Peripheral blood immune cell-based biomarkers in anti-PD-1/PD-L1 therapy

Th1-poised naive CD4 T cell subpopulation reflects anti-tumor immunity and autoimmune disease

Naïve CD4 T cells are traditionally viewed as a quiescent, homogeneous, resting population, but emerging evidence reveals their heterogeneity, which can be crucial for understanding disease contexts and therapeutic outcomes. In this study, we identify distinct subpopulations within both murine and human naïve CD4 T cells by single cell-RNA-sequencing (scRNA-seq), particularly focusing on a subpopulation that expresses super-high levels of interleukin-7 receptor (IL-7Rsup-hi), along with CD97, IL-18R, and Ly6C. This subpopulation, absent in the thymus and peripherally induced, exhibits type 1 helper T cell (Th1)-poised characteristics and contributes to the inhibition of cancer progression in B16F10 tumor-bearing mice. In humans, this IL-7Rsup-hi subpopulation expressing CD97 correlates with the responsiveness to anti-PD-1 therapy in cancer patients and the disease state of multiple sclerosis. By elucidating the heterogeneity of naive CD4 T cells and identifying a Th1-poised subpopulation capable of robust type 1 responses, we highlight the importance of this heterogeneity in inflammatory conditions for defining the disease states and predicting drug responsiveness.

Immune Signatures of Solid Tumor Patients Treated With Immune Checkpoint Inhibitors: An Observational Study

PURPOSE

Our study aimed to comprehensively describe the features of peripheral blood multiple immune cell phenotypes in solid tumor patients during pretreatment and after immunotherapy, providing a more convenient approach for studying the prognosis of immunotherapy in different solid tumor patients.

METHODS

We prospectively recruited patients with advanced solid tumors from Peking Union Medical College Hospital (PUMCH) between February 2023 and April 2024. Using multicolor flow cytometry, our study comprehensively observed and described the signatures of peripheral blood lymphocyte subsets including activation, proliferation, function, naïve memory, and T cell exhaustion immune cell subsets in this population of pretreatment and after immunotherapy.

RESULTS

Our study enrolled 59 advanced solid tumor patients with immunotherapy and 59 healthy controls were matched by age and gender. The results demonstrated a marked upregulation in the expression of lymphocyte activation markers CD38 and HLA-DR, as well as exhaustion and proliferation markers PD-1 and Ki67, in solid tumor patients compared to healthy controls. After immune checkpoint blockade (ICB) treatment, mainly the expression of Ki67CD4+T and HLA-DRCD38CD4+T, was significantly upregulated compared to pretreatment levels (p = 0.017, p = 0.019, respectively). We further found that gynecological tumors with better prognoses had higher baseline activation levels of CD4+ T cells compared to other solid tumors with poorer prognoses.

CONCLUSION

Our study elucidated the characteristics of different lymphocyte subsets in the peripheral blood of solid tumor patients. Further research revealed changes in the phenotypes of different lymphocyte subsets after ICIs treatment, with the activated phenotype of CD4+ T cells playing a crucial role in the antitumor effect. This lays the groundwork for further exploration of prognostic biomarkers and predictive models for cancer patients with immunotherapy.

Efficient Predictor for Immunotherapy Efficacy: Detecting Pan-Clones Effector Tumor Antigen-Specific T Cells in Blood by Nanoparticles Loading Whole Tumor Antigens

Cancer involves tumor cells and tumor-specific immunity. The ability to accurately quantify tumor-specific immunity is limited. Most immunotherapies function by activating new effector tumor antigen-specific T cells (ETASTs) or reactivating the pre-existing ETASTs repertoire. Therefore, the amount of ETASTs can be used to characterize immunotherapy efficacy. Tumor antigens are highly heterogeneous and detecting most ETASTs is challenging. Therefore, nanoparticles loading whole-cell tumor antigens are used to activate and detect pan-clones ETASTs in the blood. The differences between ETASTs and other T cells are transformed into activated and non-activated states. By measuring markers of the activated status and cytotoxic function of ETASTs, it can distinguish ETASTs from other T cells. ETASTs in patients with lung cancer are higher than those in healthy individuals and those with benign pulmonary nodules. Therapeutic efficacy positively correlated with the number of ETASTs in the blood. ETATS levels increase only in the blood of patients who respond to immunotherapy. Single-cell sequencing studies validated these findings. This study provides a highly accurate, specific, non-invasive, and efficient biomarker for predicting immunotherapy efficacy in lung and other cancers. This method can also be applied to evaluate the efficacy of other treatments, such as radiotherapy, oncolytic viruses, and nanomedicine-based therapies.

The Efficacy of Curcumin in Reducing Immunosuppressive States of Peripheral Blood Mononuclear Cells Extracted From Oral Squamous Cell Carcinoma Patients: An In Vitro Study

Background and objectives Prior studies have shown that patients with oral cancer overexpress programmed cell death 1 (PD-1) and programmed cell death ligand 1 (PD-L1) in cancer cells and immunocompetent lymphocytes. Current immunotherapeutic interventions include antibodies targeting PD-1/PD-L1. This observational, in vitro, cell culture-based study aimed to assess the concentrations of PD-1 and PD-L1 in the peripheral blood mononuclear cells (PBMCs) of patients with oral squamous cell carcinoma (OSCC) and compare their levels with those in healthy controls, both pre- and post-curcumin intervention. This study also compared the soluble fraction of PD-L1 in the serum of patients with that in controls. We aimed to determine a cutoff level for cell surface PD-1/PD-L1 to differentiate between patients and healthy controls, in order to identify potential targets for immunotherapy. Methodology Blood samples (5 mL) were collected from both controls (n=20) and patients (n=20). Of this, 2 mL was used to collect serum samples, and 3 mL was used for isolation and culture of PBMCs. Cells were analyzed pre- and post-intervention with curcumin for PD-1 and PD-L1 expression. Results This study provides relevant data regarding cellular and serum PD-1/PD-L1 levels in patients with OSCC, which were significantly higher than in controls. Intervention with curcumin decreased PD-L1/PD-1 levels, indicating the therapeutic efficacy of curcumin in suppressing immunotolerance in the tumor microenvironment. We also found that cell lysate PD-L1 and PD-1 had a sensitivity of 75% and specificity of 89%, with cutoff values of 0.602 and 5.53 ng/mL for PD-L1 and PD-1, respectively. The receiver operating characteristic (ROC) curve analysis determined that these markers were suitable for OSCC diagnosis and identifying the appropriate cohort for immunotherapy. Conclusions Our study showed that serum and PBMC lysate PD-1 and PD-L1 levels were higher in advanced cancer cases compared to patients with localized disease without metastasis. Curcumin reduced the levels of PD-1 and PD-L1 in PBMC lysates. Further studies and clinical trials are required to gain deeper insights into its utility as an effective chemo adjuvant.

Efficient Biomarker for Immunotherapy: Measuring Broad Clones Effector Tumor Antigen-Specific T Cells in the Blood of Esophageal Cancer Patients

Cancer is the result of the interactions between tumor cells and tumor-specific immune responses. The current biomarkers detect tumor cells' properties, but accurate measurement of tumor-specific immunity is lacking. Most immunotherapies work by activating new effector tumor antigen-specific T cells (ETASTs) or reactivating pre-existing ETASTs' repertoire. The responses to immunotherapy depend on the increase of ETASTs. The amount of ETASTs, especially in blood, is critical for therapeutic efficacy. Distinguishing ETASTs from other T cells by their structural characteristics is difficult. Therefore, nanoparticles loading whole tumor antigens are utilized to activate broad clones ETASTs pre-existing in peripheral blood, followed by detecting them. Thus, the differences between ETASTs and other T cells are transformed to the differences between activated states and unactivated states. By measuring the markers of activated states and cytotoxic functions, we can distinguish ETASTs from other T cells. Nanoparticles loading mixed multiple allogeneic tumor tissue lysates or mixed multiple tumor cell lines can be utilized as universal nanoparticles to replace nanoparticles loading personalized tumor tissue. ETASTs (TATAN-activated CD8+IFN-γ+) in esophageal cancer patients are more than those in healthy people. Measurement of the ETASTs in the blood of esophageal cancer patients before and after ongoing therapy showed that ETATSs increased in the blood of patients who were responsive to immunotherapy but did not increase in the blood of nonresponders. These illustrated that therapeutic efficacy was positively correlated with the level of ETASTs in PBMC. Altogether, this study provides us a highly accurate and specific biomarker for predicting the therapeutic efficacy of cancer immunotherapy and potentially other therapies, such as radiotherapy.

Higher objective responses by hepatic arterial infusion chemotherapy following atezolizumab and bevacizumab failure than when used as initial therapy in hepatocellular carcinoma: a retrospective study

PURPOSE

Atezolizumab/bevacizumab (atezo-bev) is the first-line chemotherapy for patients with unresectable hepatocellular carcinoma (HCC). However, hepatic artery infusion chemotherapy (HAIC) can be used as an alternative. Our aim was to compare the prognosis of HAIC treatment between newly diagnosed patients and patients treated after failure of atezo-bev.

METHODS

We retrospectively assessed 73 patients with HCC treated with HAIC between January 2022 and September 2023. Fifty-seven patients were treated with HAIC at initial diagnosis, while 16 were treated with HAIC after first-line atezo-bev combination chemotherapy. We evaluated tumor responses, such as overall survival (OS), progression-free survival (PFS), and objective response rate (ORR).

RESULTS

No significant difference was observed in either OS or PFS between patients with HCC treated with HAIC at the initial diagnosis and those treated after atezo-bev treatment failure. However, the ORR of the initial HAIC group was 19.6% and that of the HAIC group after atezo-bev therapy failure was 43.6%, which was a statistically significantly difference.

CONCLUSION

Although no significant difference was observed for OS and PFS, the ORR of patients in the HAIC group after the failure of atezo-bev therapy was superior to that of newly diagnosed patients. HAIC may prolong survival in patients with HCC after atezo-bev treatment failure.

Tumor lysis syndrome in a patient with advanced lung squamous cell carcinoma undergoing combined therapy with a programmed cell death protein 1 inhibitor and first‑line chemotherapy: A case report

Tumor lysis syndrome (TLS) is a rare but serious complication in patients with solid tumors. It is characterized by a complex array of metabolic disturbances and clinical symptoms, resulting from the release of cellular contents into the bloodstream after tumor cell lysis. The present study reports the case of a patient with advanced lung squamous cell carcinoma (SCC) who developed TLS following combined treatment with PD-1 inhibitors and first-line chemotherapy. The treatment strategy included intravenous fluid replacement, urine alkalinization, uric acid reduction, renal protection and electrolyte stabilization, leading to the normalization of laboratory values. After one cycle of the combined therapy, the patient achieved a partial response, classified using the Response Evaluation Criteria in Solid Tumours 1.1 criteria. To the best of our knowledge, this is the first reported case of TLS in a patient with advanced lung SCC receiving concurrent PD-1 inhibitor and chemotherapy treatment. Given the increasing use of PD-1 inhibitors, it is essential to remain vigilant about the potential for TLS in solid tumors. Prompt intervention in high-risk patients, ongoing monitoring after treatment, and early detection of TLS are vital to improve patient adherence, ensure continuity of care and enhance outcomes.

Biomarkers and computational models for predicting efficacy to tumor ICI immunotherapy

Numerous studies have shown that immune checkpoint inhibitor (ICI) immunotherapy has great potential as a cancer treatment, leading to significant clinical improvements in numerous cases. However, it benefits a minority of patients, underscoring the importance of discovering reliable biomarkers that can be used to screen for potential beneficiaries and ultimately reduce the risk of overtreatment. Our comprehensive review focuses on the latest advancements in predictive biomarkers for ICI therapy, particularly emphasizing those that enhance the efficacy of programmed cell death protein 1 (PD-1)/programmed cell death-ligand 1 (PD-L1) inhibitors and cytotoxic T-lymphocyte antigen-4 (CTLA-4) inhibitors immunotherapies. We explore biomarkers derived from various sources, including tumor cells, the tumor immune microenvironment (TIME), body fluids, gut microbes, and metabolites. Among them, tumor cells-derived biomarkers include tumor mutational burden (TMB) biomarker, tumor neoantigen burden (TNB) biomarker, microsatellite instability (MSI) biomarker, PD-L1 expression biomarker, mutated gene biomarkers in pathways, and epigenetic biomarkers. TIME-derived biomarkers include immune landscape of TIME biomarkers, inhibitory checkpoints biomarkers, and immune repertoire biomarkers. We also discuss various techniques used to detect and assess these biomarkers, detailing their respective datasets, strengths, weaknesses, and evaluative metrics. Furthermore, we present a comprehensive review of computer models for predicting the response to ICI therapy. The computer models include knowledge-based mechanistic models and data-based machine learning (ML) models. Among the knowledge-based mechanistic models are pharmacokinetic/pharmacodynamic (PK/PD) models, partial differential equation (PDE) models, signal networks-based models, quantitative systems pharmacology (QSP) models, and agent-based models (ABMs). ML models include linear regression models, logistic regression models, support vector machine (SVM)/random forest/extra trees/k-nearest neighbors (KNN) models, artificial neural network (ANN) and deep learning models. Additionally, there are hybrid models of systems biology and ML. We summarized the details of these models, outlining the datasets they utilize, their evaluation methods/metrics, and their respective strengths and limitations. By summarizing the major advances in the research on predictive biomarkers and computer models for the therapeutic effect and clinical utility of tumor ICI, we aim to assist researchers in choosing appropriate biomarkers or computer models for research exploration and help clinicians conduct precision medicine by selecting the best biomarkers.

Recent advances in cellular immunotherapy for lymphoid malignancies

Cellular immunotherapy with chimeric antigen receptor (CAR) T-cells has revolutionized the treatment of lymphoid malignancies. This review addresses the need for CAR expression in our endogenous T-cells to kill tumor cells with a focus on the basic principles of T-cell receptor recognition of major histocompatibility complex-peptide complexes. We review the factors associated with CAR T-cell outcomes and recent efforts to employ CAR T-cells in earlier lines of therapy. We also discuss the value of bispecific T-cell engagers as off-the-shelf products with better toxicity profiles. Finally, natural killer cells are discussed as an important cellular immunotherapy platform with the potential to broaden immunotherapeutic applications beyond lymphoid malignancies.

Peripheral CD8+CD28+ T lymphocytes predict the efficacy and safety of PD-1/PD-L1 inhibitors in cancer patients

Background

Programmed cell death protein-1/programmed cell death ligand-1 (PD-1/PD-L1) inhibitors works by reactivating immune cells. Considering the accessibility of noninvasive liquid biopsies, it is advisable to employ peripheral blood lymphocyte subsets to predict immunotherapy outcomes.

Methods

We retrospectively enrolled 87 patients with available baseline circulating lymphocyte subset data who received first-line PD-1/PD-L1 inhibitors at Peking Union Medical College Hospital between May 2018 and April 2022. Immune cell counts were determined by flow cytometry.

Results

Patients who responded to PD-1/PD-L1 inhibitors had significantly higher circulating CD8+CD28+ T-cell counts (median [range] count: 236 [30-536] versus 138 [36-460]/μL, p < 0.001). Using 190/μL as the cutoff value, the sensitivity and specificity of CD8+CD28+ T cells for predicting immunotherapy response were 0.689 and 0.714, respectively. Furthermore, the median progression-free survival (PFS, not reached versus 8.7 months, p < 0.001) and overall survival (OS, not reached versus 16.2 months, p < 0.001) were significantly longer in the patients with higher CD8+CD28+ T-cell counts. However, the CD8+CD28+ T-cell level was also associated with the incidence of grade 3-4 immune-related adverse events (irAEs). The sensitivity and specificity of CD8+CD28+ T cells for predicting irAEs of grade 3-4 were 0.846 and 0.667, respectively, at the threshold of CD8+CD28+ T cells ≥ 309/μL.

Conclusions

High circulating CD8+CD28+ T-cell levels is a potential biomarker for immunotherapy response and better prognosis, while excessive CD8+CD28+ T cells (≥ 309/μL) may also indicate the emergence of severe irAEs.

Systemic immune modulation by stereotactic radiotherapy in early-stage lung cancer

We performed a prospective study of circulating immune cell changes after stereotactic body radiotherapy (SBRT) in 50 early-stage NSCLC patients. We found no significant increase in CD8⁺ cytotoxic T lymphocytes at first follow-up (the primary endpoint) but detected a significant increase in expanding Ki-67⁺CD8⁺ and Ki-67⁺CD4⁺ T-cell fractions in patients treated with 10 Gy or less per fraction. SBRT can induce significant expansion in circulating effector T-cells immediately post-treatment.

Clonal expansion of resident memory T cells in peripheral blood of patients with non-small cell lung cancer during immune checkpoint inhibitor treatment

BACKGROUND

Immune checkpoint inhibitors (ICIs) are an essential treatment for non-small cell lung cancer (NSCLC). Currently, the tumor-related intrinsic factors in response to ICIs have mostly been elucidated in tissue samples. However, tissue immune status and changes in the immune microenvironment can also be reflected and monitored through peripheral blood.

METHODS

Single-cell RNA and T cell receptor (scTCR) sequencing were conducted using peripheral blood mononuclear cells (PBMCs) from 60 patients with stage IV NSCLC. Those samples were prospectively acquired from patients treated with anti-PD(L)-1 therapy for advanced lung cancer. Based on the clinical outcomes, samples were classified as durable clinical benefit (DCB) and non-durable clinical benefit (NCB). The samples constituted paired longitudinal samples, consisting of pre-treatment and on-treatment. Additionally, PBMC samples from 60 healthy donors from the Asian Immune Diversity Atlas project were used as a control.

RESULTS

The dynamic changes in major cell types between pre-treatment and on-treatment PBMCs were associated with an increase in proliferating T cells and NK cells in both DCB and NCB groups. Among T cell subtypes, effector memory CD8⁺ T cells (CD8⁺ T_EM_GZMK_PDCD1) were increased after ICI treatment in both DCB and NCB. From the lineage trajectory analysis, effector memory CD8⁺ T cells resided at the bifurcation point, which has the potential to differentiate into lineages with precursor exhausted CD8⁺ T cells (CD8⁺ T_CM cells) assumed to be related to the ICI response. From the scTCR-seq, effector memory CD8⁺ T cells along with T cells recognizing unknown antigen expanded and composed of novel clones skewed toward dysfunctional status, especially in on-treatment samples of the DCB group. The extent of immunophenotype conversion capabilities of the TCR with effector memory CD8⁺ T cells showed remarkable variation in the on-treatment sample in the DCB group.

CONCLUSION

A transitioning T cell subtype identified in PBMCs might be related to the prolonged ICI response. From our study, expansion of effector memory CD8⁺ T cells with novel TCRs in PBMCs after ICI treatment could contribute to a better clinical outcome in patients with NSCLC. This proof-of-concept research strengthens the use of non-invasive PBMCs in studying systemic changes of immune reactions related to the ICI treatment.

Dynamic changes in peripheral blood monocytes early after anti-PD-1 therapy predict clinical outcomes in hepatocellular carcinoma

Immune checkpoint inhibitors are effective for advanced hepatocellular carcinoma (HCC), but there remains a need for peripheral blood biomarkers to predict the clinical response. Here, we analyzed the peripheral blood of 45 patients with advanced HCC who underwent nivolumab. During treatment, frequency of classical monocytes (CD14+CD16-) was increased on day 7, and the fold increase in the frequency on day 7 over day 0 (cMonocyteD7/D0) was significantly higher in patients with durable clinical benefit (DCB) than in patients with non-DCB (NDB). When we analyzed transcriptomes of classical monocytes, CD274, gene encoding PD-L1, was upregulated in NDB patients compared to DCB patients at day 7. Notably, gene signature of suppressive tumor-associated macrophages, or IL4l1+PD-L1+IDO1+ macrophages, was enriched after treatment in NDB patients, but not in DCB patients. Accordingly, the fold increase in the frequency of PD-L1+ classical monocytes at day 7 over day 0 (cMonocyte-PDL1D7/D0) was higher in NDB patients than DCB patients. The combined biomarker cMonocyteD7/D0/cMonocyte-PDL1D7/D0 was termed the "monocyte index", which was significantly higher in DCB patients than NDB patients. Moreover, the monocyte index was an independent prognostic factor for survival. Overall, our results suggest that early changes of circulating classical monocytes, represented as a monocyte index, could predict clinical outcomes of advanced HCC patients undergoing anti-PD-1 therapy.

Blood T-cell profiling in metastatic melanoma patients as a marker for response to immune checkpoint inhibitors combined with radiotherapy

BACKGROUND

The addition of stereotactic ablative radiotherapy (SABR) to immune checkpoint inhibitors (ICIs) has the potential to significantly improve outcomes in the treatment of metastatic melanoma. We analysed peripheral blood immune cells of patients receiving combination SABR and ICI to detect the effect of treatment and identify potential biomarkers that predict outcome.

METHODS

24 polymetastatic melanoma patients participated in the SABR IMPACT trial, receiving standard dose immunotherapy with anti-PD-1 and/or anti-CTLA-4 and stereotactic ablative radiotherapy to one site. Comprehensive immunophenotyping of T-cells was performed with flow cytometry on blood samples from 13 patients at baseline and following the first 4 cycles of treatment.

RESULTS

Following four cycles of immunotherapy and SABR, the proportion of naïve subsets were reduced within both the CD4 and CD8 T-cell lineages. Independently, SABR resulted in increased expression of PD-1 (p = 0.019) and ICOS (p = 0.046) on the CD8+ T-cells, accompanied by a reduction in regulatory T-cell frequencies (p = 0.048). A multivariate discriminant analysis revealed a baseline signature of lower levels of CD8+ naive T-cells and higher expression of TIM-3 on regulatory T-cells and memory T-cells better predicted response.

CONCLUSION

The combination of immunotherapy and SABR changed the immunophenotype of blood T cells, with some shifts attributable to SABR. Importantly, we identified a T-cell signature at baseline that best predicted response. Validation of these findings in an independent cohort could confirm these as biomarkers at baseline or early during treatment, and whether these can be utilised to stratify patients for high or low intensity treatment to reduce toxicity.

An anti-PD-1–GITR-L bispecific agonist induces GITR clustering-mediated T cell activation for cancer immunotherapy

Costimulatory receptors such as glucocorticoid-induced tumor necrosis factor receptor–related protein (GITR) play key roles in regulating the effector functions of T cells. In human clinical trials, however, GITR agonist antibodies have shown limited therapeutic effect, which may be due to suboptimal receptor clustering-mediated signaling. To overcome this potential limitation, a rational protein engineering approach is needed to optimize GITR agonist-based immunotherapies. Here we show a bispecific molecule consisting of an anti-PD-1 antibody fused with a multimeric GITR ligand (GITR-L) that induces PD-1-dependent and FcγR-independent GITR clustering, resulting in enhanced activation, proliferation and memory differentiation of primed antigen-specific GITR⁺PD-1⁺ T cells. The anti-PD-1–GITR-L bispecific is a PD-1-directed GITR-L construct that demonstrated dose-dependent, immunologically driven tumor growth inhibition in syngeneic, genetically engineered and xenograft humanized mouse tumor models, with a dose-dependent correlation between target saturation and Ki67 and TIGIT upregulation on memory T cells. Anti-PD-1–GITR-L thus represents a bispecific approach to directing GITR agonism for cancer immunotherapy.

Alvarez and colleagues develop a bispecific anti-PD-1–GITR-L agonist that activates T cells via a mechanism distinct from those found with individual PD-1 and GITR-L agonists and demonstrate its antitumor activity in mice and nonhuman primates.

Peripheral lymphocyte count as a surrogate marker of immune checkpoint inhibitor therapy outcomes in patients with non-small-cell lung cancer

Degree of expression of programmed death-ligand 1 (PD-L1) is related with Immune check point inhibitors (ICIs) response but it needs sufficient tumor tissue. There is unmet need for easily accessible and prognostic peripheral blood (PB) biomarkers. We investigated the application of serum peripheral lymphocyte count (PLC) as a predictive PB biomarker for ICI response in patients with NSCLC. We conducted a retrospective study and reviewed the patients with NSCLC who were treated with ICIs from April 1, 2016, to March 31, 2019. The PLC before and after 1 month of immunotherapy was collected. We evaluated the association between PLC and progression-free survival (PFS), overall survival (OS) and adverse events. A total of 231 patients were treated with ICIs for NSCLC. The median follow-up period was 4.7 months and the disease progressed in 138 patients (59.7%). Compared with the lowest quartile (Q1: the lowest 25%), the highest quartile (Q4: the highest 25%) of post-treatment PLC showed a significantly higher PFS (HR 0.28, 95% CI 0.16-0.52) and OS (HR 0.35, 95% CI 0.19-0.65) in the adjusted model. An association between adverse events and PLC was not observed. We revealed that an increased pre- and post-treatment PLC was associated with favorable PFS and OS with NSCLC patients treated with ICIs. PLC could be a helpful for ICI responses in NSCLC.

PD-1 inhibition in advanced myeloproliferative neoplasms

This is the first report demonstrating the safety and lack of efficacy of pembrolizumab treatment in patients with advanced MPNs.

Pembrolizumab was associated with changes in the immune milieu that could potentially support antitumor immunity in patients with advanced MPNs.

Myelofibrosis (MF) is a clonal stem cell neoplasm characterized by abnormal JAK-STAT signaling, chronic inflammation, cytopenias, and risk of transformation to acute leukemia. Despite improvements in the therapeutic options for patients with MF, allogeneic hematopoietic stem cell transplantation remains the only curative treatment. We previously demonstrated multiple immunosuppressive mechanisms in patients with MF, including increased expression of programmed cell death protein 1 (PD-1) on T cells compared with healthy controls. Therefore, we conducted a multicenter, open-label, phase 2, single-arm study of pembrolizumab in patients with Dynamic International Prognostic Scoring System category of intermediate-2 or greater primary, post-essential thrombocythemia or post-polycythemia vera myelofibrosis that were ineligible for or were previously treated with ruxolitinib. The study followed a Simon 2-stage design and enrolled a total of 10 patients, 5 of whom had JAK2^V617mutation, 2 had CALR mutation, and 6 had additional mutations. Most patients were previously treated with ruxolitinib. Pembrolizumab treatment was well tolerated, but there were no objective clinical responses, so the study closed after the first stage was completed. However, immune profiling by flow cytometry, T-cell receptor sequencing, and plasma proteomics demonstrated changes in the immune milieu of patients, which suggested improved T-cell responses that can potentially favor antitumor immunity. The fact that these changes were not reflected in a clinical response strongly suggests that combination immunotherapeutic approaches rather than monotherapy may be necessary to reverse the multifactorial mechanisms of immune suppression in myeloproliferative neoplasms. This trial was registered at www.clinicaltrials.gov as #NCT03065400.

Peripheral Blood-Based Biomarkers for Immune Checkpoint Inhibitors

As cancer immunotherapy using immune checkpoint inhibitors (ICIs) is rapidly evolving in clinical practice, it is necessary to identify biomarkers that will allow the selection of cancer patients who will benefit most or least from ICIs and to longitudinally monitor patients' immune responses during treatment. Various peripheral blood-based immune biomarkers are being identified with recent advances in high-throughput multiplexed analytical technologies. The identification of these biomarkers, which can be easily detected in blood samples using non-invasive and repeatable methods, will contribute to overcoming the limitations of previously used tissue-based biomarkers. Here, we discuss the potential of circulating immune cells, soluble immune and inflammatory molecules, circulating tumor cells and DNA, exosomes, and the blood-based tumor mutational burden, as biomarkers for the prediction of immune responses and clinical benefit from ICI treatment in patients with advanced cancer.

Systems biology informed neural networks (SBINN) predict response and novel combinations for PD-1 checkpoint blockade

Anti-PD-1 immunotherapy has recently shown tremendous success for the treatment of several aggressive cancers. However, variability and unpredictability in treatment outcome have been observed, and are thought to be driven by patient-specific biology and interactions of the patient's immune system with the tumor. Here we develop an integrative systems biology and machine learning approach, built around clinical data, to predict patient response to anti-PD-1 immunotherapy and to improve the response rate. Using this approach, we determine biomarkers of patient response and identify potential mechanisms of drug resistance. We develop systems biology informed neural networks (SBINN) to calculate patient-specific kinetic parameter values and to predict clinical outcome. We show how transfer learning can be leveraged with simulated clinical data to significantly improve the response prediction accuracy of the SBINN. Further, we identify novel drug combinations and optimize the treatment protocol for triple combination therapy consisting of IL-6 inhibition, recombinant IL-12, and anti-PD-1 immunotherapy in order to maximize patient response. We also find unexpected differences in protein expression levels between response phenotypes which complement recent clinical findings. Our approach has the potential to aid in the development of targeted experiments for patient drug screening as well as identify novel therapeutic targets.

Blood biomarkers associated to complete pathological response on NSCLC patients treated with neoadjuvant chemoimmunotherapy included in NADIM clinical trial

BACKGROUND

Immunotherapy is being tested in early-stage non-small cell lung cancer (NSCLC), and achieving higher rates of complete pathological responses (CPR) as compared to standard of care. Early identification of CPR patients has vital clinical implications. In this study, we focused on basal peripheral immune cells and their treatment-related changes to find biomarkers associated to CPR.

METHODS

Blood from 29 stage IIIA NSCLC patients participating in the NADIM trial (NCT03081689) was collected at diagnosis and post neoadjuvant treatment. More than 400 parameters of peripheral blood mononuclear cells (PBMCs) phenotype and plasma soluble factors were analyzed.

RESULTS

Neoadjuvant chemoimmunotherapy altered more than 150 immune parameters. At diagnosis, 11 biomarkers associated to CPR were described, with an area under the ROC curve >0.70 and p-value <.05. CPR patients had significantly higher levels of CD4+ PD-1+ cells, NKG2D, and CD56 expression on T CD56 cells, intensity of CD25 expression on CD4+ CD25hi+ cells and CD69 expression on intermediate monocytes; but lower levels of CD3+ CD56- CTLA-4+ cells, CD14++ CD16+ CTLA-4+ cells, CTLA-4 expression on T CD56 cells and lower levels of b-NGF, NT-3, and VEGF-D in plasma compared to non-CPR. Post treatment, CPR patients had significantly higher levels of CD19 expression on B cells, BCMA, 4-1BB, MCSF, and PARC and lower levels of MPIF-1 and Flt-3L in plasma compared to non-CPR.

CONCLUSIONS

Patients achieving CPR seem to have a distinctive peripheral blood immune status at diagnosis, even showing different immune response to treatment. These results reinforce the different biology behind CPR and non-CPR responses.

Immune metabolism in PD-1 blockade-based cancer immunotherapy

Energy metabolism plays an important role in proliferating cells. Recent reports indicate that metabolic regulation or metabolic products can control immune cell differentiation, fate and reactions. Cancer immunotherapy based on blockade of programmed cell death protein 1 (PD-1) has been used worldwide, but a significant fraction of patients remain unresponsive. Therefore, clarifying the mechanisms and overcoming the unresponsiveness are urgent issues. Because cancer immunity consists of interactions between the cancer and host immune cells, there has recently been a focus on the metabolic interactions and/or competition between the tumor and the immune system to address these issues. Cancer cells render their microenvironment immunosuppressive, driving T-cell dysfunction or exhaustion, which is advantageous for cancer cell survival. However, accumulating mechanistic evidence of T-cell and cancer cell metabolism has gradually revealed that controlling the metabolic pathways of either type of cell can overcome T-cell dysfunction and reprogram the metabolic balance in the tumor microenvironment. Here, we summarize the role of immune metabolism in T-cell-based immune surveillance and cancer immune escape. This new concept has boosted the development of combination therapy and predictive biomarkers in cancer immunotherapy with immune checkpoint inhibitors.

Immunological Characteristics of Hyperprogressive Disease in Patients with Non-small Cell Lung Cancer Treated with Anti-PD-1/PD-L1 Abs

Hyperprogressive disease (HPD) is a distinct pattern of progression characterized by acceleration of tumor growth after treatment with anti-PD-1/PD-L1 Abs. However, the immunological characteristics have not been fully elucidated in patients with HPD. We prospectively recruited patients with metastatic non-small cell lung cancer treated with anti-PD-1/PD-L1 Abs between April 2015 and April 2018, and collected peripheral blood before treatment and 7-days post-treatment. HPD was defined as ≥2-fold increase in both tumor growth kinetics and tumor growth rate between pre-treatment and post-treatment. Peripheral blood mononuclear cells were analyzed by multi-color flow cytometry to phenotype the immune cells. Of 115 patients, 19 (16.5%) developed HPD, 52 experienced durable clinical benefit (DCB; partial response or stable disease ≥6 months), and 44 experienced non-hyperprogressive progression (NHPD). Patients with HPD had significantly lower progression-free survival (p<0.001) and overall survival (p<0.001). When peripheral blood immune cells were examined, the pre-treatment frequency of CD39⁺ cells among CD8⁺ T cells was significantly higher in patients with HPD compared to those with NHPD, although it showed borderline significance to predict HPD. Other parameters regarding regulatory T cells or myeloid derived suppressor cells did not significantly differ among patient groups. Our findings suggest high pre-treatment frequency of CD39⁺CD8⁺ T cells might be a characteristic of HPD. Further investigations in a larger cohort are needed to confirm our results and better delineate the immune landscape of HPD.

Complete response to immunotherapy combined with an antiangiogenic agent in multiple hepatic metastases after radical surgery for advanced gallbladder cancer: a case report

Most advanced gallbladder cancers (GBCa) are unresectable or metastatic once diagnosed, and even patients who undergo surgery have a high risk of recurrence and metastasis. Immunotherapy, especially immune checkpoint inhibitors (ICIs), combined with an antiangiogenic agent, is an emerging prospective treatment for GBCa. However, the efficacy and safety of this combination therapy have not yet been investigated. We report the case of a 70-year-old female patient with recurrent metastatic GBCa (stage IVB) after radical surgery. Immunohistochemical examination revealed that 10% of the tumor cells expressed programmed cell death protein-1 (PD-1) and programmed cell death receptor ligand 1 (PD-L1). Whole-exome sequencing showed cancer tissues with a low tumor mutational burden (TMB) and microsatellite stability (MSS). The patient received Camrelizumab (200 mg, every three weeks) and Apatinib (40 mg/d). The clinical and immunological responses were observed, and the patient achieved a complete response after five cycles. This is the first case describing the efficacy and safety of Camrelizumab plus Apatinib in a GBCa patient with weak PD-1 and PD-L1 expression, and low TMB and MSS. The treatment had a tolerable safety profile and a complete response in the patient. Also, we found that the cluster of differentiation (CD)16+CD56+natural killer (NK) cell ratio in peripheral blood was increased after the combined treatment. Immunotherapy with antiangiogenic drugs may be a potential treatment option for patients with recurrent GBC or GBCa.