Immunosuppression through constitutively activated NF-κB signalling in human ovarian cancer and its reversal by an NF-κB inhibitor

Tumor eradication by triplet therapy with BRAF inhibitor, TLR 7 agonist, and PD-1 antibody for BRAF-mutated melanoma

Programmed death 1 (PD-1)/programmed death-ligand 1 inhibitors are commonly used to treat various cancers, including melanoma. However, their efficacy as monotherapy is limited, and combination immunotherapies are being explored to improve outcomes. In this study, we investigated a combination immunotherapy involving an anti-PD-1 antibody that blocks the major adaptive immune-resistant mechanisms, a BRAF inhibitor that inhibits melanoma cell proliferation, and multiple primary immune-resistant mechanisms, such as cancer cell-derived immunosuppressive cytokines, and a Toll-like receptor 7 agonist that enhances innate immune responses that promote antitumor T-cell induction and functions. Using a xenogeneic nude mouse model implanted with human BRAF-mutated melanoma, a BRAF inhibitor vemurafenib was found to restore T-cell-stimulatory activity in conventional dendritic cells by reducing immunosuppressive cytokines, including interleukin 6, produced by human melanoma. Additionally, intravenous administration of the Toll-like receptor 7 agonist DSR6434 enhanced tumor growth inhibition by vemurafenib through stimulating the plasmacytoid dendritic cells/interferon-α/natural killer cell pathways and augmenting the T-cell-stimulatory activity of conventional dendritic cells. In a syngeneic mouse model implanted with murine BRAF-mutated melanoma, the vemurafenib and DSR6434 combination synergistically augmented the induction of melanoma antigen gp100-specific T cells and inhibited tumor growth. Notably, only triplet therapy with vemurafenib, DSR6434, and the anti-PD-1 antibody resulted in complete regression of SIY antigen-transduced BRAF-mutated melanoma in a CD8 T-cell-dependent manner. These findings indicate that a triple-combination strategy targeting adaptive and primary resistant mechanisms while enhancing innate immune responses that promote tumor-specific T cells may be crucial for effective tumor eradication.

Drug resistance in ovarian cancer: from mechanism to clinical trial

Ovarian cancer is the leading cause of gynecological cancer-related death. Drug resistance is the bottleneck in ovarian cancer treatment. The increasing use of novel drugs in clinical practice poses challenges for the treatment of drug-resistant ovarian cancer. Continuing to classify drug resistance according to drug type without understanding the underlying mechanisms is unsuitable for current clinical practice. We reviewed the literature regarding various drug resistance mechanisms in ovarian cancer and found that the main resistance mechanisms are as follows: abnormalities in transmembrane transport, alterations in DNA damage repair, dysregulation of cancer-associated signaling pathways, and epigenetic modifications. DNA methylation, histone modifications and noncoding RNA activity, three key classes of epigenetic modifications, constitute pivotal mechanisms of drug resistance. One drug can have multiple resistance mechanisms. Moreover, common chemotherapies and targeted drugs may have cross (overlapping) resistance mechanisms. MicroRNAs (miRNAs) can interfere with and thus regulate the abovementioned pathways. A subclass of miRNAs, "epi-miRNAs", can modulate epigenetic regulators to impact therapeutic responses. Thus, we also reviewed the regulatory influence of miRNAs on resistance mechanisms. Moreover, we summarized recent phase I/II clinical trials of novel drugs for ovarian cancer based on the abovementioned resistance mechanisms. A multitude of new therapies are under evaluation, and the preliminary results are encouraging. This review provides new insight into the classification of drug resistance mechanisms in ovarian cancer and may facilitate in the successful treatment of resistant ovarian cancer.

Sindbis Virus Vaccine Platform: A Promising Oncolytic Virus-Mediated Approach for Ovarian Cancer Treatment

This review article provides a comprehensive overview of a novel Sindbis virus vaccine platform as potential immunotherapy for ovarian cancer patients. Ovarian cancer is the most lethal of all gynecological malignancies. The majority of high-grade serous ovarian cancer (HGSOC) patients are diagnosed with advanced disease. Current treatment options are very aggressive and limited, resulting in tumor recurrences and 50-60% patient mortality within 5 years. The unique properties of armed oncolytic Sindbis virus vectors (SV) in vivo have garnered significant interest in recent years to potently target and treat ovarian cancer. We discuss the molecular biology of Sindbis virus, its mechanisms of action against ovarian cancer cells, preclinical in vivo studies, and future perspectives. The potential of Sindbis virus-based therapies for ovarian cancer treatment holds great promise and warrants further investigation. Investigations using other oncolytic viruses in preclinical studies and clinical trials are also presented.

The Role of NF-κB in Endometrial Diseases in Humans and Animals: A Review

The expression of genes of various proinflammatory chemokines and cytokines is controlled, among others, by the signaling pathway of the nuclear factor kappaB (NF-κB) superfamily of proteins, providing an impact on immune system functioning. The present review addresses the influence and role of the NF-κB pathway in the development and progression of most vital endometrial diseases in human and animal species. Immune modulation by NF-κB in endometritis, endometrosis, endometriosis, and carcinoma results in changes in cell migration, proliferation, and inflammation intensity in both the stroma and epithelium. In endometrial cells, the NF-κB signaling pathway may be activated by multiple stimuli, such as bacterial parts, cytokines, or hormones binding to specific receptors. The dysregulation of the immune system in response to NF-κB involves aberrant production of chemokines and cytokines, which plays a role in endometritis, endometriosis, endometrosis, and endometrial carcinoma. However, estrogen and progesterone influence on the reproductive tract always plays a major role in its regulation. Thus, sex hormones cannot be overlooked in endometrial disease physiopathology. While immune system dysregulation seems to be NF-κB-dependent, the hormone-independent and hormone-dependent regulation of NF-κB signaling in the endometrium should be considered in future studies. Future goals in this research should be a step up into clinical trials with compounds affecting NF-κB as treatment for endometrial diseases.

Tumor PKCδ instigates immune exclusion in EGFR-mutated non-small cell lung cancer

BACKGROUND

The recruitment of a sufficient number of immune cells to induce an inflamed tumor microenvironment (TME) is a prerequisite for effective response to cancer immunotherapy. The immunological phenotypes in the TME of EGFR-mutated lung cancer were characterized as non-inflamed, for which immunotherapy is largely ineffective.

METHODS

Global proteomic and phosphoproteomic data from lung cancer tissues were analyzed aiming to map proteins related to non-inflamed TME. The ex vivo and in vivo studies were carried out to evaluate the anti-tumor effect. Proteomics was applied to identify the potential target and signaling pathways. CRISPR-Cas9 was used to knock out target genes. The changes of immune cells were monitored by flow cytometry. The correlation between PKCδ and PD-L1 was verified by clinical samples.

RESULTS

We proposed that PKCδ, a gatekeeper of immune homeostasis with kinase activity, is responsible for the un-inflamed phenotype in EGFR-mutated lung tumors. It promotes tumor progression by stimulating extracellular matrix (ECM) and PD-L1 expression which leads to immune exclusion and assists cancer cell escape from T cell surveillance. Ablation of PKCδ enhances the intratumoral penetration of T cells and suppresses the growth of tumors. Furthermore, blocking PKCδ significantly sensitizes the tumor to immune checkpoint blockade (ICB) therapy (αPD-1) in vitro and in vivo model.

CONCLUSIONS

These findings revealed that PKCδ is a critical switch to induce inflamed tumors and consequently enhances the efficacy of ICB therapy in EGFR-mutated lung cancer. This opens a new avenue for applying immunotherapy against recalcitrant tumors.

Gene polymorphisms of interleukin 10 (− 819 C/T and − 1082 G/A) in women with ovarian cancer

Background

Ovarian cancer (OC) is the leading cause of death associated with gynecologic cancer. IL-10 plays an important role in tumorigenesis. We investigated IL-10 gene polymorphisms in OC patients. The current case–control study screened forty-eight women with OC and forty-eight healthy women who did not have OC. The genotyping of SNPs (− 1082 G > A; rs1800896 and − 819 C > T; rs1800871) of the IL-10 gene was done by tetra primers sequence-specific primer polymerase chain reaction (SSP-PCR) technique. The plasma levels of IL-10 were measured using an enzyme-linked immunosorbent assay (ELISA).

Results

For IL-10 (− 1082 G/A) polymorphism, the G (wild allele) was significantly associated with increasing the risk of OC (OR = 2.054 with CI = 1.154–3.657; P < 0.05), while the A (variant allele) and AA genotype was significantly associated with decreasing the risk of OC (OR = 0.487 with CI = 0.273–0.867; P < 0.05) and (OR = 0.15; 95% CI = 0.04–0.63; P < 0.05), respectively. For IL-10 (− 819C/T) polymorphisms, the T allele (variant allele) and (TT, CT genotypes) were significantly associated with increasing the risk of OC (OR = 2.800 with 95% CI = 1.577–5.037; P < 0.05), (OR = 18.33 with 95% CI = 3.46–97.20; P < 0.001), and (OR = 9.44 with 95% CI = 2.52–35.40; P < 0.001), respectively, while the C (wild allele) was significantly associated with decreasing the risk of OC (OR = 0.357 with 95% CI = 0.199–0.642; P < 0.05). The haplotype analysis for (− 1082 G > A and − 819 C > T shows the GT haplotype was significantly associated with increasing the risk of OC (OR = 50.09 with CI = 6.34–395.92; P < 0.001). OC was substantially correlated with IL-10 level (r = 0.457; p < 0.001). There is no linkage disequilibrium (LD) between IL 10 − 1082 G/A and IL 10 − 819 C/T (D′ = 0.1315, r2 = 0.016; P = NS). A statistically significant positive relationship existed between IL-10 and CA125 and ALT (P < 0.05). IL-10 and albumin showed a strong negative association (P < 0.05), whereas the correlation of IL10 plasma level with BUN, AST, T. Bil., TLC, PLT, Cr., and HB has not any significant value (P > 0.05).

Conclusions

Overall, this study supports an association of IL-10 (− 1082 G/A and − 819C/T) polymorphisms with the risk of ovarian cancer.

The role of nanomaterials in enhancing natural product translational potential and modulating endoplasmic reticulum stress in the treatment of ovarian cancer

Ovarian cancer, and particularly its most frequent type, epithelial ovarian carcinoma, constitutes one of the most dangerous malignant tumors among females. Substantial evidence has described the potential of phytochemicals against ovarian cancer. The effect of natural compounds on endoplasmic reticulum (ER) stress is of great relevance in this regard. In ovarian cancer, the accumulation of misfolded proteins in the ER lumen results in decompensated ER stress. This leads to deregulation in the physiological processes for the posttranslational modification of proteins, jeopardizes cellular homeostasis, and increases apoptotic signaling. Several metabolites and metabolite extracts of phytochemical origin have been studied in the context of ER stress in ovarian cancer. Resveratrol, quercetin, curcumin, fucosterol, cleistopholine, fucoidan, and epicatechin gallate, among others, have shown inhibitory potential against ER stress. The chemical structure of each compound plays an important role concerning its pharmacodynamics, pharmacokinetics, and overall effectiveness. Studying and cross-comparing the chemical features that render different phytochemicals effective in eliciting particular anti-ER stress actions can help improve drug design or develop multipotent combination regimens. Many studies have also investigated the properties of formulations such as nanoparticles, niosomes, liposomes, and intravenous hydrogel based on curcumin and quercetin along with some other phytomolecules in ovarian cancer. Overall, the potential of phytochemicals in targeting genetic mechanisms of ovarian cancer warrants further translational and clinical investigation.

NF-κB Signaling in Tumor Pathways Focusing on Breast and Ovarian Cancer

Immune disorders and cancer share a common pathway involving NF-κb signaling. Through involvement with GM-CSF, NF-κB can contribute to proliferation and activation of T- and B- cells as well as immune cell migration to sites of inflammation. In breast cancer, this signaling pathway has been linked to resistance with endocrine and chemotherapies. Similarly, in ovarian cancer, NF-κB influences angiogenesis and inflammation pathways. Further, BRCA1 signaling common to both breast and ovarian cancer also has the capability to induce NF-κB activity. Immunotherapy involving NF-κB can also be implemented to combat chemoresistance. The complex signaling pathways of NF-κB can be harnessed for developing cancer therapeutics to promote immunotherapy for improving patient outcomes.

Sintilimab combined with bevacizumab in relapsed/persistent ovarian clear cell carcinoma (INOVA): an investigator-initiated, multicentre clinical trial-a study protocol of clinical trial

BACKGROUND

Ovarian clear cell carcinoma (OCCC) has an abysmal prognosis with a median overall survival (OS) of 25.3 months because of a low response to chemotherapy. The 5-year disease-specific survival rate after recurrence is 13.2%, with more than two-thirds of the patients dying within a year. Therefore, it is urgent to explore new therapeutic options for OCCC. Based on the characteristic immune-suppressive tumour microenvironment derived from the gene expression profile of OCCC, the combination of immunoantiangiogenesis therapy might have certain efficacy in recurrent/persistent OCCC. This trial aims to evaluate the efficacy and safety of sintilimab and bevacizumab in patients who have failed platinum-containing chemotherapy with recurrent or persistent OCCC.

METHOD AND ANALYSIS

In this multicentre, single-arm, open-label, investigator-initiated clinical trial, 38 patients will be assigned to receive sintilimab 200 mg plus bevacizumab 15 mg/kg every 3 weeks. The eligibility criteria include histologically diagnosed patients with recurrent or persistent OCCC who have been previously treated with at least one-line platinum-containing chemotherapy; patients with Eastern Cooperative Oncology Group (ECOG) performance status 0-2 with an expected survival greater than 12 weeks. The exclusion criteria include patients previously treated with immune checkpoint inhibitor and patients with contraindications of bevacizumab and sintilimab. The primary endpoint is the objective response rate. The secondary endpoints are progression-free survival, time to response, duration of response, disease control rate, OS, safety and quality of life. Statistical significance was defined as p<0.05.

ETHICS AND DISSEMINATION

This trial was approved by the Research Ethics Commission of Tongji Medical College of Huazhong University of Science and Technology (2020-S337). The protocol of this study is registered at www.

CLINICALTRIALS

gov. The trial results will be published in peer-reviewed journals and at conferences.

TRIAL REGISTRATION NUMBER

NCT04735861; Clinicaltrials. gov.

Synergistic effect of Abraxane that combines human IL15 fused with an albumin-binding domain on murine models of pancreatic ductal adenocarcinoma

Nab‐paclitaxel (Abraxane), which is a nanoparticle form of albumin‐bound paclitaxel, is one of the standard chemotherapies for pancreatic ductal adenocarcinoma (PDAC). This study determined the effect of Abraxane in combination with a fusion protein, hIL15‐ABD, on subcutaneous Panc02 and orthotopic KPC C57BL/6 murine PDAC models. Abraxane combined with hIL15‐ABD best suppressed tumour growth and produced a 40%–60% reduction in the tumour size for Panc02 and KPC, compared to the vehicle group. In the combination group, the active form of interferon‐γ (IFN‐γ)‐secreting CD8⁺ T cells and CD11b⁺CD86⁺ M1 macrophages in tumour infiltrating lymphocytes (TILs) were increased. In the tumour drainage lymph nodes (TDLNs) of the combination group, there was a 18% reduction in CD8⁺IFN‐γ⁺ T cells and a 0.47% reduction in CD4⁺CD25⁺FOXP3⁺ regulatory T cells, as opposed to 5.0% and 5.1% reductions, respectively, for the control group. Superior suppression of CD11b⁺GR‐1⁺ myeloid‐derived suppressor cells (MDSCs) and the induction of M1 macrophages in the spleen and bone marrow of mice were found in the combination group. Abraxane and hIL15‐ABD effectively suppressed NF‐κB‐mediated immune suppressive markers, including indoleamine 2,3‐dioxygenase (IDO), Foxp3 and VEGF. In conclusion, Abraxane combined with hIL15‐ABD stimulates the anticancer activity of effector cells, inhibits immunosuppressive cells within the tumour microenvironment (TME) of PDAC, and produces a greater inhibitory effect than individual monotherapies.

Nano-immunotherapeutics: targeting approach as strategic regulation at tumor microenvironment for cancer treatment

Cancer is the leading cause of mortality worldwide, which necessitates our consideration related to novel treatment approach. Tumor cells at the tumor microenvironment (TME), regulate a plethora of key mechanistic signaling pathways that obstruct antitumor immune responses by immune suppression, immune resistance or acquired immune tolerance. The present therapeutic regimes are provided independently or in combination, or as immunotherapies for cancer immune targeting. Immunotherapy has altered the arena of oncology and patient care. By using the host immune system, the immunostimulatory molecules can exert a robust, personalized response against the patient’s own tumors. Alternatively, tumors may exploit these strategies to escape immune recognition, and accordingly, such mechanisms represent chances for immunotherapy intervention. Nonetheless, despite promising outcomes from immunotherapies in recurrent and metastatic cancers, immune-therapeutics in clinics has been limited owing to unpredictability in the produced immune response and reported instances of immune-related adverse effects. The unrealized potential of immunotherapies in cancer management maybe due to the obstacles such as heterogeneous nature, multiple targets, patients’ immune response, specificity for cancer or variability in response generation in toxicity levels, delivery and cost related to therapeutics etc. Further revolutionary trends related to immunotherapies are noticeable with slower progress for cancer management. Recent advances in nanomedicine strategize to ameliorate the lacuna of immunotherapy as it relies on the inherent biophysical characteristics of nanocarriers: size, shape, surface charge and multifunctionality and exploiting them as first line therapy for delivery of biomolecules, single checkpoint inhibitors and for imaging of TME. Therefore, nano-assisted immunotherapies can boost the immunotherapeutic approach, overcoming factors that are with imminent potential risks related to it, thereby significantly improving the survival rate associated with it in cancer patients. Nanotechnology is anticipated to overcome the confines of existing cancer immunotherapy and to successfully combine various cancer treatment modes.

NSAIDs and Cancer Resolution: New Paradigms beyond Cyclooxygenase

Acute inflammation or resolved inflammation is an adaptive host defense mechanism and is self-limiting, which returns the body to a state of homeostasis. However, unresolved, uncontrolled, or chronic inflammation may lead to various maladies, including cancer. Important evidence that links inflammation and cancer is that nonsteroidal anti-inflammatory drugs (NSAIDs), such as aspirin, reduce the risk and mortality from many cancers. The fact that NSAIDs inhibit the eicosanoid pathway prompted mechanistic drug developmental work focusing on cyclooxygenase (COX) and its products. The increased prostaglandin E2 levels and the overexpression of COX-2 in the colon and many other cancers provided the rationale for clinical trials with COX-2 inhibitors for cancer prevention or treatment. However, NSAIDs do not require the presence of COX-2 to prevent cancer. In this review, we highlight the effects of NSAIDs and selective COX-2 inhibitors (COXIBs) on targets beyond COX-2 that have shown to be important against many cancers. Finally, we hone in on specialized pro-resolving mediators (SPMs) that are biosynthesized locally and, in a time, -dependent manner to promote the resolution of inflammation and subsequent tissue healing. Different classes of SPMs are reviewed, highlighting aspirin's potential in triggering the production of these resolution-promoting mediators (resolvins, lipoxins, protectins, and maresins), which show promise in inhibiting cancer growth and metastasis.

DHMEQ enhances the cytotoxic effect of cisplatin and carboplatin in ovarian cancer cell lines

Ovarian cancer (OvCa) is one of the most lethal gynaecological malignancies. It is diagnosed mostly in advanced stages. Due to a lack of appropriate early detection markers and non-ambiguous symptoms, the five-year survival rate is significantly reduced. Despite a primary good response to platinum-based therapy, approximately 70% of patients will develop a chemoresistance phenotype. The activation of the NF-κB signalling pathway plays a crucial role in this process. It is responsible for increasing cell viability, cell cycle progression and induces growth and migration of neoplastic cells. A few independent studies have yet suggested a high correlation between activation of NF-κB and poor outcome in OvCa patients. Thus, developing inhibitors of the NF-κB pathway has become a new target of cancer therapies. One of the promising compounds is DHMEQ (dehydroxymethylepoxyquinomicin). Our preliminary studies indicated that DHMEQ combined with cisplatin (CDDP) or carboplatin (CBP) enhanced apoptosis in the A2780 cell line and caused cell cycle arrest in the G2/M phase in the SKOV3 cell line, but not in the normal cell line MRC-5 pd19. Moreover, the combination of those agents caused decreased motility of cells, especially with the CBP. However, the invasion of cells was not changed significantly. The analysis of drug interactions using CompuSyn software has revealed that observed effect of the doses used in the study was antagonistic, but the DRI guidelines and in vitro observation of biological response indicate that a combination of DHMEQ with CDDP or CBP could be a novel proposal in ovarian cancer treatment.

Tumor-immune profiling of CT-26 and Colon 26 syngeneic mouse models reveals mechanism of anti-PD-1 response

BACKGROUND

Immune checkpoint blockade (ICB) therapies have changed the paradigm of cancer therapies. However, anti-tumor response of the ICB is insufficient for many patients and limited to specific tumor types. Despite many preclinical and clinical studies to understand the mechanism of anti-tumor efficacy of ICB, the mechanism is not completely understood. Harnessing preclinical tumor models is one way to understand the mechanism of treatment response.

METHODS

In order to delineate the mechanisms of anti-tumor activity of ICB in preclinical syngeneic tumor models, we selected two syngeneic murine colorectal cancer models based on in vivo screening for sensitivity with anti-PD-1 therapy. We performed tumor-immune profiling of the two models to identify the potential mechanism for anti-PD-1 response.

RESULTS

We performed in vivo screening for anti-PD-1 therapy across 23 syngeneic tumor models and found that CT-26 and Colon 26, which are murine colorectal carcinoma derived from BALB/c mice, showed different sensitivity to anti-PD-1. CT-26 tumor mice were more sensitive to the anti-PD-1 antibody than Colon 26, while both models show similarly sensitivity to anti-CTLA4 antibody. Immune-profiling showed that CT-26 tumor tissue was infiltrated with more immune cells than Colon 26. Genomic/transcriptomic analyses highlighted thatWnt pathway was one of the potential differences between CT-26 and Colon 26, showing Wnt activity was higher in Colon 26 than CT-26. .

CONCLUSIONS

CT-26 and Colon 26 syngeneic tumor models showed different sensitivity to anti-PD-1 therapy, although both tumor cells are murine colorectal carcinoma cell lines from BALB/c strain. By characterizing the mouse cells lines and tumor-immune context in the tumor tissues with comprehensive analysis approaches, we found that CT-26 showed "hot tumor" profile with more infiltrated immune cells than Colon 26. Further pathway analyses enable us to propose a hypothesis that Wnt pathway could be one of the major factors to differentiate CT-26 from Colon 26 model and link to anti-PD-1 response. Our approach to focus on preclinical tumor models with similar genetic background but different sensitivity to anti-PD-1 therapy would contribute to illustrating the potential mechanism of anti-PD-1 response and to generating a novel concept to synergize current anti-PD-1 therapies for cancer patients.

Advancing to the era of cancer immunotherapy

Cancer greatly affects the quality of life of humans worldwide and the number of patients suffering from it is continuously increasing. Over the last century, numerous treatments have been developed to improve the survival of cancer patients but substantial progress still needs to be made before cancer can be truly cured. In recent years, antitumor immunity has become the most debated topic in cancer research and the booming development of immunotherapy has led to a new epoch in cancer therapy. In this review, we describe the relationships between tumors and the immune system, and the rise of immunotherapy. Then, we summarize the characteristics of tumor‐associated immunity and immunotherapeutic strategies with various molecular mechanisms by showing the typical immune molecules whose antibodies are broadly used in the clinic and those that are still under investigation. We also discuss important elements from individual cells to the whole human body, including cellular mutations and modulation, metabolic reprogramming, the microbiome, and the immune contexture. In addition, we also present new observations and technical advancements of both diagnostic and therapeutic methods aimed at cancer immunotherapy. Lastly, we discuss the controversies and challenges that negatively impact patient outcomes.

Shaping Immune Responses in the Tumor Microenvironment of Ovarian Cancer

Reciprocal signaling between immune cells and ovarian cancer cells in the tumor microenvironment can alter immune responses and regulate disease progression. These signaling events are regulated by multiple factors, including genetic and epigenetic alterations in both the ovarian cancer cells and immune cells, as well as cytokine pathways. Multiple immune cell types are recruited to the ovarian cancer tumor microenvironment, and new insights about the complexity of their interactions have emerged in recent years. The growing understanding of immune cell function in the ovarian cancer tumor microenvironment has important implications for biomarker discovery and therapeutic development. This review aims to describe the factors that shape the phenotypes of immune cells in the tumor microenvironment of ovarian cancer and how these changes impact disease progression and therapy.

Current status of cancer immunotherapy for gynecologic malignancies

Recent cancer immunotherapy development with immune checkpoint inhibitors has shown durable clinical responses in a wide variety of tumor types. These drugs targeting programmed cell death 1, its ligand programmed death ligand 1 and cytotoxic T cell lymphocyte-associated antigen 4 have revolutionized the field of cancer treatment. It is of significant interest in optimizing the immunotherapy for cancer patients beyond the conventional treatments such as surgery, chemotherapy and radiation. Many clinical trials evaluating the safety and efficacy of various combined regimens with immune checkpoint inhibitors have been reported and are in progress. Among gynecologic malignancy, endometrial cancers have distinct subtypes with microsatellite instability-high status and polymerase ɛ mutation. These types have been shown to immunogenic tumors and appropriated candidate for immune checkpoint inhibitors. Also, recurrent cervical cancer showed a promising objective response with single anti-PD1 Ab treatment. Despite their definite outcome and considerable potential of immunotherapy, not all patients received a survival benefit and further understanding of human tumor immunology is essential to improve this type of therapy. In this review, we have summarized the updated results of clinical trials of cancer immunotherapy for gynecologic malignancies and discussed the future perspectives.

Hypoxia and the phenomenon of immune exclusion

Over the last few years, cancer immunotherapy experienced tremendous developments and it is nowadays considered a promising strategy against many types of cancer. However, the exclusion of lymphocytes from the tumor nest is a common phenomenon that limits the efficiency of immunotherapy in solid tumors. Despite several mechanisms proposed during the years to explain the immune excluded phenotype, at present, there is no integrated understanding about the role played by different models of immune exclusion in human cancers. Hypoxia is a hallmark of most solid tumors and, being a multifaceted and complex condition, shapes in a unique way the tumor microenvironment, affecting gene transcription and chromatin remodeling. In this review, we speculate about an upstream role for hypoxia as a common biological determinant of immune exclusion in solid tumors. We also discuss the current state of ex vivo and in vivo imaging of hypoxic determinants in relation to T cell distribution that could mechanisms of immune exclusion and discover functional-morphological tumor features that could support clinical monitoring.

CRISPR Screening of CAR T Cells and Cancer Stem Cells Reveals Critical Dependencies for Cell-Based Therapies

Glioblastoma (GBM) contains self-renewing GBM stem cells (GSC) potentially amenable to immunologic targeting, but chimeric antigen receptor (CAR) T-cell therapy has demonstrated limited clinical responses in GBM. Here, we interrogated molecular determinants of CAR-mediated GBM killing through whole-genome CRISPR screens in both CAR T cells and patient-derived GSCs. Screening of CAR T cells identified dependencies for effector functions, including TLE4 and IKZF2. Targeted knockout of these genes enhanced CAR antitumor efficacy. Bulk and single-cell RNA sequencing of edited CAR T cells revealed transcriptional profiles of superior effector function and inhibited exhaustion responses. Reciprocal screening of GSCs identified genes essential for susceptibility to CAR-mediated killing, including RELA and NPLOC4, the knockout of which altered tumor-immune signaling and increased responsiveness of CAR therapy. Overall, CRISPR screening of CAR T cells and GSCs discovered avenues for enhancing CAR therapeutic efficacy against GBM, with the potential to be extended to other solid tumors. SIGNIFICANCE: Reciprocal CRISPR screening identified genes in both CAR T cells and tumor cells regulating the potency of CAR T-cell cytotoxicity, informing molecular targeting strategies to potentiate CAR T-cell antitumor efficacy and elucidate genetic modifications of tumor cells in combination with CAR T cells to advance immuno-oncotherapy.This article is highlighted in the In This Issue feature, p. 995.

NF-кB inhibition by DHMEQ: in vitro antiproliferative effects on pilocytic astrocytoma and concise review of the current literature

INTRODUCTION

Pilocytic astrocytoma (PA) is the most common brain tumor that affects the pediatric population. Even though PA is benign and treatment only involves surgery, recurrent or unresectable tumors require chemo- and radiotherapy. Besides BRAF, CDKN2A, or IDH mutations, the hyperactivation of the nuclear factor NF-κB contributes to tumor growth and survival.

METHODS

In the present study, we used publicly available data for the in silico analysis of NF-κB subunits (RELA, RELB, REL, NF-κB1, and NF-κB2) expression in PA samples. Besides, in vitro assays were performed to evaluate proliferation, migration, cell death, on the PA cell line Res286 comparing to human primary astrocytes. Sensitization to radiation therapy and temozolomide (TMZ) was also assayed.

RESULTS

Our results showed that all the members of the NF-kB family are upregulated in PA datasets compared to normal brain tissues. Moreover, DHMEQ treatment significantly reduced cell growth and motility, while sensitized cells to ionizing radiation and TMZ, as previously seen in high-grade gliomas.

CONCLUSIONS

This drug presents a potential application in clinical practice for the treatment of recurrent or inoperable PA. Moreover, its use might assist adjuvant chemotherapy and reduce irradiation doses to avoid toxicity to the surrounding tissues.

Enhanced anti-tumor effects of the PD-1 blockade combined with a highly absorptive form of curcumin targeting STAT3

PD‐1/PD‐L1 immune checkpoint inhibitors are promising cancer immunotherapies however responses are still limited and the development of more effective combination immunotherapy is needed. We previously reported that STAT3 activation in cancer cells and immune cells was involved in immune‐resistant mechanisms. In this study, we evaluated the effect of highly absorptive forms of curcumin extracts and synthetic curcumin on anti‐tumor T cell responses. The curcumin po administration resulted in the significant augmentation of in vivo induction of tumor antigen‐specific T cells through restoration of dendritic cells (DCs) by inhibiting directly STAT3 in DCs and indirectly via reduced IL‐6 production from STAT3 activated cancer cells in 2 syngeneic MC38 and CT26 murine tumor models. Curcumin also showed direct DC enhancing activity and enhanced T cell induction for the immunized antigens in non‐tumor‐bearing mice and human hosts. Curcumin restored DC functions in xenogeneic nude mouse model implanted with high IL‐6‐producing human clear cell ovarian cancer cells. The combination of curcumin and PD‐1/PD‐L1 Abs demonstrated a synergistic anti‐tumor activity in MC38 murine tumor models. These results indicated that curcumin augments the induction of tumor antigen‐specific T cells by restoring the T cell stimulatory activity of DCs targeting activated STAT3 in both cancer cells and immune cells. Combination immunotherapy with curcumin and PD‐1/PD‐L1 Ab is an attractive strategy in the development of effective immunotherapy against various cancers.

Anticancer Activity of Novel NF-kappa B Inhibitor DHMEQ by Intraperitoneal Administration

There have been great advances in the therapy of cancer and leukemia. However, there are still many neoplastic diseases that are difficult to treat. For example, it is often difficult to find effective therapies for aggressive cancer and leukemia. An NF-κB inhibitor named dehydroxymethylepoxyquinomicin (DHMEQ) was discovered in 2000. This compound was designed based on the structure of epoxyquinomicin isolated from a microorganism. It was shown to be a specific inhibitor that directly binds to and inactivates NF-κB components. Until now, DHMEQ has been used by many scientists in the world to suppress animal models of cancer and inflammation. Especially, it was shown to suppress difficult cancer models, such as hormone-insensitive breast cancer and prostate cancer, cholangiocarcinoma, and multiple myeloma. No toxicity has been reported so far. DHMEQ was administered via the intraperitoneal (IP) route in most of the animal experiments because of its simplicity. In the course of developmental studies, it was found that IP administration never increased the blood concentration of DHMEQ because of the instability of DHMEQ in the blood. It is suggested that inflammatory cells in the peritoneal cavity would be important for cancer progression, and that IP administration, itself, is important for the effectiveness and safety of DHMEQ. In the present review, we describe mechanism of action, its in vivo anticancer activity, and future clinical use of DHMEQ IP therapy.

IMMUNEPOTENT CRP plus doxorubicin/cyclophosphamide chemotherapy remodel the tumor microenvironment in an air pouch triple-negative breast cancer murine model

In 1889, Steven Paget postulated the theory that cancer cells require a permissive environment to grow. This permissive environment is known as the tumor microenvironment (TME) and nowadays it is evident that the TME is involved in the progression and response to therapy of solid cancer tumors. Triple-negative breast cancer is one of the most lethal types of cancer for women worldwide and chemotherapy remains the standard treatment for these patients. IMMUNEPOTENT CRP is a bovine dialyzable leukocyte extract with immunomodulatory and antitumor properties. The combination of chemotherapy and IMMUNEPOTENT CRP improves clinical parameters of breast cancer patients. In the current study, we aimed to evaluate the antitumor effect of doxorubicin/cyclophosphamide chemotherapy plus IMMUNEPOTENT CRP and its impact over the tumor microenvironment in a triple-negative breast cancer murine model. We evaluated CD8⁺, CD4⁺, T regulatory cells, memory T cells, myeloid-derived suppressor cells, CD71⁺, innate effector cells and molecules such as α-SMA, VEGF, CTLA-4, PD-L1, Gal-3, IDO, IL-2, IFN-γ, IL-12, IL-6, MCP-1, and IL-10 as part of the components of the TME. Doxorubicin/cyclophosphamide + IMMUNEPOTENT CRP decreased tumor volume, prolonged survival, increased infiltrating and systemic CD8⁺ T cells and decreased tumor suppressor molecules (such as PD-L1, Gal-3, and IL-10 among others). In conclusion, we suggest that IMMUNEPOTENT CRP act as a modifier of the TME and the immune response, potentiating or prolonging anti-tumor effects of doxorubicin/cyclophosphamide in a triple-negative breast cancer murine model.

Tumor-intrinsic signaling pathways: key roles in the regulation of the immunosuppressive tumor microenvironment

Immunotherapy is a currently popular treatment strategy for cancer patients. Although recent developments in cancer immunotherapy have had significant clinical impact, only a subset of patients exhibits clinical response. Therefore, understanding the molecular mechanisms of immunotherapy resistance is necessary. The mechanisms of immune escape appear to consist of two distinct tumor characteristics: a decrease in effective immunocyte infiltration and function and the accumulation of immunosuppressive cells in the tumor microenvironment. Several host-derived factors may also contribute to immune escape. Moreover, inter-patient heterogeneity predominantly results from differences in somatic mutations between cancers, which has led to the hypothesis that differential activation of specific tumor-intrinsic pathways may explain the phenomenon of immune exclusion in a subset of cancers. Increasing evidence has also shown that tumor-intrinsic signaling plays a key role in regulating the immunosuppressive tumor microenvironment and tumor immune escape. Therefore, understanding the mechanisms underlying immune avoidance mediated by tumor-intrinsic signaling may help identify new therapeutic targets for expanding the efficacy of cancer immunotherapies.

Approaches to treat immune hot, altered and cold tumours with combination immunotherapies

Immunotherapies are the most rapidly growing drug class and have a major impact in oncology and on human health. It is increasingly clear that the effectiveness of immunomodulatory strategies depends on the presence of a baseline immune response and on unleashing of pre-existing immunity. Therefore, a general consensus emerged on the central part played by effector T cells in the antitumour responses. Recent technological, analytical and mechanistic advances in immunology have enabled the identification of patients who are more likely to respond to immunotherapy. In this Review, we focus on defining hot, altered and cold tumours, the complexity of the tumour microenvironment, the Immunoscore and immune contexture of tumours, and we describe approaches to treat such tumours with combination immunotherapies, including checkpoint inhibitors. In the upcoming era of combination immunotherapy, it is becoming critical to understand the mechanisms responsible for hot, altered or cold immune tumours in order to boost a weak antitumour immunity. The impact of combination therapy on the immune response to convert an immune cold into a hot tumour will be discussed.

Role of nuclear factor-kappa B in feline injection site sarcoma

Background

Chronic inflammation has been implicated in sarcomagenesis. Among various factors, activation of nuclear factor-kappa B (NF-κB) signaling pathway has been documented being able to target genes associated with tumor progression and up-regulate the expression of tumor-promoting cytokines and survival genes in several human solid tumors. Feline injection sites sarcomas (FISS) are malignant entities derived from the mesenchymal origin. The disease has been considered to be associated with vaccine adjuvant, aluminum, which serves as a stimulus continuously inducing overzealous inflammatory and immunologic reactions. To understand the contribution of NF-κB in FISS, detection of activated NF-κB in paraffin-embedded specimens, in vitro establishment of primary cells derived from FISS, and evaluation of the effects of the NF-κB inhibitor, dehydroxymethylepoxyquinomicin (DHMEQ), on primary tumor cells were conducted.

Results

In this study, nuclear expression of NF-κB p65 was detected in 83.3% of FISS cases and not correlated with tumor grading, sex, and age. Primary cells derived from FISS in three cats exhibiting same immunohistochemical characteristics as their original tumor were successfully established. The NF-κB inhibitor, DHMEQ, was able to prevent nuclear translocation of NF-κB p65, inhibit cell proliferation, migration, and colonization in dosage-dependent manners, and induce cell apoptosis in these primary FISS cells.

Conclusions

High expression rate of nuclear NF-κB p65 in FISS cases and dose-dependent inhibitory effects on the growth of FISS primary cells treated with NF-κB inhibitor suggested that NF-κB might be a potential molecular therapeutic target for FISS.

NF-κB Signaling in Ovarian Cancer

The NF-κB signaling pathway is a master and commander in ovarian cancer (OC) that promotes chemoresistance, cancer stem cell maintenance, metastasis and immune evasion. Many signaling pathways are dysregulated in OC and can activate NF-κB signaling through canonical or non-canonical pathways which have both overlapping and distinct roles in tumor progression. The activation of canonical NF-κB signaling has been well established for anti-apoptotic and immunomodulatory functions in response to the tumor microenvironment and the non-canonical pathway in cancer stem cell maintenance and tumor re-initiation. NF-κB activity in OC cells helps to create an immune-evasive environment and to attract infiltrating immune cells with tumor-promoting phenotypes, which in turn, drive constitutive NF-κB activation in OC cells to promote cell survival and metastasis. For these reasons, NF-κB is an attractive target in OC, but current strategies are limited and broad inhibition of this major signaling pathway in normal physiological and immunological functions may produce unwanted side effects. There are some promising pre-clinical outcomes from developing research to target and inhibit NF-κB only in the tumor-reinitiating cancer cell population of OC and concurrently activate canonical NF-κB signaling in immune cells to promote anti-tumor immunity.

Targeting NF-κB-mediated inflammatory pathways in cisplatin-resistant NSCLC

OBJECTIVES

The majority of patients with non-small cell lung cancer (NSCLC) present with advanced stage disease, at which time chemotherapy is usually the most common treatment option. While somewhat effective, patients treated with platinum-based regimens will eventually develop resistance, with others presenting with intrinsic resistance. Multiple pathways have been implicated in chemo-resistance, however the critical underlying mechanisms have yet to be elucidated. The aim of this project was to determine the role of inflammatory mediators in cisplatin-resistance in NSCLC.

MATERIALS AND METHODS

Inflammatory mediator, NF-κB, and its associated pathways were investigated in an isogenic model of cisplatin-resistant NSCLC using age-matched parental (PT) and corresponding cisplatin-resistant (CisR) sublines. Pathways were assessed using mass spectrometry, western blot analysis and qRT-PCR. The cisplatin sensitizing potential of an NF-κB small molecule inhibitor, DHMEQ, was also assessed by means of viability assays and western blot analysis.

RESULTS

Proteomic analysis identified dysregulated NF-κB responsive targets in CisR cells when compared to PT cells, with increased NF-κB expression identified in four out of the five NSCLC sub-types examined (CisR versus PT). DHMEQ treatment resulted in reduced NF-κB expression in the presence of cisplatin, and re-sensitized CisR cells to the cytotoxic effects of the drug.

CONCLUSION

This study identified NF-ĸB as a potential therapeutic target in cisplatin-resistant NSCLC. Furthermore, inhibition of NF-ĸB using DHMEQ re-sensitized chemo-resistant cells to cisplatin treatment.

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.

Clinical Relevance and Immunosuppressive Pattern of Circulating and Infiltrating Subsets of Myeloid-Derived Suppressor Cells (MDSCs) in Epithelial Ovarian Cancer

Myeloid-derived suppressor cells (MDSCs) expansion is a hallmark of cancer. Three major MDSC subsets defined as monocytic (M)-MDSCs, polymorphonuclear (PMN)-MDSCs and early stage (e)MDSCs can be revealed in human diseases. However, the clinical relevance and immunosupressive pattern of these cells in epithelial ovarian cancer (EOC) are unknown. Therefore, we performed a comprehensive analysis of each MDSC subset and immunosupressive factors in the peripheral blood (PB), peritoneal fluid (PF), and the tumor tissue (TT) samples from EOC and integrated this data with the patients' clinicopathological characteristic. MDSCs were analyzed using multicolor flow cytometry. Immunosuppressive factors analysis was performed with ELISA and qRT-PCR. The level of M-MDSCs in the PB/PF/TT of EOC was significantly higher than in healthy donors (HD); frequency of PMN-MDSCs was significantly greater in the TT than in the PB/PF and HD; while the level of eMDSCs was greater in the PB compared with the PF and HD. Elevated abundance of tumor-infiltrating M-MDSCs was associated with advanced stage and high grade of EOC. An analysis of immunosuppressive pattern showed significantly increased blood-circulating ARG/IDO/IL-10-expressing M- and PMN-MDSCs in the EOC patients compared with HD and differences in the accumulation of these subsets in the three tumor immune microenvironments (TIME). This accumulation was positively correlated with levels of TGF-β and ARG1 in the plasma and PF. Low level of blood-circulating and tumor-infiltrating M-MDSCs, but neither PMN-MDSCs nor eMDSCs was strongly associated with prolonged survival in ovarian cancer patients. Our results highlight M-MDSCs as the subset with potential the highest clinical significance.

lncRNA UCA1-Mediated Cdc42 Signaling Promotes Oncolytic Vaccinia Virus Cell-to-Cell Spread in Ovarian Cancer

Oncolytic vaccinia virus (OVV) has demonstrated appropriate safety profiles for clinical development. Although designed to kill cancer cells efficiently, OVV sensitivity varies in individual cancers, and predictive biomarkers of therapeutic responses have not been identified. Here we found that OVV was much more efficient in KFTX paclitaxel-resistant ovarian cancer cells compared to that in KFlow paclitaxel-sensitive cells. Microarray analysis identified long non-coding RNA urothelial carcinoma-associated 1 (UCA1) upregulation, which contributed to both enhanced paclitaxel resistance and OVV spread. In addition, UCA1 expression correlated with efficient OVV spread in other ovarian cell lines and primary cancer cell cultures. When host pathways underlying OVV spread were analyzed, differences were detected in the activation of the Rho GTPase Cdc42, suggesting that filopodia formation enhances OVV cell-to-cell spread and tumor migration. Moreover, we established a clinically relevant mouse model of peritoneal metastasis using KFTX or KFlow cells. Paclitaxel exerted anti-tumor effects on KFlow, but not KFTX, tumors. In mice bearing KFTX cells after paclitaxel failure, OVV treatment induced the regression of residual tumors and improved survival. Our findings demonstrated that UCA1 promotes OVV cell-to-cell spread in ovarian cancer, resulting in enhanced therapeutic outcome.

Comparison of anti-atopic dermatitis activities between DHMEQ and tacrolimus ointments in mouse model without stratum corneum

This study is aimed to further investigate the anti-atopic dermatitis (AD) activities of dehydroxymethylepoxyquinomicin (DHMEQ) ointment and compare its effect with that of tacrolimus ointment based on the previous study that DHMEQ improves AD-like lesions. AD were induced by 2,4-dinitroclilorobenzene/oxazolone (DNCB/OX) repeatedly on the ears of BABL/C mice while medical tape was additionally used to disrupt stratum corneum in order to exacerbate the lesions. The mice were randomly divided into groups, which are normal, vehicle, DHMEQ (0.1%) and tacrolimus (0.1%). Those in the last two groups were externally applied with DHMEQ ointment and tacrolimus ointment, respectively. The results showed that both of them significantly improved dermatitis symptoms of DNCB/OX-induced AD-like lesions, such as redness, itching, weeping, scaling and thickening of the skin, while reducing epidermis thickness, dermis thickness and the number of mast cells as well, which were examined histopathologically. In contrast with DHMEQ, tacrolimus led to a significant decrease in body weight after long-term application. Both DHMEQ and tacrolimus suppress DNCB-induced increase of serum total IgE and attenuate expression of inflammatory factors IL-4, IL-6, IL-13, IL-1β and interferon (IFN)-γ in the disrupted ear tissues. On the other hand, the mice applied with tacrolimus became obviously irritable, jumping up and down, and inflammatory exudation on the lesioned-skin surface of the mice was remarkably observed. Contrary to the side effects made by tacrolimus, DHMEQ didn't cause any adverse stimulus response. As a conclusion, DHMEQ is safer, milder and more suitable for long-term use than tacrolimus for the treatment of AD-like lesions.

Prognostic value of serum IL-8 and IL-10 in patients with ovarian cancer undergoing chemotherapy

Prognostic value of serum interleukin-8 (IL-8) and interleukin-10 (IL-10) in patients with ovarian cancer undergoing chemotherapy was evaluated. The clinical data of ovarian tumor patients in Yidu Central Hospital of Weifang treated from January 2012 to December 2014 was retrospectively analyzed, 92 cases of which were malignant group, 64 cases were benign group, and 58 healthy subjects were selected as control group. Serum expression levels of IL-8 and IL-10 of the three groups were detected by enzyme-linked immunosorbent assay. Serum expression levels of IL-8 and IL-10 in benign and malignant groups both were higher than those in healthy control group (P<0.001). Serum expression levels of IL-8 and IL-10 of patients with ovarian cancer at III+IV stage were higher than that at I+II stage (P<0.001). Serum expression levels of IL-8 and IL-10 of patients with malignant ovarian tumors before chemotherapy were higher than those after chemotherapy (P<0.001). Serum levels of IL-8 and IL-10 of patients with malignant ovarian tumors in stable condition after chemotherapy were lower than those with recurrence and metastasis after chemotherapy (P<0.001). The median of serum expression levels of IL-8 and IL-10 was divided into low expression group and high expression group. The survival time of patients in high serum IL-8 and IL-10 expression group was significantly shorter than that in serum IL-8 and IL-10 low expression group (P<0.05). The survival time was negatively correlated with the expression levels of IL-8 and IL-10. Serum expression levels of IL-8 and IL-10 are closely related to the stages and prognosis of ovarian cancer. IL-8 and IL-10 may be involved in the occurrence and development of ovarian cancer. There are certain reference values on the changes of IL-8 and IL-10 levels, which may reflect the biological behavior and prognosis of ovarian cancer.

Genomics to immunotherapy of ovarian clear cell carcinoma: Unique opportunities for management

Ovarian clear cell carcinoma (OCCC) is distinctive from other histological types of epithelial ovarian cancer, with genetic/epigenetic alterations, a specific immune-related molecular profile, and epidemiologic associations with ethnicity and endometriosis. These findings allow for the exploration of unique and specific treatments for OCCC. Two major mutated genes in OCCC are PIK3CA and ARID1A, which are frequently coexistent with each other. Other genes' alterations also contribute to activation of the PI3K (e.g. PIK3R1 and PTEN) and dysregulation of the chromatin remodeling complex (e.g. ARID1B, and SMARKA4). Although the number of focal copy number variations is small in OCCC, amplification is recurrently detected at chromosome 20q13.2 (including ZNF217), 8q, and 17q. Both expression and methylation profiling highlight the significance of adjustments to oxidative stress and inflammation. In particular, up-regulation of HNF-1β resulting from hypomethylation contributes to the switch from anaerobic to aerobic glucose metabolism. Additionally, up-regulation of HNF-1β activates STAT3 and NF-κB signaling, and leads to immune suppression via production of IL-6 and IL-8. Immune suppression may also be induced by the increased expression of PD-1, Tim-3 and LAG3. Mismatch repair deficient (microsatellite instable) tumors as found in Lynch syndrome also induce immune suppression in some OCCC. In a recent phase II clinical trial in heavily-treated platinum-resistant ovarian cancer, two out of twenty cases with a complete response to the anti-PD-1 antibody, nivolumab, were OCCC subtypes. Thus, the immune-suppressive state resulting from both genetic alterations and the unique tumor microenvironment may be associated with sensitivity to immune checkpoint inhibitors in OCCC. In this review, we highlight recent update and progress in OCCC from both the genomic and immunologic points of view, addressing the future candidate therapeutic options.

Ovarian Cancer Immunotherapy: Preclinical Models and Emerging Therapeutics

Immunotherapy has emerged as one of the most promising approaches for ovarian cancer treatment. The tumor microenvironment (TME) is a key factor to consider when stimulating antitumoral responses as it consists largely of tumor promoting immunosuppressive cell types that attenuate antitumor immunity. As our understanding of the determinants of the TME composition grows, we have begun to appreciate the need to address both inter- and intra-tumor heterogeneity, mutation/neoantigen burden, immune landscape, and stromal cell contributions. The majority of immunotherapy studies in ovarian cancer have been performed using the well-characterized murine ID8 ovarian carcinoma model. Numerous other animal models of ovarian cancer exist, but have been underutilized because of their narrow initial characterizations in this context. Here, we describe animal models that may be untapped resources for the immunotherapy field because of their shared genomic alterations and histopathology with human ovarian cancer. We also shed light on the strengths and limitations of these models, and the knowledge gaps that need to be addressed to enhance the utility of preclinical models for testing novel immunotherapeutic approaches.

Lycopene Protects Against Spontaneous Ovarian Cancer Formation in Laying Hens

Background

Dietary intake of lycopene has been associated with a reduced risk of ovarian cancer, suggesting its chemopreventive potential against ovarian carcinogenesis. Lycopene's molecular mechanisms of action in ovarian cancer have not been fully understood. Therefore, in the present study, we investigated the effects of lycopene on the ovarian cancer formation using the laying hen model, a biologically relevant animal model of spontaneous ovarian carcinogenesis due to high incidence rates similar to humans.

Methods

In this study, a total of 150 laying hens at age of 102 weeks were randomized into groups of 50: a control group (0 mg of lycopene per kg of diet) and two treatment groups (200 mg or 400 mg of lycopene per kg of diet, or ~26 and 52 mg/d/hen, respectively). At the end of 12 months, blood, ovarian tissues and tumors were collected.

Results

We observed that lycopene supplementation significantly reduced the overall ovarian tumor incidence (P < 0.01) as well as the number and the size of the tumors (P < 0.004 and P < 0.005, respectively). Lycopene also significantly decreased the rate of adenocarcinoma, including serous and mucinous subtypes (P < 0.006). Moreover, we also found that the serum level of oxidative stress marker malondialdehyde was significantly lower in lycopene-fed hens compared to control birds (P < 0.001). Molecular analysis of the ovarian tumors revealed that lycopene reduced the expression of NF-κB while increasing the expression of nuclear factor erythroid 2 and its major target protein, heme oxygenase 1. In addition, lycopene supplementation decreased the expression of STAT3 by inducing the protein inhibitor of activated STAT3 expression in the ovarian tissues.

Conclusions

Taken together, our findings strongly support the potential of lycopene in the chemoprevention of ovarian cancer through antioxidant and anti-inflammatory mechanisms.

Inhibition of Late and Early Phases of Cancer Metastasis by the NF-κB Inhibitor DHMEQ Derived from Microbial Bioactive Metabolite Epoxyquinomicin: A Review

We previously designed and synthesized dehydroxyepoxyquinomicin (DHMEQ) as an inhibitor of NF-κB based on the structure of microbial secondary metabolite epoxyquinomicin C. DHMEQ showed anti-inflammatory and anticancer activity in various in vivo disease models without toxicity. On the other hand, the process of cancer metastasis consists of cell detachment from the primary tumor, invasion, transportation by blood or lymphatic vessels, invasion, attachment, and formation of secondary tumor. Cell detachment from the primary tumor and subsequent invasion are considered to be early phases of metastasis, while tumor cell attachment to the tissue and secondary tumor formation the late phases. The assay system for the latter phase was set up with intra-portal-vein injection of pancreatic cancer cells. Intraperitoneal administration of DHMEQ was found to inhibit liver metastasis possibly by decreasing the expression of MMP-9 and IL-8. Also, when the pancreatic cancer cells treated with DHMEQ were inoculated into the peritoneal cavity of mice, the metastatic foci formation was inhibited. These results indicate that DHMEQ is likely to inhibit the late phase of metastasis. Meanwhile, we have recently employed three-dimensional (3D) culture of breast cancer cells for the model of early phase metastasis, since the 3D invasion just includes cell detachment and invasion into the matrix. DHMEQ inhibited the 3D invasion of breast cancer cells at 3D-nontoxic concentrations. In this way, DHMEQ was shown to inhibit the late and early phases of metastasis. Thus, DHMEQ is likely to be useful for the suppression of cancer metastasis.

Rediscovery of NF-κB signaling in nasopharyngeal carcinoma: How genetic defects of NF-κB pathway interplay with EBV in driving oncogenesis?

Nasopharyngeal carcinoma (NPC) is a unique EBV-associated subtype of head and neck cancer, which has the highest incidence in Southern China and eastern South Asia. The interaction between genetic risk factors and environmental challenge, have been considered to contribute to the development of nasopharyngeal carcinogenesis. Constitutive activation of NF-κB signaling has been seen in NPC tissues and is associated with unfavorable prognosis. Recently, several whole exome sequencing study consistently revealed that high frequency mutations of NF-κB pathway negative regulators is common in nasopharyngeal carcinoma, which reinforce the importance of NF-κB driving oncogenesis. This review focuses on the current state of research in role of NF-κB in NPC carcinogenesis. We summarized the newly identified loss of function (LOF) mutations on NF-κB negative regulators leading to it's activation bypass LMP-1 stimulation. We discussed the critical role of NF-κB activation in immortalization and transformation of nasopharygeal epithelium. We also depicted how NF-κB signaling mediated chronic inflammation contribute to persistent EBV infection, immune evasion of EBV infected cells, metabolic reprogramming, and cancer stem cells (CSCs) formation in NPC. Lastly, we discussed the clinical resonance of targeting NF-κB for NPC precise therapy.

Involvement of local renin-angiotensin system in immunosuppression of tumor microenvironment

To improve current cancer immunotherapies, strategies to modulate various immunosuppressive cells including myeloid derived suppressor cells (MDSC) which were shown to be negative factors in immune‐checkpoint blockade therapy, need to be developed. In the present study, we evaluated the role of the local renin‐angiotensin system (RAS) in the tumor immune‐microenvironment using murine models bearing tumor cell lines in which RAS was not involved in their proliferation and angiogenetic ability. Giving angiotensin II receptor blockers (ARB) to C57BL/6 mice bearing murine colon cancer cell line MC38 resulted in significant enhancement of tumor antigen gp70 specific T cells. ARB administration did not change the numbers of CD11b⁺ myeloid cells in tumors, but significantly reduced their T‐cell inhibitory ability along with decreased production of various immunosuppressive factors including interleukin (IL)‐6, IL‐10, vascular endothelial growth factor (VEGF), and arginase by CD11b⁺ cells in tumors. ARB also decreased expression of immunosuppressive factors such as chemokine ligand 12 and nitric oxide synthase 2 in cancer‐associated fibroblasts (CAF). Last, combination of ARB and anti‐programmed death‐ligand 1 (PD‐L1) antibodies resulted in significant augmentation of anti‐tumor effects in a CD8⁺ T cell‐dependent way. These results showed that RAS is involved in the generation of an immunosuppressive tumor microenvironment caused by myeloid cells and fibroblasts, other than the previously shown proliferative and angiogenetic properties of cancer cells and macrophages, and that ARB can transform the immunosuppressive properties of MDSC and CAF and could be used in combination with PD‐1/PD‐L1 immune‐checkpoint blockade therapy.

Molecular mechanisms of anticancer effects of Glucosamine

Glucosamine is an amino sugar that is produced naturally in human body. It is an essential carbohydrate component of many cellular glycoproteins, glycolipids, and glycosaminoglycans (GAGs). This popular over-the-counter supplement is also found in the exoskeleton of crustaceans. Glucosamine and its derivatives have a long history in medicine for inflammatory conditions specially to relieve arthritis. This dietary supplement has numerous biological and pharmacological properties, including anti-inflammatory, antioxidant, anti-aging, anti-fibrotic, neuroprotective and cardioprotective activities. Many studies have shown that glucosamine has anti-cancer activity through influence on biological pathways involved in cell death, apoptosis, cell proliferation, and angiogenesis. Accordingly, this comprehensive review summarizes anti-cancer molecular mechanisms of glucosamine in details.

Unlocking the NF-κB Conundrum: Embracing Complexity to Achieve Specificity

Transcription factors of the nuclear factor κB (NF-κB) family are central coordinating regulators of the host defence responses to stress, injury and infection. Aberrant NF-κB activation also contributes to the pathogenesis of some of the most common current threats to global human health, including chronic inflammatory diseases, autoimmune disorders, diabetes, vascular diseases and the majority of cancers. Accordingly, the NF-κB pathway is widely considered an attractive therapeutic target in a broad range of malignant and non-malignant diseases. Yet, despite the aggressive efforts by the pharmaceutical industry to develop a specific NF-κB inhibitor, none has been clinically approved, due to the dose-limiting toxicities associated with the global suppression of NF-κB. In this review, we summarise the main strategies historically adopted to therapeutically target the NF-κB pathway with an emphasis on oncology, and some of the emerging strategies and newer agents being developed to pharmacologically inhibit this pathway.

Tumor-derived factors affecting immune cells

Tumor progression is accompanied by the production of a wide array of immunosuppressive factors by tumor and non-tumor cells forming the tumor microenvironment. These factors belonging to cytokines, growth factors, metabolites, glycan-binding proteins and glycoproteins are responsible for the establishment of immunosuppressive networks leading towards tumor promotion, invasion and metastasis. In pre-clinical tumor models, the inactivation of some of these suppressive networks reprograms the phenotypic and functional features of tumor-infiltrating immune cells, ultimately favoring effective anti-tumor immune responses. We will discuss factors and mechanisms identified in both mouse and human tumors, and the possibility to associate drugs inhibiting these mechanisms with new immunotherapy strategies already entered in the clinical practice.

Prediction of therapy response in ovarian cancer: Where are we now?

Therapy resistance is a major challenge in the management of ovarian cancer (OC). Advances in detection and new technology validation have led to the emergence of biomarkers that can predict responses to available therapies. It is important to identify predictive biomarkers to select resistant and sensitive patients in order to reduce important toxicities, to reduce costs and to increase survival. The discovery of predictive and prognostic biomarkers for monitoring therapy is a developing field and provides promising perspectives in the era of personalized medicine. This review article will discuss the biology of OC with a focus on targetable pathways; current therapies; mechanisms of resistance; predictive biomarkers for chemotherapy, antiangiogenic and DNA-targeted therapies, and optimal cytoreductive surgery; and the emergence of liquid biopsy using recent studies from the Medline database and ClinicalTrials.gov.

Novel augmentation by bufalin of protein kinase C-induced cyclooxygenase-2 and IL-8 production in human breast cancer cells

Cyclooxygenase-2 (COX-2) and IL-8 are two inflammatory mediators induced by protein kinase C (PKC) via various stimuli. Both contribute significantly to cancer progression. Bufalin, a major active component of the traditional Chinese medicine Chan Su, is known to induce apoptosis in various cancer cells. This study clarifies the role and mechanism of bufalin action during PKC regulation of COX-2/IL-8 expression and investigates the associated impact on breast cancer. Using MB-231 breast cancer cells, bufalin augments PKC induction of COX-2/IL-8 at both the protein and mRNA levels, and the production of prostaglandin E2 (PGE2) and IL-8. The MAPK and NF-κB pathways are involved in both the PKC-mediated and bufalin-promoted PKC regulation of COX-2/IL-8 production. Bufalin increases PKC-induced MAPKs phosphorylation and NF-κB nuclear translocation. PGE2 stimulates the proliferation/migration of breast cancer cells. Furthermore, PKC-induced matrix metalloproteinase 3 expression is enhanced by bufalin. Bufalin significantly enhances breast cancer xenograft growth, which is accompanied by an elevation in COX-2/IL-8 expression. In conclusion, bufalin seems to promote the inflammatory response in vitro and in vivo, and this occurs, at least in part, by targeting the MAPK and NF-κB pathways, which then enhances the growth of breast cancer cells.

Cancer-induced heterogeneous immunosuppressive tumor microenvironments and their personalized modulation

Although recent cancer immunotherapy strategies, including immune-checkpoint blockade (i.e. blocking PD-1, PD-L1 or CTLA-4), have shown durable clinical effects in some (but not all) patients with various advanced cancers, further understanding of human immunopathology, particularly in tumor microenvironments, is essential to improve this type of therapy. The major hurdle for immunotherapy is the immunosuppression that is found in cancer patients. There are two types of immunosuppression: one is induced by gene alterations in cancer; the other is local adaptive immunosuppression, triggered by tumor-specific T cells in tumors. The former is caused by multiple mechanisms via various immunosuppressive molecules and via cells triggered by gene alterations, including activated oncogenes, in cancer cells. The various immunosuppressive mechanisms involve signaling cascades that vary among cancer types, subsets within cancer types and individual cancers. Therefore, personalized immune-interventions are necessary to appropriately target oncogene-induced signaling that modulates anti-cancer immune responses, on the basis of genetic and immunological analysis of each patient. Further understanding of human cancer immunopathology may lead to real improvement of current cancer immunotherapies.

Tumor-derived factors modulating dendritic cell function

Dendritic cells (DC) play unique and diverse roles in the tumor occurrence, development, progression and response to therapy. First of all, DC can actively uptake tumor-associated antigens, process them and present antigenic peptides to T cells inducing and maintaining tumor-specific T cell responses. DC interaction with different immune effector cells may also support innate antitumor immunity, as well as humoral responses also known to inhibit tumor development in certain cases. On the other hand, DC are recruited to the tumor site by specific tumor-derived and stroma-derived factors, which may also impair DC maturation, differentiation and function, thus resulting in the deficient formation of antitumor immune response or development of DC-mediated tolerance and immune suppression. Identification of DC-stimulating and DC-suppressing/polarizing factors in the tumor environment and the mechanism of DC modulation are important for designing effective DC-based vaccines and for recovery of immunodeficient resident DC responsible for maintenance of clinically relevant antitumor immunity in patients with cancer. DC-targeting tumor-derived factors and their effects on resident and administered DC in the tumor milieu are described and discussed in this review.

Atractylenolide I modulates ovarian cancer cell-mediated immunosuppression by blocking MD-2/TLR4 complex-mediated MyD88/NF-κB signaling in vitro

BACKGROUND

TLR4/MD-2 complex-mediated MyD88-dependent activation of NF-κB and Akt promotes tumor-associated immunosuppression in epithelial ovarian cancer (EOC) via induction of immunesuppressive cytokines and indoleamine 2,3-dioxygenase (IDO). Atractylenolide I (AO-1) is a naturally occurring sesquiterpene lactone known to change the conformational ensemble of human MD-2 on EOC cells. This study examined the modulation by AO-1 of TLR4/MD-2 complex-mediated MyD88/NF-κB signaling.

METHODS

The expression and activation of NF-κB, Akt and IDO1 by MyD88(+) EOC SKOV3 cells was determined using western blot; the TLR4/MD-2 complex on SKOV3 cells and the phenotype of T lymphocytes were determined using flow cytometry; IDO activity was evaluated by measuring L-kynurenine; Immunesuppressive cytokines were detected using ELISA; T-cell proliferation to mitogen stimulation was assessed by MTT assay; the cytotoxicity of lymphocytes and NK cells was measured using LDH-cytotoxicity assay.

RESULTS

AO-1 could down-regulate expression of TLR4/MD-2 complex, resulting in downregulation of MyD88/NF-κB signaling and activation of NF-κB, Akt and IDO1 and secretion of IL-6, TGF-β1, VEGF and IL-17A by EOC SKOV3 cells, and further reduce increased levels of regulatory T cells (Treg cells) and improve decreased proliferative response and antitumor cytotoxicity of T lymphocytes exposed to EOC SKOV3 cell supernatant.

CONCLUSION

AO-1 may reverse EOC cell-mediated immunosuppression through blocking TLR4/MD-2 complex-mediated MyD88/NF-κB signaling.

Targeting the hallmarks of ovarian cancer: The big picture

OBJECTIVE

As a result of relevant achievements in the field of translational research, several active drugs and multiple biological targets are available in ovarian cancer (OC). In this complex scenario, there is an urgent need to effectively summarize the available data in order to update conclusions, and outline perspectives.

METHODS

The results in terms of target identification and drug development have been summarized using the well-known hallmarks of cancer firstly described, and recently modified by Hanahan and Weinberg [1-2]. Published data from clinical trials have been retrieved from PubMed, Embase, CINAHL and Cochrane database. Ongoing clinical trials were searched using clinicaltrials.gov web platform, and identified using NCT number.

RESULTS

Genomic instability and angiogenesis are the most actively investigated hallmarks in high-grade serous OC, and the inhibition of tumor immune evasion appears as the emerging strategy for molecularly-driven therapy. Targeting sustained proliferative signaling through MEK and mTOR inhibitors seems the most promising approach in clear cell, and low-grade serous OC.

CONCLUSIONS

This substantial amount of data suggests that targeted therapies are already part of the clinical and therapeutic management of OC patients. The expectations of getting from translational research a better knowledge of tumor biology and therefore personalized drugs are high and worthy of maximum effort from referral centers.

Immunosuppressive parameters in serum of ovarian cancer patients change during the disease course

Neoplastic cells can escape immune control leading to cancer growth. Regulatory T cells (Treg), myeloid-derived suppressor cells (MDSC) and tumor-associated macrophages (TAM) are crucial in immune escape. TAM are divided based on their immune profile, M1 are immunostimulatory while M2 are immunosuppressive. Research so far has mainly focused on the intratumoral behavior of these cells. This study, on the other hand, explored the systemic changes of the key metabolites [IL-4 (interleukin), IL-13, arginase, IL-10, VEGF-A (vascular endothelial growth factor), CCL-2 (chemokine (C-C) motif ligand 2) and TGF-β (transforming growth factor)] linked to Treg, MDSC and TAM during the course of the disease in ovarian and fallopian tube cancer patients. Serum samples were therefore analyzed at diagnosis, after (interval)-debulking surgery and after chemotherapy (paclitaxel-carboplatin). We also determined galectin-1 (gal-1), involved in angiogenesis and tumor-mediated immune evasion. We found significantly lower levels of IL-10, VEGF-A, TGF-β and arginase and higher levels of gal-1 after chemotherapy compared to diagnosis. After debulking surgery, a decrease in IL-10 was significant. Gal-1 and CCL-2 appeared independent prognostic factors for progression-free and overall survival (OS) (multivariate analysis). These results will help us in the decision making of future therapies in order to further modulate the immune system in a positive way.