Increased B Regulatory Phenotype in Non-Metastatic Lymph Nodes of Node-Positive Breast Cancer Patients

Bioinformatic analysis and experimental validation of six cuproptosis-associated genes as a prognostic signature of breast cancer

Background

Breast carcinoma (BRCA) is a life-threatening malignancy in women and shows a poor prognosis. Cuproptosis is a novel mode of cell death but its relationship with BRCA is unclear. This study attempted to develop a cuproptosis-relevant prognostic gene signature for BRCA.

Methods

Cuproptosis-relevant subtypes of BRCA were obtained by consensus clustering. Differential expression analysis was implemented using the 'limma' package. Univariate Cox and multivariate Cox analyses were performed to determine a cuproptosis-relevant prognostic gene signature. The signature was constructed and validated in distinct datasets. Gene set variation analysis (GSVA) and gene set enrichment analysis (GSEA) were also conducted using the prognostic signature to uncover the underlying molecular mechanisms. ESTIMATE and CIBERSORT algorithms were applied to probe the linkage between the gene signature and tumor microenvironment (TME). Immunotherapy responsiveness was assessed using the Tumor Immune Dysfunction and Exclusion (TIDE) web tool. Real-time quantitative PCR (RT-qPCR) was performed to detect the expressions of cuproptosis-relevant prognostic genes in breast cancer cell lines.

Results

Thirty-eight cuproptosis-associated differentially expressed genes (DEGs) in BRCA were mined by consensus clustering and differential expression analysis. Based on univariate Cox and multivariate Cox analyses, six cuproptosis-relevant prognostic genes, namely SAA1, KRT17, VAV3, IGHG1, TFF1, and CLEC3A, were mined to establish a corresponding signature. The signature was validated using external validation sets. GSVA and GSEA showed that multiple cell cycle-linked and immune-related pathways along with biological processes were associated with the signature. The results ESTIMATE and CIBERSORT analyses revealed significantly different TMEs between the two Cusig score subgroups. Finally, RT-qPCR analysis of cell lines further confirmed the expressional trends of SAA1, KRT17, IGHG1, and CLEC3A.

Conclusion

Taken together, we constructed a signature for projecting the overall survival of BRCA patients and our findings authenticated the cuproptosis-relevant prognostic genes, which are expected to provide a basis for developing prognostic molecular biomarkers and an in-depth understanding of the relationship between cuproptosis and BRCA.

The Evolving Landscape of B Cells in Cancer Metastasis

Metastasis is the leading cause of cancer mortality. Functional and clinical studies have documented diverse B-cell and antibody responses in cancer metastasis. The presence of B cells in tumor microenvironments and metastatic sites has been associated with diverse effects that can promote or inhibit metastasis. Specifically, B cells can contribute to the spread of cancer cells by enhancing tumor cell motility, invasion, angiogenesis, lymphangiogenesis, and extracellular matrix remodeling. Moreover, they can promote metastatic colonization by triggering pathogenic immunoglobulin responses and recruiting immune suppressive cells. Contrastingly, B cells can also exhibit antimetastatic effects. For example, they aid in enhanced antigen presentation, which helps activate immune responses against cancer cells. In addition, B cells play a crucial role in preventing the dissemination of metastatic cells from the primary tumor and secrete antibodies that can aid in tumor recognition. Here, we review the complex roles of B cells in metastasis, delineating the heterogeneity of B-cell activity and subtypes by metastatic site, antibody class, antigen (if known), and molecular phenotype. These important attributes of B cells emphasize the need for a deeper understanding and characterization of B-cell phenotypes to define their effects in metastasis.

Dual Functions of T Lymphocytes in Breast Carcinoma: From Immune Protection to Orchestrating Tumor Progression and Metastasis

Breast cancer (BC) is the most common cancer type in women and the second leading cause of death. Despite recent advances, the mortality rate of BC is still high, highlighting a need to develop new treatment strategies including the modulation of the immune system and immunotherapies. In this regard, understanding the complex function of the involved immune cells and their crosstalk with tumor cells is of great importance. T-cells are recognized as the most important cells in the tumor microenvironment and are divided into several subtypes including helper, cytotoxic, and regulatory T-cells according to their transcription factors, markers, and functions. This article attempts to provide a comprehensive review of the role of T-cell subsets in the prognosis and treatment of patients with BC, and crosstalk between tumor cells and T-cells. The literature overwhelmingly contains controversial findings mainly due to the plasticity of T-cell subsets within the inflammatory conditions and the use of different panels for their phenotyping. However, investigating the role of T-cells in BC immunity depends on a variety of factors including tumor types or subtypes, the stage of the disease, the localization of the cells in the tumor tissue and the presence of different cells or cytokines.

Expression of Interleukin-21 and Interleukin-21 receptor in lymphocytes derived from tumor-draining lymph nodes of breast cancer

BACKGROUND

Interleukin-21 (IL-21) is produced by various cell types inducing positive and negative effects in immunity against tumors.

OBJECTIVE

To investigate the expression of IL-21 by CD4+T and IL-21 receptor (IL-21R) by B lymphocytes isolated from breast-tumor draining lymph nodes (TDLNs).

METHODS

Fresh lymph node samples were obtained from 45 patients with breast cancer. To assess IL-21 expression, mononuclear cells were briefly stimulated whereas IL-21R expression was assessed in unstimulated B cells. Cells were stained with antibodies for CD4, IL-21, CD19 and IL-21R and acquired by flow cytometry.

RESULTS

The frequency of IL-21+CD4+T cells did not show significant association with disease parameters. However, the geometric mean fluorescence intensity (gMFI) of IL-21 in CD4+T cells was significantly lower in patients with grade III tumor than grade I + II (P = 0.042). In non-involved LNs, the intensity of IL-21 was significantly higher in patients with stage II compared with stage III (P = 0.038) and correlated negatively with the number of involved LNs. The frequency of IL-21R+CD19+B cells was significantly higher in grade III than grade I + II (P = 0.037).

CONCLUSION

The higher intensity of IL-21 in CD4+T cells showed association with good prognosticators in breast cancer and warrants further investigation of the role played by IL-21 in immunity against breast cancer.

Immune Crosstalk Between Lymph Nodes and Breast Carcinomas, With a Focus on B Cells

Lymph nodes (LNs) are highly organized secondary lymphoid organs, and reflective of immune responses to infection, injuries, or the presence of cancer. Extensive molecular and morphological analyses of immune and stromal features in tumors and LNs of breast cancer patients have revealed novel patterns indicative of disease progression. Within LNs, there are dynamic structures called germinal centers (GCs), that act as the immunological hubs for B cell development and generation of affinity matured memory B and antibody-producing plasma cells. Acting as a bridge between systemic and local immunity, associations are observed between the frequency of GCs within cancer-free LNs, the levels of stromal tumor infiltrating lymphocytes, and cancer progression. Scattered throughout the tumor microenvironment (TME) or aggregated in clusters forming tertiary lymphoid structures (TLS), the occurrence of tumor infiltrating B cells (TIL-Bs) has been linked mostly to superior disease trajectories in solid cancers. Recent TIL-Bs profiling studies have revealed a plethora of different TIL-B populations, their functional roles, and whether they are derived from GC reactions in the LN, and/or locally from GC-like structures within the TME remains to be investigated. However, parallels between the immunogenic nature of LNs as a pre-metastatic niche, TIL-B populations within the TME, and the presence of TLS will help to decipher local and widespread TIL-Bs responses and their influence on cancer progression to the lymphatics. Therapies that enhance TIL-Bs responses in the LN GC and/or in GC-like structures in the TME are thus emerging management strategies for breast and other cancer patients.

Prognostic significance of CD4-positive regulatory T cells in tumor draining lymph nodes from patients with bladder cancer

Introduction and methods

To clarify the role of CD4⁺ regulatory T cells in bladder cancer, we investigated the frequency of these cells in tumor draining lymph nodes of 50 patients with bladder cancer who underwent radical cystectomy using flow cytometry method. We also assessed their association with prognosis and survival.

Results

On average, 30.13 ± 2.17% of lymphocytes in draining lymph nodes from patients with bladder cancer were positive for both CD4 and FOXP3 molecules. Analyses also showed that 9.92 ± 0.8% of CD4⁺ lymphocytes had a regulatory phenotype (CD4⁺CD25⁺FOXP3⁺CD127^low/neg). The frequency of total CD4⁺FOXP3⁺ lymphocytes as well as regulatory T cells was significantly greater in patients with at least one tumor-involved lymph node compared to those with tumor-free nodes (P = 0.026 and P = 0.036, respectively). Mean FOXP3 expression in CD4⁺ lymphocytes was greater in patients with stage IV compared with those in stage III (P = 0.046). No other significant associations were found between the frequency of regulatory T cells and other clinicopathological characteristics or patient survival.

Conclusions

The increased frequency of regulatory T cells in patients with involved lymph nodes suggests that these cells may negatively regulate antitumor immune responses in draining lymph nodes. Our findings may have implications for immunotherapy-based treatments for bladder cancer.

Significance of TIM-3 expression by CD4+ and CD8+ T lymphocytes in tumor-draining lymph nodes from patients with breast cancer

T cell immunoglobulin and mucin domain-containing protein 3 (TIM-3), which is expressed by immune and nonimmune cells, has been shown to play immunoregulatory roles in the tumor microenvironment. In this study we assessed the expression of TIM-3 by T cells from tumor draining lymph nodes (TDLNs) of patients with breast cancer and its association with disease progression. Lymphocytes were isolated from 41 TDLNs, and flow cytometry was used to determine the expression of TIM-3 on CD4⁺ and CD8⁺ T cells, along with the simultaneous expression of CD25, Foxp3 and TIM-3 in CD4⁺ T cells. The results showed that the frequency of TIM-3⁺CD8⁺ T cells was associated with higher tumor grade, and the geometric mean fluorescence intensity (gMFI) of TIM-3 in CD4⁺ and CD8⁺ T cells was significantly higher in patients with more than 9 involved lymph nodes than those with fewer involved nodes. The gMFI of TIM3 in CD4⁺ T cells also showed a direct correlation with the number of metastatic lymph nodes. Phenotypic characterization of TIM-3⁺CD4⁺ T cells showed that the majority of CD4⁺TIM3⁺ lymphocytes were Foxp3 ^̶ CD25 ^̶, and the majority of Foxp3⁺CD25⁺ regulatory T cells were TIM-3^-. Our findings showed that TIM-3 was expressed by CD4⁺, CD8⁺ and regulatory T cells in breast TDLNs, and that expression on CD4⁺ and CD8⁺ T cells was mostly associated with poor prognosticators such as a higher number of involved lymph nodes or higher tumor grade. More studies are required to confirm TIM-3 as a prognostic marker and a target for immunotherapy in breast cancer.

The balance of regulatory and stimulatory B cell subsets in breast cancer draining lymph nodes correlates with tumor prognostic factors

AIMS

B cells can promote or inhibit immune responses against breast cancer. We investigated changes in the frequency of B cells with stimulatory or regulatory capacity in breast tumor draining lymph nodes during cancer progression.

MAIN METHODS

We isolated mononuclear cells from fresh axillary lymph nodes (LNs) of 44 patients with breast cancer and stained lymphocytes with antibodies against CD19, CD80, CD86, CD39 and CD73. To assess programmed death-1 (PD-1) and PD-ligand 1 (PD-L1) expression, lymphocytes were briefly stimulated, stained for CD19, PD-1 and PD-L1, and examined with flow cytometry.

KEY FINDINGS

The frequency of CD80⁺ B cells was higher in nonmetastatic lymph nodes, while the percentage of CD86⁺ B cells showed a positive relationship with higher tumor grade and higher numbers of involved LNs. A small proportion of unstimulated B cells expressed PD-1 or PD-L1 but these molecules were rapidly upregulated on B cells following activation. The frequency of stimulated PD-L1⁺ B cells showed an inverse association with estrogen and progesterone receptor expression and a nonsignificant positive association with tumor grade. In addition, the percentage of unstimulated PD-1⁺ B cells was higher in patients with higher-grade tumors. CD73 expression on B cells was associated with lower numbers of involved LNs, and the frequency of CD39⁺ B cells was higher in patients with larger tumors.

SIGNIFICANCE

CD86⁺, CD39⁺, PD-1⁺ and PD-L1⁺ B cells showed associations with poor prognostic factors, therefore their potential role in the suppression of the immune responses against breast cancer should be evaluated in greater detail.

CD8-positive memory T cells in tumor-draining lymph nodes of patients with breast cancer

Background

Human immunological memory is a hallmark of the adaptive immune system and plays an important role in the development of effective immune responses against tumors. In the present study, we aimed to determine the frequencies of CD8⁺ memory T cell subsets including T stem cell memory (TSCM) in tumor-draining lymph nodes of patients with breast cancer (BC).

Methods

Mononuclear cells were obtained from axillary lymph nodes of 52 untreated patients with BC and stained for CD8, CCR7, CD45RO, CD95 markers to detect different subtypes of memory cells in the CD8⁺ lymphocyte population. Data were acquired on four-color flow cytometer and analyzed with CellQuest Pro software.

Results

We observed that 47.65 ± 2.66% of CD8⁺ lymphocytes expressed the CD45RO, a marker for memory T cells. Statistical analysis showed that the total frequency of central memory T cells (TCM) and their subset with low CD45RO expression was significantly higher in tumor-involved nodes compared to tumor-free ones (P = 0.024 and P = 0.017, respectively). The level of CD95 expression (based on mean fluorescence intensity) on the surface of TCM, their CD45RO^hi and CD45RO^low subsets, and TSCM was higher in patients with stage II compared to those in stage I (P < 0.05). In addition, the percentage of naive CD8⁺ T cells was significantly lower in tumor-involved lymph nodes compared to tumor-free ones (P = 0.025).

Conclusions

Our data collectively indicate no significant differences in the frequencies of CD8⁺ lymphocytes or their memory subsets in tumor-draining lymph nodes of patients with BC. However, the frequency of CD45^low TCM was higher in tumor-involved nodes. Along with a decrease in the frequency of naive T cells, the higher frequency of CD45^low TCM suggests that despite the immune reaction to provide a pool of effective memory cells, it is blocked in early-stage of memory cells’ differentiation (CD45RO^low), probably by tumor-derived suppressive factors. Identifying the molecular and cellular mechanisms behind this suppression can provide invaluable tools for adoptive T cell therapies in cancer.

Cytokine profile of CD4+CD25-FoxP3+ T cells in tumor-draining lymph nodes from patients with breast cancer

BACKGROUND

A T cell subtype with the CD4+CD25-FoxP3+ phenotype was recently described. We aimed to investigate the frequency of these cells and their ability to produce cytokines in tumor-draining lymph nodes from patients with breast cancer (BC).

MATERIALS AND METHODS

Mononuclear cells from lymph nodes of 20 patients with BC were activated and stained for appropriate markers. The cells were assayed with four-color flow cytometry.

RESULTS

A very small fraction of CD4+CD25-FoxP3+ cells produced cytokines at levels that were significantly lower than in the regulatory (CD4+CD25+FoxP3+) and effector cell (CD4+CD25+FoxP3-) subpopulations. The expression of IFNγ and IL-2 in the CD4+CD25-FoxP3+ subset was significantly higher than in Treg cells, but lower than in the effector subset. Conversely, IL-22 expression in Treg cells was significantly higher than in the CD4+CD25-FoxP3+ subpopulation. The expression of IL-10 in the CD4+CD25-FoxP3+ subset was also significantly higher than in effector cells.

CONCLUSION

We suggest that CD4+CD25-FoxP3+ cells in patients with BC are exhausted cells with an intermediate phenotype between effector and regulatory cells.

Atypical Memory and Regulatory B Cell Subsets in Tumor Draining Lymph Nodes of Head and Neck Squamous Cell Carcinoma Correlate with Good Prognostic Factors

Research on the role of B cells in the development and modulation of antitumor immunity has increased in recent years; however, knowledge about B cell phenotype and function in tumor draining lymph nodes (TDLNs) is still incomplete. This study aimed to investigate changes in the phenotypic profile of B cells in TDLNs of head and neck squamous cell carcinoma (HNSCC) during disease progression. Mononuclear cells were isolated from TDLNs and stained with antibodies for CD19 and other B cell-related markers and analyzed by flow cytometry. CD19⁺ B cells comprised 38.6 ± 8.9% of lymphocytes in TDLNs of HNSCC. Comparison of metastatic and non-metastatic LNs disclosed no significant differences in the frequencies of B cell subsets including antigen-experienced, naïve, switched, unswitched, atypical memory, marginal zone-like B cells, and B cells with regulatory phenotypes. The percentage of atypical memory (CD27^-IgM^-IgD^-) B cells was significantly higher in patients with tongue SCC with no involved LNs (p = 0.033) and correlated inversely with the number of involved LNs. The frequency of CD24^hiCD38^hi B cells was significantly higher in non-metastatic LNs of patients with grade I compared to grade II (p = 0.016), and the percentage of CD5⁺ B cells decreased as tumors progressed from stage III to IV (p = 0.008). Our data show that in TDLNs of HNSCC, the frequency of B cells with atypical memory and regulatory phenotypes was significantly associated with good prognostic factors; however, their function remains to be investigated.

Potential role of regulatory B cells in immunological diseases

Regulatory B cells (Bregs) are immune-modulating cells that affect the immune system by producing cytokines or cellular interactions. These cells have immunomodulatory effects on the immune system by cytokine production. The abnormalities in Bregs could be involved in various disorders such as autoimmunity, chronic infectious disease, malignancies, allergies, and primary immunodeficiencies are immune-related scenarios. Ongoing investigation could disclose the biology and the exact phenotype of these cells and also the assigned mechanisms of action of each subset, as a result, potential therapeutic strategies for treating immune-related anomalies. In this review, we collect the findings of human and mouse Bregs and the therapeutic efforts to change the pathogenicity of these cells in diverse disease.

Granzyme B production by activated B cells derived from breast cancer-draining lymph nodes

B lymphocytes with regulatory or effector functions synthesize granzyme B (GZMB). We investigated the frequency and phenotype of GZMB-producing B cells in breast tumor-draining lymph nodes (TDLNs). Mononuclear cells were isolated from 48 axillary lymph nodes and were stimulated with anti-BCR (B cell receptor), recombinant interleukin (IL)-21 and CD40 L alone or in combination. Flow cytometry was used to evaluate the expression of GZMB in B cells, and in 4 samples the phenotype of GZMB⁺ B cells was determined. B cells produced GZMB only when stimulated with a combination of IL-21 and anti-BCR for at least 16 h. Adding CD40 L to IL-21 and anti-BCR stimuli resulted in lower GZMB production in B cells. A small fraction of B cells was able to produce perforin in all stimulation conditions, and the majority of GZMB⁺ B cells were perforin-negative. Both naïve (CD24^lowCD27^-) and active/memory (CD24^hiCD27⁺) B cells expressed GZMB. In patients with invasive ductal carcinoma, the frequency of GZMB⁺ B cells was significantly lower in metastatic compared to non-metastatic lymph nodes. The frequency of GZMB⁺ B cells did not significantly correlate with prognostic factors such as stage, tumor size or Her2 expression. In summary, a subpopulation of both naïve and memory B cells expressed GZMB in breast TDLNs. Our findings underscore the need to investigate the function of GZMB⁺ B cells in breast tumor immunity.

Importance of CD45RO+ tumor-infiltrating lymphocytes in post-operative survival of breast cancer patients

PURPOSE

In recent years, the prognostic/predictive significance of tumor infiltrating lymphocytes (TILs) has become a topic of interest. Here, we aimed to evaluate the prognostic significance of CD3+, CD8+, CD45RO+ and Foxp3+ TILs in breast cancer, as well as the relation of these markers to other clinicopathological features of this disease.

METHODS

FFPE tumor samples from 94 females with invasive ductal carcinoma of the breast were retrospectively selected and immunohistochemically assessed for CD3, CD8, CD45RO and Foxp3 expression. Digital photos were acquired from the center (CT) and invasive margins (IM) of the tumors, after which positive cells were counted using ImageJ software.

RESULTS

We found that greater infiltrations of target lymphocyte subpopulations were associated with TNM stage III, lymph node metastasis, high histological grade, ER negativity and HER2 positivity. The ratios of CD8+ cytotoxic T cells to CD3+, CD45RO+ and Foxp3+ TILs were found to be relatively higher in tumors exhibiting the aforementioned characteristics. In univariate survival analyses, CD8+ TILs in the IM and total CD45RO+ TILs were found to be significantly associated with overall survival (OS). Infiltration of CD45RO+ TILs in the CT and lymph node status were variables that significantly correlated with disease-free survival (DFS). Multiple Cox regression analyses revealed independent significant prognostic effects of total CD45RO+ TILs and lymph node status (HR of 3.24 and 3.19, respectively) in predicting OS. Infiltration of CD45RO+ TILs in the CT (HR 3.12) and lymph node status (HR 3.15) also exhibited significant prognostic effects on DFS.

CONCLUSION

From our data we conclude that CD45RO+ TILs serve as prognostic factors for predicting OS and DFS of breast cancer patients.