High numbers of differentiated effector CD4 T cells are found in patients with cancer and correlate with clinical response after neoadjuvant therapy of breast cancer

Divergent local and systemic antitumor response in primary uveal melanomas

Uveal melanoma (UM) is the most common cancer of the eye. The loss of chromosome 3 (M3) is associated with a high risk of metastases. M3 tumors are more infiltrated by T-lymphocytes than low-risk disomic-3 (D3) tumors, contrasting with other tumor types in which T cell infiltration correlates with better prognosis. Whether these T cells represent an antitumor response and how these T cells would be primed in the eye are both unknown. Herein, we characterized the T cells infiltrating primary UMs. CD8+ and Treg cells were more abundant in M3 than in D3 tumors. CD39+PD-1+CD8+ T cells were enriched in M3 tumors, suggesting specific responses to tumor antigen (Ag) as confirmed using HLA-A2:Melan-A tetramers. scRNAseq-VDJ analysis of T cells evidenced high numbers of proliferating CD39+PD1+CD8+ clonal expansions, suggesting in situ antitumor Ag responses. TCRseq and tumor-Ag tetramer staining characterized the recirculation pattern of the antitumor responses in M3 and D3 tumors. Thus, tumor-Ag responses occur in localized UMs, raising the question of the priming mechanisms in the absence of known lymphatic drainage.

Association of body mass index and inflammatory dietary pattern with breast cancer pathologic and genomic immunophenotype in the nurses' health study

BACKGROUND

Breast tumor immune infiltration is clearly associated with improved treatment response and outcomes in breast cancer. However, modifiable patient factors associated with breast cancer immune infiltrates are poorly understood. The Nurses' Health Study (NHS) offers a unique cohort to study immune gene expression in tumor and adjacent normal breast tissue, immune cell-specific immunohistochemistry (IHC), and patient exposures. We evaluated the association of body mass index (BMI) change since age 18, physical activity, and the empirical dietary inflammatory pattern (EDIP) score, all implicated in systemic inflammation, with immune cell-specific expression scores.

METHODS

This population-based, prospective observational study evaluated 882 NHS and NHSII participants diagnosed with invasive breast cancer with detailed exposure and gene expression data. Of these, 262 women (training cohort) had breast tumor IHC for four classic immune cell markers (CD8, CD4, CD20, and CD163). Four immune cell-specific scores were derived via lasso regression using 105 published immune expression signatures' association with IHC. In the remaining 620 patient evaluation cohort, we evaluated association of each immune cell-specific score as outcomes, with BMI change since age 18, physical activity, and EDIP score as predictors, using multivariable-adjusted linear regression.

RESULTS

Among women with paired expression/IHC data from breast tumor tissue, we identified robust correlation between novel immune cell-specific expression scores and IHC. BMI change since age 18 was positively associated with CD4+ (β = 0.16; p = 0.009), and CD163 novel immune scores (β = 0.14; p = 0.04) in multivariable analyses. In other words, for each 10 unit (kg/m2) increase in BMI, the percentage of cells positive for CD4 and CD163 increased 1.6% and 1.4%, respectively. Neither physical activity nor EDIP was significantly associated with any immune cell-specific expression score in multivariable analyses.

CONCLUSIONS

BMI change since age 18 was positively associated with novel CD4+ and CD163+ cell scores in breast cancer, supporting further study of the effect of modifiable factors like weight gain on the immune microenvironment.

Strobilanthes crispus elicits anti-tumor immunogenicity in in vitro and in vivo metastatic breast carcinoma

Plant-based anticancer agents have the potential to stimulate the immune system to act against cancer cells. A standardized bioactive subfraction of the Malaysian herb, Strobilanthes crispus (L.) Blume (S. crispus) termed F3, demonstrates strong anticancer effects in both in vitro and in vivo models. The anticancer effects might be attributable to its immunomodulatory properties as S. crispus has been traditionally used to enhance the immune system. The current study examined whether F3 could stimulate anti-tumorigenic immunogenicity against 4T1 cells in vitro and in 4T1 cell-induced mammary carcinoma mouse model. We observed that F3 induced significant increase in MHC class I and class II molecules. CD4+, CD8+ and IL-2+ (p<0.05 for all) cells infiltration was also significantly increased in the breast tumor microenvironment of F3-treated mice compared with the tumors of untreated mice. The number of CD68+ macrophages was significantly lower in F3-treated mice. We conclude that the antitumor and antimetastatic effects of S. crispus involve strong infiltration of T cells in breast cancer potentially through increased tumor antigen presentation via MHC proteins, as well as reduction of infiltrating tumor-associated macrophages.

A simple CD4+ T cells to FIB-4 ratio for evaluating prognosis of BCLC-B hepatocellular carcinoma: a retrospective cohort study

Introduction

Immunotherapy has become a new therapy for advanced hepatocellular carcinoma (HCC); however, its treatment results are considerably different. CD4+ T cells (CD4+) are the key to immunotherapy, but patients with HCC that have low CD4+ are rarely observed for clinical evidence. Hepatitis B virus-related HCC is often accompanied by cirrhosis and portal hypertension; therefore, CD4+ tend to be relatively low in number. TACE is the standard treatment for Barcelona Clinic Liver Cancer (BCLC)-B HCC, which may further reduce the number of CD4 + .

Methods

This retrospective cohort study further reduced CD4+ by including patients with human immunodeficiency virus (HIV) to observe the relationship between CD4+ and Chronic hepatitis B virus (CHB) induced HCC. A total of 170 BCLC-B HCC patients (42 HIV+) were included. Univariate and multivariate analyses, and artificial neural networks (ANNs) were used to evaluate the independent risk factors for the two-year survival.

Results

The statistical analysis of the two-year survival rate showed that the main factors influencing survival were liver function and immune indices, including CD4+, platelet, alanine aminotransferase, aspartate aminotransferase, aspartate aminotransferase-to-platelet ratio index, and fibrosis-4 (FIB-4) (P < 0.05). Compared with that in other indices, in logistic and ANN multivariate analysis, CD4 + -to-FIB-4 ratio (CD4+/FIB-4) had the highest importance with 0.716 C-statistic and 145.93 cut-off value. In terms of overall survival rate, HIV infection was not a risk factor (P = 0.589); however, CD4+/FIB-4 ≤ 145.93 significantly affected patient prognosis (P = 0.002).

Conclusion

HIV infection does not affect the prognosis of BCLC-B HCC, but CD4+ have a significant predictive value. CD4+ played a vital role in HCC and this deserves the attention from physicians. Further, the CD4+/FIB-4 is a clinically valuable effective prognostic indicator for these patients.

Polyfunctional KLRG-1+CD57+ Senescent CD4+ T Cells Infiltrate Tumors and Are Expanded in Peripheral Blood From Breast Cancer Patients

Senescent T cells have been described during aging, chronic infections, and cancer; however, a comprehensive study of the phenotype, function, and transcriptional program of this T cell population in breast cancer (BC) patients is missing. Compared to healthy donors (HDs), BC patients exhibit an accumulation of KLRG-1⁺CD57⁺ CD4⁺ and CD8⁺ T cells in peripheral blood. These T cells infiltrate tumors and tumor-draining lymph nodes. KLRG-1⁺CD57⁺ CD4⁺ and CD8⁺ T cells from BC patients and HDs exhibit features of senescence, and despite their inhibitory receptor expression, they produce more effector cytokines and exhibit higher expression of Perforin, Granzyme B, and CD107a than non-senescent subsets. When compared to blood counterparts, tumor-infiltrating senescent CD4⁺ T cells show similar surface phenotype but reduced cytokine production. Transcriptional profiling of senescent CD4⁺ T cells from the peripheral blood of BC patients reveals enrichment in genes associated with NK or CD8⁺-mediated cytotoxicity, TCR-mediated stimulation, and cell exhaustion compared to non-senescent T cells. Comparison of the transcriptional profile of senescent CD4⁺ T cells from peripheral blood of BC patients with those of HDs highlighted marked similarities but also relevant differences. Senescent CD4⁺ T cells from BC patients show enrichment in T-cell signaling, processes involved in DNA replication, p53 pathways, oncogene-induced senescence, among others compared to their counterparts in HDs. High gene expression of CD4, KLRG-1, and B3GAT1 (CD57), which correlates with increased overall survival for BC patients, underscores the usefulness of the evaluation of the frequency of senescent CD4⁺ T cells as a biomarker in the follow-up of patients.

Splicing Patterns in SF3B1-Mutated Uveal Melanoma Generate Shared Immunogenic Tumor-Specific Neoepitopes

Disruption of splicing patterns due to mutations of genes coding splicing factors in tumors represents a potential source of tumor neoantigens, which would be both public (shared between patients) and tumor-specific (not expressed in normal tissues). In this study, we show that mutations of the splicing factor SF3B1 in uveal melanoma generate such immunogenic neoantigens. Memory CD8⁺ T cells specific for these neoantigens are preferentially found in 20% of patients with uveal melanoma bearing SF3B1-mutated tumors. Single-cell analyses of neoepitope-specific T cells from the blood identified large clonal T-cell expansions, with distinct effector transcription patterns. Some of these expanded T-cell receptors are also present in the corresponding tumors. CD8⁺ T-cell clones specific for the neoepitopes specifically recognize and kill SF3B1-mutated tumor cells, supporting the use of this new family of neoantigens as therapeutic targets. SIGNIFICANCE: Mutations of the splicing factor SF3B1 in uveal melanoma generate shared neoantigens that are uniquely expressed by tumor cells, leading to recognition and killing by specific CD8 T cells. Mutations in splicing factors can be sources of new therapeutic strategies applicable to diverse tumors.This article is highlighted in the In This Issue feature, p. 1861.

FAT3 Mutation Is Associated With Tumor Mutation Burden and Poor Prognosis in Esophageal Cancer

Objective

To explore the mutated genes in esophageal cancer (ESCA), and evaluate its relationship with tumor mutation burden (TMB) and prognosis of ESCA, and analyze the advantages of FAT3 as a potential prognostic marker in ESCA.

Methods

The somatic mutation landscape was analyzed according to ESCA samples from the TCGA and ICGC database. The differences of TMB between mutant type and wild type of frequently mutated genes were compared by Mann-Whitney U test. The association of gene mutations with prognosis was analyzed by Kaplan-Meier method. The relative abundance of 22 tumor-infiltrating lymphocyte subsets in ESCA was calculated by CIBERSORT algorithm.

Results

FAT3 was a high frequency mutation in both TCGA and ICGC samples from the somatic mutation landscape. Then, the mutation type of FAT3 had significantly higher TMB in patients with ESCA compared the wild type (P<0.05). Meanwhile, the prognosis of FAT3 mutation type was significantly worse in patients with ESCA(P<0.05), and the FAT3 mutation status might be an independent factor for prognosis of patients with ESCA (HR: 1.262-5.922, P=0.011). The GSEA analysis revealed the potential mechanism of FAT3 mutation on the occurrence and development of ESCA. Finally, naive B cells were significantly enriched in FAT3 mutation samples of the ESCA microenvironment (P<0.05).

Conclusions

FAT3 mutation is related to TMB and poor prognosis in ESCA. FAT3 mutation may be a prognostic marker of ESCA, and reveal the potential mechanism of FAT3 mutation on ESCA.

Neoadjuvant immune checkpoint inhibitors in cancer, current state of the art

Immunotherapy has been a revolution in cancer management in the metastatic setting. This has led to a prompt evaluation of such therapies in earlier stages. This article discusses the still limited amount of data finding the rationale to assess such therapy in this setting and reviews preclinical and clinical data available. Overall, neoadjuvant immunotherapy is a promising approach for the treatment of cancers and the rationale supporting its use is strong. Neoadjuvant immunotherapy resulted, in the majority of clinical trials, in improved pathologic complete response rates with a favorable toxicity profile and no delay in surgery. Various regimens were effective: inhibitory immune check-point blockers (IICPB) alone, combination of PD-1 and CTLA-4 inhibitors, combination of chemotherapy (CT) and IICPB, phased CT and IICPB (either IICPB before CT or IICPB after CT). Yet the question whether neoadjuvant immunotherapy will benefit to patients in terms of disease-free and, ultimately, overall survival remains unknown.

Circulating immune cell phenotype dynamics reflect the strength of tumor-immune cell interactions in patients during immunotherapy

The extent to which immune cell phenotypes in the peripheral blood reflect within-tumor immune activity prior to and early in cancer therapy is unclear. To address this question, we studied the population dynamics of tumor and immune cells, and immune phenotypic changes, using clinical tumor and immune cell measurements and single-cell genomic analyses. These samples were serially obtained from a cohort of advanced gastrointestinal cancer patients enrolled in a trial with chemotherapy and immunotherapy. Using an ecological population model, fitted to clinical tumor burden and immune cell abundance data from each patient, we find evidence of a strong tumor-circulating immune cell interaction in responder patients but not in those patients that progress on treatment. Upon initiation of therapy, immune cell abundance increased rapidly in responsive patients, and once the peak level is reached tumor burden decreases, similar to models of predator-prey interactions; these dynamic patterns were absent in nonresponder patients. To interrogate phenotype dynamics of circulating immune cells, we performed single-cell RNA sequencing at serial time points during treatment. These data show that peripheral immune cell phenotypes were linked to the increased strength of patients' tumor-immune cell interaction, including increased cytotoxic differentiation and strong activation of interferon signaling in peripheral T cells in responder patients. Joint modeling of clinical and genomic data highlights the interactions between tumor and immune cell populations and reveals how variation in patient responsiveness can be explained by differences in peripheral immune cell signaling and differentiation soon after the initiation of immunotherapy.

Breast cancer immunology and immunotherapy: targeting the programmed cell death protein-1/programmed cell death protein ligand-1

Historically, breast cancer has been regarded as an immunogenic "cold" tumor. However, the discovery of immune checkpoint inhibitors has made immunotherapy becoming an emerging new treatment modality for breast cancer. This review discusses the immune system, immune features of breast cancer, and the programmed cell death protein-1/programmed cell death protein ligand-1 (PD-1/PD-L1) inhibitors used in the treatment of breast cancer. High T lymphocyte infiltration and mutation burden were observed in triple-negative breast cancer and human epidermal growth factor receptor 2 positive breast cancer. Increasing breast cancer immunogenicity and modulating the tumor microenvironment has been reported to improve the therapeutic efficacy of immunotherapy. Recent clinical trials involving PD-1/PD-L1 inhibitors monotherapy in breast cancer has revealed little efficacy, which highlights the need to develop combinations of PD-1/PD-L1 inhibitors with chemotherapy, molecularly targeted therapies, and other immunotherapies to maximize the clinical efficacy. Collectively, the immunotherapy might be a promising therapeutic strategy for breast cancer and several clinical trials are still on-going.

Targeting Interleukin(IL)-30/IL-27p28 signaling in cancer stem-like cells and host environment synergistically inhibits prostate cancer growth and improves survival

Background

Interleukin(IL)-30/IL-27p28 production by Prostate Cancer (PC) Stem-Like Cells (SLCs) has proven, in murine models, to be critical to tumor onset and progression. In PC patients, IL-30 expression by leukocytes infiltrating PC and draining lymph nodes correlates with advanced disease grade and stage. Here, we set out to dissect the role of host immune cell-derived IL-30 in PC growth and patient outcome.

Methods

PC-SLCs were implanted in wild type (WT) and IL-30 conditional knockout (IL-30KO) mice. Histopathological and cytofluorimetric analyses of murine tumors and lymphoid tissues prompted analyses of patients’ PC samples and follow-ups.

Results

Implantation of PC-SLCs in IL-30KO mice, gave rise to slow growing tumors characterized by apoptotic events associated with CD4⁺T lymphocyte infiltrates and lack of CD4⁺Foxp3⁺ T regulatory cells (Tregs). IL-30 knockdown in PC-SLCs reduced cancer cell proliferation, vascularization and intra-tumoral Indoleamine 2,3-Dioxygenase (IDO)⁺CD11b⁺Gr-1⁺ myeloid-derived cells (MDCs) and led to a significant delay in tumor growth and increase in survival. IL-30-silenced tumors developed in IL-30KO mice, IL-30^−/−tumors, lacked vascular supply and displayed frequent apoptotic cancer cells entrapped by perforin⁺TRAIL⁺CD3⁺Tlymphocytes, most of which had a CD4⁺T phenotype, whereas IL-10⁺TGFβ⁺Foxp3⁺Tregs were lacking. IL-30 silencing in PC-SLCs prevented lung metastasis in 73% of tumor-bearing WT mice and up to 80% in tumor-bearing IL-30KO mice.

In patients with high-grade and locally advanced PC, those with IL-30^−/−tumors, showed distinct intra-tumoral cytotoxic granule-associated RNA binding protein (TIA-1)⁺CD4⁺Tlymphocyte infiltrate, rare Foxp3⁺Tregs and a lower biochemical recurrence rate compared to patients with IL-30^+/+tumors in which IL-30 is expressed in both tumor cells and infiltrating leukocytes.

Conclusion

The lack of host leukocyte-derived IL-30 inhibits Tregs expansion, promotes intra-tumoral infiltration of CD4⁺T lymphocytes and cancer cell apoptosis. Concomitant lack of MDC influx, obtained by IL-30 silencing in PC-SLCs, boosts cytotoxic T lymphocyte activation and cancer cell apoptosis resulting in a synergistic tumor suppression with the prospective benefit of better survival for patients with advanced disease.

Electronic supplementary material

The online version of this article (10.1186/s40425-019-0668-z) contains supplementary material, which is available to authorized users.

Targeted and immuno-biology driven treatment strategies for triple-negative breast cancer: current knowledge and future perspectives

Introduction: Accounting for about 15% of breast cancer patients, triple-negative breast cancer (TNBC) is responsible for 25% of disease related deaths, more frequent distant spread and visceral metastasis. However, improving survival in TNBC failed and primary resistance, immunological ignorance and tumor heterogeneity limit clinical activity of novel therapies. In view of recent molecular, genetic and immunologic insights, this review aims to describe the current status of immunological and targeted treatments from a hypothesis driven perspective. Areas covered: Recent preclinical studies and ongoing clinical trials for immune directed and targeted treatments of TNBC are summarized, including immune-checkpoint blockade, resistance mechanisms, inhibition of poly (ADP-ribose) polymerase (PARP), combinatorial strategies as well as preclinical, hypothesis generating studies. Expert commentary: Sustained responses have been observed with immune-checkpoint blockade and PARP inhibitors demonstrated remarkable efficacy in germline BRCA mutated TNBC. In order to generate clinical success of many other, to date ineffective, targeted and immune therapies, the integration of multidimensional, large amounts of data, will be essential and likely accelerate treatment progress of TNBC.

Induction of anergic or regulatory tumor-specific CD4+ T cells in the tumor-draining lymph node

CD4⁺ T cell antitumor responses have mostly been studied in transplanted tumors expressing secreted model antigens (Ags), while most mutated proteins in human cancers are not secreted. The fate of Ag-specific CD4⁺ T cells recognizing a cytoplasmic Ag in mice bearing autochthonous tumors is still unclear. Here we show, using a genetically engineered lung adenocarcinoma mouse model, that naive tumor-specific CD4⁺ T cells are activated and proliferate in the tumor-draining lymph node (TdLN) but do not differentiate into effectors or accumulate in tumors. Instead, these CD4⁺ T cells are driven toward anergy or peripherally-induced Treg (pTreg) differentiation, from the early stage of tumor development. This bias toward immune suppression is restricted to the TdLN, and is maintained by Tregs enriched in the tumor Ag-specific cell population. Thus, tumors may enforce a dominant inhibition of the anti-tumor CD4 response in the TdLN by recapitulating peripheral self-tolerance mechanisms.

Tumor neoantigens can be drained to the lymph nodes, but the nature and the significance of the induced immune responses are still unclear. Here the authors use a mouse genetic tumor model to show that tumor-specific CD4 T cells can become anergic or suppressive in the draining lymph node to modulate tumor immunity.

Blood monocytes sample MelanA/MART1 antigen for long-lasting cross-presentation to CD8+ T cells after differentiation into dendritic cells

Human blood monocytes are very potent to take up antigens. Like macrophages in tissue, they efficiently degrade exogenous protein and are less efficient than dendritic cells (DCs) at cross-presenting antigens to CD8⁺ T cells. Although it is generally accepted that DCs take up tissue antigens and then migrate to lymph nodes to prime T cells, the mechanisms of presentation of antigens taken up by monocytes are poorly documented so far. In the present work, we show that monocytes loaded in vitro with MelanA long peptides retain the capacity to stimulate antigen-specific CD8⁺ T cell clones after 5 days of differentiation into monocytes-derived dendritic cells (MoDCs). Tagged-long peptides can be visualized in electron-dense endocytic compartments distinct from lysosomes, suggesting that antigens can be protected from degradation for extended periods of time. To address the pathophysiological relevance of these findings, we screened blood monocytes from 18 metastatic melanoma patients and found that CD14⁺ monocytes from two patients effectively activate a MelanA-specific CD8 T cell clone after in vitro differentiation into MoDCs. This in vivo sampling of tumor antigen by circulating monocytes might alter the tumor-specific immune response and should be taken into account for cancer immunotherapy.

Trastuzumab emtansine (T-DM1) renders HER2+ breast cancer highly susceptible to CTLA-4/PD-1 blockade

Targeted drug delivery with antibody-drug conjugates such as the HER2-directed ado-trastuzumab emtansine (T-DM1) has emerged as a powerful strategy for cancer therapy. We show that T-DM1 is particularly effective in eliciting antitumor immunity in patients with early breast cancer (WSG-ADAPT trial) and in a HER2-expressing orthotopic tumor model. In the latter, despite primary resistance to immunotherapy, combined treatment with T-DM1 and anti-CTLA-4/PD-1 (cytotoxic T lymphocyte-associated protein-4/programmed cell death protein-1) was curative because it triggered innate and adaptive immunity. Tumor rejection was accompanied by massive T cell infiltration, TH1 (T helper 1) cell polarization, and, notably, a substantial increase in regulatory T cells. Depletion of regulatory T cells resulted in inflammation and tissue damage, implying their essential role in protecting the host during therapy. This study provides insights into the mechanisms of T-DM1's therapeutic activity and a rationale for potential therapeutic combination strategies with immunotherapy.

Prognostic Effect of Tumor Lymphocytic Infiltration in Resectable Non-Small-Cell Lung Cancer

PURPOSE

Tumor lymphocytic infiltration (TLI) has differing prognostic value among various cancers. The objective of this study was to assess the effect of TLI in lung cancer.

PATIENTS AND METHODS

A discovery set (one trial, n = 824) and a validation set (three trials, n = 984) that evaluated the benefit of platinum-based adjuvant chemotherapy in non-small-cell lung cancer were used as part of the LACE-Bio (Lung Adjuvant Cisplatin Evaluation Biomarker) study. TLI was defined as intense versus nonintense. The main end point was overall survival (OS); secondary end points were disease-free survival (DFS) and specific DFS (SDFS). Hazard ratios (HRs) and 95% CIs associated with TLI were estimated through a multivariable Cox model in both sets. TLI-histology and TLI-treatment interactions were explored in the combined set.

RESULTS

Discovery and validation sets with complete data included 783 (409 deaths) and 763 (344 deaths) patients, respectively. Median follow-up was 4.8 and 6 years, respectively. TLI was intense in 11% of patients in the discovery set compared with 6% in the validation set (P < .001). The prognostic value of TLI in the discovery set (OS: HR, 0.56; 95% CI, 0.38 to 0.81; P = .002; DFS: HR, 0.59; 95% CI, 0.42 to 0.83; P = .002; SDFS: HR, 0.56; 95% CI, 0.38 to 0.82; P = .003) was confirmed in the validation set (OS: HR, 0.45; 95% CI, 0.23 to 0.85; P = .01; DFS: HR, 0.44; 95% CI, 0.24 to 0.78; P = .005; SDFS: HR, 0.42; 95% CI, 0.22 to 0.80; P = .008) with no heterogeneity across trials (P ≥ .38 for all end points). No significant predictive effect was observed for TLI (P ≥ .78 for all end points).

CONCLUSION

Intense lymphocytic infiltration, found in a minority of tumors, was validated as a favorable prognostic marker for survival in resected non-small-cell lung cancer.

Natural and therapy-induced immunosurveillance in breast cancer

The immunosurveillance theory postulates that tumors evolve and progress in an uncontrolled fashion only when anticancer immune responses fail. Natural immunosurveillance clearly influences human breast cancer (BC) progression because the prognosis of BC patients is dictated by the density, composition and activity of the tumor immune infiltrate at diagnosis. Moreover, chemotherapeutic and radiotherapeutic regimens commonly employed for the treatment of BC affect the tumor immune infiltrate, and accumulating data suggest that the clinical efficacy of these treatments is largely determined by T cell-dependent tumor-specific immune responses. In addition, the mechanism of action of targeted anticancer therapeutics, such as the erb-b2 receptor tyrosine kinase 2 (ERBB2)-targeting agent trastuzumab, involves the innate and adaptive arms of the immune system. In this Review, we discuss these findings as well as preliminary evidence indicating that immunotherapy constitutes a promising option for the treatment of BC. Moreover, we point out that the successful implementation of immunotherapy to BC management requires the optimization of current immunotherapeutic regimens and the identification of immunological biomarkers that enable improved risk stratification and the design of personalized, dynamic treatment plans.

Upcoming translational challenges for uveal melanoma

The past few years have witnessed major advances in the understanding of the molecular landscape of uveal melanoma (UM). The discovery of a mutational background that is completely different from the one of skin melanoma has granted to UM a stand-alone status. The absence of effective therapy for metastatic disease offers now a chessboard for targeted therapy but at the same time urges preclinical science to develop accordingly, to guide the use of economical resources to the best profit of patients. This review describes the current knowledge on the biology of this disease and discusses the challenges that must be undertaken to translate this knowledge into real benefit for patients.

Tumor-infiltrating CD45RO(+) memory cells are associated with a favorable prognosis breast cancer

BACKGROUND

CD45RO is a marker for memory lymphocytes. Whether CD45RO(+) tumor-infiltrating lymphocytes (TILs) prevent breast cancer recurrence is unclear.

METHODS

In the present study, we evaluated CD45RO expression in TILs as a predictor of prognosis in 98 patients with breast cancer who underwent radical surgery without neoadjuvant chemotherapy. Patients were classified as CD45RO(+)/TILs(High) or CD45RO(+)/TILs(Low) based on median immunohistochemistry levels.

RESULTS

CD45RO(+)/TILs(High) were associated with smaller tumor size. The CD45RO(+)/TILs(High) group also had significantly fewer metastatic lymph nodes (P = 0.0082) and fewer peritumoral lymphatic invasions (P = 0.0284). The CD45RO(+)/TILs(High) group enjoyed longer recurrence-free survival (P = 0.0453) but not cancer-specific survival (P = 0.0640) in univariate analysis.

CONCLUSIONS

These results suggested that CD45RO(+) effector cells may both help eradicate local tumors and prevent metastases to the lymphatic systems in breast cancer patients. High ratio of CD45RO expressing TILs was associated with recurrence-free survival improvement and a trend toward cancer-specific survival improvement in breast cancer patients.

Modeling the specific CD4+ T cell response against a tumor neoantigen

The antitumor activity of CD4(+) T cells is increasingly acknowledged in both humans and mice. The involved mechanisms have been mostly studied using transplanted tumor mouse systems. In these models, many tumor cells die at the time of implantation leading to the release of Ag in an inflammatory context contrasting with the slow and nondestructive growth of early-stage human tumors. In this study, we show that the presentation of a MHC class II-restricted model Ag (male, DBY) released by dying tumor cells may last more than 4 wk. The duration of Ag presentation varies according to the way the cells are killed before implantation. To avoid this artifactual early priming of the host precluding the study of the interactions between the immune system and tumors at the steady state, we generated a cell line expressing the DBY Ag in an inducible manner. Ag expression can be efficiently induced in vivo several days after tumor implantation. We show that the Ag reaches the lymph node and activates naive CD4(+) T cells to proliferate and recirculate. We did not observe de novo induction of tumor-specific regulatory T cells. However, we observed Th1/Th17 effector cells in the tumor draining lymph node and tumors. Thus, when a neoantigen appears in established tumors, the immune system is not ignorant and naive CD4(+) T cells are not tolerized. This opens up the possibility of therapeutic vaccines improving the immune response toward tumor-specific neoantigens.

Strengthened tumor antigen immune recognition by inclusion of a recombinant Eimeria antigen in therapeutic cancer vaccination

The need for novel, effective adjuvants that are capable of eliciting stronger cellular and humoral adaptive immune responses to antigenic targets is well understood in the vaccine development field. Unfortunately, many adjuvants investigated thus far are either too toxic for human application or too weak to induce a substantial response against difficult antigens, such as tumor-associated antigens (TAAs). In spite of this trend, clinical investigations of recombinant Eimeria antigen (rEA) have revealed this protein to be a non-toxic immunogenic agent with the ability to trigger a Th1-predominant response in both murine and human subjects. Our past studies have shown that the injection of a rEA-encoding adenovirus (rAd5-rEA) alongside an HIV antigen-encoding adenovirus greatly improves the adaptive immune response against this pathogen-derived transgene. In this report, we investigated whether rAd5-rEA could promote and/or alter cytotoxic memory responses toward carcinoembryonic antigen (CEA), a colorectal cancer-related TAA. We found that the addition of rAd5-rEA to an Ad-based CEA vaccine induced a dose-dependent increase in several anti-CEA T and B cell responses. Moreover, inclusion of rAd5-rEA increased the number of CEA-derived antigenic epitopes that elicited significant cell-mediated and IgG-mediated recognition. These enhanced anti-CEA immune responses also translated into superior CEA-targeted cell killing, as evaluated by an in vivo cytotoxic T lymphocyte assay. Overall, these results suggest that co-administration of rAd5-rEA with a tumor antigen vaccine can substantially boost and broaden the TAA-specific adaptive memory response, thereby validating the potential of rAd5-rEA to be a beneficial adjuvant during therapeutic cancer vaccination.

Comparative immune phenotypic analysis of cutaneous Squamous Cell Carcinoma and Intraepidermal Carcinoma in immune-competent individuals: proportional representation of CD8+ T-cells but not FoxP3+ Regulatory T-cells is associated with disease stage

Squamous Cell Carcinoma (SCC) is a type of non-melanoma skin cancer prevalent in immune-suppressed transplant recipients and older individuals with a history of chronic sun-exposure. SCC itself is believed to be a late-stage manifestation that can develop from premalignant lesions including Intraepidermal Carcinoma (IEC). Notably, while SCC regression is rare, IEC typically regresses in response to immune modifying topical treatments, however the underlying immunological reasons for these differential responses remain unclear. This study aimed to define whether IEC and SCC are associated with distinct immune profiles. We investigated the immune cell infiltrate of photo-damaged skin, IEC, and SCC tissue using 10-colour flow cytometry following fresh lesion digest. We found that IEC lesions contain higher percentages of CD3⁺ T-cells than photo-damaged skin, however, the abundance of CD3⁻CD56⁺ Natural Killer (NK) cells, CD11c⁺HLA-DR⁺ conventional Dendritic Cells (cDC), BDCA-2⁺HLA-DR⁺ plasmacytoid DC (pDC), FoxP3⁺ Regulatory T-cells (T-reg), Vα24⁺Vβ11⁺ invariant NKT-cells, and γδ Tcells did not alter with disease stage. Within the total T-cell population, high percentages of CD4⁺ T-cells were associated with SCC, yet CD8⁺ T-cells were less abundant in SCC compared with IEC. Our study demonstrates that while IEC lesions contain a higher proportion of T-cells than SCC lesions in general, SCC lesions specifically display a lower abundance of CD8⁺ T-cells than IEC. We propose that differences in CD8⁺ T-cell abundance contribute critically to the different capacity of SCC and IEC to regress in response to immune modifying topical treatments. Our study also suggests that a high ratio of CD4⁺ T-cells to CD8⁺ T-cells may be a immunological diagnostic indicator of late-stage SCC development in immune-competent patients.

Early treatment with anti-VLA-4 mAb can prevent the infiltration and/or development of pathogenic CD11b+CD4+ T cells in the CNS during progressive EAE

Natalizumab is a humanized monoclonal antibody against the leukocyte adhesion molecule very late antigen (VLA)-4, and is currently an approved therapy for patients with relapsing-remitting multiple sclerosis (RRMS). However, it is unknown whether natalizumab is beneficial for progressive forms of MS. Therefore, we assessed the effects of anti-VLA-4 monoclonal antibody (mAb) therapy in a progressive experimental autoimmune encephalomyelitis (EAE) mouse model. Notably, we found that early therapy could significantly reduce the severity of progressive EAE, while treatment initiated at an advanced stage was less efficient. Furthermore, we observed the accumulation of a novel subset of GM-CSF-producing CD11b+CD4+ T cells in the CNS throughout disease progression. Importantly, early therapeutic anti-VLA-4 mAb treatment suppressed the accumulation of these GM-CSF-producing CD11b+CD4+ T cells in the CNS along with activated microglia/macrophages populations, and also conferred a protective effect against inflammation-mediated neurodegeneration, including demyelination and axonal loss. Collectively, our data suggest that early treatment with anti-VLA-4 mAb can provide neuroprotection against progressive CNS autoimmune disease by preventing the accumulation of pathogenic GM-CSF-producing CD11b+CD4+ T cells in the CNS.