Appendectomy and Long-term Colorectal Cancer Incidence, Overall and by Tumor Fusobacterium nucleatum Status.

OBJECTIVE: To test hypotheses that appendectomy history might lower long-term colorectal cancer risk and that the risk reduction might be strong for tumors enriched with Fusobacterium nucleatum, bacterial species implicated in colorectal carcinogenesis. BACKGROUND: The absence of the appendix, an immune system organ and a possible reservoir of certain pathogenic microbes, may affect the intestinal microbiome, thereby altering long-term colorectal cancer risk. METHODS: Utilizing databases of prospective cohort studies, namely the Nurses' Health Study and the Health Professionals Follow-up Study, we examined the association of appendectomy history with colorectal cancer incidence overall and subclassified by the amount of tumor tissue Fusobacterium nucleatum​​ (Fusobacterium animalis). We used an inverse probability weighted multivariable-adjusted duplication-method Cox proportional hazards regression model. RESULTS: During the follow-up of 139,406 participants (2,894,060 person-years), we documented 2811 incident colorectal cancer cases, of which 1065 cases provided tissue F. nucleatum analysis data. The multivariable-adjusted hazard ratio of appendectomy for overall colorectal cancer incidence was 0.92 (95% CI, 0.84-1.01). Appendectomy was associated with lower F. nucleatum-positive cancer incidence (multivariable-adjusted hazard ratio, 0.53; 95% CI, 0.33-0.85; P=0.0079), but not F. nucleatum-negative cancer incidence (multivariable-adjusted hazard ratio, 0.98; 95% CI, 0.83-1.14), suggesting a differential association by F. nucleatum status (Pheterogeneity=0.015). This differential association appeared to persist in various participant/patient strata including tumor location and microsatellite instability status. CONCLUSIONS: Appendectomy likely lowers the future long-term incidence of F. nucleatum-positive (but not F. nucleatum-negative) colorectal cancer. Our findings do not support the existing hypothesis that appendectomy may increase colorectal cancer risk.

Cell adhesion molecule-1 shedding induces apoptosis of renal epithelial cells and exacerbates human nephropathies.

Chronic kidney disease (CKD) is an important problem throughout the world, associated with the increase of blood urea nitrogen (BUN) and serum creatinine (sCre) and with renal tubular injuries. It is crucial to elucidate the molecular mechanisms of renal injuries to identify the new therapeutics and early diagnostic methods. We focused on cell adhesion molecule-1 (CADM1) protein. CADM1, its isoform SP4, is expressed in the epithelial cells of various tissues, including renal distal tubules, localized on the lateral cell membrane, mediates cell-cell adhesion via trans-homophilic binding, and interacts with various proteins. We previously reported that its expression was downregulated by post-proteolytic cleavage (α- and ß-shedding) in pulmonary diseases. To investigate whether CADM1 α-shedding occurs in human nephropathies, we performed Western blotting and immunohistochemical analysis of specimens with arterionephrosclerosis (AS) and diabetic nephropathy (DN) from autopsied kidneys. CADM1 α-shedding was induced in AS and DN kidneys and derived from the decrease in full-length CADM1 (FL-CADM1) and increase of the COOH-terminal fragment (α-CTF). In particular, the reduced FL-CADM1 level was correlated with tubular and tubulointerstitial injuries and the increases in BUN and sCre levels. Apoptosis of renal tubular epithelial cells (TECs) was promoted in both nephropathies, and it was significantly correlated with the decrease in the FL-CADM1. Furthermore, FL-CADM1 knockdown by small interfering RNA downregulated anti-apoptotic Bcl-2 protein and promoted apoptosis of cultured renal TECs. The present study suggests that the reduction of FL-CADM1 leads to renal TEC apoptosis and could exacerbate renal tubular and tubulointerstitial injuries, which contribute to the development of CKD.

Nivolumab-induced acute granulomatous tubulointerstitial nephritis in a patient with gastric cancer.

We here report a case of nivolumab-induced acute granulomatous tubulointerstitial nephritis in a patient with gastric cancer. A 68-year-old woman with recurrent gastric cancer developed acute kidney injury associated with kidney enlargement and urinary leukocytes after 38 cycles of nivolumab treatment. A diagnosis of acute granulomatous tubulointerstitial nephritis was made based on kidney biopsy findings. Immunohistochemistry revealed expression of programmed cell death-ligand 1 (PD-L1) in degenerated epithelial cells of collecting tubules. Among infiltrating immune cells, aggregation of T cells was more extensive than that of B cells, with CD4+ T cells outnumbering CD8+ T cells, consistent with the relative numbers of these cells in the circulation. Treatment with methylprednisolone (1.0 mg/kg daily) led to a rapid improvement in renal function and reduction in the number of circulating CD4+ T cells. Prompt administration of high-dose corticosteroid is thus recommended after diagnosis of this adverse event of nivolumab treatment by kidney biopsy.

Manifestation of osteoblastic phenotypes in the sarcomatous component of epithelial carcinoma and sarcomatoid carcinoma.

Epithelial carcinomas occasionally have sarcomatous components that consist primarily of spindle and cuboidal cells, which often resemble osteoblasts. Sarcomatoid carcinomas consist of similar cells. Recent studies have characterized these phenomena as a manifestation of epithelial-mesenchymal transition in carcinoma cells, but the mesenchymal phenotypes that manifest in sarcomatous cells of epithelial carcinomas are not well understood. Here, we examined the expression profiles of four osteoblastic differentiation biomarkers in the sarcomatous components of multiple carcinoma types, including five renal clear cell, four breast invasive ductal, two esophageal, one maxillary squamous cell, three larynx, three lung, one liver, and one skin sarcomatoid carcinoma. Expression was analyzed by immunohistochemistry using antibodies against cell adhesion molecule 1, a member of the IgCAM superfamily, osterix transcription factor (Osterix), cluster of differentiation 151, a transmembrane 4 superfamily member, and alkaline phosphatase. Immunostaining intensity was rated in scale 0 (negative), 0.5 (weak), and 1 (strong) for each marker, and the four scale values were summed to calculate osteoblastic scores. In all, 10 cases had a osteoblastic score ≥3, and all of these 10 cases were cell adhesion molecule 1- and Osterix-positive. Eight and five of the nine samples with a osteoblastic score <3 were negative for cell adhesion molecule 1 ( p < 0.0001) and Osterix ( p = 0.006), respectively. The other markers showed no statistical significance. These results indicate that osteoblastic differentiation can occur in carcinoma cells and that cell adhesion molecule 1 could be a useful marker for identifying this phenomenon in carcinoma tissues.

Heparan sulfate 6-O-endosulfatases, Sulf1 and Sulf2, regulate glomerular integrity by modulating growth factor signaling.

Glomerular integrity and functions are maintained by growth factor signaling. Heparan sulfate, the major component of glomerular extracellular matrixes, modulates growth factor signaling, but its roles in glomerular homeostasis are unknown. We investigated the roles of heparan sulfate 6-O-endosulfatases, sulfatase (Sulf)1 and Sulf2, in glomerular homeostasis. Both Sulf1 and Sulf2 were expressed in the glomeruli of wild-type (WT) mice. Sulf1 and Sulf2 double-knockout (DKO) mice showed glomerular hypercellularity, matrix accumulation, mesangiolysis, and glomerular basement membrane irregularity. Platelet-derived growth factor (PDGF)-B and PDGF receptor-ß were upregulated in Sulf1 and Sulf2 DKO mice compared with WT mice. Glomeruli from Sulf1 and Sulf2 DKO mice in vitro stimulated by either PDGF-B, VEGF, or transforming growth factor-ß similarly showed reduction of phospho-Akt, phospho-Erk1/2, and phospho-Smad2/3, respectively. Since glomerular lesions in Sulf1 and Sulf2 DKO mice were reminiscent of diabetic nephropathy, we examined the effects of Sulf1 and Sulf2 gene disruption in streptozotocin-induced diabetes. Diabetic WT mice showed an upregulation of glomerular Sulf1 and Sulf2 mRNA by in situ hybridization. Diabetic DKO mice showed significant increases in albuminuria and serum creatinine and an acceleration of glomerular pathology without glomerular hypertrophy; those were associated with a reduction of glomerular phospho-Akt. In conclusion, Sulf1 and Sulf2 play indispensable roles to maintain glomerular integrity and protective roles in diabetic nephropathy, probably by growth factor modulation.

Podocyte injury-driven lipid peroxidation accelerates the infiltration of glomerular foam cells in focal segmental glomerulosclerosis.

Intracapillary foam cell infiltration with podocyte alterations is a characteristic pathology of focal segmental glomerulosclerosis (FSGS). We investigated the possible role of podocyte injury in glomerular macrophage and foam cell infiltration in a podocyte-selective injury model (NEP25 mice) and hypercholesterolemic model [low-density lipoprotein receptor deficiency (LDLR(-/-)) mice] with doxorubicin-induced nephropathy. Acute podocyte selective injury alone failed to induce glomerular macrophages in the NEP25 mice. However, in the doxorubicin-treated hypercholesterolemic LDLR(-/-) mice, glomerular macrophages/foam cells significantly increased and were accompanied by lipid deposition and the formation and ingestion of oxidized phospholipids (oxPLs). Glomerular macrophages significantly correlated with the amount of glomerular oxPL. The NEP25/LDLR(-/-) mice exhibited severe hypercholesterolemia, glomerular lipid deposition, and renal dysfunction. Imaging mass spectrometry revealed that a major component of oxidized low-density lipoprotein, lysophosphatidylcholine 16:0 and 18:0, was present only in the glomeruli of NEP25/LDLR(-/-) mice. Lysophosphatidylcholine 16:0 stimulated mesangial cells and macrophages, and lysophosphatidylcholine 18:0 stimulated glomerular endothelial cells to express adhesion molecules and chemokines, promoting macrophage adhesion and migration in vitro. In human FSGS, glomerular macrophage-derived foam cells contained oxPLs accompanied by the expression of chemokines in the tuft. In conclusion, glomerular lipid modification represents a novel pathology by podocyte injury, promoting FSGS. Podocyte injury-driven lysophosphatidylcholine de novo accelerated glomerular macrophage-derived foam cell infiltration via lysophosphatidylcholine-mediated expression of adhesion molecules and chemokines in glomerular resident cells.

Podocyte injury-driven intracapillary plasminogen activator inhibitor type 1 accelerates podocyte loss via uPAR-mediated ß1-integrin endocytosis.

Podocyte-endothelial cell cross-talk is paramount for maintaining the filtration barrier. The present study investigated the endothelial response to podocyte injury and its subsequent role in glomerulosclerosis using the podocyte-specific injury model of NEP25/LMB2 mice. NEP25/LMB2 mice showed proteinuria and local podocyte loss accompanied by thrombotic microangiopathy on day 8. Mice showed an increase of glomerular plasminogen activator inhibitor type 1 (PAI-1) mRNA and aberrant endothelial PAI-1 protein already on day 1, before thrombosis and proteinuria. A PAI-1-specific inhibitor reduced proteinuria and thrombosis and preserved podocyte numbers in NEP25/LMB2 mice by stabilization of ß1-integrin translocation. Heparin loading significantly reduced thrombotic formation, whereas proteinuria and podocyte numbers were unchanged. Immortalized podocytes treated with PAI-1 and the urokinase plasminogen activator (uPA) complex caused significant cell detachment, whereas podocytes treated with PAI-1 or uPA alone or with the PAI-1/uPA complex pretreated with an anti-uPA receptor (uPAR) antibody failed to cause detachment. Confocal microscopy and cell surface biotinylation experiments showed that internalized ß1-integrin was found together with uPAR in endocytotic vesicles. The administration of PAI-1 inhibitor or uPAR-blocking antibody protected cultured podocytes from cell detachment. In conclusion, PAI-1/uPA complex-mediated uPAR-dependent podocyte ß1-integrin endocytosis represents a novel mechanism of glomerular injury leading to progressive podocytopenia. This aberrant cross-talk between podocytes and endothelial cells represents a feedforward injury response driving podocyte loss and progressive glomerulosclerosis.

The direction and role of phenotypic transition between podocytes and parietal epithelial cells in focal segmental glomerulosclerosis.

Focal segmental glomerulosclerosis (FSGS) is a podocyte disease. Among the various histologies of FSGS, active epithelial changes, hyperplasia, as typically seen in the collapsing variant, indicates disease progression. Using a podocyte-specific injury model of FSGS carrying a genetic podocyte tag combined with double immunostaining by different sets of podocytes and parietal epithelial cell (PEC) markers [nestin/Pax8, Wilms' tumor-1 (WT1)/claudin1, and podocalyxin/Pax2], we investigated the direction of epithelial phenotypic transition and its role in FSGS. FSGS mice showed progressive proteinuria and renal dysfunction often accompanied by epithelial hyperplasia, wherein 5-bromo-4-chloro-3-indoyl ß-d-galactoside (X-gal)-positive podocyte-tagged cells were markedly decreased. The average numbers of double-positive cells in all sets of markers were significantly increased in the FSGS mice compared with the controls. In addition, the average numbers of double-positive cells for X-gal/Pax8, nestin/Pax8 and podocalyxin/Pax2 staining in the FSGS mice were comparable, whereas those of WT1/claudin1 were significantly increased. When we divided glomeruli from FSGS mice into those with FSGS lesions and those without, double-positive cells tended to be more closely associated with glomeruli without FSGS lesions compared with those with FSGS lesions. Moreover, the majority of double-positive cells appeared to be isolated and very rarely associated with FSGS lesions (1/1,997 glomeruli). This study is the first to show the incidence and localization of epithelial cells with phenotypical changes in FSGS using a genetic tag. The results suggest that the major direction of epithelial phenotypic transition in cellular FSGS is from podocytes to PECs and that these cells were less represented in the active lesions of FSGS.

Enrichment of Bacteroides fragilis and enterotoxigenic Bacteroides fragilis in CpG island methylator phenotype-high colorectal carcinoma.

OBJECTIVES: Data support that enterotoxigenic Bacteroides fragilis (ETBF) harbouring the Bacteroides fragilis toxin (bft) gene may promote colorectal tumourigenesis through the serrated neoplasia pathway. We hypothesized that ETBF may be enriched in colorectal carcinoma subtypes with high-level CpG island methylator phenotype (CIMP-high), BRAF mutation, and high-level microsatellite instability (MSI-high). METHODS: Quantitative PCR assays were designed to quantify DNA amounts of Bacteroides fragilis, ETBF, and each bft gene isotype (bft-1, bft-2, or bft-3) in colorectal carcinomas in the Health Professionals Follow-up Study and Nurses' Health Study. We used multivariable-adjusted logistic regression models with the inverse probability weighting method. RESULTS: We documented 4476 colorectal cancer cases, including 1232 cases with available bacterial data. High DNA amounts of Bacteroides fragilis and ETBF were positively associated with BRAF mutation (p ≤ 0.0003), CIMP-high (p ≤ 0.0002), and MSI-high (p < 0.0001 and p = 0.01, respectively). Multivariable-adjusted odds ratios (with 95% confidence interval) for high Bacteroides fragilis were 1.40 (1.06-1.85) for CIMP-high and 2.14 (1.65-2.77) for MSI-high, but 1.02 (0.78-1.35) for BRAF mutation. Multivariable-adjusted odds ratios for high ETBF were 2.00 (1.16-3.45) for CIMP-high and 2.86 (1.64-5.00) for BRAF mutation, but 1.09 (0.67-1.76) for MSI-high. Neither Bacteroides fragilis nor ETBF was associated with colorectal cancer-specific or overall survival. DISCUSSION: The tissue abundance of Bacteroides fragilis is associated with CIMP-high and MSI-high, whereas ETBF abundance is associated with CIMP-high and BRAF mutation in colorectal carcinoma. Our findings support the aetiological relevance of Bacteroides fragilis and ETBF in the serrated neoplasia pathway.

Aberrant Notch1-dependent effects on glomerular parietal epithelial cells promotes collapsing focal segmental glomerulosclerosis with progressive podocyte loss.

Collapsing focal segmental glomerulosclerosis (cFSGS) is a progressive kidney disease characterized by glomerular collapse with epithelial hyperplasia. Here we used a transgenic mouse model of cFSGS with immunotoxin-induced podocyte-specific injury to determine the role for Notch signaling in its pathogenesis. The mice exhibited progressive loss of podocytes and severe proteinuria concomitant with histological features of cFSGS. Hyperplastic epithelium was negative for genetic podocyte tags, but positive for the parietal epithelial cell marker claudin-1, and expressed Notch1, Jagged1, and Hes1 mRNA and protein. Enhanced Notch mRNA expression induced by transforming growth factor-ß1 in cultured parietal epithelial cells was associated with mesenchymal markers (α-smooth muscle actin, vimentin, and Snail1). Notch inhibition in vitro suppressed these phenotypic transcripts and Notch-dependent cell migration. Moreover, Notch inhibition in vivo significantly decreased parietal epithelial cell lesions but worsened proteinuria and histopathology in our cFSGS model. Thus, aberrant Notch1-mediated parietal epithelial cell migration with phenotypic changes appears to underlie the pathogenesis of cFSGS. Parietal epithelial cell hyperplasia may also represent an adaptive response to compensate for a disrupted filtration barrier with progressive podocyte loss.

Inverse relationship between Fusobacterium nucleatum amount and tumor CD274 (PD-L1) expression in colorectal carcinoma.

Objectives: The CD274 (programmed cell death 1 ligand 1, PD-L1)/PDCD1 (programmed cell death 1, PD-1) immune checkpoint axis is known to regulate the antitumor immune response. Evidence also supports an immunosuppressive effect of Fusobacterium nucleatum. We hypothesised that tumor CD274 overexpression might be inversely associated with abundance of F. nucleatum in colorectal carcinoma. Methods: We assessed tumor CD274 expression by immunohistochemistry and F. nucleatum DNA within tumor tissue by quantitative PCR in 812 cases among 4465 incident rectal and colon cancer cases that had occurred in two prospective cohort studies. Multivariable logistic regression analyses with inverse probability weighting were used to adjust for selection bias because of tissue data availability and potential confounders including microsatellite instability status, CpG island methylator phenotype, LINE-1 methylation level and KRAS, BRAF and PIK3CA mutations. Results: Fusobacterium nucleatum DNA was detected in tumor tissue in 109 (13%) cases. Tumor CD274 expression level was inversely associated with the amount of F. nucleatum in colorectal cancer tissue (P = 0.0077). For one category-unit increase in three ordinal F. nucleatum categories (negative vs. low vs. high), multivariable-adjusted odds ratios (with 95% confidence interval) of the low, intermediate and high CD274 categories (vs. negative) were 0.78 (0.41-1.51), 0.64 (0.32-1.28) and 0.50 (0.25-0.99), respectively (P trend = 0.032). Conclusions: Tumor CD274 expression level was inversely associated with the amount of F. nucleatum in colorectal cancer tissue, suggesting that different immunosuppressive mechanisms (i.e. PDCD1 immune checkpoint activation and tumor F. nucleatum enrichment) tend to be used by different tumor subgroups.

Histopathology images predict multi-omics aberrations and prognoses in colorectal cancer patients.

Histopathologic assessment is indispensable for diagnosing colorectal cancer (CRC). However, manual evaluation of the diseased tissues under the microscope cannot reliably inform patient prognosis or genomic variations crucial for treatment selections. To address these challenges, we develop the Multi-omics Multi-cohort Assessment (MOMA) platform, an explainable machine learning approach, to systematically identify and interpret the relationship between patients' histologic patterns, multi-omics, and clinical profiles in three large patient cohorts (n = 1888). MOMA successfully predicts the overall survival, disease-free survival (log-rank test P-value<0.05), and copy number alterations of CRC patients. In addition, our approaches identify interpretable pathology patterns predictive of gene expression profiles, microsatellite instability status, and clinically actionable genetic alterations. We show that MOMA models are generalizable to multiple patient populations with different demographic compositions and pathology images collected from distinctive digitization methods. Our machine learning approaches provide clinically actionable predictions that could inform treatments for colorectal cancer patients.

Desmoplastic Reaction, Immune Cell Response, and Prognosis in Colorectal Cancer.

Background: The relationships between tumor stromal features (such as desmoplastic reaction, myxoid stroma, and keloid-like collagen bundles) and immune cells in the colorectal carcinoma microenvironment have not yet been fully characterized. Methods: In 908 tumors with available tissue among 4,465 incident colorectal adenocarcinoma cases in two prospective cohort studies, we examined desmoplastic reaction, myxoid stroma, and keloid-like collagen bundles. We conducted multiplex immunofluorescence for T cells [CD3, CD4, CD8, CD45RO (PTPRC), and FOXP3] and for macrophages [CD68, CD86, IRF5, MAF, and MRC1 (CD206)]. We used the inverse probability weighting method and the 4,465 incident cancer cases to adjust for selection bias. Results: Immature desmoplastic reaction was associated with lower densities of intraepithelial CD3+CD8+CD45RO+ cells [multivariable odds ratio (OR) for the highest (vs. lowest) density category, 0.43; 95% confidence interval (CI), 0.29-0.62; Ptrend <0.0001] and stromal M1-like macrophages [the corresponding OR, 0.44; 95% CI, 0.28-0.70; Ptrend = 0.0011]. Similar relations were observed for myxoid stroma [intraepithelial CD3+CD8+CD45RO+ cells (Ptrend <0.0001) and stromal M1-like macrophages (Ptrend = 0.0007)] and for keloid-like collagen bundles (Ptrend <0.0001 for intraepithelial CD3+CD8+CD45RO+ cells). In colorectal cancer-specific survival analyses, multivariable-adjusted hazard ratios (with 95% confidence intervals) were 0.32 (0.23-0.44; Ptrend <0.0001) for mature (vs. immature) desmoplastic reaction, 0.25 (0.16-0.39; Ptrend <0.0001) for absent (vs. marked) myxoid stroma, and 0.12 (0.05-0.28; Ptrend <0.0001) for absent (vs. marked) keloid-like collagen bundles. Conclusions: Immature desmoplastic reaction and myxoid stroma were associated with lower densities of tumor intraepithelial memory cytotoxic T cells and stromal M1-like macrophages, likely reflecting interactions between tumor, immune, and stromal cells in the colorectal tumor microenvironment.

Prognostic role of inflammatory diets in colorectal cancer overall and in strata of tumor-infiltrating lymphocyte levels.

BACKGROUND: Certain dietary patterns can elicit systemic and intestinal inflammatory responses, which may influence adaptive anti-tumor immune responses and tumor behavior. We hypothesized that pro-inflammatory diets might be associated with higher colorectal cancer mortality and that the association might be stronger for tumors with lower immune responses. METHODS: We calculated an empirical dietary inflammatory pattern (EDIP) score in 2829 patients among 3988 incident rectal and colon carcinoma cases in the Nurses' Health Study and Health Professionals Follow-up Study. Using Cox proportional hazards regression analyses, we examined the prognostic association of EDIP scores and whether it might be modified by histopathologic immune reaction (in 1192 patients with available data). RESULTS: Higher EDIP scores after colorectal cancer diagnosis were associated with worse survival, with multivariable-adjusted hazard ratios (HRs) for the highest versus lowest tertile of 1.41 (95% confidence interval [CI]: 1.13-1.77; Ptrend = 0.003) for 5-year colorectal cancer-specific mortality and 1.44 (95% CI, 1.19-1.74; Ptrend = 0.0004) for 5-year all-cause mortality. The association of post-diagnosis EDIP scores with 5-year colorectal cancer-specific mortality differed by degrees of tumor-infiltrating lymphocytes (TIL; Pinteraction = .002) but not by three other lymphocytic reaction patterns. The multivariable-adjusted, 5-year colorectal cancer-specific mortality HRs for the highest versus lowest EDIP tertile were 1.59 (95% CI: 1.01-2.53) in TIL-absent/low cases and 0.48 (95% CI: 0.16-1.48) in TIL-intermediate/high cases. CONCLUSIONS: Pro-inflammatory diets after colorectal cancer diagnosis were associated with increased mortality, particularly in patients with absent or low TIL.

Spatial Organization and Prognostic Significance of NK and NKT-like Cells via Multimarker Analysis of the Colorectal Cancer Microenvironment.

Although tumor-infiltrating T cells hold a beneficial prognostic role in colorectal cancer, other lymphocytic populations are less characterized. We developed a multiplexed immunofluorescence assay coupled with digital image analysis and machine learning to identify natural killer (NK) cells (NCAM1+CD3-), natural killer T-like (NKT-like) cells (NCAM1+CD3+), and T cells (NCAM1-CD3+) within the PTPRC+ (CD45+) cell population and to measure their granzyme B (GZMB; cytotoxicity marker) and FCGR3A (CD16a; NK-cell maturity marker) expression. We evaluated immune cell densities and spatial configuration in 907 incident colorectal carcinoma cases within two prospective cohort studies. We found that T cells were approximately 100 times more abundant than NK and NKT-like cells. Overall, NK cells showed high GZMB expression and were located closer to tumor cells than T and NKT-like cells. In T and NKT-like cells, GZMB expression was enriched in cells in closer proximity to tumor cells. Higher densities of both T and NKT-like cells associated with longer cancer-specific survival, independent of potential confounders (P trend < 0.0007). Higher stromal GZMB+ and FCGR3A+ NK-cell densities associated with longer cancer-specific survival (P trend < 0.003). For T and NKT-like cells, greater proximity to tumor cells associated with longer cancer-specific survival (P trend < 0.0001). These findings indicate that cytotoxic NCAM1+CD3-GZMB+ NK cells and NCAM1+CD3+ NKT-like cells are relatively rare lymphocytic populations within the colorectal cancer microenvironment and show distinct spatial configuration and associations with patient outcome. The results highlight the utility of a quantitative multimarker assay for in situ, single-cell immune biomarker evaluation and underscore the importance of spatial context for tumor microenvironment characterization.

Elevated Hydrostatic Pressure Causes Retinal Degeneration Through Upregulating Lipocalin-2.

Elevation of intraocular pressure is a major risk factor for glaucoma development, which causes the loss of retinal ganglion cells (RGCs). Lipocalin 2 (Lcn2) is upregulated in glaucomatous retinae; however, whether Lcn2 is directly involved in glaucoma is debated. In this study, retinal explant cultures were subjected to increased water pressure using a two-chamber culture device, and Lcn2 protein levels were examined by immunoblotting. In situ TdT-mediated dUTP nick and labeling (TUNEL) and glial fibrillary acidic protein (GFAP) immunohistochemical assays were performed to assess apoptosis and gliosis, respectively. The neurotoxicity of Lcn2 in the retinal explant culture was determined with exogenous administration of recombinant Lcn2. The Lcn2 protein levels, percentage of TUNEL-positive cells, and GFAP-positive area were significantly higher in retinae cultured under 50 cm H2O pressure loads compared to those cultured under 20 cm H2O. We found that Lcn2 exhibited neurotoxicity in retinae at dose of 1 µg/ml. The negative effects of increased hydrostatic pressure were attenuated by the iron chelator deferoxamine. This is the first report demonstrating the direct upregulation of Lcn2 by elevating hydrostatic pressure. Modulating Lcn2 and iron levels may be a promising therapeutic approach for retinal degeneration.

TTF-1 and c-MYC-defined Phenotypes of Large Cell Neuroendocrine Carcinoma and Delta-like Protein 3 Expression for Treatment Selection.

The standard treatment regimen has not yet been established for advanced pulmonary large cell neuroendocrine carcinoma (LCNEC) because of its rarity. LCNEC can be subdivided into 2 mutually exclusive molecular subgroups: STK11/KEAP1 and TP53 mutated with high neuroendocrine expression and transcriptional profile of ASCL1high/DLL3high/NOTCHlow (non-small cell lung carcinoma, NSCLC-like) or RB1 and TP53 mutated with reduced neuroendocrine markers and transcriptional pattern of ASCL1low/DLL3low/NOTCHhigh (small cell lung cancer, SCLC-like). Model-based clustering shows that SCLC has subdivided into 2 major proteomic subsets defined by either TTF-1high/c-MYClow or TTF-1low/c-MYChigh, which may correspond to 2 mutually exclusive molecular subgroups: NSCLC-like or SCLC-like, respectively. We herein investigated whether TTF-1 and c-MYC could be applied to LCNEC to identify distinct subsets immunohistochemically and assessed DLL3 expression in these subsets. The protein expression profile may be useful to select patients for potential efficacy of targeted therapies including aurora kinase inhibitors for MYC alterations or anti-DLL3 antibody-drug conjugates. TTF-1 and c-MYC expression was mutually exclusive in 25 of 27 (93%) cases; TTF-1+/c-MYC- in 10, TTF-1-/c-MYC+ in 15, and TTF-1+/c-MYC+ in 2. DLL3 expression was seen in 15 of 27 cases (56%). All 12 TTF-1+ LCNEC cases were positive for DLL3. Three of 15 (20%) TTF-1-/c-MYC+ cases showed DLL3 positivity. LCNEC could be separated into 2 subsets proteomically defined by TTF-1 and c-MYC expression, which may be suitable to guide treatment selection including aurora kinase inhibitors for c-MYC+ cases. TTF-1 positivity can serve as a surrogate marker for DLL3, but caution is necessary as 20% of TTF-1- cases showed DLL3 positivity.

Association of PIK3CA mutation and PTEN loss with expression of CD274 (PD-L1) in colorectal carcinoma.

Immunotherapy targeting the CD274 (PD-L1)/PDCD1 (PD-1) immune checkpoint axis has emerged as a promising treatment strategy for various cancers. Experimental evidence suggests that phosphatidylinositol-4,5-bisphosphonate 3-kinase (PI3K) signaling may upregulate CD274 expression. Thus, we hypothesized that PIK3CA mutation, PTEN loss, or their combined status might be associated with CD274 overexpression in colorectal carcinoma. We assessed tumor CD274 and PTEN expression by immunohistochemistry and assessed PIK3CA mutation by pyrosequencing in 753 patients among 4,465 incident rectal and colon cancer cases that had occurred in two U.S.-wide prospective cohort studies. To adjust for potential confounders and selection bias due to tissue availability, inverse probability weighted multivariable ordinal logistic regression analyses used the 4,465 cases and tumoral data including microsatellite instability, CpG island methylator phenotype, KRAS and BRAF mutations. PIK3CA mutation and loss of PTEN expression were detected in 111 of 753 cases (15%) and 342 of 585 cases (58%), respectively. Tumor CD274 expression was negative in 306 (41%), low in 195 (26%), and high in 252 (33%) of 753 cases. PTEN loss was associated with CD274 overexpression [multivariable odds ratio (OR) 1.83; 95% confidence interval (CI), 1.22-2.75; P = .004]. PIK3CA mutation was statistically-insignificantly (P = .036 with the stringent alpha level of 0.005) associated with CD274 overexpression (multivariable OR, 1.54; 95% CI, 1.03-2.31). PIK3CA-mutated PTEN-lost tumors (n = 33) showed higher prevalence of CD274-positivity (82%) than PIK3CA-wild-type PTEN-lost tumors (n = 204; 70% CD274-positivity) and PTEN-expressed tumors (n = 147; 50% CD274-positivity) (P = .003). Our findings support the role of PI3K signaling in the CD274/PDCD1 pathway.

Urinary Cell Adhesion Molecule 1 Is a Novel Biomarker That Links Tubulointerstitial Damage to Glomerular Filtration Rates in Chronic Kidney Disease.

Cell adhesion molecule 1 (CADM1) is an immunoglobulin superfamily member strongly expressed on renal tubular epithelia in the urinary tract. Enzymatic cleavage of its ectodomain increases in chronic kidney disease (CKD), and is assumed to contribute to tubulointerstitial lesion formation. Because the cleaved ectodomain fragments are likely to be released into the urine, a sandwich enzyme-linked immunosorbent assay (ELISA) system for urinary CADM1 was developed using two anti-ectodomain antibodies. Urinary CADM1 concentrations in patients with CKD based on various forms of glomerulonephritis and nephropathy (n = 127) were measured. A total of 44 patients (35%) had elevated CADM1 concentrations over the normal upper limit (362 pg/mL), with a mean of 1,727 pg/mL. Renal biopsy specimens of all patients were pathologically scored for tubulointerstitial lesions using epithelial degeneration, interstitial inflammation, and fibrosis. There were no correlations between urinary CADM1 concentrations and pathological scores or any widely used renal markers, including glomerular filtration rate (GFR), but there was a weak inverse correlation between pathological scores and GFR (R2 = 0.292). Notably, this correlation gradually increased in patients with increasing CADM1 concentrations, and reached a maximum R 2 (0.899) at a cutoff of 1,569 pg/mL. The results of this study suggest that urinary CADM1 is a useful marker indicating tubulointerstitial damage from elevated GFR levels in CKD.

Modest Static Pressure Suppresses Columnar Epithelial Cell Growth in Association with Cell Shape and Cytoskeletal Modifications.

Intraluminal pressure elevation can cause degenerative disorders, such as ileus and hydronephrosis, and the threshold is fairly low and constant, 20-30 cm H2O. We previously devised a novel two-chamber culture system subjecting cells cultured on a semipermeable membrane to increased culture medium height (water pressure up to 60 cm H2O). Here, we sought to determine how a continuous pressure load of ~30 cm H2O affects proliferating epithelial cells with special interest in the link with cell morphology. We cultured several different cell lines using the low static pressure-loadable two-chamber system, and examined cell growth, cell cycle, and cell morphology. Madin-Darby canine kidney (MDCK) columnar epithelial cells were growth-suppressed in a manner dependent on static water pressure ranging from 2 to 50 cm H2O, without cell cycle arrest at any specific phase. Two other types of columnar epithelial cells exhibited similar phenotypes. By contrast, spherical epithelial and mesenchymal cells were not growth-suppressed, even at 50 cm H2O. Phalloidin staining revealed that 50 cm H2O pressure load vertically flattened and laterally widened columnar epithelial cells and made actin fiber distribution sparse, without affecting total phalloidin intensity per cell. When the mucosal protectant irsogladine maleate (100 nM) was added to 50-cm-high culture medium, MDCK cells were reduced in volume and their doubling time shortened. Cell proliferation and morphology are known to be regulated by the Hippo signaling pathway. A pressure load of 50 cm H2O enhanced serine-127 phosphorylation and cytoplasmic retention of YAP, the major constituent of this pathway, suggesting that Hippo pathway was involved in the pressure-induced cell growth suppression. RNA sequencing of MDCK cells showed that a 50 cm H2O pressure load upregulated keratin 14, an intermediate filament, 12-fold. This upregulation was confirmed at the protein level by immunofluorescence, suggesting a role in cytoskeletal reinforcement. These results provide evidence that cell morphology and the cytoskeleton are closely linked to cell growth. Pathological intraluminal pressure elevation may cause mucosal degeneration by acting directly on this linkage and the Hippo pathway.