Myeloid suppressor cells in cancer and autoimmunity

Integrated Bioinformatic Analysis of SARS-CoV-2 Infection Related Genes ACE2, BSG and TMPRSS2 in Aerodigestive Cancers

Background

Cancer patients are more vulnerable to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection than the general population, with lung epithelial cells or enterocytes being the main targets. However, the expressions of SARS-CoV-2 entry-related genes in aerodigestive cancers have not been fully elucidated.

Methods

In this study, the expressions of SARS-CoV-2 receptors and cofactors, including angiotensin I-converting enzyme 2 (ACE2), basigin (BSG) and transmembrane serine protease 2 (TMPRSS2), were comprehensively assessed. We compared BSG and TMPRSS2 expressions between aerodigestive cancers and matched normal tissues through Gene Expression Profiling Interactive Analysis 2 (GEPIA2). Furthermore, expressions in healthy colon tissues at different anatomical locations were explored using the Genotype-Tissue Expression (GTEx) dataset. In addition, expressions among different tumor stages and the prognostic values were detected through GEPIA2. Moreover, the correlation between gene expression and immune infiltration was explored via Tumor Immune Estimation Resource (TIMER). Finally, expressions in primary colorectal cancer (CRC), lung metastasis and liver metastasis were investigated using the Gene Expression Omnibus (GEO) dataset GSE41258.

Results

Similar to ACE2, TMPRSS2 and BSG were also highly expressed in the digestive tracts. Intriguingly, BSG/TMPRSS2 expression in adjacent normal colon tissue or lung tissue was higher than that in corresponding healthy tissue, whereas they varied not among different tumor stages and correlated not with prognosis in aerodigestive cancers. Moreover, ACE2 was expressed at higher levels in lung metastases from CRC than in normal lung tissues.

Conclusion

SARS-CoV-2 entry genes were highly expressed in CRC, and we reported for the first time higher expression of ACE2 in lung metastases from CRC than in normal lung, indicating that these patients may be more susceptible to extrapulmonary or pulmonary SARS-CoV-2 infection. Since our study is a bioinformatic analysis, further experimental evidences and clinical data are urgently needed.

Non-depleting reformation of immunosuppressive myeloid cells to broaden the application of anti-PD therapy

Traditional methods of depleting tumor-associated myeloid cells via chemotherapy can easily lead to the re-recruitment of them, eventually resulting in chemo-resistance and presenting obstacles in immunotherapy. Herein, we report a nano-educator (NE) that when loaded with all trans retinoic acid (ATRA) and anti-PD-1 antibodies (aPD-1) instructs myeloid cells to assist T cells towards revitalizing anti-PD-1 therapy. In vivo, ATRA converts myeloid-derived suppressor cells (MDSCs) into dendritic cells (DCs), which are essential for anti-PD-1 therapy, while intervening in the polarization of macrophages. Furthermore, aPD-1-armed T cells reboot anti-tumor immunity after suppression relief, which exposes tumor-specific antigens and in turn promotes the maturation of transformed DCs. The nano-platform provides shelter for vulnerable immunomodulatory agents and durable drug release to stimulate intensive immune modulation. We established three types of tumor-bearing mice models with different myeloid cell contents to show the spatiotemporal complementarity of ATRA and aPD-1. The NE re-educates the tumor's guard to assist T cells in enhanced immunotherapy, broadening the application of aPD-1 in the treatment of anti-PD-1-resistant tumors.

Myeloid-derived suppressor cells improve corneal graft survival through suppressing angiogenesis and lymphangiogenesis

Myeloid-derived suppressor cells (MDSC) are one of the major negative regulators of immune responses during many pathological conditions such as cancer and transplantation. Emerging evidence indicates that MDSC also contribute to tumor progression through their pro-angiogenic activity in addition to immunosuppressive function. However, virtually nothing is known about the role of MDSC in the regulation of neovascularization after transplantation. Here we showed that antibody-mediated depletion of MDSC in mice led to robust growth of blood and lymphatic neovessels and rapid allograft rejection after corneal penetrating keratoplasty. In contrast, adoptive transfer of ex vivo generated MDSC from cytokine-treated bone marrow cells (evMDSC) suppressed neovascularization and prolonged corneal allograft survival in an inducible nitric oxide synthase (iNOS)-dependent manner. Mechanistically, compared to naïve MDSC control, evMDSC have increased expression of an anti-angiogenic factor thrombospondin 1 (Tsp-1) and decreased expression of two critical pro-angiogenic factors, vascular endothelial growth factor A (VEGF-A), and VEGF-C. These findings demonstrate MDSC as a critical anti-angiogenic regulator during transplantation. Our study also indicates that evMDSC are a valuable candidate agent for development of novel cell therapy to improve allograft survival after transplantation.

Reviewing immunopathology characteristics of SARS-CoV-2 for cancer entwisted with SARS-CoV-2

In December 2019, the outbreak of a novel coronavirus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), infection that started in Wuhan, Hubei Province, China, has spread to all world. Based on the accumulated data and knowledge on the coronavirus infection and immunology characteristics, this review would hope to give some hints on human immune response to SARS-CoV-2 infection in cancer patients. This insight may help in designing the appropriate immune intervention for treatment and the prophylactic/therapeutic methods against cancer under current coronavirus from immunopathology characteristics of SARS-CoV-2 and cancer entwisted with it. We should achieve accurate diagnosis and treatment for cancer patients through advantages of multidisciplinary diagnosis and treatment team. It is believed that we will eventually overcome the epidemic and win in the future.

The role of myeloid-derived suppressor cells in rheumatoid arthritis: An update

Rheumatoid arthritis (RA) is an autoimmune disease that generally affects the joints. In the late stages of the disease, it can be associated with several complications. Although the exact etiology of RA is unknown, various studies have been performed to understand better the immunological mechanisms involved in the pathogenesis of RA. At the onset of the disease, various immune cells migrate to the joints and increase the recruitment of immune cells to the joints by several immunological mediators such as cytokines and chemokines. The function of specific immune cells in RA is well-established. The shift of immune responses to Th1 or Th17 is one of the most essential factors in the development of RA. Myeloid-derived suppressor cells (MDSCs), as a heterogeneous population of myeloid cells, play a regulatory role in the immune system that inhibits T cell activity through several mechanisms. Various studies have been performed on the function of these cells in RA, which in some cases have yielded conflicting results. Therefore, the purpose of this review article is to comprehensively understand the pro-inflammatory and anti-inflammatory functions of MDSCs in the pathogenesis of RA.

Regulatory B cells in cancer

Tumorigenesis proceeds through discrete steps where acquisition of genetic lesions and changes in the surrounding microenvironment combine to drive unrestricted neoplastic proliferation and metastasis. The ability of tumor-infiltrating immune cells to promote tumor growth via the provision of signals that enable tumor cell survival and proliferation as well as contribute to immune suppression is an active area of research. Recent efforts have provided us with mechanistic insights into how B cells can positively and negatively regulate immune responses. Negative regulation of immune responses in cancer can be mediated by regulatory B cells and is often a result of increased production of cytokines that can directly and indirectly affect anti-tumor immune function and cancer cell growth. Signals that lead to the expansion of regulatory B cells and the spectrum of their functional roles are not well understood and are the subject of active research by many groups. Here, we elaborate broadly on the history of regulatory B cells in cancer and summarize recent studies that have established genetic models for the study of regulatory B cell function and their potential for therapeutic intervention in the setting of solid cancers.

Identification of a Prognostic Risk Signature of Kidney Renal Clear Cell Carcinoma Based on Regulating the Immune Response Pathway Exploration

PURPOSE

To construct a survival model for predicting the prognosis of patients with kidney renal clear cell carcinoma (KIRC) based on gene expression related to immune response regulation.

MATERIALS AND METHODS

KIRC mRNA sequencing data and patient clinical data were downloaded from the TCGA database. The pathways and genes involved in the regulation of the immune response were identified from the GSEA database. A single factor Cox analysis was used to determine the association of mRNA in relation to patient prognosis (P < 0.05). The prognostic risk model was further established using the LASSO regression curve. The survival prognosis model was constructed, and the sensitivity and specificity of the model were evaluated using the ROC curve.

RESULTS

Compared with normal kidney tissues, there were 28 dysregulated mRNA expressions in KIRC tissues (P < 0.05). Univariate Cox regression analysis revealed that 12 mRNAs were related to the prognosis of patients with renal cell carcinoma. The LASSO regression curve drew a risk signature consisting of six genes: TRAF6, FYN, IKBKG, LAT2, C2, IL4, EREG, TRAF2, and IL12A. The five-year ROC area analysis (AUC) showed that the model has good sensitivity and specificity (AUC >0.712).

CONCLUSION

We constructed a risk prediction model based on the regulated immune response-related genes, which can effectively predict the survival of patients with KIRC.

Clinical characteristics, outcomes, and risk factors for mortality in hospitalized patients with COVID-19 and cancer history: a propensity score-matched study

BACKGROUND

COVID-19 has caused great concern for patients with underlying medical conditions. We aimed to determine the prognosis of patients with current or previous cancer with either a PCR-confirmed COVID-19 infection or a probable diagnosis according to chest CT scan.

METHODS

We conducted a case control study in a referral hospital on confirmed COVID-19 adult patients with and without a history of cancer from February25th to April21st, 2020. Patients were matched according to age, gender, and underlying diseases including ischemic heart disease (IHD), diabetes mellitus (DM), and hypertension (HTN). Demographic features, clinical data, comorbidities, symptoms, vital signs, laboratory findings, and chest computed tomography (CT) images have been extracted from patients' medical records. Multivariable logistic regression was used to estimate odd ratios and 95% confidence intervals of each factor of interest with outcomes.

RESULTS

Fifty-three confirmed COVID-19 patients with history of cancer were recruited and compared with 106 non-cancerous COVID-19 patients as controls. Male to female ratio was 1.33 and 45% were older than 65. Dyspnea and fever were the most common presenting symptoms in our population with 57.86 and 52.83% respectively. Moreover, dyspnea was significantly associated with an increased rate of mortality in the cancer subgroup (p = 0.013). Twenty-six patients (49%) survived among the cancer group while 89 patients (84%) survived in control (p = 0.000). in cancer group, patients with hematologic cancer had 63% mortality while patients with solid tumors had 37%. multivariate analysis model for survival prediction showed that history of cancer, impaired consciousness level, tachypnea, tachycardia, leukocytosis and thrombocytopenia were associated with an increased risk of death.

CONCLUSION

In our study, cancer increased the mortality rate and hospital stay of COVID-19 patients and this effect remains significant after adjustment of confounders. Compared to solid tumors, hematologic malignancies have been associated with worse consequences and higher mortality rate. Clinical and para-clinical indicators were not appropriate to predict death in these patients.

Cancer patient management strategy in a Cancer Center of Zhejiang, China during the COVID-19 pandemic

Background

Due to the increased risk of viral infection and the severe shortage of medical resources during the pandemic of COVID-19, most hospitals in the epidemic areas significantly reduced non-emergency admissions and services, if not closed. As a result, it has been difficult to treat cancer patients on time, which adversely affects their prognosis. To address this problem, cancer centers must develop a strategic plan to manage both inpatients and outpatients during the pandemic, provide them with the necessary treatment, and at the same time prevent the spread of the virus among patients, visitors and medical staff.

Methods

Based upon the epidemic situation in Zhejiang Province, China, the number of running non-emergency medical wards in the Zhejiang Cancer Hospital was gradually increased in a controlled manner. All staff of the hospital received COVID-19 preventive training and was provided with three different levels of protection according to the risks of their services. Only patients without a known history of SARS-CoV-2 contact were eligible to schedule an appointment. Body temperature was measured on all patients upon their arrival at the hospital. Chest CT image, blood cell counting and travel/contact history were investigated in patients with fever. Respiratory tract samples, such as sputum and throat swabs, from all patients, including those clinically suspected of SARS-CoV-2 infection, were collected for nucleic acid detection of SARS-CoV-2 before treatment.

Results

A total of 3697 inpatients and 416 outpatients seeking cancer treatment were enrolled from February 1 to April 3, 2020, in compliance with the hospital’s infection-control interventions. The clinicopathological parameters of the patients were summarized herein. 4237 samples from 4101 patients produced negative RNA testing results. Four clinically suspected patients all presented negative RNA test results and were excluded from the SARS-CoV-2 infection through follow-up retesting and monitoring. Seven patients with only N-gene positive results were retested, followed by CT scan and SARS-CoV-2 contact history investigation. All of them were finally diagnosed as non-infected patients. There was one outpatient who was confirmed positive by virus RNA test and then followed up. She might be an asymptomatic laboratory-confirmed case. During the study period, there was no SARS-CoV-2 infection among staff, patients and escorts of patients in the Zhejiang Cancer Hospital.

Conclusion

This study suggested our infection-control interventions, including viral nucleic acid test, could be used as a reliable method to screen cancer patients in the area with moderate COVID-19 prevalence. Cancer may not be a high-risk factor of SARS-CoV-2 infection.

The effect of clinical decision making for initiation of systemic anticancer treatments in response to the COVID-19 pandemic in England: a retrospective analysis

Background

Cancer services worldwide had to adapt in response to the COVID-19 pandemic to minimise risk to patients and staff. We aimed to assess the national impact of COVID-19 on the prescribing of systemic anticancer treatment in England, immediately after lockdown and after the introduction of new treatments to reduce patient risk.

Methods

We did a retrospective analysis using data from a central National Health Service England web database mandated for clinicians to register intention to start all new systemic anticancer treatments approved for use in England since 2016. We analysed the monthly number of treatment registrations in April, 2020, after the implementation of societal lockdown on March 23, 2020, and after implementation of treatment options to reduce patient risk such as oral or less immunosuppressive drugs, in May and June, 2020. We compared the number of registrations in April–June, 2020, with the mean number of registrations and SD during the previous 6 months of unaffected cancer care (September, 2019, to February, 2020). We calculated the percentage change and absolute difference in SD units for the number of registrations overall, by tumour type, and by type and line of therapy.

Findings

In April, 2020, 2969 registrations were recorded, representing 1417 fewer registrations than in the control period (monthly mean 4386; 32% reduction, absolute difference 4·2 SDs, p<0·0001). In May, 2020, total registrations increased to 3950, representing a 10% reduction compared with the control period (absolute difference 1·3 SDs, p<0·0001). In June, 2020, 5022 registrations were recorded, representing a 15% increase compared with the control period (absolute difference 1·9 SDs; p<0·0001]).

Interpretation

After the onset of the COVID-19 pandemic, there was a reduction in systemic anticancer treatment initiation in England. However, following introduction of treatment options to reduce patient risk, registrations began to increase in May, 2020, and reached higher numbers than the pre-pandemic mean in June, 2020, when other clinical and societal risk mitigation factors (such as telephone consultations, facemasks and physical distancing) are likely to have contributed. However, outcomes of providing less treatment or delaying treatment initiation, particularly for advanced cancers and neoadjuvant therapies, require continued assessment.

Funding

None.

Managing cancer patients during COVID-19 pandemic: a North African oncological center experience

Introduction

since the first spread of the novel coronavirus (COVID-19) in Morocco in March 2020, the Moroccan Health System underwent an important pressure and remarkable efforts were spent to provide efficient reactions to this emergency. Public hospitals have set adapted strategies dedicated to overcoming the overload of COVID-19 patients, and our Oncology and Hematology Center (OHC) has implemented a flexible adapted strategy aiming to reduce the burden of COVID-19. We report our single-center experience on the detailed infection control measures undertaken to minimize virus transmission.

Methods

we reviewed all patients treated at the OHC from March 2^nd to April 20^th, 2020 as measures were taken since the detection of the first COVID-19 case to ensure the protection of patients and healthcare providers, especially a screening zone for any patient entering the center. The patient's data were retrospectively collected and anonymized.

Results

we notified a significant decrease in patients' admissions during the lockdown period at the different units of our center. The screening area received a total of 5267 patients during our study period, with an average of 105 patients per day. Interestingly, no healthcare professional was infected and only 8 patients showed symptoms of fever and cough, and all of them had a negative test for COVID-19 (RT-PCR). Thus, the OHC is considered as a COVID-19 free center with zero cases among patients and healthcare providers.

Conclusion

by having a 0% rate of infection, the efficiency of our measures is proven, but efforts are still needed as we have to measure the impact of this pandemic in our cancer management.

Prostate cancer: a risk factor for COVID-19 in males?: A protocol for systematic review and meta analysis

INTRODUCTION

COVID-19 is now a global pandemic. Although there are very few studies describing the characteristics of SARS-CoV-2 infections in patients with prostate cancer, these patients are likely to be more susceptible to COVID-19 than healthy people because of their immunosuppressed state. However, there is no evidence that prostate cancer is a risk factor for COVID-19.

METHODS

We searched the Wanfang database, the China Science Journal Citation Report (VIP database), the China National Knowledge Infrastructure (CNKI), Web of Science, EMBASE, PubMed, and the Cochrane Library for studies related to the topic. We designed a standardized data extraction sheet and used Epidata software 3.1 for data extraction. In accordance with the Cochrane 5.1.0 standard, both a quality assessment and a risk assessment were carried out for the research meeting the inclusion criteria. The data were analyzed using Revman 5.3 and Stata 13.0 software.

RESULTS

The study integrated existing research findings and a meta-analysis of the data to investigate the prevalence of prostate cancer in males infected with SARS-CoV-2 and the adverse clinical outcomes in male patients with or without COVID-19.

CONCLUSION

The results of this research may provide a basis for judging if prostate cancer is a risk factor for males infected with SARS-CoV-2, and the findings can effectively help to prevent COVID-19 in patients with prostate cancer.

ETHICS AND DISSEMINATION

Ethics approval is not required for this systematic review as it will involve the collection and analysis of secondary data. The results of the review will be reported in international peer-reviewed journals PRORPERO REGISTRATION NUMBER:: CRD42020194071.

Circulating CD14+ HLA-DRlo/- monocytic cells as a biomarker for epithelial ovarian cancer progression

PROBLEM

Previous studies identified circulating CD14⁺ HLA-DR^lo/- monocytic cells as an immune suppressive subset in solid malignancies, such as prostate, renal cell carcinoma, and pancreatic cancer. Such monocytic cells have been implicated not only in tumour progression but also as a potential barrier for immunotherapy. This study examined the relationship between the frequency of circulating monocytic cells and epithelial ovarian cancer (EOC) progression pre- and post-frontline chemotherapy, defined by disease stage, which is a leading prognostic factor for this malignancy.

METHOD OF STUDY

Incident cases of 236 women with EOC were recruited and comprehensive flow cytometry was utilized to assess the frequency of peripheral blood CD33⁺ CD11b⁺ HLA-DR^-/low CD14⁺ CD15^- monocytic cells, henceforth termed CD14⁺ HLA-DR^lo/- monocytic cells, prior to and after completion of frontline chemotherapy. Multivariable odds ratios (OR) were used to estimate the association between CD14⁺ HLA-DR^lo/- monocytic cell percentages and disease stage. Wilcoxon signed-rank tests evaluated changes in these monocytic cell levels pre- and post-chemotherapy in a patient subset (n = 70).

RESULTS

Patients with elevated frequencies of circulating CD14⁺ HLA-DR^lo/- monocytic cells at diagnosis were at 3.33-fold greater odds of having advanced stage (III/IV) EOC (CI: 1.04-10.64), with a significant trend in increasing CD14⁺ HLA-DR^lo/- monocytic cell levels (P = .04). There was a 2.02% median decrease of these monocytic cells post-chemotherapy among a subset of patients with advanced stage disease (P < .0001).

CONCLUSION

These findings support the potential clinical relevance of CD14⁺ HLA-DR^lo/- monocytic cells in EOC for prognosis and may indicate a non-invasive biomarker to measure disease progression.

The Immunoregulatory Role of Myeloid-Derived Suppressor Cells in the Pathogenesis of Rheumatoid Arthritis

Myeloid-derived suppressor cells (MDSCs) are a group of cells that regulate the immune response and exert immunosuppressive effects on various immune cells. Current studies indicate that MDSCs have both anti-inflammatory effects and proinflammatory effects on rheumatoid arthritis (RA) and RA animal models. MDSCs inhibit CD4+ T cells, which secrete proinflammatory factors such as IFN-γ, IL-2, IL-6, IL-17, and TNF-α, by inhibiting iNOS, ROS, and IFN-γ and promoting the production of the anti-inflammatory factor IL-10. MDSCs can suppress dendritic cells by reducing MHC-II and CD86 expression, expand Treg cells in vitro through the action of IL-10, inhibit B cells through NO and PGE2, and promote Th17 cell responses by secreting IL-1β. As a type of osteoclast precursor cell, MDSCs can differentiate into osteoclasts through activation of the NF-κB pathway via IL-1α. Overall, our study reviews the research progress related to MDSCs in RA, focusing on the effects of MDSCs on various types of cells and aiming to provide ideas to help reveal the important role of MDSCs in RA.

Analyzing One Cell at a TIME: Analysis of Myeloid Cell Contributions in the Tumor Immune Microenvironment

Tumor-mediated regulation of the host immune system involves an intricate signaling network that results in the tumor's inherent survival benefit. Myeloid cells are central in orchestrating the mechanisms by which tumors escape immune detection and continue their proliferative programming. Myeloid cell activation has historically been classified using a dichotomous system of classical (M1-like) and alternative (M2-like) states, defining general pro- and anti-inflammatory functions, respectively. Explosions in bioinformatics analyses have rapidly expanded the definitions of myeloid cell pro- and anti-inflammatory states with different combinations of tissue- and disease-specific phenotypic and functional markers. These new definitions have allowed researchers to target specific subsets of disease-propagating myeloid cells in order to modify or arrest the natural progression of the associated disease, especially in the context of tumor-immune interactions. Here, we discuss the myeloid cell contribution to solid tumor initiation and maintenance, and strategies to reprogram their phenotypic and functional fate, thereby disabling the network that benefits tumor survival.

Clinical courses and outcomes of five patients with primary lung cancer surgically treated while affected by Severe acute respiratory syndrome coronavirus 2

OBJECTIVES

There is currently a lack of clinical data on the novel beta-coronavirus infection [caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)] and concomitant primary lung cancer. Our goal was to report our experiences with 5 patients treated for lung cancer while infected with SARS-CoV-2.

METHODS

We retrospectively evaluated 5 adult patients infected with SARS-CoV-2 who were admitted to our thoracic surgery unit between 29 January 2020 and 4 March 2020 for surgical treatment of a primary lung cancer. Clinical data and outcomes are reported.

RESULTS

All patients were men with a mean age of 74.0 years (range 67-80). Four of the 5 patients (80%) reported chronic comorbidities. Surgery comprised minimally invasive lobectomy (2 patients) and segmentectomy (1 patient), lobectomy with en bloc chest wall resection (1 patient) and pneumonectomy (1 patient). Mean chest drain duration was 12.4 days (range 8-22); mean hospital stay was 33.8 days (range 21-60). SARS-CoV-2-related symptoms were fever (3 patients), persistent cough (3 patients), diarrhoea (2 patients) and syncope (2 patients); 1 patient reported no symptoms. Morbidity related to surgery was 60%; 30-day mortality was 40%. Two patients (1 with a right pneumonectomy, 74 years old; 1 with a lobectomy with chest wall resection and reconstruction, 70 years old), developed SARS-CoV-2-related lung failure leading to death 60 and 32 days after surgery, respectively.

CONCLUSIONS

Lung cancer surgery may represent a high-risk factor for developing a severe case of coronavirus disease 2019, particularly in patients with advanced stages of lung cancer. Additional strategies are needed to reduce the risk of morbidity and mortality from SARS-CoV-2 infection during treatment for lung cancer.

Myeloid-Derived Suppressor Cells Promote the Progression of Primary Membranous Nephropathy by Enhancing Th17 Response

Several studies have confirmed that the myeloid-derived suppressor cells (MDSCs) are closely associated with autoimmune diseases, but their exact role in these processes remains largely unclear. Here, we investigated the role MDSCs in patients with primary membranous nephropathy (PMN). Compared to healthy controls (HCs), PMN patients showed significantly increased number of HLA-DR^-CD11b⁺CD33⁺ MDSCs in the peripheral blood, including both CD14⁺CD66b^- monocytic and CD14^-CD66b⁺ granulocytic MDSCs. The frequency of MDSCs was positively correlated with the level of serum anti-phospholipase A2 receptor (anti-PLA2R), 24-h urine protein quantification, and disease activity in PMN patients. Consistently, enhanced T helper 2 (Th2) and T helper 17 (Th17) immune responses were positively associated with plasma anti-PLA2R levels, 24-h urine protein quantification, and the disease activity in PMN patients. Moreover, compared to HCs, MDSCs from PMN patients exhibited significantly elevated arginase-1 (ARG-1) production and increased potential to promote Th17 differentiation in vitro in an ARG-1-dependent manner. This study directly demonstrates a pathogenic role for MDSCs in human PMN and provides a molecular mechanism for the pathogenesis of PMN. Our data show that MDSCs may promote PMN disease progression mainly by enhancing Th17 response. Therefore, MDSCs may be an important diagnostic, therapeutic, and prognostic marker for PMN diseases.

COVID-19 in cancer patients: risk, clinical features, and management

A novel coronavirus known as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has spread across the world, prompting the World Health Organization to declare the coronavirus disease of 2019 (COVID-19) a public health emergency of international concern. Cancer patients are regarded as a highly vulnerable population to SARS-CoV-2 infection and development of more severe COVID-19 symptoms, which is possibly due to the systemic immunosuppressive state caused directly by tumor growth and indirectly by effects of anticancer treatment. Currently, much effort has been directed toward studying the pathogenesis and treatment of COVID-19, but the risk profiles, prognoses, and treatment outcomes in cancer patients remain unclear. Based on the current literature, we summarize the risk profiles, clinical and biochemical characteristics, and therapy outcomes of COVID-19 infections in cancer patients. The challenges in the clinical care of cancer patients with COVID-19 are discussed. The goal of this review is to stimulate research to better understand the biological impact and prognoses of COVID-19 infections in cancer patients, thus facilitating improvement of the clinical management of these patients.

Understanding the epidemiology, pathophysiology, diagnosis and management of SARS-CoV-2

The emergence of coronavirus disease 2019 (COVID-19) in December 2019 has resulted in over 20 million cases and 741,808 deaths globally, affecting more than 200 countries. COVID-19 was declared a pandemic on 11 March 2020 by the World Health Organization. The disease is caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). There is limited information on COVID-19, and treatment has so far focused on supportive care and use of repurposed drugs. COVID-19 can be transmitted via person-to-person contact through droplet spread. Some of the recommended precautionary measures to reduce the rate of disease spread include social distancing, good hygiene practices, and avoidance of crowded areas. These measures are effective because the droplets are heavy and can only travel approximately 1 meter in the air, settling quickly on fixed surfaces. Promising strategies to combat SARS-CoV-2 include discovery of therapeutic targets/drugs and vaccines. In this review, we summarize the epidemiology, pathophysiology, and diagnosis of COVID-19. We also address the mechanisms of action of approved repurposed drugs for therapeutic management of the disease.

Good clinical practice advice for the management of patients with gynaecological cancer during the COVID-19 pandemic in Nigeria and other resource-constrained countries

The impact of the COVID-19 pandemic on healthcare services in settings with under-resourced health systems such as that of Nigeria is likely to be substantial in the coming months. The gynaecological oncology services still need to be prioritised as an essential core health service. There are increasing concerns from both physicians and patients regarding how to manage patients diagnosed with cancer during this pandemic as evidence suggests a substantial increase in the risk of COVID-19-related deaths amongst patients with cancer. However, we recognise that despite this great challenge, we must continue to provide the highest quality of care to the patients, whereas, at the same time, ensure adequate safety not only for the patients and their families but also for the entire oncology team. We advocate that due to the widespread travel restrictions and inability to refer patients for the highest level of care at this period, centres without radiotherapy facilities as seen in most resource-limited settings should always consider lower level care options such as the use of chemotherapy pending when there is a better access to these facilities. We, therefore, developed this good clinical practice advice to staff of the gynaecological oncology unit in the centre and other resource-constrained settings for the management of patients with gynaecological cancer during the COVID-19 pandemic.

Bioinformatic Analysis of Correlation between Immune Infiltration and COVID-19 in Cancer Patients

In 2020, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused infections worldwide. However, the correlation between the immune infiltration and coronavirus disease 2019 (COVID-19) susceptibility or severity in cancer patients remains to be fully elucidated. ACE2 expressions in normal tissues, cancers and cell lines were comprehensively assessed. Furthermore, we compared ACE2 expression between cancers and matched normal tissues through Gene Expression Profiling Interactive Analysis (GEPIA). In addition, we performed gene set enrichment analysis (GSEA) to investigate the related signaling pathways. Finally, the correlations between ACE2 expression and immune infiltration were investigated via Tumor Immune Estimation Resource (TIMER) and GEPIA. We found that ACE2 was predominantly expressed in both adult and fetal tissues from the digestive, urinary and male reproductive tracts; moreover, ACE2 expressions in corresponding cancers were generally higher than that in matched healthy tissues. GSEA showed that various metabolic and immune-related pathways were significantly associated with ACE2 expression across multiple cancer types. Intriguingly, we found that ACE2 expression correlated significantly with immune cell infiltration in both normal and cancer tissues, especially in the stomach and colon. These findings proposed a possible fecal-oral and maternal-fetal transmission of SARS-CoV-2 and suggested that cancers of the respiratory, digestive or urinary tracts would be more vulnerable to SARS-CoV-2 infection.

Sildenafil might impair maternal-fetal immunotolerance by suppressing myeloid-derived suppressor cells in mice

Myeloid-derived suppressor cells (MDSCs) as an important population of immune cells were found to restrain T cell function, polarize T-helper cells (Th) 1/Th2 toward Th2 response and induce regulatory T cells (Tregs), therefore enhancing the immunotolerance during pregnancy. Sildenafil has been applied for poor endometrial quality in implantation failure patients. Nevertheless, investigations have shown that sildenafil could reduce MDSCs-dependent immunosuppression. Whether sildenafil affects embryo implantation by suppressing MDSCs? To address this question, using the mice model, we investigated the amounts of immune cells in peripheral blood and endometrial cells from control group (CG), sildenafil low-dose group (LDG) and high-dose group (HDG). We found that both treatment groups displayed a marked deficiency in polymorphonuclear (PMN)-MDSCs and Th2 from mice blood and endometrium as compared to these from CG. The frequency of Tregs in endometrium from HDG was lower than those from CG. Th1/Th2 ratio in both periphery and uterus from study groups showed a significant increase as compared to those from CG. By relevance analysis, we found that the level of Tregs positively correlated with the level of PMN-MDSCs, whereas the Th1/Th2 ratio negatively correlated with the frequency of PMN-MDSCs in uterus. Moreover, there was a positive relationship between the amount of blood PMN-MDSCs and endometrial PMN-MDSCs. These results suggest that we should carefully weigh the pros and cons of using sildenafil when applied to patients with poor endometrial receptivity.

Coronavirus disease-2019 in cancer patients. A report of the first 25 cancer patients in a western country (Italy)

Background: We describe cancer patients with coronavirus disease-2019 (COVID-19) infection treated at the Piacenza's general hospital (north Italy). Materials & methods: 25 cancer patients infected by COVID-19 admitted at the Piacenza's general hospital from 21 February to 18 March 2020. Outcome from the infection were compared with infected noncancer patients. Results: 20 patients (80%) were treated with antiviral therapy and hydroxychloroquine and five (20%) received hydroxychloroquine alone. Nine (36%) patients died, while 16 (64%) overcome the infection. In the control group the mortality was 16.13% and the overcome from infection was 83.87%. Conclusion: Mortality for COVID-19 was greater in cancer patients when compared with noncancer patients, worse prognosis for older age, women and patients treated with hydroxychloroquine alone. However, the comparisons did not reach statistical significance in most cases. This could be due to the small sample size that is the main limitation of the study.

A therapeutic HPV16 E7 vaccine in combination with active anti-FGF-2 immunization synergistically elicits robust antitumor immunity in mice

FGF-2 accumulates in many tumor tissues and is closely related to the development of tumor angiogenesis and the immunosuppressive microenvironment. This study aimed to investigate whether active immunization against FGF-2 could modify antitumor immunity and enhance the efficacy of an HPV16 E7-specific therapeutic vaccine. Combined immunization targeting both FGF-2 and E7 significantly suppressed tumor growth, which was accompanied by significantly increased levels of IFN-γ-expressing splenocytes and effector CD8 T cells and decreased levels of immunosuppressive cells such as regulatory T cells (Tregs) and myeloid-derived suppressor cells(MDSCs) in both the spleen and tumor; in addition, the levels of FGF-2 and neovascularization in tumors were decreased in the mice receiving the combined immunization, and tumor cell apoptosis was promoted. The combination of an HPV16 E7-specific vaccine and active immunization against FGF-2 significantly enhances antitumor immune responses in mice with TC-1 tumors, indicating a promising strategy for tumor immunotherapy.

Notch-Inflammation Networks in Regulation of Breast Cancer Progression

Members of the Notch family and chronic inflammation were each separately demonstrated to have prominent malignancy-supporting roles in breast cancer. Recent investigations indicate that bi-directional interactions that exist between these two pathways promote the malignancy phenotype of breast tumor cells and of their tumor microenvironment. In this review article, we demonstrate the importance of Notch-inflammation interplays in malignancy by describing three key networks that act in breast cancer and their impacts on functions that contribute to disease progression: (1) Cross-talks of the Notch pathway with myeloid cells that are important players in cancer-related inflammation, focusing mainly on macrophages; (2) Cross-talks of the Notch pathway with pro-inflammatory factors, exemplified mainly by Notch interactions with interleukin 6 and its downstream pathways (STAT3); (3) Cross-talks of the Notch pathway with typical inflammatory transcription factors, primarily NF-κB. These three networks enhance tumor-promoting functions in different breast tumor subtypes and act in reciprocal manners, whereby Notch family members activate inflammatory elements and vice versa. These characteristics illustrate the fundamental roles played by Notch-inflammation interactions in elevating breast cancer progression and propose that joint targeting of both pathways together may provide more effective and less toxic treatment approaches in this disease.

A Guide for Oncologic Patient Management during Covid-19 Pandemic: The Initial Experience of an Italian Oncologic Hub with Exemplificative Focus on Uro-Oncologic Patients

The recent exponential increase in the number of COVID-19 patients in Italy led to the adoption of specific extraordinary measures, such as the need to convey treatment of all non-deferrable cancer patients to specialized centres (hubs). We reported a comprehensive summary of guidelines to create and run an oncologic hub during the COVID-19 pandemic. Oncologic hubs must fulfil some specific requirements such as a high experience in oncologic patient treatment, strict strategies applied to remain a “COVID-19-free” centre, and the creation of a dedicated multidisciplinary “hub team”. Cancer treatment of patients who belong to external centres, namely spoke centres, could be organized in different pathways according to the grade of involvement and/or availability of the medical team of the spoke centre. Moreover, dedicated areas should be created for the management and treatment of patients who developed COVID-19 symptoms after hospitalization (i.e., dedicated wards, operation rooms and intensive care beds). Lastly, hospital staff must be highly trained for both preventing COVID-19 contagion and treating patients who develop the infection. We provided a simplified, but complete and easily applicable guide. We believe that this guide could help those clinicians who have to treat oncologic patients during the COVID-19 pandemic.

ESMO management and treatment adapted recommendations in the COVID-19 era: colorectal cancer

COVID-19 pandemic challenges health system capacities in many countries. National healthcare services have to manage unexpected shortage of healthcare resources that have to be reallocated according to the principles of fair and ethical prioritisation, in order to maintain the highest levels of care to all patients, ensure the safety of patients and healthcare workers and save as many lives as possible. Beyond that, cancer care services have to pursue restructuring, following the same evidence-based dispositions. In this article, we propose guidance to the management of colorectal cancer during the pandemic, prioritised according to a three-tiered framework, based on expert clinical judgement and magnitude of benefit expected from specific interventions. Since the availability of resources for diagnostic procedures, surgery and postoperative care, systemic therapy and radiotherapy may differ, authors did separate prioritisation analyses. The impact of postponing or abrogating cancer interventions on outcomes according to a high, medium or low priority scale, is outlined and discussed. The implementation of healthcare services using telemedicine is explored: it reveals itself as functional and effective for limiting patients’ need to travel to centres and thereby has the potential to reduce diffusion of severe acute respiratory syndrome coronavirus 2. Colorectal cancer demands a considerable amount of medical resources. Therefore, the redefinition of its diagnostic and therapeutic algorithms with a rigorous method is crucial in order to ensure the highest quality of continuum of care in the broader context of the pandemic and the challenged healthcare systems.

Dual Challenge of Cancer and COVID-19: Impact on Health Care and Socioeconomic Systems in Asia Pacific

Coronavirus or COVID-19 is caused by severe acute respiratory syndrome coronavirus 2. The COVID-19 pandemic has resulted in social and economic disruption throughout the entire world. Each country is being challenged. Although much of the world's focus has been on the rapid spread in Italy, Spain, and the United States, the potential impact on the world's poor, a majority of whom are living in Asia, could be devastating. Asia has the world's most densely populated cities, and its developing countries are facing challenges in their socioeconomic and health care systems. COVID-19 is quickly overwhelming the fragile and overstretched health systems of low- and low- to middle-income countries. With its aging population having chronic diseases and the growing burden of cancer, Asia is facing the dual challenge of controlling the spread of COVID-19 and at the same time providing and maintaining cancer care.

Clinical characteristics of 9 cancer patients with SARS-CoV-2 infection

In December 2019, a cluster of pneumonia cases was caused by the Severe Acute Respiratory Syndrome coronavirus 2 (SARS-CoV-2) in Wuhan, China. Cancer patients are a special group, the immunity of them will be suppressed because of various anti-tumor treatments, and the risk of infection will be greatly increased, so we will report clinical features of 9 cancer patients with SARS-CoV-2 infection. 5 (56%) patients were ordinary type, 3 (33%) were severe type, and 1 (11%) was critical type. A total of 8 patients received combined therapy of traditional Chinese medicines and western medicines. From the clinical outcomes of these 8 patients, western combined therapy of traditional Chinese medicine was indeed an effective treatment method. D-dimmer rise, infection index rise, and chest CT(computed tomography) progression may be clinical warning indicators for severe patients, in our study, more 50% of patients had elevated levels of these indicators, but only 44% (including the dead) of patients had received treatment in the intensive care unit. 5 (56%) ordinary type patients had been discharged, while the 1 (11%) critical type patient died 3 days after admission. Cancer comorbidity seems to have no direct relationship with severe events, and the combination of traditional Chinese medicine and western medicine may be effective in the prevention and treatment of novel coronavirus-infected pneumonia (NICP).

Multidisciplinary approach to COVID-19 and cancer: consensus from scientific societies in Argentina

INTRODUCTION

The world is living through an outbreak of an acute respiratory syndrome caused by a new betacoronavirus known as coronavirus 2 (SARS CoV-2), which has been declared an international public health emergency by the World Health Organisation. Cancer patients are a very special population in this setting since they are more susceptible to viral infections than the general population. Several recommendations have been made on this issue, most of them based on expert opinion and institutional experience. It is essential to gather the evidence available for decision making.

OBJECTIVE

To review the evidence available in order to create a multi-institutional position from the perspective of scientific societies in Argentina involved in the management of cancer patients.

METHODOLOGY

The review included two phases: 1) search and systematic revision of the medical literature; 2) consensus and revision of the document drafted by national scientific societies involved in the management and care of cancer patients using the modified Delphi method. The final results were presented at a videoconference with all the participants. Also, additional comment and recommendations were discussed. The final document was revised and approved for publication by the members of the panel.

RESULTS

The consensus panel included 18 representatives from scientific societies from Argentina who assessed the evidence and then made recommendations for the management of cancer patients in our country. International guidelines (CDC; ASCO, NCCN and ESMO) were considered as a background for analysis, as well as institutional guidelines and an open ad hoc survey administered to 114 healthcare professionals from the scientific societies involved in this study.The recommendations are grouped as follows: 1) general care interventions-training of the personnel, cleaning and disinfection of the hospital premises and patient scheduling; 2) treatment decisions-patient care, surgeries, immunosuppressive therapy, radiotherapy and screening; 3) ethical considerations-optimisation of resources, end-of-life care for critically-ill patients; 4) management of hospitalised patients; and 5) wellbeing of the healthcare team.The general recommendation arising from the study is that the management of cancer patients must adapt to the exceptional pandemic status quo without disregarding treatment or cure options. Moreover, healthcare professional accompaniment of all patients should not be neglected. All healthcare professionals must make a significant joint effort to create multidisciplinary teams to discuss the most appropriate measures for each particular situation.

CONCLUSIONS

The scientific evidence available on this topic worldwide is in progress. This together with the epidemiologically shifting scenario poses unprecedented challenges in the management of cancer amidst this global pandemic. Furthermore, the key role of the healthcare structural organisation appears evident, such as the drafting of clear guidelines for all the stakeholders, adaptability to constant change and an interdisciplinary shared vision through consensus to provide adequate care to our cancer patients in the light of uncertainty and fast-paced change.

High-salt diet inhibits tumour growth in mice via regulating myeloid-derived suppressor cell differentiation

High-salt diets are associated with an elevated risk of autoimmune diseases, and immune dysregulation plays a key role in cancer development. However, the correlation between high-salt diets (HSD) and cancer development remains unclear. Here, we report that HSD increases the local concentration of sodium chloride in tumour tissue, inducing high osmotic stress that decreases both the production of cytokines required for myeloid-derived suppressor cells (MDSCs) expansion and MDSCs accumulation in the blood, spleen, and tumour. Consequently, the two major types of MDSCs change their phenotypes: monocytic-MDSCs differentiate into antitumour macrophages, and granulocytic-MDSCs adopt pro-inflammatory functions, thereby reactivating the antitumour actions of T cells. In addition, the expression of p38 mitogen-activated protein kinase-dependent nuclear factor of activated T cells 5 is enhanced in HSD-induced M-MDSC differentiation. Collectively, our study indicates that high-salt intake inhibits tumour growth in mice by activating antitumour immune surveillance through modulating the activities of MDSCs.

Do checkpoint inhibitors compromise the cancer patients' immunity and increase the vulnerability to COVID-19 infection?

The severe acute respiratory syndrome coronavirus 2 (SARS-Cov-2) has been declared a pandemic by the WHO that claimed the lives of thousands of people within a few months. Cancer patients represent a vulnerable population due to the acquired immunodeficiency associated with anti-cancer therapy. Immune checkpoint inhibitors have largely impacted the prognosis of a multitude of malignancies with significant improvement in survival outcomes and a different, tolerable toxicity profile. In this paper, we assess the safety of ICI administration in cancer patients during the coronavirus pandemic in order to guide the usage of these highly efficacious agents.

Functional activities of beta-glucans in the prevention or treatment of cervical cancer

Cervical cancer is the fourth-ranked cancer in the world and is associated with a large number of deaths annually. Chemotherapy and radiotherapy are known as the common therapeutic approaches in the treatment of cervical cancer, but because of their side effects and toxicity, researchers are trying to discovery alternative therapies. Beta-glucans, a group of glucose polymers that are derived from the cell wall of fungi, bacteria, and etc. it has been showed that beta-glucans have some anti-cancer properties which due to their impacts on adaptive and innate immunity. Along to these impacts, these molecules could be used as drug carriers. In this regard, the application of beta-glucans is a promising therapeutic option for the cancer prevention and treatment especially for cervical cancer. Herein, we have summarized the therapeutic potential of beta-glucans alone or as adjuvant therapy in the treatment of cervical cancer. Moreover, we highlighted beta-glucans as drug carriers for preventive and therapeutic purposes.

Functional activities of beta-glucans in the prevention or treatment of cervical cancer

Cervical cancer is the fourth-ranked cancer in the world and is associated with a large number of deaths annually. Chemotherapy and radiotherapy are known as the common therapeutic approaches in the treatment of cervical cancer, but because of their side effects and toxicity, researchers are trying to discovery alternative therapies. Beta-glucans, a group of glucose polymers that are derived from the cell wall of fungi, bacteria, and etc. it has been showed that beta-glucans have some anti-cancer properties which due to their impacts on adaptive and innate immunity. Along to these impacts, these molecules could be used as drug carriers. In this regard, the application of beta-glucans is a promising therapeutic option for the cancer prevention and treatment especially for cervical cancer. Herein, we have summarized the therapeutic potential of beta-glucans alone or as adjuvant therapy in the treatment of cervical cancer. Moreover, we highlighted beta-glucans as drug carriers for preventive and therapeutic purposes.

Combining Immune Checkpoint Inhibitors with Anti-Angiogenic Agents

Immunotherapy has recently emerged as a novel strategy for treating different types of solid tumors, with promising results. However, still a large fraction of patients do not primarily respond to such approaches, and even responders sooner or later develop resistance. Moreover, immunotherapy is a promising strategy for certain malignancies but not for others, with this discrepancy having been attributed to a more immunogenic microenvironment of some tumors. As abnormal and augmented tumor vessels often occur in cancerogenesis, anti-angiogenic drugs have already demonstrated their effectiveness both in preclinical and in clinical settings. By targeting abnormal formation of tumor vessels, anti-angiogenetic agents potentially result in an enhanced infiltration of immune effector cells. Moreover, crosstalks downstream of the immune checkpoint axis and vascular endothelial growth factor receptor (VEGFR) signaling may result in synergistic effects of combined treatment in tumor cells. In this review, we will describe and discuss the biological rationale of a combined therapy, underlying the modification in tumor microenvironment as well as in tumor cells after exposure to checkpoint inhibitors and anti-angiogenic drugs. Moreover, we will highlight this strategy as a possible way for overcoming drug resistance. By first discussing potential prognostic and predictive factors for combined treatment, we will then turn to clinical settings, focusing on clinical trials where this strategy is currently being investigated.

Immune Dysregulation and Recurring Mutations in Myelodysplastic Syndromes Pathogenesis

Myelodysplastic syndromes (MDS) are clonal stem cell malignancies characterized by ineffective hematopoiesis leading to peripheral cytopenias and variable risk of progression to acute myeloid leukemia. Inflammation is associated with MDS pathogenesis. Several cytokines, reactive species of oxygen/nitrogen and growth factors are directly or indirectly involved in dysfunction of the MDS bone marrow (BM) microenvironment. Mutations in genes mainly regulating RNA splicing, DNA methylation and chromatin accessibility, transcription factors, signal transduction and the response to DNA damage contribute to ineffective hematopoiesis, genomic instability and MDS development. The inflammation-associated DNA damage in hematopoietic stem cells may also contribute to MDS development and progression with aggressive clinical characteristics. Many studies have aimed at clarifying mechanisms involved in the activity of immature myeloid cells as powerful modulators of the immune response and their correlation with aging, autoimmunity, and development of cancer. In this review, we explore recent advances and accumulating evidence uniting immune dysregulation, inflammaging and recurring mutations in the pathogenesis of MDS.

Role of telomerase in the tumour microenvironment

Telomeres are specialized genomic structures that protect chromosomal ends to maintain genomic stability. Telomeric length is primarily regulated by the telomerase complex, essentially consisting of an RNA template (TERC), an enzymatic subunit (telomerase reverse transcriptase, TERT). In humans, telomerase activity is repressed during embryonic differentiation and is absent in most somatic cells. However, it is upregulated or reactivated in 80%-90% of the primary tumours in humans. The human TERT (hTERT) plays a pivotal role in cellular immortality and tumourigenesis. However, the molecular mechanisms of telomerase functioning in cancer have not been fully understood beyond the telomere maintenance. Several research groups, including ours, have demonstrated that hTERT possesses vital functions independent of its telomere maintenance, including angiogenesis, inflammation, cancer cell stemness, and epithelial-mesenchymal transformation (EMT). All these telomere-independent activities of hTERT may contribute to the regulation of the dynamics and homeostasis of the tumour microenvironment (TME), thereby promoting tumour growth and development. Cancer progression and metastasis largely depend upon the interactions between cancer cells and their microenvironment. In this review, the involvement of TERT in the tumour microenvironment and the underlying implications in cancer therapeutics have been summarized.

Increased Adiposity Enhances the Accumulation of MDSCs in the Tumor Microenvironment and Adipose Tissue of Pancreatic Tumor-Bearing Mice and in Immune Organs of Tumor-Free Hosts

Obesity is associated with increased risk and reduced survival for many types of cancer. Increasing adiposity may affect the balance between immunosuppressive and antitumor mechanisms critical for dictating cancer progression or remission. The goal of the current study was to determine if increased adiposity altered tumor growth, survival, and myeloid-derived suppressor cell (MDSC) accumulation in a subcutaneous murine model of pancreatic cancer. C57BL/6 mice were placed on a 30% kcal calorie-restricted diet, 10% kcal from fat diet fed ad libitum, or 60% kcal from fat diet fed ad libitum for 16 weeks to generate lean, overweight, and obese mice, respectively; followed by subcutaneous injection with 1 × 10⁶ Panc.02 cells. We observed a significant linear relationship between increased adiposity and increased tumor growth and mortality; increased accumulation of Gr-1⁺CD11b⁺ MDSCs; and reduced CD8 T cell:MDSC ratio in multiple tissues, including tumor. Increased adiposity also increased the accumulation of MDSCs in the spleen and lymph node of tumor-free mice. These data suggest adiposity induces MDSC accumulation, which may contribute to an immunosuppressive environment promoting tumor growth. Overall, our findings provide a rationale to prevent or reverse increased body weight as a strategy to reduce the accumulation of immunosuppressive cell types.

Inflammatory bone marrow microenvironment

Self-renewing hematopoietic stem cells and their progeny, lineage-specific downstream progenitors, maintain steady-state hematopoiesis in the bone marrow (BM). Accumulating evidence over the last few years indicates that not only primitive hematopoietic stem and progenitor cells (HSPCs), but also cells defining the microenvironment of the BM (BM niche), sense hematopoietic stress signals. They respond by directing and orchestrating hematopoiesis via not only cell-intrinsic but also cell-extrinsic mechanisms. Inflammation has many beneficial roles by activating the immune system in tissue repair and as a defense mechanism. However, chronic inflammation can have detrimental effects by stressing HSPCs, leading to cell (DNA) damage resulting in BM failure or even to leukemia. Emerging data have demonstrated that the BM microenvironment plays a significant role in the pathogenesis of hematopoietic malignancies, in particular, through disrupted inflammatory signaling, specifically in niche (microenvironmental) cells. Clonal selection in the context of microenvironmental alterations can occur in the context of toxic insults (eg, chemotherapy), not only aging but also inflammation. In this review, we summarize mechanisms that lead to an inflammatory BM microenvironment and discuss how this affects normal hematopoiesis. We pay particular attention to the process of aging, which is known to involve low-grade inflammation and is also associated with age-related clonal hematopoiesis and potentially malignant transformation.

Mitochondrial Dysfunction Pathway Networks and Mitochondrial Dynamics in the Pathogenesis of Pituitary Adenomas

Mitochondrion is a multi-functional organelle, which is associated with various signaling pathway networks, including energy metabolism, oxidative stress, cell apoptosis, cell cycles, autophagy, and immunity process. Mitochondrial proteins have been discovered to modulate these signaling pathway networks, and multiple biological behaviors to adapt to various internal environments or signaling events of human pathogenesis. Accordingly, mitochondrial dysfunction that alters the bioenergetic and biosynthetic state might contribute to multiple diseases, including cell transformation and tumor. Multiomics studies have revealed that mitochondrial dysfunction, oxidative stress, and cell cycle dysregulation signaling pathways operate in human pituitary adenomas, which suggest mitochondria play critical roles in pituitary adenomas. Some drugs targeting mitochondria are found as a therapeutic strategy for pituitary adenomas, including melatonin, melatonin inhibitors, temozolomide, pyrimethamine, 18 beta-glycyrrhetinic acid, gossypol acetate, Yougui pill, T-2 toxin, grifolic acid, cyclosporine A, dopamine agonists, and paeoniflorin. This article reviews the latest experimental evidence and potential biological roles of mitochondrial dysfunction and mitochondrial dynamics in pituitary adenoma progression, potential molecular mechanisms between mitochondria and pituitary adenoma progression, and current status and perspectives of mitochondria-based biomarkers and targeted drugs for effective management of pituitary adenomas.

Tumor-Infiltrating Immunosuppressive Cells in Cancer-Cell Plasticity, Tumor Progression and Therapy Response

In most tumors, cancer cells show the ability to dynamically transit from a non-cancer stem-like cell to a cancer stem-like cell (CSC) state and vice versa. This cell plasticity has been associated with the epithelial-to-mesenchymal transition program (EMT) and can be regulated by tumor cell-intrinsic mechanisms and complex interactions with various tumor microenvironment (TME) components. These interactions favor the generation of a specific "CSC niche" that helps maintain the main properties, phenotypic plasticity and metastatic potential of this subset of tumor cells. For this reason, TME has been recognized as an important promoter of tumor progression and therapy resistance. Tumors have evolved a network of immunosuppressive mechanisms that limits the cytotoxic T cell response to cancer cells. Some key players in this network are tumor-associated macrophages, myeloid-derived suppressor cells and regulatory T cells, which not only favor a pro-tumoral and immunosuppressive environment that supports tumor growth and immune evasion, but also negatively influences immunotherapy. Here, we review the relevance of cytokines and growth factors provided by immunosuppressive immune cells in regulating cancer-cell plasticity. We also discuss how cancer cells remodel their own niche to promote proliferation, stemness and EMT, and escape immune surveillance. A better understanding of CSC-TME crosstalk signaling will enable the development of effective targeted or immune therapies that block tumor growth and metastasis.

The promise of combining cancer vaccine and checkpoint blockade for treating HPV-related cancer

Human papillomavirus (HPV)-associated intraepithelial neoplasia or cancers are ideal candidates for cancer immunotherapy since HPV oncoproteins, such as E6 and E7 proteins of high-risk HPVs, could be utilized as foreign antigens. In HPV-associated cancers as well as nonviral cancers, the cancer cells may evade host immunity through the expression of immune checkpoint molecules, downregulation of human leukocyte antigen, and activation of immune regulatory cells. Because of these immune suppressive mechanisms, HPV therapeutic vaccines have shown little efficacy against HPV-associated cancers, although they have shown efficacy in treating HPV-associated intraepithelial neoplasias. Recently, checkpoint blockade emerged as a promising new treatment for solid cancers; however, these therapies have shown only modest efficacy against HPV-associated cancers. Here we reviewed literature analyzing a combinatory therapy using an immune checkpoint inhibitor and an HPV therapeutic vaccine for treating HPV-associated cancers to compensate for shortfalls of each monotherapy. Complimentary modes of T cell activation would be deployed; as vaccines would directly stimulate the T cells, while checkpoint inhibitors would do so by releasing inhibition. Some promising studies using animal models and early human clinical trials raised a possibility that such combinations may be efficacious in regressing HPV-associated cancers. Epitope spreading (the phenomenon in which non-targeted antigens become new targets of immune response) may play a critical role mechanistically. Currently ongoing studies will shed light as to whether such combination therapy would indeed be a promising new treatment paradigm. Current and future studies must also determine the adverse effect profile of such a combination treatment.

Myelopoiesis, metabolism and therapy: a crucial crossroads in cancer progression

Cancers promote immunological stresses that induce alterations of the myelopoietic output, defined as emergency myelopoiesis, which lead to the generation of different myeloid populations endowed with tumor-promoting activities. New evidence indicates that acquisition of this tumor-promoting phenotype by myeloid cells is the result of a multistep process, encompassing initial events originating into the bone marrow and later steps operating in the tumor microenvironment. The careful characterization of these sequential mechanisms is likely to offer new potential therapeutic opportunities. Here, we describe relevant mechanisms of myeloid cells reprogramming that instate immune dysfunctions and limit effective responses to anticancer therapy and discuss the influence that metabolic events, as well as chemotherapy, elicit on such events.