Death receptors 4/5 mediate tumour sensitivity to natural killer cell-mediated cytotoxicity in mismatch repair deficient colorectal cancer.

BACKGROUND: Identifying the target of natural killer (NK) cells in colorectal cancer (CRC) is critical for optimising the clinical use of NK cell-mediated immunotherapy. Mismatch repair deficiency (dMMR) is associated with high immune cell infiltration and MHC Class I defects. Whether dMMR CRC responses to NK cell therapy remains unclear. METHODS: MLH1, DR4, and DR5 knockout cell lines were established using CRISPR-Cas9 system. NK92-MI or NK cell isolated from BABL/C mice were used as effector cells against tumour cells. Inflammatory cytokines secretion by CRC cells was assessed via cytokine analysis. NK-cell-deficient/proficient animal models were used to validate the NK cell sensitivity. RESULTS: We observed that dMMR CRC cells were more sensitive to NK cell-mediated cytotoxicity than were mismatch-repair-proficient (pMMR) CRC cells. In dMMR CRC, Death receptor (DR)4/5 was upregulated and mediated sensitivity to NK cell-mediated cytotoxicity. DR4/5-mediated secretion of interleukin -12 sustained NK cell viability in dMMR CRC. NK cell depletion induced dMMR CRC tumour growth, and NK cell transfer inhibited lung metastasis of dMMR CRC with DR4/5 expression in vivo. TP53 upregulated DR4/DR5 expression in dMMR CRC. CONCLUSIONS: dMMR associated with increased sensitivity to NK cell-mediated cytotoxicity in CRC. DR4/DR5 sensitise dMMR CRC to NK cell-mediated cytotoxicity.

Enantiomer-Specific Colorimetric Tandem Assays for Salivary d-Alanine Associated with Gastric Cancer.

Salivary d-alanine (d-Ala) and d-proline (d-Pro) are of concern for their potential in the noninvasive diagnosis of gastric cancer (GC). Most reports have succeeded in determining the total concentration of d-Ala and d-Pro. However, for personalized diagnosis and better elucidation of the underlying specific correlation of d-Ala (or d-Pro) with GC, it is desirable to determine the specific concentration of d-Ala or d-Pro. Herein, we propose an enantiomer-specific tandem assay of d-Ala based on the colorimetric reaction between 2,4-dinitrophenylhydrazine and pyruvic acid generated from the deamination of d-Ala catalyzed by d-amino acid oxidase, which is easily distinguished from l-form amino acids, d-Pro, and many other species. A linear concentration range is established from 20 to 400 µmol/L with a limit of detection of 1.01 µmol/L. Real saliva sample tests reveal that the levels of d-Ala in GC cases are remarkably higher than those in healthy individuals, which offers a simple and low-cost strategy for GC diagnosis. Simultaneously, the total concentrations of d-Ala and d-Pro in saliva are determined. Hence, the concentration of d-Pro and the proportion of d-Ala could be calculated, which further provides more molecule- and individual-specific information. This research may offer a convenient method for noninvasive diagnosis of GC and pave a new route to explore the potentials of rare d-form amino acids in disease diagnosis and treatment.

CD47-targeted immunotherapy unleashes antitumour immunity in Epstein-Barr virus-associated gastric cancer.

The aims of this study were to enhance the antitumour immunity in Epstein-Barr virus-associated gastric cancer (EBVaGC). We performed RNA-seq analysis to compare the differential expression genes between EBVaGC and EBV-negative gastric cancer (EBVnGC) patients. The expression levels of CD68, CD163 and CD47 were analyzed by immunohistochemistry. Different subsets of macrophages were investigated by a coincubation model. The effects of CD47 blockade were also detected. The expression levels of CD68, CD163 and CD47 were significantly higher in EBVaGC, and were associated with poor prognoses. Macrophages coincubated with EBV+ AGS cells tended to be immunosuppressed, which could be reversed by CD47 deficiency or blocking CD47. EBV resulted in cGAS-STING pathway activation, which stimulated CD47 expression and inhibited macrophage phagocytosis. Anti-CD47 therapy activated cGAS-STING signaling, which was responsible for production of IFN-ß, resulting in activation of antitumour immunity. Our results provide a promising new strategy for CD47-targeted immunotherapy in EBVaGC.

Surface-Enhanced Raman Scattering Enantioselective Detection of Gastric Cancer-Related d-Amino Acids in Saliva Based on Enzyme-Mediated Cascade Reaction.

The unusual d-amino acids (d-AAs), as the counter enantiomer of usual l-amino acids (l-AAs), have evoked increasing attention because of their potential relevance with diseases. Accordingly, it is essential to establish sensitive and selective detection methods for d-AAs without the interferences from l-AAs. The surface-enhanced Raman scattering (SERS) technique is efficacious for the detection of molecules but routinely ineffective in enantiomeric differentiation. d-Proline (d-Pro) and d-alanine (d-Ala) are regarded as biomarkers of gastric cancer. Herein, Raman-active boronate modified SERS chips are constructed to develop a d-amino acid oxidase (DAAO)-mediated cascade reaction-based SERS enantioselective assay for d-Pro and d-Ala. The principle is that DAAO selectively catalyzes the deamination of d-Pro and d-Ala, and the produced H2O2 oxidizes boronate to present a new SERS peak at 883 cm-1 for quantitative analysis in a ratiometric way. A linear range from 20 to 400 µmol/L and a limit of detection down to 14.8 µmol/L are reached. In addition, interferences from l-AAs and many other possible species coexisting in biofluids with the detection of d-Pro and d-Ala are ignorable. Enzyme-mediated cascade reaction-based SERS chips are further utilized for saliva sample analysis, and the total levels of d-Pro and d-Ala in salivary samples from gastric cancer patients are much higher than those of healthy persons. This work provides a solution for SERS enantioselective analysis and noninvasive screening chiral biomolecules for disease diagnosis.

Circ_0071589 contributes to growth, angiogenesis, and metastasis of colorectal cancer through regulating miR-296-5p/EN2 axis.

To explore the function and regulation mechanism of circ_0071589 in colorectal cancer (CRC). The expression levels of circ_0071589, microRNA-296-5p (miR-296-5p), and Engrailed-2 (EN2) were detected by quantitative real-time polymerase chain reaction (qRT-PCR). Western blot was performed to check the protein levels of EN2 and apoptosis-related proteins. Cell colony formation and 5-Ethynyl-29-deoxyuridine (EdU) assay were used to exhibit cell proliferation. Cell apoptosis was shown by flow cytometry. Tube formation assay manifested the angiogenesis ability of CRC cells. Transwell assay demonstrated cell migration and invasion. The interaction between miR-296-5p and circ_0071589 or EN2 was identified by dual-luciferase reporter assay. The effect of circ_0071589 on tumor formation was demonstrated by in vivo tumor formation experiments. Immunohistochemical (IHC) assay was used to detect the positive cell rate of Ki67 in tumor tissue. Circ_0071589 was upregulated in CRC tissue and cells. Circ_0071589 knockdown repressed CRC cells proliferation, angiogenesis, migration, invasion, and promoted cell apoptosis. MiR-296-5p was downregulated in CRC tissue and cells. And miR-296-5p inhibitor could reverse the malignant phenotypes and angiogenesis inhibition of CRC cells caused by circ_0071589 knockdown. Additionally, miR-296-5p decreased CRC cell colony formation, EdU-positive cells, angiogenesis, and increased cell apoptosis through reducing the expression level of EN2. Finally, circ_0071589 silencing inhibited tumor formation in vivo. Circ_0071589 upregulated EN2 expression through sponging miR-296-5p, thereby promoting the malignant phenotype and angiogenesis of CRC cells, which provided a new target for the treatment of CRC.

Fully Two-Dimensional Incommensurate Charge Modulation on the Pd-Terminated Polar Surface of PdCoO2.

Here, we use low-temperature scanning tunneling microscopy and spectroscopy to study the polar surfaces of PdCoO2. On the CoO2-terminated polar surface, we detect the quasiparticle interference pattern originating from the Rashba-like spin-split surface states. On the well-ordered Pd-terminated polar surface, we observe a regular lattice that has a larger lattice constant than the atomic lattice of PdCoO2. In comparison with the shape of the hexagonal Fermi surface on the Pd-terminated surface, we identify this regular lattice as a fully two-dimensional incommensurate charge modulation that is driven by the Fermi surface nesting. More interestingly, we also find the moiré pattern induced by the interference between the two-dimensional incommensurate charge modulation in the Pd layer and its atomic lattice. Our results not only show a new charge modulation on the Pd surface of PdCoO2 but also pave the way for fully understanding the novel electronic properties of this material.

Zhizhu decoction alleviates slow transit constipation by regulating aryl hydrocarbon receptor through gut microbiota.

CONTEXT: Slow transit constipation (STC), the most common type of constipation, seriously affects the life of patients. Zhizhu decoction (ZZD), a traditional Chinese medicine compound, has is effective against functional constipation, but the mechanism is still unclear. OBJECTIVE: This research explores the mechanism of ZZD on STC from the perspective of metabolomics and gut microbiota. MATERIALS AND METHODS: Fifty-four C57BL/6 mice were randomly divided into six groups (n = 9): control (control); STC (model); positive control (positive); low-dose (5 g/kg; L-ZZD), medium-dose (10 g/kg; M-ZZD), and high-dose (20 g/kg; H-ZZD) ZZD treatment. Following treatment of mice with ZZD for two weeks, the changes in intestinal motility, colon histology, intestinal neurotransmitters, and aryl hydrocarbon receptor (AHR) pathway determined the effects of ZZD on the pathophysiology of STC. LC-MS targeting serum metabolomics was used to analyze the regulation of ZZD on neurotransmitters, and 16S rRNA high-throughput sequencing was used to detect the regulation of the gut microbiome. RESULTS: ZZD had the highest content of naringin (6348.1 mg/L), and could significantly increase the 24 h defecations (1.10- to 1.42-fold), fecal moisture (1.14-fold) and intestinal transport rate (1.28-fold) of STC mice, increased the thickness of the mucosal and muscular tissue (1.18- to 2.16-fold) and regulated the neurotransmitters in the colon of STC mice. Moreover, ZZD significantly activated the AHR signaling pathway, and also affected the composition of gut microbiota in STC mice. DISCUSSION AND CONCLUSIONS: The beneficial effect and the possible mechanism of ZZD on STC could provide a theoretical basis for the broader clinical application of ZZD.

Roles of the Narrow Electronic Band near the Fermi Level in 1T-TaS_{2}-Related Layered Materials.

Here we use low-temperature scanning tunneling microscopy and spectroscopy to reveal the roles of the narrow electronic band in two 1T-TaS_{2}-related materials (bulk 1T-TaS_{2} and 4H_{b}-TaS_{2}). 4H_{b}-TaS_{2} is a superconducting compound with alternating 1T-TaS_{2} and 1H-TaS_{2} layers, where the 1H-TaS_{2} layer has a weak charge density wave (CDW) pattern and reduces the CDW coupling between the adjacent 1T-TaS_{2} layers. In the 1T-TaS_{2} layer of 4H_{b}-TaS_{2}, we observe a narrow electronic band located near the Fermi level, and its spatial distribution is consistent with the tight-binding calculations for two-dimensional 1T-TaS_{2} layers. The weak electronic hybridization between the 1T-TaS_{2} and 1H-TaS_{2} layers in 4H_{b}-TaS_{2} shifts the narrow electronic band to be slightly above the Fermi level, which suppresses the electronic correlation-induced band splitting. In contrast, in bulk 1T-TaS_{2}, there is an interlayer CDW coupling-induced insulating gap. In comparison with the spatial distributions of the electronic states in bulk 1T-TaS_{2} and 4H_{b}-TaS_{2}, the insulating gap in bulk 1T-TaS_{2} results from the formation of a bonding band and an antibonding band due to the overlap of the narrow electronic bands in the dimerized 1T-TaS_{2} layers.

Two phylogenetically and compartmentally distinct CDP-diacylglycerol synthases cooperate for lipid biogenesis in Toxoplasma gondii.

Toxoplasma gondii is among the most prevalent protozoan parasites, which infects a wide range of organisms, including one-third of the human population. Its rapid intracellular replication within a vacuole requires efficient synthesis of glycerophospholipids. Cytidine diphosphate-diacylglycerol (CDP-DAG) serves as a major precursor for phospholipid synthesis. Given the peculiarities of lipid biogenesis, understanding the mechanism and physiological importance of CDP-DAG synthesis is particularly relevant in T. gondii Here, we report the occurrence of two phylogenetically divergent CDP-DAG synthase (CDS) enzymes in the parasite. The eukaryotic-type TgCDS1 and the prokaryotic-type TgCDS2 reside in the endoplasmic reticulum and apicoplast, respectively. Conditional knockdown of TgCDS1 severely attenuated the parasite growth and resulted in a nearly complete loss of virulence in a mouse model. Moreover, mice infected with the TgCDS1 mutant became fully resistant to challenge infection with a hyper-virulent strain of T. gondii The residual growth of the TgCDS1 mutant was abolished by consecutive deletion of TgCDS2. Lipidomic analyses of the two mutants revealed significant and specific declines in phosphatidylinositol and phosphatidylglycerol levels upon repression of TgCDS1 and after deletion of TgCDS2, respectively. Our data suggest a "division of labor" model of lipid biogenesis in T. gondii in which two discrete CDP-DAG pools produced in the endoplasmic reticulum and apicoplast are subsequently used for the synthesis of phosphatidylinositol in the Golgi bodies and phosphatidylglycerol in the mitochondria. The essential and divergent nature of CDP-DAG synthesis in the parasite apicoplast offers a potential drug target to inhibit the asexual reproduction of T. gondii.

Comparison of immunological characteristics between paired mismatch repair-proficient and -deficient colorectal cancer patients.

BACKGROUND: Currently, mismatch repair-deficient (dMMR) status is a promising candidate for targeted immune checkpoint inhibition therapy in colorectal cancer (CRC) patients, however, the potential immunological mechanism has not yet been well clarified and some other predictors need to be excavated as well. METHODS: We collected 330 CRC patients by the match of mismatch repair-proficient (167) and dMMR (163), explored the relationship between MMR status and some important immune molecules including MHC class I, CD3, CD4, CD8, CD56, programmed death-1 and programmed death ligand-1, and investigated the risk factors for dMMR status as well as low MHC class I expression. The Pearson Chi square test was used for analyzing the associations between clinicopathological and immune characteristics and MMR status, and two categories logistic regression model was used for univariate and multivariate analysis to predict the odds ratio of risk factors for dMMR status and low MHC class I expression. RESULTS: Multivariate logistic regression analysis showed that low MHC class I and CD4 expression and high CD8 expression were significant risk factors for dMMR status [odds ratio (OR) = 24.66, 2.94 and 2.97, respectively; all p < 0.05] and dMMR status was the only risk factor for low MHC class I expression (OR = 15.34; p < 0.001). CONCLUSIONS: High CD8 and low MHC class I expression suggests the contradiction and complexity of immune microenvironment in dMMR CRC patients. Some other immunocytes such as CD56+ cells might also participate in the process of immune checkpoint inhibition, whereas needs further investigations.

The systemic immune-inflammation index is an independent predictor of survival for metastatic colorectal cancer and its association with the lymphocytic response to the tumor.

BACKGROUND: Systemic inflammation and immune dysfunction has been proved to be significantly associated with cancer progression and metastasis in many cancer types, including colorectal cancer. We examined the prognostic significance of the systemic immune-inflammation index (SII) in patients with metastatic colorectal cancer (mCRC) and the relationship between the lymphocytic response to the tumor and this index. METHODS: This retrospective study evaluated 240 consecutive patients with newly diagnosed stage IV mCRC who underwent surgical resection. The SII values were calculated based on preoperative laboratory data regarding platelet, neutrophil, and lymphocyte counts. Tumor-infiltrating lymphocytes were evaluated using the surgical specimens. The overall survival and their 95% confidence interval (95% CI) were estimated by regression analyses and the Kaplan-Meier method. RESULTS: After a mean follow-up of 26.7 (1.1-92.4) months, 146 patients (60.8%) died. In the univariate analysis, a high SII was significantly associated with poor overall survival (P = 0.009). The multivariable analysis also confirmed that a high SII was independently associated with poor overall survival (hazard ratio: 1.462, 95% confidence interval 1.049-2.038, P = 0.025). The SII value was significantly correlated with the TILs value at the tumor's center (P = 0.04), but not at the invasive margin (P = 0.39). When we evaluated overall survival for groupings of the tumor-infiltrating lymphocytes and SII values, we identified three distinct prognostic groups. The group with low tumor-infiltrating lymphocyte values and high SII values had the worst prognosis. CONCLUSIONS: A high SII value independently predicts poor clinical outcomes among patients with mCRC. In addition, combining the lymphocytic response to the tumor and SII could further enhance prognostication for mCRC.

Prognostic value of total number of lymph nodes retrieved differs between left-sided colon cancer and right-sided colon cancer in stage III patients with colon cancer.

BACKGROUND: The consensus is that a minimum of 12 lymph nodes should be analyzed at colectomy for colon cancer. However, right colon cancer and left colon cancer have different characteristics, and this threshold value for total number of lymph nodes retrieved may not be universally applicable. METHODS: The data of 63,243 patients with colon cancer treated between 2004 and 2012 were retrieved from the National Cancer Institute's Surveillance, Epidemiology, and End Results database. Multivariate Cox regression analysis was used to determine the predictive value of total number of lymph nodes for survival after adjusting for lymph nodes ratio. The predictive value in left-sided colon cancer and right-sided colon cancer was compared. The optimal total number of lymph nodes cutoff value for prediction of overall survival was identified using the online tool Cutoff Finder. Survival of patients with high total number of lymph nodes (≥12) and low total number of lymph nodes (< 12) was compared by Kaplan-Meier analysis. RESULTS: After stratifying by lymph nodes ratio status, total number of lymph nodes≥12 remained an independent predictor of survival in the whole cohort and in right-sided colon cancer, but not in left-sided colon cancer. The optimal cutoff value for total number of lymph nodes was determined to be 11. Low total number of lymph nodes (< 11) was associated with significantly poorer survival after adjusting for lymph nodes ratio in all subgroups except in the subgroup with high lymph nodes ratio (0.5-1.0). CONCLUSIONS: Previous reports of the prognostic significance of total number of lymph nodes on node-positive colon cancer were confounded by lymph nodes ratio. The 12-node standard for total number of lymph nodes may not be equally applicable in right-sided colon cancer and left-sided colon cancer.

Second primary colorectal cancer after the initial primary colorectal cancer.

BACKGROUND: Initial primary colorectal cancer (IPCRC) has a high risk of developing into second primary colorectal cancer (SPCRC). Right-sided colon cancer (RCC) and left-sided colon cancer (LCC) have different characteristics and are considered to be two different entities. However, the different risks for SPCRC in categorized tumor sites and SPCRC subcategorized sites have not been fully elucidated to date. We aimed to compare incidence and survival of IPCRC and SPCRC and characterize the risk factors of SPCRC while also comparing the different SPCRC characteristics. METHODS: We used the National Cancer Institute's Surveillance, Epidemiology, and End Results (SEER) data to compute standardized incidence ratios (SIR) in order to estimate risk of SPCRC after IPCRC diagnosis. The most prominent risk factors for SPCRC were measured by multivariate regression analysis and the temporal trend of SPCRC incidence was assessed with Joinpoint regression. Survival of patients with SPCRC and IPCRC was compared by Kaplan-Meier analysis. RESULTS: Patients with IPCRC were 1.73 times more likely to develop SPCRC (SIR = 1.73, 95% CI 1.69-1.78). SPCRC incidence declined since the first 8 years of IPCRC diagnosis to baseline. We demonstrated poorer survival with SPCRC compared with IPCRC while second RCC resulted in better survival compared with second LCC. Black ethnicity, age range 70-79, and LCC were associated with the highest risk of developing SPCRC. CONCLUSION: The characteristic differences between second LCC and RCC were relatively narrow. Furthermore, in those with SPCRC, RCC had the best survival outcome.

The microRNA-423-3p-Bim Axis Promotes Cancer Progression and Activates Oncogenic Autophagy in Gastric Cancer.

Human serum microRNAs (miRNAs) have been shown to serve as disease fingerprints for predicting survival of cancer patients. However, the roles of specific miRNAs involved in gastric cancer (GC) are largely unknown. In this study, miRNA profiling was performed on sera obtained from six patients in good- and poor-survival groups. Expression of miR-423-3p was validated by quantitative RT-PCR in another 67 GC serum samples and paired normal and cancerous gastric tissues. Luciferase reporter assays were used to identify the target gene Bcl-2-interacting mediator of cell death (Bim). As a result, between the good-survival and poor-survival groups, the expression of nine serum miRNAs was altered more than two-fold. Among these, miR-423-3p was significantly increased in the poor-survival group, and its overexpression in GC tissues predicted poor survival in 119 patients with GC. miR-423-3p was found to promote cell proliferation, migration, and invasion in cell lines and animal models. Mechanistically, knockdown of the autophagy-related gene (Atg) 7 rescued the GC-promoting effect of miR-423-3p. In conclusion, miR-423-3p activates oncogenic and Beclin-1-dependent autophagy and promotes GC progression by reducing the expression of Bim. The newly identified miR-423-3p-Bim axis might be a potential therapeutic target in GC.

Clinical baseline and prognostic difference of platelet lymphocyte ratio (PLR) in right-sided and let-sided colon cancers.

BACKGROUND: Right-sided colon cancer (RCC) and left-sided colon cancer (LCC) differ with respect to their biology and genomic patterns, but inflammatory index variation did not fully investigate. This study aimed to examine the difference of inflammatory indexes and its value between RCC and LCC. METHODS: The differences of common clinicopathologic factors, inflammatory indexes including PLR (Platelet lymphocyte ratio) between LCC and RCC were analyzed in the training cohort with logistic regression model, subsequently, confirmed in validation cohort. Kaplan-Meier analysis was applied for the analysis of the survival difference distinguished by the PLR and the Nonparametric Test was adopted to demonstrate the difference of PLR variation with the standard TNM classification between RCC and LCC. RESULTS: A total of 1846 CRC patients entered the study, 744 (40.3%) patients were RCC, 1102 (59.7%) were LCC. The patients' number in both cohorts was 923. It was found that LCC patients in the training cohort significantly to be with higher CEA, adenocarcinoma, early UICC/AJCC stage, p-MMR (mismatch-repair proficient), and lower PLR, and the later four features were confirm in validation cohort. Higher PLR, the unique inflammatory index, was significantly associated with poorer OS in LCC cohort (P = 0.002) and was elevated with the TNM stage in the LCC patients (P < 0.001), however, the two relationships did not sustain in RCC patients. CONCLUSION: Expect the classical characteristics, PLR, an inexpensive and easily assessable inflammatory index was found first time to be significant differ between LCC and RCC. Further, elevated PLR associated with poor OS (overall survival) in the LCC and more common in advanced TNM stage.

Prognostic significance of Epstein-Barr virus infection in gastric cancer: a meta-analysis.

BACKGROUND: The prognostic significance of Epstein-Barr virus (EBV) infection in gastric cancer (GC) remains unclear. Recently, a number of studies have investigated the association between EBV infection and the prognosis of GC with controversial results. We therefore conducted a meta-analysis to assess its prognostic significance. METHODS: PubMed and EMBASE were searched for studies up to October 1, 2014. We investigated the association between EBV infection with survival in patients with GC. The pooled hazard ratio (HR) and its 95% confidence interval (CI) were calculated to evaluate risk. RESULTS: A final analysis of 8,336 patients with GC from 24 studies was performed. Our analysis results indicated that the pooled HR was 0.67 (95% CI: 0.55-0.79; Z = 11.18, P < 0.001). Subgroup analyses stratified by region revealed that the protective role of EBV infection only remained in the Asian population (HR: 0.62, 95% CI: 0.48-0.75; P < 0.001). When stratified by study quality and statistical methodology, the protective role could also be identified in high quality studies (HR: 0.67, 95% CI: 0.55-0.79) and in univariate analysis studies (HR: 0.62, 95% CI: 0.50-0.74). There was no evidence of significant heterogeneity and publication bias. CONCLUSIONS: The presence of EBV has a favorable impact on GC patient's survival, especially in an Asian population. Future updated studies, especially large-scale randomized controlled studies stratified by region, are warranted as validation studies.

Astragaloside IV regulates circ_0001615 and miR-873-5p/LASP1 axis to suppress colorectal cancer cell progression.

Astragaloside IV (AS-IV) has exhibited pivotal anti-cancer efficacy in multiple types of cancer, including colorectal cancer (CRC). Meanwhile, circular RNA (circRNA) circ_0001615 has been reported to be involved in the malignant development of CRC. Herein, this study is expected to figure out the interaction between circ_0001615 and AS-IV on CRC progression. The 50% inhibition concentration (IC50), proliferation, apoptosis, and migration were detected by Cell Counting Kit-8 (CCK-8), 5-ethynyl-2'-deoxyuridine (EdU), flow cytometry, and wound healing assays. The expression of related proteins was examined by western blot. Circ_0001615, microRNA-873-5p (miR-873-5p), and LIM and SH3 protein 1 (LASP1) levels were detected by real-time quantitative polymerase chain reaction (RT-qPCR). The binding between miR-873-5p and circ_0001615, or LASP1, was predicted by Starbase, followed by verification by dual-luciferase reporter and RNA immunoprecipitation (RIP) assays. The biological role of circ_0001615 and AS-IV on CRC tumor growth was detected by the xenograft tumor model in vivo. According to the IC50 of AS-IV in CRC cells, the 100 ng/mL AS-IV treatment for 24 h was chosen for the following research: Our data confirmed that AS-IV is a beneficial anti-cancer agent in CRC cells. Furthermore, circ_0001615 and LASP1 expression were increased, and miR-873-5p was decreased in CRC patients and cell lines, whereas their expression exhibited an opposite trend in AS-IV-treated cells. Functionally, applying AS-IV might act as a beneficial anti-cancer effect by downregulating circ_0001615 in CRC cells in vitro. Mechanically, circ_0001615 serves as a sponge for miR-873-5p to affect LASP1 expression. In addition, AS-IV inhibited CRC cell growth in vivo by modulating circ_0001615. Overall, AS-IV could mitigate CRC development, at least in part, through the circ_0001615/miR-873-5p/LASP1 axis. These findings support a theoretical basis for an in-depth study of the function of AS-IV and the clinical treatment of CRC.

Endosonography Elastography and Magnetic Resonance Imaging in the Restaging and Response Assessment of Rectal Cancer After Neoadjuvant Therapy.

ABSTRACT: The objective of this academic research is to assess the efficacy of conventional endorectal ultrasound (ERUS), ultrasonic shear wave elastography (SWE), and magnetic resonance imaging (MRI) techniques in evaluating the impact of neoadjuvant therapy (nCRT). Forty-five patients with advanced low rectal cancer (T ≥ 3) were included. Before and after nCRT, ERUS, SWE, and MRI evaluations were conducted. The T staging of ultrasound (uT) and MRI (mT) were evaluated and compared with the pathological T staging (ypT). The accuracy of the 2 diagnostic methods for T staging, and T downstaging was evaluated. The ultrasound elasticity difference and relative elasticity before and after treatment and pathological T downstaging were compared, and its cutoff value and the area under the curve were assessed. In terms of T staging accuracy after chemoradiotherapy, the values for ERUS, ERUS combined with SWE, and MRI were 64.4%, 71.1%, and 62.2%, respectively. No significant difference was observed among these groups ( P > 0.05). The accuracy of uT downstaging was 84.4%, and that of mT downstaging was 88.9%. The receiver operating characteristic curve of uLD and elastic differences and relative elasticity of T downstaging after treatment were 0.754, 0.817, and 0.886, respectively (all P < 0.05). Both ERUS and MRI can evaluate ypT downstaging. The indicators for evaluating T downstaging are uLD, elasticity difference, and relative elasticity, providing more reference for clinical assessment of nCRT efficacy.

STAT3-mediated up-regulation of DAB2 via SRC-YAP1 signaling axis promotes Helicobacter pylori-driven gastric tumorigenesis.

BACKGROUND: Helicobacter pylori (H pylori) infection is the primary cause of gastric cancer (GC). The role of Disabled-2 (DAB2) in GC remains largely unclear. This study aimed to investigate the role of DAB2 in H pylori-mediated gastric tumorigenesis. METHODS: We screened various datasets of GC to analyze DAB2 expression and cell signaling pathways. DAB2 expression was assessed in human GC tissue microarrays. H pylori infection in vivo and in vitro models were further explored. Immunostaining, immunofluorescence, chromatin immunoprecipitation, co-immunoprecipitation, Western blot, quantitative polymerase chain reaction, and luciferase reporter assays were performed in the current study. RESULTS: The bioinformatic analysis verified that DAB2 was 1 of the 8 genes contributed to tumorigenesis and associated with poor prognosis in GC. The median overall survival and disease-free survival rates in DAB2high group were significantly less than those in DAB2low group. These findings demonstrated that H pylori transcriptionally activated DAB2 expression via signal transducer and activator of transcription 3 (STAT3)-dependent pathway. By bioinformatics analysis and knockdown or overexpression of DAB2, we found that DAB2 upregulated Yes-associated protein 1 (YAP1) transcriptional activity. Mechanistically, DAB2 served as a scaffold protein for integrin beta 3 (ITGB3) and SRC proto-oncogene non-receptor tyrosine kinase (SRC), facilitated the phosphorylation of SRC, promoted the small GTPase ras homolog family member A (RHOA) activation and phosphorylation of YAP1, and ultimately enhanced the YAP1 transcriptional activity. CONCLUSIONS: Altogether, these findings indicated that DAB2 is a key mediator in STAT3-regulated translation of YAP1 and plays crucial roles in H pylori-mediated GC development. DAB2 might serve as a novel therapeutic target for GC.