KIR 2D (L1, L3, L4, S4) and KIR 3DL1 protein expression in non-small cell lung cancer

Epigenetics Meets CAR-T-Cell Therapy to Fight Cancer

Based on the impressive success of Car-T-cell therapy in the treatment of hematological malignancies, a broad application for solid tumors also appears promising. However, some important hurdles need to be overcome. One of these is certainly the identification of specific target antigens on cancer cells. Hypomethylation is a characteristic epigenetic aberration in many tumor entities. Genome-wide screenings for consistent DNA hypomethylations in tumors enable the identification of aberrantly upregulated transcripts, which might result in cell surface proteins. Thus, this approach provides a new perspective for the discovery of potential new Car-T-cell target antigens for almost every tumor entity. First, we focus on this approach as a possible treatment for prostate cancer.

EMT-induced immune evasion: connecting the dots from mechanisms to therapy

Epithelial-mesenchymal transition (EMT) is a dynamic program crucial for organismal development and tissue regeneration. Unfortunately, this program is often hijacked by epithelial tumors to facilitate metastasis. Beyond its role in cancer spread, EMT increases cancer cell survival by activating stem cell programs and bypassing apoptotic programs. Importantly, the capacity of EMT to enforce tumor progression by altering the tumor cell phenotype without triggering immune responses opens the intriguing possibility of a mechanistic link between EMT-driven cancers and immune evasion. Indeed, EMT has been acknowledged as a of driver immune evasion, but the mechanisms are still evolving. Here, we review recent insights into the influence of EMT on tumor immune evasion. Specifically, we focus on the mechanistic roles of EMT in immune escape as the basis that may provide a platform for innovative therapeutic approaches in advanced tumors. We summarize promising therapeutic approaches currently in clinical trials and trending preclinical studies aimed at reinvigorating the tumor microenvironment to create immune-permissive conditions that facilitates immune-mediated tumor clearance. We anticipate that this will assist researchers and pharmaceutical companies in understanding how EMT compromises the immune response, potentially paving the way for effective cancer therapies.

The Comparison of Serum Exosome Protein Profile in Diagnosis of NSCLC Patients

A thorough study of the exosomal proteomic cargo may enable the identification of proteins that play an important role in cancer development. The aim of this study was to compare the protein profiles of the serum exosomes derived from non-small lung cancer (NSCLC) patients and healthy volunteers (control) using the high-performance liquid chromatography coupled to mass spectrometry (HPLC-MS) method to identify potentially new diagnostic and/or prognostic protein biomarkers. Proteins exclusively identified in NSCLC and control groups were analyzed using several bioinformatic tools and platforms (FunRich, Vesiclepedia, STRING, and TIMER2.0) to find key protein hubs involved in NSCLC progression and the acquisition of metastatic potential. This analysis revealed 150 NSCLC proteins, which are significantly involved in osmoregulation, cell-cell adhesion, cell motility, and differentiation. Among them, 3 proteins: Interleukin-34 (IL-34), HLA class II histocompatibility antigen, DM alpha chain (HLA-DMA), and HLA class II histocompatibility antigen, DO beta chain (HLA-DOB) were shown to be significantly involved in the cancer-associated fibroblasts (CAFs) and tumor-associated macrophages (TAMs) infiltration processes. Additionally, detected proteins were analyzed according to the presence of lymph node metastasis, showing that differences in frequency of detection of protein FAM166B, killer cell immunoglobulin-like receptor 2DL1, and olfactory receptor 52R1 correlate with the N feature according to the TNM Classification of Malignant Tumors. These results prove their involvement in NSCLC lymph node spread and metastasis. However, this study requires further investigation.

Unpacking the Complexity of Epithelial Plasticity: From Master Regulator Transcription Factors to Non-Coding RNAs

Cellular plasticity in cancer enables adaptation to selective pressures and stress imposed by the tumor microenvironment. This plasticity facilitates the remodeling of cancer cell phenotype and function (such as tumor stemness, metastasis, chemo/radio resistance), and the reprogramming of the surrounding tumor microenvironment to enable immune evasion. Epithelial plasticity is one form of cellular plasticity, which is intrinsically linked with epithelial-mesenchymal transition (EMT). Traditionally, EMT has been regarded as a binary state. Yet, increasing evidence suggests that EMT involves a spectrum of quasi-epithelial and quasi-mesenchymal phenotypes governed by complex interactions between cellular metabolism, transcriptome regulation, and epigenetic mechanisms. Herein, we review the complex cross-talk between the different layers of epithelial plasticity in cancer, encompassing the core layer of transcription factors, their interacting epigenetic modifiers and non-coding RNAs, and the manipulation of cancer immunogenicity in transitioning between epithelial and mesenchymal states. In examining these factors, we provide insights into promising therapeutic avenues and potential anti-cancer targets.

Consistent DNA Hypomethylations in Prostate Cancer

With approximately 1.4 million men annually diagnosed with prostate cancer (PCa) worldwide, PCa remains a dreaded threat to life and source of devastating morbidity. In recent decades, a significant decrease in age-specific PCa mortality has been achieved by increasing prostate-specific antigen (PSA) screening and improving treatments. Nevertheless, upcoming, augmented recommendations against PSA screening underline an escalating disproportion between the benefit and harm of current diagnosis/prognosis and application of radical treatment standards. Undoubtedly, new potent diagnostic and prognostic tools are urgently needed to alleviate this tensed situation. They should allow a more reliable early assessment of the upcoming threat, in order to enable applying timely adjusted and personalized therapy and monitoring. Here, we present a basic study on an epigenetic screening approach by Methylated DNA Immunoprecipitation (MeDIP). We identified genes associated with hypomethylated CpG islands in three PCa sample cohorts. By adjusting our computational biology analyses to focus on single CpG-enriched 60-nucleotide-long DNA probes, we revealed numerous consistently differential methylated DNA segments in PCa. They were associated among other genes with NOTCH3, CDK2AP1, KLK4, and ADAM15. These can be used for early discrimination, and might contribute to a new epigenetic tumor classification system of PCa. Our analysis shows that we can dissect short, differential methylated CpG-rich DNA fragments and combinations of them that are consistently present in all tumors. We name them tumor cell-specific differential methylated CpG dinucleotide signatures (TUMS).

Underlying mechanisms of evasion from NK cells as rational for improvement of NK cell-based immunotherapies

Natural killer (NK) cells belong to the family of innate immune cells with the capacity to recognize and kill tumor cells. Different phenotypes and functional properties of NK cells have been described in tumor patients, which could be shaped by the tumor microenvironment. The discovery of HLA class I-specific inhibitory receptors controlling NK cell activity paved the way to the fundamental concept of modulating immune responses that are regulated by an array of inhibitory receptors, and emphasized the importance to explore the potential of NK cells in cancer therapy. Although a whole range of NK cell-based approaches are currently being developed, there are still major challenges that need to be overcome for improved efficacy of these therapies. These include escape of tumor cells from NK cell recognition due to their expression of inhibitory molecules, immune suppressive signals of NK cells, reduced NK cell infiltration of tumors, an immune suppressive micromilieu and limited in vivo persistence of NK cells. Therefore, this review provides an overview about the NK cell biology, alterations of NK cell activities, changes in tumor cells and the tumor microenvironment contributing to immune escape or immune surveillance by NK cells and their underlying molecular mechanisms as well as the current status and novel aspects of NK cell-based therapeutic strategies including their genetic engineering and their combination with conventional treatment options to overcome tumor-mediated evasion strategies and improve therapy efficacy.

KIR-HLA Functional Repertoire Influences Trastuzumab Efficiency in Patients With HER2-Positive Breast Cancer

Trastuzumab induced a high rate of pathological Complete Response (pCR) in patients affected by locally advanced HER2-positive Breast Cancer (HER2-BC), by exploiting immune-mediated mechanisms as Antibody-Dependent Cell Cytotoxicity (ADCC) involving Natural Killer (NK) cells. Host's immune genetics could influence the response to therapy, through the expression of variants that characterize NK receptors involved in ADCC effectiveness. Killer cell immunoglobin-like receptors (KIRs) modulate NK cell activity through their binding to class-I Human Leukocyte Antigens (HLA). The impact of the KIR/HLA repertoire in HER2-BC is under study. We characterized KIR genotypes of 36 patients with locally advanced HER2-BC treated with neoadjuvant chemotherapy including trastuzumab. We monitored pCR achievement before surgery and Disease-Free Survival (DFS) and Overall Survival (OS) after adjuvant therapy. HLA, and Fc gamma receptor IIIa (FcγR3A) and IIa (FcγR2A) were genotyped through targeted PCR and Sanger sequencing in 35/36 patients. The KIR-HLA combinations were then described as functional haplotypes and divided in two main categories as inhibitory tel A and stimulatory tel B. Trastuzumab-dependent ADCC activity was monitored with an in vitro assay using a HER2-BC model and patients' NK cells.We observed a higher frequency of KIR activators in patients who achieved a pCR compared to partial responders. During the study of functional haplotypes, individuals carrying a tel B haplotype showed greater ADCC efficiency than tel A cases. In subjects with the tel A haplotype the presence of the favorite V allele in FcγR3A receptor improved their low ADCC levels. Regardless of the haplotypes detected, the presence of KIR3DL2/HLA-A03 or A11 was always associated with the FcγR3A V allele, and therefore correlated with greater ADCC efficiency. However, this particular KIR receptor appeared to harm DFS and OS. Indeed, patients with tel B haplotype without KIR3DL2/HLA-A03 or A11 showed a better outcome. Our data, although preliminary, suggested a potential predictive role for KIR haplotype tel B, in identifying patients who achieve a pCR after neoadjuvant treatment with trastuzumab, and supported a negative prognostic impact of KIR3DL2/HLA-A03 or A11 in the adjuvant setting.

Blockade of novel immune checkpoints and new therapeutic combinations to boost antitumor immunity

Immunotherapy has emerged as a promising strategy for boosting antitumoral immunity. Blockade of immune checkpoints (ICs), which regulate the activity of cytotoxic T lymphocytes (CTLs) and natural killer (NK) cells has proven clinical benefits. Antibodies targeting CTLA-4, PD-1, and PD-L1 are IC-blockade drugs approved for the treatment of various solid and hematological malignancies. However, a large subset of patients does not respond to current anti-IC immunotherapy. An integrative understanding of tumor-immune infiltrate, and IC expression and function in immune cell populations is fundamental to the design of effective therapies. The simultaneous blockade of newly identified ICs, as well as of previously described ICs, could improve antitumor response. We review the potential for novel combinatory blockade strategies as antitumoral therapy, and their effects on immune cells expressing the targeted ICs. Preclinical evidence and clinical trials involving the blockade of the various ICs are reported. We finally discuss the rationale of IC co-blockade strategy with respect to its downstream signaling in order to improve effective antitumoral immunity and prevent an increased risk of immune-related adverse events (irAEs).

KIR Receptors as Key Regulators of NK Cells Activity in Health and Disease

Natural killer (NK) cells are part of the cellular immune response. They target mainly cancer and virally infected cells. To a high extent cytotoxic activity of NK cells is regulated inter alia by signals from killer immunoglobulin-like receptors (KIR). The major histocompatibility complex (MHC) class I molecules are important ligands for KIR receptors. Binding of ligands (such as MHC I) to the KIR receptors has the important role in solid organ or hematopoietic cell transplantation. Of note, the understanding of the relationship between KIR and MHC receptors may contribute to the improvement of transplant results. Donor-recipient matching, which also includes the KIR typing, may improve monitoring, individualize the treatment and allow for predicting possible effects after transplantation, such as the graft-versus-leukemia effect (GvL) or viral re-infection. There are also less evident implications of KIR/MHC matching, such as with pregnancy and cancer. In this review, we present the most relevant literature reports on the importance of the KIR/MHC relationship on NK cell activity and hematopoietic stem cell transplantation (HSCT)/solid organ transplantation (SOT) effects, the risk of allograft rejection, protection against post-transplant cytomegalovirus (CMV) infection, pregnancy complications, cancer and adoptive therapy with NK cells.

Artificial intelligence-based analysis for immunohistochemistry staining of immune checkpoints to predict resected non-small cell lung cancer survival and relapse

Background

Conventional analysis of single-plex chromogenic immunohistochemistry (IHC) focused on quantitative but spatial analysis. How immune checkpoints localization related to non-small cell lung cancer (NSCLC) prognosis remained unclear.

Methods

Here, we analyzed ten immune checkpoints on 1,859 tumor microarrays (TMAs) from 121 NSCLC patients and recruited an external cohort of 30 NSCLC patients with 214 whole-slide IHC. EfficientUnet was applied to segment tumor cells (TCs) and tumor-infiltrating lymphocytes (TILs), while ResNet was performed to extract prognostic features from IHC images.

Results

The features of galectin-9, OX40, OX40L, KIR2D, and KIR3D played an un-negatable contribution to overall survival (OS) and relapse-free survival (RFS) in the internal cohort, validated in public databases (GEPIA, HPA, and STRING). The IC-Score and Res-Score were two predictive models established by EfficientUnet and ResNet. Based on the IC-Score, Res-Score, and clinical features, the integrated score presented the highest AUC for OS and RFS, which could achieve 0.9 and 0.85 in the internal testing cohort. The robustness of Res-Score was validated in the external cohort (AUC: 0.80–0.87 for OS, and 0.83–0.94 for RFS). Additionally, the neutrophil-to-lymphocyte ratio (NLR) combined with the PD-1/PD-L1 signature established by EfficientUnet can be a predictor for RFS in the external cohort.

Conclusions

Overall, we established a reliable model to risk-stratify relapse and death in NSCLC with a generalization ability, which provided a convenient approach to spatial analysis of single-plex chromogenic IHC.

Application of a classifier combining bronchial transcriptomics and chest computed tomography features facilitates the diagnostic evaluation of lung cancer in smokers and nonsmokers

Lung cancer screening by computed tomography (CT) reduces mortality but exhibited high false-positive rates. We established a diagnostic classifier combining chest CT features with bronchial transcriptomics. Patients with CT-detected suspected lung cancer were enrolled. The sample collected by bronchial brushing was used for RNA sequencing. The e1071 and pROC packages in R software was applied to build the model. Eventually, a total of 283 patients, including 183 with lung cancer and 100 with benign lesions, were included into final analysis. When incorporating transcriptomic data with radiological characteristics, the advanced model yielded 0.903 AUC with 81.1% NPV. Moreover, the classifier performed well regardless of lesion size, location, stage, histologic type or smoking status. Pathway analysis showed enhanced epithelial differentiation, tumor metastasis, and impaired immunity were predominant in smokers with cancer, whereas tumorigenesis played a central role in nonsmokers with cancer. Apoptosis and oxidative stress contributed critically in metastatic lung cancer; by contrast, immune dysfunction was pivotal in locally advanced lung cancer. Collectively, we devised a minimal-to-noninvasive, efficient diagnostic classifier for smokers and nonsmokers with lung cancer, which provides evidence for different mechanisms of cancer development and metastasis associated with smoking. A negative classifier result will help the physician make conservative diagnostic decisions.

Emerging immunotherapy targets in lung cancer

Immunotherapy has become the mainstay for lung cancer treatment, providing sustained therapeutic responses and improved prognosis compared with those obtained with surgery, chemotherapy, radiotherapy, and targeted therapy. It has the potential for anti-tumor treatment and killing tumor cells by activating human immunity and has moved the targets of anti-cancer therapy from malignant tumor cells to immune cell subsets. Two kinds of immune checkpoints, cytotoxic T-lymphocyte-associated antigen 4 (CTLA-4) and programmed death-1 (PD-1)/programmed death ligand 1 (PD-L1), are the main targets of current immunotherapy in lung cancer. Despite the successful outcomes achieved by immune checkpoint inhibitors, a small portion of lung cancer patients remain unresponsive to checkpoint immunotherapy or may ultimately become resistant to these agents as a result of the complex immune modulatory network in the tumor microenvironment. Therefore, it is imperative to exploit novel immunotherapy targets to further expand the proportion of patients benefiting from immunotherapy. This review summarizes the molecular features, biological function, and clinical significance of several novel checkpoints that have important roles in lung cancer immune responses beyond the CTLA-4 and PD-1/PD-L1 axes, including the markers of co-inhibitory and co-stimulatory T lymphocyte pathways and inhibitory markers of macrophages and natural killer cells.

Curative efficacy might be an early predictor of prognosis in patients with small cell lung cancer treated with 2 cycles of platinum-based first-line chemotherapy

BACKGROUND

Platinum-based chemotherapy remains the essential therapy for small cell lung cancer (SCLC). Here, we conducted a statistical analysis to explore whether the curative efficacy of 2-cycle platinum-based chemotherapy can predict the survival of patients with SCLC.

METHODS

Fifty-six SCLC patients who had each received 2 cycles of platinum-based chemotherapy were enrolled. The curative efficacy of the chemotherapy was evaluated, mainly by chest computed tomography, and the treatment response was categorized according to the Response Evaluation Criteria in Solid Tumors (RECIST) 1.1. Patients were continuously followed up for progression-free survival (PFS) and overall survival. The 55 patients were separated into 2 groups by the curative efficacy of the 2-cycle first-line platinum-based chemotherapy. All statistical analyses were performed with SPSS software (version 17.0; SPSS, Inc.; Chicago, IL, USA).

RESULTS

Patients who responded to 2-cycle chemotherapy (partial response, PR) had significantly better survival than others who did not (stable disease, SD or progressive disease, PD). The median progression-free survival (mPFS) in the PR group was 6.330 months, which was significantly longer than the 2.870 months seen in SD+PD group (95% CI: 4.631-8.029 vs. 0.000-5.790, P=0.022). The median overall survival (mOS) was 10.870 months in the PR group, which was remarkably longer than the 8.970 months observed in the SD+PD group (95% CI: 9.546-12.194 vs. 6.517-11.423, P=0.028). Curative efficacy had no correlation with clinical features.

CONCLUSIONS

The curative efficacy of 2-cycle first-line platinum-based chemotherapy was significantly correlated with PFS and OS, and showed prognostic value in SCLC patients. Patients who were sensitive to chemotherapy had superior survival to those who were chemotherapy insensitive.

CD137, an attractive candidate for the immunotherapy of lung cancer

Immunotherapy has become a hotspot in cancer therapy in recent years. Several immune checkpoints inhibitors have been used to treat lung cancer. CD137 is a kind of costimulatory molecule that mediates T cell activation, which regulates the activity of immune cells in a variety of physiological and pathological processes. Targeting CD137 or its ligand (CD137L) has been studied, aiming to enhance anticancer immune responses. Accumulating studies show that anti-CD137 mAbs alone or combined with other drugs have bright antitumor prospects. In the following, we reviewed the biology of CD137, the antitumor effects of anti-CD137 Ab monotherapy and the combined therapy in lung cancer.

Current progress in NK cell biology and NK cell-based cancer immunotherapy

A better understanding of the complex interactions between the immune system and tumour cells from different origins has opened the possibility to design novel procedures of antitumoral immunotherapy. One of these novel approaches is based on the use of autologous or allogeneic natural killer (NK) cells to treat cancer. In the last decade, different strategies to activate NK cells and their use in adoptive NK cell-based therapy have been established. Although NK cells are often considered as a uniform cell population, several phenotypic and functionally distinct NK cells subsets exist in healthy individuals, that are differentially affected by ageing or by apparently innocuous viruses such as cytomegalovirus (CMV). In addition, further alterations in the expression of activating and inhibitory receptors are found in NK cells from cancer patients, likely because of their interaction with tumour cells. Thus, NK cells represent a promising strategy for adoptive immunotherapy of cancer already tested in phase 1/2 clinical trials. However, the existence of NK cell subpopulations expressing different patterns of activating and inhibitory receptors and different functional capacities, that can be found to be altered not only in cancer patients but also in healthy individuals stratified by age or CMV infection, makes necessary a personalized definition of the procedures used in the selection, expansion, and activation of the relevant NK cell subsets to be successfully used in NK cell-based immunotherapy.

Killer immunoglobulin-like receptors/human leukocyte antigen class-I, a crucial immune pathway in cancer

Natural killer cells (NK cells) play a crucial role in tumor immunity. The function of the NK cells is regulated by various receptors expressed on the surface. Among them, the killer immunoglobulin-like receptor (KIR) is one of the most important. The ligand of KIR is major histocompatibility complex class-I (MHC class-I), which is also called human leukocyte antigen class-I (HLA class-I). The combination of HLA class-I and inhibitory KIRs could inhibit NK cells and induce autoimmune tolerance. Inhibitory KIRs were highly expressed on malignant tumor patients, which were related to poor prognosis. KIR/HLA class-I pathway affected the clinical outcomes of cancer through several mechanisms, and inhibitory KIRs could be an ideal target of immunotherapy strategy.

Does selected immunological panel possess the value of predicting the prognosis of early-stage resectable non-small cell lung cancer?

Background

The immune status in the tumor micro-environment of lung cancer is highly informative, and expression status of some biomarkers in the tumor micro-environment may have deep connected statistical characteristics which could indicate immune status and predict related clinical outcomes. In this study, a panel of 9 immune biomarkers are selected for their possible predictive value of clinical outcomes in early-stage resectable non-small cell lung cancer (NSCLC).

Methods

We introduced a new way of interpreting the expression of Immunohistochemistry-based biomarkers in predicting the prognosis of patients. Immunohistochemistry were performed on surgical samples from 139 patients with NSCLC. Cox regression and subgroup analysis were conducted for the screening of biomarkers that were significant in survival and prognosis. Afterwards, Principle Component Analysis was conducted on screened biomarkers in order to extract characteristic root, which were utilized by an Artificial Neuron Network (ANN) for the prediction of clinical outcomes.

Results

Six out of 9 biomarkers were considered significant and were selected for the data analysis. The KMO-Bartlett's Sphericity test was valid (0.658>0.5, P=0.0001). The principle component regression results indicated that the survival was associated with the principle component Z4 (Y=0.316×Z4+2.298, R=0.189, P=0.026). Also, regression-free survival was associated with the principle component Z4 and Z2 (Y=0.314×Z4+0.255×Z2+2.061, R=0.249, P=0.013). Principle components ranking (PCrank) was calculated and after the determination of a cutoff of 0.2, the intergroup comparison of subgrouphigh (PCrank value above 0.2) and subgrouplow (PCrank value below 0.2) was significant in overall survival (OS) (P=0.025). A database search validated our results. Afterwards, the ANN model successfully predicted the clinical outcome, with accuracies of 94.1% and 96.2% respectively in models 1 and 2.

Conclusions

The selected immunological panels have promising potential for predicting the prognosis of resectable NSCLC.

Combining immunotherapies to treat non-small cell lung cancer

Introduction: In recent years, immunotherapy has become an integral part of the treatment of many cancers, including non-small cell lung cancer (NSCLC). Precious therapeutic weapons impacting survival are monoclonal antibodies directed against the programmed death protein-1 (PD-1)/programmed death ligand-1 (PD-L1) immune checkpoint. Areas covered: Unfortunately, not all patients treated with checkpoint inhibitors have durable clinical responses. However, a better understanding of the complexity of interactions between the immune system and cancer, the latter capable of adopting evasion mechanisms, indicates different opportunities to enhance anti-tumor immunity. Expert opinion: In this paper, we review multiple strategies of combining immunotherapies that exploit not only additional immune checkpoint receptors and ligands but also other synergistic approaches such as vaccines or indoleamine 2,3-dioxygenase (IDO) inhibitors with the potential to extend the number of NSCLC patients achieving successful outcomes.

Cancer stem cell immunology and immunotherapy: Harnessing the immune system against cancer's source

Despite recent advances in diagnosis and therapy having improved cancer outcome, many patients still do not respond to treatments, resulting in the progression or relapse of the disease, eventually impairing survival expectations. The limited efficacy of therapy is often attributable to its inability to affect cancer stem cells (CSCs), a small population of cells resistant to current radio- and chemo-therapies. CSCs are characterized by self-renewal and tumor-initiating capabilities, and function as a reservoir for the local and distant recurrence of the disease. Therefore, new therapeutic approaches able to effectively target and deplete CSCs are urgently needed. Immunotherapy is facing a renewed interest for its potential in cancer treatment, and the possibility of harnessing the immune system to target CSCs is being addressed by a new exciting research field. In this chapter, we discuss the cancer stem cell model and illustrate CSC biological and molecular properties, critically addressing theoretical and practical issues linked with their definition and study. We then review the existing literature regarding the immunological properties of CSCs and the complex interplay occurring between CSCs and immune cells. Finally, we present up-to-date studies on CSC immunotargeting and its potential future perspective. In conclusion, understanding the interplay between CSC biology and tumor immunology will provide a deeper understanding of the mechanisms that regulate CSC immunological properties. This will contribute to the design of new CSC-directed immunotherapeutic strategies with the potential of strongly improving cancer outcomes.

Combination of KIR2DS4 and FcγRIIa polymorphisms predicts the response to cetuximab in KRAS mutant metastatic colorectal cancer

Cetuximab is a standard-of-care treatment for RAS wild-type metastatic colorectal cancer (mCRC) but not for those harbor a KRAS mutation since MAPK pathway is constitutively activated. Nevertheless, cetuximab also exerts its effect by its immunomodulatory activity despite the presence of RAS mutation. The aim of this study was to determine the impact of polymorphism FcγRIIIa V158F and killer immunoglobulin-like receptor (KIR) genes on the outcome of mCRC patients with KRAS mutations treated with cetuximab. This multicenter Phase II clinical trial included 70 mCRC patients with KRAS mutated. We found KIR2DS4 gene was significantly associated with OS (HR 2.27; 95% CI, 1.08–4.77; P = 0.03). In non-functional receptor homozygotes the median OS was 2.6 months longer than in carriers of one copy of full receptor. Multivariate analysis confirmed KIR2DS4 as a favorable prognostic marker for OS (HR 6.71) in mCRC patients with KRAS mutation treated with cetuximab. These data support the potential therapeutic of cetuximab in KRAS mutated mCRC carrying non-functional receptor KIR2DS4 since these patients significantly prolong their OS even after heavily treatment. KIR2DS4 typing could be used as predictive marker for identifying RAS mutated patients that could benefit from combination approaches of anti-EGFR monoclonal antibodies and other immunotherapies to overcome the resistance mediated by mutation in RAS.

The combination of anti-KIR monoclonal antibodies with anti-PD-1/PD-L1 monoclonal antibodies could be a critical breakthrough in overcoming tumor immune escape in NSCLC

Background

The anti-programmed death-1 (PD-1)/programmed death ligand-1 (PD-L1) monoclonal antibody has a good effect in the treatment of non-small cell lung cancer (NSCLC), but not all PD-1/PD-L1 positive patients can get benefit from it. Compensatory expression of other immune checkpoints may be correlated with the poor efficacy of anti-PD-1/PD-L1 monoclonal antibodies. The inhibitory human leukocyte antigen (HLA)/killer cell Ig-like receptor (KIR) can effectively block the killing effect of natural killer (NK) cells on tumors. Our previous studies have confirmed that high expression of KIR was correlated with poor prognosis of NSCLC. Inhibitory KIR expression was positively correlated with the expression of PD-1.

Methods

The expressions of KIR 2D (L1, L3, L4, S4) (BC032422/ADQ31987/NP_002246/NP_036446, Abcam) and PD-1 (NAT 105, Cell marque) proteins was assessed by immunohistochemistry.

Results

The expression of inhibitory KIR in tumor cells or tumor infiltrating lymphocytes (TILs) is associated with PD-1 expression. Among PD-1 positive patients, 76.3% were KIR 2D (L1, L3, L4, S4) positive on tumor cells, and 74.6% were KIR 2D (L1, L3, L4, S4) positive on TILs. We compared the expression of inhibitory KIR before and after treatment with nivolumab in 11 patients with NSCLC. We found that five (45.5%) patients had positive expression of inhibitory KIR in tumor tissue after being treated with anti-PD-1 monoclonal antibodies, two of whom exhibited a significant increase in expression of inhibitory KIR, and three showed no change.

Conclusions

PD-1 expression was correlated with KIR 2D (L1, L3, L4, S4) on tumor cells or TILs. The resistance to anti-PD-1 monoclonal antibody treatment might be related to KIR. The inhibitory HLA/KIR could combine with the PD-1/PD-L1 signaling pathway negatively regulating NSCLC tumor immunity.

Expression and function of immune ligand-receptor pairs in NK cells and cancer stem cells: therapeutic implications

BACKGROUND

The interplay between the immune system and cancer cells has come to the forefront of cancer therapeutics, with novel immune blockade inhibitors being approved for the treatment of an increasing list of cancers. However, the majority of cancer patients still display or develop resistance to these promising drugs. It is possible that cancer stem cells (CSCs) are contributing to this therapeutic resistance. Although CSCs usually represent a small percentage of the total number of cancer cells, they are endowed with the ability of self-renewal and to produce differentiated progeny. Additionally, they have shown the capacity to establish tumors after transplantation to animals, even in small numbers. CSCs have also been found to be resistant to various anti-cancer therapies, including chemotherapy, radiation therapy and, more recently, immunotherapy. This is true despite the sensitivity of CSCs to lysis in vitro by natural killer (NK) cells, the main effector cells of the innate immune system. In this paper the expression of ligands specific for NK cells on CSCs, the intracellular network responsible for the expression of the NK cytotoxicity receptors, and the status of activation of NK cells in the tumor micro-environment are reviewed. The aim of this review is to highlight potential strategies for overcoming CSC immune resistance, thereby enhancing the efficacy of current and future anti-cancer therapies.

THERAPEUTIC IMPLICATIONS

NK cell activation in the tumor micro-environment through drugs neutralizing inhibitory immune receptors, and combined with other drugs harnessing the potential of the adaptive immune system, could be the most effective approach for attacking both stem cell and non-stem cell cancer populations.

New strategies in immunotherapy for lung cancer: beyond PD-1/PD-L1

Immunotherapy has significantly altered the treatment landscape for many cancers, including non-small cell lung cancer (NSCLC). Currently approved immuno-oncology agents for lung cancer are aimed at the reversal of immune checkpoints, programmed death protein-1 (PD-1) and programmed death ligand-1 (PD-L1). Although responses to checkpoint inhibitors are encouraging, and in some cases durable, these successes are not universal among all treated patients. In order to optimize our treatment approach utilizing immunotherapy, we must better understand the interaction between cancer and the immune system and evasion mechanisms. In this review, we will provide an overview of the immune system and cancer, and review novel therapies that promote tumor antigen release for immune system detection, activate the effector T-cell response, and reverse inhibitory antitumor signals.

Understanding the checkpoint blockade in lung cancer immunotherapy

Immunotherapies have changed the treatment strategy of some types of tumor including melanoma and, more recently, non-small-cell lung cancer (NSCLC). Immune checkpoints are crucial for the maintenance of self-tolerance and it is known that some tumors use checkpoint systems to evade antitumor immune response. The treatment of advanced NSCLC by immune-checkpoint blockade targeting the programmed cell death protein-1 (PD1/PDL1) and cytotoxic T-lymphocyte antigen 4 (CTLA4) pathways has led to significant clinical benefit either as monotherapy or in combination therapy. Moreover, checkpoint receptors such as lymphocyte activation gene 3 protein (LAG3), T-cell immunoglobulin mucin domain 3 (TIM3) and killer immunoglobulin-like receptors (KIRs) are also being investigated as potential immunotherapeutic targets. This review focuses on the mechanisms of action of the main checkpoint inhibitors in lung cancer and presents the most relevant results from preclinical and clinical studies on immune-based treatments.