Discovery of YS-1 as a cell line of gastric inflammatory cancer-associated fibroblasts.

BACKGROUND: Inflammatory cancer-associated fibroblasts (iCAFs) was first identified by co-culture of pancreatic stellate cells and tumor organoids. The key feature of iCAFs is IL-6high/αSMAlow. We examine this phenomenon in gastric cancer using two cell lines of gastric fibroblasts (HGF and YS-1). METHODS AND RESULTS: HGF or YS-1 were co-cultured with MKN7 (a gastric adenocarcinoma cell line) in Matrigel. IL-6 protein levels in the culture supernatant were measured by ELISA. The increased production of IL-6 was not observed in any of the combinations. Instead, the supernatant of YS-1 exhibited the higher levels of IL-6. YS-1 showed IL-6high/αSMA (ACTA2)low in real-time PCR, mRNA-seq and immunohistochemistry. In mRNA-seq, iCAFs-associated genes and signaling pathways were up-regulated in YS-1. No transition to myofibroblastic phenotype was observed by monolayer culture, or the exposure to sonic hedgehog (SHH) or TGF-ß. YS-1 conditioned medium induced changes of morphology and stem-ness/differentiation in NUGC-3 (a human gastric adenocarcinoma cell line) and UBE6T-15 (a human bone marrow-derived mesenchymal stem cell line). CONCLUSIONS: YS-1 is a stable cell line of gastric iCAFs. This discovery will promote further research on iCAFs for many researchers.

Germline homozygosity and allelic imbalance of HLA-I are common in esophagogastric adenocarcinoma and impair the repertoire of immunogenic peptides.

BACKGROUND: The individual HLA-I genotype is associated with cancer, autoimmune diseases and infections. This study elucidates the role of germline homozygosity or allelic imbalance of HLA-I loci in esophago-gastric adenocarcinoma (EGA) and determines the resulting repertoires of potentially immunogenic peptides. METHODS: HLA genotypes and sequences of either (1) 10 relevant tumor-associated antigens (TAAs) or (2) patient-specific mutation-associated neoantigens (MANAs) were used to predict good-affinity binders using an in silico approach for MHC-binding (www.iedb.org). Imbalanced or lost expression of HLA-I-A/B/C alleles was analyzed by transcriptome sequencing. FluoroSpot assays and TCR sequencing were used to determine peptide-specific T-cell responses. RESULTS: We show that germline homozygosity of HLA-I genes is significantly enriched in EGA patients (n=80) compared with an HLA-matched reference cohort (n=7605). Whereas the overall mutational burden is similar, the repertoire of potentially immunogenic peptides derived from TAAs and MANAs was lower in homozygous patients. Promiscuity of peptides binding to different HLA-I molecules was low for most TAAs and MANAs and in silico modeling of the homozygous to a heterozygous HLA genotype revealed normalized peptide repertoires. Transcriptome sequencing showed imbalanced expression of HLA-I alleles in 75% of heterozygous patients. Out of these, 33% showed complete loss of heterozygosity, whereas 66% had altered expression of only one or two HLA-I molecules. In a FluoroSpot assay, we determined that peptide-specific T-cell responses against NY-ESO-1 are derived from multiple peptides, which often exclusively bind only one HLA-I allele. CONCLUSION: The high frequency of germline homozygosity in EGA patients suggests reduced cancer immunosurveillance leading to an increased cancer risk. Therapeutic targeting of allelic imbalance of HLA-I molecules should be considered in EGA.

Comparison of programmed death-ligand 1 expression in adenocarcinoma and squamous cell carcinoma of the cervix in paraffin blocks of patients with cervical cancer.

AIMS: Cervical cancer (CC) is a common malignancy in women, predominantly caused by human papillomavirus. The most subtypes are adenocarcinomas (AC) and squamous cell carcinomas (SCC), which show various features and treatment responses. Programmed death-ligand 1 (PD-L1) and programmed cell death protein 1 (PD-1) as Immune checkpoint molecules, play a role in immune evasion. We investigated PD-L1 expression in AC and SCC of the cervix and explored its link to clinical characteristics. METHODS AND RESULTS: The present cross-sectional research was done between 2016 and 2022 on samples in Shahid Beheshti University of Medical Sciences-affiliated hospitals in Iran. Histological tissue samples of CCs (16 AC and 48 SCC) were assessed, and clinical information was obtained by reviewing their medical documents. PD-L1 expression was evaluated by immunohistochemistry and we used the combined positive score. SCC cases showed a higher (not significant) PD-L1 expression. The PD-L1 expression and clinical characteristics were not significantly correlated in both subgroups. CONCLUSION: Although SCC cases exhibited higher PD-L1 expression, this difference was non-significant. More investigations should highlight the role of PD-L1 in CC and the potential benefits of immunotherapy.

Induction of autophagy-dependent and caspase- and microtubule-acetylation-independent cell death by phytochemical-stabilized gold nanopolygons in colorectal adenocarcinoma cells.

Collective functionalization of the phytochemicals of medicinal herbs on nanoparticles is emerging as a potential cancer therapeutic strategy. This study presents the facile synthesis of surface-functionalized gold nanoparticles using Bacopa monnieri (Brahmi; Bm) phytochemicals and their therapeutically relevant mechanism of action in the colorectal cancer cell line, HT29. The nanoparticles were characterized using UV-visible spectroscopy, TEM-EDAX, zeta potential analysis, TGA, FTIR and 1H NMR spectroscopy, and HR-LC-MS. The particles (Bm-GNPs) were of polygonal shape and were stable against aggregation. They entered the target cells and inhibited the viability and clonogenicity of the cells with eight times more antiproliferative efficacy (25 ± 1.5 µg mL-1) than Bm extract (Bm-EX). In vitro studies revealed that Bm-GNPs bind tubulin (a protein crucial in cell division and a target of anticancer drugs) and disrupt its helical structure without grossly altering its tertiary conformation. Like other antitubulin agents, Bm-GNPs induced G2/M arrest and ultimately killed the cells, as confirmed using flow cytometry analyses. ZVAD-FMK-mediated global pan-caspase inhibition and the apparent absence of cleaved caspase-3 in treated cells indicated that the death did not involve the classic apoptosis pathway. Cellular ultrastructure analyses, western immunoblots, and in situ immunofluorescence visualization of cellular microtubules revealed microtubule-acetylation-independent induction of autophagy as the facilitator of cell death. Together, the data indicate strong antiproliferative efficacy and a possible mechanism of action for these designer nanoparticles. Bm-GNPs, therefore, merit further investigations, including preclinical evaluations, for their therapeutic potential as inducers of non-apoptotic cell death.

[High LINC00626 expression promotes esophagogastric junction adenocarcinoma metastasis: the mediating role of the JAK1/STAT3/KHSRP axis].

OBJECTIVE: To investigate the role of JAK1/STAT3/KHSRP axis in mediating the regulatory effect of LINC00626 on progression of esophagogastric junction adenocarcinoma. METHODS: We collected surgical tumor and adjacent tissue specimens from 64 patients with esophagogastric junction adenocarcinoma and examined the expression levels of LINC00626 and KHSRP. qRT-PCR was used to detect the expressions of LINC00626 and KHSRP in 6 esophageal adenocarcinoma cell lines (OE-19, TE-7, Bic-1, Flo-1, SK-GT-4, and BE-3) and a normal esophageal epithelial cell line (HET-1A). OE-19 and TE-7 cell lines with stable LINC00626 knockdown and FLO-1 and SK-GT-4 cells stably overexpressing LINC00626 were constructed by lentiviral transfection, and the changes in proliferation, migration and invasion of the cells were evaluated using Cell Counting Kit-8 (CCK-8) assay and Transwell migration/invasion assay. The expressions of KHSRP and JAK/STAT pathway proteins in the transfected cells were detected with Western blotting. The effects of LINC006266 knockdown and overexpression on subcutaneous tumor formation and lung metastasis of OE-19 and FLO-1 cell xenografts were tested in nude mice. RESULTS: The expression levels of LINC00626 and KHSRP were significantly increased in esophagogastric junction adenocarcinoma tissues and in esophageal adenocarcinoma cells. LINC00626 knockdown obviously inhibited the proliferation, migration and invasion of esophageal adenocarcinoma cells in vitro and decreased their tumor formation and lung metastasis abilities in nude mice, while overexpression of LINC00626 produced the opposite effects. In esophageal adenocarcinoma cells, LINC0626 knockdown significantly decreased and LINC00626 overexpression strongly enhanced the phosphorylation of JAK1 and STAT3. CONCLUSION: High LINC00626 expression promotes esophageal-gastric junction adenocarcinoma metastasis by activating the JAK1/STAT3/KHSRP signal axis.

Clinicopathologic features, concurrent genomic alterations, and clinical outcomes of patients with KRAS G12D mutations in resected lung adenocarcinoma.

BACKGROUND: In light of the ongoing clinical development of KRAS G12D-specific inhibitors, we sought to investigate the clinicopathologic, co-occurring genomic features and outcomes of patients with KRAS G12D-mutant lung adenocarcinoma. METHODS: 3828 patients with completely resected primary lung adenocarcinomas were examined for KRAS mutations between 2008 and 2020. The association between KRAS G12D and clinicopathologic features, molecular profiles, and outcomes was investigated. RESULTS: 65 patients (1.7%) with KRAS G12D-mutant lung adenocarcinoma were identified. KRAS G12D mutation was more frequent in males, former/current smokers, radiologic solid tumors, and invasive mucinous adenocarcinoma. TP53 and STK11 were the two most frequent concomitant mutations in the KRAS G12D group. KRAS G12D mutation did not appear to be a prognostic factor in resected stage I-III lung adenocarcinomas, while KRAS non-G12D mutation was related to worse survival, especially in stage I tumors. KRAS G12D mutations were associated with positive but low (1-49%) PD-L1 expression compared to negative (<1%), while KRAS non-G12D mutation was associated with high PD-L1 expression (≥50%). TP53 co-mutation indicated higher PD-L1 expression, while STK11 co-mutation had a negligible impact on PD-L1 expression. Furthermore, data mining of MSK datasets from cBioPortal revealed that KRAS G12D and SKT11 co-mutation were associated with a diminished response to immunotherapy. CONCLUSIONS: KRAS G12D-mutant lung adenocarcinoma harbored unique clinicopathologic and genomic characteristics. Despite not being prognostic in resected lung adenocarcinoma, KRAS G12D might be a valuable biomarker in combination with certain co-mutations for identifying relevant subgroups of patients that could eventually influence treatment regimens.

Immune signature of small bowel adenocarcinoma and the role of tumor microenvironment.

In this editorial we comment on the article published "Clinical significance of programmed cell death-ligand expression in small bowel adenocarcinoma is determined by the tumor microenvironment". Small bowel adenocarcinoma (SBA) is a rare gastrointestinal neoplasm and despite the small intestine's significant surface area, SBA accounts for less than 3% of such tumors. Early detection is challenging and the reason arises from its asymptomatic nature, often leading to late-stage discovery and poor prognosis. Treatment involves platinum-based chemotherapy with a 5-fluorouracil combination, but the lack of effective chemotherapy contributes to a generally poor prognosis. SBAs are linked to genetic disorders and risk factors, including chronic inflammatory conditions. The unique characteristics of the small bowel, such as rapid cell renewal and an active immune system, contributes to the rarity of these tumors as well as the high intratumoral infiltration of immune cells is associated with a favorable prognosis. Programmed cell death-ligand 1 (PD-L1) expression varies across different cancers, with potential discrepancies in its prognostic value. Microsatellite instability (MSI) in SBA is associated with a high tumor mutational burden, affecting the prognosis and response to immunotherapy. The presence of PD-L1 and programmed cell death 1, along with tumor-infiltrating lymphocytes, plays a crucial role in the complex microenvironment of SBA and contributes to a more favorable prognosis, especially in the context of high MSI tumors. Stromal tumor-infiltrating lymphocytes are identified as independent prognostic indicators and the association between MSI status and a favorable prognosis, emphasizes the importance of evaluating the immune status of tumors for treatment decisions.

Immunohistochemical p16 overexpression and Rb loss correlate with high-risk human papillomavirus infection in endocervical adenocarcinomas.

AIMS: p16 is a sensitive surrogate marker for transcriptionally active high-risk human papillomavirus (HR-HPV) infection in endocervical adenocarcinoma (ECA); however, its specificity is not perfect. METHODS AND RESULTS: We examined p16 and Rb expressions by immunohistochemistry (IHC) and the transcriptionally active HR-HPV infection by mRNA in-situ hybridisation (ISH) with histological review in 108 ECA cases. Thirteen adenocarcinomas of endometrial or equivocal origin (six endometrioid and seven serous carcinomas) were compared as the control group. HR-HPV was detected in 83 of 108 ECA cases (77%), including five HPV-associated adenocarcinomas in situ and 78 invasive HPV-associated adenocarcinomas. All 83 HPV-positive cases showed consistent morphology, p16 positivity and partial loss pattern of Rb. Among the 25 cases of HPV-independent adenocarcinoma, four (16%) were positive for p16, and of these four cases, three of 14 (21%) were gastric type adenocarcinomas and one of 10 (10%) was a clear cell type adenocarcinoma. All 25 HPV-independent adenocarcinomas showed preserved expression of Rb irrespective of the p16 status. Similarly, all 13 cases of the control group were negative for HR-HPV with preserved expression of Rb, even though six of 13 (46%) cases were positive for p16. Compared with p16 alone, the combination of p16 overexpression and Rb partial loss pattern showed equally excellent sensitivity (each 100%) and improved specificity (100 versus 73.6%) and positive predictive values (100 versus 89.2%) in the ECA and control groups. Furthermore, HR-HPV infection correlated with better prognosis among invasive ECAs. CONCLUSIONS: The results suggest that the combined use of p16 and Rb IHC could be a reliable method to predict HR-HPV infection in primary ECAs and mimics. This finding may contribute to prognostic prediction and therapeutic strategy.

A novel lncRNA-hidden polypeptide regulates malignant phenotypes and pemetrexed sensitivity in A549 pulmonary adenocarcinoma cells.

The advance of high-throughput sequencing enhances the discovery of short ORFs embedded in long non-coding RNAs (lncRNAs). Here, we uncovered the production and biological activity of lncRNA-hidden polypeptides in lung adenocarcinoma (LUAD). In the present study, bioinformatics was used to screen the lncRNA-hidden polypeptides in LUAD. Analysis of protein expression was done by western blot or immunofluorescence assay. The functions of the polypeptide were determined by detecting its effects on cell viability, proliferation, migration, invasion, and pemetrexed (PEM) sensitivity. The protein interactors of the polypeptide were analyzed by mass spectrometry after Co-immunoprecipitation (Co-IP) assay. The results showed that the lncRNA LINC00954 was confirmed to encode a novel polypeptide LINC00954-ORF. The polypeptide had tumor-suppressor features in A549 cells by repressing cell growth, motility and invasion. Moreover, the polypeptide enhanced PEM sensitivity and suppressed growth in A549/PEM cells. The protein interactors of this polypeptide had close correlations with RNA processing, amide metabolic process, translation, RNA binding, RNA transport, and DNA replication. As a conclusion, the LINC00954-ORF polypeptide embedded in lncRNA LINC00954 possesses tumor-suppressor features in A549 and PEM-resistant A549 cells and sensitizes PEM-resistant A549 cells to PEM, providing evidence that the LINC00954-ORF polypeptide is a potential anti-cancer agent in LUAD.

GPX3-Mediated Oxidative Stress Affects Pyrimidine Metabolism Levels in Stomach Adenocarcinoma via the AMPK/mTOR Pathway.

Background: Amino acid metabolism, including ATP production, nucleotide synthesis, and redox homeostatic processes, are associated with proliferation and differentiation of tumor cells. This study aimed to identify novel prognostic biomarkers and potential therapeutic targets of amino acid metabolism-related genes for stomach adenocarcinoma (STAD). Methods: RNA sequencing transcriptome data in the TCGA-STAD (training set) and GTEx datasets (validation set) were used. The LIMMA R program enabled the differentially expressed amino acid metabolism-related genes (AAMRGs) to be found. A prognostic risk score model based on clinical phenotypic features was built using LASSO regression and step multi-Cox analyses. Gene set enrichment analysis (GSEA) was used to find potential molecular pathways associated with STAD. Hierarchical cluster analysis was used to evaluate pyrimidine metabolism. Cultured STAD cells assessed the proliferation of STAD and upregulation of GPX3 expression by CCK8 and flow cytometry. Transwell and wound healing assays assessed the impact of GPX3 on invasion and migration of STAD cells. Western blot and qRT-PCR were used to measure changes in pyrimidine metabolism-related markers and active molecules involved in the AMPK/mTOR signaling pathway. Results: Three AAMRGs, DNMT1, F2R, and GPX3, could independently predict the course of STAD. Pyrimidine metabolism appeared to be significantly associated with these by GSEA and clustering analyses. Pyrimidine metabolism was negatively correlated with GPX3. Functional studies using an overexpressed GPX3 plasmid showed an enhanced migration and invasion of STAD cells as well as the expression of genes associated with pyrimidine metabolism and the AMPK/mTOR signaling pathway. By using a CAD siRNA, it was found that that GPX3 affected 5-fluorouracil resistance during de novo synthesis of pyrimidine through the CAD-UMPS signaling axis. Conclusions: GPX3 which regulates the level of pyrimidine metabolism through the AMPK/mTOR pathway was found to be closely associated with STAD. Our findings demonstrate GPX3 is a reliable biomarker for the prognosis of amino acid metabolism and a probable target for STAD therapy.

CLCA1 is Poorly Expressed in Stomach Adenocarcinoma and Correlates with Immune Infiltration / CLCA1 se Expresa Deficientemente en el Adenocarcinoma de Estómago y se Correlaciona con la Infiltración Inmune

SUMMARY: Calcium-activated chloride channel regulator 1 (CLCA1) is associated with cancer progression. The expression and immunologic function of CLCA1 in stomach adenocarcinoma (STAD) remain unclear. In this investigation, the expression of CLCA1 in STAD tissues and its involvement in the progression and immune response of STAD were examined using databases such as cBioPortal, TISIDB, and UALCAN. In order to validate the expression level of CLCA1 protein in gastric adenocarcinoma, thirty clinical tissue specimens were gathered for immunohistochemical staining. The findings indicated a downregulation of CLCA1 in STAD patients, which was correlated with race, age, cancer grade, Helicobacter pylori infection, and molecular subtype. Through the examination of survival analysis, it was identified that diminished levels of CLCA1 within gastric cancer cases were linked to decreased periods of post-progression survival (PPS), overall survival (OS), and first progression (FP) (P<0.05). The CLCA1 mutation rate was lower in STAD, but the survival rate was higher in the variant group. The correlation between the expression level of CLCA1 and the levels of immune infiltrating cells in STAD, as well as the immune activating molecules, immunosuppressive molecules, MHC molecules, chemokines, and their receptor molecules, was observed. Gene enrichment analysis revealed that CLCA1 may be involved in STAD progression through systemic lupus erythematosus (SLE), proteasome, cell cycle, pancreatic secretion, and PPAR signaling pathways. In summary, CLCA1 is anticipated to function as a prognostic marker for patients with STAD and is linked to the immunization of STAD.

El regulador 1 del canal de cloruro activado por calcio (CLCA1) está asociado con la progresión del cáncer. La expresión y la función inmunológica de CLCA1 en el adenocarcinoma de estómago (STAD) aún no están claras. En esta investigación, se examinó la expresión de CLCA1 en tejidos STAD y su participación en la progresión y respuesta inmune de STAD utilizando bases de datos como cBioPortal, TISIDB y UALCAN. Para validar el nivel de expresión de la proteína CLCA1 en el adenocarcinoma gástrico, se recolectaron treinta muestras de tejido clínico para tinción inmunohistoquímica. Los hallazgos indicaron una regulación negativa de CLCA1 en pacientes con STAD, que se correlacionó con la raza, la edad, el grado del cáncer, la infección por Helicobacter pylori y el subtipo molecular. Mediante el examen del análisis de supervivencia, se identificó que los niveles reducidos de CLCA1 en los casos de cáncer gástrico estaban relacionados con períodos reducidos de supervivencia posterior a la progresión (PPS), supervivencia general (OS) y primera progresión (FP) (P <0,05). La tasa de mutación CLCA1 fue menor en STAD, pero la tasa de supervivencia fue mayor en el grupo variante. Se observó la correlación entre el nivel de expresión de CLCA1 y los niveles de células inmunes infiltrantes en STAD, así como las moléculas activadoras inmunes, moléculas inmunosupresoras, moléculas MHC, quimiocinas y sus moléculas receptoras. El análisis de enriquecimiento genético reveló que CLCA1 puede estar involucrado en la progresión de STAD a través del lupus eritematoso sistémico (LES), el proteasoma, el ciclo celular, la secreción pancreática y las vías de señalización de PPAR. En resumen, se prevé que CLCA1 funcione como un marcador de pronóstico para pacientes con STAD y está vinculado a la inmunización de STAD.

ING3 inhibits the malignant progression of lung adenocarcinoma by negatively regulating ITGB4 expression to inactivate Src/FAK signaling.

Lung adenocarcinoma (LUAD) is the most commonly diagnosed subtype of lung cancer worldwide. Inhibitor of growth 3 (ING3) serves as a tumor suppressor in many cancers. This study aimed to elucidate the role of ING3 in the progression of LUAD and investigate the underlying mechanism related to integrin ß4 (ITGB4) and Src/focal adhesion kinase (FAK) signaling. ING3 expression in LUAD tissues and the correlation between ING3 expression and prognosis were analyzed by bioinformatics databases. After evaluating ING3 expression in LUAD cells, ING3 was overexpressed to assess the proliferation, cell cycle arrest, migration and invasion of LUAD cells. Then, ITGB4 was upregulated to observe the changes of malignant activities in ING3-overexpressed LUAD cells. The transplantation tumor model of NCI-H1975 cells in nude mice was established to analyze the antineoplastic effect of ING3 upregulation in vivo. Downregulated ING3 expression was observed in LUAD tissues and cells and lower ING3 expression predicated the poor prognosis. ING3 upregulation restrained the proliferation, migration, invasion and induced the cell cycle arrest of NCI-H1975 cells. Additionally, ITGB4 expression was negatively correlated with ING3 expression in LUAD tissue. ING3 led to reduced expression of ITGB4, Src and p-FAK. Moreover, ITGB4 overexpression alleviated the effects of ING3 upregulation on the malignant biological properties of LUAD cells. It could be also found that ING3 upregulation limited the tumor volume, decreased the expression of ITGB4, Src and p-FAK, which was restored by ITGB4 overexpression. Collectively, ING3 inhibited the malignant progression of LUAD by negatively regulating ITGB4 expression to inactivate Src/FAK signaling.

The relationship between DNA mismatch repair gene and other prognostic parameters in pancreatic adenocarcinoma.

The aim of the study was to determine DNA mismatch repair (MMR) proteins by immunohistochemically using MLH1, MSH2, MSH6, and PMS2 antibodies in patients diagnosed as pancreatic ductal adenocarcinoma and to assess its relationship with histopathological and clinical prognostic parameters. Fifty cases with a diagnosis of pancreatic ductal adenocarcinoma who underwent surgical resection, were included in the study. Demographic and histopathological features of the patients were collected from the medical records. The relationships between microsatellite status and prognostic parameters were determined. The mean age of the patients was 66.5 ± 9.5 years (range: 47-87) and male/female ratio was 1.63 (31/19). No errors were detected in DNA MMR proteins in any of the cases, and were classified as microsatellite stable. The mean tumor diameter was 4.01 ± 1.77 cm and 74% of the tumors were localized in the pancreatic head. All of the cases had lymphatic invasion, whereas vascular invasion was detected in only 78% and perineural invasion in 98% of the patients. When the relationship between prognostic parameters and survival was evaluated, statistically significant correlation was observed in patient age and histopathological parameters such as tumor diameter, status of surgical margins, and vascular invasion (p < 0.05). Age, tumor size, presence of tumor at surgical margins, vascular invasion, and adjuvant treatment were correlated with survival. Although microsatellite instability was not detected in our cases, it is important to determine the microsatellite status by immunohistochemistry for predicting the chemotherapy response and determining the immunotherapy option in pancreatic adenocarcinomas.

Cytidine Deaminase Resolves Replicative Stress and Protects Pancreatic Cancer from DNA-Targeting Drugs.

Cytidine deaminase (CDA) functions in the pyrimidine salvage pathway for DNA and RNA syntheses and has been shown to protect cancer cells from deoxycytidine-based chemotherapies. In this study, we observed that CDA was overexpressed in pancreatic adenocarcinoma from patients at baseline and was essential for experimental tumor growth. Mechanistic investigations revealed that CDA localized to replication forks where it increased replication speed, improved replication fork restart efficiency, reduced endogenous replication stress, minimized DNA breaks, and regulated genetic stability during DNA replication. In cellular pancreatic cancer models, high CDA expression correlated with resistance to DNA-damaging agents. Silencing CDA in patient-derived primary cultures in vitro and in orthotopic xenografts in vivo increased replication stress and sensitized pancreatic adenocarcinoma cells to oxaliplatin. This study sheds light on the role of CDA in pancreatic adenocarcinoma, offering insights into how this tumor type modulates replication stress. These findings suggest that CDA expression could potentially predict therapeutic efficacy and that targeting CDA induces intolerable levels of replication stress in cancer cells, particularly when combined with DNA-targeted therapies. SIGNIFICANCE: Cytidine deaminase reduces replication stress and regulates DNA replication to confer resistance to DNA-damaging drugs in pancreatic cancer, unveiling a molecular vulnerability that could enhance treatment response.

Elevated enteric putrescine suppresses differentiation of intestinal germinal center B cells.

The dysregulation of B cell maturation and putrescine metabolism has been implicated in various diseases. However, the causal relationship between them and the underlying mechanisms remain unclear. In this study, we investigated the impact of exogenous putrescine on B cell differentiation in the intestinal microenvironment. Our results demonstrated that administration of exogenous putrescine significantly impaired the proportion of germinal center B (GC B) cells in Peyer's patches (PPs) and lamina propria. Through integration of bulk RNA sequencing and single-cell RNA sequencing (scRNA-seq), we identified putrescine-mediated changes in gene drivers, including those involved in the B cell receptor (BCR) signaling pathway and fatty acid oxidation. Furthermore, putrescine drinking disrupted T-B cell interactions and increased reactive oxygen species (ROS) production in B cells. In vitro activation of B cells confirmed the direct suppression of putrescine on GC B cells differentiation and ROS production. Additionally, we explored the Pearson correlations between putrescine biosynthesis activity and B cell infiltration in pan-cancers, revealing negative correlations in colon adenocarcinoma, stomach adenocarcinoma, and lung adenocarcinoma, but positive correlations in liver hepatocellular carcinoma, and breast invasive carcinoma. Our findings provided novel insights into the suppressive effects of elevated enteric putrescine on intestinal B cells differentiation and highlighted the complex and distinctive immunoregulatory role of putrescine in different microenvironments. These findings expand our understanding of the role of polyamines in B cell immunometabolism and related diseases.

Oncogenic Fatty Acid Metabolism Rewires Energy Supply Chain in Gastric Carcinogenesis.

BACKGROUND & AIMS: Gastric carcinogenesis develops within a sequential carcinogenic cascade from precancerous metaplasia to dysplasia and adenocarcinoma, and oncogenic gene activation can drive the process. Metabolic reprogramming is considered a key mechanism for cancer cell growth and proliferation. However, how metabolic changes contribute to the progression of metaplasia to dysplasia remains unclear. We have examined metabolic dynamics during gastric carcinogenesis using a novel mouse model that induces Kras activation in zymogen-secreting chief cells. METHODS: We generated a Gif-rtTA;TetO-Cre;KrasG12D (GCK) mouse model that continuously induces active Kras expression in chief cells after doxycycline treatment. Histologic examination and imaging mass spectrometry were performed in the GCK mouse stomachs at 2 to 14 weeks after doxycycline treatment. Mouse and human gastric organoids were used for metabolic enzyme inhibitor treatment. The GCK mice were treated with a stearoyl- coenzyme A desaturase (SCD) inhibitor to inhibit the fatty acid desaturation. Tissue microarrays were used to assess the SCD expression in human gastrointestinal cancers. RESULTS: The GCK mice developed metaplasia and high-grade dysplasia within 4 months. Metabolic reprogramming from glycolysis to fatty acid metabolism occurred during metaplasia progression to dysplasia. Altered fatty acid desaturation through SCD produces a novel eicosenoic acid, which fuels dysplastic cell hyperproliferation and survival. The SCD inhibitor killed both mouse and human dysplastic organoids and selectively targeted dysplastic cells in vivo. SCD was up-regulated during carcinogenesis in human gastrointestinal cancers. CONCLUSIONS: Active Kras expression only in gastric chief cells drives the full spectrum of gastric carcinogenesis. Also, oncogenic metabolic rewiring is an essential adaptation for high-energy demand in dysplastic cells.

Mutation profile and programmed death ligand 1 status of patients with non-small cell lung cancer diagnosed with "adenocarcinoma" and "non-small cell carcinoma favor adenocarcinoma".

BACKGROUND: The terminology for lung cancer diagnosis in small biopsies was adopted in the 2015 World Health Organization classification. If non-small cell lung cancer (NSCLC) has no clear adenocarcinoma (AD) or squamous cell carcinoma morphology, the tumor is further classified based on mucin or immunohistochemical staining as NSCLC favor AD (NFAD), NSCLC favor squamous cell carcinoma, or NSCLC not otherwise specified. Since this new term was defined, the difference between AD and NFAD has not yet been fully explored. This study aimed to examine the differences in clinical background, gene alteration frequency, and programmed death ligand 1 (PD-L1) expression. METHODS: We included patients diagnosed with AD or NFAD with small samples, and who underwent testing with the Oncomine Dx target test between August 2019 and April 2023 in Kanagawa Cancer Center. RESULTS: This study comprised 268 patients. A total of 96 patients underwent surgery after AD or NFAD diagnosis. The clinical stage was more advanced and pathological N0 was lower in NFAD than in AD. The pathology of the surgical specimens revealed that solid predominant AD was significantly more common in NFAD than in AD (p < 0.001). In both AD and NFAD, EGFR mutation was the most frequent gene alteration, followed by KRAS mutation. The frequency of EGFR mutations was significantly higher in AD than in NFAD. PD-L1 expression was significantly higher in NFAD than in AD (p < 0.001). CONCLUSION: This study shows a clear difference between AD and NFAD in terms of cancer progression, pathological features of the main tumor, genetic characteristics, and PD-L1 expression.

Role of the mechanical microenvironment on CD-44 expression of breast adenocarcinoma in response to radiotherapy.

The biological effects of ionizing radiation are exploited in the clinical practice of radiotherapy to destroy tumour cells while sparing the surrounding normal tissue. While most of the radiotherapy research focused on DNA damage and repair, recently a great attention is going to cells' interactions with the mechanical microenvironment of both malignant and healthy tissues after exposure. In fact, the stiffness of the extracellular matrix can modify cells' motility and spreading through the modulation of transmembrane proteins and surface receptors' expression, such as CD-44. CD-44 receptor has held much interest also in targeted-therapy due to its affinity with hyaluronic acid, which can be used to functionalize biodegradable nanoparticles loaded with chemotherapy drugs for targeted therapy. We evaluated changes in CD-44 expression in two mammary carcinoma cell lines (MCF10A and MDA-MB-231) after exposure to X-ray (2 or 10 Gy). To explore the role of the mechanical microenvironment, we mimicked tissues' stiffness with polyacrylamide's substrates producing two different elastic modulus values (0.5 and 15 kPa). We measured a dose dependent increase in CD-44 relative expression in tumour cells cultured in a stiffer microenvironment. These findings highlight a crucial connection between the mechanical properties of the cell's surroundings and the post-radiotherapy expression of surface receptors.

Elevated levels of peripheral Th17 cells and Th17-related cytokines in patients with periampullary adenocarcinoma.

AIM: Periampullary adenocarcinoma (PAC) is a malignant tumor originating at the ampulla of Vater, distal common bile duct, head of the pancreas, ampulla and duodenum. The levels of circulating Th17 cells and Th17-related cytokines in patients with PAC remain unreported. Therefore, the aim of this study was to determine the levels of circulating Th17 cells and Th17-related cytokines in patients with PAC. MATERIALS AND METHODS: Flow cytometry was used to measure Th17 cell proportions in PBMCs from 60 PAC patients and 30 healthy controls. Enzyme-linked immunosorbent assay (ELISA) was used to quantify IL-17A and IL-23 levels in serum samples, while quantitative reverse transcription polymerase chain reaction (qRT-PCR) assessed IL-17A mRNA expression and Th17-related transcription factors (RORγt and STAT3) in tissue samples. RESULTS: The findings showed a substantial increase in Th17 cell percentages, elevated concentrations of IL-17A and IL-23, and higher mRNA expression levels of IL-17A, RORγt, and STAT3 in patients with PAC when compared to healthy controls (HCs). CONCLUSION: Th17 cells play an important role in the pathogenesis of PAC and may represent potential therapeutic targets.

Breast adenocarcinoma cells adhere stronger to brain pericytes than to endothelial cells.

Most of the malignancies detected within the brain parenchyma are of metastatic origin. As the brain lacks classical lymphatic circulation, the primary way for metastasis relies on hematogenous routes. Dissemination of metastatic cells to the brain implies attachment to the luminal surface of brain endothelial cells, transmigration through the vessel wall, and adhesion to the brain surface of the vasculature. During this process, tumor cells must interact with brain endothelial cells and later on with pericytes. Physical interaction between tumor cells and brain vascular cells might be crucial in the successful extravasation of metastatic cells through blood vessels and later in their survival within the brain environment. Therefore, we applied single-cell force spectroscopy to investigate the nanoscale adhesive properties of living breast adenocarcinoma cells to brain endothelial cells and pericytes. We found target cell type-dependent adhesion characteristics, i.e. increased adhesion of the tumor cells to pericytes in comparison to endothelial cells, which underlines the existence of metastatic potential-related nanomechanical differences relying partly on membrane tether dynamics. Varying adhesion strength of the tumor cells to different cell types of brain vessels presumably reflects the transitory adhesion to endothelial cells before extravasation and the long-lasting strong interaction with pericytes during survival and proliferation in the brain. Our results highlight the importance of specific mechanical interactions between tumor cells and host cells during metastasis formation.