Intratumoral Expression Research Articles

The prognostic value of the tumor-stroma ratio compared to tumor-infiltrating lymphocytes in triple-negative breast cancer: a review.

Previous literature extensively explored biomarkers to personalize treatment for breast cancer patients. The clinical need is especially high in patients with triple-negative breast cancer (TNBC) due to its aggressive nature and limited treatment modalities. This review aims to evaluate the value of tumor-infiltrating lymphocytes (TILs) and tumor-stroma ratio (TSR) as prognostic biomarkers in TNBC patients and assess their clinical potential. A literature search was conducted in PubMed, Embase, Emcare, Web of Science, and Cochrane Library. Papers comparing survival outcomes of TNBC patients with low/high or negative/positive TSR and immune cells were included. The most frequently mentioned subgroups of TILs were selected and reported in this review. Data from 43 articles on TILs and eight articles on TSR were included. Among TNBC patients, high CD8 expression was generally associated with better survival. Notable, the poor survival outcomes were related to high intra-tumoral PD-L1 expression, whereas high stromal PD-L1 expression more often was correlated with favorable outcomes. For the TSR, a high amount of stroma in the primary tumor of TNBC patients was consistently associated with worse survival. This review highlights that a high number of CD8-positive T-cells is a promising prognostic factor for TNBC patients. PD-L1 expression analyzed for intra-tumoral and stromal expression separately reports strong but contrasting information. Finally, the TSR shows potential to be an important prognostic marker, especially for TNBC patients. Utilizing both biomarkers, either on itself or combined, could enhance clinical decision-making and personalization of treatment.

ERα, HER-2, pan-RAS, p53, and aromatase expression in spontaneous malignant canine mammary tumors: Prognostic relevance and association with clinicohistological parameters.

The interlacing interaction between proto-oncoproteins and tumor-suppressing proteins in malignant canine mammary tumors (mCMT) microenvironment remains largely unexplored. The present study intended to decipher the i) association between the intratumoral expression of ERα, HER-2, pan-RAS, p53 and aromatase, ii) their relationship with the clinicohistological parameters and serum sex hormones, and iii) their prognostic relevance in mCMT. Tumor samples from animals with mCMT (n=27) were subjected to histopathology and immunohistochemistry for ERα, HER-2, pan-RAS, p53, and aromatase. Serum estradiol and progesterone levels from dogs with mCMT and healthy dogs (n=10) were estimated using chemiluminescence immunoassay. Kaplan-Meier analysis (log-rank test), univariable and multivariable Cox regression, and Mann-Whitney U test were employed for statistical analysis. The expression of aromatase, ERα, pan-RAS, p53, and HER-2 were detected in 100%, 88%, 67%, 12% and 11% of mCMT cases, respectively. Serum estradiol and progesterone were significantly higher in mCMT-affiliated patients than healthy dogs. Also, a positive association of ERα expression with aromatase (stromal component) and HER2 expression in mCMT patients was detected. Furthermore, intratumoral aromatase expression and p53 overexpression were correlated with tumor size and angiogenesis, respectively. No relationship was detected between other tumor markers, serum steroid hormones and clinicohistological parameters. P53 overexpression was associated with poor survival in mCMT patients. Overexpression of aromatase and p53 overexpression has clinical relevance in mCMT, and an intratumoral ERα expression is positively associated with HER-2 expression and aromatase production by stromal components.

Impact of expression of metabolic genes on patient (pts) outcomes in metastatic colorectal cancer (mCRC): Data from CALGB/SWOG 80405 (Alliance).

224 Background: Metabolic pathways are reprogrammed during CRC development, leading to increased glycolysis, glutaminolysis, and fatty acid synthesis. Understanding the impact of metabolic reprogramming on treatment outcomes is paramount. Hence, we investigated whether the tumor gene expression of 4 selected major metabolic genes ( PKM, SLC2A1 , SLC16A1 , and CAV1 ) could affect treatment response in pts enrolled in the CALGB/SWOG 80405 trial. Methods: 433 mCRC pts treated with either bevacizumab (bev, n = 226) or cetuximab (cet, n = 207) in combination with first-line chemotherapy were analyzed. RNA was isolated from FFPE tumor samples and sequenced on the HiSeq 2500 (Illumina). Overall survival (OS) and progression-free survival (PFS) were compared between groups of pts categorized by tertiles of gene expression (high [H], medium [M] and low [L]). Logrank P -values provide a non-parametric unadjusted assessment of differences. Likelihood ratio tests (LRT) were computed from multivariate Cox proportional hazards models, adjusting for age, sex, ECOG, tumor side, number of metastatic sites, KRAS , CMS, and treatment. Results: PKM gene expression was associated with cet treatment outcomes with PKM- low tumors showing significantly longer PFS and OS (median PFS: 14.3 vs 9.8 vs 8.1 months, L vs M vs H, P < 0.0001, LRT P = 0.011; median OS: 45.9 vs 31.2 vs 20.9 months, P < 0.0001, LRT P = 0.12). Low SLC2A1 was also associated with longer OS in cet-treated pts (32.4 vs 35.8 vs 25.2 months, P = 0.02, LRT P < 0.0001). Similar results were observed in bev-treated pts where low SLC2A1 expressing tumors had longer OS (37.4 vs 26.1 vs 29 months, P = 0.037, LRT P = 0.069) and a non-significant trend for longer PFS (13.1 vs 11 vs 9.5 months, P = 0.076). CAV1 low gene expression was associated with longer OS in cet-treated pts (37.4 vs 34 vs 21.5 months, P = 0.0048, LRT P = 0.013), while no significant associations were found in bev-treated (interaction LRT P = 0.0009). No significant results were observed for SLC16A1 . Conclusions: The intratumoral expression of metabolic genes was prognostic and predictive in mCRC pts treated with first-line therapy. GLUT1 (encoded by SLC2A1 ) and PKM2 (encoded by PKM ) promote aerobic glycolysis of cancer cells, known as Warburg effect, supporting rapid cell proliferation and survival. CAV1 has been shown to be involved in mitochondrial bioenergetics and fatty acid metabolism and to play either a tumor suppressor or oncogenic role depending on the cancer type and stage. Lower expression of SLC2A1 and PKM was associated with improved survival and increased benefit from cet treatment in our cohort. Low CAV1 expression was also associated with increase survival suggesting a cancer-promoting role in mCRC. Our results suggest that targeting cancer cell metabolism through novel inhibitors of the aforementioned pathways may be a promising therapeutic strategy.

CD36 enrichment in HER2-positive mesenchymal stem cells drives therapy refractoriness in breast cancer

BackgroundGrowing evidence shows that the reprogramming of fatty acid (FA) metabolism plays a key role in HER2-positive (HER2 +) breast cancer (BC) aggressiveness, therapy resistance and cancer stemness. In particular, HER2 + BC has been defined as a "lipogenic disease" due to the functional and bi-directional crosstalk occurring between HER2-mediated oncogenic signaling and FA biosynthesis via FA synthase activity. In this context, the functional role exerted by the reprogramming of CD36-mediated FA uptake in HER2 + BC poor prognosis and therapy resistance remains unclear. In this study, we aimed to elucidate whether enhanced CD36 in mesenchymal HER2 + cancer stem cells (CSCs) is directly involved in anti-HER2 treatment refractoriness in HER2 + BC and to design future metabolism-based approaches targeting both FA reprogramming and the “root” of cancer.MethodsMolecular, biological and functional characterization of CD36-mediated FA uptake was investigated in HER2 + BC patients, cell lines, epithelial and mesenchymal CSCs. Cell proliferation was analyzed by SRB assay upon treatment with lapatinib, CD36 inhibitor, or Wnt antagonist/agonist. Engineered cell models were generated via lentivirus infection and transient silencing. CSC-like properties and tumorigenesis of HER2 + BC cells with or without CD36 depletion were examined by mammosphere forming efficiency assay, flow cytometry, cell sorting, ALDH activity assay and xenograft mouse model. FA uptake was examined by flow cytometry with FA BODIPY FL C16. Intratumor expression of CSC subsets was evaluated via multiplex immunostaining and immunolocalization analysis.ResultsMolecular data demonstrated that CD36 is significantly upmodulated on treatment in therapy resistant HER2 + BC patients and its expression levels in BC cells is correlated with FA uptake. We provided evidence of a consistent enrichment of CD36 in HER2 + epithelial-mesenchymal transition (EMT)-like CSCs from all tested resistant cell models that mechanistically occurs via Wnt signaling pathway activation. Consistently, both in vitro and in vivo dual blockade of CD36 and HER2 increased the anti-CSC efficacy of anti-HER2 drugs favoring the transition of the therapy resistant mesenchymal CSCs into therapy-sensitive mesenchymal-epithelial transition (MET)-like epithelial state. In addition, expression of CD36 in intratumor HER2 + mesenchymal CSCs is significantly associated with resistance to trastuzumab in HER2 + BC patients.ConclusionsThese results support the metabolo-oncogenic nature of CD36-mediated FA uptake in HER2 + therapy-refractory BC. Our study provides evidence that targeting CD36 might be an effective metabolic therapeutic strategy in the treatment of this malignancy.

Phenotypic profile of blood monocytes and tumor-associated macrophages in relation to the expression of galectins 1 and 3 in colorectal cancer

Aim. To identify the features of the subpopulation composition of blood monocytes and tumor macrophages in relation to the plasma concentration and intratumoral expression of galectins 1 and 3 in patients with colorectal cancer.Materials and methods. A total of 23 patients with colorectal cancer (ICD C18-20) were examined – 5 men and 18 women (average age 63.8 ± 9.4 years). The control group consisted of healthy volunteers; the comparison group encompassed age- and sex-matched patients with colon adenomas. The study materials included whole blood and tumor biopsies. The concentration of galectins 1 and 3 in the blood was determined by enzyme-linked immunosorbent assay, the content of tumor galectin-1+ and galectin-3+ cells – by immunohistochemistry. Subpopulations of blood monocytes were evaluated by flow cytometry; the macrophage immunophenotypes M1 (CD68+ CD80+ ) and M2d (CD68+ CD206+ ) in tumor tissues were determined using immunofluorescence staining. Statistical processing of the research results was performed by the Jamovi 2.3.21 software package for Windows.Results. In patients with colorectal cancer (CRC), a positive relationship was identified between high plasma concentrations of galectins 1 and 3 and an imbalance of blood monocytes manifested by a decrease in the relative count of classical CD14++CD16- monocytes and, conversely, an increase in the number of non-classical CD14+CD16++ and intermediate CD14+ CD16- cells. The relative numbers of M1 (CD68+CD80+) and M2d (CD68+CD206+) macrophages in CRC tissue samples turned out to be comparable and did not depend on the level of galectins 1 and 3 in the blood and tumor. In patients with colon adenomas, the M2d subpopulation of tumorassociated macrophages was predominant (p = 0.031).Conclusion. In patients with CRC, galectins 1 and 3 have a modulating effect on the ratio of non-classical CD14+CD16++, intermediate CD14+CD16- , and classical CD14++CD16- monocytes in the blood and do not affect the M1/M2d expression profile of tumor-associated macrophages.

Safety and efficacy of trifluridine/tipiracil +/− bevacizumab plus XB2001 (anti-IL-1α antibody): a single-center phase 1 trial

In the tumour microenvironment, IL-1α promotes neoangiogenesis, matrix remodelling, tumour proliferation, chemoresistance, and metastases. Highly expressed in human colorectal cancers, IL-1α is associated with poor prognosis. XB2001, a fully human monoclonal antibody neutralizing IL-1α, was evaluated for safety and preliminary efficacy with trifluridine/tipiracil (FTD/TPI) and bevacizumab in metastatic colorectal cancer patients previously treated with oxaliplatin- and irinotecan-based chemotherapies. This single institution, phase 1 study used a 3 + 3 design to assess XB2001 at doses of 250 mg, 500 mg and 1000 mg every 14 days, associated with FTD/TPI 35 mg/m² (days 1–5 and 8-12, every 28 days) (NCT05201352). The Maximum Tolerated Dose of XB2001 + FTD/TPI was then associated in combination with bevacizumab (5 mg/kg, days 1 and 15). Safety, efficacy, pharmacokinetics and pharmacodynamics were assessed. Seventeen patients (median age: 67.4 years) were enroled. No patient exhibited dose-limiting toxicity at any dose. The most common treatment-related adverse events (TRAE) of any grade (G) were diarrhoea (35.3%), nausea (47.1%) and anaemia (35.3%). G3-4 TRAE were neutropenia (17.6%) hypertension and infection (5.9% each). The RP2D (recommended phase 2 dose) of XB2001 was 1000 mg. The disease control rate was 76%, with 23% of patients achieving an objective response, including one complete response. Response and longer progression-free survival were associated with a decrease in serum IL-6 levels during therapy. High intratumoral IL-1α expression at baseline and CD8/PD-L1 infiltration are associated with a better progression-free survival. The combination of XB2001 with FTD/TPI and bevacizumab is feasible and safe, and showed encouraging clinical activity in chemotherapy-resistant mCRC.

Neoadjuvant or perioperative immunotherapy for resectable melanoma: The need for biomarkers.

Groundbreaking studies have reshaped the treatment landscape for patients with resectable stage ≥IIIB melanoma by demonstrating the benefits of neoadjuvant therapy. Data from the NADINA and SWOG S1801 trials reveal substantial improvements in event-free survival compared to adjuvant therapy alone. These studies employed distinct neoadjuvant immunotherapy approaches -ipilimumab plus nivolumab in NADINA and anti-PD-1 monotherapy in SWOG S1801-highlighting potential differences in efficacy and toxicity. The integration of biomarkers may improve the risk/benefit ratio by enabling personalized treatment selection between ipilimumab plus nivolumab versus anti-PD-1 monotherapy. In metastatic melanoma, molecular biomarkers such as BRAF mutational status and intratumoral PD-L1 expression can help guide treatment decisions; however, their, and other biomarkers', role in the neoadjuvant context has yet to be fully investigated. This commentary underscores the need to investigate whether these molecular markers, along with other biomarkers and clinical parameters, can inform neoadjuvant therapy in resectable stage ≥IIIB melanoma. We propose a coordinated effort involving retrospective analyses of current trials and prospective clinical studies, to define the role of biomarkers. A biomarker-guided approach could optimize efficacy and reduce toxicity, offering personalized treatment options for patients with resectable melanoma. As implementation of neoadjuvant therapy rapidly gains global adoption, we advocate for robust research to ensure that each patient receives the most effective and least toxic therapeutic option.

Prognostic stratification of gastric cancer patients by intratumoral microbiota-mediated tumor immune microenvironment.

Gastric cancer (GC) is a leading cause of cancer-related deaths worldwide, and therapeutic options for advanced GC are limited. Here, we observe that intratumoral microbiota controls chemokine expression, which in turn recruits immune cells into the tumor, and that immune infiltration is strongly associated with patient survival and disease attributes. Furthermore, microbiota regulation of chemokines is differentiated in GC patients with different survival risks. As seen in gastric tumors, in high-survival-risk patients, Pseudomonas regulates CCL4, CXCL9, CXCL10, and CXCL11 accumulation to recruit immune cells such as CD4+ T cells, CD8+ T cells, and M1 macrophages. In low-survival-risk patients, Leptospira regulates CCL4, CCL5, CXCL9, and CXCL10 accumulation to recruit multiple types of immune cells. An independent single-cell dataset of GC verified the relationship between chemokines and immune cells. What's more, chemokines, including CCL4, CCL5, CXCL9, CXCL10, and CXCL11, strongly influence the sensitivity of GC patients to potential drug candidates. This study demonstrates that intratumoral microbiota closely influences the gastric immune microenvironment and that this molding has prognostic heterogeneity, opening avenues for cancer prevention and therapy.

Cytokine-armed pyroptosis induces antitumor immunity against diverse types of tumors

AbstractInflammasomes are defense complexes that utilize cytokines and immunogenic cell death (ICD) to stimulate the immune system against pathogens. Inspired by their dual action, we present cytokine-armed pyroptosis as a strategy for boosting immune response against diverse types of tumors. To induce pyroptosis, we utilize designed tightly regulated gasdermin D variants comprising different pore-forming capabilities and diverse modes of activation, representing a toolbox of ICD inducers. We demonstrate that the electrogenic transfer of ICD effector-encoding plasmids into mouse melanoma tumors when combined with intratumoral expression of cytokines IL-1β, IL-12, or IL-18, enhanced anti-tumor immune responses. Careful selection of immunostimulatory molecules is, however, imperative as a combination of IL-1β and IL-18 antagonized the protective effect of pyroptosis by IFNγ-mediated upregulation of several immunosuppressive pathways. Additionally, we show that the intratumoral introduction of armed pyroptosis provides protection against distant tumors and proves effective across various tumor types without inducing systemic inflammation. Deconstructed inflammasomes thus serve as a powerful, tunable, and tumor-agnostic strategy to enhance antitumor response, even against the most resilient types of tumors.

Impact of T Cell Exhaustion and Stroma Senescence on Tumor Cell Biology and Clinical Outcome of Head and Neck Squamous Cell Carcinomas.

Head and neck squamous cell carcinomas (HNSCC) have an overall poor prognosis, especially in locally advanced and metastatic stages. In most cases, multimodal therapeutic approaches are required and show only limited cure rates with a high risk of tumor recurrence. Anti-PD-1 antibody treatment was recently approved for recurrent and metastatic cases but to date, response rates remain lower than 25%. Therefore, the investigation of the immunological tumor microenvironment and the identification of novel immunotherapeutic targets in HNSCC is of paramount importance. In our study, we used tissue samples of n = 116 HNSCC patients for the immunohistochemical detection of the intratumoral and peritumoral expression of T cell exhaustion markers (PD-1, LAG-3, TIM-3) on tumor infiltration leukocytes (TIL), as well as the expression level of stromal senescence markers (IL-8, MMP-3) on tumor-associated fibroblasts. The clinical parameter of the vitamin D serum status as well as the histopathological HPV infection status of the tumor was correlated with the expression rates of the biomarkers and the overall patient survival. An increased peritumoral and intratumoral expression of the biomarkers PD-1 and TIM-3 significantly correlated with improved overall patient survival. A high peritumoral expression of LAG-3 correlated with better overall survival. A positive HPV tumor status correlated with a significantly elevated expression of PD-1 and TIM-3. Biomarkers of stromal senescence showed no influence on the patient outcome. However, the vitamin D serum status showed no influence on patient outcomes or biomarker expressions. Our study identified PD-1, LAG-3, and TIM-3 as promising targets of a therapeutic strategy targeting the tumor microenvironment in HNSCC, particularly among HPV-positive patients, where a higher expression of these checkpoints correlated with an improved overall survival. These findings support the potential of antibodies targeting these immune checkpoints to enhance treatment efficacy, especially in the context of bispecific targeting.

Interleukin-22 promotes endometrial carcinoma cell proliferation and cycle progression via ERK1/2 and p38 activation.

Endometrial carcinoma (EC) is one of the most common gynecological malignant tumors, but its underlying pathogenic mechanisms are largely obscure. Interleukin-22 (IL-22), one cytokine in the tumor immune microenvironment, was reported to be associated with carcinoma progression. Here, we aimed to investigate the regulation of IL-22 in endometrial carcinoma. Enzyme-linked immunosorbent assay (ELISA) analysis of IL-22 was done in 27 controls and 51 patients with EC. We examined the proliferative potential, cycle progression, and signaling pathways modulated by IL-22 in EC cells. Western blot analysis was performed to investigate the expression of proliferative and cycle-related proteins in EC cells. The effect of IL-22 mediated by interleukin-22 receptor alpha 1 (IL-22RA1) was examined using cell transfection with small interfering RNA (siRNA). In addition, a xenograft tumor model was performed to assess the effect of IL-22 in vivo. We demonstrated significant up-regulation of serum IL-22 concentrations in EC patients (42.59 ± 23.72pg/mL) compared to the control group (27.47 ± 8.29pg/mL). High levels of IL-22 concentrations appear to correlate with malignant clinicopathological features of EC. Treatment with IL-22 promoted cell proliferation and G1/S phase progression in Ishikawa and HEC-1B cells. Western blot analysis revealed that c-Myc, cyclin E1, cyclin-dependent kinase (CDK)2, cyclin D1, CDK4, CDK6, p-extracellular signal-regulated kinase1/2 (p-ERK1/2), and p-p38 were highly expressed in EC cells exposed to IL-22. Moreover, in the EC mice model, we found that giving exogenous IL-22 increased tumor volume and weight. Immunohistochemistry showed that intra-tumor Ki-67 expression was up-regulated upon IL-22 treatment. The IL-22-mediated changes in cell proliferation, cycle progression, and protein expression can be effectively inhibited by the ERK1/2 inhibitor U0126 and the p38 inhibitor SB202190. In addition, the role of IL-22 in EC is receptor-dependent. Our findings suggest that IL-22 promotes endometrial carcinoma cell proliferation and G1/S phase progression by activating ERK1/2 and p38 signaling. Therefore, IL-22 may represent a potential therapeutic target for the treatment of endometrial carcinoma.

Intratumoural expression of dihydropyrimidine dehydrogenase is an independent prognostic factor in resected pancreatic ductal adenocarcinoma treated with adjuvant gemcitabine.

Pancreatic ductal adenocarcinoma (PDAC) is associated with a poor prognosis, and biomarkers to guide treatment decisions in PDAC are generally lacking. Intratumoural expression of dihydropyrimidine dehydrogenase (DPD) is a potential prognostic parameter in patients with PDAC undergoing surgical resection and postoperative chemotherapy. In the present study, DPD was analysed by immunohistochemistry of a tissue microarray platform including a real-world cohort of 495 patients with PDAC who had undergone resection with curative intent at any of three tertiary centres, including Northern, Western and Southeastern regions of Sweden, between 1993 and 2019. DPD level (high/low) was analysed and overall survival associations were assessed in treatment subgroups using a multivariate Cox regression model accounting for potential confounders. In patients who had not received adjuvant chemotherapy (n=182), the median overall survival time was 11.6 months (95% CI 9.6-13.5), compared with 28.8 months (25.0-32.6) among those who had (n=313; log-rank P<0.001). The most common type of chemotherapy was gemcitabine single agent (Gem, n=239) followed by gemcitabine plus capecitabine (GemCape, n=39). Tumour-Node-Metastasis (TNM) stage and DPD expression were statistically significant prognostic parameters in the Gem group (HR 1.19, 95% CI 1.01-1.41, P=0.036), with high expression of DPD linked with worse survival. In addition, tumour grade and TNM stage were statistically significant prognostic factors in the group that did not receive any chemotherapy (P≤0.001). No statistically significant parameters were identified in the GemCape group. Taken together, intratumoural expression of DPD may be considered a prognostic marker for patients with PDAC treated with adjuvant gemcitabine following surgical resection, with low expression levels predicting better survival. Further studies in larger cohorts of patients receiving multi-drug or non-gemcitabine based regimens are warranted.

CXCR2 expression is associated with prostate-specific membrane antigen expression in hepatocellular carcinoma: reappraisal of tumor microenvironment and angiogenesis.

Angiogenesis is a critical component of neoplastic progression, and inflammatory cells within the tumor microenvironment contribute to neoangiogenesis. Prostate-specific membrane antigen (PSMA)is expressedin the neovasculature of various solid tumors, including hepatocellular carcinoma (HCC). Also, CXCR2 + inflammatory cells, including CD15 + neutrophils, play crucial roles in HCC progression.We evaluated the associations between PSMA expression and CXCR2 + inflammatory cells in HCC by immunohistochemistry (IHC). CXCR2 expression and its correlation with PSMA, the PSMA/CD34 ratio, immune markers (CD3, CD15, CD68, and CD163), clinical parameters, and oncologic outcomes were evaluated in 76HCC and background benign liver tissue. PSMA and the PSMA/CD34 ratioshowed a positive correlationwith intratumoralCXCR2,but not with intratumoral CD15. Intratumoral CXCR2 + cell count was positively associated with intratumoral CD3, CD15, CD68, and CD163 expression levels. In the benign compartment, CXCR2 was significantly associated with CD15. Metabolic dysfunction-associated steatotic liver disease (MASLD) risk factors and cirrhosis had an opposite effect on CXCR2 + cell count in benign liver tissue. Higher CD15 + cell count in the benign liver was associated with decreased overall survival (OS) and recurrence-free survival (RFS). In HCC, intratumoral CXCR2 + cell count is associated with PSMA expression. Intratumoral and benign compartments had different CXCR2 + inflammatory cell makeup. The immune microenvironment of HCC appears to differ depending on underlying risk factors. Further investigations are warranted to elucidate PSMA biology and assess the potential utility of CXCR2 IHC in PSMA-targeted theranostics.

Adjuvant rituximab and elevated intratumoural CD8 expression are associated with sustained disease control after radiotherapy in a randomised trial of systemic therapy in early-stage follicular lymphoma

We report extended follow-up of TROG99.03, a randomised phase III trial in early-stage follicular lymphoma (ESFL) including new information on the role of adjuvant rituximab and translational studies. Patients with ESFL were randomised to involved field radiotherapy (IFRT) or IFRT plus 6-cycles cyclophosphamide/vincristine/prednisolone (IFRT+CVP). From 2006 rituximab was added to IFRT+CVP (IFRT+R-CVP). Clinical and multi-omic parameters were evaluated. Findings were validated in two independent ESFL cohorts (99 and 60 patients respectively). Between 2000 and 2012, 150 (75 per arm) patients were recruited. 48% were positron emission tomography (PET)-staged. By protocol, at median follow-up 11.3-years, progression-free survival (PFS) remained superior for IFRT+(R)CVP vs. IFRT (hazard ratio [HR]=0.60, 95% CI=0.37-0.98, p=0.043; 10-year PFS 62% vs. 43%) respectively. Although no significant difference in overall survival was observed (HR=0.44, 95% CI=0.16-1.18, p=0.11, 10-year OS 95% vs. 84%), patients receiving IFRT+(R)CVP experienced fewer composite (histological transformation and death) events (p=0.045). PFS of IFRT+R-CVP-treated patients compared with all other treatments lacking rituximab (IFRT alone plus IFRT+CVP) was superior (HR=0.36, 95% CI=0.13-0.82, p=0.013). Amongst PET-staged patients, PFS differences between IFRT+R-CVP vs. IFRT were maintained (HR=0.38, 95% CI=0.16-0.89, p=0.027) indicating benefit distinct from stage migration. FL-related mutations and BCL2-translocations were not associated with PFS. However, by multivariate analysis elevated CD8A gene expression in diagnostic biopsy tissue was independently associated with improved PFS (HR=0.45, 95% CI=0.26-0.79, p=0.037), a finding confirmed in both ESFL validation cohorts. CD8A gene expression was raised (p=0.02) and CD8+ T-cell density higher within follicles in ESFL vs. advanced-stage FL (p=0.047). Human leucocyte antigen class I specific neoantigens were detected in 43% of patients, suggesting neoantigen-specific CD8+ T-cells have a role in confining the spread of the disease. Adjuvant R-CVP and elevated intratumoural CD8 expression were independently associated with sustained disease control after radiotherapy in ESFL. Cancer Council Victora; National Health and Medical Research Council; Leukaemia Foundation; Mater Foundation.

CD3+ Tumor-Infiltrating Lymphocytes in Breast Carcinoma: Their Prognostic Role and Association With Clinical Parameters.

Background Breast carcinoma cases are rising steadily and represent a major causeof mortality and morbidity in India. In response to breast carcinoma, the immune system is activated, resulting in lymphocyteinfiltration in and around the tumor nests. This interaction between the tumor and immune system is the basisfor studyingtumor-infiltrating lymphocytes (TILs). Despite studies on TILs in breast carcinoma, the role of CD3+TILsin predicting patient outcomes remains underexplored. This study aimed to evaluate TILsin breast carcinoma tissues by analyzing CD3 expression through immunohistochemistry (IHC) and examining its association with various prognostic factors, such as histological grade, clinical stage, lymph node status, and hormone receptor status. Methods A study was conducted on 45 breast carcinoma cases, documenting various clinicopathological parameters. IHCstaining was performed for estrogen receptor (ER), progesterone receptor (PR), human epidermal growth factor (HER2-neu), and CD3 markers on tissue samples. Both intra-tumoral and stromal CD3 TILswere quantified and analyzed in relation to clinicopathological prognostic factors. Results In all 45 breast carcinoma cases, intra-tumoral and stromal CD3 expression was assessed. High stromal CD3 expression is documented in the triple-negative breast tumor. CD3 intra-tumoral expression correlated significantly with tumor size (p < 0.035), ER status (p < 0.036), and PR status (p < 0.036). CD3 stromal expression showed no correlation with any of the prognostic parameters. Conclusion The current study found a strong correlation between CD3 intra-tumoral expression with tumor size, ERand PRstatus. The findings imply that CD3 may be a significant factor in breast carcinoma prognosis. There were more stromal CD3 TILsin triple-negative breast carcinoma (TNBC) cases. TILsought to be examined for their capacity as novel prognostic and predictive indicators, especially in cases of invasive breast cancer, such as triple-negative breast carcinoma.

Intrinsic PD-L1 Degradation Induced by a Novel Self-Assembling Hexapeptide for Enhanced Cancer Immunotherapy.

Programmed death-ligand 1 (PD-L1) is a critical immune checkpoint protein that facilitates tumor immune evasion. While antibody-based PD-1/PD-L1 inhibitors have shown promise, their limitations necessitate the development of alternative therapeutic strategies. This work addresses these challenges by developing a hexapeptide, KFM (Lys-Phe-Met-Phe-Met-Lys), capable of both directly downregulating PD-L1 and self-assembling into a ROS-responsive supramolecular hydrogel. This dual functionality allows Gel KFM to function as a localized drug delivery system and a PD-L1 inhibitor. Loading the hydrogel with mitoxantrone (MTX) and metformin (MET) further enhances the therapeutic effect by combining chemotherapy with PD-L1 downregulation. In vitro and in vivo studies demonstrate significant tumor growth inhibition, increased CD8+ T cell infiltration, and reduced intratumoral PD-L1 expression following peritumoral administration. Mechanistically, KFM promotes PD-L1 degradation via a ubiquitin-dependent pathway. This "carrier-free" delivery system expands the role of supramolecular hydrogels beyond passive carriers to active immunotherapeutic agents, offering a promising new strategy for cancer therapy.

IMMU-50. IMPACT OF SARS-COV-2 MRNA VACCINES ON PD-L1 EXPRESSION IN INTRACRANIAL TUMORS

Abstract Although immune checkpoint inhibitor (ICI) effectiveness is correlated with intra-tumoral PD-L1 expression, there are no clinically available methods to improve sensitivity to ICIs by modulating PD-L1 expression. mRNA vaccines stimulate robust interferon-dependent innate immune activation leading to four-fold increases in PD-L1 expression on peripheral and intratumoral myeloid cells and enhanced sensitivity to immune checkpoint blockade in preclinical models (Sayour, Grippin, et al., NanoLetters, 2018; Mendez-Gomez, et al., Cell, 2024). We hypothesized that mRNA vaccines targeting SARS-COV-2 would similarly enhance PD-L1 expression in intracranial tumors. To test this hypothesis, we utilized institutional databases to identify 5,524 patients at our institution with pathology reports including the term “PD-L1” from August 2020 to November 2023. Pathological data and dates of SARS-COV-2 vaccination were compiled for each patient. Across the entire cohort (n=5,524), receipt of a SARS-COV-2 mRNA vaccine within 100 days of biopsy was associated with a 55% increase in mean tumor proportion score (TPS) (14% vs 8.9%, p=0.029). In the subset of patients with intracranial tumors (n=187), receipt of a SARS-COV-2 mRNA vaccine within 100 days of biopsy was associated with a massive increase in TPS (57% vs 7.2%, p&amp;lt;0.001). To evaluate the impact of this change on clinical outcomes with immunotherapy, we utilized a second institutional database to assemble a cohort of patients with Stage IV melanoma with intracranial metastasis treated with immune checkpoint blockade during the period August 2020 through November 2023. Patients who received a SARS-COV-2 vaccine within 100 days of initiation of ICI (n=10) exhibited numerically improved overall survival compared to those without SARS-COV-2 mRNA vaccine (n=38) (HR 0.50, 95% CI 0.22-1.2, p=0.06). Median overall survival was 545 days among patients without COVID mRNA vaccination and was not met among those with COVID mRNA vaccination. This data supports further investigation of the immune modulating effect of SARS-COV-2 mRNA vaccines in patients with intracranial tumors treated with immune checkpoint blockade.

Natural killer cells are required for the recruitment of CD8+ T cells and the efficacy of immune checkpoint blockade in melanoma brain metastases

Background Brain metastases (BrM) affect up to 60% of patients with metastatic melanoma and are associated with poor prognosis. While combined immune checkpoint blockade of programmed death-1 (PD-1) and cytotoxic...

Spatially Resolved Whole-Transcriptomic and Proteomic Profiling of Lung Cancer and Its Immune Microenvironment According to PD-L1 Expression.

The expression of PD-L1 on tumor cells (TC) is used as an immunotherapy biomarker in lung cancer, but heterogeneous intratumoral expression is often observed. To better understand heterogeneity in the lung cancer tumor microenvironment, we performed proteomic and whole-transcriptomic digital spatial profiling analyses of TCs and immune cells (IC) in spatially matched areas based on tumor PD-L1 expression and the status of the immune microenvironment. We validated our findings using IHC, data from The Cancer Genome Atlas, and immunotherapy cohorts. ICs in areas with high PD-L1 expression on TCs showed more features, indicative of immunosuppression and exhaustion, than ICs in areas with low PD-L1 expression on TCs. TCs highly expressing PD-L1 within immune-inflamed areas showed upregulation of proinflammatory processes, whereas TCs highly expressing PD-L1 within immune-deficient areas showed upregulation of various metabolic processes. Using differentially expressed genes of TCs between the immune-inflamed and immune-deficient areas, we identified a prognostic gene signature for lung cancer. In addition, we found that a high ratio of CD8+ cells to M2 macrophages predicted favorable outcomes in patients with PD-L1-expressing lung cancer after immune checkpoint inhibitor therapy. Overall, this study demonstrates that TCs and ICs have distinct spatial features within the lung tumor microenvironment that are related to tumor PD-L1 expression and IC infiltration.

Tissue and Imaging Biomarkers of Response to Neoadjuvant Nivolumab or Nivolumab plus Ipilimumab in Patients with Resectable Hepatocellular Carcinoma

Introduction: Perioperative immunotherapy has shown promise in some patients with early-stage hepatocellular carcinoma (HCC). This study examined tissue and imaging biomarkers associated with pathologic response in a phase II clinical trial in patients with resectable HCC. Methods: Analysis included 18 patients with biopsy-proven resectable HCC treated with neoadjuvant nivolumab plus ipilimumab or nivolumab alone in a phase II clinical trial at MD Anderson Cancer Center (NCT03222076). Liver MRE (to measure tissue fibrosis) and biopsies (to evaluate immune activation markers) were obtained serially pretreatment and after completing neoadjuvant immunotherapy. A major pathologic response (MPR) was defined as tumor necrosis of more than 70%. Data comparing patients with MPR versus those without were summarized using descriptive statistics and compared using the Wilcoxon rank-sum test. Results: Patients with MPR after neoadjuvant immunotherapy tended to have larger tumors (mean 9.52 vs. 4.99 centimeters; p = 0.050). They had a significant reduction in tumor size posttreatment (14.67% reduction vs. 9.15% increase in size; p = 0.042) and a nonsignificant decrease in serum AFP (−24.20% vs. −14.00%; p = 0.085). Further, patients with MPR had a greater increase in intratumoral expression levels of CD8 (26.92% vs. −0.04%; p = 0.026), granzyme B (15.56% vs. −2.24%; p = 0.011), and PD-1 (20.17% vs. 0.40%; p = 0.048) but not PD-L1 (7.69% vs. 0.57%; p = 0.26). For imaging biomarkers, tumor and liver fibrosis were comparable before and after neoadjuvant therapy in patients with MPR versus nonresponders. Conclusion: Changes in tumor size, immune cell infiltration, and immune cell activation are candidate predictive markers of pathologic response to neoadjuvant immunotherapy in patients with resectable HCC.