Evaluation of immune-checkpoint molecules in dMMR/pMMR colorectal cancer by multiplex immunohistochemistry.

PURPOSE: Colorectal cancer is the most common malignancy worldwide. A number of pathological and molecular genetic criteria are currently used as predictors of the disease. They include assessment of MMR deficiency or MSI/MSS status, which among others, determine the immunogenicity of the tumor. In this regard, the evaluation of PD-L1, CTLA-4, and LAG-3 immune checkpoint molecules in different tumor compartments according to MMR status deserves special attention. METHODS: Multiplex immunohistochemistry was used to evaluate the expression of immune checkpoint molecules in the tumor core and at the invasive margin. RESULTS: Data analysis showed the predominance of PD-L1 (p = 0.011), CTLA-4 (p = 0.004), and LAG-3 (p = 0.013) expression at the invasive margin of dMMR carcinomas compared to pMMR samples. Quantitative analysis of TILs population in the tumor core and at the invasive margin allowed establishment of the predominance of CD3+ and CD8+ lymphocytes at the invasive margin of dMMR carcinomas. Study of the CD163+ macrophages population in the same tumor compartments revealed the predominance of the studied TAMs in the core and at the invasive margin of dMMR carcinomas and the predominance of CD163+ macrophages with PD-L1-phenotype in the tumor stroma. CONCLUSION: This study revealed a significant predominance of PD-L1, CTLA-4, LAG-3, and CD 3+ ,CD8+ lymphocytes in dMMR colorectal carcinomas. Further research on the immune landscape in different tumor compartments will likely have high prognostic value for CRC patients, as it might expand the criteria for prescribing immunotherapy.

Efficacy and safety of camrelizumab combined with chemotherapy in the treatment of advanced biliary malignancy and associations between peripheral blood lymphocyte subsets and clinical outcomes.

BACKGROUND: Biliary tract cancer (BTC) is a highly heterogeneous aggressive tumor, and advanced patients have poor prognosis. This work aimed to evaluate the efficacy and safety of camrelizumab combined with chemotherapy in treating advanced BTC, and to explore predictive biomarkers for distinguishing effective population. METHODS: 183 advanced BTC patients admitted from September 2018 to September 2021 were retrospectively selected. 93 patients were treated with camrelizumab combined with chemotherapy (C+C group) and 90 patients were treated with chemotherapy alone (C group). Objective response rate (ORR), disease control rate (DCR), median progression-free survival (mPFS), and median overall survival (mOS) were analyzed between two groups. Peripheral blood lymphocyte subsets were assessed by flow cytometry pre- and post-treatment. RESULTS: The mPFS (6.9 months) and mOS (12.1 months) in the C+C group were significantly longer than those in the C group, which were 5.2 months and 9.8 months respectively (HR 0.46, 95% CI 0.38-0.54, p=0.017; HR 0.39, 95% CI 0.32-0.47, p=0.033). The percentage of Total T, CD4+T, natural killer (NK) cells, lymphocyte, and CD4+/CD8+ cell ratios were significantly increased in effective patients after C+C treatment, but didn't increase in progressive disease (PD) patients. Higher percentage of Total T, CD4+T, and higher CD4+/CD8+ cell ratios post-treatment were associated with longer OS. CONCLUSIONS: Camrelizumab combining chemotherapy significantly prolonged the mPFS and mOS of advanced BTC patients. Immunotherapy may improve the immune status of advanced patients, and immunotherapy efficacy might be predicted based on the peripheral blood lymphocyte subsets.

Prognostic impact of nectin-like molecule-5 (CD155) expression in non-small cell lung cancer.

BACKGROUND: CD155 is a transmembrane protein that inhibits antitumor immune response and represents a predictor of worse prognosis in non-small-cell lung cancer (NSCLC). However, it remains unexplored its association with clinical characteristics and genomic status of Latin American patients. This study characterizes the CD155 expression and its clinical implications in this population. METHODS: Tissue biopsies from 86 patients with locally-advanced or metastatic NSCLC were assessed for CD155 protein expression, ALK rearrangements and EGFR mutations. Cutoff values for high CD155 expression (CD155high) were determined from receiver operating characteristic (ROC) curves according to 2-year survival. It was evaluated its association with clinicopathological features, median progression-free survival (mPFS) and overall survival (mOS). RESULTS: the cutoff score for CD155high was 155 in the entire cohort and in patients without oncogenic alterations, and it was 110 in patients with oncogenic alterations. Eighty-four patients (97.7%) were CD155 positive, of which fifty-six (65.0%) had CD155high. EGFR L858R mutation related to lower CD155 IHC score than exon 19 deletion. Individuals with CD155high showed a shorter mOS (13.0 vs. 30.8 months; HR: 1.96 [95% CI, 1.15-3.35]; p = 0.014). Patients without oncogenic alterations having a CD155high displayed shorter mPFS (1.6 vs. 6.4 months, HR: 2.09 [95% CI, 1.06-4.20]; p = 0.034) and mOS (2.9 vs. 23.1 months; HR: 1.27 [95% CI, 1.07- 4.42]; p = 0.032). Patients with oncogenic alterations having CD155high only showed a trend to shorter mOS (26.3 vs. 52.0 months; HR: 2.39 [95% CI, 0.98-5.83]; p = 0.058). CONCLUSION: CD155high is a predictor of worse outcomes in patients with advanced NSCLC, predominantly among those without oncogenic alterations. CD155 could be a potential biomarker and a molecular target in patients with poor responses to current therapies.

New Advances in the Study of CMTM6, a Focus on Its Novel Non-Canonical Cellular Locations, and Functions beyond Its Role as a PD-L1 Stabilizer.

CMTM6 is a membrane protein that acts as a regulator of PD-L1, maintaining its expression on the cell surface, and can prevent its lysosome-mediated degradation. It is unknown if CMTM6 is present in the plasma of patients with cervical cancer, and if it has non-canonical subcellular localizations in cell lines derived from cervical cancer. Our objective was to determine whether CMTM6 is found in plasma derived from cervical cancer patients and its subcellular localization in cell lines. Patient plasma was separated into exosome-enriched, exosome-free, and total plasma fractions. The levels of CMTM6 in each fraction were determined using ELISA and Western blot. Finally, for the cellular model, HeLa, SiHa, CaSki, and HaCaT were used; the subcellular locations of CMTM6 were determined using immunofluorescence and flow cytometry. Soluble CMTM6 was found to be elevated in plasma from patients with cervical cancer, with a nearly three-fold increase in patients (966.27 pg/mL in patients vs. 363.54 pg/mL in controls). CMTM6 was preferentially, but not exclusively, found in the exosome-enriched plasma fraction, and was positively correlated with exosomal PD-L1; CMTM6 was identified in the membrane, intracellular compartments, and culture supernatant of the cell lines. These results highlight that CMTM6, in its various presentations, may play an important role in the biology of tumor cells and in immune system evasion.

Correlation of PD-L1 expression with different clinico-pathological and immunohistochemical features of ovarian surface epithelial tumors.

BACKGROUND: Primary carcinoma of the ovary (OCs) are responsible for a significant number of deaths related to cancer, and have the highest rate of death related to cancers of the female reproductive organs. Programmed cell death 1 (PD1) protein, acts as an immune checkpoint, and has an important role in the down-regulation of the immune system by preventing the activation of T-cells, which will weaken the autoimmunity and increases self-tolerance. This study aimed at the evaluation of the immunohistochemical (IHC) expression of PD-L1 in various primary surface ovarian epithelial tumours and to test its correlation with different clinicopathological parameters together with the expression of a panel of P53, ER and PR. METHODS: A set of 102 cases of primary ovarian surface epithelial neoplasms (benign, borderline and malignant) were collected to construct Tissue Microarray (TMA) using 3 tissue cores from each case. IHC for PD-L1, p53, PR and ER was performed. The expression of PD-L1 was evaluated in relation to some clinicopathological parameters and to the expression patterns of other markers. RESULTS: Expression of PD-L1 was detected in about 51% (n = 36) of malignant tumours. The malignant group significantly showed PD-L1 positivity compared to borderline and benign groups. The malignant tumours significantly showed PD-L1 and total p53 positivity in comparison to borderline group. Also, malignant tumours significantly showed higher combined positivity of PD-L1 and either PR or ER compared to borderline and benign lesions. No significant correlation was appreciated between PD-L1 expression and with any of the studied clinicopathological parameters. CONCLUSIONS: This study showed a significant PD-L1 expression in malignant primary surface epithelial tumours. Construction of a panel of IHC markers, including PD-L1, could have a potential value to define patients those would benefit from the addition of immunotherapy to the treatment plan.

Light exposure of tetra-cationic porphyrins containing peripheral Pd(II)-bipyridyl complexes and the induced effects on purified DNA molecule, fibroblast and melanoma cell lines.

Photodynamic therapy (PDT) combines a light source, oxygen, and a photosensitizer (PS) to generate reactive oxygen species (ROS) for treating diseases. In this study, we evaluated two meso-tetra-pyridyl porphyrins with [Pd(bpy)Cl]+, namely 3-PdTPyP and 4-PdTPyP, as PS for PDT application. DNA interaction was assessed by spectroscopic measurements (UV-Vis and fluorescence emission), viscosity analysis, and molecular docking simulations. The results indicate that Pd(II)-porphyrins do not intercalate into DNA, suggesting that the minor groove is the primary interaction site, mainly through van der Waals forces. These metalloporphyrins effectively induced nitrogenous bases oxidation, particularly in purines, after white light irradiation. The induced DNA lesions were able to inactivate plasmid DNA metabolism (DNA replication and transcription) in a bacterial model. 3-PdTPyP and 4-PdTPyP significantly decreased the viability of treated melanoma cell lines (A375 and B16-F10), demonstrating that melanoma cell lines were more sensitive to these Pd(II)-porphyrins than the fibroblast cell line (L929). Moreover, 3-PdTPyP was more photototoxic to A375 cells (IC50 = 0.43 µM), whereas 4-PdTPyP was more photototoxic to B16-F10 cells (IC50 = 0.51 µM). These findings suggest that these porphyrins are promising PS for future PDT research focused on skin cancer.

Uncovering the Expression Pattern of the Costimulatory Receptors ICOS, 4-1BB, and OX-40 in Exhausted Peripheral and Tumor-Infiltrating Natural Killer Cells from Patients with Cervical Cancer.

Cervical cancer (CC) poses a significant health burden, particularly in low- and middle-income countries. NK cells play a crucial role against CC; however, they can become exhausted and lose their cytotoxic capacity. This work explores the expression of costimulatory receptors (ICOS, 4-1BB, OX-40) in exhausted NK cells from CC patients. Peripheral blood and tumor biopsies were collected, and flow cytometry was used to evaluate the expression of costimulatory receptors in exhausted NK cells. There is an increase of peripheral exhausted NK cells (PD-1+TIGIT+) in CC patients; this subpopulation has a selectively increased expression of the costimulatory receptors ICOS and 4-1BB. An exhausted population is also highly increased in tumor-infiltrating NK cells, and it shows a dramatically increased expression of the costimulatory receptors ICOS (>15×) and 4-1BB (>10×) compared to peripheral NK cells. The exhausted cells, both in the periphery and in the tumor infiltrating lymphocytes (TILs), are also more likely than non-exhausted NK cell populations (PD-1-TIGIT-) to express these costimulatory receptors; increases ranging from 2.0× ICOS, 2.4× 4-1BB, and 2.6× OX-40 in CD56dim PBMCs to 1.5× ICOS, 5× 4-1BB, and 10× OX-40 in TILs were found. Our study demonstrates for the first time the increased expression of the costimulatory receptors ICOS, 4-1BB, and OX-40 in peripheral CD56dim, CD56bright, and tumor-infiltrating NK cells in CC. Targeting these receptors for stimulation could reverse exhaustion and be a promising immunotherapy strategy.

PD-L1 expression in non-small cell lung carcinoma in Latin America: a systematic review and meta-analysis.

Background: Programmed cell death ligand 1 (PD-L1) expression in non-small cell lung carcinoma (NSCLC) is a crucial factor in predicting responses to immunotherapy. This systematic review and meta-analysis focuses on the prevalence of PD-L1 expression and clinicopathological features among Hispanic/Latino (H/L) populations. Methods: Embase, LILACS, Medline, and Virtual Health Library were searched for studies that evaluated the prevalence of PD-L1 in H/L patients. The protocol was submitted to PROSPERO with ID CRD42023488547. We employed the Joanna Briggs Institute Checklist for Systematic Reviews and Research Syntheses to assess the methodological quality and applicability of the included studies. Meta-analyses were done to determine the prevalence using a random effects model. Results: The meta-analysis, encompassing 21 articles with 16,486, revealed that 80.2% of patients had PD-L1 expression data available (n=13,222). The prevalence calculated of PD-L1 expression in Latino NSCLC patients was 55% [95% confidence interval (CI): 0.54-0.55], with 31% (95% CI: 0.27-0.36) showing a tumoral proportion score (TPS) of 1-49%, and 23% (95% CI: 0.16-0.30) registering a TPS ≥50%. Higher expression was observed in male gender, smoking, adenocarcinoma subtypes, poor tumor differentiation, and advanced stages. PD-L1 expression was most frequent in EGFR wild-type status (82.5%) with a odds ratio (OR) 1.54 (95% CI: 1.24-1.92) and PD-L1 expression was associated with ALK positive (OR =1.54; 95% CI: 1.24-1.92). Conclusions: This meta-analysis provides a comprehensive overview of PD-L1 expression in NSCLC in the H/L population. The findings underscore the significant prevalence of PD-L1 expression and emphasize the relevance of immunotherapy in this population. Understanding the clinicopathological features associated with PD-L1 expression can contribute to tailored treatment strategies for NSCLC in Latin America.

Correlation between exosomal PD-L1 and prognosis in patients with cancer: a systematic review and meta-analysis.

BACKGROUND: The predictive role of exosomal programmed cell death ligand l (exoPD-L1) in prognosis has been studied extensively; however, there is still no consensus. METHODS: Three databases, including EMBASE, PubMed, and Web of Science, were searched through January 4, 2024. The pooled hazard ratios (HRs) with 95% confidence intervals (95%CIs) were used to identify the relationship between circulating exoPD-L1 and prognosis. RESULTS: 15 studies with 1091 patients with cancer were included in this statistical analysis. High exoPD-L1 level was correlated with shorter progression-free survival (PFS) (HR = 2.58, 95% CI: 1.75-3.81) and overall survival (OS) (HR = 1.61, 95% CI: 1.32-1.98). Meanwhile, we found that dynamic upregulation of circulating exoPD-L1 in the early stages of immunotherapy was a favorable factor for prognosis (PFS: HR = 0.34, 95% CI: 0.23-0.51; OS: HR = 0.21, 95% CI: 0.13-0.26). CONCLUSION: Circulating exoPD-L1 may be a valuable prognostic indicator for patients with cancer and monitoring its changes in the early stages of immunotherapy might be used to predict tumor response and clinical outcome. This conclusion may not apply to superficial tumors.

Persistence of lung structural and functional alterations at one year post-COVID-19 is associated with increased serum PD-L2 levels and altered CD4/CD8 ratio.

BACKGROUND: Persistent respiratory symptoms and lung abnormalities post-COVID-19 are public health problems. This study evaluated biomarkers to stratify high-risk patients to the development or persistence of post-COVID-19 interstitial lung disease. METHODS: One hundred eighteen patients discharged with residual lung abnormalities compatible with interstitial lung disease (COVID-ILD patients) after a severe COVID-19 were followed for 1 year (post-COVID-ILD patients). Physical examination, pulmonary function tests, and chest high-resolution computed tomography (HRCT) were performed. Soluble forms (s) of PD-L1, PD-L2, TIM-3, and GAL-9 were evaluated in serum and cell culture supernatant, as well as T-cells subsets and the transmembrane expression of PD-L1 and PD-L2 on the cell surface. RESULTS: Eighty percent of the post-COVID-ILD patients normalized their lung function at 1-year follow-up, 8% presented COVID-independent ILD, and 12% still showed functional and HRCT alterations. PD-L2 levels were heterogeneous during acute COVID-19 (aCOVID); patients who increased (at least 30%) their sPD-L2 levels at 1 year post-COVID-19 and exhibited altered CD4/CD8 ratio showed persistence of chest tomographic and functional alterations. By contrast, patients who decreased sPD-L2 displayed a complete lung recovery. sPD-L1, sTIM-3, and sGAL-9 increased significantly during aCOVID and decreased in all patients after 1-year follow-up. CONCLUSION: Increased sPD-L2 and an altered CD4/CD8 ratio after 12 months of aCOVID are associated with the persistence of lung lesions, suggesting that they may contribute to lung damage post-COVID-19.

MDSCs use a complex molecular network to suppress T-cell immunity in a pulmonary model of fungal infection.

Background: Paracoccidioidomycosis (PCM) is a systemic endemic fungal disease prevalent in Latin America. Previous studies revealed that host immunity against PCM is tightly regulated by several suppressive mechanisms mediated by tolerogenic plasmacytoid dendritic cells, the enzyme 2,3 indoleamine dioxygenase (IDO-1), regulatory T-cells (Tregs), and through the recruitment and activation of myeloid-derived suppressor cells (MDSCs). We have recently shown that Dectin-1, TLR2, and TLR4 signaling influence the IDO-1-mediated suppression caused by MDSCs. However, the contribution of these receptors in the production of important immunosuppressive molecules used by MDSCs has not yet been explored in pulmonary PCM. Methods: We evaluated the expression of PD-L1, IL-10, as well as nitrotyrosine by MDSCs after anti-Dectin-1, anti-TLR2, and anti-TLR4 antibody treatment followed by P. brasiliensis yeasts challenge in vitro. We also investigated the influence of PD-L1, IL-10, and nitrotyrosine in the suppressive activity of lung-infiltrating MDSCs of C57BL/6-WT, Dectin-1KO, TLR2KO, and TLR4KO mice after in vivo fungal infection. The suppressive activity of MDSCs was evaluated in cocultures of isolated MDSCs with activated T-cells. Results: A reduced expression of IL-10 and nitrotyrosine was observed after in vitro anti-Dectin-1 treatment of MDSCs challenged with fungal cells. This finding was further confirmed in vitro and in vivo by using Dectin-1KO mice. Furthermore, MDSCs derived from Dectin-1KO mice showed a significantly reduced immunosuppressive activity on the proliferation of CD4+ and CD8+ T lymphocytes. Blocking of TLR2 and TLR4 by mAbs and using MDSCs from TLR2KO and TLR4KO mice also reduced the production of suppressive molecules induced by fungal challenge. In vitro, MDSCs from TLR4KO mice presented a reduced suppressive capacity over the proliferation of CD4+ T-cells. Conclusion: We showed that the pathogen recognition receptors (PRRs) Dectin-1, TLR2, and TLR4 contribute to the suppressive activity of MDSCs by inducing the expression of several immunosuppressive molecules such as PD-L1, IL-10, and nitrotyrosine. This is the first demonstration of a complex network of PRRs signaling in the induction of several suppressive molecules by MDSCs and its contribution to the immunosuppressive mechanisms that control immunity and severity of pulmonary PCM.

The influence of PD-L1 expression levels on the efficacy of combination therapy in thymic epithelial tumors.

BACKGROUND: The significant expression of PD-L1 in thymic epithelial tumors (TETs) has been confirmed, and immunotherapy and its combination therapy have been effective in TETs. However, there is no present evidence that the expression levels of PD-L1 affects the efficacy of combination therapy. Our study aimed to shed light on this relationship. METHODS: Patients with thymic epithelial tumors (TETs) from multicenter hospitals were retrospectively identified. Objective response rate (ORR), progression-free survival (PFS), overall survival (OS), and immune-related adverse events (irAEs) in 22 patients were included. We divided the patients the 22 patients with PD-L1 test into three levels (high expression, low expression and no expression) and analyzed the relationship between the levels of PD-L1 expression and the efficacy of combination therapy. RESULTS: Combination therapy showed an effective benefit in 22 patients with TETs, the median PFS (mPFS) was 16 months (95% CI: 8.5-23.5) and the median OS (mOS) was 38 months (95% CI: 21.5-54.5). Cox-regressive analysis found whether PD-L1 expression affected the PFS of patients (p = 0.017). Among the patients with PD-L1 expression, the levels of expression were correlated with curative effect (Kruskal-Wallis test, PFS: P = 0.012; OS: P = 0.01), and high expression group was along with better efficacy than low expression (Wilcoxon test, P = 0.01). Moreover, in 17 patients treated with immunotherapy combined with chemotherapy, the expression of PD-L1 was also associated with efficacy (Kruskal-Wallis test, p = 0.021). CONCLUSIONS: PD-L1 expression affects the PFS of patients. High expression of PD-L1 patients with TETs responded better to combination therapy, which could provide a therapeutic option in clinic. Besides, other targeted treatments should be considered.

Early salvage therapy with anti-PD-1 antibody Camrelizumab in patients with advanced cervical cancer: a retrospective study.

OBJECTIVE: To observe the clinical efficacy of Camrelizumab in patients with advanced cervical cancer who presented with resistance to initial therapy. METHODS: We retrieved data from 25 patients with advanced (stage IIA2-IV) cervical cancer who were administered a combination salvage therapy with Camrelizumab due to the poor response to initial chemotherapy. The primary outcome was objective response rate (ORR) and disease control rate (DCR), the secondary endpoints included progression-free survival (PFS) and the occurrence of adverse events. To evaluate its long-term effect on PFS, we included 64 patients diagnosed with stage IIA2-IV during the study period, who were responsive to initial radiotherapy or chemotherapy and received conventional therapy as control. RESULTS: Camrelizumab exhibits a high salvage treatment efficacy, with ORR of 80.0% (20/25) and DCR of 88.0% (22/25) in Camrelizumab salvage group (CS group). The PFS in CS group was significantly longer than that in control group. The median follow-up time were 18.1 and 18.3 months in the CS group and the control group, respectively, and neither achieved median PFS. The adverse event (AEs) rates in the CS and control groups were 52.0% (13/25) and 51.6% (33/64), in which the most common adverse events were myelosuppression, cutaneous capillary endothelial proliferation (CCEP), and elevated liver enzymes, and the grade of AEs was less than grade 3 in all patients. CONCLUSION: Camrelizumab demonstrated promising efficacy and safety as the early salvage treatment for patients with advanced cervical cancer.

Exploring the Role of PD-1 in the Autoimmune Response: Insights into Its Implication in Systemic Lupus Erythematosus.

Despite advances in understanding systemic lupus erythematosus (SLE), many challenges remain in unraveling the precise mechanisms behind the disease's development and progression. Recent evidence has questioned the role of programmed cell death protein 1 (PD-1) in suppressing autoreactive CD4+ T cells during autoimmune responses. Research has investigated the potential impacts of PD-1 on various CD4+ T-cell subpopulations, including T follicular helper (Tfh) cells, circulating Tfh (cTfh) cells, and T peripheral helper (Tph) cells, all of which exhibit substantial PD-1 expression and are closely related to several autoimmune disorders, including SLE. This review highlights the complex role of PD-1 in autoimmunity and emphasizes the imperative for further research to elucidate its functions during autoreactive T-cell responses. Additionally, we address the potential of PD-1 and its ligands as possible therapeutic targets in SLE.

Analysis of PD-1/PD-L1 variations in lung cancer and association with immunotherapeutic efficacy and prognosis: A nonrandomized controlled trial.

INTRODUCTION: This study aims to explore Programmed Death Receptor-1 (PD-1) and Programmed Death Ligand-1 (PD-L1) variations in Lung Cancer (LC) tissues and Peripheral Blood (PPB) and their association with immunotherapy efficacy and prognosis. METHOD: 72 patients with LC were included in the LC group and 39 patients with concurrent benign lung disease were included in the benign group. PD-1/PDL-1 was compared in PPB and lung tissue. All LC patients were treated with immunotherapy. The relationship between PD-1/PDL-1 in LC tissue and PPB and immunotherapy efficacy was analyzed. Patients were divided into death and survival groups, and PD-1/PDL-1 in tumor tissues and PPB were compared. RESULTS: The authors found that PD-1 and PDL-1 positive expression in lung tissue and PPB in LC patients was elevated. Combined detection of PD-1 and PDL-1 was effective in diagnosing LC and evaluating the prognosis of LC patients. PD-1 and PDL-1 positive expression was reduced after disease remission while elevated in dead patients. The 3-year survival rate of patients with PD-1 positive expression was 45.45 % (25/55), which was lower (82.35 %, 14/17) than those with PD-1 negative expression. The 3-year survival rate of patients with positive and negative expression of PDL-1 was 48.78 % (20/41) and 61.29 % (19/31), respectively. DISCUSSION: The present results demonstrated that PD-1 and PDL-1 are abnormal in cancer tissue and PPB of LC patients. The combined detection of PD-1 and PDL-1 has diagnostic value for LC and evaluation value for the efficacy and prognosis of immunotherapy.

Development of methodology for the visual identification of Tributyltin (TBT) in antifouling paint matrices.

Organotin compounds (OTC), mainly tributyltin (TBT), have been used since the 1970s as biocides in the composition of antifouling paints. Due to its physical-chemical characteristics, TBT has high toxicity to the marine environment affecting non-target organisms. The present study aims to develop a method of direct visual identification of TBT in antifouling paints using the cyclopalladate complex, 4- (2-thiazolylazo) resorcinol (TAR-Pd), synthesized in our laboratory. Tests were performed in blank and in the paint matrix with the following OTC: TBT-O; TBT-Cl; TPT-Cl; DBT-Cl (tributyltin oxide, tributyltin chloride, triphenyltin chloride, dibutyltin chloride), in addition to the SnCl4 and SnCl2 compounds (tin IV chloride and tin II chloride), all at a concentration of approximately 20 g/ kg of dry paint). The test was performed by applying paint samples to test bodies and scraping a few tens of milligrams of the dry paint film. The scraped paint samples were submitted to the test, showing a different staining reaction for the TBT-Cl and SnCl4 samples concerning blank and other samples (TBT-O, TPT, DBT-Cl, and SnCl2). Solution tests were performed to characterize reaction products by spectroscopy in the visible band. The method developed has potential for application in real samples, being selective for TBT-Cl and SnCl4 in an acid medium, obtaining a limit of detection, in the range of 1-10 mg/kg dry paint.

Evaluación de la expresión de PD-L1 e infiltración linfocitaria intratumoral en carcinoma de mama invasivo triple negativo / Evaluation of PD-L1 expression and intratumoral lym phocytic infiltration in triple-negative invasive breast car cinoma

Resumen Introducción : El endofenotipo de cáncer de mama triple negativo (TNBC) es uno de los menos frecuentes y sin diana terapéutica, por tanto, se plantea estudiar la correlación del punto de control inmunológico PD-L1 con el establecimiento de microambiente tumoral evaluado por la infiltración linfocitaria intratumoral estromal (TILs) y su importancia en la práctica clínica. Métodos : Se realizó un estudio retrospectivo de casos y controles, con 31 casos de carcinoma infiltrante de la mama triple negativo y 57 controles no pareados de endofenotipo Luminal A, Luminal B y HER-2 atendidos en un año. Se evaluaron las variables: tipo y grado his tológico, expresión PD-L1 con el clon 22C3, TILs, invasión linfovascular, tamaño tumoral, compromiso de ganglios linfáticos y metástasis. El análisis estadístico se ejecutó con la prueba de chi cuadrado y prueba de coeficiente de correlación de Spearman. Resultados : Se encontró una correlación negativa estadísticamente significativa entre TILs y PD-L1 (rho - 0.106, p 0.025), indicando que a mayor expresión de PD-L1, es menor la infiltración linfocitaria intratumo ral. En los grupos de TILs B (10-40% TILs) y C (40-90% TILs) donde se presenta marcado infiltrado inflamatorio intratumoral se evidenció mayor número de pacientes negativos para PD-L1 (CPS <10) con 16 y 10 casos res pectivamente. Para los casos TNBC se logró identificar un coeficiente de asociación negativa (rho -0.378) y con significancia estadística (p 0.01). Discusión : Se estableció la asociación de TNBC, TILs y expresión de PDL1, lo cual es importante para la instau ración de terapias diana y el desarrollo de la medicina de precisión.

Abstract Introduction : Triple negative breast cancer endophe notype (TNBC) is one of the least frequent and without therapeutic target; therefore we propose to study the correlation of PD-L1 immune checkpoint with the es tablishment of tumor microenvironment assessed by intratumoral stromal lymphocyte infiltration (TILS) and its importance in clinical practice. Methods : A retrospective case-control study was performed, with 31 cases of triple-negative infiltrat ing breast carcinoma and 57 unmatched controls of Luminal A, Luminal B and HER-2 endophenotype seen in one year. The following variables were evaluated: histologic type and grade, PD-L1 expression with clone 22C3, TILS, lymphovascular invasion, tumor size, lymph node involvement and metastasis. Statistical analysis was performed with the chi-square test and Spearman correlation coefficient test. Results : a statistically significant negative correlation was found between TILS and PD-L1 (rho - 0.106, p 0.025), indicating that the higher the expression of PD-L1, the lower the intratumoral lymphocytic infiltration. In the TILS B (10-40% TILS) and C (40-90% TILS) groups where there was a marked intratumoral inflammatory infiltrate, a greater number of patients were negative for PD-L1 (CPS <10) with 16 and 10 cases, respectively. For TNBC cases a negative association coefficient was identified (rho -0.378) with statistical significance (p 0.01). Discussion : The association between TNBC, TILS and PDL1 expression was established, which is important for the establishment of target therapies and the develop ment of precision medicine.

Profiling of Tumor-Infiltrating Immune Cells and Their Impact on Survival in Glioblastoma Patients Undergoing Immunotherapy with Dendritic Cells.

Glioblastomas (GBM) are the most common primary malignant brain tumors, comprising 2% of all cancers in adults. Their location and cellular and molecular heterogeneity, along with their highly infiltrative nature, make their treatment challenging. Recently, our research group reported promising results from a prospective phase II clinical trial involving allogeneic vaccination with dendritic cells (DCs). To date, six out of the thirty-seven reported cases remain alive without tumor recurrence. In this study, we focused on the characterization of infiltrating immune cells observed at the time of surgical resection. An analytical model employing a neural network-based predictive algorithm was used to ascertain the potential prognostic implications of immunological variables on patients' overall survival. Counterintuitively, immune phenotyping of tumor-associated macrophages (TAMs) has revealed the extracellular marker PD-L1 to be a positive predictor of overall survival. In contrast, the elevated expression of CD86 within this cellular subset emerged as a negative prognostic indicator. Fundamentally, the neural network algorithm outlined here allows a prediction of the responsiveness of patients undergoing dendritic cell vaccination in terms of overall survival based on clinical parameters and the profile of infiltrated TAMs observed at the time of tumor excision.

Effects of Apatinib combined with Temozolomide on levels of sPD-1 and sPD-L1 in patients with drug-resistant recurrent glioblastoma.

OBJECTIVE: This study aimed to explore the effects of Apatinib combined with Temozolomide (TMZ) on the levels of Soluble PD-1 (sPD-1) and Soluble Programmed Death-1 Ligand (sPD-L1) in patients with drug-resistant recurrent Glioblastoma (GB). STUDY DESIGN: A total of 69 patients with recurrent GB from September 2020 to March 2022 were recruited and assigned to the control group (n = 34) and observation group (n = 35) according to different treatment options after tumor recurrence. The control group was treated with TMZ, and the observation group was treated with Apatinib combined with TMZ. Levels of sPD-1 and spd-l1, clinical efficacy, survival time and adverse reactions were observed and compared between the two groups. RESULTS: General data including gender, age, body mass index, and combined diseases indicated no statistical significance between groups (p > 0.05). Before the intervention, sPD-1 and sPD-L1 levels were not significantly different in the two groups (p > 0.05). After interventions, levels of PD-1 and sPD-L1 levels decreased significantly (p < 0.05). The objective remission rate and clinical benefit rate of the observation group were higher and overall survival and progression-free survival were longer than those of the control group (p < 0.05). No significant difference was observed in major adverse reactions among patients (p > 0.05). CONCLUSIONS: Apatinib combined with TMZ is safe and effective in the treatment of recurrent GB. The combined application of the two can reduce the levels of sPD-1 and sPD-L1, which has important clinical application value.

Porphyromonas gingivalis, a bridge between oral health and immune evasion in gastric cancer.

Porphyromonas gingivalis (P. gingivalis) is a gram-negative oral pathogen associated with chronic periodontitis. Previous studies have linked poor oral health and periodontitis with oral cancer. Severe cases of periodontal disease can result in advanced periodontitis, leading to tissue degradation, tooth loss, and may also correlate with higher gastric cancer (GC) risk. In fact, tooth loss is associated with an elevated risk of cancer. However, the clinical evidence for this association remains inconclusive. Periodontitis is also characterized by chronic inflammation and upregulation of members of the Programmed Death 1/PD1 Ligand 1 (PD1/PDL1) axis that leads to an immunosuppressive state. Given that chronic inflammation and immunosuppression are conditions that facilitate cancer progression and carcinogenesis, we hypothesize that oral P. gingivalis and/or its virulence factors serve as a mechanistic link between oral health and gastric carcinogenesis/GC progression. We also discuss the potential impact of P. gingivalis' virulence factors (gingipains, lipopolysaccharide (LPS), and fimbriae) on inflammation and the response to immune checkpoint inhibitors in GC which are part of the current standard of care for advanced stage patients.