Daam2 phosphorylation by CK2α negatively regulates Wnt activity during white matter development and injury.

Wnt signaling plays an essential role in developmental and regenerative myelination in the central nervous system. The Wnt signaling pathway is composed of multiple regulatory layers; thus, how these processes are coordinated to orchestrate oligodendrocyte (OL) development remains unclear. Here, we show CK2α, a Wnt/ß-catenin signaling Ser/Thr kinase, phosphorylates Daam2, inhibiting its function and Wnt activity during OL development. Intriguingly, we found Daam2 phosphorylation differentially impacts distinct stages of OL development, accelerating early differentiation followed by decelerating maturation and myelination. Application toward white matter injury revealed CK2α-mediated Daam2 phosphorylation plays a protective role for developmental and behavioral recovery after neonatal hypoxia, while promoting myelin repair following adult demyelination. Together, our findings identify a unique regulatory node in the Wnt pathway that regulates OL development via protein phosphorylation-induced signaling complex instability and highlights a new biological mechanism for myelin restoration.

SCAMP4 enhances the senescent cell secretome.

The senescence-associated secretory phenotype (SASP) is a major trait of senescent cells, but the molecular regulators of SASP factor secretion are poorly understood. Mass spectrometry analysis revealed that secretory carrier membrane protein 4 (SCAMP4) levels were strikingly elevated on the surface of senescent cells compared with proliferating cells. Interestingly, silencing SCAMP4 in senescent fibroblasts reduced the secretion of SASP factors, including interleukin 6 (IL6), IL8, growth differentiation factor 15 (GDF-15), C-X-C motif chemokine ligand 1 (CXCL1), and IL7, while, conversely, SCAMP4 overexpression in proliferating fibroblasts increased SASP factor secretion. Our results indicate that SCAMP4 accumulates on the surface of senescent cells, promotes SASP factor secretion, and critically enhances the SASP phenotype.

Spin Hall-induced bilinear magnetoelectric resistance.

Magnetoresistance is a fundamental transport phenomenon that is essential for reading the magnetic states for various information storage, innovative computing and sensor devices. Recent studies have expanded the scope of magnetoresistances to the nonlinear regime, such as a bilinear magnetoelectric resistance (BMER), which is proportional to both electric field and magnetic field. Here we demonstrate that the BMER is a general phenomenon that arises even in three-dimensional systems without explicit momentum-space spin textures. Our theory suggests that the spin Hall effect enables the BMER provided that the magnitudes of spin accumulation at the top and bottom interfaces are not identical. The sign of the BMER follows the sign of the spin Hall effect of heavy metals, thereby evidencing that the BMER originates from the bulk spin Hall effect. Our observation suggests that the BMER serves as a general nonlinear transport characteristic in three-dimensional systems, especially playing a crucial role in antiferromagnetic spintronics.

Field-free switching of perpendicular magnetization by two-dimensional PtTe2/WTe2 van der Waals heterostructures with high spin Hall conductivity.

The key challenge of spin-orbit torque applications lies in exploring an excellent spin source capable of generating out-of-plane spins while exhibiting high spin Hall conductivity. Here we combine PtTe2 for high spin conductivity and WTe2 for low crystal symmetry to satisfy the above requirements. The PtTe2/WTe2 bilayers exhibit a high in-plane spin Hall conductivity σs,y ≈ 2.32 × 105 × h/2e Ω-1 m-1 and out-of-plane spin Hall conductivity σs,z ≈ 0.25 × 105 × h/2e Ω-1 m-1, where h is the reduced Planck's constant and e is the value of the elementary charge. The out-of-plane spins in PtTe2/WTe2 bilayers enable the deterministic switching of perpendicular magnetization at room temperature without magnetic fields, and the power consumption is 67 times smaller than that of the Pt control case. The high out-of-plane spin Hall conductivity is attributed to the conversion from in-plane spin to out-of-plane spin, induced by the crystal asymmetry of WTe2. Our work establishes a low-power perpendicular magnetization manipulation based on wafer-scale two-dimensional van der Waals heterostructures.

Characterization of a new CCCTC-binding factor binding site as a dual regulator of Epstein-Barr virus latent infection.

Distinct viral gene expression characterizes Epstein-Barr virus (EBV) infection in EBV-producing marmoset B-cell (B95-8) and EBV-associated gastric carcinoma (SNU719) cell lines. CCCTC-binding factor (CTCF) is a structural chromatin factor that coordinates chromatin interactions in the EBV genome. Chromatin immunoprecipitation followed by sequencing against CTCF revealed 16 CTCF binding sites in the B95-8 and SNU719 EBV genomes. The biological function of one CTCF binding site (S13 locus) located on the BamHI A right transcript (BART) miRNA promoter was elucidated experimentally. Microscale thermophoresis assay showed that CTCF binds more readily to the stable form than the mutant form of the S13 locus. EBV BART miRNA clusters encode 22 miRNAs, whose roles are implicated in EBV-related cancer pathogenesis. The B95-8 EBV genome lacks a 11.8-kb EcoRI C fragment, whereas the SNU719 EBV genome is full-length. ChIP-PCR assay revealed that CTCF, RNA polymerase II, H3K4me3 histone, and H3K9me3 histone were more enriched at S13 and S16 (167-kb) loci in B95-8 than in the SNU719 EBV genome. 4C-Seq and 3C-PCR assays using B95-8 and SNU719 cells showed that the S13 locus was associated with overall EBV genomic loci including 3-kb and 167-kb region in both EBV genomes. We generated mutations in the S13 locus in bacmids with or without the 11.8-kb BART transcript unit (BART(+/-)). The S13 mutation upregulated BART miRNA expression, weakened EBV latency, and reduced EBV infectivity in the presence of EcoRI C fragment. Another 3C-PCR assay using four types of BART(+/-)·S13(wild-type(Wt)/mutant(Mt)) HEK293-EBV cells revealed that the S13 mutation decreased DNA associations between the 167-kb region and 3-kb in the EBV genome. Based on these results, CTCF bound to the S13 locus along with the 11.8-kb EcoRI C fragment is suggested to form an EBV 3-dimensional DNA loop for coordinated EBV BART miRNA expression and infectivity.

Emergence of Stable Meron Quartets in Twisted Magnets.

The investigation of twist engineering in easy-axis magnetic systems has revealed remarkable potential for generating topological spin textures. Implementing twist engineering in easy-plane magnets, we introduce a novel approach to achieving fractional topological spin textures, such as merons. Through atomistic spin simulations on twisted bilayer magnets, we demonstrate the formation of a stable double Meron pair, which we refer to as the "Meron Quartet" (MQ). Unlike a single pair, the merons within the MQ exhibit exceptional stability against pair annihilation due to the protective localization mechanism induced by the twist that prevents collision of the Meron cores. Furthermore, we showcase that the stability of the MQ can be enhanced by adjusting the twist angle, resulting in an increased resistance to external perturbations such as external magnetic fields. Our findings highlight the twisted magnet as a promising platform for achieving merons as stable magnetic quasiparticles in van der Waals magnets.

Identification of senescent cell surface targetable protein DPP4.

Senescent cell accumulation in aging tissues is linked to age-associated diseases and declining function, prompting efforts to eliminate them. Mass spectrometry analysis revealed that DPP4 (dipeptidyl peptidase 4) was selectively expressed on the surface of senescent, but not proliferating, human diploid fibroblasts. Importantly, the differential presence of DPP4 allowed flow cytometry-mediated isolation of senescent cells using anti-DPP4 antibodies. Moreover, antibody-dependent cell-mediated cytotoxicity (ADCC) assays revealed that the cell surface DPP4 preferentially sensitized senescent, but not dividing, fibroblasts to cytotoxicity by natural killer cells. In sum, the selective expression of DPP4 on the surface of senescent cells enables their preferential elimination.

Prognostic Effect of Tertiary Lymphoid Structures in Epstein-Barr Virus-Associated Gastric Carcinomas Measured by Digital Image Analysis.

Epstein-Barr virus-associated gastric carcinoma (EBVaGC) is characterized by prominent tumor-infiltrating lymphocytes (TILs) and has a favorable prognosis. Tertiary lymphoid structures (TLS), characterized by ectopic aggregated lymphocytes with high-endothelial venules (HEV), are associated with favorable outcomes in various solid tumors. We hypothesized that EBVaGC, characterized by intense TILs, may be closely associated with TLS or HEV. To test this hypothesis, we digitally analyzed the TLS, HEV, and TILs in 73 surgically resected advanced EBVaGCs. For HEV, dual MECA-79 and CD31 dual immunohistochemistry were performed, and the ectopic expression of MECA-79 in tumor cells was measured. In 73 patients with EBVaGC, a high-TLS ratio was found in 29 (39.7%) cases, high-tumor-associated HEV density in 44 (60.3%) cases, and high-CD8+ TIL density in 38 (52.1%) cases. Ectopic tumor expression of MECA-79 was observed in 36 patients (49.3%) cases. A low-TLS ratio and tumor-associated HEV density were significantly associated with lymph node metastasis (P = .005 and .042, respectively). Ectopic MECA-79 expression was significantly associated with lymph node metastasis (P = .003). Patients with a low-TLS ratio (P = .038), low-HEV density (P = .042), and ectopic tumor MECA-79 expression (P = .032) had significantly worse prognoses. In conclusion, TLS ratio and HEV density affect the survival of patients with EBVaGC and may be related to the immune response that interrupts lymph node metastasis.

Single-cell transcriptome analysis reveals subtype-specific clonal evolution and microenvironmental changes in liver metastasis of pancreatic adenocarcinoma and their clinical implications.

BACKGROUND: Intratumoral heterogeneity (ITH) and tumor microenvironment (TME) of pancreatic ductal adenocarcinoma (PDAC) play important roles in tumor evolution and patient outcomes. However, the precise characterization of diverse cell populations and their crosstalk associated with PDAC progression and metastasis is still challenging. METHODS: We performed single-cell RNA sequencing (scRNA-seq) of treatment-naïve primary PDAC samples with and without paired liver metastasis samples to understand the interplay between ITH and TME in the PDAC evolution and its clinical associations. RESULTS: scRNA-seq analysis revealed that even a small proportion (22%) of basal-like malignant ductal cells could lead to poor chemotherapy response and patient survival and that epithelial-mesenchymal transition programs were largely subtype-specific. The clonal homogeneity significantly increased with more prevalent and pronounced copy number gains of oncogenes, such as KRAS and ETV1, and losses of tumor suppressor genes, such as SMAD2 and MAP2K4, along PDAC progression and metastasis. Moreover, diverse immune cell populations, including naïve SELLhi regulatory T cells (Tregs) and activated TIGIThi Tregs, contributed to shaping immunosuppressive TMEs of PDAC through cellular interactions with malignant ductal cells in PDAC evolution. Importantly, the proportion of basal-like ductal cells negatively correlated with that of immunoreactive cell populations, such as cytotoxic T cells, but positively correlated with that of immunosuppressive cell populations, such as Tregs. CONCLUSION: We uncover that the proportion of basal-like subtype is a key determinant for chemotherapy response and patient outcome, and that PDAC clonally evolves with subtype-specific dosage changes of cancer-associated genes by forming immunosuppressive microenvironments in its progression and metastasis.

Effect of YC-1102 on the Improvement of Obesity in High-Fat Diet-Induced Obese Mice.

Obesity is one of the major risk factors for metabolic diseases worldwide. This study examined the effects of YC-1102, an extract derived from the roots of Rosa multiflora, on 3T3-L1 preadipocytes and high-fat diet (HFD)-induced obese mice. In vivo experiments involved the oral administration of YC-1102 (100, 150, and 200 mg/kg body weight) daily to mice for eight weeks. YC-1102 was found to downregulate the expressions of PPARγ and C/EBPα during adipogenesis, inhibiting adipocyte differentiation and upregulating the expression of PGC-1α for energy metabolism to enhance mitochondrial biogenesis and fatty acid oxidation. It has been shown that daily administration of YC-1102 to mice receiving a HFD prevented an increase in body weight and the accumulation of body fat. YC-1102 administration also reduced TG, TC, and LDL cholesterol levels, as well as glucose and leptin levels, and increased adiponectin levels, thus effectively inhibiting the metabolism of lipids. YC-1102-treated mice showed significant reductions in the mRNA expression of PPARγ and C/EBPα. The levels of PGC-1α involved in energy metabolism increased significantly in the YC-1102-treated mice when compared to the HFD-treated mice. According to the findings of this study, YC-1102 has a dual mechanism that reduces transcription factors that promote the differentiation of adipocytes and increases transcription factors that promote energy consumption.

Chromatin accessibility analysis and architectural profiling of human kidneys reveal key cell types and a regulator of diabetic kidney disease.

Diabetes is the leading cause of kidney disease that progresses to kidney failure. However, the key molecular and cellular pathways involved in diabetic kidney disease (DKD) pathogenesis are largely unknown. Here, we performed a comparative analysis of adult human kidneys by examining cell type-specific chromatin accessibility by single-nucleus ATAC-seq (snATAC-seq) and analyzing three-dimensional chromatin architecture via high-throughput chromosome conformation capture (Hi-C method) of paired samples. We mapped the cell type-specific and DKD-specific open chromatin landscape and found that genetic variants associated with kidney diseases were significantly enriched in the proximal tubule- (PT) and injured PT-specific open chromatin regions in samples from patients with DKD. BACH1 was identified as a core transcription factor of injured PT cells; its binding target genes were highly associated with fibrosis and inflammation, which were also key features of injured PT cells. Additionally, Hi-C analysis revealed global chromatin architectural changes in DKD, accompanied by changes in local open chromatin patterns. Combining the snATAC-seq and Hi-C data identified direct target genes of BACH1, and indicated that BACH1 binding regions showed increased chromatin contact frequency with promoters of their target genes in DKD. Thus, our multi-omics analysis revealed BACH1 target genes in injured PTs and highlighted the role of BACH1 as a novel regulator of tubular inflammation and fibrosis.

GNUV201, a novel human/mouse cross-reactive and low pH-selective anti-PD-1 monoclonal antibody for cancer immunotherapy.

BACKGROUND: Several PD-1 antibodies approved as anti-cancer therapies work by blocking the interaction of PD-1 with its ligand PD-L1, thus restoring anti-cancer T cell activities. These PD-1 antibodies lack inter-species cross-reactivity, necessitating surrogate antibodies for preclinical studies, which may limit the predictability and translatability of the studies. RESULTS: To overcome this limitation, we have developed an inter-species cross-reactive PD-1 antibody, GNUV201, by utilizing an enhanced diversity mouse platform (SHINE MOUSE™). GNUV201 equally binds to human PD-1 and mouse PD-1, equally inhibits the binding of human PD-1/PD-L1 and mouse PD-1/PD-L1, and effectively suppresses tumor growth in syngeneic mouse models. The epitope of GNUV201 mapped to the "FG loop" of hPD-1, distinct from those of Keytruda® ("C'D loop") and Opdivo® (N-term). Notably, the structural feature where the protruding epitope loop fits into GNUV201's binding pocket supports the enhanced binding affinity due to slower dissociation (8.7 times slower than Keytruda®). Furthermore, GNUV201 shows a stronger binding affinity at pH 6.0 (5.6 times strong than at pH 7.4), which mimics the hypoxic and acidic tumor microenvironment (TME). This phenomenon is not observed with marketed antibodies (Keytruda®, Opdivo®), implying that GNUV201 achieves more selective binding to and better occupancy on PD-1 in the TME. CONCLUSIONS: In summary, GNUV201 exhibited enhanced affinity for PD-1 with slow dissociation and preferential binding in TME-mimicking low pH. Human/monkey/mouse inter-species cross-reactivity of GNUV201 could enable more predictable and translatable efficacy and toxicity preclinical studies. These results suggest that GNUV201 could be an ideal antibody candidate for anti-cancer drug development.

Establishment of a patient-specific avatar organoid model derived from EUS-guided fine-needle biopsy for timely clinical application in pancreatic ductal adenocarcinoma (with video).

BACKGROUND AND AIMS: Pancreatic ductal adenocarcinoma (PDAC) has the worst survival rate among tumors. At the time of diagnosis, more than 80% of PDACs are considered to be surgically unresectable, and there is an unmet need for treatment options in these inoperable PDACs. This study aimed to establish a patient-derived organoid (PDO) platform from EUS-guided fine-needle biopsy (EUS-FNB) collected at diagnosis and to determine its clinical applicability for the timely treatment of unresectable PDAC. METHODS: Patients with suspected PDAC were prospectively enrolled at the Samsung Medical Center from 2015 to 2019. PDAC tissues were acquired by means of EUS-FNB to establish PDAC PDOs, which were comprehensively analyzed for histology, genomic sequencing, and high-throughput screening (HTS) drug sensitivity test. RESULTS: PDAC PDOs were established with a success rate of 83.2% (94/113). It took approximately 3 weeks from acquiring minimal EUS-FNB specimens to generating sufficient PDAC PDOs for the simultaneous HTS drug sensitivity test and genomic sequencing. The high concordance between PDAC tissues and matched PDOs was confirmed, and whole-exome sequencing revealed the increased detection of genetic alterations in PDOs compared with EUS-FNB tissues. The HTS drug sensitivity test showed clinical correlation between the ex vivo PDO response and the actual chemotherapeutic response of the study patients in the real world (13 out of 15 cases). In addition, whole-transcriptome sequencing identified candidate genes associated with nab-paclitaxel resistance, such as ITGB7, ANPEP, and ST3GAL1. CONCLUSIONS: This PDAC PDO platform allows several therapeutic drugs to be tested within a short time window and opens the possibility for timely personalized medicine as a "patient avatar model" in clinical practice.

Efficacy and safety of dapagliflozin add-on to evogliptin plus metformin therapy in patients with type 2 diabetes: A randomized, double-blind, placebo-controlled study.

AIM: To evaluate the efficacy and safety of dapagliflozin versus placebo as an add-on in patients with type 2 diabetes who did not achieve adequate glycaemic control with evogliptin and metformin combination. PATIENTS AND METHODS: In this multicentre, randomized, double-blind, placebo-controlled Phase 3 trial, patients with glycated haemoglobin (HbA1c) levels ≥7.0% (≥53 mmol/mol) and ≤10.5% (≤91 mmol/mol) who had received stable-dose metformin (≥1000 mg) and evogliptin (5 mg) for at least 8 weeks were randomized to receive dapagliflozin 10 mg or placebo once daily for 24 weeks. Participants continued treatment with metformin and evogliptin. The primary endpoint was change in HbA1c level after 24 weeks of treatment from baseline level. RESULTS: In total, 198 patients were randomized, and 195 patients were included in the efficacy analyses (dapagliflozin: 96, placebo: 99). At Week 24, dapagliflozin significantly reduced HbA1c levels. The least squares mean difference in HbA1c level change from baseline after 24 weeks of treatment was -0.70% (-7.7 mmol/mol) (p < 0.0001). The proportion of participants achieving HbA1c <7.0% (≥53 mmol/mol) was higher in the dapagliflozin group than in the placebo group. Compared to placebo, dapagliflozin significantly reduced fasting plasma glucose, mean daily glucose, 2-h postprandial plasma glucose, fasting insulin, uric acid and gamma-glutamyl transferase levels, homeostatic model assessment for insulin resistance index, body weight, hepatic steatosis index, and albuminuria. Adiponectin level significantly increased from baseline level after 24 weeks of dapagliflozin treatment. Adverse event rates were similar in the two groups. CONCLUSION: Dapagliflozin add-on to evogliptin plus metformin improved glycaemic control and was well tolerated by the target patients.

Dual add-on therapy of gemigliptin and dapagliflozin in patients with type 2 diabetes inadequately controlled with metformin alone: The SOLUTION 2 study.

AIM: To evaluate the efficacy and safety of gemigliptin and dapagliflozin dual add-on therapy (GEMI + DAPA) to metformin in type 2 diabetes (T2D) patients who had inadequate glycaemic control on metformin alone, compared with a single add-on of either gemigliptin (GEMI) or dapagliflozin (DAPA) to metformin. MATERIALS AND METHODS: In this randomized, double-blind, double-dummy, active-controlled, parallel-group, phase 3 study, 469 T2D patients treated with a stable dose of metformin for 8 weeks or longer were randomized to receive GEMI + DAPA (n = 157) and either GEMI (n = 156) or DAPA (n = 156). The primary endpoint was change in HbA1c levels from baseline at week 24. RESULTS: Baseline characteristics including body mass index and T2D duration were similar among groups. At week 24, the least square mean changes in HbA1c from baseline were -1.34% with GEMI + DAPA, -0.90% with GEMI (difference between GEMI + DAPA vs. GEMI -0.44% [95% confidence interval {CI}: -0.58% to -0.31%], P < .01) and -0.78% with DAPA (difference between GEMI + DAPA vs. DAPA -0.56% [95% CI: -0.69% to -0.42%], P < .01). Both upper CIs were less than 0, demonstrating the superiority of GEMI + DAPA for lowering HbA1c. The rates of responders achieving HbA1c less than 7% and less than 6.5% were greater with GEMI + DAPA (84.9%, 56.6%) than with GEMI (55.3%, 32.2%) and DAPA (49.3%, 15.3%). The incidence rate of adverse events was similar across groups, with low incidence rates of hypoglycaemia, urinary tract infection and genital infection. CONCLUSIONS: These results suggest that the addition of GEMI + DAPA to metformin as triple combination therapy was effective, safe and well-tolerated, especially for T2D patients who experienced poor glycaemic control on metformin alone.

Carbon dioxide valorization into resveratrol via lithoautotrophic fermentation using engineered Cupriavidus necator H16.

BACKGROUND: Industrial biomanufacturing of value-added products using CO2 as a carbon source is considered more sustainable, cost-effective and resource-efficient than using common carbohydrate feedstocks. Cupriavidus necator H16 is a representative H2-oxidizing lithoautotrophic bacterium that can be utilized to valorize CO2 into valuable chemicals and has recently gained much attention as a promising platform host for versatile C1-based biomanufacturing. Since this microbial platform is genetically tractable and has a high-flux carbon storage pathway, it has been engineered to produce a variety of valuable compounds from renewable carbon sources. In this study, the bacterium was engineered to produce resveratrol autotrophically using an artificial phenylpropanoid pathway. RESULTS: The heterologous genes involved in the resveratrol biosynthetic pathway-tyrosine ammonia lyase (TAL), 4-coumaroyl CoA ligase (4CL), and stilbene synthase (STS) -were implemented in C. necator H16. The overexpression of acetyl-CoA carboxylase (ACC), disruption of the PHB synthetic pathway, and an increase in the copy number of STS genes enhanced resveratrol production. In particular, the increased copies of VvSTS derived from Vitis vinifera resulted a 2-fold improvement in resveratrol synthesis from fructose. The final engineered CR-5 strain produced 1.9 mg/L of resveratrol from CO2 and tyrosine via lithoautotrophic fermentation. CONCLUSIONS: To the best of our knowledge, this study is the first to describe the valorization of CO2 into polyphenolic compounds by engineering a phenylpropanoid pathway using the lithoautotrophic bacterium C. necator H16, demonstrating the potential of this strain a platform for sustainable chemical production.

Identification of maximal tumor size associated with negligible lymph node metastasis for endoscopic submucosal dissection of undifferentiated-type early gastric cancer.

BACKGROUND AND AIMS: When treating undifferentiated-type early gastric cancer (UD-EGC) that is limited to the mucosa (clinically T1a), endoscopic submucosal dissection (ESD) can be considered if the tumor is 2 cm or less and is not ulcerated. However, there is insufficient evidence to determine the relationships between tumor size and oncological safety of ESD in UD-EGC. METHODS: The pathology reports of Korean patients who were diagnosed with UD-EGC (n = 5286) were retrospectively reviewed. The cumulative incidence of lymph node metastasis (LNM) according to tumor size was evaluated in subgroups. The tumor-size cut-off was identified as the upper limit of the 95% confidence interval (CI) of cumulative LNM incidence that did not exceed 1.0%. RESULTS: We identified 1516 patients with non-ulcerated T1a tumors ≤2 cm in size. Among patients without lymphatic invasion, 1.5% (95% CI 0.91-2.16%) had LNM. In patients with poorly differentiated tubular adenocarcinoma (PD), LNM increased from 0 to 0.74% based on a tumor size of 1.0 cm. Regardless of tumor size, smaller percentages of undifferentiated-type (UD) and poorly cohesive carcinoma (PCC) patients experienced LNM than did those with PD. In non-ulcerated mucosal cancer without lymphatic invasion and tumor size ≤0.9 cm, no LNM was observed in patients with UD (95% CI 0-0.53%), PCC (95% CI 0-0.59%), or PD (95% CI 0-0.86%) histologic type. CONCLUSION: In patients diagnosed with non-ulcerated T1a UD-EGC, ESD can be performed if the tumor size is 0.9 cm or less, regardless of histologic type.

PIK3CA mutation subtype delineates distinct immune profiles in gastric carcinoma.

PIK3CA mutations in cancer regulate tumour immunogenicity. Given that PIK3CA mutation subtypes influence therapeutic responses to AKT inhibitor and that H1047R mutation confers selective growth advantages after immunotherapy, we hypothesised that immune phenotypes may depend on PIK3CA mutation subtypes. We investigated 133 gastric cancers (GCs) harbouring PIK3CA mutation [21 E542K (15.8%), 36 E545X (27.1%), 26 H1047X (19.5%), and 46 others (34.6%)]. Four patients (3.0%) had a combination of mutations (E542K + E545K in 3 patients and E545K + H1047R in 1 patient). Epstein-Barr virus (EBV) and microsatellite instability (MSI) status, PD-L1 (programmed death-ligand 1) combined positive score (CPS), and stromal tumour-infiltrating lymphocytes (TILs) were assessed. Concurrent genomic alterations, GeoMx digital spatial profiling (DSP), and OPAL multiplex immunohistochemistry (mIHC) were analysed, and correlation between the two assays was investigated. Of the 133 PIK3CA-mutant (PIK3CAm ) GCs, MSI-high GC was significantly frequent in the H1047X mutation subtype (p = 0.005), while EBV positivity did not affect the mutation subtypes. There was no significant survival difference between the E542K, E545X, and H1047X subgroups. However, in the subgroup analysis for EBV-positive GC, H1047Xm GC showed a trend towards shorter survival than E542K and E545Xm GC (p = 0.090 and 0.062). With DSP analysis, H1047Xm GC showed elevated VISTA (p = 0.0003), granzyme B (p < 0.0001), CD4 (p = 0.0001), and CD45 (p < 0.0001) expression compared with the E542Km or E545Xm GC subgroups, and only VISTA expression remained significant (p < 0.0001) using OPAL mIHC. DSP and OPAL analyses showed a moderate correlation of CD4 (ρ = 0.42, p = 0.004) and CD8 (ρ = 0.62, p < 0.001) expression levels in a comparison of six antibodies. Immune-related protein expression levels were evident when classified by the three PIK3CA hotspot mutations, and H1047Xm GC showed the highest immune-related protein expression compared with E542Km or E545Xm GC. Our results demonstrated distinct immune profiles in GC with PIK3CA hotspot mutations using GeoMx DSP and OPAL mIHC, and there was a correlation between the two multiplex platforms. © 2023 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.

Associations between short-term exposure to air pollution and thyroid function in a representative sample of the Korean population.

BACKGROUND: Disruption of thyroid function can profoundly affect various organ systems. However, studies on the association between air pollution and thyroid function are relatively scarce and most studies have focused on the long-term effects of air pollution among pregnant women. OBJECTIVES: This study aimed to explore the associations between short-term exposure to air pollution and thyroid function in the general population. METHODS: Data from the Korea National Health and Nutrition Examination Survey (2013-2015) were analyzed (n = 5,626). Air pollution concentrations in residential addresses were estimated using Community Multiscale Air Quality models. The moving averages of air pollution over 7 days were set as exposure variables through exploratory analyses. Linear regression and quantile g-computation models were constructed to assess the effects of individual air pollutants and air pollution mixture, respectively. RESULTS: A 10-ppb increase in NO2 (18.8-µg/m3 increase) and CO (11.5-µg/m3 increase) was associated with 2.43% [95% confidence interval (CI): 0.42, 4.48] and 0.19% (95% CI: 0.01, 0.36) higher thyroid-stimulating hormone (TSH) levels, respectively. A 10-µg/m3 increase in PM2.5 and a 10-ppb increase in O3 (19.6-µg/m3 increment) were associated with 0.87% (95% CI: 1.47, -0.27) and 0.59% (95% CI: 1.18, -0.001) lower free thyroxine (fT4) levels, respectively. A simultaneous quartile increase in PM2.5, NO2, O3, and CO levels was associated with lower fT4 but not TSH levels. CONCLUSIONS: As the subtle changes in thyroid function can affect various organ systems, the present results may have substantial public health implications despite the relatively modest effect sizes. Because this was a cross-sectional study, it is necessary to conduct further experimental or repeated-measures studies to consolidate the current results.

Catabolism of 2-keto-3-deoxy-galactonate and the production of its enantiomers.

2-Keto-3-deoxy-galactonate (KDGal) serves as a pivotal metabolic intermediate within both the fungal D-galacturonate pathway, which is integral to pectin catabolism, and the bacterial DeLey-Doudoroff pathway for D-galactose catabolism. The presence of KDGal enantiomers, L-KDGal and D-KDGal, varies across these pathways. Fungal pathways generate L-KDGal through the reduction and dehydration of D-galacturonate, whereas bacterial pathways produce D-KDGal through the oxidation and dehydration of D-galactose. Two distinct catabolic routes further metabolize KDGal: a nonphosphorolytic pathway that employs aldolase and a phosphorolytic pathway involving kinase and aldolase. Recent findings have revealed that L-KDGal, identified in the bacterial catabolism of 3,6-anhydro-L-galactose, a major component of red seaweeds, is also catabolized by Escherichia coli, which is traditionally known to be catabolized by specific fungal species, such as Trichoderma reesei. Furthermore, the potential industrial applications of KDGal and its derivatives, such as pyruvate and D- and L-glyceraldehyde, are underscored by their significant biological functions. This review comprehensively outlines the catabolism of L-KDGal and D-KDGal across different biological systems, highlights stereospecific methods for discriminating between enantiomers, and explores industrial application prospects for producing KDGal enantiomers. KEY POINTS: • KDGal is a metabolic intermediate in fungal and bacterial pathways • Stereospecific enzymes can be used to identify the enantiomeric nature of KDGal • KDGal can be used to induce pectin catabolism or produce functional materials.