Antigen/HLA-agnostic strategies for Characterizing Tumor-responsive T cell receptors in PDAC patients via single-cell sequencing and autologous organoid application

Characterization of tumor-responsive T cell receptors (TCRs) is a critical step in personalized TCR-T cell therapy, and remains challenging for pancreatic ductal adenocarcinoma (PDAC). Here we report a proof-of-concept study to identify and validate antitumor TCRs in two representative PDAC patients using ultradeep single-cell TCR/RNA sequencing and autologous organoids, and reveal the phenotypic dynamics of TCR repertoire in different T cell expansions from the same patient. We first performed comparative sequencing on freshly harvested peripheral blood mononuclear cells (PBMCs) and uncultured tumor infiltrating lymphocytes (TILs), followed by reactivity tests of TIL-enriched TCRs with autologous organoids, in which two tumor-responsive TCRs were successfully characterized and the corresponding TILs were mostly tissue-resident memory-like T cells, and partially expressed both naïve and exhausted T cell markers. For the PDAC patient without high-quality TILs, PBMCs were cultured with neoantigen peptide (KRASG12D), organoids, or anti-CD3 antibody in presence, and experienced extensive clonal expansions within ten days. All derived PBMCs were sequenced in parallel (>82,000 cells), and TCRs enriched in both peptide- and organoid-experienced, but not anti-CD3-treated CD8 T cells, were assessed for their reactivity to antigen-presenting cells (APCs) and organoids, in which three neoantigen-reactive TCRs were identified as tumor-responsive, and the corresponding T cells were characterized by mixed transcriptional signatures including but not limited to typical exhausted T cell markers. Together, our study revealed that the combination of ultradeep single-cell sequencing and organoid techniques enabled rapid characterization of tumor-responsive TCRs for developing practical personalized TCR-T therapy in an antigen/human leukocyte antigen (HLA)-agnostic manner.

Adoptive T cell therapy for ovarian cancer

Although ovarian cancer patients typically respond to standard of care therapies, including chemotherapy and DNA repair inhibitors, the majority of tumors recur highlighting the need for alternative therapies. Ovarian cancer is an immunogenic cancer in which the accumulation of tumor infiltrating lymphocytes (TILs), particularly T cells, is associated with better patient outcome. Thus, harnessing the immune system through passive administration of T cells, a process called adoptive cell therapy (ACT), is a promising therapeutic option for the treatment of ovarian cancer. There are multiple routes by which tumor-specific T cell products can be generated. Dendritic cell cancer vaccines can be administered to the patients to induce or bolster T cell responses against tumor antigens or be utilized ex vivo to prime T cells against tumor antigens; these T cells can then be prepared for infusion. ACT protocols can also utilize naturally-occurring tumor-reactive T cells isolated from a patient tumor, known as TILs, as these cells often are heterogeneous in composition and antigen specificity with patient-specific cancer recognition. Alternatively, T cells may be sourced from the peripheral blood, including those that are genetically modified to express a tumor antigen-specific T cell receptor (TCR) or chimeric antigen receptor (CAR) to redirect their specificity and promote their activity against tumor cells expressing the target tumor antigen. Here, we review current ACT strategies for ovarian cancer and provide insights into advancing ACT therapy strategies for the treatment of ovarian cancer.

Systemic inflammation, the peripheral blood transcriptome and primary melanoma

Peripheral blood transcriptomes from 383 newly-diagnosed melanoma patients were subjected to differential gene expression analysis. The hypotheses were that impaired systemic immunity is associated with poorer prognosis (thicker tumors and fewer tumor infiltrating lymphocytes (TILs)) and evidence of systemic inflammation (high-sensitivity C-reactive protein (hsCRP) and fibrinogen levels). Higher fibrinogen levels were associated with thicker primaries. In single gene analysis hsCRP levels were significantly associated with higher blood CD274 expression, (coding for PD-L1), but each was independently prognostic, with hsCRP associated with increased mortality, and higher CD274 protective, independent of age. Pathway analysis identified downregulation of immune cell signalling pathways in the blood of people with thicker tumors and notable upregulation of STAT1 in people with brisk TILs. Transcriptomic data provided evidence for increased NFB signalling with higher inflammatory markers but with reduction in expression of HLA class II molecules and higher CD274 suggesting that aberrant systemic inflammation is a significant mediator of reduced immune function in melanoma. In summary, transcriptomic data revealed evidence of reduced immune function in patients with thicker tumors and fewer TILs, at diagnosis. Inflammatory markers were associated with thicker primaries and independently with death from melanoma suggesting that systemic inflammation contributes to that reduced immune function.

VISTA/CTLA4/PD1 coexpression on tumor cells confers a favorable immune microenvironment and better prognosis in high-grade serous ovarian carcinoma

Introduction

Immunotherapy by blocking immune checkpoints programmed death/ligand (PD1/PDL1) and cytotoxic T-lymphocyte-associated protein 4(CTLA4) has emerged as new therapeutic targets in cancer. However, their efficacy has been limited due to resistance. A new- checkpoint V-domain Ig-containing suppressor of T cell activation (VISTA) has appeared, but the use of its inhibition effect in combination with antibodies targeting PDL1/PD1and CTLA4 has not been reported in ovarian cancer.

Methods

In this study, we investigated the expressions of VISTA, CTLA4, and PDL1 using immunohistochemistry (IHC)on 135 Formalin-Fixed Paraffin-Embedded (FFPE)tissue samples of High-grade serous carcinoma (HGSOC). VISTA, CTLA4, PDL1, PD1, CD8, CD4, and FOXP3 mRNA extracted from 429 patients with ovarian cancer in the Cancer Genome Atlas (TCGA) database was included as a validation cohort. Correlations between these checkpoints, tumor-infiltrating- lymphocytes (TILs), and survival were analyzed.

Results and discussion

CTLA4 was detectable in 87.3% of samples, VISTA in 64.7%, PD1 in 56.7%, and PDL1 in 48.1%. PDL1 was the only tested protein associated with an advanced stage (p=0.05). VISTA was associated with PDL1, PD1, and CTLA4 expressions (p=0.005, p=0.001, p=0.008, respectively), consistent with mRNA level analysis from the TCGA database. Univariate analyses showed only VISTA expression (p=0.04) correlated with overall survival (OS). Multivariate analyses showed that VISTA expression (p=0.01) and the coexpression of VISTA+/CTLA4+/PD1+ (p=0.05) were associated with better OS independently of the clinicopathological features. Kaplan-Meier analysis showed that the coexpression of the VISTA+/CTLA4+/PDL1+ and VISTA+/CTLA4+/PD1+ checkpoints on tumor cells (TCs)were associated with OS (p=0.02 and p<0.001; respectively). VISTA+/CTLA4+/PD1+ in TCs and CD4+/CD8+TILswere associated with better 2-yer OS. This correlation may refer to the role of VISTA as a receptor in the TCs and not in the immune cells. Thus, targeting combination therapy blocking VISTA, CTLA4, and PD1 could be a novel and attractive strategy for HGSOC treatment, considering the ambivalent role of VISTA in the HGSOC tumor cells.

Prognostic value and distribution pattern of tumor infiltrating lymphocytes and their subsets in distant metastases of advanced breast cancer

BACKGROUND

There are significant correlations between the levels of tumor infiltrating lymphocytes (TILs) and the prognosis of primary breast cancer. While little is known about immunological mechanisms in the distant metastasis of advanced breast cancer.

PATIENTS AND METHODS

A total of 106 patients with advanced metastatic breast cancer were enrolled in this study between 2016 and 2022. Hematoxylin and eosin staining and immunohistochemistry were used to assess the densities of stromal TILs (sTILs), intratumoral TILs (iTILs) and invasive marginal TILs (imTILs) and CD4+, CD8+, CD20+, FOXP3+ TILs in the primary tumor and metastasis (bone, lung, liver, and distant lymph node) of advanced breast cancer.

RESULTS

Higher levels of sTILs at metastatic sites were associated with better progression-free survival (PFS), postmetastasis survival (PMS) and overall survival (OS) (p = .026, .001 and .005, respectively). The levels of iTILs were significantly lower than those of sTILs and imTILs in both primary tumor (p< .001, both) and metastasis (p< .001, both). The level of CD4+ T cells was higher than those of CD8+ T cells and CD20+ B cells in both primary tumor (p < .001) and metastasis (p < .001). The levels of sTILs (p=0. 001) and imTILs (p< .001) in the primary tumor were generally higher than those in the metastasis.

CONCLUSION

The levels of TILs and their subsets can predict the survival and prognosis of patients with advanced breast cancer. The distributions of TILs and their subsets are similar between the primary tumor and metastasis. The metastases have a lower degree of lymphocytes infiltration than its corresponding primary tumor.

Expression of cell surface zinc transporter LIV1 in triple negative breast cancer is an indicator of poor prognosis and therapy failure

Triple negative breast cancers (TNBC) are an aggressive molecular subtype of breast carcinoma (BC) identified by the lack of receptor expression for estrogen, progesterone, & human epidermal growth factor receptor-2. Lack of tangible drug targets warrants further research in TNBC. LIV1, is a zinc (Zn) transporter known to be overexpressed in few cancer types including BCs. Recently, in the United States of America, FDA approved the use of a new drug targeting LIV1, antibody drug conjugate SGN-LIV1A for treatment of TNBC patients. Though LIV1 also has a role in modulating immune cells by its differential transport of Zn, a correlation between the tumor cell expression of LIV1 and immune cell infiltrations were scantily reported. Further adequate baseline data on LIV1 expression in other populations have not been documented. Our objective was to screen a large Indian cohort of TNBC patient samples for LIV1, categorize the immune cell infiltration using CD4/CD8 expression and correlate the findings with therapy outcomes. Further, we also investigated for LIV1 expression in matched samples of primary & secondary tumors; pre & postchemotherapy in TNBC patients. Results showed an elevated expression of LIV1 in TNBC samples as compared to adjacent normal, the mean Q scores being 183.06 ± 6.39 and 120.78 ± 7.37 (p < 0.0001), respectively. Similarly, LIV1 levels were elevated in secondary tumors than primary & in patient samples postchemotherapy as compared to naïve. In the TNBC cohort, using automated method, cell morphology parameters were computed and analysis showed LIV1 levels were elevated in grade 3 TNBC samples presenting with altered cell morphology parameters namely cell size, cell perimeter, & nucleus size. Thus indicating LIV1 expressing TNBC samples portrayed an aggressive phenotype. Finally, TNBC patients with 3+ staining intensity showed poor survival (4.44 year) as compared to patients with 2+ LIV1 expression (5.47 year), emphasizing that LIV1 expression is a poor prognostic factor in TNBC. In conclusion, the study reports elevated expression of LIV1 in a large Indian TNBC cohort; high expression is a poor prognostic factor and correlated with aggressive disease and indicating the need for LIV1 targeted therapies.

Tumor immunity: A brief overview of tumor‑infiltrating immune cells and research advances into tumor‑infiltrating lymphocytes in gynecological malignancies (Review)

Tumor immunity is a promising topic in the area of cancer therapy. The 'soil' function of the tumor microenvironment (TME) for tumor growth has attracted wide attention from scientists. Tumor-infiltrating immune cells in the TME, especially the tumor-infiltrating lymphocytes (TILs), serve a key role in cancer. Firstly, relevant literature was searched in the PubMed and Web of Science databases with the following key words: 'Tumor microenvironment'; 'TME'; 'tumor-infiltrating immunity cells'; 'gynecologic malignancies'; 'the adoptive cell therapy (ACT) of TILs'; and 'TIL-ACT' (https://pubmed.ncbi.nlm.nih.gov/). According to the title and abstract of the articles, relevant items were screened out in the preliminary screening. The most relevant selected items were of two types: All kinds of tumor-infiltrating immune cells; and advanced research on TILs in gynecological malignancies. The results showed that the subsets of TILs were various and complex, while each subpopulation influenced each other and their effects on tumor prognosis were diverse. Moreover, the related research and clinical trials on TILs were mostly concentrated in melanoma and breast cancer, but relatively few focused on gynecological tumors. In conclusion, the present review summarized the biological classification of TILs and the mechanisms of their involvement in the regulation of the immune microenvironment, and subsequently analyzed the development of tumor immunotherapy for TILs. Collectively, the present review provides ideas for the current treatment dilemma of gynecological tumor immune checkpoints, such as adverse reactions, safety, personal specificity and efficacy.

Emerging measurements for tumor-infiltrating lymphocytes in breast cancer

Tumor-infiltrating lymphocytes are a general term for lymphocytes or immune cells infiltrating the tumor microenvironment. Numerous studies have demonstrated tumor-infiltrating lymphocytes to be robust prognostic and predictive biomarkers in breast cancer. Recently, immune checkpoint inhibitors, which directly target tumor-infiltrating lymphocytes, have become part of standard of care treatment for triple-negative breast cancer. Surprisingly, tumor-infiltrating lymphocytes quantified by conventional methods do not predict response to immune checkpoint inhibitors, which highlights the heterogeneity of tumor-infiltrating lymphocytes and the complexity of the immune network in the tumor microenvironment. Tumor-infiltrating lymphocytes are composed of diverse immune cell populations, including cytotoxic CD8-positive T lymphocytes, B cells and myeloid cells. Traditionally, tumor-infiltrating lymphocytes in tumor stroma have been evaluated by histology. However, the standardization of this approach is limited, necessitating the use of various novel technologies to elucidate the heterogeneity in the tumor microenvironment. This review outlines the evaluation methods for tumor-infiltrating lymphocytes from conventional pathological approaches that evaluate intratumoral and stromal tumor-infiltrating lymphocytes such as immunohistochemistry, to the more recent advancements in computer tissue imaging using artificial intelligence, flow cytometry sorting and multi-omics analyses using high-throughput assays to estimate tumor-infiltrating lymphocytes from bulk tumor using immune signatures or deconvolution tools. We also discuss higher resolution technologies that enable the analysis of tumor-infiltrating lymphocytes heterogeneity such as single-cell analysis and spatial transcriptomics. As we approach the era of personalized medicine, it is important for clinicians to understand these technologies.

HER2-low and tumor infiltrating lymphocytes in triple-negative breast cancer: Are they connected?

Most patients with triple-negative breast cancer (TNBC) are not candidates for targeted therapy, leaving chemotherapy as the primary treatment option. Recently, immunotherapy has demonstrated promising results in TNBC, due to its immunogenicity. In addition, a novel antibody-drug conjugate, namely, trastuzumab-deruxtecan, has shown effectiveness in TNBC patients with low-HER2 expression (HER2-low). These novel treatment options raise the question about the potential association between the density of stromal tumor-infiltrating lymphocytes (sTILs) and the level of HER2 expression. We aimed to evaluate the association between the level of HER2 expression (HER2-low versus HER2-0) and density of sTILs in TNBC patients, and how they impact the response to neoadjuvant chemotherapy (NAC). This was a retrospective multicenter study including all TNBC patients diagnosed between 2018 and 2022. Central pathology review included sTILs percentages and level of HER2 expression. Tumors were reclassified as either HER2-0 (HER2 IHC 0) or HER2-low (IHC 1 + or 2 + with negative reflex test). Various clinicopathologic characteristics, including sTILs density, and response to NAC were compared between HER2-0 and HER2-low cases. In total, 753 TNBC patients were included in this study, of which 292 patients received NAC. Interobserver agreement between the original pathology report and central review was moderate (77% had the same IHC status after reclassification in either HER2-0 or HER2-low; k = 0.45). HER2-low TNBC represented about one third (36%) of the tumors. No significant difference in sTILs density or complete pathologic response rate was found between HER2-0 and HER2-low cases (p = 0.476 and p = 0.339, respectively). The density of sTILs (≥ 10% sTILs vs. < 10%) was independently associated with achieving a pCR (p = 0.011). In conclusion, no significant association was found between HER2-low status and density of sTILs nor response to NAC. Nonetheless, sTILs could be an independent biomarker for predicting NAC response in TNBC patients.

CD39+ tumor infiltrating T cells from colorectal cancers exhibit dysfunctional phenotype

Recent studies revealed that CD39 was highly expressed in tumor-specific CD4+ tumor infiltrating lymphocytes (TILs). However, the divergent function of CD39+ T cells remains to be elucidated in colorectal cancer (CRC). In this study, T cells from CRC patients and tumor-bearing mice were isolated to evaluate the function of CD39 in T cells. We found that CD39 was elevated in intratumoral T cells from CRC patients, and negatively correlated with cytokine secretion capacity. T cell activation induced CD39 expression, and CD39+ T cells produced more IFN-γ in response to CRC tumor antigens. In addition, CD39+ T cells in the spleens of tumor-bearing mice exhibited a stronger anti-tumor activity in vitro than CD39- T cells, but there was no significant difference in the anti-tumor activities between CD39- TILs and CD39+ TILs. Moreover, we found that CD39+ T cells expressed higher checkpoint molecules and contained a higher proportion of Treg cells than CD39- T cells, suggesting that CD39+ T cells may be correlated with an immunosuppressive phenotype. And CD39 expression on T cells could convert pro-inflammatory eATP to immunosuppressive eADO. However, both T cells from the vaccinated-wild-type mice and CD39-/- mice could recognize and eliminate tumor cells in vitro, and adoptive transfer of these T cells resulted in tumor growth inhibition in tumor-bearing mice. In conclusion, our study revealed the divergent functions of CD39+ T cells, which were reactive to tumor antigen but exhibited a dysfunctional phenotype.

Ten-year clinical outcome, toxicity and compliance of dose-dense sequential adjuvant administration of cyclophosphamide & epirubicin followed by docetaxel in patients with early breast cancer: A hellenic cooperative oncology group observational study (HE 10/10) with concurrent investigation of significance of tumor infiltrating lymphocytes

BACKGROUND

Dose-dense sequential (dds) chemotherapy has changed the clinical outcome of patients with early breast cancer (BC). To investigate the impact of dose intensity (DI) in the adjuvant setting of BC, this observational trial (HE 10/10) was conducted assessing the long-term survival outcome, safety and toxicity of a currently widely used chemotherapeutic regimen. In addition, the prognostic significance of tumor infiltrating lymphocytes (TILs) and infiltrating CD8+ lymphocytes were also evaluated in the same cohort.

PATIENTS AND METHODS

Totally, 1054 patients were prospectively enrolled in the current study with 1024 patients being eligible, while adequate tissue was available for 596 of them. TILs, CD8+ lymphocytes in intratumoral areas in contact with malignant cells (iCD8), CD8+ lymphocytes in tumor stroma (sCD8) as well as the total number of CD8+ lymphocytes within the tumor area (total CD8) were assessed by immunohistochemistry.

RESULTS

Within a median follow-up of 125.18 months, a total of 200 disease-free survival (DFS) events (19.5%) were reported. Importantly, the 10-year DFS and OS rates were 78.4% (95% CI 75.0-81.5) and 81.7% (95% CI 79.0-84.1), respectively. Interestingly, higher CD8+ T cells as well as TILs in the tumor microenvironment were associated with an improved long-term survival outcome.

CONCLUSIONS

In conclusion, this study confirms the significance of dds adjuvant chemotherapeutic regimen in terms of long-term survival outcome, safety and toxicity as well as the prognostic significance of TILs and infiltrating CD8+ lymphocytes in BC patients with early-stage disease.

CD137+ tumor infiltrating lymphocytes predicts ovarian cancer survival

OBJECTIVE

Ovarian cancer (OC) is the leading cause of death from gynecologic malignancy in the United States, and biomarkers of patient outcomes are limited. Data using immunohistochemical (IHC) analysis are mixed regarding whether and which tumor infiltrating lymphocytes (TILs) impact survival, and IHC does not adequately quantify rare cell populations, including CD137+ (4-1BB) tumor-reactive TILs. Our study investigates if a higher percentage of CD3+ CD137+ TILs is associated with improved overall survival (OS) in OC.

METHODS

Flow cytometry was performed on viably banked OC digests. Chart review and statistical analysis were performed. Forty-seven patients were included, 40 of whom were diagnosed with high-grade serous ovarian carcinoma (HGSOC), papillary serous carcinoma, or undifferentiated histology.

RESULTS

A high percentage of CD3+ CD137+ TILs correlated with improved OS (n = 40, r = 0.48, P = 0.0016). Subjects were divided into CD3+ CD137+ TIL high and low groups by the median. Subjects with high CD3+CD137+ TIL frequencies (>9.6%) had longer OS (Wilcoxon rank-sum test; P = 0.0032) and improved OS (logrank test; P = 0.007). Differences in CD3+ or CD3+ CD8+ TILs did not impact survival. CD3+ CD137+ TILs were predictive of OS regardless of germline mutation or debulking status. Analysis of subgroups including late stage HGSOC and late stage HGSOC with primary optimal cytoreduction indicated CD3+ CD137+ TILs correlated with improved OS after adjusting for age and PARP inhibitor use (P = 0.034 and P = 0.016, respectively).

CONCLUSIONS

Prevalence of CD3+ CD137+ TILs in digested OC specimens is associated with improved OS, while general TIL markers are not. CD137 has the potential to be a novel biomarker for survival in OC.

Experimental and clinical evidence in favour of an effective immune stimulation in ER-positive, endocrine-dependent metastatic breast cancer

In ER+ breast cancer, usually seen as the low immunogenic type, the main mechanisms favouring the immune response or tumour growth and immune evasion in the tumour microenvironment (TME) have been examined. The principal implications of targeting the oestrogen-mediated pathways were also considered. Recent experimental findings point out that anti-oestrogens contribute to the reversion of the immunosuppressive TME. Moreover, some preliminary clinical data with the hormone-immunotherapy association in a metastatic setting support the notion that the reversion of immune suppression in TME is likely favoured by the G0-G1 state induced by anti-oestrogens. Following immune stimulation, the reverted immune suppression allows the boosting of the effector cells of the innate and adaptive immune response. This suggests that ER+ breast cancer is a molecular subtype where a successful active immune manipulation can be attained. If this is confirmed by a prospective multicentre trial, which is expected in light of the provided evidence, the proposed hormone immunotherapy can also be tested in the adjuvant setting. Furthermore, the different rationale suggests a synergistic activity of our proposed immunotherapy with the currently recommended regimen consisting of antioestrogens combined with cyclin kinase inhibitors. Overall, this lays the foundation for a shift in clinical practice within this most prevalent molecular subtype of breast cancer.

Clinical impact of heterogeneously distributed tumor-infiltrating lymphocytes on the prognosis of colorectal cancer

Background

Tumor-infiltrating lymphocytes (TILs) exist in various malignancies, and have been viewed as a promising biomarker to predict the efficacy and outcome of treatment. However, the marked inter- and intra-tumor heterogeneity of TILs has resulted in some confusion regarding their impact on the prognosis of colorectal cancer (CRC).

Methods

In this study, 78 CRC patients were enrolled and the CD3+ and CD8+ TILs densities at the tumor center (TC), the invasive margin (IM) and the tumor stroma (TS) were assessed by immunohistochemical staining. Their associations with clinicopathological features and progression free survival (PFS) were analyzed to evaluate the predictive and prognostic values of TILs.

Results

TILs were mainly distributed along the invasive margin. High density of TILs in tumor center and invasive margin was associated with smaller tumor size (CD3+TILsIM), reduced tumor invasion (CD3+TILsIM), absence of lymph node metastasis (CD3+TILsIM and CD8+TILsTC), earlier stage (CD3+TILsIM and CD8+TILsIM), and lower tumor grade (CD3+TILsIM and CD8+TILsTC). However, stromal TILs were not associated with any clinicopathological features. Kaplan-Meier survival analysis revealed that high densities of TILs always correlated with prolonged patient survival. The pathological N stage, CD3+ TILsIM and CD8+ TILsTC were found to be independent prognostic indicators. Additionally, early-stage CRC patients who developed recurrence after surgery, showed a higher CD3+/CD8+ TILs ratio in invasive margin. In the present study, it was clarified that CD3+ and CD8+ TILs were heterogeneously distributed in tumor tissues of CRC. The increase in intratumoral and peritumoral TILs had been shown to be strongly predictive of improved clinical outcome. More importantly, the immune signatures enabled to stratify early-stage CRC patients with high risk of recurrence, highlighting the prognostic power of TILs.

Targeting the activin receptor 1C on CD4+ T cells for cancer immunotherapy

Activins, members of the TGF-beta superfamily, have been isolated and identified in the endocrine system, but have not been substantially investigated in the context of the immune system and endocrine-unrelated cancers. Here, we demonstrated that tumor-bearing mice had elevated systemic activin levels, which correlated directly with tumor burden. Likewise, cancer patients have elevated plasma activin levels compared to healthy controls. We observed that both tumor and immune cells could be sources of activins. Importantly, our in vitro studies suggest that activins promote differentiation of naïve CD4+ cells into Foxp3-expressing induced regulatory T cells (Tregs), particularly when TGF-beta was limited in the culture medium. Database and qRT-PCR analysis of sorted major immune cell subsets in mice revealed that activin receptor 1c (ActRIC) was uniquely expressed on Tregs and that both ActRIC and ActRIIB (activin receptor 2b) were highly upregulated during iTreg differentiation. ActRIC-deficient naïve CD4+ cells were found to be defective in iTreg generation both in vitro and in vivo. Treg suppression assays were also performed, and ActRIC deficiency did not change the function or stability of iTregs. Mice lacking ActRIC or mice treated with monoclonal anti-ActRIC antibody were more resistant to tumor progression than wild-type controls. This phenotype was correlated with reduced expression of Foxp3 in CD4+ cells in the tumor microenvironment. In light of the information presented above, blocking activin-ActRIC signaling is a promising and disease-specific strategy to impede the accumulation of immunosuppressive iTregs in cancer. Therefore, it is a potential candidate for cancer immunotherapy.

Clinicopathological features and prognostic analysis of HER2 low and fibrotic focus in HER2-negative breast cancer

OBJECTIVE

The aim of this study is to evaluate the clinicopathological features and prognostic significance of HER2 low, fibrotic focus (FF), and tumor-infiltrating lymphocytes (TILs) in patients with HER2-negative breast cancer.

METHODS

We retrospectively reviewed the data of 293 patients with HER2-negative, stage I-II, invasive breast cancer of non-specific types. The HER2-negative cases were classified into HER2 low and HER2 0. Digital analysis of hematoxylin-eosin stained whole slide images was used to evaluate the FF expression. TILs were also evaluated using the Whole Slide Image. Furthermore, the association between HER2 low, FF, and TILs as well as their prognostic significance were analyzed.

RESULTS

The study cohort included 178 cases (60.8%) with HER2 low and 115 cases (39.2%) with HER2 0. Older age, lower Nottingham histological grade (NHG), estrogen receptor (ER) positivity, progesterone receptor (PR) positivity, and hormone receptor (HR) positivity were all associated with HER2 low. FF was correlated with older age, intermediate and low NHG, vascular invasion, HR positivity, HER2 low status, high Ki67 expression, and low TILs. Univariate survival analysis showed that FF was significantly associated with shorter progression-free survival (PFS). Stratified analysis indicated that in the HR-negative and HR-positive groups, HER2 status and TILs did not affect PFS. DFS was longer in patients without FF compared to those with FF in the HR-positive (hazard ratio [HR] = 0.313) and HER2 low (HR = 0.272) groups. DFS was also significantly longer in patients without FF compared to those with FF in the HR-negative (HR = 0.069) and HER2 0 groups (HR = 0.129).

CONCLUSION

The results indicated that the HER2 low status and the TILs expression did not impact prognosis. However, patients with FF exhibited distinct biological characteristics and prognostic significance, particularly in the HR-negative and HER2 0 groups. This provides a rationale for accurate diagnosis and treatment of HER2-negative breast cancer.

Impact of Mutations in Subunit Genes of the Mammalian SWI/SNF Complex on Immunological Tumor Microenvironment

BACKGROUND/AIM

Recently, inactivating somatic mutations of SWI/SNF chromatin-remodeling genes in cancers have been reported. However, few studies have been performed regarding the immunological analysis of the tumor microenvironment (TME) in chromatin remodeling complex gene-mutated tumors. In the present study, we identified cancer patients harboring various mammalian SWI/SNF complex mutations and investigated the immunological features in those mutated cancers.

PATIENTS AND METHODS

Cancer patients harboring any type of chromatin remodeling complex gene mutation were selected and clinicopathological features were compared between chromatin remodeling complex gene expression-low and expression-high groups. Specifically, expression levels of immune response-associated genes and cancer-associated genes were compared between the SMARCA4 expression-low and expression-high groups using volcano plot analysis.

RESULTS

Among cancers harboring PBRM1, SAMRACA4 and ARID2 gene mutations, T-cell marker and mature B-cell marker genes were up-regulated in the tumor. Specifically, T-cell effector genes (CD8B, CD40LG), central memory marker genes (CD27, CCR7) and mature B-cell marker genes (CD20, CD38, CD79 and IRF4) were up-regulated, and cancer-associated genes including MYB, MYC and AURKB genes were down-regulated in the SMARCA4 expression-low group. Remarkably, heatmap of gene expression and immunohistochemistry (IHC) data demonstrated that the tertiary lymphoid structure (TLS) gene signature of mature B cells was up-regulated in SMACA4 gene-mutated stomach cancers.

CONCLUSION

These results suggest that immune tumor microenvironment status, such as mature B cell recruitment featuring the TLS gene signature and immune activation mediated by cancer signal down-regulation, might contribute to the classification of SMARCA4 gene-mutated tumors as immune checkpoint blockade therapy-sensitive target tumors.

Evaluation of immune density, PD-L1, and CXCR4 expressions in metaplastic breast carcinoma to predict potential immunotherapy benefit

Metaplastic breast carcinoma (MBC) -rare but fatal subtype of invasive breast carcinomas- provides limited benefit from conventional triple-negative breast carcinoma chemotherapy. We aimed to determine the immune density of this tumor and to evaluate of programmed death-ligand 1 (PD-L1) and chemokine receptor type 4 (CXCR4) expressions to determine whether it would benefit from immunotherapy. Clinicopathological characteristics of 85 patients diagnosed as MBC between 1997 and 2017 were retrospectively assessed. We evaluated the immunohistochemical expression of PD-L1 and CXCR4, and the extent of tumour infiltrating lymphocytes (TILs), with survival data. TILs groups were statistically significantly associated with lymph node status, histological subtype, squamous component, local recurrence and/or systemic metastasis, and disease-related deaths (p < 0.05). PD-L1 positivity in immune cells (ICs) has a statistically significant relationship with the presence of squamous component (p = 0.011) and HER2 positivity (p = 0.031). PD-L1 positivity in tumor cells (TCs) was found to be significantly more frequent in high-TILs density (p = 0.003). PD-L1 combined positive score was significantly associated with the tumors containing high-TILs density (p = 0.012) and squamous component (p = 0.035). Disease-free and disease-specific survival rates were found to be longer for the cases displaying PD-L1 positivity in ICs; and also PD-L1 positivity in ICs was found to be an independent prognostic factor. When the expression of CXCR4 was compared with clinicopathological and survival parameters, no statistically significant association was found (p > 0.05). Based on the results of this retrospective study, PD-L1 and TILs appear to be prognostic. This study provides rationale for further studies to determine whether a subset of patients with metaplastic breast cancer could derive a meaningful benefit from immune-targeting therapies.

Prognostic value of Hematoxylin and eosin staining tumor-infiltrating lymphocytes (H&E-TILs) in patients with esophageal squamous cell carcinoma treated with chemoradiotherapy

BACKGROUND

Tumor-infiltrating lymphocytes (TILs) by routine hematoxylin and eosin staining (H&E-TILs) are a robust prognostic biomarker in various cancers. However, the role of H&E-TILs in esophageal squamous cell carcinoma (ESCC) treated with concurrent chemoradiotherapy (CCRT) has not been reported. The purpose of this study was to assess the prognostic value of H&E-TILs in ESCC treated with CCRT.

METHODS

The clinical data of 160 patients with ESCC treated with CCRT in our center between Jan. 2014 and Dec. 2021 were collected and retrospectively reviewed, and propensity score matching (PSM) analyses were performed. The H&E-TILs sections before CCRT were reassessed by two experienced pathologists independently. The H&E-TILs sections were classified into a positive group (+, > 10%) and a negative group (-, ≤ 10%) using 10% as the cutoff. The effects of H&E-TILs on overall survival (OS), progression-free survival (PFS), distant metastasis-free survival (DMFS), and locoregional recurrence-free survival (LRFS) were explored using the Kaplan‒Meier method, and the log-rank test was used to test the differences. Multivariable analysis was performed using the Cox proportion hazards model.

RESULTS

The short-term response to CCRT and the OS (P < 0.001), DMFS (P = 0.001), and LRFS (P < 0.001) rates were significantly different between the H&E-TILs (+) and H&E-TILs (-) groups. Subgroup analysis showed that H&E-TILs(+) with CR + PR group had a longer survival than H&E-TILs(-) with CR + PR, H&E-TILs(+) with SD + PD and H&E-TILs(-) with SD + PD group, respectively(P < 0.001). Furthermore, based on TCGA data, patients in the high TILs group had a better prognosis than those in the low TILs group. Multivariate analyses indicated that H&E-TILs and the short-term response to CCRT were the only two independent factors affecting OS, PFS, DMFS, and LRFS simultaneously, and H&E-TILs expression was associated with an even better prognosis for those patients with CR + PR.

CONCLUSIONS

H&E-TILs may be an effective and beneficial prognostic biomarker for ESCC patients treated with CCRT. Patients with H&E-TILs (+) with PR + CR would achieve excellent survival. Further prospective studies are required to validate the conclusions.

Evaluation of tumor-infiltrating lymphocytes, PD-L1, and PIK3CA mutations and association with prognosis in HER2-positive early stage breast cancer

BACKGROUND

Tumor-infiltrating lymphocytes (TILs) have predictive and prognostic potential in HER2-positive breast cancer (HER2+ BC). Programmed death-ligand 1 (PD-L1) is an immune checkpoint protein, with important roles in the tumor microenvironment, possibly in both tumor and immune cells (ICs), providing rationale for targeting with immune-checkpoint therapy. PIK3CA mutations are oncogenic, activating mutations, which are also of relevance in breast cancer. Herein, we investigate the frequency of TILs, PD-L1 and PIK3CA mutations, and whether these factors influence outcome, in early HER2+ BC.

MATERIALS AND METHODS

Stromal TILs (sTILs) and PD-L1 expressions were assessed using full tumor-sections and TMA, respectively, from 236 patients with HER2+ BC. TILs were assessed, according to a standardized method, as continuous measurement and according to three predefined categories: low (0-10%), intermediate (11-59%), and high (60-100%). PD-L1 immunohistochemistry (Ventana SP263) was evaluated and positivity defined as ≥1% expression in tumor and ICs. PIK3CA mutations (exons 9 and 20) were determined by pyrosequencing.

RESULTS

Fourteen percent of patients had high sTILs and 25% had a PIK3CA mutation. PD-L1 expression was more frequent in ICs (68%) than tumor cells (24%). Patients with low sTILs had a significantly worse overall survival (multivariate: HR 2.80; 95% CI 1.36-5.78; p = .02).

DISCUSSION

Patients with low sTILs had a significantly poorer survival, despite adequate treatment with adjuvant therapy.

Combination of oxymatrine (Om) and astragaloside IV (As) enhances the infiltration and function of TILs in triple-negative breast cancer (TNBC)

Triple-negative breast cancer (TNBC) is the most aggressive subtype and has a poor response to treatment due to an immunosuppressive microenvironment. Chinese Medicine effective constituents such as oxymatrine (Om) and astragaloside IV (As) have shown promise in cancer treatment by providing anti-fibrosis and immune-enhancing effects. However, the potential combined effect of Om and As on TNBC and its mechanism is still uncertain. This study focuses on exploring the impact of Om and As on enhancing the immunosuppressive microenvironment of TNBC and uncovering the potential mechanism behind it. In this study, a trans-Cancer associated fibroblasts (CAFs) infiltration system of T cells was utilized to investigate the potential benefits of Om, while the impact of As on the morphology and quantity of mitochondria in T cells was examined in a co-culture system with tumor cells. Further to investigate the combined effects of Om and As on tumor suppression and immunosuppressive microenvironment improvement, this study established an in situ TNBC mouse model with 4 T1-luc. In vitro, our findings indicate that Om can effectively suppress the activation of CAFs by downregulating the expression of FAP and α-SMA, and also promoting the infiltration of T cells trans CAFs. It was discovered that the mitochondrial activity of T cells could be improved by increasing the number of mitochondria and cristae. In vivo, the optimal ratio of Om and As (2:1) was found to increase the apoptosis rate of tumor cells in a co-culture system and enhance the infiltration of CD4+ and CD8+ T cells, as confirmed by Flow Cytometry results. Our study suggests that Om and As could enhance the immune system's ability to treat TNBC by improving the infiltration and increasing the anti-tumor function of TILs. This intervention may lead to a promising therapeutic direction for the treatment of TNBC.

Inhibitory checkpoint molecule mRNA expression in canine soft tissue sarcoma

Canine soft tissue sarcomas (STS) are common neoplasms and considered immune deserts. Tumour infiltrating lymphocytes are sparse in STS and, when present, tend to organize around blood vessels or at the periphery of the neoplasm. This pattern is associated with an immunosuppressive tumour microenvironment linked to overexpression of molecules of the PD-axis. PD-1, PD-L1 and PD-L2 expression correlates with malignancy and poor prognosis in other neoplasms in humans and dogs, but little is known about their role in canine STS, their relationship to tumour grade, and how different therapies affect expression. The objective of this study was to evaluate the expression of checkpoint molecules across STS tumour grades and after tumour ablation treatment. Gene expression analysis was performed by reverse-transcriptase real-time quantitative PCR in soft tissue sarcomas that underwent histotripsy and from histologic specimens of STS from the Virginia Tech Animal Laboratory Services archives. The expression of PD-1, PD-L1 and PD-L2 was detected in untreated STS tissue representing grades 1, 2, and 3. Numerically decreased expression of all markers was observed in tissue sampled from the treatment interface relative to untreated areas of the tumour. The relatively lower expression of these checkpoint molecules at the periphery of the treated area may be related to liquefactive necrosis induced by the histotripsy treatment, and would potentially allow TILs to infiltrate the tumour. Relative increases of these checkpoint molecules in tumours of a higher grade and alongside immune cell infiltration are consistent with previous reports that associate their expression with malignancy.

Novel combinatorial therapy of oncolytic adenovirus AdV5/3-D24-ICOSL-CD40L with anti PD-1 exhibits enhanced anti-cancer efficacy through promotion of intratumoral T-cell infiltration and modulation of tumour microenvironment in mesothelioma mouse model

Introduction

Malignant mesothelioma is a rare and aggressive form of cancer. Despite improvements in cancer treatment, there are still no curative treatment modalities for advanced stage of the malignancy. The aim of this study was to evaluate the anti-tumor efficacy of a novel combinatorial therapy combining AdV5/3-D24-ICOSL-CD40L, an oncolytic vector, with an anti-PD-1 monoclonal antibody.

Methods

The efficacy of the vector was confirmed in vitro in three mesothelioma cell lines - H226, Mero-82, and MSTO-211H, and subsequently the antineoplastic properties in combination with anti-PD-1 was evaluated in xenograft H226 mesothelioma BALB/c and humanized NSG mouse models.

Results and discussion

Anticancer efficacy was attributed to reduced tumour volume and increased infiltration of tumour infiltrating lymphocytes, including activated cytotoxic T-cells (GrB+CD8+). Additionally, a correlation between tumour volume and activated CD8+ tumour infiltrating lymphocytes was observed. These findings were confirmed by transcriptomic analysis carried out on resected human tumour tissue, which also revealed upregulation of CD83 and CRTAM, as well as several chemokines (CXCL3, CXCL9, CXCL11) in the tumour microenvironment. Furthermore, according to observations, the combinatorial therapy had the strongest effect on reducing mesothelin and MUC16 levels. Gene set enrichment analysis suggested that the combinatorial therapy induced changes to the expression of genes belonging to the "adaptive immune response" gene ontology category. Combinatorial therapy with oncolytic adenovirus with checkpoint inhibitors may improve anticancer efficacy and survival by targeted cancer cell destruction and triggering of immunogenic cell death. Obtained results support further assessment of the AdV5/3-D24-ICOSL-CD40L in combination with checkpoint inhibitors as a novel therapeutic perspective for mesothelioma treatment.

One-step shotgun approach for antigenic specific pMHCs capture stimulated CD8+ T cell activation and proliferation

Antigenic peptides play a central role in immune surveillance in cancer, infectious disease, autoimmunity, and allergy. The identification and isolation of antigenic peptides for T cell immune response are crucial for successful personalized adoptive immune cell therapy. The mainly methods includes gene sequencing and bioinformatic analysis. The antigenic peptides which identified by analysis and artificially synthesized still need antigen presenting cell (APC) to deliver to T cells. However, high costs and lengthy process times have limited its application in clinical practice. In order to overcome it, this study attempted to directly capture antigenic peptide-major histocompatibility complex (MHC) class I (pMHCs) from cell lysates using streptavidin Dynabeads and biotin-labeled antibodies, then the pMHCs was co-cultured with tumor infiltrating lymphocytes (TILs) of the same tissue origin. The results indicated that the captured pMHCs were able to enrich the tumor antigen-specific CD8+ T cells, and also effectively induce proliferation and cytotoxic responses of CD8+ T cells. This study provided a novel approach for obtaining tumor antigenic pMHCs, which could enrich antigen-specific CD8+ T cells, and could also function as artificial APCs (aAPCs) to stimulate proliferation and activation of T cells. Notably, these pMHCs can stimulate the proliferation of stem-like memory T cells. In conclusion, this study describes a time-saving and low-cost method to isolate tumour antigen peptide MHC complexs, helping tumor antigen-specific T cell enrichment, activation, and proliferation.

Comparison of SP142 and 22C3 PD-L1 assays in a population-based cohort of triple-negative breast cancer patients in the context of their clinically established scoring algorithms

BACKGROUND

Immunohistochemical (IHC) PD-L1 expression is commonly employed as predictive biomarker for checkpoint inhibitors in triple-negative breast cancer (TNBC). However, IHC evaluation methods are non-uniform and further studies are needed to optimize clinical utility.

METHODS

We compared the concordance, prognostic value and gene expression between PD-L1 IHC expression by SP142 immune cell (IC) score and 22C3 combined positive score (CPS; companion IHC diagnostic assays for atezolizumab and pembrolizumab, respectively) in a population-based cohort of 232 early-stage TNBC patients.

RESULTS

The expression rates of PD-L1 for SP142 IC ≥ 1%, 22C3 CPS ≥ 10, 22C3 CPS ≥ 1 and 22C3 IC ≥ 1% were 50.9%, 27.2%, 53.9% and 41.8%, respectively. The analytical concordance (kappa values) between SP142 IC+ and these three different 22C3 scorings were 73.7% (0.48, weak agreement), 81.5% (0.63) and 86.6% (0.73), respectively. The SP142 assay was better at identifying 22C3 positive tumors than the 22C3 assay was at detecting SP142 positive tumors. PD-L1 (CD274) gene expression (mRNA) showed a strong positive association with all two-categorical IHC scorings of the PD-L1 expression, irrespective of antibody and cut-off (Spearman Rho ranged from 0.59 to 0.62; all p-values < 0.001). PD-L1 IHC positivity and abundance of tumor infiltrating lymphocytes were of positive prognostic value in univariable regression analyses in patients treated with (neo)adjuvant chemotherapy, where it was strongest for 22C3 CPS ≥ 10 and distant relapse-free interval (HR = 0.18, p = 0.019). However, PD-L1 status was not independently prognostic when adjusting for abundance of tumor infiltrating lymphocytes in multivariable analyses.

CONCLUSION

Our findings support that the SP142 and 22C3 IHC assays, with their respective clinically applied scoring algorithms, are not analytically equivalent where they identify partially non-overlapping subpopulations of TNBC patients and cannot be substituted with one another regarding PD-L1 detection. Trial registration The Swedish Cancerome Analysis Network - Breast (SCAN-B) study, retrospectively registered 2nd Dec 2014 at ClinicalTrials.gov; ID NCT02306096.

Increased expression of IDO1 is associated with improved survival and increased number of TILs in patients with high-grade serous ovarian cancer

BACKGROUND

The enzyme indoleamine 2,3-dioxygenase 1 (IDO1) plays a crucial role in regulating the immune system's response to tumors, but its exact role in cancer, especially in high-grade serous ovarian cancer (HGSOC), remains controversial. We aimed to investigate the prognostic impact of IDO1 expression and its correlation with tumor-infiltrating lymphocytes (TILs) in HGSOC.

METHODS

Immunohistochemical (IHC) staining and bioimage analysis using the QuPath software were employed to assess IDO1 protein expression in a well-characterized cohort of 507 patients with primary HGSOC. Statistical evaluation was performed using SPSS, and in silico validation considering IDO1 mRNA expression in bulk and single-cell gene expression datasets was conducted. Additionally, IDO1 expression in interferon-gamma (IFNG) stimulated HGSOC cell lines was analyzed.

RESULTS

Our findings revealed that IDO1 protein and mRNA expression serve as positive prognostic markers for overall survival (OS) and progression-free survival (PFS) in HGSOC. High IDO1 expression was associated with a significant improvement in OS by 21 months (p < 0.001) and PFS by 6 months (p = 0.016). Notably, elevated IDO1 expression correlated with an increased number of CD3+ (p < 0.001), CD4+ (p < 0.001), and CD8+ TILs (p < 0.001). Furthermore, high IDO1 mRNA expression and protein level were found to be associated with enhanced responsiveness to pro-inflammatory cytokines, particularly IFNG.

CONCLUSIONS

Our study provides evidence that IDO1 expression serves as a positive prognostic marker in HGSOC and is associated with an increased number of CD3+, CD4+ and CD8+ TILs. Understanding the intricate relationship between IDO1, TILs, and the tumor microenvironment may hold the key to improving outcomes in HGSOC.

Prognostic Factors in Advanced Non-Small Cell Lung Cancer Patients Treated with Immunotherapy

Taking into account the huge epidemiologic impact of lung cancer (in 2020, lung cancer accounted for 2,206,771 of the cases and for 1,796,144 of the cancer-related deaths, representing the second most common cancer in female patients, the most common cancer in male patients, and the second most common cancer in male and female patients) and the current lack of recommendations in terms of prognostic factors for patients selection and management, this article aims to provide an overview of the current landscape in terms of currently available immunotherapy treatments and the most promising assessed prognostic biomarkers, highlighting the current state-of-the-art and hinting at future challenges.

Microscopical Variables and Tumor Inflammatory Microenvironment Do Not Modify Survival or Recurrence in Stage I-IIA Lung Adenocarcinomas

Microscopical predictors and Tumor Immune Microenvironment (TIME) have been studied less in early-stage NSCLC due to the curative intent of resection and the satisfactory survival rate achievable. Despite this, the emerging literature enforces the role of the immune system and microscopical predictors as prognostic variables in NSCLC and in adenocarcinomas (ADCs) as well. Here, we investigated whether cancer-related microscopical variables and TIME influence survival and recurrence in I-IIA ADCs. We retrospectively collected I-IIA ADCs treated (lobectomy or segmentectomy) at the University Hospital (Padova) between 2016 and 2022. We assigned to pathological variables a cumulative pathological score (PS) resulting as the sum of them. TIME was investigated as tumor-infiltrating lymphocytes (TILs < 11% or ≥11%) and PD-L1 considering its expression (<1% or ≥1%). Then, we compared survival and recurrence according to PS, histology, TILs and PD-L1. A total of 358 I-IIA ADCs met the inclusion criteria. The median PS grew from IA1 to IIA, indicating an increasing microscopical cancer activity. Except for the T-SUVmax, any pathological predictor seemed to be different between PD-L1 < 1% and ≥1%. Histology, PS, TILs and PD-L1 were unable to indicate a survival difference according to the Log-rank test (p = 0.37, p = 0.25, p = 0.41 and p = 0.23). Even the recurrence was non-significant (p = 0.90, p = 0.62, p = 0.97, p = 0.74). According to our findings, resection remains the best upfront treatment in I-IIA ADCs. Microscopical cancer activity grows from IA1 to IIA tumors, but it does not affect outcomes. These outcomes are also unmodified by TIME. Probably, microscopical cancer development and immune reaction against cancer are overwhelmed by an adequate R0-N0 resection.

Tumor Infiltrating Lymphocytes (TILS) and PD-L1 Expression in Breast Cancer: A Review of Current Evidence and Prognostic Implications from Pathologist's Perspective

With the rise of novel immunotherapies able to stimulate the antitumor immune response, increasing literature concerning the immunogenicity of breast cancer has 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 response in BC. TILs are more frequently observed in triple-negative breast cancer and HER2+ subtypes, where increased TIL levels have been linked to a better response to neoadjuvant chemotherapy and 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. Briefly, TNBC shows the highest percentage 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 of the current knowledge of the immune landscape of BC is provided. TILS and PD-L1 expression across different BC subtypes are discussed, providing a guide for their pathological assessment and reporting.

Tumor-Specific CD8+ T Cells from the Bone Marrow Resist Exhaustion and Exhibit Increased Persistence in Tumor-Bearing Hosts as Compared to Tumor Infiltrating Lymphocytes

Immunotherapy is now an integral aspect of cancer therapy. Strategies employing adoptive cell therapy (ACT) have seen the establishment of chimeric antigen receptor (CAR)-T cells using peripheral blood lymphocytes as well as tumor infiltrating lymphocytes (TILs) with significant clinical results. Despite these successes, the limitations of the current strategies are also emerging and novel approaches are needed. The bone marrow (BM) is an immunological niche that houses T cells with specificity for previously encountered antigens, including tumor-associated antigens from certain solid cancers. This study sought to improve our understanding of tumor-specific BM T cells in the context of solid tumors by comparing them with TILs, and to assess whether there is a rationale for using the BM as a source of T cells for ACT against solid malignancies. Herein, we demonstrate that T cells from the BM appear superior to TILs as a source of cells for cellular therapy. Specifically, they possess a memory-enriched phenotype and exhibit improved effector function, greater persistence within a tumor-bearing host, and the capacity for increased tumor infiltration. Taken together, these data provide a foundation for further exploring the BM as a source of tumor-specific T cells for ACT in solid malignancies.

Targeting of multiple tumor-associated antigens by individual T cell receptors during successful cancer immunotherapy

The T cells of the immune system can target tumors and clear solid cancers following tumor-infiltrating lymphocyte (TIL) therapy. We used combinatorial peptide libraries and a proteomic database to reveal the antigen specificities of persistent cancer-specific T cell receptors (TCRs) following successful TIL therapy for stage IV malignant melanoma. Remarkably, individual TCRs could target multiple different tumor types via the HLA A∗02:01-restricted epitopes EAAGIGILTV, LLLGIGILVL, and NLSALGIFST from Melan A, BST2, and IMP2, respectively. Atomic structures of a TCR bound to all three antigens revealed the importance of the shared x-x-x-A/G-I/L-G-I-x-x-x recognition motif. Multi-epitope targeting allows individual T cells to attack cancer in several ways simultaneously. Such "multipronged" T cells exhibited superior recognition of cancer cells compared with conventional T cell recognition of individual epitopes, making them attractive candidates for the development of future immunotherapies.

Cellular Therapy for Lung Cancer: Focusing on Chimeric Antigen Receptor T (CAR T) Cells and Tumor-Infiltrating Lymphocyte (TIL) Therapy

Lung cancer is a leading cause of morbidity and mortality in the United States and worldwide. The introduction of immune checkpoint inhibitors has led to a marked improvement in the outcomes of lung cancer patients. Despite these advances, there is a huge unmet need for therapeutic options in patients who are not candidates for targeted or immunotherapy or those who progress after first-line treatment. With its high mutational burden, lung cancer appears to be an attractive target for novel personalized treatment approaches. In this review, we provide an overview of two adoptive cell therapy approaches-chimeric antigen receptors (CAR) T-cell therapy and Tumor-infiltrating lymphocytes (TILs) in lung cancer with an emphasis on current challenges and future perspectives. While both these therapies are still in the early phases of development in lung cancer and need more refinement, they harbor the potential to be effective treatment options for this group of patients with otherwise poor prognoses.

Expression of Programmed Death Ligand1 (PD-L1) in Gastric Carcinoma (Histopathological and Immunohistochemical Study)

OBJECTIVES

To evaluate immunohistochemical expression of PD-L1 in cases of gastric adenocarcinoma. To correlate PD-L1 immuno-histochemical expression with other available clinico-pathological parameters such as age, sex, grade, stage, lymph node (L.N) metastasis and others.

MATERIAL AND METHODS

The present retrospective study retrieved the data and archived paraffin blocks of 60 cases of Gastric carcinoma. Immunohistochemical evaluation was done to assess the expressions of PD-L1 in the tumor cells (TC), tumor infiltrated lymphocytes (TILs) and combined positive score (CPS).

RESULTS

TC PD-L1 expression was detected in 56.7% of cases, TILs PD-L1 expression was detected in 53.3 % of cases and CPS PD-L1 expression was detected in 63.3% of case, with no statistically significant correlation with clinico-pathological parameters except TILs PD-L1 expression showed statistically significant correlation with positive TILs (P value ˂0.019).

CONCLUSION

Our findings supported the expression of PD-L1 by TC, TILs, and CPS in gastric cancer, with increased expression in a subpopulation of TILs rich in PD-L1 identifying them as potential targets for PD-1/PD-L1 therapy.

89Zr-immuno-PET using the anti-LAG-3 tracer [89Zr]Zr-BI 754111: demonstrating target specific binding in NSCLC and HNSCC

PURPOSE

Although lymphocyte activation gene-3 (LAG-3) directed therapies demonstrate promising clinical anti-cancer activity, only a subset of patients seems to benefit and predictive biomarkers are lacking. Here, we explored the potential use of the anti-LAG-3 antibody tracer [89Zr]Zr-BI 754111 as a predictive imaging biomarker and investigated its target specific uptake as well as the correlation of its tumor uptake and the tumor immune infiltration.

METHODS

Patients with head and neck (N = 2) or lung cancer (N = 4) were included in an imaging substudy of a phase 1 trial with BI 754091 (anti-PD-1) and BI 754111 (anti-LAG-3). After baseline tumor biopsy and [18F]FDG-PET, patients were given 240 mg of BI 754091, followed 8 days later by administration of [89Zr]Zr-BI 754111 (37 MBq, 4 mg). PET scans were performed 2 h, 96 h, and 144 h post-injection. To investigate target specificity, a second tracer administration was given two weeks later, this time with pre-administration of 40 (N = 3) or 600 mg (N = 3) unlabeled BI 754111, followed by PET scans at 96 h and 144 h post-injection. Tumor immune cell infiltration was assessed by immunohistochemistry and RNA sequencing.

RESULTS

Tracer uptake in tumors was clearly visible at the 4-mg mass dose (tumor-to-plasma ratio 1.63 [IQR 0.37-2.89]) and could be saturated by increasing mass doses (44 mg: 0.67 [IQR 0.50-0.85]; 604 mg: 0.56 [IQR 0.42-0.75]), demonstrating target specificity. Tumor uptake correlated to immune cell-derived RNA signatures.

CONCLUSIONS

[89Zr]Zr-BI-754111 PET imaging shows favorable technical and biological characteristics for developing a potential predictive imaging biomarker for LAG-3-directed therapies.

TRIAL REGISTRATION

ClinicalTrials.gov , NCT03780725. Registered 19 December 2018.

T cell immunotherapy for cervical cancer: challenges and opportunities

Cancer cellular immunotherapy has made inspiring therapeutic effects in clinical practices, which brings new hope for the cure of cervical cancer. CD8+T cells are the effective cytotoxic effector cells against cancer in antitumor immunity, and T cells-based immunotherapy plays a crucial role in cellular immunotherapy. Tumor infiltrated Lymphocytes (TIL), the natural T cells, is approved for cervical cancer immunotherapy, and Engineered T cells therapy also has impressive progress. T cells with natural or engineered tumor antigen binding sites (CAR-T, TCR-T) are expanded in vitro, and re-infused back into the patients to eradicate tumor cells. This review summarizes the preclinical research and clinical applications of T cell-based immunotherapy for cervical cancer, and the challenges for cervical cancer immunotherapy.

Immunotherapy for Metastatic Triple Negative Breast Cancer: Current Paradigm and Future Approaches

OPINION STATEMENT

In approximately 15-20% of the patients diagnosed with breast cancer, it comprises the triple negative (TN) subtype, which until recently lacked targets for specific treatments and is known for its aggressive clinical behavior in patients with metastatic disease. TNBC is considered the most immunogenic breast cancer subtype due to higher levels of tumor infiltrating lymphocytes (TILs), tumor mutational burden and PD-L1 expression, providing a rationale for immunotherapy. The addition of pembrolizumab to chemotherapy as first-line treatment resulted in significantly improved PFS and OS for PD-L1 positive mTNBC, leading to FDA approval. However, response rate of ICB in unselected patients is low. Ongoing (pre)clinical trials aim to further optimize ICB efficacy and widen its application beyond PD-L1 positive breast tumors. Novel immunomodulatory approaches to induce a more inflamed tumor microenvironment include dual checkpoint blockade, bispecific antibodies, immunocytokines, adoptive cell therapies, oncolytic viruses, and cancer vaccines. Preclinical data for these novel strategies seems promising, but solid clinical data to further support its application for mTNBC is awaited. Biomarkers capturing the degree of immunogenicity such as but not limited to TILs, CD8 T cell levels, and IFNg signatures could support deciding which therapeutic strategy is most appropriate for which patient. Given 1) the accumulating therapy options for patients with metastatic disease and 2) the heterogeneity of mTNBC from inflamed to immune-desert tumors, the challenge is to work towards immunomodulatory strategies for specific subgroups of patients with TNBC to enable personalized (immuno)therapy for patients with metastatic disease.

Status and prognostic value of immunological biomarkers of breast cancer

The immune response to cancer serves an important role in disease progression and patient prognosis. For triple-negative breast cancer showing aggressive behavior, immunotherapy has a good efficacy because of the potent immunogenicity of this type of cancer. However, the dominant subtype, luminal human epidermal growth factor receptor-2 (HER2)-negative breast cancer, is less immunogenic. To determine whether luminal HER2-negative cancer reacts to the anticancer immune response, the present study analyzed the status and prognostic value of the principal immunological biomarkers of breast cancer, including tumor-infiltrating lymphocytes (TILs), CD8⁺ T lymphocytes, the major histocompatibility complex and programmed cell death ligand-1 (PD-L1). The biomarkers were compared between patients with luminal HER2-negative breast cancer and those with immunogenic subtypes including triple-negative and HER2-overexpressed breast cancer. A total of 71 patients with primary breast cancer were classified into the immunogenic non-luminal (n=23) and less immunogenic luminal HER2-negative groups (n=48) based on immunogenicity. In the luminal HER2-negative group, compared with patients with low TIL levels, those with high TIL levels were at an advanced stage of cancer (P=0.024) and showed worse relapse-free survival (P=0.057); however, the remaining biomarkers exhibited no association with cancer progression or prognosis. In the non-luminal group, patients with high TIL levels showed significantly better RFS than those with low TIL levels (P=0.014). Compared with non-luminal patients negative for PD-L1, those positive for PD-L1 exhibited better overall survival (P=0.064). Notably, TIL status was found to exhibit contrasting prognostic predictions based on immunogenicity. In conclusion, TILs are a strong candidate for prognostic prediction in breast cancer, regardless of the subtype. PD-L1 is a potential candidate for prognostic prediction in immunogenic breast cancers, but not in the luminal HER2-negative subtype.

Expression of programmed death ligand-1 (PD-L1) and tumor infiltrating lymphocytes (TILs) in breast carcinoma and their clinical significance

Background and Aim

Carcinoma of the breast is the second most common cause of cancer death in women. Expression of programmed death ligand-1 (PD-L1) in cancer cells plays an important role in tailored therapy. This can be evaluated by immunohistochemistry using a monoclonal PD-L1 antibody in formalin-fixed and paraffin-embedded (FFPE) specimens. Our aim was to evaluate the expression of PD-L1 and tumor infiltrating lymphocytes (TILs) in invasive carcinoma of breast and their clinicopathological correlation.

Materials and Methods

Immunohistochemical staining for PD-L1 and TILs was done in paraffin-embedded tissues of histologically diagnosed 50 cases of breast carcinoma. Statistical analysis was done using Statistical Package for the Social Sciences (SPSS) 22 software.

Results

Out of these 50 cases, PD-L1 and TIL expression were seen in 16 (32%) cases and 18 (36%) cases, respectively. PD-L1 positivity was seen in 33.33% cases of grade 1 breast carcinoma, 13.79% of cases of grade 2 breast carcinoma, and in 75% case of grade 3 breast carcinoma. TILs showed positivity in 6.9% cases of grade 1 breast carcinoma, 13.79% of cases of grade 2 breast carcinoma, and in 100% cases of grade 3 breast carcinoma. Proportion of patients having PD-L1 expression was higher in grade 3 carcinoma than in grade 1 or 2. The differences were statistically significant (Chi-square value = 13.417, degree of freedom = 1, P < 0.05). The Chi-square value for TILs was 28.07, degree of freedom was 1, and P value was <0.05, which was statistically significant.

Conclusion

Both PD-L1 and TILs showed maximum positivity in grade 3 breast carcinoma.

Tumor immune microenvironment alterations using induction cetuximab in a phase II trial of deintensified therapy for p16-positive oropharynx cancer

BACKGROUND

We sought to characterize early changes in CD8⁺ tumor-infiltrating lymphocytes and tumor transcriptomes after induction cetuximab in a cohort with p16-positive oropharyngeal cancer on a phase II clinical de-escalation trial.

METHODS

Tumor biopsies were obtained before and 1 week after a single cetuximab loading dose in eight patients enrolled in a phase II trial of cetuximab and radiotherapy. Changes in CD8⁺ tumor-infiltrating lymphocytes and transcriptomes were assessed.

RESULTS

One week after cetuximab, five patients (62.5%) had an increase in CD8⁺ cell infiltration with a median (range) fold change of +5.8 (2.5-15.8). Three (37.5%) had unchanged CD8⁺ cells (median [range] fold change of -0.85 [0.8-1.1]). In two patients with evaluable RNA, cetuximab induced rapid tumor transcriptome changes in cellular type 1 interferon signaling and keratinization pathways.

CONCLUSIONS

Within 1 week, cetuximab induced measurable changes in pro-cytotoxic T-cell signaling and immune content.

Frequency of Her2-low in colorectal cancer and its relations with the tumor microenvironment

BACKGROUND

To date, little is known regarding human epithelial growth factor receptor (HER2) low-expressing colorectal cancer (CRC). Due to promising rising therapies with HER2-antibody-drug conjugates we aimed to analyze the frequency of HER2-low in patients with CRC. Additionally we characterized the clinicopathologic background of this group and its potential relationship with the tumor microenvironment represented by budding and tumor infiltrating lymphocytes (TILs).

METHODS

319 patients with CRC, stages I-IV, were enrolled. HER2-immunohistochemistry (IHC) as well as fluorescence in situ hybridization (FISH) were performed on tissue microarrays. IHC was evaluated semiquantitatively and software-assisted using the HERACLES Diagnostic Criteria for CRC. HER2-low was defined as IHC 1 + or 2 +/FISH negative. HER2-IHC results were compared with budding, TILs and their combinations.

RESULTS

The HER2 low-expressing subset represented almost one half of all CRC (47.1 %). Assessment was highly reproducible with different methods. HER2-low cases were significantly more often lower T-, N-, and tumor stage and had less L1 compared with HER2-0. Additionally, they showed more often TILs > 5 % (p = 0.001). The difference between HER2-0 and HER2-low was highly significant between the four budding/TILs-groups (p < 0.001). Cases with low budding/high TILs were more often HER2-low. The highest difference was seen between the low budding/high TILs-group and the low budding/low TILs-group (p < 0.001).

CONCLUSIONS

HER2-low expression in CRC is frequent and involves nearly one half of all patients. We could show a relationsship between HER2-low expression and the tumor microenvironment. Special attention should be paid to the low budding/high TILs group in future research.

Programmed death ligand 1-positive immune cells in primary tumor or metastatic axillary lymph nodes can predict prognosis of triple-negative breast cancer even when present at < 1% in the tumor region

BACKGROUND

The efficacy of pre-operative systemic treatment (PST) combined with immune checkpoint inhibition (ICI) for triple-negative breast cancer (TNBC) has been recognized recently as being independent of the degree of programmed death ligand-1 (PD-L1) positivity of infiltrating immune cells, especially for patients with axillary lymph node metastasis (ALNM).

METHODS

TNBC patients with ALNM were treated surgically between 2002 and 2016 in our facility (n = 109), of whom 38 received PST before resection. The presence of tumor-infiltrating lymphocytes (TILs) expressing CD3, CD8, CD68, PD-L1 (detected by antibody SP142) and FOXP3 at primary and metastatic LN sites was quantified.

RESULTS

The size of invasive tumor and the number of metastatic axillary LN were confirmed as prognostic markers. The numbers of both CD8+ and FOXP3+ TILs at primary sites were also recognized as prognostic markers, especially for overall survival (OS) (CD8, p = 0.026; FOXP3, p < 0.001). The presence of CD8+, FOXP3+ and PD-L1+ cells was better maintained in LN after PST and may contribute to improved antitumor immunity. Provided they were present as clusters of ≥ 70 positive cells, even < 1% of immune cells expressing PD-L1 at primary sites predicted a more favorable prognosis for both disease-free survival (DFS) (p = 0.004) and OS (p = 0.020). This was the case not only for 30 matched surgical patients, but also in all 71 surgical only patients (DFS: p < 0.001 and OS: p = 0.002).

CONCLUSIONS

PD-L1+ , CD8+ or FOXP3+ immune cells in the tumor microenvironment (TME) at both primary and metastatic sites are significant on prognosis, which could be a clue to expect the potential for better responses to the combination of chemotherapy and ICI, especially for patients with ALNM.

Joint detection of multiple HPV-testing technologies and evaluation of clinicopathological characteristics discriminate between HPV-independent and low-copy HPV-associated cervical squamous cell carcinoma (CSCC) -an analysis of 3869 cases

OBJECTIVES

This study aimed to investigate the frequency and clinicopathological characteristics of HPV-independent cervical squamous cell carcinoma (CSCC).

METHODS

A total of 3869 patients with CSCC from 2017 to 2021 were searched. p16^INK4a immunochemistry (IHC), two HPV-DNA(L1) polymerase chain reactions and HPV mRNA in situ hybridization were performed. Viral copies were detected using the 21 HPV quantitative test.

RESULTS

Six cases showed negative results in all four assays (group 1, 0.16%). Twenty-seven cases showed discordant results (group 2), and 3836 cases presented all-positive results (group 3). p16^INK4a IHC showed similar sensitivity, specificity, and positive predictive value compared to the other three direct HPV assays. 21 HPV genotyping showed 100% of negative predictive value. HPV copies were extremely lower in Group 2 than in Group 3 (P < 0.01), but were not significantly different from those in Group 1. Older age, advanced FIGO stage (III-IV) and abnormal p53 (p53abn) IHC were independent predictors of HPV-negative status in univariate and multivariate logistic regression. Group 2 had similar proportions of age >60 years and p53abn IHC with Group 1, but had fewer cases with advanced FIGO stage (P < 0.05) and TILs (P < 0.05). Groups 1 and 2 had worse disease-free survival (DFS) and disease-specific survival (DSS) than Group 3 (P < 0.01), while no significant difference was found between these two groups. HPV-negative status was a risk factor for both DFS (P < 0.05) and DSS (P < 0.01) in univariate but not multivariate Cox regression.

CONCLUSIONS

Joint detection of multiple technologies and evaluation of clinicopathological characteristics discriminate between HPV-independent and low-copy HPV-associated CSCC cases that present similar prognoses. Additional attention should be paid to these low-copy HPV-associated cases in clinical practice.

Regression in cutaneous melanoma: histological assessment, immune mechanisms and clinical implications

Tumour regression is an immunologically driven process that results in complete or partial disappearance of tumour cells. This can be observed in histological sections as replacement of tumour cells with fibrosis, angiogenesis, and a variable inflammatory infiltrate. In primary cutaneous melanoma, the prognostic significance of regression has been debated for decades, in part because inconsistent histological criteria are used in prognostication studies. It is broadly accepted that CD8+ T lymphocytes are the primary effectors of the anti-tumour response, but the interplay between melanoma and the immune system is complex, dynamic, and incompletely understood. Sustained progress in unravelling the pathogenesis of melanoma regression has led to the identification of therapeutic targets, culminating in the development of immune checkpoint inhibitors for the management of advanced disease. Modern techniques allow for high-resolution spatial analyses of the tumour microenvironment. Such studies may lead to better understanding of the immune drivers of melanoma regression, thereby facilitating the search for new prognostic and predictive biomarkers to assist clinical decision-making.

The Prognostic Impact of Gender, Therapeutic Strategies, Molecular Background, and Tumor-Infiltrating Lymphocytes in Glioblastoma: A Still Unsolved Jigsaw

Despite the adoption of novel therapeutical approaches, the outcomes for glioblastoma (GBM) patients remain poor. In the present study, we investigated the prognostic impact of several clinico-pathological and molecular features as well as the role of the cellular immune response in a series of 59 GBM. CD4+ and CD8+ tumor-infiltrating lymphocytes (TILs) were digitally assessed on tissue microarray cores and their prognostic role was investigated. Moreover, the impact of other clinico-pathological features was evaluated. The number of CD4+ and CD8+ is higher in GBM tissue compared to normal brain tissue (p < 0.0001 and p = 0.0005 respectively). A positive correlation between CD4+ and CD8+ in GBM is present (rs = 0.417-p = 0.001). CD4+ TILs are inversely related to overall survival (OS) (HR = 1.79, 95% CI 1.1-3.1, p = 0.035). The presence of low CD4+ TILs combined with low CD8+ TILs is an independent predictor of longer OS (HR 0.38, 95% CI 0.18-0.79, p = 0.014). Female sex is independently related to longer OS (HR 0.42, 95% CI 0.22-0.77, p = 0.006). Adjuvant treatment, methylguanine methyltransferase (MGMT) promoter methylation, and age remain important prognostic factors but are influenced by other features. Adaptive cell-mediated immunity can affect the outcomes of GBM patients. Further studies are needed to elucidate the commitment of the CD4+ cells and the effects of different TILs subpopulations in GBM.

ONEST (Observers Needed to Evaluate Subjective Tests) Analysis of Stromal Tumour-Infiltrating Lymphocytes (sTILs) in Breast Cancer and Its Limitations

Tumour-infiltrating lymphocytes (TILs) reflect antitumour immunity. Their evaluation of histopathology specimens is influenced by several factors and is subject to issues of reproducibility. ONEST (Observers Needed to Evaluate Subjective Tests) helps in determining the number of observers that would be sufficient for the reliable estimation of inter-observer agreement of TIL categorisation. This has not been explored previously in relation to TILs. ONEST analyses, using an open-source software developed by the first author, were performed on TIL quantification in breast cancers taken from two previous studies. These were one reproducibility study involving 49 breast cancers, 23 in the first circulation and 14 pathologists in the second circulation, and one study involving 100 cases and 9 pathologists. In addition to the estimates of the number of observers required, other factors influencing the results of ONEST were examined. The analyses reveal that between six and nine observers (range 2-11) are most commonly needed to give a robust estimate of reproducibility. In addition, the number and experience of observers, the distribution of values around or away from the extremes, and outliers in the classification also influence the results. Due to the simplicity and the potentially relevant information it may give, we propose ONEST to be a part of new reproducibility analyses.

The Genetic and Immunologic Landscape Underlying the Risk of Malignant Progression in Laryngeal Dysplasia

(1) Background: The development of laryngeal cancer is a multistep process involving structural alterations of the epithelial mucosa, from dysplasia (LDy) to invasive carcinoma. In this study, we define new biomarkers, prognostic for malignant transformation, in patients affected by LDy. (2) Methods: We used targeted next-generation sequencing and immunohistochemical analysis to define the mutational and immunological landscape of 15 laryngeal dysplasia progressing to invasive cancer (progressing dysplasia), as well as 31 cases of laryngeal dysplasia that did not progress to carcinoma (non-progressing dysplasia). Two pathologists independently analyzed the presence of tumor-infiltrating lymphocytes in LDy pre-embedded paraffin-fixed specimens. The RNA-based next-generation sequencing panel OIRRA was used to evaluate the expression of 395 genes related to immune system activation. (3) Results: High TILs are significantly correlated with a higher risk of malignant transformation. The non-brisk pattern was significantly associated with an 86% reduced risk of malignant progression (OR = 0.16, 95% CI: 0.03-0.5, p = 0.008). TILs showed a highly positive correlation with CCR6, CD83, HLA-DPB1, MX1 and SNAI1, and they were inversely correlated with CD48, CIITA, CXCR4, FCER1G, IL1B, LST1 and TLR8. (4) Conclusions: TILs have a great potential to identify high-risk progression dysplasia and thus to define surveillance protocols and prevention programs.

Triple-Negative Breast Cancer and Predictive Markers of Response to Neoadjuvant Chemotherapy: A Systematic Review

Around 40-50% of all triple-negative breast cancer (TNBC) patients achieve a pathological complete response (pCR) after treatment with neoadjuvant chemotherapy (NAC). The identification of biomarkers predicting the response to NAC could be helpful for personalized treatment. This systematic review provides an overview of putative biomarkers at baseline that are predictive for a pCR following NAC. Embase, Medline and Web of Science were searched for articles published between January 2010 and August 2022. The articles had to meet the following criteria: patients with primary invasive TNBC without distant metastases and patients must have received NAC. In total, 2045 articles were screened by two reviewers resulting in the inclusion of 92 articles. Overall, the most frequently reported biomarkers associated with a pCR were a high expression of Ki-67, an expression of PD-L1 and the abundance of tumor-infiltrating lymphocytes, particularly CD8+ T cells, and corresponding immune gene signatures. In addition, our review reveals proteomic, genomic and transcriptomic markers that relate to cancer cells, the tumor microenvironment and the peripheral blood, which also affect chemo-sensitivity. We conclude that a prediction model based on a combination of tumor and immune markers is likely to better stratify TNBC patients with respect to NAC response.

Systemic immune mediators reflect tumour-infiltrating lymphocyte intensity and predict therapeutic response in triple-negative breast cancer

Triple-negative breast cancer (TNBC) is an aggressive form of breast cancer (BC). Neoadjuvant chemotherapy has proven efficacy in its treatment, and a pathological complete response (pCR) to therapy is predictive of improved long-term survival. The immune response is key to successful neoadjuvant chemotherapy, as indicated by the relation between the percentage of stromal tumour-infiltrating lymphocytes (TILs) in pre-treated tumour tissue samples and the likelihood of achieving pCR. Here we studied systemic immune mediators from volunteer TNBC patients before undergoing neoadjuvant chemotherapy to determine the systemic response association with TIL intensity, treatment response and survival. Patients were classified into pCR responder or non-responder at time of surgery. We found higher levels of immune mediators before treatment began in patients that went on to be pCR responders versus non-pCR, with area under the curve (AUC) values of 0.64-0.80. We also observed a positive correlation between inflammatory systemic immune mediators and the percentage of TILs in pCR responder patients. Combining TILs and systemic immune mediator levels provided stronger AUC values (range of 0.72-0.82). Last, performing a progression-free survival analysis with several of the systemic cytokines that predict pCR, segregated the patients into long- and short-survival groups based on high and low production of the cytokines, respectively. Our study demonstrates that circulating cytokines, before treatment begins, predict pCR in TNBC patients treated with neoadjuvant chemotherapy. Moreover, they may act as a surrogate marker of high TILs or together with TILs to better predict pCR and survival.

Modification of Breast Cancer Milieu with Chemotherapy plus Dendritic Cell Vaccine: An Approach to Select Best Therapeutic Strategies

BACKGROUND

The addition of dendritic cell vaccines (DCV) to NAC could induce immune responses in those patients with residual disease (RD) by transforming the tumor microenvironment.

METHODS

Core diagnostic biopsies and surgical specimens from 80 patients (38 in the vaccinated group plus NAC (VG) and 42 in the control group (CG, treated only with NAC) were selected. We quantify TILs (CD8, CD4 and CD45RO) using immunohistochemistry and the automated cellular imaging system (ACIS III) in paired samples.

RESULTS

A CD8 rise in TNBC samples was observed after NAC plus DCV, changing from 4.48% in the biopsy to 6.70% in the surgical specimen, not reaching statistically significant differences (p = 0.11). This enrichment was seen in up to 67% of TNBC patients in the experimental arm as compared with the CG (20%). An association between CD8 TILs before NAC (4% cut-off point) and pathological complete response in the VG was found in the univariate and multivariate analysis (OR = 1.41, IC95% 1.05-1.90; p = 0.02, and OR = 2.0, IC95% 1.05-3.9; p = 0.03, respectively).

CONCLUSION

Our findings suggest that patients with TNBC could benefit from the stimulation of the antitumor immune system by using DCV together with NAC.