Transcriptional profiling of melanoma sentinel nodes identify patients with poor outcome and reveal an association of CD30(+) T lymphocytes with progression

Diagnostic and prognostic value of double-negative T cells in colorectal cancer

Objective

To evaluate the T-lymphocyte subset distribution and the diagnostic and prognosis value of double-negative T (DNT) cells in colorectal cancer (CRC).

Methods

This retrospective study compared the T-lymphocyte subsets and DNT of 114 patients with CRC with those of 107 healthy controls (HC). The diagnostic potential of DNT and T-lymphocyte subsets was assessed using the receiver operating characteristic (ROC) curve, and prognostic values were evaluated using the Kaplan-Meier curve and the Cox regression model.

Results

The percentages of CD8+ T cells and DNT cells, and value of carcinoembryonic antigen (CEA), were remarkably higher in patients with CRC than in those with HC, but the ratio of CD4+/CD8+ was decreased. Using ROC curve analysis, DNT cell percentage, CEA, and CD4+/CD8+ ratio all had good diagnostic efficacy, with areas under the curve (AUCs) of 0.865, 0.786 and 0.624, respectively. The combination of DNT cell percentage and CEA had an AUC of 0.905, which was significantly higher than that of any single biomarker (p < 0.05). In univariate analysis, the Tumor Node Metastasis (TNM) clinical stage, CD4+/CD8+ ratio, and DNT cell percentage were significantly associated with overall survival (OS) (p < 0.05). In multivariate analysis, TNM clinical staging (HR = 2.37, 95 % CI: 1.15-4.90), a decreased CD4+/CD8+ ratio (HR = 0.33, 95 % CI: 0.15-0.74), and an increased DNT cell percentage (HR = 2.29, 95 % CI: 1.11-4.73) were independent prognostic factors for CRC.

Conclusion

The percentage of DNT cells may be useful as an evaluation index for CRC diagnosis and prognosis, which was even better when combined with serum CEA.

Double Trouble: Immunotherapy Doublets in Melanoma-Approved and Novel Combinations to Optimize Treatment in Advanced Melanoma

Immune checkpoint inhibitors, particularly anti-PD-1-based immune checkpoint inhibitors, have dramatically improved outcomes for patients with advanced melanoma and are currently deemed a standard of care. Ipilimumab/nivolumab is the first combination of immune checkpoint inhibitors to improve progression-free survival and overall survival in the first-line setting, with durable responses and the longest median overall survival, 72.1 months, of any drug therapy approved for advanced melanoma. However, its use is limited by the high rate of severe (grade 3-4) treatment-related adverse events. More recently, the novel immune checkpoint inhibitor combination of nivolumab/relatlimab (anti-PD-1/anti-LAG3) showed improved progression-free survival compared with nivolumab alone in the first-line setting and was well tolerated; thus, it is likely this combination will be added to the armamentarium as a first-line treatment for advanced melanoma. These changes in the treatment landscape have several treatment implications for decision-making. The choice of first-line systemic drug therapy, and the decision between immune checkpoint inhibitor monotherapy or combination therapy, requires a comprehensive assessment of disease-related factors and patient characteristics. Despite this striking progress, many patients' disease still progresses. Several new agents and therapeutic approaches are under investigation in clinical trials. Intralesional treatments hold promise for accessible metastases, although their broad application in the clinic will be limited. Prognostic and predictive biomarkers, as well as strategies to reduce treatment-related toxicities and overcome resistance, are required and are now the focus of clinical and translational research.

CD3+CD4-CD8- (Double-Negative) T Cells in Inflammation, Immune Disorders and Cancer

The crucial role of CD4⁺ and CD8⁺ T cells in shaping and controlling immune responses during immune disease and cancer development has been well established and used to achieve marked clinical benefits. CD3⁺CD4^-CD8^- double-negative (DN) T cells, although constituting a rare subset of peripheral T cells, are gaining interest for their roles in inflammation, immune disease and cancer. Herein, we comprehensively review the origin, distribution and functions of this unique T cell subgroup. First, we focused on characterizing multifunctional DN T cells in various immune responses. DN regulatory T cells have the capacity to prevent graft-versus-host disease and have therapeutic value for autoimmune disease. T helper-like DN T cells protect against or promote inflammation and virus infection depending on the specific settings and promote certain autoimmune disease. Notably, we clarified the role of DN tumor-infiltrating lymphocytes and outlined the potential for malignant proliferation of DN T cells. Finally, we reviewed the recent advances in the applications of DN T cell-based therapy for cancer. In conclusion, a better understanding of the heterogeneity and functions of DN T cells may help to develop DN T cells as a potential therapeutic tool for inflammation, immune disorders and cancer.

Examining the Relationship between Circulating CD4- CD8- Double-Negative T Cells and Outcomes of Immuno-Checkpoint Inhibitor Therapy-Looking for Biomarkers and Therapeutic Targets in Metastatic Melanoma

Background: The role of circulating CD4−/CD8− double-negative T cells (DNTs) in the immune response to melanoma is poorly understood, as are the effects of checkpoint inhibitors on T cell subpopulations. Methods: We performed a basal and longitudinal assessment of circulating immune cells, including DNTs, in metastatic melanoma patients treated with checkpoint blockade in a single-center cohort, and examined the correlations levels of immune cells with clinical features and therapy outcomes. Results: Sixty-eight patients (48 ipilimumab, 20 PD1 inhibitors) were enrolled in the study. Our analysis indicated that better outcomes were associated with normal LDH, fewer than three metastatic sites, an ECOG performance status of 0, M1a stage, lower WBC and a higher lymphocyte count. The increase in lymphocyte count and decrease of DNTs were significantly associated with the achievement of an overall response. The median value of DNT decreased while the CD4+ and NK cells increased in patients that responded to treatment compare to those who did not respond to treatment. Conclusions: DNT cells change during treatment with checkpoint inhibitors and may be adept at sensing the immune response to melanoma. The complementary variation of DNT cells with respect to CD4+ and other immune actors may improve the reliability of lymphocyte assessment. Further investigation of DNT as a potential target in checkpoint inhibitor resistant melanoma is warranted.

Clinical importance of the expression of CD4+CD8+ T cells in renal cell carcinoma

OBJECTIVE

CD4+CD8+ T cells are expressed in some cancer patients including those with renal cell carcinoma (RCC). However, no reports have mentioned the clinical importance of this expression. We evaluated the expression of CD4+CD8+ T cells in patients with various cancer types to clarify clinical characteristics and prognostic importance significantly correlating with these T cells.

METHODS

Expression of CD4+CD8+ T cells was evaluated using flowcytometry in tissue-infiltrating lymphocytes extracted from 260 cancer tissues including 104 RCC samples. RNA sequencing and characterization and regression (Citrus) was used to determine characteristics. The prognostic importance of CD4+CD8+ T cells was evaluated by Cox regression analysis.

RESULTS

Among eight cancer types, expression of CD4+CD8+ T cells was significantly highest in RCC patients. According to the expression of CD4+CD8+ T cells in adjacent normal tissue-infiltrating lymphocytes, 24 patients (23.1%) were defined as being positive for CD4+CD8+ with an expression higher than 9.29% in RCC patients. Citrus showed CD8+PD-1+TIM-3+CD103- T cells to be a specific subpopulation of CD4+CD8+ T cells. RNA sequencing revealed that CD4+CD8+ T cells had significantly lower diversity than the other T cells and shared most T-cell receptor clones with CD8+ not CD4+ T cells. Expression of CD4+CD8+ T cells was identified as an independent predictor of overall survival (hazard ratio: 0.11, 95% confidence interval: 0.01-0.86, P = 0.035) in multivariate analysis.

CONCLUSIONS

The expression of CD4+CD8+ T cells was significantly up-regulated in RCC patients and correlated significantly with prognostic importance in surgically treated RCC patients.

Identification of differentially expressed genes in lung adenocarcinoma cells using single-cell RNA sequencing not detected using traditional RNA sequencing and microarray

Lung adenocarcinoma (LUAD) is the leading cause of cancer-related deaths worldwide. Traditional RNA sequencing data fails to detect the exact cellular and molecular changes in tumor cells as they make up only a small proportion of tumor tissue. 10× genomics single-cell RNA sequencing (10× scRNA-seq) and gene expression data of LUAD patients was obtained from the Department of Thoracic Surgery, Zhongshan Hospital, Fudan University, ArrayExpress, TCGA, and GEO databases. Differentially expressed genes (DEGs) were identified in LUAD and alveolar cells (DEGs-scRNA-cancer_cell), tumor- and normal tissue-derived cells (DEGs-scRNA-sample), and normal and LUAD patients (DEGs-Bulk). Flow cytometry and qRT-PCR were performed to validate the significantly differentially expressed ligand-receptor pairs. We selected 159,219 cells and 594 samples in the scRNA-seq data and traditional RNA sequencing, respectively. A total of 1042 DEGs-scRNA-cancer_cell, 788 DEGs-scRNA-sample, and 2510 DEGs-Bulk were identified in this study. We also identified 57 DEGs that were only detected in DEGs-scRNA-cancer_cell (only-DEGs-scRNA-cancer_cell). To explore the relationship between only-DEGs-scRNA-cancer_cell and survival in LUAD, 14 and 22 only-DEGs-scRNA-cancer_cell, which were closely related with survival in TCGA and GEO cohorts were identified. Functional enrichment analyses showed these DEGs-scRNA-cancer_cells were mainly related to cell proliferation and immunoregulation. Our study detected and compared DEGs at different levels and revealed genes that may regulate tumor development. Our results provide a potential new protocol to determine the contribution of DEGs to cancer progression and to help identify potential therapeutic targets.

Blocking CD30 on T Cells by a Dual Specific CAR for CD30 and Colon Cancer Antigens Improves the CAR T Cell Response against CD30- Tumors

Chimeric antigen receptor (CAR)-engineered T cells are efficacious in controlling advanced leukemia and lymphoma, however, they fail in the treatment of solid cancer, which is thought to be due to insufficient T cell activation. We revealed that the immune response of CAR T cells with specificity for carcinoembryonic antigen (CEA) was more efficacious against CEA⁺ cancer cells when simultaneously incubated with an anti-CD30 immunotoxin or anti-CD30 CAR T cells, although the targeted cancer cells lack CD30. The same effect was achieved when the anti-CD30 single-chain variable fragment (scFv) was integrated into the extracellular domain of the anti-CEA CAR. Improvement in T cell activation was due to interfering with the T cell CD30-CD30L interaction by the antagonistic anti-CD30 scFv HRS3; an agonistic anti-CD30 scFv or targeting the high-affinity interleukin-2 (IL-2) receptor was not effective. T cells with the anti-CD30/CEA CAR showed superior immunity against established CEA⁺ CD30^- tumors in a mouse model. The concept is broadly applicable since anti-CD30/TAG72 CAR T cells also showed improved elimination of TAG72⁺ CD30^- cancer cells. Taken together, targeting CD30 on CAR T cells by the HRS3 scFv within the anti-tumor CAR improves the redirected immune response against solid tumors.

Computational Immune Monitoring Reveals Abnormal Double-Negative T Cells Present across Human Tumor Types

Advances in single-cell biology have enabled measurements of >40 protein features on millions of immune cells within clinical samples. However, the data analysis steps following cell population identification are susceptible to bias, time-consuming, and challenging to compare across studies. Here, an ensemble of unsupervised tools was developed to evaluate four essential types of immune cell information, incorporate changes over time, and address diverse immune monitoring challenges. The four complementary properties characterized were (i) systemic plasticity, (ii) change in population abundance, (iii) change in signature population features, and (iv) novelty of cellular phenotype. Three systems immune monitoring studies were selected to challenge this ensemble approach. In serial biopsies of melanoma tumors undergoing targeted therapy, the ensemble approach revealed enrichment of double-negative (DN) T cells. Melanoma tumor-resident DN T cells were abnormal and phenotypically distinct from those found in nonmalignant lymphoid tissues, but similar to those found in glioblastoma and renal cell carcinoma. Overall, ensemble systems immune monitoring provided a robust, quantitative view of changes in both the system and cell subsets, allowed for transparent review by human experts, and revealed abnormal immune cells present across multiple human tumor types.

Unique Genes in Tumor-Positive Sentinel Lymph Nodes Associated with Nonsentinel Lymph Node Metastases in Melanoma

BACKGROUND

Current risk assessment tools to estimate the risk of nonsentinel lymph node metastases after completion lymphadenectomy for a positive sentinel lymph node (SLN) biopsy in cutaneous melanoma are based on clinical and pathologic factors. We identified a novel genetic signature that can predict non-SLN metastases in patients with cutaneous melanoma staged with a SLN biopsy.

METHODS

RNA was collected for tumor-positive SLNs in patients staged by SLN biopsy for cutaneous melanoma. All patients with a tumor-positive SLN biopsy underwent completion lymphadenectomy. A 1:10 case:control series of positive and negative non-SLN patients was analyzed by microarray and quantitative RT-PCR. Candidate differentially expressed genes were validated in a 1:3 case:control separate cohort of positive and negative non-SLN patients.

RESULTS

The 1:10 case:control discovery set consisted of 7 positive non-SLN cases matched to 70 negative non-SLN controls. The cases and controls were similar with regards to important clinicopathologic factors, such as gender, primary tumor site, age, ulceration, and thickness. Microarray and RT-PCR identified six potential differentially expressed genes for validation. In the 40-patient separate validation set, 10 positive non-SLN patients were matched to 30 negative non-SLN controls based on gender, ulceration, age, and thickness. Five of the six genes were differentially expressed. The five gene panel identified patients at low (7.1%) and high risk (66.7%) for non-SLN metastases.

CONCLUSIONS

A novel, non-SLN gene score based on differential expressed genes in a tumor-positive SLN can identify patients at high and low risk for non-SLN metastases.

Tumor infiltrating lymphocytes in lymph node metastases of stage III melanoma correspond to response and survival in nine patients treated with ipilimumab at the time of stage IV disease

Prognosis of metastatic melanoma improved with the development of checkpoint inhibitors. The role of tumor infiltrating lymphocytes (TILs) in lymph node metastases of stage III melanoma remains unclear. We retrospectively characterized TILs in primary melanomas and matched lymph node metastases (stage III melanoma) of patients treated with the checkpoint inhibitor ipilimumab. Tumor infiltrating lymphocytes were characterized for CD3, CD4, and CD8 expressions by immunohistochemistry. 4/9 patients (44%) responded to treatment with ipilimumab (1 complete and 2 partial remissions, 1 stable disease). All responders exhibited CD4 and CD8 T-cell infiltration in their lymph node metastases, whereas all non-responders did not show an infiltration of the lymph node metastasis with TILs. The correlation between the presence and absence of TILs in responders vs. non-responders was statistically significant (p = 0.008). Median distant metastases free survival, i.e., progression from stage III to stage IV melanoma, was similar in responders and non-responders (22.1 vs. 19.3 months; p = 0.462). Median progression free and overall survival show a trend in favor of the patients having TIL rich lymph node metastases (6.8 vs. 3.3 months, p = 0.09; and all alive at last follow-up vs. 8.2 months, respectively, p = 0.08). Our data suggest a correlation between the T-cell infiltration of the lymph node metastases in stage III melanoma and the response to ipilimumab once these patients progress to stage IV disease.

β-Catenin in desmoid-type fibromatosis: deep insights into the role of T41A and S45F mutations on protein structure and gene expression

Desmoid‐type fibromatosis (DF) is a rare mesenchymal lesion with high risk of local recurrence. Specific β‐catenin mutations (S45F) appeared to be related to this higher risk compared to T41A‐mutated or wild‐type (WT). We explored the influence of both mutations and WT on structure stability and affinity of β‐catenin for α‐catenin and the pattern of gene expression that may influence DF behavior. Using 33 surgically resected primary DFs harboring T41A (n = 14), S45F (n = 10), or WT (n = 9), we performed a comparative molecular analysis by protein/protein interaction modeling, gene expression by DASL microarrays, human inflammation gene panel, and assessment of immune system‐based biomarkers by immunohistochemistry. Mutated proteins were more stable than WT and formed a weaker complex with α‐catenin. Consensus unsupervised gene clustering revealed the presence of two DF group‐mutated (T41A + S45F) and WT (P = 0.0047). The gene sets ‘Inflammatory‐Defense‐Humoral Immune Response’ and ‘Antigen Binding’ were significantly enriched in T41A. The deregulation of 16 inflammation‐related genes was confirmed. Low numbers of T cells and tumor‐associated macrophages (TAM) infiltrating the tumors and low/absent PD‐1/PD‐L1 expression were also identified. We demonstrated that mutated DFs (T41A or S45F) and WT are two distinct molecular subgroups with regard to β‐catenin stability, α‐catenin affinity, and gene expression profiling. A different inflammation signature characterized the two mutated groups, suggesting mediation either by T41A or by S45F. Finally, all mutated cases showed a low number of TIL and TAM cells and a low or absent expression of PD‐1 and PD‐L1 consistent with β‐catenin activation insensitive to checkpoint blockade.

Presence of immune cells, low tumor proliferation and wild type BRAF mutation status is associated with a favourable clinical outcome in stage III cutaneous melanoma

BACKGROUND

The variable prognosis in stage III cutaneous melanoma is partially due to unknown prognostic factors. Improved prognostic tools are required to define patients with an increased risk of developing metastatic disease who might benefit from adjuvant therapies. The aim was to examine if cellular immune markers in association with tumor proliferation rate and BRAF mutation status have an impact on prognosis in stage III melanoma.

METHODS

We have used two sets of case series with stage III disease: 23 patients with short survival (≤ 13 months) and 19 patients with long survival (≥ 60 months). Lymph node metastases were analyzed for Ki67, CD8 and FOXP3 protein expression using immunohistochemistry. BRAF mutation status was analyzed in a previous study on the same samples.

RESULTS

Low tumor proliferation rate was significantly associated with a better prognosis (p = 0.013). Presence of FOXP3+ T cells was not correlated to adverse clinical outcome. A highly significant trend for a longer survival was found in the presence of an increasing number of markers; CD8+ and FOXP3+ T cells, low tumor proliferation and BRAF wildtype status (p = 0.003). Presence of at least three of these four markers was found to be an independent favorable prognostic factor (OR 19.4, 95% CI 1.9-197, p = 0.012), when adjusting for ulceration and number of lymph node metastases. Proliferation alone remained significant in multivariate analyses (OR 26.1, 95% CI 2.0-344, p = 0.013) but with a wider confidence interval. This panel still remained independent when also adjusting for a previously identified prognostic glycolytic-pigment panel.

CONCLUSIONS

We have demonstrated that presence of immune cells in association with tumor proliferation and BRAF mutation status may further contribute to identify stage III melanoma patients with high risk of relapse.

Targeted agents and immunotherapies: optimizing outcomes in melanoma

Treatment options for patients with metastatic melanoma, and especially BRAF-mutant melanoma, have changed dramatically in the past 5 years, with the FDA approval of eight new therapeutic agents. During this period, the treatment paradigm for BRAF-mutant disease has evolved rapidly: the standard-of-care BRAF-targeted approach has shifted from single-agent BRAF inhibition to combination therapy with a BRAF and a MEK inhibitor. Concurrently, immunotherapy has transitioned from cytokine-based treatment to antibody-mediated blockade of the cytotoxic T-lymphocyte-associated antigen-4 (CTLA-4) and, now, the programmed cell-death protein 1 (PD-1) immune checkpoints. These changes in the treatment landscape have dramatically improved patient outcomes, with the median overall survival of patients with advanced-stage melanoma increasing from approximately 9 months before 2011 to at least 2 years - and probably longer for those with BRAF-V600-mutant disease. Herein, we review the clinical trial data that established the standard-of-care treatment approaches for advanced-stage melanoma. Mechanisms of resistance and biomarkers of response to BRAF-targeted treatments and immunotherapies are discussed, and the contrasting clinical benefits and limitations of these therapies are explored. We summarize the state of the field and outline a rational approach to frontline-treatment selection for each individual patient with BRAF-mutant melanoma.

Systematic evaluation of immune regulation and modulation

Cancer immunotherapies are showing promising clinical results in a variety of malignancies. Monitoring the immune as well as the tumor response following these therapies has led to significant advancements in the field. Moreover, the identification and assessment of both predictive and prognostic biomarkers has become a key component to advancing these therapies. Thus, it is critical to develop systematic approaches to monitor the immune response and to interpret the data obtained from these assays. In order to address these issues and make recommendations to the field, the Society for Immunotherapy of Cancer reconvened the Immune Biomarkers Task Force. As a part of this Task Force, Working Group 3 (WG3) consisting of multidisciplinary experts from industry, academia, and government focused on the systematic assessment of immune regulation and modulation. In this review, the tumor microenvironment, microbiome, bone marrow, and adoptively transferred T cells will be used as examples to discuss the type and timing of sample collection. In addition, potential types of measurements, assays, and analyses will be discussed for each sample. Specifically, these recommendations will focus on the unique collection and assay requirements for the analysis of various samples as well as the high-throughput assays to evaluate potential biomarkers.

microRNA Expression in Sentinel Nodes from Progressing Melanoma Patients Identifies Networks Associated with Dysfunctional Immune Response

Sentinel node biopsy (SNB) is a main staging biomarker in melanoma and is the first lymph node to drain the tumor, thus representing the immunological site where anti-tumor immune dysfunction is established and where potential prognostic immune markers can be identified. Here we analyzed microRNA (miR) profiles in archival tumor-positive SNBs derived from melanoma patients with different outcomes and performed an integrated analysis of transcriptional data to identify deregulated immune signaling networks. Twenty-six miRs were differentially expressed in melanoma-positive SNB samples between patients with disease progression and non-progressing patients, the majority being previously reported in the regulation of immune responses. A significant variation in miR expression levels was confirmed in an independent set of SNB samples. Integrated information from genome-wide transcriptional profiles and in vitro assessment in immune cells led to the identification of miRs associated with the regulation of the TNF receptor superfamily member 8 (TNFRSF8) gene encoding the CD30 receptor, a marker increased in lymphocytes of melanoma patients with progressive disease. These findings indicate that miRs are involved in the regulation of pathways leading to immune dysfunction in the sentinel node and may provide valuable markers for developing prognostic molecular signatures for the identification of stage III melanoma patients at risk of recurrence.

Immunophenotyping of Stage III Melanoma Reveals Parameters Associated with Patient Prognosis

Stage III metastatic melanomas require adequate adjuvant immunotherapy to prevent relapses. Prognostic factors are awaited to optimize the clinical management of these patients. The magnitude of metastatic lymph node invasion and the BRAF(V600) activating mutation have clinical significance. Based on a comprehensive immunophenotyping of 252 parameters per patient in paired blood and metastatic lymph nodes performed in 39 metastatic melanomas, we found that blood markers were as contributive as tumor-infiltrated lymphocyte immunotypes, and parameters associated with lymphocyte exhaustion/suppression showed higher clinical significance than those related to activation or lineage. High frequencies of CD45RA(+)CD4(+) and CD3(-)CD56(-) tumor-infiltrated lymphocytes appear to be independent prognostic factors of short progression-free survival. High NKG2D expression on CD8(+)tumor-infiltrated lymphocytes, low level of regulatory T-cell tumor-infiltrated lymphocytes, and low PD-L1 expression on circulating T cells were retained in the multivariate Cox analysis model to predict prolonged overall survival. Prospective studies are needed to determine whether such immunological markers may guide adjuvant therapies in stage III metastatic melanomas.

Functional Genomics Uncover the Biology behind the Responsiveness of Head and Neck Squamous Cell Cancer Patients to Cetuximab

PURPOSE

To identify the tumor portrait of the minority of head and neck squamous cell carcinoma (HNSCC) patients with recurrent-metastatic (RM) disease who upon treatment with platinum-based chemotherapy plus cetuximab present a long-lasting response.

EXPERIMENTAL DESIGN

The gene expression of pretreatment samples from 40 HNSCC-RM patients, divided in two groups [14 long-progression-free survival (PFS) and 26 short-PFS (median = 19 and 3 months, respectively)], was associated with PFS and was challenged against a dataset from metastatic colon cancer patients treated with cetuximab. For biologic analysis, we performed functional and subtype association using gene set enrichment analysis, associated biology across all currently available HNSCC signatures, and inferred drug sensitivity using data from the Cancer Genomic Project.

RESULTS

The identified genomic profile exhibited a significant predictive value that was essentially confirmed in the single publicly available dataset of cetuximab-treated patients. The main divergence between long- and short-PFS groups was based on developmental/differentiation status. The long-PFS patients are characterized by basal subtype traits such as strong EGFR signaling phenotype and hypoxic differentiation, further validated by the significantly higher association with the hypoxia metagene. The short-PFS patients presented a strong activation of RAS signaling confirmed in an in vitro model of two isogenic HNSCC cell lines sensitive or resistant to cetuximab. The predicted drug sensitivity for all four EGFR inhibitors was higher in long- versus short-PFS patients (P range: <0.0022-1e-07).

CONCLUSIONS

Our data uncover the biology behind response to platinum-based chemotherapy plus cetuximab in RM-HNSCC cancer and may have translational implications improving treatment selection. Clin Cancer Res; 22(15); 3961-70. ©2016 AACRSee related commentary by Chau and Hammerman, p. 3710.

Is sentinel node susceptibility to metastases related to nodal immune modulation?

Sentinel lymph nodes (SLNs), the initial site of regional metastases, directly receive lymph containing immune-modulatory cytokines and tumor cells from primary melanomas. Immune-suppressed SLNs are ideal for studies of tissue susceptibility to metastases. They show reduced antigen-presenting dendritic cells, activated T cells, high endothelial venules, and transvenular immigration of T cells. Tumor-induced immune suppression contributes to establishment of nodal metastases. SLNs may serve as an effective model to study reversal of tumor-induced immune suppression. We reviewed this topic in Nature Reviews of Immunology in 2006. We here summarize the Nature paper and provide additional results from ongoing studies and the recent literature.

Immune checkpoints: Cytotoxic T-lymphocyte antigen 4 and programmed cell death protein 1 in breast cancer surgery

Immune checkpoints refer to a plethora of inhibitory pathways built into the immune system, and recent studies have emphasized the role of these checkpoints in carcinogenesis. The aim of the present study was to evaluate two major immune checkpoints, the cytotoxic T-lymphocyte antigen 4 (CTLA-4) and programmed cell death protein 1 (PD-1), in the serum of 35 patients with stage I and II breast cancer. Serum concentrations of CTLA-4 and PD-1 were measured at three time points: i) Preoperatively; ii) during anesthesia following the harvesting of sentinel nodes (SNs); and iii) 24 h postoperatively. Control samples were obtained from 25 healthy, age-matched females. Assessment of CTLA-4 and PD-1 expression levels was conducted using flow cytometry. A statistically significant difference in PD-1 expression was identified between breast cancer patients preoperatively and healthy controls (26.31±11.87 vs. 12.72±8.15; P<0.0001). In addition, a statistically significant association was found between CTLA-4 and PD-1 levels prior to surgery (P=0.0084). In addition, CTLA-4 expression was associated with age (P=0.0453), with elevated levels of CTLA-4 detected in older breast cancer patients. Higher PD-1 expression levels were observed in T2 tumors compared with T1 tumors prior to surgery and intraoperatively; however, the differences were not statistically significant. Furthermore, a decrease in PD-1 levels was observed subsequent to harvesting SNs with metastasis, but not in SN-negative patients (P=0.05). A negative correlation was also observed between PD-1 expression and progesterone receptor (PR) status following surgery (P=0.024). These results provided a basis for further investigation of immune checkpoints in breast cancer. Breast cancer patients exhibit an altered profile of immune checkpoint markers, with higher concentrations of PD-1 observed in larger, PR-negative tumors.

Characterization of the Microenvironment in Positive and Negative Sentinel Lymph Nodes from Melanoma Patients

Melanomas are aggressive skin tumors characterized by high metastatic potential. Our previous results indicate that Natural Killer (NK) cells may control growth of melanoma. The main defect of blood NK cells was a decreased expression of activating NCR1/NKp46 receptor and a positive correlation of NKp46 expression with disease outcome in stage IV melanoma patients was found. In addition, in stage III melanoma patients, we identified a new subset of mature NK cells in macro-metastatic Lymph nodes (LN). In the present studies, we evaluated the numbers of NK cells infiltrating primary cutaneous melanoma and analyzed immune cell subsets in a series of sentinel lymph nodes (SLN). First, we show that NKp46+ NK cells infiltrate primary cutaneous melanoma. Their numbers were related to age of patients and not to Breslow thickness. Then, a series of patients with tumor-negative or -positive sentinel lymph nodes matched for Breslow thickness of the cutaneous melanoma was constituted. We investigated the distribution of macrophages (CD68), endothelial cells, NK cells, granzyme B positive (GrzB+) cells and CD8+ T cells in the SLN. Negative SLN (SLN-) were characterized by frequent adipose involution and follicular hyperplasia compared to positive SLN (SLN+). High densities of macrophages and endothelial cells (CD34), prominent in SLN+, infiltrate SLN and may reflect a tumor favorable microenvironment. Few but similar numbers of NK and GrzB+ cells were found in SLN- and SLN+: NK cells and GrzB+ cells were not correlated. Numerous CD8+ T cells infiltrated SLN with a trend for higher numbers in SLN-. Moreover, CD8+ T cells and GrzB+ cells correlated in SLN- not in SLN+. We also observed that the numbers of CD8+ T cells negatively correlated with endothelial cells in SLN-. The numbers of NK, GrzB+ or CD8+ T cells had no significant impact on overall survival. However, we found that the 5 year-relapse rate was higher in SLN with higher numbers of NK cells.

Introduction to the role of the immune system in melanoma

The concept of immunosurveillance of cancer has been widely accepted for many years, but only recently have the precise mechanisms of tumor-host immune interactions been revealed. Inflammatory and immune reactions play a role in melanomagenesis, and may contribute to the eradication of tumor as well as potentiating its growth and proliferation. Studies of the role of tumor-immune system interactions are providing insights into the pathogenesis and opportunities for highly effective therapeutic strategies. Some patients, even with advanced disease, are now cured with immunotherapy, and increasing numbers of such cures are likely in future.

Immune cells in the melanoma microenvironment hold information for prediction of the risk of recurrence and response to treatment

Melanoma is an immunogenic tumor and immunotherapy treatment has established an increase in disease-free and overall survival in melanoma patients. However, a complex network of immunosuppressive mechanisms has been demonstrated to occur at the tumor site and in locoregional immune districts, such as sentinel lymph nodes (SLNs). The interplay between tumor cells and the local microenvironment leads to a tumor-driven shaping of the immune response that results in a heterogeneous cellular and molecular composition of tumor infiltrating lymphocytes (TILs). Several studies have reported the potential prognostic value of TILs infiltrating primary tumors and the association of 'immune signature' in SLNs and in melanoma metastases with prognosis and responsiveness to immunotherapeutic approaches. However, a systematic and deeper characterization of the local immunological status of TILs and SLNs is still required to refine melanoma stage classification.

Immune response markers in sentinel nodes may predict melanoma progression

We recently reported that variable expression of immune-response genes distinguishes tumor positive sentinel nodes in melanoma patients with malignant progression from those with non-progressing disease. Our results depict sentinel nodes as sites in which immune functions are associated with metastatic disease and identify CD30 as a host immune-related cancer prognostic marker and potential therapeutic target.