High CD44 Research Articles

Outcomes Associated With ABCG2 and CD133 Expression in Patients With Gastric Cancer After Surgical Resection

Objectives: Adenosine triphosphate-binding cassette subfamily G member 2 (ABCG2) and CD133 are recognized stem cell markers of gastric cancer. Extensive research has examined the significance of these markers in different types of cancers and their impact on prognoses, linking them to unfavorable clinical outcomes in various tumors. However, the prognostic value of these markers for gastric cancer remains unclear. We investigated the expression of ABCG2 and CD133 and their relationship with clinical outcomes in gastric cancer.Methods: ABCG2 and CD133 expression levels were analyzed, using immunohistochemistry and tissue microarrays, in tumor samples from 459 patients who underwent surgical resections due to gastric cancer. ABCG2 and CD133 expression levels were defined by intensity and dichotomized as medians. The associations among the expression levels of these markers, disease severity, and patient survival were also determined.Results: In the 411 patients for whom we analyzed the expression levels of these markers, 74.9% and 80.5% were found to have high levels of ABCG2 and CD133, respectively. High expression levels of ABCG2 and CD133 were more commonly observed in well-differentiated (<i>p</i><0.001 and <i>p</i>=0.004, respectively) and intestinal lesions (<i>p</i><0.001 and <i>p</i>=0.002, respectively). High ABCG2 expression correlated with improved survival outcomes, whereas high CD133 expression was associated with poorer outcomes. Cox regression analysis confirmed that stage, high ABCG2 (overall survival [OS]: hazard ratio [HR], 0.61; 95% confidence interval [CI], 0.41–0.91; <i>p</i>=0.015; recurrencefree survival [RFS]: HR, 0.55; 95% CI, 0.34–0.88; <i>p</i>=0.012), and CD133 expression (OS: HR, 1.59; 95% CI, 1.00–2.51; <i>p</i>=0.049; RFS: HR, 2.29; 95% CI, 1.21–4.34; <i>p</i>=0.011) were predictors of survival. A subgroup analysis indicated that ABCG2 expression was also associated with an improved RFS rate in patients who received systemic chemotherapy.Conclusions: High ABCG2 expression and low CD133 expression in tumors correlated with improved survival outcomes in post-resection patients with gastric cancer, suggesting their potential utility as prognostic biomarkers.

Expression and clinical significance of PD-L1 and infiltrated immune cells in the gastric adenocarcinoma microenvironment.

Programmed death-ligand 1 (PD-L1) is a crucial negative costimulatory molecule expressed on both tumor and immune cells. It binds to programmed death-1, facilitating tumor escape. Tumor-infiltrating immune cells play a vital role in this process. However, the clinical relationship between PD-L1 expression and tumor-infiltrating immune cells remains uncertain. Immunohistochemistry (IHC) was utilized to assess PD-L1 expression and TIIC markers (CD3, CD4, CD8, CD19, CD31, CD68, CD11c, CD56, and α-smooth muscle actin) in gastric adenocarcinoma tissues from 268 patients. The aim was to explore the prognostic significance of PD-L1 and the infiltration of different immune cell types. The study analyzed overall survival and the correlations between PD-L1 expression, immune cell infiltration, and clinicopathological characteristics. Among the 268 patients, 52 (19.40%) exhibited high PD-L1 expression on tumor cells (TPD-L1), while 167 (62.31%) displayed high PD-L1 expression on immune cells (IPD-L1). Patients with high IPD-L1 expression showed improved survival compared to those with low IPD-L1 expression (P = .028). High TPD-L1 expression associated with various clinicopathological features, such as larger tumor size, poorer differentiation, deeper invasion depth, and higher tumor stage. Conversely, patients with high IPD-L1 expression exhibited shallower tumor invasion and lower mortality rates. Univariate analysis indicated that superficial tumor infiltration, absence of lymph node and distant metastasis, low tumor stage, high IPD-L1 expression, and elevated CD8 and CD19 expression were associated with a reduced risk of tumor progression. Multivariate analysis revealed that patients with high IPD-L1 and CD8 expression or high TPD-L1 and low CD31 expression experienced significantly better overall survival than patients with other combinations. The findings indicate that patients with high PD-L1 expression in immune cells have a substantially improved prognosis. Additionally, the combination of PD-L1 with CD8 or CD31 expression status can serve as an indicator of prognosis in patients with gastric adenocarcinoma.

Towards a Decision Engine for Therapeutic Optimization of Relapsed Refractory Multiple Myeloma

Introduction Substantial progress in the treatment of Multiple Myeloma (MM) extends survival for many patients (Pts), even after multiple relapses, owing to a broad and rapidly extending therapeutic arsenal, with major advances in the arena of bispecific antibodies and CART therapy. However, this also creates an increasingly complex challenge in selecting optimal therapeutic modalities for each patient, as current guidelines rely on empirical considerations. To address this, our study employs a population-scale single cell genomics database of over 250 patient samples covering all disease stages and cycles of treatment with complete patient medical records and machine learning approaches to analyze molecular signatures of myeloma cells and bone marrow immune microenvironment. Methods This study constitutes a meta-trial of RRMM patients who underwent single-cell RNA sequencing (scRNA-seq) between 6.2017 and 6.2023 in our lab. We gathered comprehensive demographic and myeloma clinical data, with a particular focus on therapeutic history and drug refractoriness, defined based on IMWG criteria (progression on or within 60 days from treatment). Our clinical scRNA-seq pipeline, includes a tailored protocol involving index sorting of CD38+ CD138+ positive cells for myeloma plasma cells (PCs) (Ledergor et al, Nat Med 2018; Cohen et al Nat Med 2020), together with CD45+ sorting and scRNA-seq cells from the tumor microenvironment for to identify tumor -immune molecular signatures associated with drug resistance. Results A total of 243 patient samples were included in the study, comprising RRMM (N=128), NDMM (N=21), SMM (N=9), and MGUS (N=4) patients with clinical annotation. Among RRMM patients, the median age was 72 (range 40-89), and 59% exhibited high-risk FISH cytogenetics (t(4:14), del17p, t(14:16), t(14:20), +1q21), while 17% had double-hit myeloma. Refractoriness to specific drugs was observed, such as bortezomib (49%), carfilzomib (27%), lenalidomide (49%), pomalidomide (33%), daratumumab (49). In total, we sequenced 158,444 myeloma/plasma cells, with an average of 880 cells per patient, along with 800 CD45+ cells. By using plasma cells from 11 healthy donors as a reference, we calculated transcriptional changes for each patient, determining the upregulated and downregulated genes profile. Clustering the patient's tumor profiles revealed 7 main tumor archetypes [TA] defined by the expression of 8 gene modules. Refractoriness score, defined as the average number of drugs to which myeloma is refractory, exhibited variations across different tumor archetypes. Notably, the expression levels of several tumor drivers and crucial targets of novel immunotherapies also showed diversity among the tumor archetypes. For instance, TA#6, primarily comprising newly diagnosed patients, displayed lower expression of GPRC5D. Conversely, in TA#1, which consisted of ultra-refractory patients with high MYC and CD47 expression, both GPRC5D and TNFRSF17 (BCMA) were downregulated. Examination of bone marrow CD45+ immune cells revealed a striking bimodal immune composition, characterized by one subtype with increased T-cell abundance and another enriched with myeloid cells. Each immune cell subtype contributed to the drug responsiveness score and provided additional insights complementary to the tumor cells' profile. Further clinical and transcriptional correlations involving both MM cells and immune cells will be presented at the meeting. Conclusions We constructed a clinically-annotated transcriptional matrix revealing the blueprint of relapsed refractory myeloma. This novel decision engine provides a basis for optimizing treatment selection by considering both tumor and tumor microenvironment characteristics. By incorporating critical information on drug resistance patterns and expression of key targets like GPRC5D, TNFRSF17 (BCMA) and FcRH5, we enable precision medicine approaches for improved management of relapsed refractory myeloma. These findings open avenues for tailored and more effective therapeutic strategies, promising better outcomes for patients with relapsed refractory myeloma.

The Interaction between Collagen 1 and High Mannose Type CD133 Up-Regulates Glutamine Transporter SLC1A5 to Promote the Tumorigenesis of Glioblastoma Stem Cells.

Targeting the niche components surrounding glioblastoma stem cells (GSCs) helps to develop more effective glioblastoma treatments. However, the mechanisms underlying the crosstalk between GSCs and microenvironment remain largely unknown. Clarifying the extracellular molecules binding to GSCs marker CD133 helps to elucidate the mechanism of the communication between GSCs and the microenvironment. Here, it is found that the extracellular domain of high mannose type CD133 physically interacts with Collagen 1 (COL1) in GSCs. COL1, mainly secreted by cancer-associated fibroblasts, is a niche component for GSCs. COL1 enhances the interaction between CD133 and p85 and activates Akt phosphorylation. Activation of Akt pathway increases transcription factor ATF4 protein level, subsequently enhances SLC1A5-dependent glutamine uptake and glutathione synthesis. The inhibition of CD133-COL1 interaction or down-regulation of SLC1A5 reduces COL1-accelerated GSCs self-renewal and tumorigenesis. Analysis of glioma samples reveals that the level of COL1 is correlated with histopathological grade of glioma and the expression of SLC1A5. Collectively, COL1, a niche component for GSCs, enhances the tumorigenesis of GSCs partially through CD133-Akt-SLC1A5 signaling axis, providing a new mechanism underlying the cross-talk between GSCs and extracellular matrix (ECM) microenvironment.

ALDH2 dysfunction and alcohol cooperate in cancer stem cell enrichment.

The alcohol metabolite acetaldehyde is a potent human carcinogen linked to esophageal squamous cell carcinoma (ESCC) initiation and development. Aldehyde dehydrogenase 2 (ALDH2) is the primary enzyme that detoxifies acetaldehyde in the mitochondria. Acetaldehyde accumulation causes genotoxic stress in cells expressing the dysfunctional ALDH2E487K dominant negative mutant protein linked to ALDH2*2, the single nucleotide polymorphism highly prevalent among East Asians. Heterozygous ALDH2*2 increases the risk for the development of ESCC and other alcohol-related cancers. Despite its prevalence and link to malignant transformation, how ALDH2 dysfunction influences ESCC pathobiology is incompletely understood. Herein, we characterize how ESCC and preneoplastic cells respond to alcohol exposure using cell lines, three-dimensional organoids and xenograft models. We find that alcohol exposure and ALDH2*2 cooperate to increase putative ESCC cancer stem cells with high CD44 expression (CD44H cells) linked to tumor initiation, repopulation and therapy resistance. Concurrently, ALHD2*2 augmented alcohol-induced reactive oxygen species and DNA damage to promote apoptosis in the non-CD44H cell population. Pharmacological activation of ALDH2 by Alda-1 inhibits this phenotype, suggesting that acetaldehyde is the primary driver of these changes. Additionally, we find that Aldh2 dysfunction affects the response to cisplatin, a chemotherapeutic commonly used for the treatment of ESCC. Aldh2 dysfunction facilitated enrichment of CD44H cells following cisplatin-induced oxidative stress and cell death in murine organoids, highlighting a potential mechanism driving cisplatin resistance. Together, these data provide evidence that ALDH2 dysfunction accelerates ESCC pathogenesis through enrichment of CD44H cells in response to genotoxic stressors such as environmental carcinogens and chemotherapeutic agents.

Oxidized ATM governs stemness of breast cancer stem cell through regulating ubiquitylation and acetylation switch

Cancer stem cells (CSCs), as parts of tumor initiation cells, play a crucial role to tumorigenesis, development and recurrence. However, the complicated mechanisms of CSCs to adapt to tumor microenvironment and its stemness maintenance remains unclear. Here, we show that oxidized ATM, a hypoxia-activated cytoplasm ATM, acts a novel function to maintain CSC stemness in triple-negative breast cancer cells (BCSCs) via regulating histone H4 acetylation. Mechanistically, oxidized ATM phosphorylates TRIM21 (a E3 ubiquitin ligase) serine 80 and serine 469. Serine 80 phosphorylation of TRIM21 is essential for the ubiquitination activity of TRIM21. TRIM21 binds with SIRT1 (one of deacetylase), resulting in ubiquitylation-mediated degradation of SIRT1. The reduced SIRT1 leads to increase of histone H4 acetylation, thus facilitating CSC-related gene expression. Clinical data verify that high level of ATM in breast tumors is positively correlated with malignant grade, and is closely related with low SIRT1, high p-TRIM21, and high CD44 expression. In conclusion, our study provides a novel mechanism by which oxidized ATM governing BCSCs stemness and reveals an important link among oxidized ATM, histone acetylation, and BCSCs maintenance.

Immunohistochemical diagnosis of tumor-associated macrophages in patients with muscle-invasive bladder cancer after radical cystectomy

BACKGROUND: Bladder cancer is a serious problem of oncourology. The gold standard of treatment for muscle-invasive bladder cancer is radical cystectomy with previous neoadjuvant chemotherapy. Unfortunately, the effectiveness of radical treatments is severely limited in the long term. For this reason, research in the field of predicting survival can significantly improve long-term oncological results. The determination of the levels of macrophages associated with the tumor appears promising.
 AIM: to determine the effect of the expression levels of macrophages associated with a tumor on survival rates in patients diagnosed with muscle-invasive bladder cancer after radical cystectomy.
 MATERIALS AND METHODS: the study was conducted on the basis of the Clinic of the Bashkir State Medical University in the period from 01.05.2021 to 01.07.2023. The study involved 66 patients with an established diagnosis of muscle-invasive bladder cancer. After surgical treatment, histological and immunohistochemical studies were performed to determine CD68 and CD163 levels. After 24 months, a survival analysis was performed to determine the levels of general, tumor-specific and relapse-free survival and the construction of Kaplan–Mayer graphs.
 RESULTS: According to the results of the analysis, there was a significant decrease in survival in groups with high CD68 and CD163 expression rates (p 0.05). In the study groups, there was a significantly significant correlation between high levels of CD68 and CD163 (p 0.05).
 CONCLUSIONS: CD68 and CD163 can act as independent markers of predicted survival in patients with muscle-invasive bladder cancer after radical cystectomy.

CD15 Is a Risk Predictor and a Novel Target in Clear Cell Renal Cell Carcinoma

Introduction: Tumor cells use adhesion molecules like CD15 or sialylCD15 (sCD15) for metastatic spreading. We analyzed the expression of CD15 and sCD15 in clear cell renal cell carcinoma (ccRCC) regarding prognosis. Methods: A tissue microarray containing tissue specimens of 763 patients with ccRCC was immunohistochemically stained for CD15 and sCD15, their expression quantified using digital image analysis, and the impact on patients’ survival analyzed. The cell lines 769p and 786o were stimulated with CD15 or control antibody in vitro and the effects on pathways activating AP-1 and tumor cell migration were examined. Results: ccRCC showed a broad range of CD15 and sCD15 expression. A high CD15 expression was significantly associated with favorable outcome (p < 0.01) and low-grade tumor differentiation (p < 0.001), whereas sCD15 had no significant prognostic value. Tumors with synchronous distant metastasis had a significantly lower CD15 expression compared to tumors without any (p < 0.001) or with metachronous metastasis (p < 0.01). Tumor cell migration was significantly reduced after CD15 stimulation in vitro, but there were no major effects on the activating pathways of AP-1. Conclusion: CD15, but not sCD15, qualifies as a biomarker for risk stratification and as an interesting novel target in ccRCC. Moreover, the data indicate a contribution of CD15 to metachronous metastasis. Further research is warranted to decipher the intracellular pathways of CD15 signaling in ccRCC in order to characterize the CD15 effects on ccRCC more precisely.

IMMU-22. BLOCKADE OF CD47 RESULTS IN METABOLIC REPROGRAMMING TO ENHANCE IMMUNE CELL-MEDIATED CYTOTOXICITY OF GLIOBLASTOMA

Abstract Glioblastoma (GBM) is the most aggressive and malignant brain tumor. There is growing interest in using immunotherapy to treat GBM, however, clinical trials with immune checkpoints have shown little efficacy, likely due to significant GBM-associated systemic and intra-tumoral immunosuppression. The expression of the transmembrane protein CD47 contributes significantly to immunosuppression limiting innate and adaptive anti-tumor responses. Our new data shows that patient biopsies showed strong immunoreactivity to CD47 in GBM compared to normal adjacent tissue. Furthermore, high CD47 expression in GBM patients resulted in poor survival, indicating that CD47 may be a potential target for GBM treatment. Beyond the “don’t eat me signal”, CD47 facilitates its intracellular signaling through PLIC1 and it still unknown how CD47-related can influence metabolic reprogramming in the tumor microenvironment. Previous studies that upregulated fatty acid oxidation (FAO) provide GBM cells with metabolic plasticity to accommodate its dynamic nutrient microenvironment. Respirometry data revealed that blocking CD47 in murine cell line (CT2A) reduces mitochondrial function and ATP production by over 40-50% respectively (p*&amp;lt; 0.02). The reduction in mitochondrial respiration is linked to an over 50% reduction in FAO (*p&amp;lt; 0.004). This was associated with significant decreases in CPT1a, FASN, ATGL, and CD36 indicating a reduction in FA metabolism mediators. On the other hand, blocking CD47 on murine microglia (SIMA9), showed an opposite result from cancer cells, with increasing mitochondrial respiration and FAO. Initial shows differential responses may be due to the engagement of PLIC1 to CD47. Furthermore, blocking CD47 on microglia increased three-fold of the immune cell-mediated GBM cell cytotoxicity (*p&amp;lt; 0.005), suggesting that metabolic reprogramming associated with CD47 blockade could result in the improvement of immune adaptive responses in the GBM microenvironment. Taken together, our data indicated that CD47 blockade may be a prospective treatment to reduce GBM metabolic plasticity and increase microglia-mediated GBM killing.

CD20low/CD68high a Promising Microenvironnement Profile Identifying Classical Hodgkin Lymphoma Patients with Poor Outcome a Lysa Study

Introduction Although progression free survival and overall survival of patients with Hodgkin lymphoma (HL) has improved in the past 10 years, 15 % of patients will fail to conventional therapy and die of their lymphoma. The search of new prognostic factors for identifying these high risk patients at diagnosis of HL remains challenging in PET-guided strategies developed to improve the outcome HL patients while reducing treatment toxicity The aim of this study was therefore to assess the impact of baseline tumor microenvironnement in a large cohort of HL patients prospectively treated with upfront escalated BEACOPP in a randomized phase III clinical trial evaluating a PET-driven strategy (AHL 2011, NCT01358747) and to compare its prognostic value with other clinicopathological markers. Material and Methods Tumoral material was collected from HL patients prospectively enrolled in the AHL2011 study from LYSA centers in France and Belgium. The AHL2011 study was designed to evaluate in 16-60y HL patients with Ann Arbor stage III, IV or high risk IIB, a de-escalade PET-driven strategy after 2 cycles of BEACOPPesc (PET2) randomly compared to a standard treatment not driven by PET delivering 6 cycles of BEACOPPesc. The AHL2011 strategy was shown to safely guide treatment of advanced HL patients allowing using ABVD in early responders to BEACOPPesc (PET2 negative) reducing toxicities without impairing disease control (Casasnovas et al, Lancet Oncol 2019, JCO 2022). The tumor microenvironnement (TME) was analyzed on formalin fixed paraffin embedded diagnostic tissue biopsy obtained before treatment by morphological evaluation on standard staining on whole slides (% polynuclear eosinophils, % lymphocytes, % plasmocytes, % histiocytes), and immunohistochemistry (IHC) scoring (score 0-1-2-3) for CD20, CD3, CD4, CD8, CD68-TAMs (tumor-associated macrophages), CD163 (n=680) and EBERS (n= 634). Additional staining were done on Tissue microarray (TMA n=409) for PD-1, PD-L1, TIM3, GATA3, CD45R0, TBET and were centrally reviewed. Computational analysis was used for the TMA analysis using Tissu Studio software (Definiens). For each marker, a H-score was calculated (stained cells x 1, 2 or 3 according to the intensity of staining divided by the total number of cells x100) Results 680 patients were included on the whole slides analyses and 409 for those on the TMA analyses. Patients included had similar characteristics to the remaining patients of AHL2011 not included here. Among all the microenvironnement biomarkers tested only CD20 and CD68 had prognosis value. In univariate analysis, high CD20 H-score was associated with a favorable PFS (HR=0.43, 95%CI 0.22-0.86), while patients having high CD68 H-score had unfavorable PFS (HR=2.29, 95%CI 1.29-4.05). Then, the patients with a combined CD20 low/CD68high TME (n= 239, 47%) had a significant lower PFS compared to other groups (HR=2.46, 95%CI 1.48-4.09; p=0.004) (figure 1). In multivariate analysis including all relevant variables (Bulky disease / IPS / TMTV (total metabolic volume) / PET2 /PET4 / combination CD20 CD68 / % of tumor cells /EBV status / B symptoms), only High TMTV &amp;gt;220ml (HR = 2.09, p =0.017), PET4 positivity (HR= 7.06 ; p &amp;lt; 0.0001) and the CD20 low/CD68high profile (HR=1.95, p=0.025) had an independant prognosis value on PFS. Patients harboring both a TME depleted in CD20 and enriched in CD68, had peculiarities. Indeed, they had significantly more B symptoms (78.2% vs 64.2%, p&amp;lt;0.001), higher median TMTV (270 vs 163ml, p&amp;lt;0.001), were more frequently EBERs positive (23.6 vs 12.7%, p=0.002), had more frequently lymphopenia (38.5 vs 18.2%, p&amp;lt;0.001) and high IPS (69.2 vs 53%, p&amp;lt;0.001). Finally, patients with a CD20low/CD68high profile, had a higher median tumor cells PD-L1 H-score compared to other patients (39.7 vs 7.4, p&amp;lt;0.001). Conclusion Altogether these results demonstrate in a large PET-guided phase III trial (AHL2011), the interest of analyzing CD20 and CD68 expressions within the tumor microenvironnement to better evaluate the risk of treatment failure prior to therapy in patients with advanced HL. The prognosis value of the CD20/CD68 profile is independant of those of the baseline PET metrics (TMTV), and the early reponse to treatment. The enrichment of highly positive PD-L1 tumor cells in patients with CD20 low/CD68high TME suggests that PD-1 blockers could be a good therapeutic option in frontline treatment of this poor prognosis group.

GRP78 is Overexpressed in Non-small Cell Lung Cancer Tissues and is Associated with High VEGF Expression in Squamous Cell Carcinoma: A Pilot Study.

Neovascularization is essential for the growth and progression of tumor tissues. GRP78 is frequently overexpressed in various cancers and has been suggested as a proangiogenic factor. This study aimed to investigate the expression levels of GRP78 and to test for significant relationships with the angiogenic markers, VEGF, and CD31. In this study, paraffin-embedded NSCLC tissue samples (71 adenocarcinomas and 23 squamous cell carcinoma) were retrospectively collected from 94 patients with NSCLC. The expressions of VEGF, CD31, and GRP78 were determined by immunohistochemistry. High expression levels of VEGF and GRP78 were observed in 65 and 74 cases, respectively. Thirty-six patients expressed high CD31 levels. Adenocarcinomas expressed higher levels of the three proteins than squamous cell carcinomas (p-value < 0.05). Moreover, a statistically significant association was found between the expression levels of VEGF and CD31 (p-value = 0.001) and VEGF and GRP78 (p-value=0.028). GRP78 overexpression was revealed in most of the investigated samples. The positive association between VEGF and GRP78 may indicate the proangiogenic role of GRP78 in lung cancer. Moreover, the positive association between VEGF and CD31 expression levels suggests that VEGF may cooperate with CD31 to promote angiogenesis in NSCLC.

Immune microenvironment of intimal sarcomas: Adaptive immune resistance with potential therapeutic implications.

Intimal sarcomas are rare, aggressive neoplasms that arise from large blood vessels. Characterization of the tumor immune microenvironment may suggest new treatment strategies. Seventeen specimens from 7 patients were labeled by immunohistochemistry for programmed cell death 1 ligand 1 (PD-L1), CD45, CD8, CD4, FOXP3, CD20, CD68, and LAG3. The immune cell density was scored as a percentage of the tumor area (1+ [<5%], 2+ [5%-50%], 3+ [>50%]); PD-L1 expression was scored on tumor cells and on intratumoral immune cells. Immune marker density was quantified using image analysis software. All intimal sarcomas showed immune cell infiltration (41% were 1+, 53% were 2+, 6% were 3+). Tumor and immune cell PD-L1 labeling was seen in 35% and 76% of cases, respectively; PD-L1+ intimal sarcomas had higher CD45+, CD8+, FOXP3+, CD68+, and leukocyte activation gene 3 (LAG3)+ cell densities (P ≤ .01). Similarly, PD-L1 expression on immune cells correlated with higher densities of CD8+ and FOXP3+ cells (P < .04). Higher LAG3+ cell density correlated with higher CD68+ cell density and necrosis (P < .05). One patient with prolonged survival had the highest immune cell density and PD-L1 expression. These data show that intimal sarcomas have an active tumor microenvironment with an adaptive pattern of PD-L1 expression. Our results suggest that immunotherapy may be an effective treatment option.

Autoreactive B cells in rheumatoid arthritis include mainly activated CXCR3+ memory B cells and plasmablasts.

Many autoimmune diseases (AIDs) are characterized by persistence of autoreactive B cell responses which is often directly implicated in disease pathogenesis. How and why these cells are generated or how they are maintained for years is largely unknown. Rheumatoid arthritis is among the most common AIDs and characterized by autoantibodies recognizing proteins with post-translational modifications (PTMs). This PTM-directed, autoreactive B cell compartment is ill defined. Here, we visualized the B cell response against the three main types of PTM antigens implicated in RA by spectral flow cytometry. Our results showed extensive cross-reactivity of PTM-directed B cells against all three PTM antigens (citrulline, homocitrulline and acetyllysine). Unsupervised clustering revealed several distinct memory B cell (mBC) populations. PTM-directed cells clustered with the most recently activated, class-switched mBC phenotype, expressing high CD80, low CD24 and low CD21. Notably, patients also harbored large fractions of PTM-directed plasmablasts (PB). Both PTM-directed mBC and PB showed high expression of CXCR3, a receptor for chemokines abundantly present in arthritic joints. Together, our data provide detailed insight into the biology of B cell autoreactivity and its remarkable, seemingly exhaustless persistence in a prominent human AID.

The oesophageal adenocarcinoma tumour immune microenvironment dictates outcomes with different modalities of neoadjuvant therapy - results from the AGITG DOCTOR trial and the cancer evolution biobank.

A plateau in treatment effect can be seen for the current 'one-size-fits-all' approach to oesophageal adenocarcinoma (OAC) management using neoadjuvant chemoradiotherapy (nCRT) or chemotherapy (nCT). In OAC, the tumour microenvironment (TME) is largely immunosuppressed, however a subgroup of patients with an immune-inflamed TME exist and show improved outcomes. We aimed to understand the overall immune-based mechanisms underlying treatment responses and patient outcomes in OAC, and in relation to neoadjuvant therapy modality. This study included 107 patients; 68 patients were enrolled in the Australian Gastro-Intestinal Trials Group sponsored DOCTOR Trial, and 38 patients were included from the Cancer Evolution Biobank. Matched pre-treatment and post-treatment tumour biopsies were used to perform multi-modality analysis of the OAC TME including NanoString mRNA expression analysis, multiplex and single colour immunohistochemistry (IHC), and peripheral blood mononuclear cell analysis of tumour-antigen specific T cell responses. Patients with the best clinicopathological outcomes and survival had an immune-inflamed TME enriched with anti-tumour immune cells and pathways. Those with the worst survival showed a myeloid T regulatory cell enriched TME, with decreased CD8+ cell infiltration and increased pro-tumour immune cells. Multiplex IHC analysis identified that high intra-tumoural infiltration of CD8+ cells, and low infiltration with CD163+ cells was associated with improved survival. High tumour core CD8+ T cell infiltration, and a low tumour margin infiltration of CD163+ cells was also associated with improved survival. nCRT showed improved survival compared with nCT for patients with low CD8+, or high CD163+ cell infiltration. Poly-functional T cell responses were seen with tumour-antigen specific T cells. Overall, our study supports the development of personalised therapeutic approaches based on the immune microenvironment in OAC. Patients with an immune-inflamed TME show favourable outcomes regardless of treatment modality. However, in those with an immunosuppressed TME with CD163+ cell infiltration, treatment with nCRT can improve outcomes. Our findings support previous studies into the TME of OAC and with more research, immune based biomarker selection of treatment modality may lead in improved outcomes in this deadly disease.

The invasive margin of early-stage human colon tumors is infiltrated with neutrophils of an antitumoral phenotype.

Neutrophils infiltrate several types of cancer; however, whether their presence is associated with disease progression remains controversial. Here, we show that colon tumors overexpress neutrophil chemoattractants compared to healthy tissues, leading to their recruitment to the invasive margin and the central part of colon tumors. Of note, tumor-associated neutrophils expressing tumor necrosis factor α, which usually represents an antitumoral phenotype, were predominantly located in the invasive margin. Tumor-associated neutrophils from the invasive margin displayed an antitumoral phenotype with higher ICAM-1 and CD95 expression than neutrophils from healthy adjacent tissues. A higher neutrophil/lymphocyte ratio was found at later stages compared to the early phases of colon cancer. A neutrophil/lymphocyte ratio ≤3.5 predicted tumor samples had significantly more neutrophils at the invasive margin and the central part. Moreover, tumor-associated neutrophils at the invasive margin of early-stage tumors showed higher ICAM-1 and CD95 expression. Coculture of colon cancer cell lines with primary neutrophils induced ICAM-1 and CD95 expression, confirming our in situ findings. Thus, our data demonstrate that tumor-associated neutrophils with an antitumoral phenotype characterized by high ICAM-1 and CD95 expression infiltrate the invasive margin of early-stage colon tumors, suggesting that these cells can combat the disease at its early courses. The presence of tumor-associated neutrophils with antitumoral phenotype could help predict outcomes of patients with colon cancer.

Spatial Proteome Analysis Identifies Lymphocyte CD44 as a Biomarker Associated with SBRT Resistance in Early-Stage Non-Small Cell Lung Cancer

To discover and validate spatially-resolved protein markers associated with resistance to SBRT in early-stage NSCLC patients. We initially evaluated a discovery cohort of 44 early-stage NSCLC patients treated with SBRT as first-line treatment at the Shandong cancer hospital. Using the GeoMx DSP system, 71 proteins were measured in five molecular compartments (tumor, leukocyte, lymphocyte, macrophage, and stroma) on pre-treatment samples. Candidate biomarkers were orthogonally validated with the Gem AQUA method of quantitative immunofluorescence (QIF). For internal independent cohort validation, we assessed pre-treatment samples derived from 150 NSCLC patients who receive radiotherapy. We further analyzed 100 radiotherapy untreated patients with operable NSCLC to address prognostic significance. Using continuous log-scaled data, we identified CD44 expression in the lymphocyte compartment (CD3+) as a novel predictor of poor progression-free survival (PFS) (multivariate HR = 7.323, p = 0.0079) and overall survival (OS) (multivariate HR = 8.65, p = 0.028) in the discovery set. High CD44 expression in the tumor compartment (pan-cytokeratin, CK+) predicted significantly shorter OS (multivariate HR = 2.208, p = 0.0212), with no significant difference in PFS. We validated by QIF that lymphocyte CD44 levels were associated with resistance to SBRT therapy and prognostic for poor outcomes. Using QIF in an independent radiotherapy treated cohort, we validated that CD44 levels in the lymphocyte compartment were associated with poor PFS and OS. High lymphocyte cell CD44 was not prognostic in non-radiotherapy-treated cohort. Using DSP data, intratumoral regions with elevated lymphocyte cell CD44 expression showed prominent upregulation of CD127, ARG1 and VISTA in the discovery Cohort. In conclusion, we identified and validated lymphocyte cell CD44 as a biomarker indicative of resistance to SBRT or radiotherapy in patients with NSCLC. Further evaluation is warranted to address the predictive value of lymphocyte cell CD44 in multi-institutional studies and clinical trials.

A-336 Comparison Between the Immune Profile of Pregnant and Postpartum Women with and without COVID-19 by Flow Cytometry

Abstract Background The impacts caused by COVID-19 on pregnant and postpartum women are not well characterized yet. It is well known that, due to pregnancy, the maternal organism undergoes immunological adaptations, which may increase the risk of complications of viral diseases. These adaptations, in addition to the inflammatory disorder caused by the SARS-Cov-2, may contribute to severe outcomes as a result of COVID-19 infection. In this study the peripheral levels of total T lymphocytes, CD4+ T lymphocytes, CD8+ T lymphocytes, B lymphocytes and natural killer cells in pregnant and postpartum women with positive and negative PCR for SARS-CoV-2 were determined. Methods A cross-sectional study was performed using peripheral blood samples from pregnant and postpartum women who underwent PCR for the diagnosis of COVID-19 between May 2021 and March 2022. Samples were collected in a public maternity hospital in Northeast of Brazil right on admission for delivery as well as in the immediate puerperium. Blood was collected in tubes containing EDTA for flow cytometry, using the activated cell fluorescence analyzer (FACScan) and the Cell Quest software. The total of T lymphocyte subsets (CD3+), CD3+/CD4+ (ThL) and CD3+/CD8+ (TcL) was determined according to published protocols. B lymphocytes were identified by expression of CD19 (CD19+) and NK and NKT cells were identified by the CD16+/56+ and CD3+/CD16-56+ phenotype, respectively. Lymphocytes were identified by high CD45 expression and low side scatter using the following 3-color monoclonal antibody combinations: fluorescein isothiocyanate (FITC), phycoerythrin (PE) and chlorophyll pyridine protein (PerCP). Results A total of 99 women with a mean age 29 (± 7) years old were used in this study, of which 31 (31.3%) were pregnant and 68 (69.4%) were postpartum women. The diagnosis of COVID-19 was confirmed by PCR in 78 (78.8%) of the participants and in 21 (21.2%) it was discarded after negative PCR. Pregnant and postpartum women infected with SARS-CoV-2 had higher levels of cytotoxic T cells, median (ME) = 574.2; interquartile range (IIQ) = 382.4, when compared with uninfected patients, ME = 404.7; IIQ = 363.5); P = 0.032. Pregnant women with COVID-19 had a lower mean CD3+ count (1351.1 ± 337.7) compared to postpartum women with the disease (1605.6 ± 538.6); t (53.6) = −2.45, P = 0.009. Likewise, lower CD16+/56+ (113.3; IIQ = 172.0) and CD3+/CD16-56+ (52.1; IQ = 53.4) medians were found in pregnant women with COVID-19, when compared with the group of postpartum women without infection (191.2; IIQ = 192.5); U = 396.0, P = 0.043 and (70.8; IIQ = 91.6); U = 376.5, P = 0.025, respectively. Conclusion Pregnant and postpartum women with COVID-19 had significantly higher levels of cytotoxic T cells in peripheral blood. These results may be useful to understand what the SARS-CoV-2 infection causes in the immune system of pregnant and postpartum women. On the other hand, observational studies with larger samples and bias control are required.

124I-labeled anti-CD147 antibody for noninvasive detection of CD147-positive pan-cancers: construction and preclinical studies.

Extracellular matrix metalloproteinase inducer CD147 is a glycoprotein on the cell surface. There is minimal expression of CD147 in normal epithelial and fetal tissues, but it is highly expressed in a number of aggressive tumors. CD147 has been implicated in pan-cancer immunity and progression. With the development of CD147-targeting therapeutic strategy, accurate detection of CD147 expression in tumors and its changes during the therapy is necessary. In this study we constructed a novel radiotracer by labeling the anti-CD147 mAb with radionuclide 124/125I (124/125I-anti-CD147) for noninvasive detection of CD147 expression in pan-cancers, and characterized its physicochemical properties, affinity, metabolic characteristics, biodistribution and immunoPET imaging with 124I-IgG and 18F-FDG as controls. By examining the expression of CD147 in cancer cell lines, we found high CD147 expression in colon cancer cells LS174T, FADU human pharyngeal squamous cancer cells and 22RV1 human prostate cancer cells, and low expression of CD147 in human pancreatic cancer cells ASPC1 and human gastric cancer cells BGC823. 124/125I-anti-CD147 was prepared using N-bromine succinimide (NBS) as oxidant and purified by PD-10 column. Its radiochemical purity (RCP) was over 99% and maintained over 85% in saline or 5% human serum albumin (HSA) for more than 7 d; the RCP of 125I-anti-CD147 in blood was over 90% at 3 h post injection (p.i.) in healthy mice. The Kd value of 125I-anti-CD147 to CD147 protein was 6.344 nM, while that of 125I-IgG was over 100 nM. 125I-anti-CD147 showed much greater uptake in CD147 high-expression cancer cells compared to CD147 low-expression cancer cells. After intravenous injection in healthy mice, 125I-anti-CD147 showed high initial uptake in blood pool and liver, the uptake was decreased with time. The biological half-life of distribution and clearance phases in healthy mice were 0.63 h and 19.60 h, respectively. The effective dose of 124I-anti-CD147 was estimated as 0.104 mSv/MBq. We conducted immunoPET imaging in tumor-bearing mice, and demonstrated a significantly higher tumor-to-muscle ratio of 124I-anti-CD147 compared to that of 124I-IgG and 18F-FDG in CD147 (+) tumors. The expression levels of CD147 in cells and tumors were positively correlated with the maximum standardized uptake value (SUVmax) (P < 0.01). In conclusion, 124/125I-anti-CD147 displays high affinity to CD147, and represents potential for the imaging of CD147-positive tumors. The development of 124I-anti-CD147 may provide new insights into the regulation of tumor microenvironment and formulation of precision diagnosis and treatment programs for tumors.

B7-H3 and CD47 co-expression in gastric cancer is a predictor of poor prognosis and potential targets for future dual-targeting immunotherapy.

Gastric cancer (GC) is one of the most prevalent types of cancer worldwide. B7-H3, an immune checkpoint molecule with promising potential, has been found to be overexpressed in various cancers. CD47 is an anti-phagocytic molecule that interacts with the signal regulatory protein alpha (SIRPα) to affect phagocytes. The relationship between the expression of B7-H3 and CD47, two potential therapeutic targets found in tumor cells, remains unknown. In this study, our objective is to investigate the clinical significance of co-expression of B7-H3 and CD47, as well as the potential therapeutic value of combination therapy in GC. We utilized immunohistochemistry (IHC) to assess the expression of B7-H3, CD47, CD68, CD86 and CD163 in tissue microarrays obtained from 268 GC patients who underwent surgeries. Western blotting was employed to assess the protein level of B7-H3 and CD47 in GC tissues. The co-localization of B7-H3/CD47 and CD68 in GC tissues was determined using multiplex immunohistochemistry (m-IHC). We further verified the relationship between B7-H3/CD47 and macrophage infiltration via flow cytometry. To estimate the clinical outcomes of patients from different subgroups, we employed the Kaplan-Meier curve and the Cox model. Among the 268 GC cases, a total of 180 cases exhibited positive expression of B7-H3, while 122 cases showed positive expression of CD47. In fresh GC clinical tissues, B7-H3 and CD47 protein level was also higher in tumor tissue than in adjacent normal tissue. Remarkably, 91 cases demonstrated co-expression of B7-H3 and CD47. We observed a significant correlation between B7-H3 expression and tumor stage (P = 0.001), differentiation (P = 0.045), and depth (P = 0.003). Additionally, there was a significant association between B7-H3 and CD47 expression (P = 0.018). The percentage of B7-H3 and CD47 double positive cells in fresh GC tumor tissues were elevated compared with control adjacent tissues regardless of CD45- or CD45+ cells (P = 0.0029, P = 0.0012). Patients with high B7-H3 or CD47 expression had significantly lower overall survival (OS) rates compared to those with low expression levels (P = 0.0176 or P = 0.0042). Surprisingly, patients with combined high expression of B7-H3 and CD47 exhibited a considerably worse prognosis than others (P = 0.0007). Univariate analysis revealed that cases with high expression of B7-H3, CD47, or both had significantly higher hazard ratios (HR) than cases with low expression of these markers. Furthermore, the results of multivariate analysis indicated that B7-H3/CD47 co-expression and CD47 expression alone are independent prognostic factors for overall survival. Moreover, significant correlations were observed between B7-H3 and CD68 expression, CD47 and CD68 expression, as well as B7-H3/CD47 co-expression and CD68 expression in GC patients (P < 0.001, P = 0.003, and P < 0.001). Flow cytometry test showed that the percentage of CD68-positive cells but not CD86-positive cells among B7-H3-positive or CD47-positive immune cells in GC tumor tissue was elevated significantly compared with adjacent tissue. Our findings demonstrated a correlation between B7-H3 expression and CD47 expression in GC patient tissues. Co-expression of B7-H3 and CD47 can serve as an indicator of poor prognosis in GC patients. In GC tumor tissue, but not adjacent tissue, B7-H3 and CD47 expression was accompanied with macrophage infiltration.

Thrombin receptor PAR1 silencing in endothelial colony–forming cells modifies stemness and vasculogenic properties

BackgroundThe involvement of thrombin receptor PAR1 in blood vessel development has been largely demonstrated in knockout mice; however, its implication in adult mouse angiogenesis seems very moderate. ObjectivesWe aimed to explore the potential relationships between PAR1, stemness, and angiogenic properties of human endothelial colony–forming cells (ECFCs). Methods and ResultsPAR1 activation on ECFCs using the selective PAR1-activating peptide induced a significant decrease in CD133 expression (RTQ-PCR analysis). In line, silencing of PAR1 gene expression with siRNA increased CD133 mRNA as well as intracellular CD133 protein expression. To confirm the link between CD133 and PAR1, we explored the association between PAR1 and CD133 levels in fast and slow fibroblasts prone to reprogramming. An imbalance between PAR1 and CD133 levels was evidenced, with a decreased expression of PAR1 in fast reprogramming fibroblasts expressing a high CD133 level. Regarding in vitro ECFC angiogenic properties, PAR1 silencing with specific siRNA induced cell proliferation evidenced by the overexpression of Ki67. However, it did not impact migration properties nor ECFC adhesion on smooth muscle cells or human arterial endothelial cells. In a mouse model of hind-limb ischemia, PAR1 silencing in ECFCs significantly increased postischemic revascularization compared to siCtrl-ECFCs along with a significant increase in cutaneous blood flows (P < .0001), microvessel density (P = .02), myofiber regeneration (P < .0001), and human endothelial cell incorporation in muscle (P < .0001). ConclusionIn conclusion, our work describes for the first time a link between PAR1, stemness, and vasculogenesis in human ECFCs.