Tumor-infiltrating lymphocytes (TILs) are a valuable indicator of the immune microenvironment that plays the central role in new anticancer drugs. TILs has a strong prognostic role in triple negative breast cancer (TNBC). Little is known about his interaction with Androgen receptor (AR) and Forkhead box A1 (FOXA1). We analyzed the relationships between TIL levels, AR and FOXA1 expression and their clinical significance in TNBC patients. Further, we investigated their interaction with other biomarkers like programmed cell death ligand-1 (PD-L1), Breast Cancer Type 1 susceptibility protein (BRCA1), Poly [ADP-Ribose] Polymerase 1 (PARP1) and Na+/H+ Exchanger Regulatory Factor 1 (NHERF1). The expression of the proteins was evaluated by immunohistochemistry in 124 TNBC samples. TILs were performed adhering to International TILs Working Group 2014 criteria. Cox proportional hazards models were also used to identify risk factors associated with poor prognosis. Multivariate analysis identified TILs as independent prognostic factor of disease free survival (DFS) (p=0.045). A Kaplan-Meyer analysis revealed that the patients with high TILs had a better DFS compared to patients with low TILs (p=0.037), and the phenotypes TILs-/AR+ and TILs-/FOXA1- had a worse DFS (p=0.032, p=0.001 respectively). AR was associated with FOXA1 expression (p=0.007), and the tumors FOXA1+ presented low levels of TILs (p=0.028). A poor DFS was observed for AR+/FOXA1+ tumors compared to other TNBCs (p=0.0117). Low TILs score was associated with poor patients’ survival, and TILs level in combination with AR or FOXA1 expression affected patient’s clinical outcome. In addition, AR+/FOXA1+ phenotype identified a specific subgroup of TNBC patients with poor prognosis. These data may suggest new ways of therapeutic intervention to support current treatments.

The heterogeneity of tumor infiltrating lymphocytes is not well characterized in brain metastasis. To address this, we performed a targeted analysis of immune cell subsets in brain metastasis tissues to test which immunosuppressive routes are involved in brain metastasis. We performed multiplex immunofluorescence (mIF), using commercially available validated antibodies on twenty formalin-fixed paraffin embedded whole sections. We quantitated the subsets of immune cells utilizing a targeted panel of proteins including PanCK, CD8, CD4, VISTA and Iba1, and analyzed an average of 15000 cells per sample. We classified tumours as either high (>30%) or low (<30%) tumour infiltrating lymphocytes (TILs) and found that increased TILs density correlated with survival. We next sought out to phenotype these TILs using mIF. The tumours with low TILs (n=9) had significantly higher expression of the immune-checkpoint molecule VISTA in tumor cells (p<0.01) as well as in their microenvironment (p<0.001). Contrastingly, the brain metastatic tumours with high TILs (n=8) displayed higher levels of activated microglia, as measured by Iba1 expression. Low TILs-tumours displayed CD8+ T-cells that co-express VISTA (p<0.01) significantly more compared to high TILs group, where CD8+ T-cells significantly co-express Iba1 (p<0.05). Interestingly, no definite phenotypes of CD4+ subsets were observed. These results were supported by RNA analysis of a publicly available, independent cohort. In conclusion, our work contributes to a growing understanding of the immune surveillance escape routes active in brain metastasis.

There exists a variety of studies about tumor-infiltrating lymphocytes (TILs) in cervical cancer, but their prognostic value in correlation to the histopathological subtype was never investigated. Therefore, the aim of this study was to quantify TILs in a panel of 250 sporadic cervical cancers and investigate the correlation with cervical cancer subtype and patient survival. TIL levels were significantly increased in the subgroup of squamous cell carcinomas in comparison to adenocarcinomas. In squamous cell carcinomas, TIL infiltration shows a negative correlation to age, FIGO stage and to the histone protein modification H3K4me3. Moreover, in adenocarcinomas, it was positively correlated to p16 and to the glucocorticoid receptor and inversely correlated to the MDM2 protein and to H3K4me3. Interestingly, immune infiltration was an independent positive prognosticator for disease free survival (DFS) in patients with squamous cell carcinomas, those bearing tumors with the strongest TIL infiltration showing the better DFS. Altogether, the present study provides a differentiated overview of the relations between TIL levels and prognosis in patients with cervix squamous cell carcinomas vs patients with cervix adenocarcinomas.

With the rise of novel immunotherapies able to stimulate the antitumor immune response, increasing literature data concerning the immunogenicity of breast cancer have been published in recent years. Numerous clinical studies have been conducted in order to identify novel biomarkers that could reflect the immunogenicity of BC and predict response to immunotherapy. In this regard, TILs have emerged as an important immunological biomarker related to the antitumor immune re-sponse in BC. TILs are more frequently observed in triple-negative breast cancer and HER2+ sub-types where increased TIL levels have been linked to better response to neoadjuvant chemotherapy and with improved survival. PD-L1 is a type 1 transmembrane protein ligand expressed on T lymphocytes, B lymphocytes and antigen-presenting cells and is considered a key inhibitory checkpoint involved in cancer immune regulation. PD-L1 immunohistochemical expression in breast cancer is observed in about 10–30% of cases and is extremely variable based on tumor stage and molecular subtypes . In detail, TNBC shows the highest percentages of PD-L1 positivity, followed by HER2+ tumors. On the other hand, PD-L1 is rarely expressed (0-10% of cases) in hormone-receptor positive BC. The prognostic role of PD-L1 expression in BC is still controversial since different immunohistochemistry (IHC) clones, cut-off points and scoring systems have been utilized across published studies. In the present paper an extensive review on the current knowledge of immune landscape of BC is provided. In detail TILS and PD-L1 expression across different BC subtypes is discussed also providing a guide for their pathological assessment and reporting.

Intratumoral immune cytolytic activity (CYT), measured as the geometric mean of the expression of Granzyme-A (GZMA) and Perforin-1 (PRF1), has emerged as a critical factor in cancer immunotherapy, with significant implications for patient prognosis and treatment outcomes. Here, we review how different immune checkpoint pathways, the composition of Tumor Microenvironment (TME), antigen presentation and metabolic pathways, all regulate CYT. We also discuss the various methods through which CYT can be assessed. The detection and analysis of tumor-infiltrating lymphocytes using flow cytometry or immunohistochemistry provide important information on the immune cell populations within the TME. Gene expression profiling and spatial analysis techniques, such as multiplex immunofluorescence and imaging mass cytometry, allow researchers to study CYT in the context of the TME. We further report the significant clinical implications that CYT has, as its increased levels are associated with positive clinical outcomes and a favorable prognosis. Moreover, CYT can be used as a prognostic biomarker and aid in patient stratification. Measuring CYT through different methods offers promising paths for improving treatment responses. Overall, we highlight that the understanding and modulation of CYT levels is critical for improving cancer immunotherapy. Research into CYT and the factors that influence it has the potential to transform cancer treatment and improve patient outcomes.