Strategies in product engineering of mesenchymal stem cell-derived exosomes: unveiling the mechanisms underpinning the promotive effects of mesenchymal stem cell-derived exosomes.

Articular cartilage injuries present a significant global challenge, particularly in the aging population. These injuries not only restrict movement due to primary damage but also exacerbate elderly degenerative lesions, leading to secondary cartilage injury and osteoarthritis. Addressing osteoarthritis and cartilage damage involves overcoming several technical challenges in biological treatment. The use of induced mesenchymal stem cells (iMSCs) with functional gene modifications emerges as a solution, providing a more stable and controllable source of Mesenchymal Stem Cells (MSCs) with reduced heterogeneity. Furthermore, In addition, this review encompasses strategies aimed at enhancing exosome efficacy, comprising the cultivation of MSCs in three-dimensional matrices, augmentation of functional constituents within MSC-derived exosomes, and modification of their surface characteristics. Finally, we delve into the mechanisms through which MSC-exosomes, sourced from diverse tissues, thwart osteoarthritis (OA) progression and facilitate cartilage repair. This review lays a foundational framework for engineering iMSC-exosomes treatment of patients suffering from osteoarthritis and articular cartilage injuries, highlighting cutting-edge research and potential therapeutic pathways.

Celestial Insights: Unraveling the Role of miR-3682-3p in Hepatocellular Carcinoma.

ABSTRACT: Hepatocellular carcinoma (HCC) remains a formidable oncological challenge, calling for innovative therapeutic strategies to improve patient outcomes. MicroRNAs have emerged as key regulators in cancer, and miR-3682-3p shows potential as a diagnostic and prognostic biomarker in HCC. We conducted a comprehensive study to uncover its role in HCC biology, revealing dysregulation and clinical associations. Target gene analysis provided insights into potential molecular mechanisms. Moreover, we explored its impact on the tumor microenvironment, immune cell infiltration, and therapy responses. Our findings highlight miR-3682-3p as a promising candidate for further investigations and potential therapeutic strategies in HCC management.

Slowed Intestinal Transit Induced by Less Mucus in Intestinal Goblet Cell Piezo1-Deficient Mice through Impaired Epithelial Homeostasis.

Mucus secreted by goblet cells (GCs) may play an important role in intestinal transit function. Our previous study found that Piezo1 protein is essential for GC function; however, the effect of GC Piezo1 on intestinal transit function is unclear. Our study aimed to investigate the effect of Piezo1 in GCs on intestinal transit and the potential mechanism. We compared intestinal mucus, fecal form, intestinal transit time, intestinal epithelial cell composition, and stem cell function in WT and GC-specific Piezo1-deficient (Piezo1ΔGC) mice. Our results revealed a correlation between mucus and intestinal transit: the less mucus there was, the slower the intestinal transit. Piezo1 deficiency in GCs led to decreased mucus synthesis and also disrupted the ecological niche of colon stem cells (CSCs). Through organoid culture, we found that the capacity of proliferation and differentiation in Piezo1ΔGC mouse CSCs was significantly decreased, which also led to a reduced source of GCs. Further studies found that the reduced Wnt and Notch signals in colon crypts might be the potential mechanism. These results indicated the importance of GC Piezo1 in intestinal transit function, which acts by maintaining the homeostasis of intestinal epithelial cells and mucus.

Construction and Verification of a Fibroblast-Related Prognostic Signature Model for Colon Cancer.

Traditionally, cancer-associated fibroblasts (CAFs), an essential component of tumor microenvironment, were exert a crucial part in colon cancer progression. In this study, single-cell RNA-sequencing (scRNA-seq) data from 23 and bulk RNA-seq data from 452 colon cancer patients were extracted from the GEO database and TCGA-COAD and GEO databases, respectively. From single-cell analysis, 825 differentially expressed genes (DEGs) in CAFs were identified between each pair of six newly defined CAFs, named enCAF, adCAF, vaCAF, meCAF, erCAF, and cyCAF. Cell communication analysis with the iTALK package showed communication relationship between CAFs, including cell autocrine, cytokine, and growth factor subtypes, such as receptor-ligand pairs of TNFSF14-LTBR, IL6-F3, and IL6-IL6ST. Herein, we demonstrated the presence and prognostic value of adCAF and erCAF in colon cancer based on CIBERSORTx, combining single-cell marker genes and transcriptomics data. The prognostic significance of the enCAF and erCAF has been indirectly proved by both the correlation analysis with macrophages and CAFs, and the quantitative reverse transcription-polymerase chain reaction (qRT-PCR) experiment based on 20 paired tumor samples. A prognostic model was constructed with 10 DEGs using the LASSO Cox regression method. The model was validated using two testing datasets, indicate a significant survival accuracy (p < 0.0025). Correlation analyses between clinical information, such as age, gender, tumor stage and tumor features (tumor purity and immune score), and risk scores revealed our CAF-related model's robustness and excellent performance. Cell infiltration analysis by xCell revealed that the interaction between CAFs and multiple non-specific immune cells such as macrophages and the dendritic cell was a vital factor affecting immune score and prognosis. Finally, we analyzed how common anti-cancer drugs, including camptothecin, docetaxel and bortezomib, and immunotherapy, such as anti-PD-1 treatment, could be different in low-risk and high-risk patients inferred from our CAF-related model. In conclusion, the study utilized refined colon cancer fibroblast subsets and established the prognostic effects from the interaction with nonspecific immune cell.

Massive gastrointestinal bleeding after endoscopic rubber band ligation of internal hemorrhoids: A case report.

BACKGROUND: Rubber band ligation (RBL) using rigid anoscope is a commonly recommended therapy for grade I-III symptomatic internal hemorrhoids. Severe complications of RBL include pain, hemorrhage and sepsis. Flexible endoscopic RBL (ERBL) is now more commonly used in RBL therapy but few severe complications have been reported. Here we report on a case of massive bleeding after ERBL. CASE SUMMARY: A 31-year-old female was admitted to the department of gastroenterology with a chief complaint of discontinuous hematochezia for 2 years. No previous history, accompanying diseases or drug use was reported. Physical examination and colonoscopy showed grade II internal hemorrhoids. The patient received ERBL therapy. Five days after ligation, the patient presented with mild hematochezia. On days 7 and 9 after ligation, she presented with a large amount of rectal bleeding, dizziness and weakness. Emergency colonoscopy revealed active bleeding and an ulcer in the anal wound. The patient received two sessions of hemoclipping on days 7 and 9 to treat the bleeding. No further bleeding was reported up to day 15 and she was discharged home. Although the hemorrhoid prolapse disappeared after ERBL, she was dissatisfied with the subsequent complications. CONCLUSION: ERBL therapy is an effective treatment for symptomatic internal hemorrhoids with satisfactory short and long-term recovery. Pain and anal bleeding are the most frequently reported postoperative complications. Coagulation disorders complicate the increased risk of bleeding. Although rarely reported, our case reminds us that those patients without coagulation disorders are also at risk of massive life-threatening bleeding and need strict follow-up after ligation.

The m6A RNA Modification Quantity and the Prognostic Effect of Reader YTHDC2 in Colorectal Cancer.

Background: N6-methyladenosine (m6A) modification plays crucial roles in cancers. However, its alteration in colorectal cancer (CRC) is still poorly described. The purpose of this study is to explore the change of m6A modification and the function of m6A binding protein YTHDC2 in CRC. Methods: The global level of m6A modification was detected by mass spectrometry and dot blotting assay. The expression of YTHDC2 was investigated using The Cancer Genome Atlas and using real-time polymerase chain reaction (RT-qPCR), western blotting, and immunohistochemistry based on CRC tissues. Kaplan-Meier analysis and Cox proportional hazards regression were performed to analyze the prognostic value of YTHDC2. RNA immunoprecipitation (RIP)-seq and m6A immunoprecipitation (MeRIP)-seq were used to explore the direct targets of YTHDC2. Gene oncology (GO) and Gene Set Enrichment Analysis (GSEA) were used to explore the pathways that could be influenced by YTHDC2. Results: No significant difference was observed in the global level of m6A modification on total RNA or mRNA between CRC and adjacent nontumor tissues. We further found a significant decreasing of YTHDC2 in CRC tissues. Kaplan-Meier analysis indicated that lower expression of YTHDC2 was related to the worse disease-free survival and overall survival. In addition, lower expression of YTHDC2 was an independent worse prognostic factor in univariate and multivariate Cox regression analysis. Using YTHDC2-RIP-seq and MeRIP-seq, we identified that YTHDC2 could participate in several important biological signal pathways. Conclusions: In summary, this study suggested that the global level of m6A did not change in CRC and identified that lower YTHDC2 as a prognostic marker for worse survival of CRC.

Regorafenib in Refractory Metastatic Colorectal Cancer: A Multi-Center Retrospective Study.

Background: Regorafenib improves progression-free survival (PFS) and overall survival (OS) in patients with refractory metastatic colorectal cancer (mCRC). Here, we report the treatment patterns of regorafenib in the third- or late-line setting for mCRC in four centers in China. Patients and Methods: Patients with refractory mCRC in four centers in China administered regorafenib from February 1, 2018 to June 31, 2021 were enrolled. Patients were grouped into 3 cohorts, namely, the monotherapy (regorafenib alone), chemo (regorafenib plus chemotherapy), and immune [regorafenib plus anti-PD1 (programmed cell death 1) antibodies] groups. Demographic, clinical, survival and safety data were retrospectively analyzed. Results: A total of 177 patients were included in this study. Of them, 116 (65.5%) were treated with regorafenib alone, while 28 (15.9%) and 33 (18.6%) were administered regorafenib plus chemotherapy and anti-PD1 antibodies, respectively. The median followed-up time was 9.2 months. The disease control rate (DCR) was 40.7%. The median PFS (mPFS) was 2.43 months and the median OS (mOS) was 12.2 months. The immune group had longer median PFS (3.5 m vs. 2.2 m, p = 0.043) compared with the monotherapy group. Patients administered regorafenib plus chemotherapy had longer median OS (15.9 m vs. 8.4 m, p = 0.032) compared with the monotherapy group. Patients who began regorafenib treatment at 120 mg had longer median PFS and OS compared with those who began at 80 mg (PFS: 3.7 m vs. 2.0 m; p <0.001; OS: 13.4 m vs. 10.2 m; p = 0.005). Patients with a final dose of 120 mg had longer median PFS and OS compared with the 80 mg or less group (PFS: 5.0 m vs. 2.3 m; p = 0.045; OS: UR (unreach) vs. 10.9 m; p = 0.003). There were 87.0% (154/177) patients who experienced AEs. Three groups had similar rates of AEs (86.2% vs. 89.3% vs. 87.9%; p = 0.89). Conclusion: Patients administered regorafenib alone or regorafenib in combination with other agents were relieved to some extent, with a disease control rate of 40.7%. Regorafenib plus anti-PD1 antibodies showed better PFS, while regorafenib plus chemotherapy had the most benefit in OS. There was no significant difference among three groups in terms of AEs.

The Establishment and Experimental Verification of an lncRNA-Derived CD8+ T Cell Infiltration ceRNA Network in Colorectal Cancer.

Background: Long noncoding RNAs (LncRNA) lead a vital role in colorectal cancer (CRC) development. The infiltrating CD8+ T cell is the main target of immunotherapy. Our study aimed to figure out the potential mechanism of lncRNAs regulating the function of CD8+ T cells in CRC. Methods: We collected bulk RNA-seq, miRNA-seq, and single-cell RNA-seq (scRNA-seq) data from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) database. The cibersort algorithm and correlation analysis were used to estimate the abundance of CD8+ T cells and screened out the most relevant lncRNAs. We used scRNA-seq data to identify the main cell lncRNA expressed. Furthermore, one competing endogenous RNA (ceRNA) network focusing on the potential mechanism of lncRNA-derived CD8+ T cell infiltration was constructed. We established a co-culture system to assess the immunosuppressive function of the lncRNA. And we evaluated the effects of the lncRNA on CD8+ T cell cytotoxicity by flow cytometry, qPCR, and clone formation assay. Results: Three CD8+ T cell infiltration-related lncRNAs were identified, and LINC00657 was expressed mainly in tumor cells, negatively associated with CD8+ T cell infiltration. Hsa-miRNA-1224-3p and hsa-miRNA-338-5p and SCD, ETS2, UBE2H, and YY1 were identified to construct the ceRNA network. Immunosuppression-related tumor marker CD155 was proved to be positively correlated with LINC00657 and mRNAs in the ceRNA network. In addition, we proved that LINC00657 could impair the cytotoxicity of CD8+ T cells, and its expression was positively associated with CD155 in vitro. Conclusions: We successfully constructed an lncRNA-derived CD8+ T cell infiltration ceRNA network in CRC. LINC00657 may play a leading role in the CRC immune escape and could be a novel immunotherapy target.

No.253 Lymph Nodes Metastasis in Left-Sided Colorectal Cancer Liver Metastasis (CRLM) Patients: Incidence and Prognosis.

Background: No.253 lymph node is the gateway to systemic metastasis for left-sided colorectal cancer. However, the value of D3 resection is still controversial. This study aimed to identify the incidence rate and prognostic value of 253LN metastasis in patients with left-sided colorectal cancer liver metastasis (CRLM) mainly through blood vessels and thus to provide theoretical basis for 253LN resection. Methods: From February 2012 to February 2019, a total of 281 patients who underwent curative resection for both primary and metastatic tumors were collected retrospectively. The clinicopathological and genetic characteristics were compared between 58 patients with positive 253LN and 223 patients with negative. Relapse-free survival (RFS) and overall survival (OS) were compared with Kaplan-Meier method. Cox regression analysis and a forest plot were conducted for RFS. Results: The incidence of 253LN metastasis in left-sided CRLM was 20.64% (58/281). Those with 253LN positive were T4 stage, N2 stage, and D1/D2 lymph nodes metastatic. About 10.3% (8/78) 253LN positive patients were D1/D2 negative. The 253LN metastasis was an independent risk factor for relapse after curative surgery, but not for OS. Patients with 253LN metastasis had worse RFS, especially in female, adenocarcinoma, poorly differentiated, pT3, preoperative serum CA199 < 37 U/mL, bilobar liver metastasis, without preoperative chemotherapy, KRAS, NRAS, or BRAF wild type. Conclusion: The incidence of 253LN metastasis in left-sided CRLM is 20.64%, and skip metastasis rate is 10.3%. The 253LN status is an independent prognostic risk factor for RFS but not for OS after curative surgery. Routine resection of 253LN should be applied in curative surgery of left-sided CRLM.

Integrated Analysis of Expression and Prognostic Values of Acyl-CoA Dehydrogenase short-chain in Colorectal Cancer.

Background: Acyl-CoA dehydrogenase short-chain (ACADS) is a crucial enzyme in the fatty acid metabolism pathway located in mitochondria. However, the expression level and prognostic value of ACADS in colorectal cancer (CRC) remain unclear. Methods: The mRNA and protein expression data of ACADS was obtained from The Cancer Genome Atlas (TCGA), Clinical Proteomic Tumor Analysis Consortium (CPTAC), and Oncomine. Prognostic values of ACADS were calculated using Kaplan-Meier survival analysis. Correlations between ACADS and immune infiltration were estimated using TIMER, CIBERSORT, EPIC, quanTIseq, and xCell. The UALCAN and MEXPRESS databases were utilized for Methylation analysis. The co-expression analysis based on mRNA expression and interaction network of ACADS were performed via several online tools. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis on ACADS co-expressed genes were performed using the Metascape. Results: The expression analysis demonstrated that ACADS was down-regulated in CRC tissues compared with paired normal tissue. Expression of ACADS was found to be significantly associated with clinical cancer stages and the consensus molecular subgroups (CMS) constituent ratio in CRC patients. Besides, lower ACADS expression was found to predict poor prognosis and be significantly associated with common immune checkpoint genes and MMR genes in CRC. ACADS expression levels were positively related to B cells, CD4+ T cells, CD8+ T cells, M1 macrophages, neutrophils, and Tregs, while negatively correlated with M0 macrophages, M2 macrophages. The methylation level of ACADS in normal tissues was significantly higher than that in tumor tissues, and several methylation sites were identified. The enrichment analysis suggested the co-expressed genes mainly enriched in cell mitochondrial metabolism. Conclusions: The present study provided multilevel evidences for expression of ACADS in CRC and the function of ACADS in prognostic prediction, immune infiltration, and methylation. ACADS might have the potential as the novel biomarker and therapeutic target in CRC patients.

Impact of Inadequate Number of Lymph Nodes Examined on Survival in Stage II Colon Cancer.

BACKGROUND: Inadequate number of lymph nodes examined was not uncommon. We aimed to assess the clinical role of inadequate number of lymph nodes examined in stage II colon cancer. METHODS: The cancer data used in our study were obtained from the SEER (Surveillance, Epidemiology and End Results) program. Using the chi-square test, all the variables obtained in our study were compared based on whether patients had enough (≥12) lymph nodes examined. Kaplan-Meier analysis was used for overall survival (OS) analysis, and log-rank test was applied to compare different N stages with the total number of lymph nodes examined. Multivariate analysis was carried out by creating a Cox proportional hazard model to assess the prognostic roles of different variables. RESULTS: In total, 80,296 stage II/III colon cancer patients were recruited for our study. N0 stage with <8 lymph nodes examined would present with a worse prognosis compared to N1 stage (5-year OS rates, 51.6% vs. 57.1%, p < 0.001). Multivariate analyses indicated that OS of N0 stage with <8 lymph nodes examined was similar to that of N1 stage after adjusting for other recognized prognostic factors [hazard ratios (HRs) = 1.051, 95% confidence intervals (CIs) = 1.014-1.090, p = 0.018]. CONCLUSIONS: N0 stage with less than eight lymph nodes examined in stage II colon cancer presented with no better OS compared to that of N1 stage. Stage II colon cancer with less than eight lymph nodes examined needed to be given greater emphasis in clinical practice.

Exogenous l-fucose protects the intestinal mucosal barrier depending on upregulation of FUT2-mediated fucosylation of intestinal epithelial cells.

FUT2, a protein that uses l-fucose to mediate fucosylation of intestinal epithelial cells, is one of the detected gene variants in IBD patients. We aimed to investigate whether exogenous l-fucose could be an enteral nutritional supplement to protect intestinal barrier function. The effect of l-fucose on the restoration of epithelial barrier function in both the DSS-induced colitis mouse model and LPS-stimulated Caco-2 cells was investigated, and the impact on fucosylation of epithelial cells was examined. The severity of DSS-induced colitis was significantly reduced by l-fucose. Restoration of epithelial barrier function by l-fucose was detected. Direct l-fucose-mediated protection of tight junctions was observed in Caco-2 cells. Moreover, exogenous l-fucose promoted the exogenous metabolic pathway of l-fucose, and fucosylation of epithelial cells both in vivo and in vitro. Moreover, knockout of the FUT2 gene restrained fucosylation and the protective effect of l-fucose on barrier function. The severity of colitis was not improved by l-fucose in Fut2 knockout mice. Therefore we conclude that exogenous l-fucose protects intestinal barrier function and relieves intestinal inflammation via upregulation of FUT2-mediated fucosylation of intestinal epithelial cells.

Piezo1 regulates intestinal epithelial function by affecting the tight junction protein claudin-1 via the ROCK pathway.

AIMS: Defective tight junctions (TJs) can induce intestinal epithelial dysfunction, which participates in various diseases such as irritable bowel syndrome. However, the mechanisms of TJ defects remain unclear. Our study revealed the role of Piezo1 in regulating intestinal epithelial function and TJs. MATERIALS AND METHODS: The human colonic adenocarcinoma cell line Caco-2 were cultured on Transwell plate to form an epithelial barrier in vitro, and Piezo1 expression was manipulated using a lentivirus vector. Epithelial function was evaluated by measuring transepithelial electronic resistance (TEER) and 4-kDa FITC-dextran (FD4) transmission. TJ proteins (claudin-1, occludin, ZO-1) were evaluated by RT-PCR, western blot, and immunostaining analysis. Potential signal pathways, including the ROCK and Erk pathways, were detected. Moreover, to explore the regulatory effect of Piezo1 activity on epithelial function, inhibitors (ruthenium red, GsMTx4) and an agonist (Yoda1) were introduced both ex vivo and in vitro. KEY FINDINGS: Alteration of Piezo1 expression altered epithelial function and the expression of the tight junction protein claudin-1. Piezo1 expression regulated phosphorylated ROCK1/2 expression, whereas interference on ROCK1/2 prevented the regulation of claudin-1 by Piezo1. In both Caco-2 monolayer and mouse colon epithelium, Piezo1 activity directly modulated epithelial function and permeability. SIGNIFICANCE: Piezo1 negatively regulates epithelial barrier function by affecting the expression of claudin-1. Such regulation may be achieved partially via the ROCK1/2 pathway. Moreover, activating Piezo1 can induce epithelial dysfunction.

Anatomical Resection Improves Disease-Free Survival After Lung Metastasectomy of Colorectal Cancer.

PURPOSE: This study aimed to evaluate the role of anatomical resection (AR) in lung metastasectomy (LM) of colorectal cancer (CRC) and to investigate clinically relevant prognostic factors. PATIENTS AND METHODS: The medical records of 350 consecutive patients who underwent LM of CRC from 2011 to 2019 were reviewed. The patients were designated into AR group (lobectomy and segmentectomy), and non-anatomical resection (NAR) group (wedge resection), respectively. Kaplan-Meier method was used to analyze disease-free survival (DFS), pulmonary-specific disease-free survival (PDFS) and overall survival (OS). Cox proportional hazards regression model was performed to analyze the factors associated with DFS, PDFS and OS. RESULTS: A total of 92 (31.2%) patients were enrolled in AR group and 203 (68.8%) in non-anatomical resection (NAR) group. AR significantly improved the 3-year DFS (64.1% vs 46.8%, HR 0.587, 95% CI 0.397-0.867, P = 0.007) and PDFS (75.0% vs 60.1%, HR 0.565, 95% CI 0.356-0.899, P = 0.016) compared with NAR. However, the extent of resection did not significantly impact the 3-year OS (AR 92.4% vs NAR 85.7%, HR 0.511, 95% CI 0.224-1.165, P = 0.110). In multivariate analysis, AR was identified as a protective factor for DFS (HR 0.576, 95% CI 0.356-0.934, P = 0.025) and PDFS (HR 0.631, 95% CI 0.409-0.973, P = 0.037). Preoperative abnormal CA19-9 was identified as the only prognostic factor for OS. CONCLUSION: AR was superior to NAR for DFS and PDFS after LM from CRC.

Gastroenterologists Reveal More Digestive Symptoms in COVID-19 Patients than Nongastroenterologists in Fever Clinic.

The incidence of digestive symptoms may vary depending on doctors' professional backgrounds when they inquired suspected COVID-19 patients in a fever clinic. We sought to understand the characteristics of inquiries about digestive symptoms by doctors in different specialties; therefore, inquiry records of 2 gastroenterologists and 6 nongastroenterologists were reviewed. We compared the difference in inquiry of digestive symptoms (diarrhea, vomit, distension, anorexia, and abdominal pain) between these two groups among identified COVID-19 patients. And we further compared the difference of digestive symptoms between confirmed patients and suspected cases who excluded from COVID-19. Among 495 confirmed COVID-19 cases (254 cases by gastroenterologists and 241 cases by nongastroenterologists), 22.83% patients experienced various digestive symptoms in the gastroenterologists' group, while only 4.47% reported digestive symptoms by nongastroenterologists (p < 0.0001). Additionally, among initially suspected 611 patients who presented with similar respiratory symptoms inquired by gastroenterologists, confirmed cases presented far more frequency of digestive symptoms than excluded cases (22.8% vs. 3.64%, p < 0.0001). Furthermore, confirmed patients reported more percentage of watery diarrhea (56% vs. 36%, p < 0.0001) and higher frequent vomit (2.77 ± 0.97 vs. 1.80 ± 0.45 per day, p = 0.041) than excluded cases. We concluded that gastroenterologists could detect a greater proportion of gastrointestinal symptoms in COVID-19 patients during fever clinic inquiries. Moreover, confirmed COVID-19 patients are more likely to have higher severity in digestive symptoms than excluded cases. Therefore, physicians in fever clinic should pay more attention to the triage of gastrointestinal symptoms.

Resveratrol activates DNA damage response through inhibition of polo-like kinase 1 (PLK1) in natural killer/T cell lymphoma.

BACKGROUND: Extranodal natural killer/T cell lymphoma (NKTCL) is a highly aggressive non-Hodgkin lymphoma with a poor prognosis. Resveratrol (REV), a natural nontoxic pleiotropic agent, has antitumor effects, yet not being studied in NKTCL. METHODS: We performed immunohistochemical (IHC) staining with NKTCL tumor tissues. Apoptosis and cell cycle of NKTCL cell line NK-92 were detected by using flow cytometry. Then we detected the cellular expression level of polo-like kinase 1 (PLK1) and key molecules in DNA damage response (DDR) pathway by using RNA sequencing (RNA-seq) technology, real-time PCR, and Western blot. RESULTS: In this study, we found distinguishingly expressed phosphorylated ataxia telangiectasia mutated (ATM) in human NKTCL tumor tissues compared to normal lymph nodes samples. But low levels of phosphorylated checkpoint kinase 2 (Chk2) and phosphorylated p53 were shown, suggesting that DDR pathway is blocked midway in NKTCL. REV inhibited the proliferation of NK-92 cells in a time- and dose-dependent manner, arrested cell cycle at G1 phase, and induced mitochondrial apoptosis. PLK1 was inhibited in both mRNA and protein levels by REV in NK-92 cells. At the same time, phosphorylation levels of Chk2 and p53 were upregulated. CONCLUSIONS: DDR pathway plays an important role in the pathogenesis of NKTCL. REV shows anti-NKTCL activity. The inhibition of PLK1 and the activation of DDR are vital for REV induced tumor cell apoptosis.

Antitumor effects of icaritin and the molecular mechanisms.

Traditional Chinese Medicine (TCM) has been increasingly studied for antitumor activities. Icaritin, a hydrolytic product of icariin, is an effective ingredient of the traditional Chinese herb epimedium with multiple pharmacological activities. Among them, the antitumor activity of icaritin has been widely studied and reported in tumors both in vitro and in vivo. While its exact antitumor mechanisms await revelation, icaritin has been found to regulate several key molecules and pathways concerning cell fate, including CDK-dependent pathways, mitogen-activated protein kinases (MAPKs), the serine-threonine kinase AKT, signal transducer and activator of transcription 3 (STAT3), and p53. The ability to induce cellular oxidative stress also contributes to its antitumor activity. This review outlines the results of key investigations focusing on the antitumor effects and mechanisms of icaritin.

Short and narrow flag leaf1, a GATA zinc finger domain-containing protein, regulates flag leaf size in rice (Oryza sativa).

BACKGROUND: The flag leaf of rice (Oryza sativa L.) is an important determinant of plant type characteristics and grain yield. Identification of flag leaf mutants of rice is crucial to elucidate the molecular mechanism of flag-leaf development, and for exploitation of rice germplasm resources. RESULTS: In this study, we describe a mutant designated short and narrow flag leaf 1 (snfl1). Histological analysis showed that the length of epidermal cells and number of longitudinal veins were decreased in the flag leaf of the snfl1 mutant. Map-based cloning indicated that a member of the GATA family of transcription factors is a candidate gene for SNFL1. A single-nucleotide transition at the last base in the single intron of snfl1 led to variation in alternative splicing and early termination of translation. Complemented transgenic plants harbouring the candidate SNFL1 gene rescued the snfl1 mutant. Analysis of RT-PCR and the SNFL1 promoter by means of a GUS fusion expression assay showed that abundance of SNFL1 transcripts was higher in the culm, leaf sheath, and root. Expression of the SNFL1-GFP fusion protein in rice protoplasts showed that SNFL1 was localized in nucleus. CONCLUSIONS: We conclude that SNFL1 is an important regulator of leaf development, the identification of which might have important implications for future research on GATA transcription factors.

The miR-17-92 cluster/QKI2/ß-catenin axis promotes osteosarcoma progression.

Quaking(QKI) is an RNA binding protein, and it has been shown to serve as a tumor suppressor. However, the expression and functions of QKI in osteosarcoma progression remain poorly understood. In this study, we aimed to explore the expression of QKI2 in osteosarcoma tissues and to determine the mechanisms underlying aberrant QKI2 expression and the effect of QKI2 on osteosarcoma progression. We found that QKI2 was significantly down-regulated in osteosarcoma tissues compared with adjacent normal bone tissues. Using a series of molecular biological techniques, we demonstrated that all members of the miR-17-92 cluster were up-regulated and contributed to the down-regulation of QKI2 expression in osteosarcoma. Functional examination showed that QKI2 inhibited the proliferation, migration and invasion of osteosarcoma cells via decreasing the expression of ß-catenin. Conclusively, we revealed that the regulatory axis consisting of the miR-17-92 cluster/QKI2/ß-catenin plays a crucial role in the development and progression of osteosarcoma.

Piezo2: A Candidate Biomarker for Visceral Hypersensitivity in Irritable Bowel Syndrome?

BACKGROUND/AIMS: Currently, there exists no biomarker for visceral hypersensitivity in irritable bowel syndrome (IBS). Piezo proteins have been proven to play an important role in the mechanical stimulation to induce visceral pain in other tissues and may also be a biomarker candidate. The aim of this study was to test the expressions of Piezo1 and Piezo2 proteins in the intestinal epithelial cells from different intestinal segments and to explore the correlation between Piezo proteins expression and visceral pain threshold. METHODS: Post-infectious IBS was induced in mice via a Trichinella spiralis infection. Visceral sensitivity was measured with abdominal withdrawal reflex to colorectal distention. Inflammation in the small intestine and colon was scored with H&E staining. Expression location of Piezo proteins was confirmed by immunohistochemistry. Abundance of Piezo proteins were measured with real-time reverse transcriptase polymerase chain reaction. RESULTS: Piezo1 and Piezo2 proteins were expressed in the intestinal epithelial cells. The expression levels of Piezo1 and Piezo2 were abundant in the colon than the small intestine (P < 0.001 for Piezo1, P = 0.003 for Piezo2). Expression of Piezo2 in the colon significantly correlated to the visceral sensitivity (r = -0.718, P = 0.001) rather than the mucosal inflammation. CONCLUSION: Piezo2 is a candidate biomarker for visceral hypersensitivity in IBS.