Neutrophils, a candidate biomarker and target for radiation therapy?

Harnessing the tumor microenvironment: targeted cancer therapies through modulation of epithelial-mesenchymal transition

The tumor microenvironment (TME) is integral to cancer progression, impacting metastasis and treatment response. It consists of diverse cell types, extracellular matrix components, and signaling molecules that interact to promote tumor growth and therapeutic resistance. Elucidating the intricate interactions between cancer cells and the TME is crucial in understanding cancer progression and therapeutic challenges. A critical process induced by TME signaling is the epithelial-mesenchymal transition (EMT), wherein epithelial cells acquire mesenchymal traits, which enhance their motility and invasiveness and promote metastasis and cancer progression. By targeting various components of the TME, novel investigational strategies aim to disrupt the TME's contribution to the EMT, thereby improving treatment efficacy, addressing therapeutic resistance, and offering a nuanced approach to cancer therapy. This review scrutinizes the key players in the TME and the TME's contribution to the EMT, emphasizing avenues to therapeutically disrupt the interactions between the various TME components. Moreover, the article discusses the TME's implications for resistance mechanisms and highlights the current therapeutic strategies toward TME modulation along with potential caveats.

Revealing the effect of X-ray or proton brain irradiation on systemic inflammation and leukocyte subpopulation interplay in rodents

The absolute lymphocyte count (ALC), lymphocyte-to-monocyte ratio (LMR), and neutrophil-to-lymphocyte ratio (NLR) offer convenient means to assess systemic inflammation post-cancer treatment, which influences treatment outcomes. Understanding these biomarker variations and leukocyte subpopulation interplay is crucial for optimizing radiotherapy. Herein, leukocyte subpopulations (T-CD4+, T-CD8+, B cells, NK cells, neutrophils, monocytes) during and after brain irradiation (using X-rays or protons) in tumor-free mice were used to compute ALC, LMR, and NLR, on which radiation parameter influence was assessed by principal component analysis (PCA). NLR kinetics was further examined using modeling. Leukocyte subpopulation interplays and their response to radiation parameters were examined using PCA and correlation analysis. Under X-rays, ALC and LMR decreased, with ALC recovered to baseline after irradiation, but not LMR. Both X-rays and protons increased the NLR during irradiation, recovering in protons but not X-rays. Both irradiation volume and dose rate had a pronounced effect on the NLR. Leukocyte subpopulation interplay was observed under X-rays and protons, normalizing in the proton group by day 28. Lymphopenia was observed in all lymphocyte subpopulations under X-ray irradiation but not protons. The recovery patterns varied among the subpopulations. Neutrophil counts increased during irradiation, with the recovery of protons, but not X-rays, by day 28. Interplays between NK cells and myeloid subpopulations were evident under X-rays but not protons. Importantly, no interplay was detected between myeloid cells and T/B cells, indicating that LMR and NLR variations were primarily due to independent responses to brain irradiation. A tumor-free experimental mouse model was used to study the effects of brain radiotherapy on systemic immunity. When administering fractionated irradiation with a total dose of 20 Gy using a vertical beam to either the whole brain or hemi-brain, proton irradiation had fewer adverse impacts on the immune system compared to X-rays in tumor-free rodents.

The Effect of Radiation Treatment of Solid Tumors on Neutrophil Infiltration and Function: A Systematic Review

Radiation therapy (RT) initiates a local and systemic immune response which can induce antitumor immunity and improve immunotherapy efficacy. Neutrophils are among the first immune cells that infiltrate tumors after RT and are suggested to be essential for the initial antitumor immune response. However, neutrophils in tumors are associated with poor outcomes and RT-induced neutrophil infiltration could also change the composition of the tumor microenvironment (TME) in favor of tumor progression. To improve RT efficacy for patients with cancer it is important to understand the interplay between RT and neutrophils. Here, we review the literature on how RT affects the infiltration and function of neutrophils in the TME of solid tumors, using both patients studies and preclinical murine in vivo models. In general, it was found that neutrophil levels increase and reach maximal levels in the first days after RT and can remain elevated up to 3 weeks. Most studies report an immunosuppressive role of neutrophils in the TME after RT, caused by upregulated expression of neutrophil indoleamine 2,3-dioxygenase 1 and arginase 1, as well as neutrophil extracellular trap formation. RT was also associated with increased reactive oxygen species production by neutrophils, which can both improve and inhibit antitumor immunity. In addition, multiple murine models showed improved RT efficacy when depleting neutrophils, suggesting that neutrophils have a protumor phenotype after RT. We conclude that the role of neutrophils should not be overlooked when developing RT strategies and requires further investigation in specific tumor types. In addition, neutrophils can possibly be exploited to enhance RT efficacy by combining RT with neutrophil-targeting therapies.

Nanomaterials for bone metastasis

Bone metastasis, a prevalent occurrence in primary malignant tumors, is often associated with a grim prognosis. The bone microenvironment comprises various coexisting cell types, working together in a coordinated manner. This dynamic microenvironment plays a pivotal role in the initiation and progression of bone metastases. While cancer therapies have made advancements, the available options for addressing bone metastases remain insufficient. The advent of nanotechnology has ushered in a new era for managing and preventing bone metastases because of the physicochemical and adaptable advantages of nanoplatforms. In this review, we make an introduction of the underlying mechanisms and the current clinical therapies of bone metastases, highlighting the advances of intelligent nanosystems that can stimulate vascular regeneration, promote bone regeneration, eliminate tumor cells, minimize bone damage, and expedite bone healing. The innovation surrounding bone-targeting nanoplatforms presents a fresh approach to the theranostics of bone metastases.

Exploiting innate immunity for cancer immunotherapy

Immunotherapies have revolutionized the treatment paradigms of various types of cancers. However, most of these immunomodulatory strategies focus on harnessing adaptive immunity, mainly by inhibiting immunosuppressive signaling with immune checkpoint blockade, or enhancing immunostimulatory signaling with bispecific T cell engager and chimeric antigen receptor (CAR)-T cell. Although these agents have already achieved great success, only a tiny percentage of patients could benefit from immunotherapies. Actually, immunotherapy efficacy is determined by multiple components in the tumor microenvironment beyond adaptive immunity. Cells from the innate arm of the immune system, such as macrophages, dendritic cells, myeloid-derived suppressor cells, neutrophils, natural killer cells, and unconventional T cells, also participate in cancer immune evasion and surveillance. Considering that the innate arm is the cornerstone of the antitumor immune response, utilizing innate immunity provides potential therapeutic options for cancer control. Up to now, strategies exploiting innate immunity, such as agonists of stimulator of interferon genes, CAR-macrophage or -natural killer cell therapies, metabolic regulators, and novel immune checkpoint blockade, have exhibited potent antitumor activities in preclinical and clinical studies. Here, we summarize the latest insights into the potential roles of innate cells in antitumor immunity and discuss the advances in innate arm-targeted therapeutic strategies.

The role of angiogenic growth factors in the immune microenvironment of glioma

Angiogenic growth factors (AGFs) are a class of secreted cytokines related to angiogenesis that mainly include vascular endothelial growth factors (VEGFs), stromal-derived factor-1 (SDF-1), platelet-derived growth factors (PDGFs), fibroblast growth factors (FGFs), transforming growth factor-beta (TGF-β) and angiopoietins (ANGs). Accumulating evidence indicates that the role of AGFs is not only limited to tumor angiogenesis but also participating in tumor progression by other mechanisms that go beyond their angiogenic role. AGFs were shown to be upregulated in the glioma microenvironment characterized by extensive angiogenesis and high immunosuppression. AGFs produced by tumor and stromal cells can exert an immunomodulatory role in the glioma microenvironment by interacting with immune cells. This review aims to sum up the interactions among AGFs, immune cells and cancer cells with a particular emphasis on glioma and tries to provide new perspectives for understanding the glioma immune microenvironment and in-depth explorations for anti-glioma therapy.

Effects of UHDR and Conventional Irradiation on Behavioral and Cognitive Performance and the Percentage of Ly6G+ CD45+ Cells in the Hippocampus

We assessed the effects of conventional and ultra-high dose rate (UHDR) electron irradiation on behavioral and cognitive performance one month following exposure and assessed whether these effects were associated with alterations in the number of immune cells in the hippocampus using flow cytometry. Two-month-old female and male C57BL/6J mice received whole-brain conventional or UHDR irradiation. UHDR mice were irradiated with 9 MeV electrons, delivered by the Linac-based/modified beam control. The mice were irradiated or sham-irradiated at Dartmouth, the following week shipped to OHSU, and behaviorally and cognitively tested between 27 and 41 days after exposure. Conventional- and UHDR-irradiated mice showed impaired novel object recognition. During fear learning, conventional- and UHDR-irradiated mice moved less during the inter-stimulus interval (ISI) and UHDR-irradiated mice also moved less during the baseline period (prior to the first tone). In irradiated mice, reduced activity levels were also seen in the home cage: conventional- and UHDR-irradiated mice moved less during the light period and UHDR-irradiated mice moved less during the dark period. Following behavioral and cognitive testing, infiltrating immune cells in the hippocampus were analyzed by flow cytometry. The percentage of Ly6G+ CD45+ cells in the hippocampus was lower in conventional- and UHDR-irradiated than sham-irradiated mice, suggesting that neutrophils might be particularly sensitive to radiation. The percentage of Ly6G+ CD45+ cells in the hippocampus was positively correlated with the time spent exploring the novel object in the object recognition test. Under the experimental conditions used, cognitive injury was comparable in conventional and UHDR mice. However, the percentage of CD45+ CD11b+ Ly6+ and CD45+ CD11b+ Ly6G- cells in the hippocampus cells in the hippocampus was altered in conventional- but not UHDR-irradiated mice and the reduced percentage of Ly6G+ CD45+ cells in the hippocampus might mediate some of the detrimental radiation-induced cognitive effects.

Increased SPRY1 expression activates NF-κB signaling and promotes pancreatic cancer progression by recruiting neutrophils and macrophages through CXCL12-CXCR4 axis

PURPOSE

Pancreatic ductal adenocarcinoma (PDAC) is an aggressive disease with a high mortality rate, in which about 90% of patients harbor somatic oncogenic point mutations in KRAS. SPRY family genes have been recognized as crucial negative regulators of Ras/Raf/ERK signaling. Here, we investigate the expression and role of SPRY proteins in PDAC.

METHODS

Expression of SPRY genes in human and mice PDAC was analyzed using The Cancer Genome Atlas and Gene Expression Omnibus datasets, and by immunohistochemistry analysis. Gain-of-function, loss-of-function of Spry1 and orthotopic xenograft model were adopted to investigate the function of Spry1 in mice PDAC. Bioinformatics analysis, transwell and flowcytometry analysis were used to identify the effects of SPRY1 on immune cells. Co-immunoprecipitation and K-ras4B G12V overexpression were used to identify molecular mechanism.

RESULTS

SPRY1 expression was remarkably increased in PDAC tissues and positively associated with poor prognosis of PDAC patients. SPRY1 knockdown suppressed tumor growth in mice. SPRY1 was found to promote CXCL12 expression and facilitate neutrophil and macrophage infiltration via CXCL12-CXCR4 axis. Pharmacological inhibition of CXCL12-CXCR4 largely abrogated the oncogenic functions of SPRY1 by suppressing neutrophil and macrophage infiltration. Mechanistically, SPRY1 interacted with ubiquitin carboxy-terminal hydrolase L1 to induce activation of nuclear factor κB signaling and ultimately increase CXCL12 expression. Moreover, SPRY1 transcription was dependent on KRAS mutation and was mediated by MAPK-ERK signaling.

CONCLUSION

High expression of SPRY1 can function as an oncogene in PDAC by promoting cancer-associated inflammation. Targeting SPRY1 might be an important approach for designing new strategy of tumor therapy.

The abscopal effect of immune-radiation therapy in recurrent and metastatic cervical cancer: a narrative review

Despite human papillomavirus vaccination and screening, in about 5% of cases, cervical cancer (CC) is discovered at an initial metastatic stage. Moreover, nearly one-third of patients with locally advanced CC (LACC) will have a recurrence of their disease during follow-up. At the stage of recurrent or metastatic CC, there are very few treatment options. They are considered incurable with a very poor prognosis. For many years, the standard of care was the combination of platinum-based drug and paclitaxel with the possible addition of bevacizumab. The most recent years have seen the development of the use of immune checkpoint inhibitors (ICIs) (pembrolizumab, cemiplimab and others) in patients with CC. They have shown long term responses with improved overall survival of patients in 1st line (in addition to chemotherapy) or 2nd line (as monotherapy) treatment. Another emerging drug is tisotumab vedotin, an antibody-drug conjugate targeting tissue factor. Radiation therapy (RT) often has a limited palliative indication in metastatic cancers. However, it has been observed that RT can induce tumor shrinkage both in distant metastatic tumors beyond the radiation field and in primary irradiated tumors. This is a rarely observed phenomenon, called abscopal effect, which is thought to be related to the immune system and allows a tumor response throughout the body. It would be the activation of the immune system induced by the irradiation of cancer cells that would lead to a specific type of apoptosis, the immunogenic cell death. Today, there is a growing consensus that combining RT with ICIs may boost abscopal response or cure rates for various cancers. Here we will review the potential abscopal effect of immune-radiation therapy in metastatic cervical cancer.

Cytofluorometric characterization of the myeloid compartment of irradiated mouse tumors

The use of ionizing radiation (IR) is a cornerstone for the treatment of cancer and radiotherapy (RT) is used in roughly 50% of cancer patients. It is now well established that RT exerts widespread effects on the tumor stroma, including the immune environment. Together with its deeply characterized effects on the lymphoid compartment, RT also deeply affects the myeloid cell compartment. Fluorescence-activated flow cytometry is one of the most widely used technologies in immunology, allowing the multiparametric analysis of cells on a cell-by-cell basis. Here, we provide a detailed flow cytometry protocol to analyze the myeloid cell populations of human papillomavirus (HPV)-positive TC1/Luc tumors engrafted in the oral mucosa of immunocompetent mice, and to evaluate their modulations in response to RT. The same method, with slight modifications, can be used to study the tumor myeloid cells from a variety of other mouse tumors.

The prognostic significance of tumor-associated neutrophils and circulating neutrophils in glioblastoma (WHO CNS5 classification)

BACKGROUND

Tumor-associated neutrophils (TANs) in the tumor microenvironment are prognostic biomarkers in many malignancies. However, it is unclear whether TANs can serve as a prognostic marker for clinical outcomes in patients with glioblastoma (GBM), as classified according to World Health Organization Classification of Tumors of the Central Nervous System, fifth edition (CNS5). In the present study, we analyzed correlations of TANs and peripheral blood neutrophils prior to radiotherapy with overall survival (OS) in GBM (CNS5).

METHODS

RNA-seq expression profiles of patients with newly diagnosed GBM (CNS5) were extracted from The Cancer Genome Atlas (TCGA), and The Chinese Glioma Genome Atlas (CGGA). TAN infiltration was inferred using CIBERSORTx algorithm. Neutrophil counts prior to radiotherapy in newly diagnosed GBM (CNS5) were obtained from the First Affiliated Hospital of Fujian Medical University. The prognostic value of TANs and peripheral blood neutrophils before radiotherapy was investigated using Kaplan-Meier analysis and Cox proportional hazards models. The robustness of these findings was evaluated by sensitivity analysis, and E values were calculated.

RESULTS

A total of 146 and 173 individuals with GBM (CNS5) were identified from the TCGA and CGGA cohorts, respectively. High infiltration of TANs was of prognostic of poor OS in TCGA (HR = 1.621, 95% CI: 1.004-2.619) and CGGA (HR = 1.546, 95% CI: 1.029-2.323). Levels of peripheral blood neutrophils before radiotherapy (HR = 2.073, 95% CI: 1.077-3.990) were independently associated with poor prognosis. Sensitivity analysis determined that the E-value of high TANs infiltration was 2.140 and 2.465 in the TCGA and CGGA cohorts.

CONCLUSIONS

TANs and peripheral blood neutrophil levels before radiotherapy are prognostic of poor outcomes in GBM (CNS5).

Pre-radiotherapy systemic immune inflammation index associated with overall survival in patients with advanced EGFR mutant non-small cell lung cancer receiving thoracic radiotherapy

PURPOSE

This study aimed to investigate the prognostic potential of the pre-radiotherapy systemic immune-inflammation index (SII) for the survival of advanced lung adenocarcinoma patients with epidermal growth factor receptor (EGFR) mutations, which might provide a basis for optimizing the comprehensive treatment scheme.

METHODS

A total of 111 lung adenocarcinoma patients with EGFR mutations, who received thoracic radiotherapy, were included in this retrospective study. The primary endpoint of the study was based on the overall survival (OS) of patients. The receiver operating characteristic (ROC) curve analysis was performed to determine the optimal cut-off value of each immune inflammation index. Kaplan-Meier analysis was performed for the comparison of OS. The Cox proportional-hazard model was used for the multivariate and univariate regression analyses to determine the correlations of prognostic factors with the disease.

RESULTS

SII was divided into the high SII group (≥ 620.2; 45.95%) and the low SII group (SII < 620.2; 54.05%) based on the optimal cutoff values. The median OS rates were 53.3 and 33.3 months in the low and high SII groups, respectively, showing statistically significant differences ( hazard ratio (HR) = 0.459; 95% CI 0.286-0.736; P < 0.001). The multivariate analysis showed that, after adjusting for the significant covariates, the SII values were independently associated with the improved OS of the patients (adjusted HR = 0.444; 95% CI 0.279-0.709; P = 0.001). The low NLR values were associated with the better OS of patients (HR = 0.509; 95% CI 0.326-0.792; P = 0.005) and vice versa (HR = 0.422; 95% CI 0.213-0.836; P < 0.001). The patients in the low LMR group before radiotherapy exhibited longer OS as compared to those in the high LMR group (HR = 0.497; 95% CI 0.308-0.802; P = 0.001).

CONCLUSIONS

This study showed that these inflammatory indices might have an important prognostic potential for advanced lung adenocarcinoma patients with EGFR mutations, receiving thoracic radiotherapy and might provide a basis for the individualized treatment of these patients.

Functional plasticity of neutrophils after low- or high-dose irradiation in cancer treatment - A mini review

Over the last several decades, radiotherapy has been considered the primary treatment option for a broad range of cancer types, aimed at prolonging patients' survival and slowing down tumor regression. However, therapeutic outcomes of radiotherapy remain limited, and patients suffer from relapse shortly after radiation. Neutrophils can initiate an immune response to infection by releasing cytokines and chemokines to actively combat pathogens. In tumor immune microenvironment, tumor-derived signals reprogram neutrophils and induce their heterogeneity and functional versatility to promote or inhibit tumor growth. In this review, we present an overview of the typical phenotypes of neutrophils that emerge after exposure to low- and high-dose radiation. These phenotypes hold potential for developing synergistic therapeutic strategies to inhibit immunosuppressive activity and improve the antitumor effects of neutrophils to render radiation therapy as a more effective strategy for cancer patients, through tumor microenvironment modulation.

Emerging Role of Neutrophil Extracellular Traps in Gastrointestinal Tumors: A Narrative Review

Neutrophil extracellular traps (NETs) are extracellular fibrous networks consisting of depolymerized chromatin DNA skeletons with a variety of antimicrobial proteins. They are secreted by activated neutrophils and play key roles in host defense and immune responses. Gastrointestinal (GI) malignancies are globally known for their high mortality and morbidity. Increasing research suggests that NETs contribute to the progression and metastasis of digestive tract tumors, among them gastric, colon, liver, and pancreatic cancers. This article explores the formation of NETs and reviews the role that NETs play in the gastrointestinal oncologic microenvironment, tumor proliferation and metastasis, tumor-related thrombosis, and surgical stress. At the same time, we analyze the qualitative and quantitative detection methods of NETs in recent years and found that NETs are specific markers of coronavirus disease 2019 (COVID-19). Then, we explore the possibility of NET inhibitors for the treatment of digestive tract tumor diseases to provide a new, efficient, and safe solution for the future therapy of gastrointestinal tumors.

Abscopal Response in Metastatic Melanoma: Real-World Data of a Retrospective, Multicenter Study

Objective: To evaluate the incidence of the abscopal response (AR) in patients with metastatic melanoma requiring palliative radiotherapy (RT). Patients and methods: Patients treated for metastatic melanoma between January 1998 and February 2020 in four oncology departments were screened. Patients with progression under immune checkpoint inhibitors or without ongoing systemic treatment, and requiring palliative RT were considered. The AR was defined as an objective response according to RECIST and/or iRECIST for at least one non-irradiated metastasis at distance (≥10 cm) from the irradiated lesion. Primary endpoint was the rate of AR. Secondary endpoints were overall survival (OS), progression-free survival (PFS), local control (LC) of the irradiated lesion, and toxicity as assessed by CTCAE v5. Results: Over the period considered, 118 patients were included and analyzed. Fifteen patients (12.7%) had an AR. With a median follow-up of 7.7 months (range, 0.2−242.2), median OS and PFS after RT were significantly longer in patients with an AR compared to those without: 28 vs. 6.6 months (p < 0.01) and not reached vs. 3.2 months, respectively. No grade ≥2 toxicity was reported. Patients who developed an AR were more likely to be treated with immunotherapy (93.3% vs. 55.9%, p = 0.02). In multivariate analysis, they had a higher number of irradiated metastases treated concomitantly (HR = 16.9, p < 0.01) and a higher rate of mild infections during RT (HR = 403.5, p < 0.01). Conclusions: AR in metastatic melanoma seems to be highly prognostic of overall survival, although it is a rare phenomenon. It may be promoted by multiple concomitant treatments with RT and immunotherapy and by acute inflammatory events such as infection.

Establishment and Validation of a Predictive Model for Radiation-Associated Aspiration Pneumonia in Patients with Radiation-Induced Dysphagia after Nasopharyngeal Carcinoma

Introduction

Radiotherapy for patients with head and neck cancers raises their risk of aspiration pneumonia-related death. We aimed to develop and validate a model to predict radiation-associated aspiration pneumonia (RAP) among patients with dysphagia after radiotherapy for nasopharyngeal carcinoma (NPC).

Materials and Methods

A total of 453 dysphagic patients with NPC were retrospectively recruited from Sun Yat-Sen Memorial Hospital from January 2012 to January 2018. Patients were randomly divided into training cohort (n = 302) and internal validation cohort (n = 151) at a ratio of 2 : 1. The concordance index (C-index) and calibration curve were used to evaluate the accuracy and discriminative ability of this model. Moreover, decision curve analysis was performed to evaluate the net clinical benefit. The results were externally validated in 203 dysphagic patients from the First People's Hospital of Foshan.

Results

Derived from multivariable analysis of the training cohort, four independent factors were introduced to predict RAP, including Kubota water drinking test grades, the maximum radiation dose of lymph node gross tumor volume (Dmax of the GTVnd), neutrophil count, and erythrocyte sedimentation rate (ESR). The nomogram showed favorable calibration and discrimination regarding the training cohort, with a C-index of 0.749 (95% confidence interval (CI), 0.681 to 0.817), which was confirmed by the internal validation cohort (C-index 0.743; 95% CI, 0.669 to 0.818) and the external validation cohort (C-index 0.722; 95% CI, 0.606 to 0.838).

Conclusions

Our study established and validated a simple nomogram for RAP among patients with dysphagia after radiotherapy for NPC.

Cytidine deaminase activity increases in the blood of breast cancer patients

Cytidine deaminase (CDA), an enzyme of the pyrimidine salvage pathway, deaminates cytidine, deoxycytidine and analogs, such as gemcitabine. Constitutive low levels of CDA activity have been reported in the blood of patients with hematological malignancies or suffering from gemcitabine toxicity. We previously reported that cellular CDA deficiency leads to genetic instability. We therefore hypothesized that constitutive CDA deficiency might confer a predisposition to cancer. We analyzed CDA activity and expression in blood samples from breast cancer (BC) patients with a suspected predisposition to the disease, and in healthy controls. Contrary to our hypothesis, we found that both CDA activity and mRNA levels were higher in blood samples from BC patients than in those from controls, and that this difference was not due to excess neutrophils. CDA activity levels were significantly higher in the serum samples of BC patients treated by radiotherapy (RT) than in those of untreated healthy controls, and hormone therapy in RT-treated BC patients was associated with significantly lower levels of CDA activity. A preliminary analysis of CDA activity in the serum of the very few BC patients who had undergone no treatment other than surgery suggested that the increase in CDA activity might be due to the breast cancer itself. Our findings raise important questions, which should lead to studies to elucidate the origin and significance of the increase in CDA activity in the serum of BC patients, and the impact of hormone therapy.

Roles of tumor-associated neutrophils in tumor metastasis and its clinical applications

Metastasis, a primary cause of death in patients with malignancies, is promoted by intrinsic changes in both tumor and non-malignant cells in the tumor microenvironment (TME). As major components of the TME, tumor-associated neutrophils (TANs) promote tumor progression and metastasis through communication with multiple growth factors, chemokines, inflammatory factors, and other immune cells, which together establish an immunosuppressive TME. In this review, we describe the potential mechanisms by which TANs participate in tumor metastasis based on recent experimental evidence. We have focused on drugs in chemotherapeutic regimens that target TANs, thereby providing a promising future for cancer immunotherapy.

Radiotherapy combined with immunotherapy: the dawn of cancer treatment

Radiotherapy (RT) is delivered for purposes of local control, but can also exert systemic effect on remote and non-irradiated tumor deposits, which is called abscopal effect. The view of RT as a simple local treatment has dramatically changed in recent years, and it is now widely accepted that RT can provoke a systemic immune response which gives a strong rationale for the combination of RT and immunotherapy (iRT). Nevertheless, several points remain to be addressed such as the interaction of RT and immune system, the identification of the best schedules for combination with immunotherapy (IO), the expansion of abscopal effect and the mechanism to amplify iRT. To answer these crucial questions, we roundly summarize underlying rationale showing the whole immune landscape in RT and clinical trials to attempt to identify the best schedules of iRT. In consideration of the rarity of abscopal effect, we propose that the occurrence of abscopal effect induced by radiation can be promoted to 100% in view of molecular and genetic level. Furthermore, the “radscopal effect” which refers to using low-dose radiation to reprogram the tumor microenvironment may amplify the occurrence of abscopal effect and overcome the resistance of iRT. Taken together, RT could be regarded as a trigger of systemic antitumor immune response, and with the help of IO can be used as a radical and systemic treatment and be added into current standard regimen of patients with metastatic cancer.

Role of Serum Lymphocyte-derived Biomarkers in Nonmetastatic Muscle-invasive Bladder Cancer Patients Treated with Trimodal Therapy

Background

The role of serum lymphocyte-based biomarkers, such as the neutrophil-to-lymphocyte (NLR), lymphocyte-to-monocyte (LMR), and platelet-to-lymphocyte (PLR) ratios, was previously studied in patients with muscle-invasive bladder cancer (MIBC) treated with radical cystectomy but remains underexplored in patients treated with trimodal therapy (TMT).

Objective

To analyze the impact of serum lymphocyte-based biomarkers on main oncological outcomes after TMT for MIBC.

Design, setting, and participants

A retrospective study, including 176 patients treated with TMT for nonmetastatic MIBC (cT2–4/cN0–2) between 2001 and 2017 at a tertiary academic center, was conducted.

Intervention

TMT, consisting of initial maximal transurethral resection of the bladder tumor, followed by radiotherapy with concurrent chemotherapy.

Outcome measurements and statistical analysis

Clinicopathological characteristics, serum laboratory tests, and imaging reports were collected. NLR, LMR, and PLR were calculated before and at the end of TMT. Dynamic patterns of NLR, LMR, and PLR during TMT were studied. Multivariable regression models were performed to estimate the effect of these biomarkers on complete response (CR) to TMT and survival.

Results and limitations

The median age was 75 yr (interquartile range 66–82). Staging was cT2 in 156 (89%) and cN0 in 159 (90%) patients. A pretreatment NLR (pre-NLR) of ≥4.0 was independently associated with lower CR rates (odds ratio 0.32; p = 0.013). In addition, a pre-NLR of ≥4.0 was associated with worse cancer-specific survival (hazard ratio [HR] 1.88; p = 0.032) and overall survival (OS; HR 1.61; p = 0.033) together with other factors such as hydronephrosis, Eastern Cooperative Oncology Group performance status, and cT stage 3-4a. When both pre- and post-treatment variables were considered, an increase in NLR beyond 75% during TMT (HR 1.63; p = 0.035) was associated with worse OS. This study was limited by its retrospective design.

Conclusions

A high pre-NLR value was independently associated with lower rates of CR and worse survival in MIBC patients undergoing TMT. Prospective validation is needed to implement NLR into clinical practice.

Patient summary

In this study, we reported the oncological outcomes of patients with muscle-invasive bladder cancer treated with trimodal therapy. We found that the neutrophil-to-lymphocyte ratio, a cheap and available blood-derived biomarker, was associated with response to trimodal therapy and survival outcomes.

Roles of Neutrophils in Glioma and Brain Metastases

Neutrophils, which are the most abundant circulating leukocytes in humans, are the first line of defense against bacterial and fungal infections. Recent studies have reported the role and importance of neutrophils in cancers. Glioma and brain metastases are the most common malignant tumors of the brain. The tumor microenvironment (TME) in the brain is complex and unique owing to the brain-blood barrier or brain-tumor barrier, which may prevent drug penetration and decrease the efficacy of immunotherapy. However, there are limited studies on the correlation between brain cancer and neutrophils. This review discusses the origin and functions of neutrophils. Additionally, the current knowledge on the correlation between neutrophil-to-lymphocyte ratio and prognosis of glioma and brain metastases has been summarized. Furthermore, the implications of tumor-associated neutrophil (TAN) phenotypes and the functions of TANs have been discussed. Finally, the potential effects of various treatments on TANs and the ability of neutrophils to function as a nanocarrier of drugs to the brain TME have been summarized. However, further studies are needed to elucidate the complex interactions between neutrophils, other immune cells, and brain tumor cells.

Using dynamic cell communication improves treatment strategies of breast cancer

Several insights from the clinical treatment of breast cancer patients have revealed that only a portion of patients achieve the expected curative effect after traditional targeted therapy, that surgical treatment may promote the development of cancer metastasis, and that the optimal combination of neoadjuvant chemotherapy and traditional treatment is not clear. Therefore, a more precise classification of breast cancer and selection of treatment methods should be undertaken to improve the efficacy of clinical treatment. In the clinical treatment of breast cancer, cell communication molecules are often selected as therapeutic targets. However, various cell communications are not static. Their dynamic changes are related to communicating cells, communicating molecules, and various intertwined internal and external environmental factors. Understanding the dynamic microenvironment can help us improve therapeutic efficacy and provide new ways to more accurately determine the cancer status. Therefore, this review describes multiple types of cellular communication in the breast cancer microenvironment and incorporates internal and external environmental factors as variable signaling factors in cell communication. Using dynamic and developmental concepts, we summarize the functional changes in signaling molecules and cells to aid in the diagnosis and treatment of breast cancer.

Radiotherapy and Cytokine Storm: Risk and Mechanism

Radiotherapy (RT) shows advantages as one of the most important precise therapy strategies for cancer treatment, especially high-dose hypofractionated RT which is widely used in clinical applications due to the protection of local anatomical structure and relatively mild impairment. With the increase of single dose, ranging from 2~20 Gy, and the decrease of fractionation, the question that if there is any uniform standard of dose limits for different therapeutic regimens attracts more and more attention, and the potential adverse effects of higher dose radiation have not been elucidated. In this study, the immunological adverse responses induced by radiation, especially the cytokine storm and the underlying mechanisms such as DAMPs release, pro-inflammatory cytokine secretion and cGAS-STING pathway activation, will be elucidated, which contributes to achieving optimal hypofractionated RT regimen, improving the killing of cancer cells and avoiding the severe side effects.

Pulse-dose-rate interstitial brachytherapy in anal squamous cell carcinoma: clinical outcomes and patients' health quality perception

Purpose

To examine clinical outcomes and quality of life of patients with anal squamous cell carcinoma treated with interstitial pulsed-dose-rate brachytherapy (PDR-BT) with a boost to residual tumor after external radiotherapy.

Material and methods

Medical records of patients receiving a brachytherapy boost after radiotherapy for anal squamous cell carcinoma in our Institute between 2008 and 2019 were retrospectively reviewed. After receiving pelvic irradiation ± concurrent chemotherapy, patients received PDR-BT boost to residual tumor, in order to deliver a minimal total dose of 60 Gy. Patients’ outcomes were analyzed, with primary focus on local control, sphincter preservation, morbidity, and quality of life.

Results

A total of 42 patients were identified, included 24, 13, and 5 patients with I, II, and III tumor stages, respectively. Median brachytherapy (BT) dose was 20 Gy (range, 10-30 Gy). Median dose per pulse was 42 cGy (range, 37.5-50 cGy). With median follow-up of 60.4 months (range, 5.4-127.4 months), estimated local control and colostomy-free survival rates at 5 years were both 88.7% (95% CI: 67.4-96.4%). The largest axis of residual lesion after external beam radiation therapy (EBRT) and poor tumor shrinkage were associated with more frequent relapses (p = 0.02 and p = 0.007, respectively). Out of 40 patients with more than 6 months follow-up, only one experienced severe delayed toxicity (fecal incontinence). Health quality perception was very good or good in 20 of 22 (91%) patients, according to their replies of quality-of-life surveys. A total dose ≥ 63 Gy was associated with higher number of anorectal grade 1+ toxicities (n = 1.5 vs. n = 0.61, p = 0.02).

Conclusions

In this cohort of 42 patients with mainly I and II tumor stages, PDR-BT boost allowed for local control in 88.7% of patients, with only one grade 3 anorectal toxicity.

Tumor-associated myeloid cells: diversity and therapeutic targeting

Myeloid cells in tumor tissues constitute a dynamic immune population characterized by a non-uniform phenotype and diverse functional activities. Both tumor-associated macrophages (TAMs), which are more abundantly represented, and tumor-associated neutrophils (TANs) are known to sustain tumor cell growth and invasion, support neoangiogenesis and suppress anticancer adaptive immune responses. In recent decades, several therapeutic approaches have been implemented in preclinical cancer models to neutralize the tumor-promoting roles of both TAMs and TANs. Some of the most successful strategies have now reached the clinic and are being investigated in clinical trials. In this review, we provide an overview of the recent literature on the ever-growing complexity of the biology of TAMs and TANs and the development of the most promising approaches to target these populations therapeutically in cancer patients.

Brief review on the roles of neutrophils in cancer development

Neutrophils, which are traditionally regarded as a hallmark of inflammation, are also a member of the intratumoral immune cells. The roles of neutrophils in cancer development are diverse and undefined. So far, they are known to be involved in tumor initiation and tumor cell proliferation and metastasis. They show heterogeneity in both phenotypes and functions during early versus late stage of cancer development. Because they are also associated with the clinical outcomes of various types of solid tumors, cancer treatments that target neutrophils might be highly effective. In this review, we briefly cover the latest findings on the multiple roles of neutrophils in cancer development and point out the future directions as well.

Neutrophil diversity and plasticity in tumour progression and therapy

Neutrophils play a key role in defence against infection and in the activation and regulation of innate and adaptive immunity. In cancer, tumour-associated neutrophils (TANs) have emerged as an important component of the tumour microenvironment. Here, they can exert dual functions. TANs can be part of tumour-promoting inflammation by driving angiogenesis, extracellular matrix remodelling, metastasis and immunosuppression. Conversely, neutrophils can also mediate antitumour responses by direct killing of tumour cells and by participating in cellular networks that mediate antitumour resistance. Neutrophil diversity and plasticity underlie the dual potential of TANs in the tumour microenvironment. Myeloid checkpoints as well as the tumour and tissue contexture shape neutrophil function in response to conventional therapies and immunotherapy. We surmise that neutrophils can provide tools to tailor current immunotherapy strategies and pave the way to myeloid cell-centred therapeutic strategies, which would be complementary to current approaches.

Systemic Inflammation After Radiation Predicts Locoregional Recurrence, Progression, and Mortality in Stage II-III Triple-Negative Breast Cancer

PURPOSE

Patients with triple-negative breast cancer experience high rates of recurrence after radiation, which may be facilitated by the recruitment of circulating tumor cells to proinflammatory microenvironments in the absence of lymphocytes. We hypothesized that patients with lymphopenia and elevated inflammatory hematologic markers after radiation therapy would have an increased risk of locoregional failure.

METHODS AND MATERIALS

With approval, we retrospectively studied a cohort of women treated with adjuvant radiation therapy for stage II-III triple-negative breast cancer. We analyzed the relationship between post-radiation therapy neutrophil:lymphocyte ratio (NLR) and locoregional recurrence by using Cox regression.

RESULTS

One-hundred thirty patients met inclusion criteria, and median follow-up time was 7.6 years. Patients with an NLR ≥3 had a higher rate of locoregional failure (P = .04) and lower overall survival (P = .04). After adjusting for stage (hazard ratio [HR], 5.5; P < .0001) and neoadjuvant chemotherapy (HR, 2.5; P = .0162), NLR was highly predictive of locoregional failure (HR, 1.4; P = .0009). NLR was also highly predictive of overall survival (HR, 1.3; P = .0007) after adjustment for stage and neoadjuvant chemotherapy.

CONCLUSIONS

Innate peripheral inflammation after radiation therapy for triple-negative breast cancer in an immunocompromised setting may be a novel prognostic biomarker for locoregional recurrence, progression, and survival. This finding supports preclinical studies of post-radiation therapy inflammation-mediated tumor progression. Further studies are needed to confirm this finding and develop treatment strategies.

Stereotactic ablative body radiotherapy (SABR) combined with immunotherapy (L19-IL2) versus standard of care in stage IV NSCLC patients, ImmunoSABR: a multicentre, randomised controlled open-label phase II trial

BACKGROUND

About 50% of non-small cell lung cancer (NSCLC) patients have metastatic disease at initial diagnosis, which limits their treatment options and, consequently, the 5-year survival rate (15%). Immune checkpoint inhibitors (ICI), either alone or in combination with chemotherapy, have become standard of care (SOC) for most good performance status patients. However, most patients will not obtain long-term benefit and new treatment strategies are therefore needed. We previously demonstrated clinical safety of the tumour-selective immunocytokine L19-IL2, consisting of the anti-ED-B scFv L19 antibody coupled to IL2, combined with stereotactic ablative radiotherapy (SABR).

METHODS

This investigator-initiated, multicentric, randomised controlled open-label phase II clinical trial will test the hypothesis that the combination of SABR and L19-IL2 increases progression free survival (PFS) in patients with limited metastatic NSCLC. One hundred twenty-six patients will be stratified according to their metastatic load (oligo-metastatic: ≤5 or poly-metastatic: 6 to 10) and randomised to the experimental-arm (E-arm) or the control-arm (C-arm). The C-arm will receive SOC, according to the local protocol. E-arm oligo-metastatic patients will receive SABR to all lesions followed by L19-IL2 therapy; radiotherapy for poly-metastatic patients consists of irradiation of one (symptomatic) to a maximum of 5 lesions (including ICI in both arms if this is the SOC). The accrual period will be 2.5-years, starting after the first centre is initiated and active. Primary endpoint is PFS at 1.5-years based on blinded radiological review, and secondary endpoints are overall survival, toxicity, quality of life and abscopal response. Associative biomarker studies, immune monitoring, CT-based radiomics, stool collection, iRECIST and tumour growth rate will be performed.

DISCUSSION

The combination of SABR with or without ICI and the immunocytokine L19-IL2 will be tested as 1st, 2nd or 3rd line treatment in stage IV NSCLC patients in 14 centres located in 6 countries. This bimodal and trimodal treatment approach is based on the direct cytotoxic effect of radiotherapy, the tumour selective immunocytokine L19-IL2, the abscopal effect observed distant from the irradiated metastatic site(s) and the memory effect. The first results are expected end 2023.

TRIAL REGISTRATION

ImmunoSABR Protocol Code: NL67629.068.18; EudraCT: 2018-002583-11; Clinicaltrials.gov: NCT03705403; ISRCTN ID: ISRCTN49817477; Date of registration: 03-April-2019.

Analysis of Systemic Inflammatory Factors and Survival Outcomes in Endometrial Cancer Patients Staged I-III FIGO and Treated with Postoperative External Radiotherapy

BACKGROUND

The causal link between elevated systemic inflammation biomarkers and poor survival has been demonstrated in cancer patients. However, the evidence for this correlation in endometrial cancer (EC) is too weak to influence current criteria of risk assessment. Here, we examined the role of inflammatory indicators as a tool to identify EC patients at higher risk of death in a retrospective observational study.

METHODS

A total of 155 patients surgically diagnosed with EC stage I-III FIGO 2009 and treated with postoperative External Beam Radiotherapy (EBRT) ± brachytherapy and chemotherapy according to ESMO-ESTRO-ESGO recommendation for patients at high risk of recurrence at the Gustave Roussy Institut, France, and Hospital Clínic, Spain, between 2008 and 2017 were evaluated. The impact of pre-treatment Neutrophil-to-Lymphocyte Ratio (NLR ≥ 2.2), Monocyte-to-Lymphocyte Ratio (MLR ≥ 0.18), Systemic Immune-Inflammatory Index (SII ≥ 1100) and lymphopenia (<1.0×109/L) on overall survival (OS), cancer-specific survival and progression-free survival was evaluated. Subsequently, a cohort of 142 patients within high-advanced risk groups according to ESMO-ESGO-ESTRO classification was evaluated.

RESULTS

On univariate analysis, NLR (HR = 2.2, IC 95% 1.1-4.7), SII (HR = 2.2, IC 95% 1.1-4.6), MLR (HR = 5.0, IC 95% 1.1-20.8) and lymphopenia (HR = 3.8, IC 95% 1.6-9.0) were associated with decreased OS. On multivariate analysis, NLR, MLR, SII and lymphopenia proved to be independent unfavorable prognostic factors.

CONCLUSIONS

lymphopenia and lymphocytes-related ratio are associated with poorer outcome in surgically staged I-III FIGO EC patients classified as high risk and treated with adjuvant EBRT and could be considered at cancer diagnosis. External validation in an independent cohort is required before implementation for patients' stratification.

The post-treatment neutrophil-to-lymphocyte ratio and changes in this ratio predict survival after treatment of stage III non-small-cell lung cancer with conventionally fractionated radiotherapy

Aim: To investigate the predictive potential of post-treatment neutrophil-to-lymphocyte ratio (NLR) and changes in this ratio (ΔNLR) for stage III non-small-cell lung cancer (NSCLC) patients who received conventionally fractionated radiotherapy (CFRT). Patients & methods: The data of 168 NSCLC patients treated at the Shandong Cancer Hospital were analyzed retrospectively. The relationship between progression-free survival (PFS), overall survival (OS) and post-treatment NLR and ΔNLR were analyzed using both Kaplan-Meier and Cox regression methods. Results: Kaplan-Meier survival analyses showed that post-treatment NLR and ΔNLR were associated with PFS (p < 0.001) and OS (p < 0.001) after CFRT. Multivariate analyses revealed that ΔNLR was an independent predictor of PFS (p = 0.001) and OS (p = 0.018). Post-treatment NLR can only be used as an independent predictor of PFS (p = 0.040). Conclusion: Our results demonstrated the prognostic value of the ΔNLR in predicting PFS and OS in stage III NSCLC patients undergoing CFRT. However, post-treatment NLR has predictive value only for PFS.

Bone Metastasis: Current State of Play

Bone metastasis (BM) in cancer remains a critical issue because of its associated clinical and biological complications. Moreover, BM can alter the quality of life and survival rate of cancer patients. Growing evidence suggests that bones are a fertile ground for the development of metastasis through a "vicious circle" of bone resorption/formation and tumor growth. This review aims to outline the current major issues in the diagnosis and management of BM in the most common types of osteotropic cancers and describe the mechanisms and effects of BM. First, we discuss the incidence of BM through the following questions: Are we witnessing an increase in incidence, and are we now better equipped with modern imaging techniques? Is the advent of efficient bone resorption inhibitors affecting the bigger picture of BM management? Second, we discuss the potential effects of cancer progression and well-prescribed drugs, such as multitarget tyrosine kinase inhibitors, inhibitors of the mammalian target of rapamycin, and immune checkpoint inhibitors, on BM. Finally, we examine the duality of the effects of some therapies that may help in cancer treatment but may also contribute to further BM.

Prognostic value of post-radiotherapy neutrophil-to-lymphocyte ratio in locally advanced nasopharyngeal carcinoma

PURPOSE

To explore the temporal profile of the peripheral neutrophil-to-lymphocyte ratio (NLR) in patients with locally advanced nasopharyngeal carcinoma (LANPC) and the potential prognostic value of its dynamic changes.

METHODS

Complete blood count of 112 patients from a previous phase II study were retrospectively collected at the timepoints of the initiation of induction chemotherapy (pre-IC), within 1 week before radiotherapy started (pre-RT), and within 1 week after radiotherapy finished (post-RT). Data of 103 patients were fully recorded and Cox regression analysis was used to analyze the correlations of potential risk factors with 5‑year overall survival (OS). The performance of the prognostic factor was validated in another independent cohort of 103 matched (by T and N stage) patients selected from 236 consecutive NPC patients treated with IC and concurrent chemoradiation.

RESULTS

Multivariate analysis (MVA) identified patient age >50 years old (hazard ratio [HR] = 3.4, p = 0.02), weight loss during RT >7.5% (HR = 3.2, p = 0.03), and post-RT peripheral NLR >7.05 (vs. NLR ≤7.05, HR = 2.5, p = 0.04, 5‑year OS 71.4% vs. 87.8%) as unfavorable prognostic factors for OS. There was also a non-significant trend in the MVA that patients with post-RT peripheral NLR >7.05 showed worse progression-free survival (PFS; HR = 1.9, p = 0.06, 5‑year PFS 64.1% vs. 81.8%). Post-RT NLR had a good prognostic performance in the validation cohort (concordance index = 0.73, standard error 0.10; p = 0.02, Wilcoxon test).

CONCLUSION

Post-RT NLR is an independent prognostic factor for OS in LANPC patients. The dynamic change of the routinely tested inflammatory variable could help selection of appropriate treatment options and follow-up strategies.

Systemic immune-inflammation index as a prognostic marker in patients with newly diagnosed metastatic nasopharyngeal carcinoma: a propensity score-matched study

Background

Systemic immune-inflammation index (SII) is significantly associated with poor survival in variety of cancers. However, SII has not yet been investigated in patients with newly diagnosed metastatic nasopharyngeal carcinoma (mNPC). Thus, our aim is to explore the role of SII in metastatic Nasopharyngeal Carcinoma.

Methods

Two hundred and forty-three patients with newly diagnosed mNPC were retrospectively enrolled. The Kaplan-Meier analysis and Cox regression analysis was performed to evaluate the prognostic value of SII in overall survival (OS) and progression-free survival (PFS). Heterogeneity of factors was balanced by using propensity score-matched (PSM) analysis (1:1 for high SII versus low SII).

Results

Kaplan-Meier analysis showed that patients with high SII were associated with poor median OS (18.0 vs. 36.0 m, P<0.001) and PFS (10.0 vs. 22.0 m, P<0.001) in mNPC. The Cox regression analysis suggested that high SII was a prognostic factor for OS (HR 1.75, 95% CI: 1.22–2.52, P=0.001) and PFS (HR 1.69, 95% CI: 1.22–2.35, P=0.002). PSM analysis still confirmed that SII was an independent marker for OS (HR 1.86, 95% CI: 1.22–2.83, P=0.004) and PFS (HR 1.84, 95% CI: 1.23–2.77, P=0.003).

Conclusions

SII is an independent prognostic biomarker for poor OS and PFS in patients with newly diagnosed mNPC and might be a promising tool for guiding treatment strategy decisions.

Neutrophils promote tumor resistance to radiation therapy

Nearly two-thirds of cancer patients are treated with radiation therapy (RT), often with the intent to achieve complete and permanent tumor regression (local control). RT is the primary treatment modality used to achieve local control for many malignancies, including locally advanced cervical cancer, head and neck cancer, and lung cancer. The addition of concurrent platinum-based radiosensitizing chemotherapy improves local control and patient survival. Enhanced outcomes with concurrent chemoradiotherapy may result from increased direct killing of tumor cells and effects on nontumor cell populations. Many patients treated with concurrent chemoradiotherapy exhibit a decline in neutrophil count, but the effects of neutrophils on radiation therapy are controversial. To investigate the clinical significance of neutrophils in the response to RT, we examined patient outcomes and circulating neutrophil counts in cervical cancer patients treated with definitive chemoradiation. Although pretreatment neutrophil count did not correlate with outcome, lower absolute neutrophil count after starting concurrent chemoradiotherapy was associated with higher rates of local control, metastasis-free survival, and overall survival. To define the role of neutrophils in tumor response to RT, we used genetic and pharmacological approaches to deplete neutrophils in an autochthonous mouse model of soft tissue sarcoma. Neutrophil depletion prior to image-guided focal irradiation improved tumor response to RT. Our results indicate that neutrophils promote resistance to radiation therapy. The efficacy of chemoradiotherapy may depend on the impact of treatment on peripheral neutrophil count, which has the potential to serve as an inexpensive and widely available biomarker.

Role of AHR in the control of GBM-associated myeloid cells

Glioblastoma (GBM) is an aggressive and incurable brain tumor; its malignancy has been associated with the activity of tumor infiltrating myeloid cells. Myeloid cells play important roles in the tumor control by the immune response, but also in tumor progression. Indeed, GBM exploits multiple mechanisms to recruit and modulate myeloid cells. The Aryl Hydrocarbon Receptor (AHR) is a ligand activated transcription factor implicated in the regulation of myeloid cells. In this review, we will summarize current knowledge on the AHR role in the control of myeloid cells and its impact on GBM pathogenesis.

Increased bone marrow SUVmax on 18F-FDG PET is associated with higher pelvic treatment failure in patients with cervical cancer treated by chemoradiotherapy and brachytherapy

The aim of this study was to evaluate if bone marrow (BM) SUVmax measured on pre-treatment 18F-FDG PET/CT predicts the clinical outcome of locally advanced cervical cancer (LACC). We recruited retrospectively patients with LACC who underwent staging 18F-FDG PET/CT and had baseline blood tests, then treated by chemoradiation therapy (CRT), followed by image-guided adaptive brachytherapy (IGABT). BM SUVmax was calculated and correlated to inflammatory blood markers. Tumor size and pelvic lymph node involvement were evaluated on baseline MRI. Prognostic value of SUV uptake and blood markers regarding overall survival (OS), pelvic and extra-pelvic recurrence-free survival (PRFS and EPRFS respectively) was assessed using Cox models with adjusted p-values. 116 patients with FIGO stage Ib-IVa cervical cancer, treated between 2005 and 2014, were analyzed. The median follow-up was 75.5 months. BM SUVmax was significantly correlated to tumor SUVmax. In multivariate analysis, PRFS was significantly poorer in patients with high BM SUVmax (>2.8) and neutrophilia (p < .05). Tumor size (>5 vs ≤5 cm) could predict PRFS, EPRFS and OS (p < .05). In our cohort, FIGO stage (I-II vs III-IV), pelvic lymph node involvement and tumor SUVmax (>12 vs ≤12) were not prognostic for OS or pelvic and extra-pelvic relapses. Patients with LACC and high BM SUVmax on 18F-FDG PET have worse PFRS following CRT plus IGABT. These results can be potentially explained by the pro-inflammatory role of the tumor microenvironment and G-CSF expressed by tumor cells. These data support the role of PET as a potential indicator of disease aggressiveness beyond tumor staging.

The Contribution of the Immune System in Bone Metastasis Pathogenesis

Bone metastasis is associated with significant morbidity for cancer patients and results in a reduced quality of life. The bone marrow is a fertile soil containing a complex composition of immune cells that may actually provide an immune-privileged niche for disseminated tumor cells to colonize and proliferate. In this unique immune milieu, multiple immune cells including T cells, natural killer cells, macrophages, dendritic cells, myeloid-derived suppressor cells, and neutrophils are involved in the process of bone metastasis. In this review, we will discuss the crosstalk between immune cells in bone microenvironment and their involvement with cancer cell metastasis to the bone. Furthermore, we will highlight the anti-tumoral and pro-tumoral function of each immune cell type that contributes to bone metastasis. We will end with a discussion of current therapeutic strategies aimed at sensitizing immune cells.

Tumor-Infiltrating T Cell Receptor-Beta Repertoires are Linked to the Risk of Late Chemoradiation-Induced Temporal Lobe Necrosis in Locally Advanced Nasopharyngeal Carcinoma

PURPOSE

Temporal lobe necrosis (TLN), a late complication of nasopharyngeal carcinoma (NPC) after concurrent chemoradiotherapy (CCRT), causes permanent neurologic deficits. We aimed to investigate the risk factors for the development of CCRT-induced TLN in locally advanced NPC patients.

METHODS AND MATERIALS

The incidence of CCRT-induced TLN was assessed in consecutive patients with NPC initially staged with T_3-4N_0-3M₀ receiving curative intensity modulated radiation therapy (IMRT) and cisplatin-based chemotherapy with long-term follow-up. The TLN risk was evaluated with radiation dose-volume histograms (a dosimetric risk indicator of organ injury) and the dynamics of blood circulating neutrophil-to-lymphocyte ratios (a clinical indicator of systemic inflammation) by linear and logistic regression models. High-throughput unbiased T cell receptor-beta (TCR_beta) sequencing was performed to correlate the different TCR_beta repertoires of NPC-infiltrating lymphocytes (a biological factor of the immune microenvironment) with TLN incidence.

RESULTS

In the era of modern IMRT-based CCRT, radiation doses of up to 74 Gy achieved local control rates of more than 90% in both T₃ and T₄ diseases but still induced a remarkably higher incidence of TLN in the T₄ patients (30.14%) compared with the rare incidence of TLN observed in the T₃ patients (2.78%) (P < .0001). We found that in the T₄ NPC patients, univariate and multivariate analyses showed the radiation tolerance dose-volume effect was not an absolutely independent factor influencing TLN occurrence. However, increased TLN risk was observed in association with higher pre-CCRT baseline and post-CCRT neutrophil-to-lymphocyte ratios. There was also a link between intratumoral TCR_beta repertoire subtypes and TLN incidence. Combining the inherent TCR_beta genomic susceptibility with the clinical variable neutrophil-to-lymphocyte ratio better predicted the risk of TLN for T₄ NPC patients after CCRT.

CONCLUSIONS

The associations of tumor-infiltrating lymphocyte repertoires and blood circulating neutrophil-to-lymphocyte ratios with TLN occurrence in T₄ NPC patients suggest that the immune and inflammatory milieus play roles in the late brain damage caused by CCRT. Modulated or provoked by CCRT locally and systemically, the reciprocal interactions of neutrophils and lymphocytes in the intracranial NPC-associated immune microenvironment could be a key driver of chronic TLN pathogenesis.

Tumor Shrinkage During Chemoradiation in Locally Advanced Cervical Cancer Patients: Prognostic Significance, and Impact for Image-Guided Adaptive Brachytherapy

PURPOSE

To study the prognostic value of gross tumor volume (GTV) shrinkage and its dosimetric implication in a large cohort of patients with cervical cancer receiving definitive chemoradiotherapy plus image guided adaptive brachytherapy.

METHODS AND MATERIALS

Clinical records of consecutive patients treated in our institution between February 2004 and November 2015 by concurrent chemoradiotherapy (45 Gy in 25 fractions ± lymph node boosts) followed by a magnetic resonance imaging-guided adaptive pulse-dose rate brachytherapy were included. The prognostic value of GTV and its evolution after chemoradiotherapy were examined first on initial staging magnetic resonance imaging and then at time of brachytherapy. All measures and measurement cutoffs were selected using time-dependent area under the curve for 3-year progression-free survival (PFS).

RESULTS

GTV evolution between diagnosis and the time of brachytherapy was assessed in 247 patients. After chemoradiotherapy, complete response was observed in 75 patients (28%). Optimal cutoffs were GTV = 55 cm³ at diagnosis, GTV = 7.5 cm³ at brachytherapy, and GTV reduction ≥90%. All patients with volume above or reduction below these cutoffs had significant reduced overall survival, PFS, local control, and distant metastasis control (P < .001). Patients with anemia at diagnosis had a lower tumor volume response rate (P < .001). In multivariate analysis, incorporating the International Federation of Gynecology and Obstetrics stage, N+ stage, anemia, and dosimetric parameters for image guided adaptive brachytherapy, GTV optimal volume reduction after chemoradiotherapy was independently associated with improved overall survival, PFS, local control, and distant metastasis control (P < .001).

CONCLUSIONS

These results could provide a rationale for dose de-escalation studies in brachytherapy for patients displaying optimal GTV volumetric reduction after chemoradiotherapy and may reinforce the need for dose escalation in poorly responding patients.

Neutrophil to Lymphocyte Ratio as Predictor of Treatment Response in Esophageal Squamous Cell Cancer

BACKGROUND

The aim of this study was to assess the difference (Δ) in neutrophil to lymphocyte ratio (NLR), before and after chemoradiotherapy, as a predictor of treatment response and a prognostic factor for recurrence and disease-free survival in patients with esophageal squamous cell cancer treated with chemoradiotherapy with or without surgery.

METHODS

Patients with locally advanced esophageal squamous cell cancer treated with chemoradiation with and without surgery who had a complete blood count before and after chemoradiotherapy were included. Pretreatment and posttreatment NLR were calculated by dividing the absolute neutrophil count by the absolute lymphocyte count. The ΔNLR was defined as posttreatment minus pretreatment NLR. Characteristics were evaluated for association with ΔNLR using the Wilcoxon signed rank test or the Kruskal-Wallis test. Risk of recurrence and disease-free survival were evaluated using Gray's and the log rank tests, respectively.

RESULTS

We included 217 patients. Of them, 133 patients (61.3%) received only chemoradiotherapy and 84 (38.7%) underwent surgery after chemoradiotherapy. Among the surgical patients, 43% with pathologic complete response showed significantly lower median ΔNLR than patients with residual disease (-0.03 versus 1.04, p = 0.004). High ΔNLR was a negative predictor of treatment response (odds ratio 0.77, 95% confidence interval: 0.62 to 0.9, p = 0.004). A significant association between high ΔNLR and increased risk of recurrence was also identified.

CONCLUSIONS

The ΔNLR was inversely related to pathologic complete response and associated with risk of recurrence. This simple test, in concert with other clinical tools, can help identify patients with pathologic complete response.

Anemia and neutrophil-to-lymphocyte ratio are prognostic in p16-positive oropharyngeal carcinoma treated with concurrent chemoradiation

OBJECTIVES

We investigated the prognostic value of pre-treatment hematological parameters in patients with p16-positive oropharyngeal squamous-cell carcinoma (OPSCC).

MATERIAL AND METHODS

Neutrophil count, lymphocyte count, neutrophil-to-lymphocyte ratio (NLR), and hemoglobin concentration measurement (Hb), were collected on day one of treatment. Endpoints were overall survival (OS) and progression-free survival (PFS). All patients were planned to receive concurrent chemoradiation. Staging were reviewed according to the recent AJCC 8th edition.

RESULTS

We included 167 patients in this study. In multivariate analyses, a smoking history > 30 packyears was associated with decreased OS (p = 0.009; HR, 3.4827) and PFS (p = 0.042; HR, 2.421); Hb < 12g/dL was associated with impaired OS (p = 0.007; HR, 6.527) and PFS (p = 0.014; HR, 4.092); an NLR > 5 before treatment was associated with decreased OS (p = 0.042; HR, 2.945). Hemoglobin concentration and the NLR were not correlated (p = 0.577), nor anemia and an NLR > 5 (p = 0.167). Patients with an NLR > 5 had a significantly higher rate of disease recurrence (30.8% vs. 8.4%, p = 0.0299, RR = 3.922, 95% CI 1.351-11.386).

DISCUSSION

We found hemoglobin level and the NLR to be independent prognostic factors in p16-positive OPSCC patients. This approach is to be considered for further clinical investigations, and its significance in treatment decision-making should be further explored.