACT), correlating changes with clinical outcomes.

EXPERIMENTAL DESIGN

Multiplexed immune profiling and cell clustering analysis were performed on paired matched ovarian cancer samples to characterize the immune tumor microenvironment (iTME) at diagnosis and under NACT in patients enrolled in the CHIVA trial (NCT01583322).

RESULTS

Several immune cell (IC) subsets and immune coregulators were quantified pre/post-NACT. At diagnosis, patients with higher CD8+ T cells and HLA I+-enriched tumors were associated with a better outcome. The CD8+/Foxp3+ ratio increased significantly post-NACT in favor of increased immune surveillance, and the influx of CD8+ T cells predicted better outcomes. Clustering analysis stratified pre-NACT tumors into four subsets: high Binf, enriched in B clusters; high Tinf and low Tinf, according to their CD8+ density; and desert clusters. At baseline, these clusters were not correlated with patient outcomes. Under NACT, tumors were segregated into three clusters: high BinfTinf, low Tinf, and desert. The high BinfTinf, more diverse in IC composition encompassing T, B, and NK cells, correlated with improved survival. PDL1 was rarely expressed, whereas TIM3, LAG3, and IDO1 were more prevalent.

CONCLUSIONS

Several iTMEs exist during tumor evolution, and the NACT impact on iTME is heterogeneous. Clustering analysis of patients unravels several IC subsets within ovarian cancer and can guide future personalized approaches. Targeting different checkpoints such as TIM3, LAG3, and IDO1, more prevalent than PDL1, could more effectively harness antitumor immunity in this anti-PDL1-resistant malignancy.

Assessment of cancer cell-expressed HLA class I molecules and their immunopathological implications

Immunotherapy using immune checkpoint inhibitors (ICIs) has shown superior efficacy compared with conventional chemotherapy in certain cancer types, establishing immunotherapy as the fourth standard treatment alongside surgical intervention, chemotherapy, and radiotherapy. In cancer immunotherapy employing ICIs, CD8-positive cytotoxic T lymphocytes are recognized as the primary effector cells. For effective clinical outcomes, it is essential that the targeted cancer cells express HLA class I molecules to present antigenic peptides derived from the tumor. However, cancer cells utilize various mechanisms to downregulate or lose HLA class I molecules from their surface, resulting in evasion from immune surveillance. Correlations between prognosis and the integrity of HLA class I molecules expressed by cancer cells have been consistently found across different types of cancer. This paper provides an overview of the regulatory mechanisms of HLA class I molecules and their role in cancer immunotherapy, with a particular emphasis on the significance of utilizing pathological tissues to evaluate HLA class I molecules expressed in cancer cells.

Proteogenomic analysis of enriched HGSOC tumor epithelium identifies prognostic signatures and therapeutic vulnerabilities

We performed a deep proteogenomic analysis of bulk tumor and laser microdissection enriched tumor cell populations from high-grade serous ovarian cancer (HGSOC) tissue specimens spanning a broad spectrum of purity. We identified patients with longer progression-free survival had increased immune-related signatures and validated proteins correlating with tumor-infiltrating lymphocytes in 65 tumors from an independent cohort of HGSOC patients, as well as with overall survival in an additional 126 HGSOC patient cohort. We identified that homologous recombination deficient (HRD) tumors are enriched in pathways associated with metabolism and oxidative phosphorylation that we validated in independent patient cohorts. We further identified that polycomb complex protein BMI-1 is elevated in HR proficient (HRP) tumors, that elevated BMI-1 correlates with poor overall survival in HRP but not HRD HGSOC patients, and that HRP HGSOC cells are uniquely sensitive to BMI-1 inhibition.

Research progress of extracellular vesicles in the treatment of ovarian diseases (Review)

The ovary is an essential reproductive organ in the female organism and its development seriously affects the physical and mental health of female patients. Ovarian diseases include ovarian cancer, premature ovarian insufficiency (POI) and polycystic ovary syndrome (PCOS). Women should pay attention to the most effective treatments for this condition because it is one of the most prevalent gynecological illnesses at present. Extracellular vesicles (EVs), which are smaller vesicles that mediate the exchange of cellular information, include the three categories of exosomes, microvesicles and apoptotic bodies. They are able to transport proteins, RNA and other substances to adjacent or distal cells, thus allowing cellular and tissue homeostasis to be maintained. Numerous previous studies have revealed that EVs are crucial for the treatment of ovarian diseases. They are known to transport its contents to ovarian cancer cells as well as other ovarian cells such as granulosa cells, affecting the development of ovarian disease processes. Therefore, this extracellular vesicle may be involved as a target in the therapeutic process of ovarian disease and may have great potential in the treatment of ovarian disease. In the present review, the role of EVs in the development of three ovarian diseases, including ovarian cancer, POI and PCOS, was mainly summarizes. It is expected that this will provide some theoretical support for the treatment of ovarian disease.

Harnessing tumor immunogenomics: Tumor neoantigens in ovarian cancer and beyond

Ovarian cancer is a major cause of death among gynecological cancers due to its highly aggressive nature. Immunotherapy has emerged as a promising avenue for ovarian cancer treatment, offering targeted approaches with reduced off-target effects. With the advent of next-generation sequencing, it has become possible to identify genomic alterations that can serve as potential targets for immunotherapy. Furthermore, immunogenomics research has revealed the importance of genetic alterations in shaping the cancer immune responses. However, the heterogeneity of immunogenicity and the low tumor mutation burden pose challenges for neoantigen-based immunotherapies. Further research is needed to identify neoantigen-specific tumor-infiltrating lymphocytes (TIL) and establish guidelines for patient inclusion criteria in TIL-based therapy. The study of neoantigens and their implications in ovarian cancer immunotherapy holds great promise, and efforts focused on personalized treatment strategies, refined neoantigen selection, and optimized therapeutic combinations will contribute to improving patient outcomes in the future.

A novel defined risk signature of endoplasmic reticulum stress-related genes for predicting the prognosis and immune infiltration status of ovarian cancer

Endoplasmic reticulum (ER) stress, as an emerging hallmark feature of cancer, has a considerable impact on cell proliferation, metastasis, invasion, and chemotherapy resistance. Ovarian cancer (OvCa) is one of the leading causes of cancer-related mortality across the world due to the late stage of disease at diagnosis. Studies have explored the influence of ER stress on OvCa in recent years, while the predictive role of ER stress-related genes in OvCa prognosis remains unexplored. Here, we enrolled 552 cases of ER stress-related genes involved in OvCa from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) cohorts for the screening of prognosis-related genes. The least absolute shrinkage and selection operator (LASSO) regression was applied to establish an ER stress-related risk signature based on the TCGA cohort. A seven-gene signature revealed a favorable predictive efficacy for the TCGA, International Cancer Genome Consortium (ICGC), and another GEO cohort (P<0.001, P<0.001, and P=0.04, respectively). Moreover, functional annotation indicated that this signature was enriched in cellular response and senescence, cytokines interaction, as well as multiple immune-associated terms. The immune infiltration profiles further delineated an immunologic unresponsive status in the high-risk group. In conclusion, ER stress-related genes are vital factors predicting the prognosis of OvCa, and possess great application potential in the clinic.

Loss of Major Histocompatibility Complex Class I, CD8 + Tumor-infiltrating Lymphocytes, and PD-L1 Expression in Ovarian Clear Cell Carcinoma

Ovarian clear cell carcinoma (OCCC), a chemoresistant ovarian cancer, shows a modest response to anti-programmed death-1/programmed death ligand-1 (PD-1/PD-L1) therapies. The effects of anti-PD-1/PD-L1 therapies rely on cytotoxic T-cell response, which is triggered by antigen presentation mediated by major histocompatibility complex (MHC) class I. The loss of MHC class I with simultaneous PD-L1 expression has been noted in several cancer types; however, these findings and their prognostic value have rarely been evaluated in OCCC. We collected data from 76 patients with OCCC for clinicopathologic analysis. Loss of MHC class I expression was seen in 44.7% of the cases including 39.3% to 47.4% of the PD-L1 + cases and was associated with fewer CD8 + tumor-infiltrating lymphocytes (TILs). PD-L1 positivity was associated with a higher number of CD8 + TILs. Cox proportional hazard models showed that high (≥50/mm 2 ) CD8 + TILs was associated with shorter disease-specific survival (hazard ratio [HR]=3.447, 95% confidence interval [CI]: 1.222-9.720, P =0.019) and overall survival (HR=3.053, 95% CI: 1.105-8.43, P =0.031). PD-L1 positivity using Combined Positive Score was associated with shorter progression-free survival (HR=3.246, 95% CI: 1.435-7.339, P =0.005), disease-specific survival (HR=4.124, 95% CI: 1.403-12.116, P =0.010), and overall survival (HR=4.489, 95% CI: 1.553-12.972, P =0.006). Loss of MHC class I may contribute to immune evasion and resistance to anti-PD-1/PD-L1 therapies in OCCC, and CD8 + TILs and PD-L1 positivity using Combined Positive Score may have a negative prognostic value.

Dynamic Changes in the Extracellular Matrix in Primary, Metastatic, and Recurrent Ovarian Cancers

Cancer-associated fibroblasts (CAFs) and their extracellular matrix are active participants in cancer progression. While it is known that functionally different subpopulations of CAFs co-exist in ovarian cancer, it is unclear whether certain CAF subsets are enriched during metastatic progression and/or chemotherapy. Using computational image analyses of patient-matched primary high-grade serous ovarian carcinomas, synchronous pre-chemotherapy metastases, and metachronous post-chemotherapy metastases from 42 patients, we documented the dynamic spatiotemporal changes in the extracellular matrix, fibroblasts, epithelial cells, immune cells, and CAF subsets expressing different extracellular matrix components. Among the different CAF subsets, COL11A1+ CAFs were associated with linearized collagen fibers and exhibited the greatest enrichment in pre- and post-chemotherapy metastases compared to matched primary tumors. Although pre- and post-chemotherapy metastases were associated with increased CD8+ T cell infiltration, the infiltrate was not always evenly distributed between the stroma and cancer cells, leading to an increased frequency of the immune-excluded phenotype where the majority of CD8+ T cells are present in the tumor stroma but absent from the tumor parenchyma. Overall, most of the differences in the tumor microenvironment were observed between primary tumors and metastases, while fewer differences were observed between pre- and post-treatment metastases. These data suggest that the tumor microenvironment is largely determined by the primary vs. metastatic location of the tumor while chemotherapy does not have a significant impact on the host microenvironment.

Integration of local and systemic immunity in ovarian cancer: Implications for immunotherapy

Cancer is a disease that induces many local and systemic changes in immunity. The difficult nature of ovarian cancer stems from the lack of characteristic symptoms that contributes to a delayed diagnosis and treatment. Despite the enormous progress in immunotherapy, its efficacy remains limited. The heterogeneity of tumors, lack of diagnostic biomarkers, and complex immune landscape are the main challenges in the treatment of ovarian cancer. Integrative approaches that combine the tumor microenvironment - local immunity - together with periphery - systemic immunity - are urgently needed to improve the understanding of the disease and the efficacy of treatment. In fact, multiparametric analyses are poised to improve our understanding of ovarian tumor immunology. We outline an integrative approach including local and systemic immunity in ovarian cancer. Understanding the nature of both localized and systemic immune responses will be crucial to boosting the efficacy of immunotherapies in ovarian cancer patients.

Immunobiology of high-grade serous ovarian cancer: lessons for clinical translation

Treatment of high-grade serous ovarian cancer (HGSOC) remains challenging. Although HGSOC can potentially be responsive to immunotherapy owing to endogenous immunity at the molecular or T cell level, immunotherapy for this disease has fallen short of expectations to date. This Review proposes a working classification for HGSOC based on the presence or absence of intraepithelial T cells, and elaborates the putative mechanisms that give rise to such immunophenotypes. These differences might explain the failures of existing immunotherapies, and suggest that rational therapeutic approaches tailored to each immunophenotype might meet with improved success. In T cell-inflamed tumours, treatment could focus on mobilizing pre-existing immunity and strengthening the activation of T cells embedded in intraepithelial tumour myeloid niches. Conversely, in immune-excluded and immune-desert tumours, treatment could focus on restoring inflammation by reprogramming myeloid cells, stromal cells and vascular epithelial cells. Poly(ADP-ribose) polymerase (PARP) inhibitors, low-dose radiotherapy, epigenetic drugs and anti-angiogenesis therapy are among the tools available to restore T cell infiltration in HGSOC tumours and could be implemented in combination with vaccines and redirected T cells.

Immune Tumor Microenvironment in Ovarian Cancer Ascites

Ovarian cancer (OC) has a specific type of metastasis, via transcoelomic, and most of the patients are diagnosed at advanced stages with multiple tumors spread within the peritoneal cavity. The role of Malignant Ascites (MA) is to serve as a transporter of tumor cells from the primary location to the peritoneal wall or to the surface of the peritoneal organs. MA comprise cellular components with tumor and non-tumor cells and acellular components, creating a unique microenvironment capable of modifying the tumor behavior. These microenvironment factors influence tumor cell proliferation, progression, chemoresistance, and immune evasion, suggesting that MA play an active role in OC progression. Tumor cells induce a complex immune suppression that neutralizes antitumor immunity, leading to disease progression and treatment failure, provoking a tumor-promoting environment. In this review, we will focus on the High-Grade Serous Carcinoma (HGSC) microenvironment with special attention to the tumor microenvironment immunology.

Dendritic Cell Vaccines: A Promising Approach in the Fight against Ovarian Cancer

Simple Summary

With an overall 5-year survival of only 20% for advanced-stage ovarian cancer patients, enduring and effective therapies are a highly unmet clinical need. Current standard-of-care therapies are able to improve progression-free survival; however, patients still relapse. Moreover, immunotherapy has not resulted in clear patient benefits so far. In this situation, dendritic cell vaccines can serve as a potential therapeutic addition against ovarian cancer. In the current review, we provide an overview of the different dendritic cell subsets and the roles they play in ovarian cancer. We focus on the advancements in dendritic cell vaccination against ovarian cancer and highlight the key outcomes and pitfalls associated with currently used strategies. Finally, we address future directions that could be taken to improve the dendritic cell vaccination outcomes in ovarian cancer.

Abstract

Ovarian cancer (OC) is the deadliest gynecological malignancy in developed countries and is the seventh-highest cause of death in women diagnosed with cancer worldwide. Currently, several therapies are in use against OC, including debulking surgery, chemotherapy, as well as targeted therapies. Even though the current standard-of-care therapies improve survival, a vast majority of OC patients relapse. Additionally, immunotherapies have only resulted in meager patient outcomes, potentially owing to the intricate immunosuppressive nexus within the tumor microenvironment. In this scenario, dendritic cell (DC) vaccination could serve as a potential addition to the therapeutic options available against OC. In this review, we provide an overview of current therapies in OC, focusing on immunotherapies. Next, we highlight the potential of using DC vaccines in OC by underscoring the different DC subsets and their functions in OC. Finally, we provide an overview of the advances and pitfalls of current DC vaccine strategies in OC while providing future perspectives that could improve patient outcomes.

Systemic Immune-Inflammation Index Predicts Outcomes in Platinum-Resistant Relapsed Ovarian Cancer

We explored the prognostic impact of simple indices that reflect the immunological milieu (neutrophils to lymphocyte ratio [NLR] and systemic immune-inflammation [SII]) in 49 platinum-resistant relapsed ovarian cancer patients. The median progression-free survival (PFS) and overall survival (OS) were 4 and 8 months, respectively. Patients with a lower NLR (≤2.89) had a better PFS (5 vs. 2 months [p = 0.02]) and OS (9 vs. 5 months [p = 0.20]). Factors associated with a worse PFS were NLR > 2.8 (hazard ratio [HR] =2.32, p = 0.02) and SII > 639 (HR =3.70, p = 0.002). SII > 639 independently predicted PFS (HR =4.13, p = 0.03). Future studies should study the validity of inflammatory markers and could consider incorporating it as a biomarker in clinical trials.

ABCA1 is associated with the development of acquired chemotherapy resistance and predicts poor ovarian cancer outcome

Aim: This study investigated the ATP binding cassette (ABC) transporter (ABCA1, ABCB1, ABCB3, ABCC2 and ABCG2) expression in high grade serous ovarian cancer (HGSOC) tissues, cell lines and primary cells to determine their potential relationship with acquired chemotherapy resistance and patient outcome. Methods: ABC transporter mRNA and protein expression (ABCA1, ABCB1, ABCB3, ABCC2 and ABCG2) was assessed in publicly available datasets and in a tissue microarray (TMA) cohort of HGSOC at diagnosis, respectively. ABC transporter mRNA expression was also assessed in chemosensitive ovarian cancer cell lines (OVCAR-5 and CaOV3) versus matching cell lines with acquired carboplatin resistance and in primary HGSOC cells from patients with chemosensitive disease at diagnosis (n = 10) as well as patients with acquired chemotherapy resistance at relapse (n = 6). The effects of the ABCA1 inhibitor apabetalone in carboplatin-sensitive and -resistant cell lines were also investigated. Results: High ABCA1 mRNA and protein expression was found to be significantly associated with poor patient outcome. ABCA1 mRNA and protein levels were significantly increased in ovarian cancer cell lines (OVCAR-5 CBPR and CaOV3 CBPR) with acquired carboplatin resistance. ABCA1 mRNA was significantly increased in primary HGSOC cells obtained from patients with acquired chemotherapy resistance. Apabetalone treatment reduced ABCA1 protein expression and increased the sensitivity of both parental and carboplatin-resistant ovarian cancer cells to carboplatin. Conclusion: These results suggest that inhibiting ABCA1 transporter may be useful in overcoming acquired chemotherapy resistance and improving outcome for patients with HGSOC.

Racial Differences in the Tumor Immune Landscape and Survival of Women with High-Grade Serous Ovarian Carcinoma

BACKGROUND

Tumor-infiltrating lymphocytes (TIL) confer a survival benefit among patients with ovarian cancer; however, little work has been conducted in racially diverse cohorts.

METHODS

The current study investigated racial differences in the tumor immune landscape and survival of age- and stage-matched non-Hispanic Black and non-Hispanic White women with high-grade serous ovarian carcinoma (HGSOC) enrolled in two population-based studies (n = 121 in each racial group). We measured TILs (CD3+), cytotoxic T cells (CD3+CD8+), regulatory T cells (CD3+FoxP3+), myeloid cells (CD11b+), and neutrophils (CD11b+CD15+) via multiplex immunofluorescence. Multivariable Cox proportional hazard regression was used to estimate the association between immune cell abundance and survival overall and by race.

RESULTS

Overall, higher levels of TILs, cytotoxic T cells, myeloid cells, and neutrophils were associated with better survival in the intratumoral and peritumoral region, irrespective of tissue compartment (tumor, stroma). Improved survival was noted for T-regulatory cells in the peritumoral region and in the stroma of the intratumoral region, but no association for intratumoral T-regulatory cells. Despite similar abundance of immune cells across racial groups, associations with survival among non-Hispanic White women were consistent with the overall findings, but among non-Hispanic Black women, most associations were attenuated and not statistically significant.

CONCLUSIONS

Our results add to the existing evidence that a robust immune infiltrate confers a survival advantage among women with HGSOC; however, non-Hispanic Black women may not experience the same survival benefit as non-Hispanic White women with HGSOC.

IMPACT

This study contributes to our understanding of the immunoepidemiology of HGSOC in diverse populations.

Splenic and PB immune recovery in neoadjuvant treated gastrointestinal cancer patients

In recent years, immune therapy, notably immune checkpoint inhibitors (ICI), in conjunction with chemotherapy and surgery has demonstrated therapeutic activity for some tumor types. However, little is known about the optimal combination of immune therapy with standard of care therapies and approaches. In patients with gastrointestinal (GI) cancers, especially pancreatic ductal adenocarcinoma (PDAC), preoperative (neoadjuvant) chemotherapy has increased the number of patients who can undergo surgery and improved their responses. However, most chemotherapy is immunosuppressive, and few studies have examined the impact of neoadjuvant chemotherapy (NCT) on patient immunity and/or the optimal combination of chemotherapy with immune therapy. Furthermore, the majority of chemo/immunotherapy studies focused on immune regulation in cancer patients have focused on postoperative (adjuvant) chemotherapy and are limited to peripheral blood (PB) and occasionally tumor infiltrating lymphocytes (TILs); representing a minority of immune cells in the host. Our previous studies examined the phenotype and frequencies of myeloid and lymphoid cells in the PB and spleens of GI cancer patients, independent of chemotherapy regimen. These results led us to question the impact of NCT on host immunity. We report herein, unique studies examining the splenic and PB phenotypes, frequencies, and numbers of myeloid and lymphoid cell populations in NCT treated GI cancer patients, as compared to treatment naïve cancer patients and patients with benign GI tumors at surgery. Overall, we noted limited immunological differences in patients 6 weeks following NCT (at surgery), as compared to treatment naive patients, supporting rapid immune normalization. We observed that NCT patients had a lower myeloid derived suppressor cells (MDSCs) frequency in the spleen, but not the PB, as compared to treatment naive cancer patients and patients with benign GI tumors. Further, NCT patients had a higher splenic and PB frequency of CD4+ T-cells, and checkpoint protein expression, as compared to untreated, cancer patients and patients with benign GI tumors. Interestingly, in NCT treated cancer patients the frequency of mature (CD45RO+) CD4+ and CD8+ T-cells in the PB and spleens was higher than in treatment naive patients. These differences may also be associated, in part with patient stage, tumor grade, and/or NCT treatment regimen. In summary, the phenotypic profile of leukocytes at the time of surgery, approximately 6 weeks following NCT treatment in GI cancer patients, are similar to treatment naive GI cancer patients (i.e., patients who receive adjuvant therapy); suggesting that NCT may not limit the response to immune intervention and may improve tumor responses due to the lower splenic frequency of MDSCs and higher frequency of mature T-cells.

Prognostic markers of inflammation in endometrioid and clear cell ovarian cancer

Objectives

Cancer-related systemic inflammation has been associated with prognosis in multiple cancer types. Conversely, local inflammation, which is characterized by dense intratumoral immune infiltrates, is a favorable predictor of survival outcome. However, these survival associations are not well established in ovarian cancer, particularly in the less frequent endometrioid and clear cell endometriosis associated histotypes.

Methods

This retrospective study included 119 patients (63 endometrioid and 56 clear cell ovarian carcinomas). We performed a comprehensive survival association analysis of both systemic (neutrophil-to-lymphocyte ratio or presence of endometriosis) and local inflammation markers (CD3+ and CD8+ tumor infiltrating lymphocytes) using multivariate Cox proportional hazards models that account for confounding factors.

Results

Medium to high levels of intraepithelial CD8+ tumor infiltrating lymphocytes are associated with longer survival in endometrioid ovarian cancer (p=0.04). In addition, we found that intraepithelial CD8+ tumor infiltrating lymphocytes are prognostic in clear cell ovarian cancer (p=0.02), and that intraepithelial CD3+ tumor infiltrating lymphocytes are also associated with improved outcome (p=0.02). Furthermore, intratumoral CD3+ and CD8+ tumor infiltrating lymphocytes showed improved prognosis in the endometrioid subtype (p<0.1). No prognostic value was observed for systemic immune markers.

Conclusions

In this study, patients with endometrioid and clear cell ovarian cancer with moderate to high CD8+ and CD3+ intraepithelial tumor infiltrating lymphocytes had longer overall survival. Higher expression of intratumoral CD3+ and CD8+ tumor infiltrating lymphocytes also showed an improved outcome in endometrioid ovarian cancer. In contrast, systemic inflammation, evaluated by neutrophil-to-lymphocyte ratio or presence of endometriosis, did not have a prognostic impact in these histologic subtypes.

Sequential modulation of the Wnt/β-catenin signaling pathway enhances tumor-intrinsic MHC I expression and tumor clearance

BACKGROUND

Progress in immunotherapy use for gynecologic malignancies is hampered by poor tumor antigenicity and weak T cell infiltration of the tumor microenvironment (TME). Wnt/β-catenin pathway modulation demonstrated patient benefit in clinical trials as well as enhanced immune cell recruitment in preclinical studies. The purpose of this study was to characterize the pathways by which Wnt/β-catenin modulation facilitates a more immunotherapy-favorable TME.

METHODS

Human tumor samples and in vivo patient-derived xenograft and syngeneic murine models were administered Wnt/β-catenin modulating agents DKN-01 and CGX-1321 individually or in sequence. Analytical methods included immunohistochemistry, flow cytometry, multiplex cytokine/chemokine array, and RNA sequencing.

RESULTS

DKK1 blockade via DKN-01 increased HLA/MHC expression in human and murine tissues, correlating with heightened expression of known MHC I regulators: NFkB, IL-1, LPS, and IFNy. PORCN inhibition via CGX-1321 increased production of T cell chemoattractant CXCL10, providing a mechanism for observed increases in intra-tumoral T cells. Diverse leukocyte recruitment was noted with elevations in B cells and macrophages, with increased tumor expression of population-specific chemokines. Sequential DKK1 blockade and PORCN inhibition decreased tumor burden as evidenced by reduced omental weights.

CONCLUSIONS

Wnt/β-catenin pathway modulation increases MHC I expression and promotes tumor leukocytic infiltration, facilitating a pro-immune TME associated with decreased tumor burden. This intervention overcomes common tumor immune-evasion mechanisms and may render ovarian tumors susceptible to immunotherapy.

Infiltrating T lymphocytes and programmed cell death protein-1/programmed death-ligand 1 expression in endometriosis-associated ovarian cancer

OBJECTIVE

To characterize T lymphocyte infiltration and programmed cell death protein-1 (PD-1)/programmed death-ligand 1 (PD-L1) expression in early-stage endometriosis-associated ovarian cancer (EAOC), ovarian endometriosis (OE), atypical endometriosis (AE), and deep endometriosis (DE).

DESIGN

Case-control, retrospective study.

SETTING

Research University Hospital.

PATIENT(S)

A total of 362 patients with a histologic diagnosis of EAOC, OE, AE, or DE were identified between 2000 and 2019 from Fondazione Policlinico Universitario Agostino Gemelli IRCCS and Gemelli Molise SpA tissue data banks. A 1:1 propensity score-matched method yielded matched pairs of 55 subjects with EAOC, 55 patients with OE, 12 patients with AE, and 42 patients with DE, resulting in no differences in family history of cancer, parity, and use of oral contraceptives.

INTERVENTION(S)

Immunohistochemistry assays using the following primary antibodies: CD3+; CD4+; CD8+; PD-1; and PD-L1.

MAIN OUTCOME MEASURE(S)

To characterize T lymphocyte infiltration and PD-1/PD-L1 expression in 4 different endometriosis-related diseases.

RESULT(S)

Endometriosis-associated ovarian cancer cases displayed significantly higher levels of PD-1/PD-L1 expression compared with all other endometriosis-related diseases (vs. OE vs. AE vs. DE). Moreover, a significantly lower count of infiltrating T lymphocytes was observed in EAOC cases compared with OE ones. Finally, one-third of OE cases showed a cancer-like PD-1/PD-L1 expression profile.

CONCLUSION(S)

Endometriosis-associated ovarian cancer is characterized by higher levels of PD-1/PD-L1 expression compared with benign endometriosis-related diseases. This profile was found in one-third of clinically benign cases, suggesting that it develops early in the carcinogenesis process.

Immune checkpoint inhibitors in ovarian cancer: where do we stand?

Numerous retrospective studies have demonstrated that the density of intra-tumoral immune cell infiltration is prognostic in epithelial ovarian cancer (OC). These observations together with reports of programmed death ligand-1 (PD-L1) expression in advanced OC provided the rationale for investigating the benefit of programmed death-1 (PD1) or PD-L1 inhibition in OC. Unfortunately clinical trials to date evaluating PD1/PD-L1 inhibition in patients with relapsed OC have been disappointing. In this review we will discuss early results from single agent PD1/PD-L1 inhibitors and the strategies to enhance benefit from immune-oncology agents in OC, including proposing anti-PD-L1 in combination with other agents (cytotoxics, anti-angiogenics, poly(ADP-ribose) polymerase. (PARP) inhibitors, targeted therapies or other immunotherapies), as well as evaluating these agents earlier in the disease course, or in biomarker selected patients.

Cancer-specific immune evasion and substantial heterogeneity within cancer types provide evidence for personalized immunotherapy

The immune response against cancer is orchestrated by various parameters and site-dependent specificities have been poorly investigated. In our analyses of ten different cancer types, we describe elevated infiltration by regulatory T cells as the most common feature, while other lymphocyte subsets and also expression of immune-regulatory molecules on tumor-infiltrating lymphocytes showed site-specific variation. Multiparametric analyses of these data identified similarities of renal and liver or lung with head and neck cancer. Co-expression of immune-inhibitory ligands on tumor cells was most frequent in colorectal, lung and ovarian cancer. Genes related to antigen presentation were frequently dysregulated in liver and lung cancer. Expression of co-inhibitory molecules on tumor-infiltrating T cells accumulated in advanced stages while T-cell abundance was related to enhanced expression of genes related to antigen presentation. Our results promote evaluation of cancer-specific or even personalized immunotherapeutic combinations to overcome primary or secondary resistance as major limitation of immune-checkpoint inhibition.

Cancer Immune Evasion Through Loss of MHC Class I Antigen Presentation

Major histocompatibility class I (MHC I) molecules bind peptides derived from a cell's expressed genes and then transport and display this antigenic information on the cell surface. This allows CD8 T cells to identify pathological cells that are synthesizing abnormal proteins, such as cancers that are expressing mutated proteins. In order for many cancers to arise and progress, they need to evolve mechanisms to avoid elimination by CD8 T cells. MHC I molecules are not essential for cell survival and therefore one mechanism by which cancers can evade immune control is by losing MHC I antigen presentation machinery (APM). Not only will this impair the ability of natural immune responses to control cancers, but also frustrate immunotherapies that work by re-invigorating anti-tumor CD8 T cells, such as checkpoint blockade. Here we review the evidence that loss of MHC I antigen presentation is a frequent occurrence in many cancers. We discuss new insights into some common underlying mechanisms through which some cancers inactivate the MHC I pathway and consider some possible strategies to overcome this limitation in ways that could restore immune control of tumors and improve immunotherapy.

Inflammation and immunity in ovarian cancer

The standard first-line therapy for ovarian cancer is a combination of surgery and carboplatin/paclitaxel-based chemotherapy. Patients with longer survival and improved response to chemotherapy usually present T-cell inflamed tumours. The presence of tumour-infiltrating T cells (TILs) notably varies among the different subtypes of ovarian tumours, being highest in high-grade serous ovarian carcinoma, intermediate in endometrioid tumours, and lowest in low-grade serous, mucinous and clear cell tumours. Interestingly, the presence of TILs is often accompanied by a strong immunosuppressive tumour environment. A better understanding of the immune response against ovarian cancer and the tumour immune evasion mechanisms will enable improved prognostication, response prediction and immunotherapy of this disease. This article provides an overview of some ovarian cancer cell features relevant for antitumour response, such as tumour-associated antigens, including neoantigens, expression of inhibitory molecules, and other mechanisms of immune evasion. Moreover, we describe relevant immune cell types found in epithelial ovarian tumours, including T and B lymphocytes, regulatory T cells, natural killer cells, tumour-associated macrophages, myeloid-derived suppressor cells and neutrophils. We focus on how these components influence the burden of the tumour and the clinical outcome.

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The presence of spontaneous tumour-specific T lymphocytes and the existence of multiple immune evasion mechanisms in epithelial ovarian cancer (EOC) support the immunogenicity of this tumour.

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Tumour-infiltrating T lymphocytes (TILs) have been associated with disease outcome in EOC, indicating their clinical significance.

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The subtypes of EOC, mutations in TP53 and breast and ovarian cancer susceptibility protein 1/2 and the immune expression signature are factors associated to TIL density in EOC.

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The tumour microenvironment in EOC consists of a dynamic and complex network of soluble factors, inhibitory receptors and immunosuppressive cells.

The influence of secreted factors and extracellular vesicles in ovarian cancer metastasis

Ovarian cancer cells mainly metastasise within the peritoneal cavity, the lethal consequence of tumour progression in this cancer type. Classically, changes in tumour cells, such as epithelial to mesenchymal transition, involve the down-regulatinon of E-cadherin, activation of extracellular proteases and integrin-mediated adhesion. However, our current understanding of ovarian tumour progression suggests the implication of both intrinsic and extrinsic factors. It has been proposed that ovarian cancer metastases are a consequence of the crosstalk between cancer cells and the tumour microenvironment by soluble factors and extracellular vesicles. Characterisation of the alterations in both the tumour cells and the surrounding microenvironment has emerged as a new research field to understand ovarian cancer metastasis. In this mini review, we will summarise the most recent findings, focusing our attention on the role of secreted factors and extracellular vesicles in ovarian cancer metastasis.

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During ovarian cancer metastasis, tumour cells metastasise in the mesothelium as primarily ‘soil’ for ovarian cancer ‘seeds’.

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Soluble factors and extracellular vesicles secreted by tumor cells are involved in the generation of the pre-metastatic niche.

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Cancer-associated fibroblasts (CAFs) represent the majority of stromal cells in various types of human carcinoma, including ovarian cancer.

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Analysis of early metastasis to the omentum indicates that ovarian cancer cells rely on the interaction with immune cells such as macrophages.

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Liquid biopsy analyses in ovarian cancer may help to define novel biomarkers improving patient survival and reduce lethality.

EZH2 inhibition: a promising strategy to prevent cancer immune editing

Immunotherapies are revolutionizing the clinical management of a wide range of cancers. However, intrinsic or acquired unresponsiveness to immunotherapies does occur due to the dynamic cancer immunoediting which ultimately leads to immune escape. The evolutionarily conserved histone modifier enhancer of zeste 2 (EZH2) is aberrantly overexpressed in a number of human cancers. Accumulating studies indicate that EZH2 is a main driver of cancer cells' immunoediting and mediate immune escape through downregulating immune recognition and activation, upregulating immune checkpoints and creating an immunosuppressive tumor microenvironment. In this review, we overviewed the roles of EZH2 in cancer immunoediting, the preclinical and clinical studies of current pharmacologic EZH2 inhibitors and the prospects for EZH2 inhibitor and immunotherapy combination for cancer treatment.

Preclinical and Clinical Immunotherapeutic Strategies in Epithelial Ovarian Cancer

In the past 20 years, the immune system has increasingly been recognized as a major player in tumor cell control, leading to considerable advances in cancer treatment. While promising with regards to melanoma, renal cancer and non-small cell lung cancer, immunotherapy provides, for the time being, limited success in other cancers, including ovarian cancer, potentially due to insufficient immunogenicity or to a particularly immunosuppressive microenvironment. In this review, we provide a global description of the immune context of ovarian cancer, in particular epithelial ovarian cancer (EOC). We describe the adaptive and innate components involved in the EOC immune response, including infiltrating tumor-specific T lymphocytes, B lymphocytes, and natural killer and myeloid cells. In addition, we highlight the rationale behind the use of EOC preclinical mouse models to assess resistance to immunotherapy, and we summarize the main preclinical studies that yielded anti-EOC immunotherapeutic strategies. Finally, we focus on major published or ongoing immunotherapy clinical trials concerning EOC.

Immuno-Metabolism and Microenvironment in Cancer: Key Players for Immunotherapy

Immune checkpoint inhibitors (ICIs) have changed therapeutic algorithms in several malignancies, although intrinsic and secondary resistance is still an issue. In this context, the dysregulation of immuno-metabolism plays a leading role both in the tumor microenvironment (TME) and at the host level. In this review, we summarize the most important immune-metabolic factors and how they could be exploited therapeutically. At the cellular level, an increased concentration of extracellular adenosine as well as the depletion of tryptophan and uncontrolled activation of the PI3K/AKT pathway induces an immune-tolerant TME, reducing the response to ICIs. Moreover, aberrant angiogenesis induces a hypoxic environment by recruiting VEGF, T_reg cells and immune-suppressive tumor associated macrophages (TAMs). On the other hand, factors such as gender and body mass index seem to affect the response to ICIs, while the microbiome composition (and its alterations) modulates both the response and the development of immune-related adverse events. Exploiting these complex mechanisms is the next goal in immunotherapy. The most successful strategy to date has been the combination of antiangiogenic drugs and ICIs, which prolonged the survival of patients with non-small-cell lung cancer (NSCLC) and hepatocellular carcinoma (HCC), while results from tryptophan pathway inhibition studies are inconclusive. New exciting strategies include targeting the adenosine pathway, TAMs and the microbiota with fecal microbiome transplantation.

Tumor microenvironment-related dendritic cell deficiency: a target to enhance tumor immunotherapy

Dendritic cells (DCs), as specialized antigen-presenting cells, are essential for the initiation of specific T cell responses in innate antitumor immunity and, in certain cases, support humoral responses to inhibit tumor development. Mounting evidence suggests that the DC system displays a broad spectrum of dysfunctional status in the tumor microenvironment (TME), which ultimately affects antitumor immune responses. DC-based therapy can restore the function of DCs in the TME, thus showing a promising potential in tumor therapy. In this review, we provide an overview of the DC deficiency caused by various factors in the TME and discuss proposed strategies to reverse DC deficiency and the applications of novel combinatorial DC-based therapy for immune normalization of the tumor.

Tumor core biopsies adequately represent immune microenvironment of high-grade serous carcinoma

The prognostic and therapeutic value of the tumor microenvironment (TME) in various cancer types is of major interest. Characterization of the TME often relies on a small representative tissue sample. However, the adequacy of such a sample for assessing components of the TME is not yet known. Here, we used immunohistochemical (IHC) staining and 7-color multiplex staining to evaluate CD8 (cluster of differentiation 8), CD68, PD-L1 (programmed death-ligand 1), CD34, FAP (fibroblast activation protein), and cytokeratin in 220 tissue cores from 26 high-grade serous ovarian cancer samples. Comparisons were drawn between a larger tumor specimen and smaller core biopsies based on number and location (central tumor vs. peripheral tumor) of biopsies. Our analysis found that the correlation between marker-specific cell subsets in larger tumor versus smaller core was stronger with two core biopsies and was not further strengthened with additional biopsies. Moreover, this correlation was consistently strong regardless of whether the biopsy was taken at the center or at the periphery of the original tumor sample. These findings could have a substantial impact on longitudinal assessment for detection of biomarkers in clinical trials.

Tumor-induced escape mechanisms and their association with resistance to checkpoint inhibitor therapy

Immunotherapy aims to activate the immune system to fight cancer in a very specific and targeted manner. Despite the success of different immunotherapeutic strategies, in particular antibodies directed against checkpoints as well as adoptive T-cell therapy, the response of patients is limited in different types of cancers. This attributes to escape of the tumor from immune surveillance and development of acquired resistances during therapy. In this review, the different evasion and resistance mechanisms that limit the efficacy of immunotherapies targeting tumor-associated antigens presented by major histocompatibility complex molecules on the surface of the malignant cells are summarized. Overcoming these escape mechanisms is a great challenge, but might lead to a better clinical outcome of patients and is therefore currently a major focus of research.

Small extracellular vesicles containing arginase-1 suppress T-cell responses and promote tumor growth in ovarian carcinoma

Tumor-driven immune suppression is a major barrier to successful immunotherapy in ovarian carcinomas (OvCa). Among various mechanisms responsible for immune suppression, arginase-1 (ARG1)-carrying small extracellular vesicles (EVs) emerge as important contributors to tumor growth and tumor escape from the host immune system. Here, we report that small EVs found in the ascites and plasma of OvCa patients contain ARG1. EVs suppress proliferation of CD4⁺ and CD8⁺ T-cells in vitro and in vivo in OvCa mouse models. In mice, ARG1-containing EVs are transported to draining lymph nodes, taken up by dendritic cells and inhibit antigen-specific T-cell proliferation. Increased expression of ARG1 in mouse OvCa cells is associated with accelerated tumor progression that can be blocked by an arginase inhibitor. Altogether, our studies show that tumor cells use EVs as vehicles to carry over long distances and deliver to immune cells a metabolic checkpoint molecule – ARG1, mitigating anti-tumor immune responses.

Cancer cells employ a variety of ways to escape the immune system. Here, the authors show that ovarian cancer cells produce small extracellular vescicles containing arginase 1 that are taken up by dendritic cells in the draining lymph nodes, resulting in inhibition of antigen-specific T-cell proliferation.

Understanding heterogeneous tumor microenvironment in metastatic melanoma

A systemic analysis of the tumor-immune interactions within the heterogeneous tumor microenvironment is of particular importance for understanding the antitumor immune response. We used multiplexed immunofluorescence to elucidate cellular spatial interactions and T-cell infiltrations in metastatic melanoma tumor microenvironment. We developed two novel computational approaches that enable infiltration clustering and single cell analysis-cell aggregate algorithm and cell neighborhood analysis algorithm-to reveal and to compare the spatial distribution of various immune cells relative to tumor cell in sub-anatomic tumor microenvironment areas. We showed that the heterogeneous tumor human leukocyte antigen-1 expressions differently affect the magnitude of cytotoxic T-cell infiltration and the distributions of CD20+ B cells and CD4+FOXP3+ regulatory T cells within and outside of T-cell infiltrated tumor areas. In a cohort of 166 stage III melanoma samples, high tumor human leukocyte antigen-1 expression is required but not sufficient for high T-cell infiltration, with significantly improved overall survival. Our results demonstrate that tumor cells with heterogeneous properties are associated with differential but predictable distributions of immune cells within heterogeneous tumor microenvironment with various biological features and impacts on clinical outcomes. It establishes tools necessary for systematic analysis of the tumor microenvironment, allowing the elucidation of the "homogeneous patterns" within the heterogeneous tumor microenvironment.

Targeting immune cells for cancer therapy

Recent years have seen a renaissance in the research linking inflammation and cancer with immune cells playing a central role in smouldering inflammation in the tumor microenvironment. Diverse immune cell types infiltrate the tumor microenvironment, and the dynamic tumor-immune cell interplay gives rise to a rich milieu of cytokines and growth factors. Fundamentally, this intricate cross-talk creates the conducive condition for tumor cell proliferation, survival and metastasis. Interestingly, the prominent impact of immune cells is expounded in their contrary pro-tumoral role, as well as their potential anti-cancer cellular weaponry. The latter is known as immunotherapy, a concept born out of evidence that tumors are susceptible to immune defence and that by manipulating the immune system, tumor growth can be successfully restrained. Naturally, a deeper understanding of the multifaceted roles of various immune cell types thus contributes toward developing innovative anti-cancer strategies. Therefore, in this review we first outline the roles played by the major immune cell types, such as macrophages, neutrophils, natural killer cells, T cells and B cells. We then explain the recently-explored strategies of immunomodulation and discuss some important approaches via an immunology perspective.

Identification of candidate neoantigens produced by fusion transcripts in human osteosarcomas

Osteosarcomas are characterized by highly disrupted genomes. Although osteosarcomas lack common fusions, we find evidence of many tumour specific gene-gene fusion transcripts, likely due to chromosomal rearrangements and expression of transcription-induced chimeras. Most of the fusions result in out-of-frame transcripts, potentially capable of producing long novel protein sequences and a plethora of neoantigens. To identify fusions, we explored RNA-sequencing data to obtain detailed knowledge of transcribed fusions, by creating a novel program to compare fusions identified by deFuse to de novo transcripts generated by Trinity. This allowed us to confirm the deFuse results and identify unusual splicing patterns associated with fusion events. Using various existing tools combined with this custom program, we developed a pipeline for the identification of fusion transcripts applicable as targets for immunotherapy. In addition to identifying candidate neoantigens associated with fusions, we were able to use the pipeline to establish a method for measuring the frequency of fusion events, which correlated to patient outcome, as well as highlight some similarities between canine and human osteosarcomas. The results of this study of osteosarcomas underscores the numerous benefits associated with conducting a thorough analysis of fusion events within cancer samples.

MHC/HLA Class I Loss in Cancer Cells

In this chapter I describe Tumour Immune Escape mechanisms associated with MHC/HLA class I loss in human and experimental tumours. Different altered HLA class-I phenotypes can be observed that are produced by different molecular mechanisms. Experimental and histological evidences are summarized indicating that at the early stages of tumour development there is an enormous variety of tumour clones with different MHC class I expression patterns. This phase is followed by a strong T cell mediated immune-selection of MHC/HLA class-I negative tumour cells in the primary tumour lesion. This transition period results in a formation of a tumour composed only of HLA-class I negative cells. An updated description of this process observed in a large variety of human tumors is included. In the second section I focus on MHC/HLA class I alterations observed in mouse and human metastases, and describe the generation of different tumor cell clones with altered MHC class I phenotypes, which could be similar or different from the original tumor clone. The biological and immunological relevance of these observations is discussed. Finally, the interesting phenomenon of metastatic dormancy is analyzed in association with a particular MHC class I negative tumor phenotype.

B cells in esophago-gastric adenocarcinoma are highly differentiated, organize in tertiary lymphoid structures and produce tumor-specific antibodies

Tumor-infiltrating lymphocytes (TILs) are correlated to prognosis of several kinds of cancer. Most studies focused on T cells, while the role of tumor-associated B cells (TABs) has only recently gained more attention. TABs contain subpopulations with distinct functions, potentially promoting or inhibiting immune responses. This study provides a detailed analysis of TABs in gastro-esophageal adenocarcinoma (EAC). Flow cytometric analyses of single cell suspensions of tumor samples, mucosa, lymph nodes and peripheral blood mononuclear cells (PBMC) of EAC patients and healthy controls revealed a distinct B cell compartment in cancer patients. B cells were increased in tumor samples and subset-analyses of TILs showed increased proportions of differentiated and activated B cells and an enrichment for follicular T helper cells. Confocal microscopy demonstrated that TABs were mainly organized in tertiary lymphoid structures (TLS), which resemble lymphoid follicles in secondary lymphoid organs. A panel of 34 tumor-associated antigens (TAAs) expressed in EAC was identified based on public databases and TCGA data to analyze tumor-specific B cell responses using a LUMINEXTM bead assay and flow cytometry. Structural analyses of TLS and the detection of tumor-specific antibodies against one or more TAAs in 48.1% of analyzed serum samples underline presence of anti-tumor B cell responses in EAC. Interestingly, B cells were decreased in tumors with expression of Programmed Death Ligand 1 or impaired HLA-I expression. These data demonstrate that anti-tumor B cell responses are an additional and underestimated aspect of EAC. Our results are of immediate translational relevance to emerging immunotherapies.

The Tumor Microenvironment of Epithelial Ovarian Cancer and Its Influence on Response to Immunotherapy

Immunotherapy as a treatment for cancer is a growing field of endeavor but reports of success have been limited for epithelial ovarian cancer. Overcoming the challenges to developing more effective therapeutic approaches lies in a better understanding of the factors in cancer cells and the surrounding tumor microenvironment that limit response to immunotherapies. This article provides an overview of some ovarian cancer cell features such as tumor-associated antigens, ovarian cancer-derived exosomes, tumor mutational burden and overexpression of immunoinhibitory molecules. Moreover, we describe relevant cell types found in epithelial ovarian tumors including immune cells (T and B lymphocytes, Tregs, NK cells, TAMs, MDSCs) and other components found in the tumor microenvironment including fibroblasts and the adipocytes in the omentum. We focus on how those components may influence responses to standard treatments or immunotherapies.

The Tumor Microenvironment of Epithelial Ovarian Cancer and Its Influence on Response to Immunotherapy

Immunotherapy as a treatment for cancer is a growing field of endeavor but reports of success have been limited for epithelial ovarian cancer. Overcoming the challenges to developing more effective therapeutic approaches lies in a better understanding of the factors in cancer cells and the surrounding tumor microenvironment that limit response to immunotherapies. This article provides an overview of some ovarian cancer cell features such as tumor-associated antigens, ovarian cancer-derived exosomes, tumor mutational burden and overexpression of immunoinhibitory molecules. Moreover, we describe relevant cell types found in epithelial ovarian tumors including immune cells (T and B lymphocytes, Tregs, NK cells, TAMs, MDSCs) and other components found in the tumor microenvironment including fibroblasts and the adipocytes in the omentum. We focus on how those components may influence responses to standard treatments or immunotherapies.

The Tumor Microenvironment of Epithelial Ovarian Cancer and Its Influence on Response to Immunotherapy

Immunotherapy as a treatment for cancer is a growing field of endeavor but reports of success have been limited for epithelial ovarian cancer. Overcoming the challenges to developing more effective therapeutic approaches lies in a better understanding of the factors in cancer cells and the surrounding tumor microenvironment that limit response to immunotherapies. This article provides an overview of some ovarian cancer cell features such as tumor-associated antigens, ovarian cancer-derived exosomes, tumor mutational burden and overexpression of immunoinhibitory molecules. Moreover, we describe relevant cell types found in epithelial ovarian tumors including immune cells (T and B lymphocytes, Tregs, NK cells, TAMs, MDSCs) and other components found in the tumor microenvironment including fibroblasts and the adipocytes in the omentum. We focus on how those components may influence responses to standard treatments or immunotherapies.

Ex vivo expanded tumour-infiltrating lymphocytes from ovarian cancer patients release anti-tumour cytokines in response to autologous primary ovarian cancer cells

Epithelial ovarian cancer (EOC) is the leading cause of gynaecological cancer-related death in Europe. Although most patients achieve an initial complete response with first-line treatment, recurrence occurs in more than 80% of cases. Thus, there is a clear unmet need for novel second-line treatments. EOC is frequently infiltrated with T lymphocytes, the presence of which has been shown to be associated with improved clinical outcomes. Adoptive T-cell therapy (ACT) using ex vivo-expanded tumour-infiltrating lymphocytes (TILs) has shown remarkable efficacy in other immunogenic tumours, and may represent a promising therapeutic strategy for EOC. In this preclinical study, we investigated the efficacy of using anti-CD3/anti-CD28 magnetic beads and IL-2 to expand TILs from freshly resected ovarian tumours. TILs were expanded for up to 3 weeks, and then subjected to a rapid-expansion protocol (REP) using irradiated feeder cells. Tumours were collected from 45 patients with EOC and TILs were successfully expanded from 89.7% of biopsies. Expanded CD4⁺ and CD8⁺ subsets demonstrated features associated with memory phenotypes, and had significantly higher expression of key activation and functional markers than unexpanded TILs. Expanded TILs produced anti-tumour cytokines when co-cultured with autologous tumour cells, inferring tumour cytotoxicity. Our findings demonstrate that it is possible to re-activate and expand tumour-reactive T cells from ovarian tumours. This presents a promising immunotherapy that could be used sequentially or in combination with current therapeutic strategies.

Significance of tumor-infiltrating lymphocytes before and after neoadjuvant therapy for rectal cancer

Neoadjuvant therapy for locally advanced rectal cancer is becoming increasingly common. However, biomarkers predicting the response to neoadjuvant therapy have not been established. Tumor‐infiltrating lymphocytes (TILs) have a crucial effect on tumor progression and survival outcome as the primary host immune response, and an antitumor immune effect has been reported to contribute to the response to radiotherapy and chemotherapy. We investigated the significance of TILs before and after neoadjuvant treatment and the change in the density of those TILs. Sixty‐four patients who underwent radical resection after neoadjuvant treatment for locally advanced rectal cancer were enrolled. The number of TIL subsets was examined using immunohistochemical staining of pretreatment biopsy samples and post‐treatment resected specimens. In both the neoadjuvant chemotherapy cohort and the neoadjuvant chemoradiotherapy cohort, a low density of CD8⁺TILs in pretreatment biopsy samples was associated with a poor response, and a low density of CD8⁺TILs in post‐treatment resected specimens was similarly associated with a poor response. In the neoadjuvant chemoradiotherapy cohort, the density of CD8⁺TILs in post‐treatment resected specimens was significantly increased compared with that in pretreatment biopsy samples. We concluded that T lymphocyte‐mediated immune reactions play an important role in tumor response to neoadjuvant treatment for rectal cancer, and the evaluation of TILs in pretreatment biopsy samples might be a predictor of the clinical effectiveness of neoadjuvant treatment. Furthermore, neoadjuvant therapy, especially chemoradiotherapy, could induce the activation of the local immune status.

Proteomic analysis uncovers common effects of IFN-γ and IL-27 on the HLA class I antigen presentation machinery in human cancer cells

IL-27, a member of the IL-12-family of cytokines, has shown anti-tumor activity in several pre-clinical models due to anti-proliferative, anti-angiogenic and immune-enhancing effects. On the other hand, IL-27 demonstrated immune regulatory activities and inhibition of auto-immunity in mouse models. Also, we reported that IL-27, similar to IFN-γ, induces the expression of IL-18BP, IDO and PD-L1 immune regulatory molecules in human cancer cells. Here, a proteomic analysis reveals that IL-27 and IFN-γ display a broad overlap of functions on human ovarian cancer cells. Indeed, among 990 proteins modulated by either cytokine treatment in SKOV3 cells, 814 showed a concordant modulation by both cytokines, while a smaller number (176) were differentially modulated. The most up-regulated proteins were common to both IFN-γ and IL-27. In addition, functional analysis of IL-27-regulated protein networks highlighted pathways of interferon signaling and regulation, antigen presentation, protection from natural killer cell-mediated cytotoxicity, regulation of protein polyubiquitination and proteasome, aminoacid catabolism and regulation of viral protein levels.

Importantly, we found that IL-27 induced HLA class I molecule expression in human cancer cells of different histotypes, including tumor cells showing very low expression. IL-27 failed only in a cancer cell line bearing a homozygous deletion in the B2M gene. Altogether, these data point out to a broad set of activities shared by IL-27 and IFN-γ, which are dependent on the common activation of the STAT1 pathway. These data add further explanation to the anti-tumor activity of IL-27 and also to its dual role in immune regulation.

Dose-Response Association of CD8+ Tumor-Infiltrating Lymphocytes and Survival Time in High-Grade Serous Ovarian Cancer

Importance

Cytotoxic CD8+ tumor-infiltrating lymphocytes (TILs) participate in immune control of epithelial ovarian cancer; however, little is known about prognostic patterns of CD8+ TILs by histotype and in relation to other clinical factors.

Objective

To define the prognostic role of CD8+ TILs in epithelial ovarian cancer.

Design, Setting, and Participants

This was a multicenter observational, prospective survival cohort study of the Ovarian Tumor Tissue Analysis Consortium. More than 5500 patients, including 3196 with high-grade serous ovarian carcinomas (HGSOCs), were followed prospectively for over 24 650 person-years.

Exposures

Following immunohistochemical analysis, CD8+ TILs were identified within the epithelial components of tumor islets. Patients were grouped based on the estimated number of CD8+ TILs per high-powered field: negative (none), low (1-2), moderate (3-19), and high (≥20). CD8+ TILs in a subset of patients were also assessed in a quantitative, uncategorized manner, and the functional form of associations with survival was assessed using penalized B-splines.

Main Outcomes and Measures

Overall survival time.

Results

The final sample included 5577 women; mean age at diagnosis was 58.4 years (median, 58.2 years). Among the 5 major invasive histotypes, HGSOCs showed the most infiltration. CD8+ TILs in HGSOCs were significantly associated with longer overall survival; median survival was 2.8 years for patients with no CD8+ TILs and 3.0 years, 3.8 years, and 5.1 years for patients with low, moderate, or high levels of CD8+ TILs, respectively (P value for trend = 4.2 × 10−16). A survival benefit was also observed among women with endometrioid and mucinous carcinomas, but not for those with the other histotypes. Among HGSOCs, CD8+ TILs were favorable regardless of extent of residual disease following cytoreduction, known standard treatment, and germline BRCA1 pathogenic mutation, but were not prognostic for BRCA2 mutation carriers. Evaluation of uncategorized CD8+ TIL counts showed a near-log-linear functional form.

Conclusions and Relevance

This study demonstrates the histotype-specific nature of immune infiltration and provides definitive evidence for a dose-response relationship between CD8+ TILs and HGSOC survival. That the extent of infiltration is prognostic, not merely its presence or absence, suggests that understanding factors that drive infiltration will be the key to unraveling outcome heterogeneity in this cancer.

Dose-Response Association of CD8+ Tumor-Infiltrating Lymphocytes and Survival Time in High-Grade Serous Ovarian Cancer

Importance

Cytotoxic CD8+ tumor-infiltrating lymphocytes (TILs) participate in immune control of epithelial ovarian cancer; however, little is known about prognostic patterns of CD8+ TILs by histotype and in relation to other clinical factors.

Objective

To define the prognostic role of CD8+ TILs in epithelial ovarian cancer.

Design, Setting, and Participants

This was a multicenter observational, prospective survival cohort study of the Ovarian Tumor Tissue Analysis Consortium. More than 5500 patients, including 3196 with high-grade serous ovarian carcinomas (HGSOCs), were followed prospectively for over 24 650 person-years.

Exposures

Following immunohistochemical analysis, CD8+ TILs were identified within the epithelial components of tumor islets. Patients were grouped based on the estimated number of CD8+ TILs per high-powered field: negative (none), low (1-2), moderate (3-19), and high (≥20). CD8+ TILs in a subset of patients were also assessed in a quantitative, uncategorized manner, and the functional form of associations with survival was assessed using penalized B-splines.

Main Outcomes and Measures

Overall survival time.

Results

The final sample included 5577 women; mean age at diagnosis was 58.4 years (median, 58.2 years). Among the 5 major invasive histotypes, HGSOCs showed the most infiltration. CD8+ TILs in HGSOCs were significantly associated with longer overall survival; median survival was 2.8 years for patients with no CD8+ TILs and 3.0 years, 3.8 years, and 5.1 years for patients with low, moderate, or high levels of CD8+ TILs, respectively (P value for trend = 4.2 × 10−16). A survival benefit was also observed among women with endometrioid and mucinous carcinomas, but not for those with the other histotypes. Among HGSOCs, CD8+ TILs were favorable regardless of extent of residual disease following cytoreduction, known standard treatment, and germline BRCA1 pathogenic mutation, but were not prognostic for BRCA2 mutation carriers. Evaluation of uncategorized CD8+ TIL counts showed a near-log-linear functional form.

Conclusions and Relevance

This study demonstrates the histotype-specific nature of immune infiltration and provides definitive evidence for a dose-response relationship between CD8+ TILs and HGSOC survival. That the extent of infiltration is prognostic, not merely its presence or absence, suggests that understanding factors that drive infiltration will be the key to unraveling outcome heterogeneity in this cancer.

Dose-Response Association of CD8+ Tumor-Infiltrating Lymphocytes and Survival Time in High-Grade Serous Ovarian Cancer

Importance

Cytotoxic CD8+ tumor-infiltrating lymphocytes (TILs) participate in immune control of epithelial ovarian cancer; however, little is known about prognostic patterns of CD8+ TILs by histotype and in relation to other clinical factors.

Objective

To define the prognostic role of CD8+ TILs in epithelial ovarian cancer.

Design, Setting, and Participants

This was a multicenter observational, prospective survival cohort study of the Ovarian Tumor Tissue Analysis Consortium. More than 5500 patients, including 3196 with high-grade serous ovarian carcinomas (HGSOCs), were followed prospectively for over 24 650 person-years.

Exposures

Following immunohistochemical analysis, CD8+ TILs were identified within the epithelial components of tumor islets. Patients were grouped based on the estimated number of CD8+ TILs per high-powered field: negative (none), low (1-2), moderate (3-19), and high (≥20). CD8+ TILs in a subset of patients were also assessed in a quantitative, uncategorized manner, and the functional form of associations with survival was assessed using penalized B-splines.

Main Outcomes and Measures

Overall survival time.

Results

The final sample included 5577 women; mean age at diagnosis was 58.4 years (median, 58.2 years). Among the 5 major invasive histotypes, HGSOCs showed the most infiltration. CD8+ TILs in HGSOCs were significantly associated with longer overall survival; median survival was 2.8 years for patients with no CD8+ TILs and 3.0 years, 3.8 years, and 5.1 years for patients with low, moderate, or high levels of CD8+ TILs, respectively (P value for trend = 4.2 × 10−16). A survival benefit was also observed among women with endometrioid and mucinous carcinomas, but not for those with the other histotypes. Among HGSOCs, CD8+ TILs were favorable regardless of extent of residual disease following cytoreduction, known standard treatment, and germline BRCA1 pathogenic mutation, but were not prognostic for BRCA2 mutation carriers. Evaluation of uncategorized CD8+ TIL counts showed a near-log-linear functional form.

Conclusions and Relevance

This study demonstrates the histotype-specific nature of immune infiltration and provides definitive evidence for a dose-response relationship between CD8+ TILs and HGSOC survival. That the extent of infiltration is prognostic, not merely its presence or absence, suggests that understanding factors that drive infiltration will be the key to unraveling outcome heterogeneity in this cancer.

The prognostic value of tumor-infiltrating T lymphocytes in ovarian cancer

The prognostic value of tumor-infiltrating lymphocytes (TILs) in ovarian cancer is still in controversial. This study is aimed to assess the impact of different TIL subsets on the progression free survival (PFS)/disease free survival (DSS) and overall survival (OS)/disease specific survival (DSS) in ovarian cancer. A comprehensive literature search in PubMed, ISI Web of Science, and Medline was performed to identify relevant studies evaluating the prognostic value of TILs in ovarian cancer. Reviews of each study were conducted and data were extracted. The main outcomes analyzed were PFS/DFS and OS/DSS. A total of 21 eligible studies enrolling 2903 ovarian cancer patients were included for the meta-analysis. The overall analysis revealed that intraepithelial CD3⁺ and CD8⁺ TILs were strongly associated with improved PFS/DFS (HR=0.53, for CD3⁺ TILs; and HR=0.50, for CD8⁺ TILs). Intraepithelial CD8⁺/Foxp3⁺ ratios appeared to be associated with improved PFS, though without reaching statistical significance (HR=0.73). Moreover, intraepithelial CD3⁺, CD8⁺, and CD103⁺ TILs were clearly associated with increased OS/DSS (HR=0.50, for CD3⁺ TILs; HR=0.62, for CD8⁺ TILs; HR=0.54, for CD103⁺ TILs). However, intraepithelial FoxP3⁺ TILs, CD8⁺/FoxP3⁺ ratios, CD8⁺/CD4⁺ ratios, and stromal TILs had no impact on the OS/DSS (HR=0.98, for FoxP3+ TILs; HR=0.69, for CD8⁺/FoxP3⁺ ratios; HR=0.48, for CD8⁺/CD4⁺ ratios; HR=0.82, for stromal TILs). In conclusion, the present meta-analysis supports the hypothesis that intraepithelial TILs are predictive biomarkers for the prognosis of ovarian cancer patients. Future randomized studies are needed to verify these observations.

CAR-T cell therapy in ovarian cancer: from the bench to the bedside

Ovarian cancer (OC) is the most lethal gynecological malignancy and is responsible for most gynecological cancer deaths. Apart from conventional surgery, chemotherapy, and radiotherapy, chimeric antigen receptor-modified T (CAR-T) cells as a representative of adoptive cellular immunotherapy have received considerable attention in the research field of cancer treatment. CARs combine antigen specificity and T-cell-activating properties in a single fusion molecule. Several preclinical experiments and clinical trials have confirmed that adoptive cell immunotherapy using typical CAR-engineered T cells for OC is a promising treatment approach with striking clinical efficacy; moreover, the emerging CAR-Ts targeting various antigens also exert great potential. However, such therapies have side effects and toxicities, such as cytokine-associated and “on-target, off-tumor” toxicities. In this review, we systematically detail and highlight the present knowledge of CAR-Ts including the constructions, vectors, clinical applications, development challenges, and solutions of CAR-T-cell therapy for OC. We hope to provide new insight into OC treatment for the future.

The role of membrane transporters in ovarian cancer chemoresistance and prognosis

INTRODUCTION

Ovarian cancer has the highest mortality rate of all cancers in women. There is currently no effective method for early diagnosis, limiting the precision of clinical expectations. Predictions of therapeutic efficacy are currently not available either. Specifically, the development of chemoresistance against conventional chemotherapy poses a fundamental complication. Some membrane transporters have been reported to influence chemoresistance, which is often associated with a poor prognosis. Areas covered: The aim of this article is to review the existing information about membrane transporters and their role in both ovarian cancer chemoresistance and its outcomes. We then highlight limitations of current methodologies and suggest alternatives providing avenues for future research. Expert opinion: Membrane transporters play an important role in development of chemoresistance and affect prognosis of ovarian cancer patients; however, due to variations in methodology and in patient populations, their specific roles have yet to be clarified. For further evaluation of the clinical utility of membrane transporters, it is essential to validate results and improve methods for marker assessment across laboratories. A promising area for future research is to identify the genetic variability in potential markers in peripheral blood. These markers would then stratify patients into defined groups for optimal intervention.

DMBT1 expression in biliary carcinogenesis with correlation of clinicopathological data

AIMS

Deleted in malignant brain tumours 1 (DMBT1) exerts functions in the regulation of epithelial differentiation and inflammation and has been proposed as a tumour suppressor. Because chronic inflammation is a hallmark of cholangiocarcinogenesis, the aim of this study was to investigate the expression of DMBT1 in biliary tract cancer (BTC) and to correlate this expression with clinicopathological data.

METHODS AND RESULTS

The expression of DMBT1 protein was examined immunohistochemically in 157 BTC patients [41 intrahepatic (ICC), 60 extrahepatic cholangiocarcinomas (ECC) and 56 adenocarcinomas of the gallbladder (GBAC)]. Additionally, 56 samples of high-grade biliary intraepithelial neoplasia (BilIN 3) and 92 corresponding samples of histological non-neoplastic biliary tract tissues were included. DMBT1 expression was increased significantly in BilIN 3 compared to normal tissue (P < 0.0001) and BTC (P < 0.0001). BTC showed no significant difference in DMBT1 expression compared to non-neoplastic biliary tissue (P = 0.315). Absent DMBT1 expression in non-neoplastic biliary tissue of BTC patients was associated with poorer survival (P = 0.027). DMBT1 expression was correlated significantly with patients' age (P < 0.001).

CONCLUSION

DMBT1 is expressed differently in cholangiocarcinogenesis and poorer patients' survival rates are associated with absent DMBT1 expression in non-neoplastic biliary tissue, suggesting a tumour-suppressive role of DMBT1 in early cholangiocarcinogenesis.