The Peripheral and Intratumoral Immune Cell Landscape in Cancer Patients: A Proxy for Tumor Biology and a Tool for Outcome Prediction

Targeting Dectin-1 and or VISTA enhances anti-tumor immunity in melanoma but not colorectal cancer model

PURPOSE

Acquired resistance to immune checkpoint blockers (ICBs) is a major barrier in cancer treatment, emphasizing the need for innovative strategies. Dectin-1 (gene Clec7a) is a C-type lectin receptor best known for its ability to recognize β-glucan-rich structures in fungal cell walls. While Dectin-1 is expressed in myeloid cells and tumor cells, its significance in cancer remains the subject of controversy.

METHODS

Using Celc7a-/- mice and curdlan administration to stimulate Dectin-1 signaling, we explored its impact. VISTA KO mice were employed to assess VISTA's role, and bulk RNAseq analyzed curdlan effects on neutrophils.

RESULTS

Our findings reveal myeloid cells as primary Dectin-1 expressing cells in the tumor microenvironment (TME), displaying an activated phenotype. Strong Dectin-1 co-expression/co-localization with VISTA and PD-L1 in TME myeloid cells was observed. While Dectin-1 deletion lacked protective effects, curdlan stimulation significantly curtailed B16-F10 tumor progression. RNAseq and pathway analyses supported curdlan's role in triggering a cascade of events leading to increased production of pro-inflammatory mediators, potentially resulting in the recruitment and activation of immune cells. Moreover, we identified a heterogeneous subset of Dectin-1+ effector T cells in the TME. Similar to mice, human myeloid cells are the prominent cells expressing Dectin-1 in cancer patients.

CONCLUSION

Our study proposes Dectin-1 as a potential adjunctive target with ICBs, orchestrating a comprehensive engagement of innate and adaptive immune responses in melanoma. This innovative approach holds promise for overcoming acquired resistance to ICBs in cancer treatment, offering avenues for further exploration and development.

Final outcomes analysis of the cell product SQZ-PBMC-HPV Phase 1 trial in incurable HPV16+ solid tumors shows improved overall survival in patients with increased CD8+ T cell tumor infiltration

Cancer vaccines strive to induce robust, antigen-targeted, T-cell-mediated immune responses but have struggled to produce meaningful regression in solid tumors. An autologous cell vaccine, SQZ-PBMC-HPV, was developed by SQZ Biotechnologies using microfluidic squeezing technology to load PBMCs with HPV16 E6 and E7 antigens in HLA-A*02+ patients. The SQZ-PBMC-HPV-101 Phase 1 trial (NCT04084951) enrolled patients with incurable HPV16+ cancers. Here, we present a post hoc analysis of the relationship between Posttreatment CD8+ T cell infiltration and patient outcomes. SQZ-PBMC-HPV was administered as monotherapy every 3 weeks. Tumor samples were collected pre-dose and post-dose 4 weeks after treatment start. Biomarkers including CD8, MHC-I, E6, E7, GZMB, and Ki67 were evaluated by immunohistochemistry, immunofluorescence, and RNA in situ hybridization, and were correlated with clinical response, survival, and drug product composition. Eighteen patients had paired pre- and post-dose biopsies. Six (33%) had an increase in CD8+ T cell density in tumor parenchyma between screening and C2D8. Patients with increased CD8+ T cell density had improved disease control rate (66.7% vs 16.7%) and median overall survival (606.5 days vs 170.0 days, p = 0.0078). Drug product was significantly enriched for higher T cells and lower monocytes in the increased CD8+ T cell density group. In patients with incurable HPV16+ solid tumors treated with SQZ-PBMC-HPV, an increase in CD8+ T cell density within the tumor parenchyma was associated with superior disease control rate and overall survival. The product composition for patients with increased CD8+ T cell density was enriched for T cells.

Exploring immune status in peripheral blood and tumor tissue in association with survival in patients with multi-organ metastatic colorectal cancer

Colorectal cancer (CRC) raises considerable clinical challenges, including a high mortality rate once the tumor spreads to distant sites. At this advanced stage, more accurate prediction of prognosis and treatment outcome is urgently needed. The role of cancer immunity in metastatic CRC (mCRC) is poorly understood. Here, we explore cellular immune cell status in patients with multi-organ mCRC. We analyzed T cell infiltration in primary tumor sections, surveyed the lymphocytic landscape of liver metastases, and assessed circulating mononuclear immune cells. Besides asking whether immune cells are associated with survival at this stage of the disease, we investigated correlations between the different tissue types; as this could indicate a dominant immune phenotype. Taken together, our analyses corroborate previous observations that higher levels of CD8+ T lymphocytes link to better survival outcomes. Our findings therefore extend evidence from earlier stages of CRC to indicate an important role for cancer immunity in disease control even after metastatic spreading to multiple organs. This finding may help to improve predicting outcome of patients with mCRC and suggests a future role for immunotherapeutic strategies.

Blood immune cells as potential biomarkers predicting relapse-free survival of stage III/IV resected melanoma patients treated with peptide-based vaccination and interferon-alpha

Introduction

Despite the recent approval of several therapies in the adjuvant setting of melanoma, tumor relapse still occurs in a significant number of completely resected stage III-IV patients. In this context, the use of cancer vaccines is still relevant and may increase the response to immune checkpoint inhibitors. We previously demonstrated safety, immunogenicity and preliminary evidence of clinical efficacy in stage III/IV resected melanoma patients subjected to a combination therapy based on peptide vaccination together with intermittent low-dose interferon-α2b, with or without dacarbazine preconditioning (https://www.clinicaltrialsregister.eu/ctr-search/search, identifier: 2008-008211-26). In this setting, we then focused on pre-treatment patient immune status to highlight possible factors associated with clinical outcome.

Methods

Multiparametric flow cytometry was used to identify baseline immune profiles in patients' peripheral blood mononuclear cells and correlation with the patient clinical outcome. Receiver operating characteristic curve, Kaplan-Meier survival and principal component analyses were used to evaluate the predictive power of the identified markers.

Results

We identified 12 different circulating T and NK cell subsets with significant (p ≤ 0.05) differential baseline levels in patients who later relapsed with respect to patients who remained free of disease. All 12 parameters showed a good prognostic accuracy (AUC>0.7, p ≤ 0.05) and 11 of them significantly predicted the relapse-free survival. Remarkably, 3 classifiers also predicted the overall survival. Focusing on immune cell subsets that can be analyzed through simple surface staining, three subsets were identified, namely regulatory T cells, CD56^dimCD16^- NK cells and central memory γδ T cells. Each subset showed an AUC>0.8 and principal component analysis significantly grouped relapsing and non-relapsing patients (p=0.034). These three subsets were used to calculate a combination score that was able to perfectly distinguish relapsing and non-relapsing patients (AUC=1; p=0). Noticeably, patients with a combined score ≥2 demonstrated a strong advantage in both relapse-free (p=0.002) and overall (p=0.011) survival as compared to patients with a score <2.

Discussion

Predictive markers may be used to guide patient selection for personalized therapies and/or improve follow-up strategies. This study provides preliminary evidence on the identification of peripheral blood immune biomarkers potentially capable of predicting the clinical response to combined vaccine-based adjuvant therapies in melanoma.

The potential of using blood circular RNA as liquid biopsy biomarker for human diseases

Circular RNA (circRNA) is a novel class of single-stranded RNAs with a closed loop structure. The majority of circRNAs are formed by a back-splicing process in pre-mRNA splicing. Their expression is dynamically regulated and shows spatiotemporal patterns among cell types, tissues and developmental stages. CircRNAs have important biological functions in many physiological processes, and their aberrant expression is implicated in many human diseases. Due to their high stability, circRNAs are becoming promising biomarkers in many human diseases, such as cardiovascular diseases, autoimmune diseases and human cancers. In this review, we focus on the translational potential of using human blood circRNAs as liquid biopsy biomarkers for human diseases. We highlight their abundant expression, essential biological functions and significant correlations to human diseases in various components of peripheral blood, including whole blood, blood cells and extracellular vesicles. In addition, we summarize the current knowledge of blood circRNA biomarkers for disease diagnosis or prognosis.

Are Circulating Immune Cells a Determinant of Pancreatic Cancer Risk? A Prospective Study Using Epigenetic Cell Count Measures

BACKGROUND

Evidence is accumulating that immune cells play a prominent role in pancreatic cancer etiology but prospective investigations are missing.

METHODS

We conducted a nested case-control study within the European Prospective Investigation into Cancer and Nutrition (EPIC) study with 502 pairs of incident pancreatic cancer cases and matched controls. Relative counts of circulating immune cells (neutrophils and lymphocyte sublineages: total CD3+, CD8+, CD4+, and FOXP3+ regulatory T cells (Tregs) relative to nucleated cells, (white blood cells) were measured by qRT-PCR. ORs with 95% confidence intervals were estimated using logistic regressions, modeling relative counts of immune cells on a continuous scale.

RESULTS

Neither relative counts of immune cell types taken individually, nor mutually adjusted for each other were associated with pancreatic cancer risks. However, in subgroup analyses by strata of lag-time, higher relative counts of Tregs and lower relative counts of CD8+ were significantly associated with an increased pancreatic cancer risks in participants diagnosed within the first 5 years of follow-up.

CONCLUSIONS

These results might reflect reverse causation, due to higher relative counts of Tregs and lower counts of CD8+ cells among individuals with more advanced stages of latent pancreatic cancer, who are closer to the point of developing clinical manifest disease.

IMPACT

We have shown, for the first time, that increased relative counts of regulatory T cells and lower relative counts of CD8+, cytotoxic T cells may be associated with pancreatic cancer risk or relatively late-stage tumor development.See related commentary by Michaud and Kelsey, p. 2176.

Can Systemic Immune-Inflammation Index Create a New Perspective for the IMDC Scoring System in Patients with Metastatic Renal Cell Carcinoma?

INTRODUCTION

The aim of the study was to evaluate impact of the systemic immune-inflammation index (SII) on prognosis and survival within the International Metastatic Renal Cell Carcinoma Database Consortium (IMDC) score groups.

METHODS

The records of 187 patients with metastatic renal cell carcinoma (RCC) were reviewed retrospectively. The SII was calculated as follows: SII = Neutrophil × Platelet/Lymphocyte. The patients were categorized into 2 groups based on a median SII of 730 (×109 per 1 L) as SII low (<730) and SII high (≥730). The Kaplan-Meier method was used for survival analysis and a Cox regression model was utilized to determine independent predictors of survival.

RESULTS

The median age was 61 years (range: 34-86 years). Kaplan-Meier tests revealed significant differences in survival between the SII-low and SII-high levels (27.0 vs. 12.0 months, respectively, p < 0.001). The Cox regression model revealed that SII was an independent prognostic factor. The implementation of the log-rank test in the IMDC groups according to the SII level provided the distinction of survival in the favorable group (SII low 49.0 months vs. SII high 11.0 months, p < 0.001), in the intermediate group (SII low 26.0 vs. SII high 15.0 months, p = 0.007), and in the poor group (SII low 19.0 vs. SII high 6.0 months, p = 0.019).

CONCLUSION

The SII was an independent prognostic factor and provided significant differences in survival for the favorable, intermediate, and poor IMDC groups. Thus, the SII added to the IMDC score may be clinically beneficial in predicting survival.

PD-1/PD-L1 checkpoint inhibitors in combination with olaparib display antitumor activity in ovarian cancer patient-derived three-dimensional spheroid cultures

Immune checkpoint inhibitors (ICIs) that target programmed cell death protein 1 (PD-1) and programmed death-ligand 1 (PD-L1) have shown modest activity as monotherapies for the treatment of ovarian cancer (OC). The rationale for using these therapies in combination with poly (ADP-ribose) polymerase inhibitors (PARP-Is) has been described, and their in vivo application will benefit from ex vivo platforms that aid in the prediction of patient response or resistance to therapy. This study examined the effectiveness of detecting patient-specific immune-related activity in OC using three-dimensional (3D) spheroids. Immune-related cell composition and PD-1/PD-L1 expression status were evaluated using cells dissociated from fresh OC tissue from two patients prior to and following 3D culture. The patient sample with the greatest increase in the proportion of PD-L1 + cells also possessed more activated cytotoxic T cells and mature DCs compared to the other patient sample. Upon cytokine stimulation, patient samples demonstrated increases in cytotoxic T cell activation and DC major histocompatibility complex (MHC) class-II expression. Pembrolizumab increased cytokine secretion, enhanced olaparib cytotoxicity, and reduced spheroid viability in a T cell-dependent manner. Furthermore, durvalumab and olaparib combination treatment increased cell death in a synergistic manner. This work demonstrates that immune cell activity and functional modulation can be accurately detected using our ex vivo 3D spheroid platform, and it presents evidence for their utility to demonstrate sensitivity to ICIs alone or in combination with PARP-Is in a preclinical setting.

The Periphery of Salivary Gland Carcinoma Tumors Reveals a PD-L1/PD-1 Biomarker Niche for the Evaluation of Disease Severity and Tumor-Immune System Interplay

The treatment options for patients with advanced salivary gland cancers (SGCs) are limited. Immune checkpoint inhibitors (ICIs) have revolutionized cancer treatment. However, the response to ICI immunotherapy is largely driven by the immune cell signatures within the tumor tissue and the para-tumoral tissue compartments. To date, there are no data on the expression of programed cell death protein-1/programed cell death protein-ligand 1 (PD-1/PD-L1) in SGC, which may enable the implementation of ICI immunotherapy for this disease. Thus, we performed an immunohistochemical analysis of PD-1 and PD-L1 expression in tumor cells and tumor-infiltrating immune cells (TIICs) in the tumor center and periphery of 62 SGC patients. The tumor periphery showed significantly higher expression of PD-L1 in tumor cells than in TIICs. Moreover, peripheral TIICs had significantly higher PD-1 expression than peripheral tumor cells. PD-1-positive tumor cells were detected exclusively in the tumor center of high-grade tumors, and most importantly, the presence of lymph node (LN) metastases and primary tumor stage significantly correlated with the presence of PD-L1-positive tumor cells in the tumor periphery. The PD-1/PD-L1 molecular signatures in SGC are clustered predominantly in the tumor periphery, reflect disease severity, and may predict the response to ICI immunotherapy in SGC patients.

Update on the most promising biomarkers of response to immune checkpoint inhibitors in clear cell renal cell carcinoma

In the last few years, the standard of care for metastatic clear cell renal cell carcinoma (mccRCC) has changed dramatically with the emergence of the immune checkpoint inhibitors (ICI): anti-PD(L)-1 used as a monotherapy or as in combination either with an anti CTLA-4 or with an anti-angiogenic molecule (VEGFR tyrosine kinase inhibitor (TKI)). These combinations are now recommended in first line setting for mccRCC, according to the last European recommendations. In the face of these new therapeutic options, the question of selecting the best treatment arises as well as the optimal sequence. Predictive biomarkers are required to guide the therapeutic choice and provide a personalized treatment for each patient. This narrative review will provide an overview of the main predictive biomarkers assessed in mccRCC treatment, with a particular focus on mRNA panel signatures.

Regulation of ST6GAL1 sialyltransferase expression in cancer cells

The ST6GAL1 sialyltransferase, which adds α2-6 linked sialic acids to N-glycosylated proteins, is overexpressed in a wide range of human malignancies. Recent studies have established the importance of ST6GAL1 in promoting tumor cell behaviors such as invasion, resistance to cell stress and chemoresistance. Furthermore, ST6GAL1 activity has been implicated in imparting cancer stem cell characteristics. However, despite the burgeoning interest in the role of ST6GAL1 in the phenotypic features of tumor cells, insufficient attention has been paid to the molecular mechanisms responsible for ST6GAL1 upregulation during neoplastic transformation. Evidence suggests that these mechanisms are multifactorial, encompassing genetic, epigenetic, transcriptional and posttranslational regulation. The purpose of this review is to summarize current knowledge regarding the molecular events that drive enriched ST6GAL1 expression in cancer cells.

Polymer-loaded hydrogels serve as depots for lactate and mimic "cold" tumor microenvironments

The burgeoning field of biomaterials for immunotherapy has aided in the understanding of foundational mechanisms of cancer immunology. In particular, implantable biomaterials can be engineered to investigate specific aspects of the tumor microenvironment either singularly or in combination. Of note, the metabolite - lactate, a byproduct of anaerobic glycolysis, is known to reprogram immune cells, resulting in increased tumor survival. An adequate model that can recapitulate intratumoral lactate concentrations does not exist. In this study, we demonstrate that a simple biomaterial platform could be developed as an instructive tool to decipher the effects of lactate in vivo. Briefly, we demonstrate that a peptide hydrogel loaded with granulocyte-macrophage colony stimulating factor and poly-(lactic-co-glycolic acid)/(lactic acid) microparticles can generate the localized lactate concentrations (∼2-22 mM) and cellular makeup of the tumor microenvironment, following subcutaneous implantation in mice. Furthermore, infiltrating immune cells adopt phenotypes similar to those seen in other in vitro and in vivo cancer models, including immunosupressive dendritic cells. This hydrogel system is a framework to interrogate immune cell modulation in cancer-like environments using safe and degradable biomaterials. Moreover, this system can be multifaceted, as incorporation of other cancer tumor environmental factors or chemotherapeutic drugs is facile and could be insightful in developing or improving immunotherapies.

Tumor-Infiltrating Lymphocytes and Their Prognostic Value in Cutaneous Melanoma

Recent breakthroughs in tumor immunotherapy such as immune checkpoint blockade (ICB) antibodies, have demonstrated the capacity of the immune system to fight cancer in a number of malignancies such as melanoma and lung cancer. The numbers, localization and phenotypes of tumor-infiltrating lymphocytes (TIL) are not only predictive of response to immunotherapy but also key modulators of disease progression. In this review, we focus on TIL profiling in cutaneous melanoma using histopathological approaches and highlight the observed prognostic value of the primary TIL subsets. The quantification of TIL in formalin-fixed tumor samples ranges from visual scoring of lymphocytic infiltrates in H&E to multiplex immunohistochemistry and immunofluorescence followed by enumeration using image analysis software. Nevertheless, TIL enumeration in the current literature primarily relies upon single marker immunohistochemistry analyses of major lymphocyte subsets such as conventional T cells (CD3, CD4, CD8), regulatory T cells (FOXP3) and B cells (CD20). We review key studies in the literature on associations between TIL subsets and patient survival. We also cover recent findings with respect to the existence of ectopic lymphoid aggregates found in the TME which are termed tertiary lymphoid structures (TLS) and are generally a positive prognostic feature. In addition to their prognostic significance, the existence of various TIL sub-populations has also been reported to predict a patient's response to ICB. Thus, the literature on the predictive potential of TIL subsets in melanoma patients receiving ICB has also been discussed. Finally, we describe recently developed state-of-the-art profiling approaches for tumor infiltrating immune cells such as digital pathology scoring algorithms (e.g., Immunoscore) and multiplex proteomics-based immunophenotyping platforms (e.g., imaging mass cytometry). Translating these novel technologies have the potential to revolutionize tumor immunopathology leading to altering our current understanding of cancer immunology and dramatically improving outcomes for patients.

Circulating Immune Cell Composition and Cancer Risk: A Prospective Study Using Epigenetic Cell Count Measures

Although ample evidence indicates that immune cell homeostasis is an important prognostic outcome determinant in patients with cancer, few studies have examined whether it also determines cancer risk among initially healthy individuals. We performed a case-cohort study including incident cases of breast (n = 207), colorectal (n = 111), lung (n = 70), and prostate (n = 201) cancer as well as a subcohort (n = 465) within the European Prospective Investigation into Cancer and Nutrition-Heidelberg cohort. Relative counts of neutrophils, monocytes, and lymphocyte sublineages were measured by qRT-PCR. HRs and 95% confidence intervals were used to measure the associations between relative counts of immune cell and cancer risks. When relative counts of immune cell types were taken individually, a significant positive association was observed between relative counts of FOXP3⁺ regulatory T cells (Tregs) and lung cancer risk, and significant inverse associations were observed between relative CD8⁺ counts and risks of lung and breast cancer (overall and ER+ subtype). Multivariable models with mutual adjustments across immune markers showed further significant positive associations between higher relative FOXP3⁺ T-cell counts and increased risks of colorectal and breast cancer (overall and ER- subtype). No associations were found between immune cell composition and prostate cancer risk. These results affirm the relevance of elevated FOXP3⁺ Tregs and lower levels of cytotoxic (CD8⁺) T cells as risk factors for tumor development. SIGNIFICANCE: This epidemiologic study supports a role for both regulatory and cytotoxic T cells in determining cancer risk among healthy individuals.See related commentary by Song and Tworoger, p. 1801.

Flow cytometry and targeted immune transcriptomics identify distinct profiles in patients with chronic myeloid leukemia receiving tyrosine kinase inhibitors with or without interferon-α

Background

Tumor cells have evolved complex strategies to escape immune surveillance, a process which involves NK cells and T lymphocytes, and various immunological factors. Indeed, tumor cells recruit immunosuppressive cells [including regulatory T-cells (Treg), myeloid-derived suppressor cells (MDSC)] and express factors such as PD-L1. Molecularly targeted therapies, such as imatinib, have off-target effects that may influence immune function. Imatinib has been shown to modulate multiple cell types involved in anti-cancer immune surveillance, with potentially detrimental or favorable outcomes. Imatinib and other tyrosine kinase inhibitors (TKIs) in chronic myeloid leukemia (CML) have dramatically changed disease course. Our study aimed to characterize the different populations of the immune system in patients with CML affected by their treatment.

Methods

Forty-one patients with CML [33 treated with TKIs and 8 with TKIs plus interferon (IFN)-α] and 20 controls were enrolled in the present study. Peripheral blood populations of the immune system [referred to as the overview of immune system (OVIS) panel, Treg cells and MDSCs] and PD-1 expression were evaluated by flow cytometry. The immunological profile was assessed using the mRNA Pan-Cancer Immune Profiling Panel and a NanoString nCounter FLEX platform.

Results

Patients receiving combination therapy (TKIs + IFN-α) had lower numbers of lymphocytes, particularly T cells [838/µL (95% CI 594–1182)] compared with healthy controls [1500/µL (95% CI 1207 – 1865), p = 0.017]. These patients also had a higher percentage of Treg (9.1%) and CD4⁺PD-1⁺ cells (1.65%) compared with controls [Treg (6.1%) and CD4⁺/PD-1⁺(0.8%); p ≤ 0.05]. Moreover, patients treated with TKIs had more Mo-MDSCs (12.7%) whereas those treated with TKIs + IFN-α had more Gr-MDSC (21.3%) compared to controls [Mo-MDSC (11.4%) and Gr-MDSC (8.48%); p ≤ 0.05]. CD56^bright NK cells, a cell subset endowed with immune-regulatory properties, were increased in patients receiving TKIs plus IFN-α compared with those treated with TKIs alone. Interestingly, serum IL-21 was significantly lower in the TKIs plus IFN-α cohort. Within the group of patients treated with TKI monotherapy, we observed that individuals receiving 2nd generation TKIs had lower percentages of CD4⁺ Treg (3.63%) and Gr-MDSC (4.2%) compared to patients under imatinib treatment (CD4⁺ Treg 6.18% and Gr-MDSC 8.2%), but higher levels of PD-1-co-expressing CD4⁺ cells (1.92%).

Conclusions

Our results suggest that TKIs in combination with IFN-α may promote an enhanced immune suppressive state.

Prediagnostic Immune Cell Profiles and Breast Cancer

IMPORTANCE

Higher overall leukocyte counts in women may be associated with increased risk of breast cancer, but the association of specific leukocyte subtypes with breast cancer risk remains unknown.

OBJECTIVE

To determine associations between circulating leukocyte subtypes and risk of breast cancer.

DESIGN, SETTING, AND PARTICIPANTS

Between 2003 and 2009, the Sister Study enrolled 50 884 women who had a sister previously diagnosed with breast cancer but were themselves breast cancer free. A case-cohort subsample was selected in July 2014 from the full Sister Study cohort. Blood samples were obtained at baseline, and women were followed up through October 2016. Data analysis was performed in April 2019.

MAIN OUTCOMES AND MEASURES

The main outcome was the development of breast cancer in women. Whole-blood DNA methylation was measured, and methylation values were deconvoluted using the Houseman method to estimate proportions of 6 leukocyte subtypes (B cells, natural killer cells, CD8+ and CD4+ T cells, monocytes, and granulocytes). Leukocyte subtype proportions were dichotomized at their population median value, and Cox proportional hazard models were used to estimate associations with breast cancer.

RESULTS

Among 2774 non-Hispanic white women included in the analysis (mean [SD] age at enrollment, 56.6 [8.8] years), 1295 women were randomly selected from the full cohort (of whom 91 developed breast cancer) along with an additional 1479 women who developed breast cancer during follow-up (mean [SD] time to diagnosis, 3.9 [2.2] years). Circulating proportions of B cells were positively associated with later breast cancer (hazard ratio [HR], 1.17; 95% CI, 1.01-1.36; P = .04). Among women who were premenopausal at blood collection, the association between B cells and breast cancer was significant (HR, 1.38; 95% CI, 1.05-1.82; P = .02), and an inverse association for circulating proportions of monocytes was found (HR, 0.75; 95% CI, 0.57-0.99; P = .05). Among all women, associations between leukocyte subtypes and breast cancer were time dependent: higher monocyte proportions were associated with decreased near-term risk (within 1 year of blood collection, HR, 0.62; 95% CI, 0.43-0.89; P = .01), whereas higher B cell proportions were associated with increased risk 4 or more years after blood collection (HR, 1.38; 95% CI, 1.15-1.67; P = .001).

CONCLUSIONS AND RELEVANCE

Circulating leukocyte profiles may be altered before clinical diagnoses of breast cancer and may be time-dependent markers for breast cancer risk, particularly among premenopausal women.

Optimisation of multiplex immunofluorescence for a non-spectral fluorescence scanning system

The use of multi-colour immunofluorescence (IF) for immunophenotyping in formalin-fixed paraffin-embedded tissue sections is gaining popularity worldwide. This technique allows for the simultaneous detection of multiple markers on the same tissue section, thereby yielding more complex information than is possible by chromogenic immunohistochemistry (IHC). However, many commercially-available multiplex IF kits are designed for use in conjunction with a multispectral imaging system, to which many research groups have limited access. Here we present two 5-colour IF panels designed for T cell characterisation in human colorectal tissue, which can be imaged using a non-spectral fluorescence slide scanner with standard band-pass filters. We describe the optimisation process and the key considerations in developing a multiplex fluorescence assay, and discuss some of the advantages and disadvantages of using multiplex IF with a non-spectral imaging system.

External validation of the systemic immune-inflammation index as a prognostic factor in metastatic renal cell carcinoma and its implementation within the international metastatic renal cell carcinoma database consortium model

BACKGROUND

We conducted a study to validate the influence of the systemic immune-inflammation index (SII) on overall survival (OS) in patients with metastatic renal cell carcinoma (mRCC) and to verify whether the implementation of the SII in place of neutrophil and platelet counts within the International Metastatic Renal Cell Carcinoma Consortium (IMDC) model might increase its prognostic accuracy.

PATIENTS AND METHODS

We retrospectively analyzed consecutive patients with mRCC, who were treated with first-line tyrosine kinase inhibitors from 2008 to 2016 in two major oncology centres in Poland. We stratified patients into low SII (< 730) and high SII (≥ 730) groups according to a recent literature report. We used multivariable Cox proportional hazards regressions (CPHRs) to assess the impact of the SII on OS and concordance, global 'goodness-of-fit', calibration and reclassification measures to quantify a potential prognostic benefit from the modification of the IMDC model.

RESULTS

Overall, 502 patients (294 with low and 208 with high SII) were included. Median OS was 36.7 months [95% confidence interval (CI) 30.4-41.5 months] and 17.0 months (95% CI 12.5-19.6 months) in the low and high SII groups, respectively. The SII status was significant in CPHRs with the hazard ratio ranging from 1.38 to 1.68. All prognostic accuracy measures favored the SII-modified-IMDC model over the original IMDC model.

CONCLUSIONS

Using an external dataset, we showed that high SII was an independent factor for poor OS. The addition of the SII to the IMDC model in place of neutrophil and platelet counts increased the model's prognostic performance.