Randomized, Double-Blind, Placebo-Controlled Phase III Study of Tasquinimod in Men With Metastatic Castration-Resistant Prostate Cancer

Targeting the tumor microenvironment, a new therapeutic approach for prostate cancer

BACKGROUND

A growing number of studies have shown that in addition to adaptive immune cells such as CD8 + T cells and CD4 + T cells, various other cellular components within prostate cancer (PCa) tumor microenvironment (TME), mainly tumor-associated macrophages (TAMs), cancer-associated fibroblasts (CAFs) and myeloid-derived suppressor cells (MDSCs), have been increasingly recognized as important modulators of tumor progression and promising therapeutic targets.

OBJECTIVE

In this review, we aim to delineate the mechanisms by which TAMs, CAFs and MDSCs interact with PCa cells in the TME, summarize the therapeutic advancements targeting these cells and discuss potential new therapeutic avenues.

METHODS

We searched PubMed for relevant studies published through December 10 2023 on TAMs, CAFs and MDSCs in PCa.

RESULTS

TAMs, CAFs and MDSCs play a critical role in the tumorigenesis, progression, and metastasis of PCa. Moreover, they substantially mediate therapeutic resistance against conventional treatments including anti-androgen therapy, chemotherapy, and immunotherapy. Therapeutic interventions targeting these cellular components have demonstrated promising effects in preclinical models and several clinical trials for PCa, when administrated alone, or combined with other anti-cancer therapies. However, the lack of reliable biomarkers for patient selection and incomplete understanding of the mechanisms underlying the interactions between these cellular components and PCa cells hinder their clinical translation and utility.

CONCLUSION

New therapeutic strategies targeting TAMs, CAFs, and MDSCs in PCa hold promising prospects. Future research endeavors should focus on a more comprehensive exploration of the specific mechanisms by which these cells contribute to PCa, aiming to identify additional drug targets and conduct more clinical trials to validate the safety and efficacy of these treatment strategies.

Systemic treatment options for metastatic castration resistant prostate cancer: A living systematic review

Background

Optimal treatment selection for metastatic castration resistant prostate cancer (mCRPC) remains challenging due to evolving standards of care in castration sensitive setting.

Purpose

To synthesize and appraise evidence on systemic therapy for mCRPC patients stratified by prior therapy and HRR alterations informing a clinical practice guideline.

Data Sources

MEDLINE and EMBASE (inception to 5 March 2025) using living search.

Study Selection

Randomized clinical trials assessing systemic therapy in mCRPC.

Data Extraction

Primary outcomes assessed were progression free survival (PFS) and overall survival (OS).

Data Synthesis

This report of the living systematic review (LSR) includes 143 trials with 17,523 patients (59 phase III/IV trials, 8,941 patients; 84 phase II, 8,582 patients). In the setting of prior androgen deprivation therapy (ADT) alone or ADT+docetaxel, treatment benefit was observed with poly (ADP-ribose) polymerase inhibitors (PARPi) in combination with androgen receptor pathway inhibitors (ARPI) for BRCA+ subgroup. In the setting of prior ADT+ARPI or ADT+ARPI+docetaxel, treatment benefit was observed with PARPi monotherapy for BRCA+ subgroup. Treatment benefit with PARPi may be observed for select non-BRCA homologous recombination repair (HRR) alterations (CDK12, PALB2). Treatment benefit was observed with abiraterone, enzalutamide, cabazitaxel, docetaxel (if no prior docetaxel), and Lu177 (if PSMA+) for patients without HRR alterations.

Limitations

Study-level data and indirectness in evidence.

Conclusion

Findings from the current LSR suggest that optimal treatment for mCRPC should be individualized based on prior therapy and HRR alterations. Current evidence favors PARPi alone (ARPI exposed) or in combination with ARPI (ARPI naïve) for patients with BRCA alterations, while ARPI alone, chemotherapy, and Lu177 remain potential options for patients without HRR alterations.

Targeting immune checkpoints on myeloid cells: current status and future directions

Myeloid cells accumulate extensively in most tumors and play a critical role in immunosuppression of the tumor microenvironment (TME). Like T cells, myeloid cells also express immune checkpoint molecules, which induce the immunosuppressive phenotype of these cells. In this review, we summarize the tumor-promoting function and immune checkpoint expression of four types of myeloid cells: macrophages, neutrophils, dendritic cells, and myeloid-derived suppressor cells, which are the main components of the TME. By summarizing the research status of myeloid checkpoints, we propose that blocking immune checkpoints on myeloid cells might be an effective strategy to reverse the immunosuppressive status of the TME. Moreover, combining nanotechnology, cellular therapy, and bispecific antibodies to achieve precise targeting of myeloid immune checkpoints can help to avoid the adverse effects of systemic administration, ultimately achieving a balance between efficacy and safety in cancer therapy.

Ocular surface squamous neoplasia: Update on genetics, epigenetics and opportunities for targeted therapy

PURPOSE

The purpose of this review is to explore the molecular foundations of ocular surface squamous neoplasia (OSSN), focusing on the genetic and epigenetic aspects. While current management strategies include surgical excision and medical therapies, the understanding of OSSN's molecular basis remains limited, hindering the development of targeted treatments.

METHODS

A comprehensive MEDLINE search was conducted for literature published between January 1993 and October 2023. Only studies with original data on molecular, genetic, or epigenetic mechanisms, such as mutations, gene expression, and genetic predispositions were included. Articles were excluded if they focused solely on clinical management without addressing these factors, or if they were reviews, editorials, or opinion pieces.

RESULTS

The search yielded a total of 108 articles, out of which 39 articles met the criteria for further analysis. Investigations into OSSN have identified key DNA mutations in the TP53, HGF, EGFR, TERT, and CDKN2A genes, indicating common oncogenic pathways shared with other squamous cell carcinomas (SCCs). Significant epigenetic changes were identified, including DNA methylation, histone modifications, and altered miRNA expression patterns. Epigenetic dysregulation of critical tumor suppressors and oncoproteins, further highlight the complex genetic landscape of OSSN.

CONCLUSION

The molecular alterations identified in OSSN not only enhance our understanding of its biology but also have potential as novel biomarkers for early detection, prognostic evaluation, and as therapeutic targets. The identification of genetic and epigenetic markers in OSSN signifies progress towards personalized medicine approaches. Further studies and collaborative efforts are essential to validate these molecular markers and translate them into clinical practice, potentially revolutionizing OSSN management and improving patient outcomes.

MDSC: a new potential breakthrough in CAR-T therapy for solid tumors

Chimeric antigen receptor T (CAR-T) cell therapy has shown remarkable success in hematologic malignancies but has encountered challenges in effectively treating solid tumors. One major obstacle is the presence of the immunosuppressive tumor microenvironment (TME), which is mainly built by myeloid-derived suppressor cells (MDSCs). Recent studies have shown that MDSCs have a detrimental effect on CAR-T cells due to their potent immunosuppressive capabilities. Targeting MDSCs has shown promising results to enhance CAR-T immunotherapy in preclinical solid tumor models. In this review, we first highlight that MDSCs increase tumor proliferation, transition, angiogenesis and encourage circulating tumor cells (CTCs) extravasation leading to tumor progression and metastasis. Moreover, we describe the main characteristics of the immunosuppressive activities of MDSCs on T cells in TME. Most importantly, we summarize targeting therapeutic strategies of MDSCs in CAR-T therapies against solid tumors. These strategies include (1) therapeutic targeting of MDSCs through small molecule inhibitors and large molecule antibodies; (2) CAR-T targeting cancer cell antigen combination with MDSC modulatory agents; (3) cytokine receptor antigen-targeted CAR-T indirectly or directly targeting MDSCs reshapes TME; (4) modified natural killer (NK) cells expressing activating receptor directly targeting MDSCs; and (5) CAR-T directly targeting MDSC selective antigens. In the near future, we are expected to witness the improvement of CAR-T cell therapies for solid tumors by targeting MDSCs in clinical practice.

Inflammatory role of S100A8/A9 in the central nervous system non-neoplastic diseases

S100A8 (MRP8) and S100A9 (MRP14) are critical mediators of the inflammatory response; they are usually present as heterodimers because of the instability of homodimers. Studies have demonstrated that S100A8/A9 expression is significantly upregulated in several central nervous system (CNS) diseases. S100A8/A9 is actively released by neutrophils and monocytes; it plays a key role in regulating the inflammatory response by stimulating leukocyte recruitment and inducing cytokine secretion during inflammation. Additionally, S100A8/A9 can be used as a diagnostic biomarker for several CNS diseases and as a predictor of therapeutic response to inflammation-related diseases. In this work, we reviewed our current understanding of S100A8/A9 overexpression in inflammation and its importance in the development and progression of CNS inflammatory diseases, such as Alzheimer's disease (AD), Parkinson's disease (PD), multiple sclerosis (MS), and stroke, and the functional roles and therapeutic applications of S100A8/A9 in these diseases. Finally, we discussed the current barriers and future research directions of S100A8/A9 in CNS diseases.

Trisomy 8 Defines a Distinct Subtype of Myeloproliferative Neoplasms Driven by the MYC-Alarmin Axis

Despite advances in understanding the genetic abnormalities in myeloproliferative neoplasms (MPN) and the development of JAK2 inhibitors, there is an urgent need to devise new treatment strategies, particularly for patients with triple-negative (TN) myelofibrosis (MF) who lack mutations in the JAK2 kinase pathway and have very poor clinical outcomes. Here we report that MYC copy number gain and increased MYC expression frequently occur in TN-MF and that MYC-directed activation of S100A9, an alarmin protein that plays pivotal roles in inflammation and innate immunity, is necessary and sufficient to drive development and progression of MF. Notably, the MYC-S100A9 circuit provokes a complex network of inflammatory signaling that involves numerous hematopoietic cell types in the bone marrow microenvironment. Accordingly, genetic ablation of S100A9 or treatment with small molecules targeting the MYC-S100A9 pathway effectively ameliorates MF phenotypes, highlighting the MYC-alarmin axis as a novel therapeutic vulnerability for this subgroup of MPNs. Significance: This study establishes that MYC expression is increased in TN-MPNs via trisomy 8, that a MYC-S100A9 circuit manifest in these cases is sufficient to provoke myelofibrosis and inflammation in diverse hematopoietic cell types in the BM niche, and that the MYC-S100A9 circuit is targetable in TN-MPNs.

Third generation quinoline-3-carboxamide transcriptional disrupter of HDAC4, HIF-1α, and MEF-2 signaling for metastatic castration-resistant prostate cancer

BACKGROUND

The quinoline-3-carboxamide, Tasquinimod (TasQ), is orally active as a maintenance therapy with an on-target mechanism-of-action via allosteric binding to HDAC4. This prevents formation of the HDAC4/NCoR1/HDAC3 complex, disrupting HIF-1α transcriptional activation and repressing MEF-2 target genes needed for adaptive survival signaling in the compromised tumor micro environment. In phase 3 clinical testing against metastatic castration-resistant prostate cancer(mCRPC), TasQ (1 mg/day) increased time-to-progression, but not overall survival.

METHODS

TasQ analogs were chemically synthesized and tested for activity compared to the parental compound. These included HDAC4 enzymatic assays, qRT-PCR and western blot analyses of gene and protein expression following treatment, in vitro and in vivo efficacy against multiple prostate cancer models including PDXs, pharmacokinetic analyses,AHR binding and agonist assays, SPR analyses of binding to HDAC4 and NCoR1, RNAseq analysis of in vivo tumors, 3D endothelial sprouting assays, and a targeted kinase screen. Genetic knockout or knockdown controls were used when appropriate.

RESULTS

Here, we document that, on this regimen (1 mg/day), TasQ blood levels are 10-fold lower than the optimal concentration (≥2 μM) needed for anticancer activity, suggesting higher daily doses are needed. Unfortunately, we also demonstrate that TasQ is an arylhydrocarbon receptor (AHR) agonist, which binds with an EC50 of 1 μM to produce unwanted off-target side effects. Therefore, we screened a library of TasQ analogsto maximize on-target versus off-target activity. Using this approach, we identified ESATA-20, which has ~10-fold lower AHR agonism and 5-fold greater potency against prostate cancer patient-derived xenografts.

CONCLUSION

This increased therapeuticindex nominates ESATA-20 as a lead candidate forclinical development as an orally active third generation quinoline-3-carboxamide analog thatretains its on-target ability to disrupt HDAC4/HIF-1α/MEF-2-dependent adaptive survival signaling in the compromisedtumor microenvironment found in mCRPC.

Viral nanoparticle vaccines against S100A9 reduce lung tumor seeding and metastasis

Metastatic cancer accounts for 90% of all cancer-related deaths and continues to be one of the toughest challenges in cancer treatment. A growing body of data indicates that S100A9, a major regulator of inflammation, plays a central role in cancer progression and metastasis, particularly in the lungs, where S100A9 forms a premetastatic niche. Thus, we developed a vaccine against S100A9 derived from plant viruses and virus-like particles. Using multiple tumor mouse models, we demonstrate the effectiveness of the S100A9 vaccine candidates in preventing tumor seeding within the lungs and outgrowth of metastatic disease. The elicited antibodies showed high specificity toward S100A9 without cross-reactivity toward S100A8, another member of the S100A family. When tested in metastatic mouse models of breast cancer and melanoma, the vaccines significantly reduced lung tumor nodules after intravenous challenge or postsurgical removal of the primary tumor. Mechanistically, the vaccines reduce the levels of S100A9 within the lungs and sera, thereby increasing the expression of immunostimulatory cytokines with antitumor function [(interleukin) IL-12 and interferonγ] while reducing levels of immunosuppressive cytokines (IL-10 and transforming growth factorβ). This also correlated with decreased myeloid-derived suppressor cell populations within the lungs. This work has wide-ranging impact, as S100A9 is overexpressed in multiple cancers and linked with poor prognosis in cancer patients. The data presented lay the foundation for the development of therapies and vaccines targeting S100A9 to prevent metastasis.

Non-coding RNAs: emerging roles in the characterization of immune microenvironment and immunotherapy of prostate cancer

Prostate cancer is the most common tumor among men. Although the prognosis for early-stage prostate cancer is good, patients with advanced disease often progress to metastatic castration-resistant prostate cancer (mCRPC), which usually leads to death owing to resistance to existing treatments and lack of long-term effective therapy. In recent years, immunotherapy, especially immune checkpoint inhibitors (ICIs), has made great progress in the treatment of various solid tumors, including prostate cancer. However, the ICIs have only shown modest outcomes in mCRPC compared with other tumors. Previous studies have suggested that the suppressive tumor immune microenvironment (TIME) of prostate cancer leads to poor anti-tumor immune response and tumor resistance to immunotherapy. It has been reported that non-coding RNAs (ncRNAs) are capable of regulating upstream signaling at the transcriptional level, leading to a "cascade of changes" in downstream molecules. As a result, ncRNAs have been identified as an ideal class of molecules for cancer treatment. The discovery of ncRNAs provides a new perspective on TIME regulation in prostate cancer. ncRNAs have been associated with establishing an immunosuppressive microenvironment in prostate cancer through multiple pathways to modulate the immune escape of tumor cells which can promote resistance of prostate cancer to immunotherapy. Targeting these related ncRNAs presents an opportunity to improve the effectiveness of immunotherapy in this patient population.

External Validation of a Prognostic Model of Overall Survival in Men With Chemotherapy-Naïve Metastatic Castration-Resistant Prostate Cancer

PURPOSE

We have previously developed and externally validated a prognostic model of overall survival (OS) in men with metastatic, castration-resistant prostate cancer (mCRPC) treated with docetaxel. We sought to externally validate this model in a broader group of men with docetaxel-naïve mCRPC and in specific subgroups (White, Black, Asian patients, different age groups, and specific treatments) and to classify patients into validated two and three prognostic risk groupings on the basis of the model.

METHODS

Data from 8,083 docetaxel-naïve mCRPC men randomly assigned on seven phase III trials were used to validate the prognostic model of OS. We assessed the predictive performance of the model by computing the time-dependent area under the receiver operating characteristic curve (tAUC) and validated the two-risk (low and high) and three-risk prognostic groups (low, intermediate, and high).

RESULTS

The tAUC was 0.74 (95% CI, 0.73 to 0.75), and when adjusting for the first-line androgen receptor (AR) inhibitor trial status, the tAUC was 0.75 (95% CI, 0.74 to 0.76). Similar results were observed by the different racial, age, and treatment subgroups. In patients enrolled on first-line AR inhibitor trials, the median OS (months) in the low-, intermediate-, and high-prognostic risk groups were 43.3 (95% CI, 40.7 to 45.8), 27.7 (95% CI, 25.8 to 31.3), and 15.4 (95% CI, 14.0 to 17.9), respectively. Compared with the low-risk prognostic group, the hazard ratios for the high- and intermediate-risk groups were 4.3 (95% CI, 3.6 to 5.1; P < .0001) and 1.9 (95% CI, 1.7 to 2.1; P < .0001).

CONCLUSION

This prognostic model for OS in docetaxel-naïve men with mCRPC has been validated using data from seven trials and yields similar results overall and across race, age, and different treatment classes. The prognostic risk groups are robust and can be used to identify groups of patients for enrichment designs and for stratification in randomized clinical trials.

S100A8 and S100A9 in Cancer

S100A8 and S100A9 are Ca²⁺ binding proteins that belong to the S100 family. Primarily expressed in neutrophils and monocytes, S100A8 and S100A9 play critical roles in modulating various inflammatory responses and inflammation-associated diseases. Forming a common heterodimer structure S100A8/A9, S100A8 and S100A9 are widely reported to participate in multiple signaling pathways in tumor cells. Meanwhile, S100A8/A9, S100A8, and S100A9, mainly as promoters, contribute to tumor development, growth and metastasis by interfering with tumor metabolism and the microenvironment. In recent years, the potential of S100A8/A9, S100A9, and S100A8 as tumor diagnostic or prognostic biomarkers has also been demonstrated. In addition, an increasing number of potential therapies targeting S100A8/A9 and related signaling pathways have emerged. In this review, we will first expound on the characteristics of S100A8/A9, S100A9, and S100A8 in-depth, focus on their interactions with tumor cells and microenvironments, and then discuss their clinical applications as biomarkers and therapeutic targets. We also highlight current limitations and look into the future of S100A8/A9 targeted anti-cancer therapy.

Role of myeloid-derived suppressor cells in tumor recurrence

The establishment of primary tumor cells in distant organs, termed metastasis, is the principal cause of cancer mortality and is a crucial therapeutic target in oncology. Thus, it is critical to establish a better understanding of metastatic progression for the future development of improved therapeutic approaches. Indeed, such development requires insight into the timing of tumor cell dissemination and seeding of distant organs resulting in occult lesions. Following dissemination of tumor cells from the primary tumor, they can reside in niches in distant organs for years or decades, following which they can emerge as an overt metastasis. This timeline of metastatic dormancy is regulated by interactions between the tumor, its microenvironment, angiogenesis, and tumor antigen-specific T-cell responses. An improved understanding of the mechanisms and interactions responsible for immune evasion and tumor cell release from dormancy would help identify and aid in the development of novel targeted therapeutics. One such mediator of dormancy is myeloid derived suppressor cells (MDSC), whose number in the peripheral blood (PB) or infiltrating tumors has been associated with cancer stage, grade, patient survival, and metastasis in a broad range of tumor pathologies. Thus, extensive studies have revealed a role for MDSCs in tumor escape from adoptive and innate immune responses, facilitating tumor progression and metastasis; however, few studies have considered their role in dormancy. We have posited that MDSCs may regulate disseminated tumor cells resulting in resurgence of senescent tumor cells. In this review, we discuss clinical studies that address mechanisms of tumor recurrence including from dormancy, the role of MDSCs in their escape from dormancy during recurrence, the development of occult metastases, and the potential for MDSC inhibition as an approach to prolong the survival of patients with advanced malignancies. We stress that assessing the impact of therapies on MDSCs versus other cellular targets is challenging within the multimodality interventions required clinically.

Pathogenic roles of neutrophil-derived alarmins (S100A8/A9) in heart failure: From molecular mechanisms to therapeutic insights

An excessive neutrophil count is recognized as a valuable predictor of inflammation and is associated with a higher risk of adverse cardiac events in patients with heart failure. Our understanding of the effectors used by neutrophils to inflict proinflammatory actions needs to be advanced. Recently, emerging evidence has demonstrated a causative role of neutrophil-derived alarmins (i.e. S100A8/A9) in aggravating cardiac injuries by induction of inflammation. In parallel with the neutrophil count, high circulating levels of S100A8/A9 proteins powerfully predict mortality in patients with heart failure. As such, a deeper understanding of the biological functions of neutrophil-derived S100A8/A9 proteins would offer novel therapeutic insights. Here, the basic biology of S100A8/A9 proteins and their pleiotropic roles in cardiovascular diseases are discussed, focusing on heart failure. We also consider the evidence that therapeutic targeting of S100A8/A9 proteins by the humanized vaccine, antibodies or inhibitors is able to town down inflammatory injuries.

S100A9 promotes glycolytic activity in HER2-positive breast cancer to induce immunosuppression in the tumour microenvironment

Purpose

The purpose of this study was to investigate the correlation between S100 calcium binding protein A9 (S100A9), tumour glycolysis and tumour infiltrating lymphocytes (TIL) in human epidermal growth factor receptor 2 (HER2) - positive breast cancer (BRCA).

Materials and methods

A total of 667 BRCA patients in Xiangya Hospital of Central South University were enrolled in this study. Haematoxylin and eosin (H&E) staining were used to count TIN in tissues. Human breast cancer cell lines (SK-BR-3 cells and BT474 cells) were transfected with S100A9 specific small interfering RNA (siRNA). The expressions of S100A9, glycolytic enzymes and lymphocyte markers were detected by immunohistochemistry (IHC) staining, Western blot and immunofluorescence. Lactate production, glucose consumption and the extracellular acidification rate (ECAR) were detected to assess glycolysis activity.

Results

S100A9 was significantly overexpressed in HER2+ cases. The expressions of phosphoglycerol kinase 1 (PGK1), lactate dehydrogenase A (LDHA) and enolase α (ENO1) were significantly up-regulated in S100A9 dominant tissues. The expressions of PGK1, LDHA and ENO1 detected in S100A9 silenced cell lines were significantly down-regulated. Moreover, S100A9 silencing significantly altered lactate production, glucose uptake and ECAR levels in HER2+ cell lines. Co-expression of S100A9 and c-Myc was detected in HER2+ tissues. The absence of S100A9 greatly hindered β-catenin expression in cell lines, which later induced the phosphorylation of c-Myc.The amount of TILs in cases with abundant S100A9 and LDHA was much greater than in cases with low S100A9 levels and poorer LDHA. TIL deficiency and elevated S100A9 intensity are factors affecting the survival rate of HER2+ BRCA cases.

Conclusions

S100A9 overexpression upregulated the glycolysis activity of tumour cells through the c-Myc-related pathway, suppressing lymphocyte infiltration in the tumour stroma, affecting the efficacy of immune regulation and long-term survival of patients.

Targeting epigenetic regulation for cancer therapy using small molecule inhibitors

Cancer cells display pervasive changes in DNA methylation, disrupted patterns of histone posttranslational modification, chromatin composition or organization and regulatory element activities that alter normal programs of gene expression. It is becoming increasingly clear that disturbances in the epigenome are hallmarks of cancer, which are targetable and represent attractive starting points for drug creation. Remarkable progress has been made in the past decades in discovering and developing epigenetic-based small molecule inhibitors. Recently, epigenetic-targeted agents in hematologic malignancies and solid tumors have been identified and these agents are either in current clinical trials or approved for treatment. However, epigenetic drug applications face many challenges, including low selectivity, poor bioavailability, instability and acquired drug resistance. New multidisciplinary approaches are being designed to overcome these limitations, e.g., applications of machine learning, drug repurposing, high throughput virtual screening technologies, to identify selective compounds with improved stability and better bioavailability. We provide an overview of the key proteins that mediate epigenetic regulation that encompass histone and DNA modifications and discuss effector proteins that affect the organization of chromatin structure and function as well as presently available inhibitors as potential drugs. Current anticancer small-molecule inhibitors targeting epigenetic modified enzymes that have been approved by therapeutic regulatory authorities across the world are highlighted. Many of these are in different stages of clinical evaluation. We also assess emerging strategies for combinatorial approaches of epigenetic drugs with immunotherapy, standard chemotherapy or other classes of agents and advances in the design of novel epigenetic therapies.

Targeting Doublecortin-Like Kinase 1 (DCLK1)-Regulated SARS-CoV-2 Pathogenesis in COVID-19

Host factors play critical roles in SARS-CoV-2 infection-associated pathology and the severity of COVID-19. In this study, we systematically analyzed the roles of SARS-CoV-2-induced host factors, doublecortin-like kinase 1 (DCLK1), and S100A9 in viral pathogenesis. In autopsied subjects with COVID-19 and pre-existing chronic liver disease, we observed high levels of DCLK1 and S100A9 expression and immunosuppressive (DCLK1⁺S100A9⁺CD206⁺) M2-like macrophages and N2-like neutrophils in lungs and livers. DCLK1 and S100A9 expression were rarely observed in normal controls, COVID-19-negative subjects with chronic lung disease, or COVID-19 subjects without chronic liver disease. In hospitalized patients with COVID-19, we detected 2 to 3-fold increased levels of circulating DCLK1⁺S100A9⁺ mononuclear cells that correlated with disease severity. We validated the SARS-CoV-2-dependent generation of these double-positive immune cells in coculture. SARS-CoV-2-induced DCLK1 expression correlated with the activation of β-catenin, a known regulator of the DCLK1 promoter. Gain and loss of function studies showed that DCLK1 kinase amplified live virus production and promoted cytokine, chemokine, and growth factor secretion by peripheral blood mononuclear cells. Inhibition of DCLK1 kinase blocked pro-inflammatory caspase-1/interleukin-1β signaling in infected cells. Treatment of SARS-CoV-2-infected cells with inhibitors of DCLK1 kinase and S100A9 normalized cytokine/chemokine profiles and attenuated DCLK1 expression and β-catenin activation. In conclusion, we report previously unidentified roles of DCLK1 in augmenting SARS-CoV-2 viremia, inflammatory cytokine expression, and dysregulation of immune cells involved in innate immunity. DCLK1 could be a potential therapeutic target for COVID-19, especially in patients with underlying comorbid diseases associated with DCLK1 expression.

IMPORTANCE High mortality in COVID-19 is associated with underlying comorbidities such as chronic liver diseases. Successful treatment of severe/critical COVID-19 remains challenging. Herein, we report a targetable host factor, DCLK1, that amplifies SARS-CoV-2 production, cytokine secretion, and inflammatory pathways via activation of β-catenin(p65)/DCLK1/S100A9/NF-κB signaling. Furthermore, we observed in the lung, liver, and blood an increased prevalence of immune cells coexpressing DCLK1 and S100A9, a myeloid-derived proinflammatory protein. These cells were associated with increased disease severity in COVID-19 patients. Finally, we used a novel small-molecule inhibitor of DCLK1 kinase (DCLK1-IN-1) and S100A9 inhibitor (tasquinimod) to decrease virus production in vitro and normalize hyperinflammatory responses known to contribute to disease severity in COVID-19.

Overcoming Immune Resistance With Radiation Therapy in Prostate Cancer

Prostate cancer is the second most common cancer in men and represents a significant healthcare burden worldwide. Therapeutic options in the metastatic castration-resistant setting remain limited, despite advances in androgen deprivation therapy, precision medicine and targeted therapies. In this review, we summarize the role of immunotherapy in prostate cancer and offer perspectives on opportunities for future development, based on current knowledge of the immunosuppressive tumor microenvironment. Furthermore, we discuss the potential for synergistic therapeutic strategies with modern radiotherapy, through modulation of the tumor microenvironment. Emerging clinical and pre-clinical data suggest that radiation can convert immune desert tumors into an inflamed immunological hub, potentially sensitive to immunotherapy.

Immunosuppressive cells in cancer: mechanisms and potential therapeutic targets

Immunotherapies like the adoptive transfer of gene-engineered T cells and immune checkpoint inhibitors are novel therapeutic modalities for advanced cancers. However, some patients are refractory or resistant to these therapies, and the mechanisms underlying tumor immune resistance have not been fully elucidated. Immunosuppressive cells such as myeloid-derived suppressive cells, tumor-associated macrophages, tumor-associated neutrophils, regulatory T cells (Tregs), and tumor-associated dendritic cells are critical factors correlated with immune resistance. In addition, cytokines and factors secreted by tumor cells or these immunosuppressive cells also mediate the tumor progression and immune escape of cancers. Thus, targeting these immunosuppressive cells and the related signals is the promising therapy to improve the efficacy of immunotherapies and reverse the immune resistance. However, even with certain success in preclinical studies or in some specific types of cancer, large perspectives are unknown for these immunosuppressive cells, and the related therapies have undesirable outcomes for clinical patients. In this review, we comprehensively summarized the phenotype, function, and potential therapeutic targets of these immunosuppressive cells in the tumor microenvironment.

Single Cell RNA Sequencing Identifies a Unique Inflammatory Macrophage Subset as a Druggable Target for Alleviating Acute Kidney Injury

Acute kidney injury (AKI) is a complex clinical disorder associated with poor outcomes. Targeted regulation of the degree of inflammation has been a potential strategy for AKI management. Macrophages are the main effector cells of kidney inflammation. However, macrophage heterogeneity in ischemia reperfusion injury induced AKI (IRI-AKI) remains unclear. Using single-cell RNA sequencing of the mononuclear phagocytic system in the murine IRI model, the authors demonstrate the complementary roles of kidney resident macrophages (KRMs) and monocyte-derived infiltrated macrophages (IMs) in modulating tissue inflammation and promoting tissue repair. A unique population of S100a9hi Ly6chi IMs is identified as an early responder to AKI, mediating the initiation and amplification of kidney inflammation. Kidney infiltration of S100A8/A9+ macrophages and the relevance of renal S100A8/A9 to tissue injury is confirmed in human AKI. Targeting the S100a8/a9 signaling with small-molecule inhibitors exhibits renal protective effects represented by improved renal function and reduced mortality in bilateral IRI model, and decreased inflammatory response, ameliorated kidney injury, and improved long-term outcome with decreased renal fibrosis in the unilateral IRI model. The findings support S100A8/A9 blockade as a feasible and clinically relevant therapy potentially waiting for translation in human AKI.

Immunotherapy in Advanced Prostate Cancer-Light at the End of the Tunnel?

Immunotherapeutic treatment approaches are now an integral part of the treatment of many solid tumors. However, attempts to integrate immunotherapy into the treatment of prostate cancer have been disappointing so far. This is due to a highly immunosuppressive, "cold" tumor microenvironment, which is characterized, for example, by the absence of cytotoxic T cells, an increased number of myeloid-derived suppressor cells or regulatory T cells, a decreased number of tumor antigens, or a defect in antigen presentation. The consequence is a reduced efficacy of many established immunotherapeutic treatments such as checkpoint inhibitors. However, a growing understanding of the underlying mechanisms of tumor-immune system interactions raises hopes that immunotherapeutic strategies can be optimized in the future. The aim of this review is to provide an overview of the current status and future directions of immunotherapy development in prostate cancer. Background information on immune response and tumor microenvironment will help to better understand current therapeutic strategies under preclinical and clinical development.

Correlation Between Imaging-Based Intermediate Endpoints and Overall Survival in Men With Metastatic Castration-Resistant Prostate Cancer: Analysis of 28 Randomized Trials Using the Prostate Cancer Clinical Trials Working Group (PCWG2) Criteria in 16,511 Patients

INTRODUCTION/BACKGROUND

Radiographic progression-free survival (rPFS) based on Prostate Cancer Working Group 2 (PCWG2) has been increasingly used as a meaningful imaging-based intermediate endpoint (IBIE) for overall survival (OS) in patients with metastatic castration-resistant prostate cancer (mCRPC). In randomized phase III trials, rPFS showed good correlation with OS at the individual trial level. We aimed to assess the correlation between the hazard ratios (HR) of IBIE and OS among PCWG2-based randomized trials.

MATERIALS AND METHODS

PubMed and EMBASE databases were systematically searched for randomized trials evaluating systemic treatments on mCRPC using PCWG2 up to April 15, 2020. Hazard ratios for OS and IBIEs were extracted and their correlation was assessed using weighted linear regression. Subgroup analyses were performed according to various clinical settings: prior chemotherapy, drug category, type of IBIE (rPFS vs. composite IBIE, latter defined as progression by imaging and one or a combination of PSA, pain, skeletal-related events, and performance status), and publication year.

RESULTS

Twenty-eight phase II-III randomized trials (16,511 patients) were included. Correlation between OS and IBIE was good (R² = 0.57, 95% confidence interval [CI], 0.35-0.78). Trials using rPFS showed substantially higher correlation than those using a composite IBIE (R² = 0.58, 95% CI, 0.32-0.82 vs. 0.00, 95% CI, -0.01 to 0.01). Correlations between OS and IBIE in other subgroups were at least moderate in nearly all subgroups (R² = 0.32-0.91).

CONCLUSION

IBIEs in the era of PCWG2 correlate well with OS in randomized trials for systemic drugs in patients with mCRPC. PCWG2-based rPFS should be used instead of a composite IBIE that includes PSA and other clinical variables.

The evolving role of immune cells in prostate cancer

Prostate cancer is the most commonly diagnosed cancer and the second leading cause of cancer-related death among men in western countries. Androgen deprivation therapy (ADT) is considered the standard therapy for recurrent prostate cancer; however, this therapy may lead to ADT resistance and tumor progression, which seems to be regulated by epithelial-mesenchymal transition (EMT) and/or neuroendocrine differentiation (NED). In addition, recent data suggested the involvement of either adaptive or innate infiltrated immune cells in the initiation, progression, metastasis, and treatment of prostate cancer. In this review, we outlined the characteristics and roles of these immune cells in the initiation, progression, metastasis, and treatments of prostate cancer. We also summarized the current therapeutic strategies in targeting immune cells of the prostate tumor microenvironment.

Macrophages as a Therapeutic Target in Metastatic Prostate Cancer: A Way to Overcome Immunotherapy Resistance?

Prostate cancer (PC) is the most common malignancy and the fifth cause of cancer death in men. The treatment for localized or locally advanced stages offers a high probability of cure. Even though the therapeutic landscape has significantly improved over the last decade, metastatic PC (mPC) still has a poor prognosis mainly due to the development of therapy resistance. In this context, the use of immunotherapy alone or in combination with other drugs has been explored in recent years. However, T-cell directed immune checkpoint inhibitors (ICIs) have shown limited activity with inconclusive results in mPC patients, most likely due to the highly immunosuppressive PC tumor microenvironment (TME). In this scenario, targeting macrophages, a highly abundant immunosuppressive cell type in the TME, could offer a new therapeutic strategy to improve immunotherapy efficacy. In this review, we summarize the growing field of macrophage-directed immunotherapies and discuss how these could be applied in the treatment of mPC, focusing on their combination with ICIs.

Prostate cancer immunotherapy

INTRODUCTION

Medical treatment for prostate cancer (PC) targets hormonal pathways used by malignant cells. Research advances aided in gaining knowledge about implicated molecular pathways and opened the way for establishment of new types of therapies by modifying immunological mechanisms. The aim of this review is to present completed and ongoing research projects regarding PC immunotherapy.

AREAS COVERED

A literature search was conducted in PubMed/MEDLINE, Scopus, Cochrane Central Register of Controlled Trials, and https://www.clinicaltrials.gov/ from inception until 07/2021, to identify completed or ongoing Phase III trials regarding several immunotherapies against PC. Studies on vaccine therapies, CTLA-4 inhibitors, PD-1/PD-L1 inhibitors, PARP inhibitors, PSMA-targeted therapies, and tyrosine kinase inhibitors were considered eligible.

EXPERT OPINION

Although many molecules are being tested against PC cells, only sipuleucel-T has gain approval in the USA. The main reason for this delay in establishing immunotherapy as a standard option for managing PC is the heterogeneity and tumor immune microenvironment complexities. Ipilimumab and olaparib were proved to prolong overall survival significantly against placebo, but a lot of research is going on to identify which patients and at what stage of disease will benefit the most before incorporating them in clinical practice. More recent options such as PSMA-targeted treatments are currently evaluated.

ARTICLE HIGHLIGHTS

Intense research performed on immunotherapy for prostate cancer.Vaccine therapy with sipuleucel-T, the only approved immunotherapy for prostate cancer.Ipilimumab shows survival benefits.Olaparib shows survival benefits.Findings should be confirmed on further trials to identify target population characteristics and proper disease stage.Immunotherapy is not yet a standard due to tumor environment complex interaction between immune system and malignant cells.

Myeloid-derived suppressor cells as immunosuppressive regulators and therapeutic targets in cancer

Myeloid-derived suppressor cells (MDSCs) are a heterogenic population of immature myeloid cells with immunosuppressive effects, which undergo massive expansion during tumor progression. These cells not only support immune escape directly but also promote tumor invasion via various non-immunological activities. Besides, this group of cells are proved to impair the efficiency of current antitumor strategies such as chemotherapy, radiotherapy, and immunotherapy. Therefore, MDSCs are considered as potential therapeutic targets for cancer therapy. Treatment strategies targeting MDSCs have shown promising outcomes in both preclinical studies and clinical trials when administrated alone, or in combination with other anticancer therapies. In this review, we shed new light on recent advances in the biological characteristics and immunosuppressive functions of MDSCs. We also hope to propose an overview of current MDSCs-targeting therapies so as to provide new ideas for cancer treatment.

Histone Deacetylase 4 Controls Extracellular Matrix Production in Orbital Fibroblasts from Graves' Ophthalmopathy Patients

Background: Graves' ophthalmopathy (GO) is an autoimmune eye disease with the characteristic symptoms of eyelid retraction and proptosis. Orbital fibroblast activation induced by platelet-derived growth factor-BB (PDGF-BB) stimulation plays a crucial role in GO pathogenesis, leading to excessive proliferation and extracellular matrix production by orbital fibroblasts. Currently, GO treatment options remain limited and novel therapies including targeted drugs are needed. Histone deacetylases (HDACs) are associated with the development and progression of several cancers and autoimmune diseases by epigenetically controlling gene transcription, and HDAC inhibitors (HDACis) may have therapeutic potential. Nevertheless, the role of HDACs in orbital fibroblasts from GO is unknown. Therefore, we studied the expression of HDACs as well as their contribution to extracellular matrix production in orbital fibroblasts. Methods: Orbital tissues were obtained from GO patients (n = 18) who underwent decompression surgery with approval from the Institutional Review Board of the Faculty of Medicine (Protocol number 401/61), Chulalongkorn University (Bangkok, Thailand). Furthermore, orbital tissue was obtained from control patients (n = 3) without inflammatory or thyroid disease who underwent surgery for cosmetic reasons. Orbital fibroblast cultures were established from the orbital tissues. HDAC mRNA and protein expression in orbital fibroblasts was analyzed by reverse transcription-quantitative real-time PCR and Western blot. PDGF-BB-activated orbital fibroblast and orbital tissues were treated with HDACis or HDAC4 small-interfering RNA. Results: PDGF-BB-stimulated orbital fibroblasts had upregulated HDAC4 mRNA and protein expression. HDAC4 mRNA expression was significantly higher in GO compared with healthy control orbital fibroblasts. Histone H3 lysine 9 acetylation (H3K9ac) decreased upon PDGF-BB stimulation. Treatment with HDAC4i (tasquinimod) and HDAC4/5i (LMK-235) significantly decreased both proliferation and hyaluronan production in PDGF-BB-stimulated orbital fibroblasts. HDAC4 silencing reduced mRNA expression of hyaluronan synthase 2 (HAS2), collagen type I alpha 1 chain (COL1A1), Ki67, and α-smooth muscle actin (α-SMA), as well as hyaluronan production in PDGF-BB-stimulated orbital fibroblasts. Tasquinimod significantly reduced HAS2 and α-SMA mRNA expression in whole orbital tissue. Conclusion: Our data indicated, for the first time, that altered HDAC4 regulation along with H3K9 hypoacetylation might represent a mechanism that contributes to excessive proliferation and extracellular matrix production by orbital fibroblasts in GO. HDAC4 might represent a novel target for GO therapy.

Reactivation of dormant tumor cells by modified lipids derived from stress-activated neutrophils

Tumor recurrence years after seemingly successful treatment of primary tumors is one of the major causes of mortality in patients with cancer. Reactivation of dormant tumor cells is largely responsible for this phenomenon. Using dormancy models of lung and ovarian cancer, we found a specific mechanism, mediated by stress and neutrophils, that may govern this process. Stress hormones cause rapid release of proinflammatory S100A8/A9 proteins by neutrophils. S100A8/A9 induce activation of myeloperoxidase, resulting in accumulation of oxidized lipids in these cells. Upon release from neutrophils, these lipids up-regulate the fibroblast growth factor pathway in tumor cells, causing tumor cell exit from the dormancy and formation of new tumor lesions. Higher serum concentrations of S100A8/A9 were associated with shorter time to recurrence in patients with lung cancer after complete tumor resection. Targeting of S100A8/A9 or β2-adrenergic receptors abrogated stress-induced reactivation of dormant tumor cells. These observations demonstrate a mechanism linking stress and specific neutrophil activation with early recurrence in cancer.

The S100 Protein Family as Players and Therapeutic Targets in Pulmonary Diseases

The S100 protein family consists of over 20 members in humans that are involved in many intracellular and extracellular processes, including proliferation, differentiation, apoptosis, Ca₂⁺ homeostasis, energy metabolism, inflammation, tissue repair, and migration/invasion. Although there are structural similarities between each member, they are not functionally interchangeable. The S100 proteins function both as intracellular Ca²⁺ sensors and as extracellular factors. Dysregulated responses of multiple members of the S100 family are observed in several diseases, including the lungs (asthma, chronic obstructive pulmonary disease, idiopathic pulmonary fibrosis, cystic fibrosis, pulmonary hypertension, and lung cancer). To this degree, extensive research was undertaken to identify their roles in pulmonary disease pathogenesis and the identification of inhibitors for several S100 family members that have progressed to clinical trials in patients for nonpulmonary conditions. This review outlines the potential role of each S100 protein in pulmonary diseases, details the possible mechanisms observed in diseases, and outlines potential therapeutic strategies for treatment.

High Monocyte Count and Expression of S100A9 and S100A12 in Peripheral Blood Mononuclear Cells Are Associated with Poor Outcome in Patients with Metastatic Prostate Cancer

Increasing evidence indicates calcium-binding S100 protein involvement in inflammation and tumor progression. In this prospective study, we evaluated the mRNA levels of two members of this family, S100A9 and S100A12, in peripheral blood mononuclear cells (PBMCs) in a cohort of 121 prostate cancer patients using RT-PCR. Furthermore, monocyte count was determined by flow cytometry. By stratifying patients into different risk groups, according to TNM stage, Gleason score and PSA concentration at diagnosis, expression of S100A9 and S100A12 was found to be significantly higher in patients with metastases compared to patients without clinically detectable metastases. In line with this, we observed that the protein levels of S100A9 and S100A12 in plasma were higher in patients with advanced disease. Importantly, in patients with metastases at diagnosis, high monocyte count and high levels of S100A9 and S100A12 were significantly associated with short progression free survival (PFS) after androgen deprivation therapy (ADT). High monocyte count and S100A9 levels were also associated with short cancer-specific survival, with monocyte count providing independent prognostic information. These findings indicate that circulating levels of monocytes, as well as S100A9 and S100A12, could be biomarkers for metastatic prostate cancer associated with particularly poor prognosis.

Underlying mechanisms and drug intervention strategies for the tumour microenvironment

Cancer occurs in a complex tissue environment, and its progression depends largely on the tumour microenvironment (TME). The TME has a highly complex and comprehensive system accompanied by dynamic changes and special biological characteristics, such as hypoxia, nutrient deficiency, inflammation, immunosuppression and cytokine production. In addition, a large number of cancer-associated biomolecules and signalling pathways are involved in the above bioprocesses. This paper reviews our understanding of the TME and describes its biological and molecular characterization in different stages of cancer development. Furthermore, we discuss in detail the intervention strategies for the critical points of the TME, including chemotherapy, targeted therapy, immunotherapy, natural products from traditional Chinese medicine, combined drug therapy, etc., providing a scientific basis for cancer therapy from the perspective of key molecular targets in the TME.

Role of RAGE and Its Ligands on Inflammatory Responses to Brain Tumors

Gliomas, the most common form of brain cancer, can range from relatively slow-growing low-grade to highly aggressive glioblastoma that has a median overall survival of only 15 months despite multimodal standard therapy. Although immunotherapy with checkpoint inhibitors has significantly improved patient survival for some cancers, to date, these agents have not shown consistent efficacy against malignant gliomas. Therefore, there is a pressing need to better understand the impact of host inflammatory responses on the efficacy of emerging immunotherapy approaches for these resistant tumors. RAGE is a multi-ligand pattern recognition receptor that is activated in various inflammatory states such as diabetes, Alzheimer's disease, cystic fibrosis, and cancer. Low levels of RAGE can be found under normal physiological conditions in neurons, immune cells, activated endothelial, and vascular smooth muscle cells, but it is over-expressed under chronic inflammation due to the accumulation of its ligands. RAGE binds to a range of damage-associated molecular pattern molecules (DAMPs) including AGEs, HMGB1, S100s, and DNA which mediate downstream cellular responses that promote tumor growth, angiogenesis, and invasion. Both in vitro and in vivo studies have shown that inhibition of RAGE signaling can disrupt inflammation and cancer progression and metastasis. Here, we will review our current understanding of the role of RAGE pathway on glioma progression and how it could be exploited to improve the efficacy of immunotherapy approaches.

Application of Anti-Inflammatory Agents in Prostate Cancer

Chronic inflammation is a major cause of human cancers. The environmental factors, such as microbiome, dietary components, and obesity, provoke chronic inflammation in the prostate, which promotes cancer development and progression. Crosstalk between immune cells and cancer cells enhances the secretion of intercellular signaling molecules, such as cytokines and chemokines, thereby orchestrating the generation of inflammatory microenvironment. Tumor-associated macrophages (TAMs) and myeloid-derived suppressor cells (MDSCs) play pivotal roles in inflammation-associated cancer by inhibiting effective anti-tumor immunity. Anti-inflammatory agents, such as aspirin, metformin, and statins, have potential application in chemoprevention of prostate cancer. Furthermore, pro-inflammatory immunity-targeted therapies may provide novel strategies to treat patients with cancer. Thus, anti-inflammatory agents are expected to suppress the “vicious cycle” created by immune and cancer cells and inhibit cancer progression. This review has explored the immune cells that facilitate prostate cancer development and progression, with particular focus on the application of anti-inflammatory agents for both chemoprevention and therapeutic approach in prostate cancer.

The New Era of Cancer Immunotherapy: Targeting Myeloid-Derived Suppressor Cells to Overcome Immune Evasion

Suppression of antitumor immune responses is one of the main mechanisms by which tumor cells escape from destruction by the immune system. Myeloid-derived suppressor cells (MDSCs) represent the main immunosuppressive cells present in the tumor microenvironment (TME) that sustain cancer progression. MDSCs are a heterogeneous group of immature myeloid cells with a potent activity against T-cell. Studies in mice have demonstrated that MDSCs accumulate in several types of cancer where they promote invasion, angiogenesis, and metastasis formation and inhibit antitumor immunity. In addition, different clinical studies have shown that MDSCs levels in the peripheral blood of cancer patients correlates with tumor burden, stage and with poor prognosis in multiple malignancies. Thus, MDSCs are the major obstacle to many cancer immunotherapies and their targeting may be a beneficial strategy for improvement the efficiency of immunotherapeutic interventions. However, the great heterogeneity of these cells makes their identification in human cancer very challenging. Since both the phenotype and mechanisms of action of MDSCs appear to be tumor-dependent, it is important to accurately characterized the precise MDSC subsets that have clinical relevance in each tumor environment to more efficiently target them. In this review we summarize the phenotype and the suppressive mechanisms of MDSCs populations expanded within different tumor contexts. Further, we discuss about their clinical relevance for cancer diagnosis and therapy.

Friend or Foe: S100 Proteins in Cancer

S100 proteins are widely expressed small molecular EF-hand calcium-binding proteins of vertebrates, which are involved in numerous cellular processes, such as Ca²⁺ homeostasis, proliferation, apoptosis, differentiation, and inflammation. Although the complex network of S100 signalling is by far not fully deciphered, several S100 family members could be linked to a variety of diseases, such as inflammatory disorders, neurological diseases, and also cancer. The research of the past decades revealed that S100 proteins play a crucial role in the development and progression of many cancer types, such as breast cancer, lung cancer, and melanoma. Hence, S100 family members have also been shown to be promising diagnostic markers and possible novel targets for therapy. However, the current knowledge of S100 proteins is limited and more attention to this unique group of proteins is needed. Therefore, this review article summarises S100 proteins and their relation in different cancer types, while also providing an overview of novel therapeutic strategies for targeting S100 proteins for cancer treatment.

Patient Experience Captured by Quality-of-Life Measurement in Oncology Clinical Trials

IMPORTANCE

Quality of life (QoL) is an important consideration in cancer medicine, especially because drugs are becoming more costly and may only result in modest gains in overall survival. However, there has been no descriptive analysis for the points at which QoL is measured in cancer trials.

OBJECTIVE

To estimate the prevalence of studies that measure QoL at different points and see how many studies measure QoL for the entirety of a patient's life.

DESIGN, SETTING, AND PARTICIPANTS

This cross-sectional analysis includes all articles on oncology clinical trials in the 3 highest-impact oncology journals, published between July 2015 and June 2018, that reported QoL outcomes.

MAIN OUTCOMES AND MEASURES

Data were abstracted on when QoL was assessed and the characteristics of these studies.

RESULTS

For all 149 studies that met inclusion criteria, QoL assessment was high during treatment (104 articles [69.8%]), during follow-up (81 articles [54.4%]), and after the end of the intervention (68 articles [45.6%]). In 5 of the 149 studies (3.4%), QoL was assessed until death, including in only 1 of the 74 studies on metastatic or incurable cancers. Among these 5 studies, only 1 (20%) used a drug intervention, 1 (20%) used a behavioral intervention, and 2 (40%) used a radiation intervention; only 1 of 5 was in the metastatic setting. The number of studies that reported a positive QoL outcome (ie, QoL outcome was more favorable in the intervention group than in the control group) was between 42 of 81 articles (51.9%) and 16 of 28 articles (57.1%) for most QoL assessment points but only 1 of 5 articles (20%) for studies measuring QoL until death.

CONCLUSIONS AND RELEVANCE

This study found that most clinical trials assessed QoL during the treatment or intervention and often during a given amount of follow-up but infrequently assessed QoL on disease progression and rarely followed QoL until the end of the patient's life. Most studies reporting QoL until the end of life reported worse QoL outcomes for the intervention group than the control group. Future research and policy recommendations should consider not just short-term QoL outcomes but QoL outcomes throughout the patient's cancer care.

Crosstalk between myeloid-derived suppressor cells and the immune system in prostate cancer

Prostate cancer is the second most common cancer and the fifth leading cause of cancer-associated death in men. Previous studies have revealed a surprising ability for an immature population of myeloid cells called myeloid-derived suppressor cells (MDSCs) in the commencement and development of many tumors, including those of prostate cancer. Herein, the molecular and cellular changes of MDSCs in prostate cancer in both human and nonhuman models are reviewed. The suppressive function of MDSCs are also discussed with a particular focus on the role of IL-6 and JAK/STAT3 signaling pathways in the induction of their suppressive activity. Ultimately, a brief review of MDSC-targeting approaches for potential cancer therapy is presented.

Phase 1b trial of docetaxel, prednisone, and pazopanib in men with metastatic castration-resistant prostate cancer

BACKGROUND

Docetaxel prednisone is a standard of care for men with metastatic castration-resistant prostate cancer (mCRPC), and plasma vascular endothelial growth factor (VEGF) levels are a poor prognostic factor in this population; therefore, we evaluated the combination of docetaxel prednisone with pazopanib, an oral VEGF receptor inhibitor, for safety and preliminary efficacy.

METHODS

This is a two-site phase 1b Department of Defense Prostate Cancer Clinical Trials Consortium trial of docetaxel, prednisone, and pazopanib once daily and ongoing androgen deprivation therapy and prophylactic pegfilgrastim in men with mCRPC. The primary endpoint was safety and the determination of a maximum tolerated dose (MTD) through a dose-escalation and expansion design; secondary endpoints included progression-free and overall survival (OS), prostate specific antigen (PSA) declines, radiographic responses, and pharmacokinetic and plasma angiokine biomarker analyses.

RESULTS

Twenty-five men were treated over six dose levels. Pegfilgrastim was added to the regimen after myelosuppression limited dose escalation. With pegfilgrastim, our target MTD of docetaxel 75 mg/m² q3 weeks; prednisone 10 mg daily; and pazopanib 800 mg daily was reached. Eleven additional patients were accrued at this dose level for a total of 36 patients. Dose-limiting toxicities included neutropenia, syncope, and hypertension. Three deaths attributed to study treatment occurred. The objective response rate was 31%; median PFS was 14.1 months (95% confidence interval [CI]: 7.1 and 22.2); and OS was 18.6 months (95% CI: 11.8 and 22.2).

CONCLUSIONS

The combination of docetaxel, prednisone, and pazopanib (with pegfilgrastim) was tolerable at full doses and demonstrated promising efficacy in a relatively poor risk patients with mCRPC. Further development of predictive biomarkers may enrich for patients who receive clinical benefit from this regimen.

The Evolving Systemic Treatment Landscape for Patients with Advanced Prostate Cancer

Prostate cancer (PC) is a major health issue in developed countries, with, on the one hand, men suffering from sequelae related to unnecessary treatment of non-lethal PC, and, on the other hand, still dying because of advanced PC that progresses to castration-resistant disease. Systemic treatment is the mainstay of therapy of castration-resistant PC (CRPC). To date, a multitude of systemic agents have been tested and many of these have failed to provide a clinically meaningful benefit in CRPC, while others have been approved by the US Food and Drug Administration and/or the European Medicines Agency, including antiandrogen hormonal drugs (abiraterone, enzalutamide, apalutamide), chemotherapy (docetaxel and cabazitaxel), immunotherapy (Sipuleucel-T), and radiopharmaceutical (Radium-223) agents. In this review, systemic treatments regarded as most likely to have an impact in clinical practice are presented and discussed. In addition to the pivotal clinical studies, selected retrospective and non-randomized clinical trials are also discussed if deemed to have an impact on clinical practice or future research. A comprehensive appraisal of the expanding landscape of systemic therapies for advanced PC is provided from an expert perspective, with a focus on novel classification and diagnostic tools that have been paving the way for the development of precision medicine in PC.

Phase 3 Assessment of the Automated Bone Scan Index as a Prognostic Imaging Biomarker of Overall Survival in Men With Metastatic Castration-Resistant Prostate Cancer: A Secondary Analysis of a Randomized Clinical Trial

Importance

Prostate cancer commonly metastasizes to bone, and bone metastases are associated with pathologic fractures, pain, and reduced survival. Bone disease is routinely visualized using the technetium Tc 99m (99mTc) bone scan; however, the standard interpretation of bone scan data relies on subjective manual assessment of counting metastatic lesion numbers. There is an unmet need for an objective and fully quantitative assessment of bone scan data.

Objective

To clinically assess in a prospectively defined analysis plan of a clinical trial the automated Bone Scan Index (aBSI) as an independent prognostic determinant of overall survival (OS) in men with metastatic castration-resistant prostate cancer (mCRPC).

Design, Setting, and Participants

This investigation was a prospectively planned analysis of the aBSI in a phase 3 multicenter randomized, double-blind, placebo-controlled clinical trial of tasquinimod (10TASQ10). Men with bone metastatic chemotherapy-naïve CRPC were recruited at 241 sites in 37 countries between March 2011 and August 2015. The statistical analysis plan to clinically evaluate the aBSI was prospectively defined and locked before unmasking of the 10TASQ10 study. The analysis of aBSI was conducted between May 25, 2016, and June 3, 2017.

Main Outcomes and Measures

The associations of baseline aBSI with OS, radiographic progression-free survival (rPFS), time to symptomatic progression, and time to opiate use for cancer pain.

Results

Of the total 1245 men enrolled, 721 were evaluable for the aBSI. The mean (SD) age (available for 719 men) was 70.6 (8.0) years (age range, 47-90 years). The aBSI population was representative of the total study population based on baseline characteristics. The aBSI (median, 1.07; range, 0-32.60) was significantly associated with OS (hazard ratio [HR], 1.20; 95% CI, 1.14-1.26; P < .001). The median OS by aBSI quartile (lowest to highest) was 34.7, 27.3, 21.7, and 13.3 months, respectively. The discriminative ability of the aBSI (C index, 0.63) in prognosticating OS was significantly higher than that of the manual lesion counting (C index, 0.60) (P = .03). In a multivariable survival model, a higher aBSI remained independently associated with OS (HR, 1.06; 95% CI, 1.01-1.11; P = .03). A higher aBSI was also independently associated with time to symptomatic progression (HR, 1.18; 95% CI, 1.13-1.23; P < .001) and time to opiate use for cancer pain (HR, 1.21; 95% CI, 1.14-1.30; P < .001).

Conclusions and Relevance

To date, this investigation is the largest prospectively analyzed study to validate the aBSI as an independent prognostic imaging biomarker of survival in mCRPC. These data support the prognostic utility of the aBSI as an objective imaging biomarker in the design and eligibility of clinical trials of systemic therapies for patients with mCRPC.

Trial Registration

ClinicalTrials.gov Identifier: NCT01234311.

Utilizing precision medicine to modulate the prostate tumor microenvironment and enhance immunotherapy

The last two decades of cancer research have seen two major advancements in our ability to treat cancer: precision medicine and immunotherapy. While these approaches have shown striking anticancer efficacy in numerous malignancies, they have not shown similar success and applicability in advanced prostate cancer patients. The fields of precision medicine and immunotherapy have come to realize that targeted therapies are capable of not only inhibiting tumor cell growth, but also promoting antitumor immunity by modulating the tumor microenvironment. Here we examine how personalized medicine can be used to target the tumor immune microenvironment in prostate cancer, with the goal of enhancing clinical responses to immunotherapy.

Quality-of-Life Assessment and Reporting in Prostate Cancer: Systematic Review of Phase 3 Trials Testing Anticancer Drugs Published Between 2012 and 2018

Quality of life (QoL) is not included among the end points in many studies, and QoL results are underreported in many phase 3 oncology trials. We performed a systematic review to describe QoL prevalence and heterogeneity in QoL reporting in recently published prostate cancer phase 3 trials. A PubMed search was performed to identify primary publications of randomized phase 3 trials testing anticancer drugs in prostate cancer, issued between 2012 and 2018. We analyzed QoL inclusion among end points, presence of QoL results, and methodology of QoL analysis. Seventy-two publications were identified (15 early-stage, 20 advanced hormone-sensitive, and 37 castration-resistant prostate cancer [CRPC]). QoL was not listed among study end points in 23 studies (31.9%) (40.0% early stage, 40.0% advanced hormone sensitive, and 24.3% CRPC). QoL results were absent in 15 (30.6%) of 49 primary publications of trials that included QoL among end points. Overall, as a result of absent end point or unpublished results, QoL data were lacking in 38 (52.8%) primary publications (53.3% early stage, 55.0% in advanced hormone sensitive, and 51.4% in CRPC). The most commonly used QoL tools were Functional Assessment of Cancer Therapy-Prostate (FACT-P) (21, 53.8%) and European Organization for Research and Treatment of Cancer Quality of Life Questionnaire-Core 30 (EORTC QLQ-C30) (14, 35.9%); most common methods of analysis were mean changes or mean scores (28, 71.8%), time to deterioration (14, 35.9%), and proportion of patients with response (10, 25.6%). In conclusion, QoL data are lacking in a not negligible proportion of recently published phase 3 trials in prostate cancer, although the presence of QoL results is better in positive trials, especially in CRPC. The methodology of QoL analysis is heterogeneous for type of instruments, analysis, and presentation of results.

Measuring the unmeasurable: automated bone scan index as a quantitative endpoint in prostate cancer clinical trials

BACKGROUND

Up to 90% of men with metastatic castration-resistant prostate cancer (mCRPC) will have a distribution of disease that includes bone metastases demonstrated on a Technetium-99m (^99mTc-MDP) bone scan. The Prostate Cancer Working Group 2 and 3 Consensus Criteria standardized the criteria for assessing progression based on the development of new lesions. These criteria have been recognized by regulatory authorities for drug approval. The bone scan index (BSI) is a method to quantitatively measure the burden of bony disease, and can assess both disease progression and regression. The automated BSI (aBSI) is a method of computer analysis to assess BSI, and is being qualified as a clinical trials endpoint.

METHODS

Manual searching was used to identify the literature on BSI and aBSI. We summarize the most relevant aspects of the retrospective and prospective studies evaluating aBSI measurements, and provide a critical discussion on the potential advantages and caveats of aBSI.

RESULTS

The development of neural artificial networks (EXINI boneBSI) to automatically determine the BSI reduces the turnaround time for assessing BSI with high reproducibility and accuracy. Several studies showed that the concordance between aBSI and BSI, as well as the interobserver concordance of aBSI, was >0.95. In a phase 3 assessment of aBSI, a doubling value increased the risk of death in 20%, pre-treatment aBSI values independently correlated with overall survival (OS) and time to symptomatic progression. Retrospective studies suggest that a decrease in aBSI after treatment may correlate with higher survival when compared with increasing aBSI.

CONCLUSIONS

aBSI provides a quantitative measurement that is feasible, reproducible, and in analyses to date correlates with OS and symptomatic progression. These findings support the aBSI to risk-stratify men with mCRPC for clinical trial enrollment. Future studies quantifying aBSI change over time as an intermediate endpoint for evaluating new systemic therapies are needed.

Radionuclide Therapy of Metastatic Prostate Cancer

The current mainstay of treatment in metastatic prostate cancer is based on hormonal manipulations. Standard androgen deprivation therapy and novel androgen axis drugs are commonly well tolerable and can stabilize metastatic hormone-sensitive prostate cancers for years. However, metastatic castration-resistant prostate cancer is still challenging to treat. Except taxanes, prostate cancer presents intrinsic resistance against conventional chemotherapies. The typically elderly patient population excludes more aggressive treatment regimens. First clinical trials evaluating immunotherapy or tyrosine-kinase-inhibitors against prostate cancer failed. In contrast, prostate cancer can be radiosensitive and external beam radiotherapy is effective in localized prostate cancer, thus providing a good rationale for the use of systemic radiopharmaceuticals in the metastatic setting. Beta-particle emitting "bone-seekers" have a long history and are effective as analgesics but do not improve survival because they are limited by red-marrow dose. Alpha emitting ²²³Radium can be used in a dose that prolongs survival but is restricted to bone-confined patients. Currently radiolabeled high-affinity ligands to the prostate-specific membrane antigen are in clinical evaluation. While radioimmunotherapy approaches were limited by the long circulation time and slow tumor-accumulation of antibodies, low molecular weight PSMA-specific ligands offer an approx. ten-fold improved tumor to red-marrow ratio in comparison to the unspecific bone-seekers. Early clinical studies demonstrate that regarding surrogate markers, such as >50% PSA reduction (60%) and radiologic response (80%), PSMA-therapy exceeds the antitumor activity of all approved or other recently tested compounds; for example, PSA-response was only observed in approx. a total of 10% of patients treated with ipilimumab, sunitinib, cabozantinib, or xofigo, respectively and in approx. 30, 40, 50% of patients treated with abiraterone, cabazitaxel, or enzalutamide. Also progression free and overall survivals of these single-arm studies appear promising when compared to historical controls. Consecutively, the first PSMA-RLT recently advanced into phase-3 (¹⁷⁷Lu-PSMA-617; VISION-trial). Future developments aim to avoid off-target radiation by ligand-optimization and to outperform the antitumor activity of beta-emitter PSMA-RLT by labeling with highly focused, high energy transferring alpha-nuclides; however the latter potentially also increasing the risk of side-effects and additional early phase studies are needed to improve treatment protocols. Academically clinical research is developing prognostic tools to improve treatment benefit by selecting the most appropriate patients in advance.

Transcriptomic and ChIP-sequence interrogation of EGFR signaling in HER2+ breast cancer cells reveals a dynamic chromatin landscape and S100 genes as targets

BACKGROUND

The Human Epidermal Growth Factor Receptor (EGFR/HER1) can be activated by several ligands including Transforming Growth Factor alpha (TGF-α) and Epidermal Growth Factor (EGF). Following ligand binding, EGFR heterodimerizes with other HER family members, such as HER2 (human epidermal growth factor receptor-2). Previously, we showed that the EGFR is upregulated in trastuzumab resistant HER2 positive (HER2+) breast cancer cells. This study is aimed to determine the downstream effects on transcription following EGFR upregulation in HER2+ breast cancer cells.

METHODS

RNA-sequence and ChIP-sequence for H3K18ac and H3K27ac (Histone H3 lysine K18 and K27 acetylation) were conducted following an Epidermal Growth Factor (EGF) treatment time course in HER2+ breast cancer cells, SKBR3. The levels of several proteins of interest were confirmed by western blot analysis. The cellular localization of proteins of interest was examined using biochemically fractionated lysates followed by western blot analysis.

RESULTS

Over the course of 24 h, EGFR stimulation resulted in the modulation of over 4000 transcripts. Moreover, our data demonstrates that EGFR/HER2 signaling regulates the epigenome, with global H3K18ac and H3K27ac oscillating as a function of time following EGF treatment. RNA-sequence data demonstrates the activation of immediate early genes (IEGs) and delayed early genes (DEGs) within 1 h of EGF treatment. More importantly, we have identified members of the S100 (S100 Calcium Binding Protein) gene family as likely direct targets of EGFR signaling as H3K18ac, H3K27ac and pol2 (RNA polymerase II) increase near the transcription start sites of some of these genes.

CONCLUSIONS

Our data suggests that S100 proteins, which act as Ca2+ sensors, could play a role in EGF induced tumor cell growth and metastasis, contribute to trastuzumab resistance and cell migration and that they are likely drug targets in HER2+ breast cancer.

Single-Cell Sequencing of iPSC-Dopamine Neurons Reconstructs Disease Progression and Identifies HDAC4 as a Regulator of Parkinson Cell Phenotypes

Induced pluripotent stem cell (iPSC)-derived dopamine neurons provide an opportunity to model Parkinson's disease (PD), but neuronal cultures are confounded by asynchronous and heterogeneous appearance of disease phenotypes in vitro. Using high-resolution, single-cell transcriptomic analyses of iPSC-derived dopamine neurons carrying the GBA-N370S PD risk variant, we identified a progressive axis of gene expression variation leading to endoplasmic reticulum stress. Pseudotime analysis of genes differentially expressed (DE) along this axis identified the transcriptional repressor histone deacetylase 4 (HDAC4) as an upstream regulator of disease progression. HDAC4 was mislocalized to the nucleus in PD iPSC-derived dopamine neurons and repressed genes early in the disease axis, leading to late deficits in protein homeostasis. Treatment of iPSC-derived dopamine neurons with HDAC4-modulating compounds upregulated genes early in the DE axis and corrected PD-related cellular phenotypes. Our study demonstrates how single-cell transcriptomics can exploit cellular heterogeneity to reveal disease mechanisms and identify therapeutic targets.