Machine learning-based screening and validation of liver metastasis-specific genes in colorectal cancer.

Colorectal liver metastasis (CRLM) is challenging in the clinical treatment of colorectal cancer. Limited research has been conducted on how CRLM develops. RNA sequencing data were obtained from the Gene Expression Omnibus (GEO) and The Cancer Genome Atlas (TCGA). Four machine learning algorithms were used to screen the hub CRLM-specific genes, including Least Absolute Shrinkage and Selection Operator (Lasso), Random forest, SVM-RFE, and XGboost. The model for identifying CRLM was developed using stepwise logistic regression and was validated using internal and independent datasets. The prognostic value of hub CRLM-specific genes was assessed using the Lasso-Cox method. The in vitro experiments were performed using SW620 cells. The CRLM identification model was developed based on four CRLM-specific genes (SPP1, ZG16, P2RY14, and PRKAR2B), and the model efficacy was validated using GSE41258 and three external cohorts. Five CRLM-specific prognostic hub genes, SPP1, ZG16, P2RY14, CYP2E1, and C5, were identified using the Lasso-Cox algorithm, and a risk score was constructed. The risk score was validated using the GSE39582 cohort. Three genes have both efficacy in identifying CRLM and prognostic value: ZG16, P2RY14, and SPP1. Immune infiltration and enrichment analyses demonstrated that SPP1 was associated with M2 macrophage polarization and extracellular matrix remodeling. In vitro experiments indicated that SPP1 may act as a cancer-promoting factor. The hub CRLM-specific gene SPP1 can help determine the diagnosis, prognosis, and immune infiltration of patients with CRLM.

HNF1ɑ promotes colorectal cancer progression via HKDC1-mediated activation of AKT/AMPK signaling pathway.

The hepatocyte nuclear factor-1 (HNF1ɑ) is a transcription factor that contributes to several kinds of cancer progression. However, very little is known regarding the mechanisms underlying the activity of HNF1ɑ. We aimed to explore the role of HNF1ɑ in the progress of colorectal cancer (CRC) and elucidate its molecular mechanism. HNF1ɑ expression was upregulated in CRC samples and high expression of HNF1ɑ was associated with poor prognosis of CRC patients. HNF1α knockdown and overexpression inhibited and promoted proliferation, migration and invasion of CRC cells both in vitro and in vivo respectively. Mechanistically, HNF1ɑ increased the transcriptional activity of hexokinase domain component 1（HKDC1）promoter, thus activated AKT/AMPK signaling. Meanwhile, HKDC1 upregulation was important for the proliferation, migration and invasion of CRC cells and knockdown of HKDC1 significantly reversed the proliferation, migration and invasion induced by HNF1α overexpression. Taken together, HNF1ɑ contributes to CRC progression and metastasis through binding to HKDC1 and activating AKT/AMPK signaling. Targeting HNF1ɑ could be a potential therapeutic strategy for CRC patients.

Robot-assisted laparoscopic combined with endoscopic partial gastrectomy (RALE-PG) for the treatment of gastric gastrointestinal stromal tumors in challenging anatomical locations: single-center experience.

Background: Gastric gastrointestinal stromal tumors in challenging anatomical locations are difficult to remove. Methods: This study retrospectively analyzed the clinical data of 12 patients with gastric GISTs in challenging anatomical locations who underwent robot-assisted laparoscopic combined with endoscopic partial gastrectomy (RALE-PG) and manual suturing of the gastric wall. Results: This study included 12 patients with a mean age of 56.8 ± 9.8 years and a mean BMI of 23.9 ± 1.9 kg/m2. Tumors were located in the GEJ (n = 3), lesser curvature (n = 3), posterior gastric wall (n = 3) and antrum (n = 3). The cardia and pylorus were successfully preserved in all patients regardless of the tumor location. The mean tumor size was 4.5 ± 1.4 cm. The mitotic-count/50 mm2 was less than 5 in all patients (100%). There was no intraoperative tumor rupture (0%) and no conversion to open surgery (0%). The median operation time was 122 (97-240) min, and the median blood loss volume was 10 (5-30) ml. The median postoperative VAS score was 2 (2-4). The median time to first flatus was 2 (2-3) days. The median time to first fluid intake was 2 (2-3) days. The median time to first ambulation after the operation was 3 (2-4) days. No cases of anastomotic stenosis or leakage were found. The median time to drain removal for 6 patients was 5 (4-7) days. The median time to nasogastric tube removal for all patients was 2 (1-5) days. The median postoperative hospital stay was 5 (4-8) days. One patient (female/41 year) developed moderate anemia (Clavien-Dindo grade II complication). There was no unplanned readmission within 30 days after the operation. The median distance from the tumor to the resection margin was 1 (1-2) cm. R0 resection was achieved in all patients. The median follow-up period was 19 (10-25) months, and all patients survived with no recurrence or metastasis. Conclusions: RALE-PG is a safe, feasible and advantageous technique for treating GISTs in challenging anatomical locations. It can be used to accurately remove the tumor while preserving gastric function to the greatest extent, but long-term oncologic outcomes need to be evaluated in a study with a larger sample size and longer follow-up period.

Robotic natural orifice specimen extraction surgery versus robotic transabdominal specimen extraction surgery for early-stage rectal cancer: a multicenter propensity score-matched analysis (in China).

BACKGROUND: Despite the global increase in the adoption of robotic natural orifice specimen extraction surgery (R-NOSES), its advantages over robotic transabdominal specimen extraction surgery (R-TSES) for treating early-stage rectal cancer remain debated. There is scant nationwide, multicenter studies comparing the surgical quality and short-term outcomes between R-NOSES and R-TSES for this condition. OBJECTIVE: This retrospective cohort study was conducted nationally across multiple centers to compare the surgical quality and short-term outcomes between R-NOSES and R-TSES in early-stage rectal cancer. DESIGN: Multicenter retrospective cohort trial. SETTING: Eight experienced surgeons from 8 high-volume Chinese colorectal cancer treatment centers. PATIENTS: The study included 1086 patients who underwent R-NOSES or R-TSES from October 2015 to November 2023 at the 8 centers. Inclusion criteria were: (1) histologically confirmed rectal adenocarcinoma; (2) robotic total mesorectal excision; (3) postoperative pathological staging of TisN0M0 or T1-2N0M0; (4) availability of complete surgical and postoperative follow-up data. Patients were matched 1:1 in the R-NOSES and R-TSES groups using the propensity score matching (PSM) technique. RESULTS: After PSM, 318 matched pairs with well-balanced patient characteristics were identified. The operation time for the R-NOSES group was significantly longer than that for the R-TSES group [140 min (125-170 min) vs. 140 min (120-160 min), P = 0.032]. Conversely, the times to first flatus and initial oral intake in the R-NOSES group were significantly shorter than those in the R-TSES group [48 h (41-56 h) vs. 48 h (44-62 h), P = 0.049 and 77 h (72-94 h) vs. 82 h (72-96 h), P = 0.008], respectively. Additionally, the length of postoperative hospital stay was shorter in the R-NOSES group compared with the R-TSES group [7 day (7-9 day) vs. 8 day (7-9 day), P = 0.005]. The overall postoperative complication rates were similar between the groups (10.7% in the R-NOSES group vs. 11.9% in the R-TSES group, P = 0.617). However, the R-NOSES group had a lower incidence of wound complications compared to the R-TSES group (0.0% vs. 2.2%, P = 0.015). Regarding surgical stress response, the R-NOSES group showed superior outcomes. Additionally, patients in the R-NOSES group required fewer additional analgesics on postoperative days 1, 3, and 5 and reported lower pain scores compared to the R-TSES group. The body image scale (BIS) and cosmetic scale (CS) scores were also significantly higher in the R-NOSES group. Furthermore, the R-NOSES group demonstrated significantly better outcomes in functional dimensions such as physical, role, emotional, social, and cognitive functioning, and in symptoms like fatigue and pain, when compared to the R-TSES group. LIMITATIONS: It is imperative to ensure the safe and standardized implementation of R-NOSES through the establishment of a uniform training protocol. CONCLUSIONS: These results affirm that R-NOSES is a safe and effective treatment for early-stage rectal cancer when meticulously executed by skilled surgeons.

Correlation Analysis Between Tumor Deposit and Clinicopathologic Characteristics and Prognosis of Gastric Cancer: A Multicenter Retrospective Study.

BACKGROUND: The mechanism underlying the formation of gastric tumor deposits (TDs) is unclear. We aimed to explore the risk factors for the formation and prognostic value of TDs. METHODS: This retrospective analysis included 781 locally advanced gastric cancer (LAGC) patients from four medical institutions in China, from June 2014 to June 2018. The risk factors for TD formation and prognostic value were determined through univariate and multivariate analyses. RESULTS: Univariate analysis revealed that TD positivity was closely related to tumor diameter, Borrmann classification, differentiation degree, pT stage, pN stage, pTNM stage, and nerve and vascular invasion (p < 0.05). Multivariate logistic regression revealed that tumor diameter ≥ 5 cm (odds ratio [OR] 1.836, 95% confidence interval [CI] 1.165-2.894, p = 0.009) and vascular invasion (OR 2.152, 95% CI 1.349-3.433, p = 0.001) were independent risk factors for TD positivity. Multivariate Cox analysis revealed that TD positivity (OR 1.533, 95% CI 1.101-2.134, p = 0.011), tumor diameter ≥ 5 cm (OR 1.831, 95% CI 1.319-2.541, p < 0.001), pT4a stage (OR 1.652, 95% CI 1.144-2.386, p = 0.007), and vascular invasion (OR 1.458, 95% CI 1.059-2.008, p = 0.021) were independent risk factors for GC prognosis. The 5-year overall and disease-free survival of the TD-positive group showed significant effects among patients in the pT4a and pN3b stages (p < 0.05). CONCLUSIONS: TDs are closely related to tumor diameter and vascular invasion in LAGC patients, and TD positivity is an independent prognostic factor for LAGC patients, especially those at pT4a and pN3b stages.

Activin A/ACVR2A axis inhibits epithelial-to-mesenchymal transition in colon cancer by activating SMAD2.

Colorectal cancer is one of the most common malignancies worldwide. Liver metastasis is the major direct cause of colorectal cancer-related deaths. Although radical resection is the most effective treatment for colorectal cancer liver metastasis, several patients are not eligible for surgery. Therefore, there is a need to develop novel treatments based on the understanding of the biological mechanisms underlying liver metastasis in colorectal cancer. This study demonstrated that activin A/ACVR2A inhibits colon cancer cell migration and invasion, as well as suppresses the epithelial-to-mesenchymal transition of mouse colon cancer cells. This finding has been further validated in animal experiments. Mechanistic studies revealed that activin A binds to Smad2 (instead of Smad3) and activates its transcription. Analysis of the paired clinical samples further confirmed that the expression levels of ACVR2A and SMAD2 were the highest in adjacent healthy tissues, followed by primary colon cancer tissues and liver metastasis tissues, suggesting that ACVR2A downregulation may promote colon cancer metastasis. Bioinformatics analysis and clinical studies demonstrated that ACVR2A downregulation was significantly associated with liver metastasis and poor disease-free and progression-free survival of patients with colon cancer. These results suggest that the activin A/ACVR2A axis promotes colon cancer metastasis by selectively activating SMAD2. Thus, targeting ACVR2A is a potential novel therapeutic strategy to prevent colon cancer metastasis.

Clinical value of the platelet and inflammatory factor activation in vascular endothelial injury in essential hypertension.

OBJECTIVE: To investigate the clinical value of platelet and inflammatory factor activation in vascular endothelial injury in hypertension. METHODS: A total of 120 hypertension patients diagnosed in our hospital from December 2019 to June 2021 were enrolled as study objects (Hypertension group); besides, another cohort of 60 healthy people undergoing physical examination at the same period were recruited as the controls (Control group). Next, the baseline clinical characteristics of subjects in the two groups were recorded and compared. Specifically, a hematology analyzer was adopt for detecting the mean platelet volume (MPV), platelet distribution width (PDW) and platelet hematocrit (PCT); ELISA for the level of IL-6, IL-8 and TNF-α; PHILIPS EPIQ 7 C (a device assessing endothelial vasodilator function in a non-invasive fashion) for reactive hyperemia index (RHI); univariate and multivariate regression analysis for risk factors triggering endothelial dysfunction; and Spearman correlation analysis for the correlation of platelet activation indicators and inflammatory factor level with vascular endothelial function. RESULTS: Compared with the Control group, the patients in the Hypertension group exhibited higher levels of MPV, PDW, PCT, inflammatory factors (IL-6, IL-8 and TNF-α) and lower RHI. Moreover, Spearman correlation analysis showed a significant negative correlation of MPV, PDW, PCT, IL-6, IL-8 and TNF-α level with RHI level. In addition, univariate and multivariate regression analysis presented that MPV, PCT, IL-8 and TNF-α were risk factors for vascular endothelial dysfunction. CONCLUSION: The activation of platelet and inflammatory factor is closely related to vascular endothelial function injury in patients with hypertension. To be specifically, platelet and inflammatory factor activation can effectively reflect the vascular endothelial function injury in patients with hypertension and has high clinical value.

Can an incomplete ERAS protocol reduce postoperative complications compared with conventional care in laparoscopic radical resection of colorectal cancer? A multicenter observational cohort and propensity score-matched analysis.

Background: The patients undergoing laparoscopic radical colorectomy in many Chinese hospitals do not achieve high compliance with the ERAS (enhanced recovery programs after surgery) protocol. Methods: The clinical data from 1,258 patients were collected and divided into the non-ERAS and incomplete ERAS groups. Results: A total of 1,169 patients were screened for inclusion. After propensity score-matched analysis (PSM), 464 pairs of well-matched patients were generated for comparative study. Incomplete ERAS reduced the incidence of postoperative complications (p = 0.002), both mild (6.7% vs. 10.8%, p = 0.008) and severe (3.2% vs. 6.0%, p = 0.008). Statistically, incomplete ERAS reduced indirect surgical complications (27,5.8% vs. 59, 12.7) but not local complications (19,4.1% vs. 19, 4.1%). The subgroup analysis of postoperative complications revealed that all patients benefited from the incomplete ERAS protocol regardless of sex (male, p = 0.037, 11.9% vs. 17.9%; female, p = 0.010, 5.9% vs. 14.8%) or whether neoadjuvant chemotherapy was administered (neoadjuvant chemotherapy, p = 0.015, 7.4% vs. 24.5%; no neoadjuvant chemotherapy, p = 0.018, 10.2% vs. 15.8%). Younger patients (<60 year, p = 0.002, 7.6% vs. 17.5%) with a low BMI (<22.84, 9.4% vs. 21.1%, p < 0.001), smaller tumor size (<4.0 cm, 8.1% vs. 18.1%, p = 0.004), no fundamental diseases (8.8% vs. 17.0%, p = 0.007), a low ASA score (1/2, 9.7% vs. 16.3%, p = 0.004), proximal colon tumors (ascending/transverse colon, 12.2% vs. 24.3%, p = 0.027), poor (6.1% vs. 23.7%, p = 0.012)/moderate (10.3% vs. 15.3%, p = 0.034) tumor differentiation and no preoperative neoadjuvant radiotherapy (10.3% vs. 16.9%, p = 0.004) received more benefit from the incomplete ERAS protocol. Conclusion: The incomplete ERAS protocol decreased the incidence of postoperative complications, especially among younger patients (<60 year) with a low BMI (<22.84), smaller tumor size (<4.0 cm), no fundamental diseases, low ASA score (1/2), proximal colon tumors (ascending/transverse colon), poor/moderate differentiation and no preoperative neoadjuvant radiotherapy. ERAS should be recommended to as many patients as possible, although some will not exhibit high compliance. In the future, the core elements of ERAS need to be identified to improve the protocol.

An insight into planarian regeneration.

BACKGROUND: Planarian has attracted increasing attentions in the regeneration field for its usefulness as an important biological model organism attributing to its strong regeneration ability. Both the complexity of multiple regulatory networks and their coordinate functions contribute to the maintenance of normal cellular homeostasis and the process of regeneration in planarian. The polarity, size, location and number of regeneration tissues are regulated by diverse mechanisms. In this review we summarize the recent advances about the importance genetic and molecular mechanisms for regeneration control on various tissues in planarian. METHODS: A comprehensive literature search of original articles published in recent years was performed in regards to the molecular mechanism of each cell types during the planarian regeneration, including neoblast, nerve system, eye spot, excretory system and epidermal. RESULTS: Available molecular mechanisms gave us an overview of regeneration process in every tissue. The sense of injuries and initiation of regeneration is regulated by diverse genes like follistatin and ERK signaling. The Neoblasts differentiate into tissue progenitors under the regulation of genes such as egfr-3. The regeneration polarity is controlled by Wnt pathway, BMP pathway and bioelectric signals. The neoblast within the blastema differentiate into desired cell types and regenerate the missing tissues. Those tissue specific genes regulate the tissue progenitor cells to differentiate into desired cell types to complete the regeneration process. CONCLUSION: All tissue types in planarian participate in the regeneration process regulated by distinct molecular factors and cellular signaling pathways. The neoblasts play vital roles in tissue regeneration and morphology maintenance. These studies provide new insights into the molecular mechanisms for regulating planarian regeneration.

The CD133+CXCR4+ Colorectal Tumor Cells Promote Colorectal Cancer Progression by PI3K/AKT Signaling.

Colorectal cancer (CRC) is one of the most common cancers in the world. Due to its preferential metastasis to the liver, CRC has become one of the leading causes of cancer-related deaths worldwide. There has evidence showing that a variety of subpopulations exist among cancer cells, which play an important role in liver metastasis. Growing evidence suggests that CD133 and C-X-C chemokine receptor type 4 (CXCR-4) are thought to contribute to cancer progression and metastasis. However, it has not been fully characterized in CRC. Here, we found that the expression of CD133 and CXCR4 in metastatic liver cancer tissues was higher than that of the primary tumor tissue and paratumor tissue. Furthermore, CD133+CXCR4+ cells were found to contribute to colorectal carcinogenesis and liver metastasis in vitro and in vivo. Moreover, CXCR4 blocked significantly inhibited the CD133+CXCR4+ cells metastatic to the liver in a mouse model. We also showed that CD133+CXCR4+ induced significant phosphorylation of PI3K/AKT. In conclusion, our data demonstrate that CD133+CXCR4+ cell subsets play an important role in the development and progression of colon cancer.

IGHG1 upregulation promoted gastric cancer malignancy via AKT/GSK-3ß/ß-Catenin pathway.

BACKGROUND: Despite current advances in gastric cancer treatment, disease metastasis and chemo-resistance remain as major hurdles against better overall prognosis. Previous studies indicated that IGHG1 as well as -Catenin serve as important regulators of tumor cellular malignancy. Therefore, understanding detailed molecular mechanism and identifying druggable target will be of great potentials in future therapeutic development. METHODS: Surgical tissues and gastric cancer cell lines were retrieved to evaluate IGHG1 expression for patients with or without lymph node/distal organ metastasis. Functional assays including CCK8 assay, Edu assay, sphere formation assay and transwell assay, wound healing assay, etc. were subsequently performed to evaluate the impact of IGHG1/-catenin axis on tumor cell proliferation, migration and chemo-resistance. RESULTS: Gastric cancer tissues and tumor cell lines demonstrated significantly higher level of IGHG1. Functional study further demonstrated that IGHG1 promoted proliferative and migration as well as chemo-resistance of gastric cancer tumor cells. Further experiments indicated that IGHG1 activated AKT/GSK-3/-Catenin axis, which played crucial role in regulation of proliferative and chemo-resistance of gastric cancer cells. CONCLUSION: This study provided novel evidences that IGHG1 acted as oncogene by promotion of gastric cancer cellular proliferation, migration and chemo-resistance. Our research further suggested that IGHG1/AKT/GSK-3ß/ß-Catenin axis acted as novel pathway which regulated gastric cancer cellular malignant behavior. Our research might inspire future therapy development to promote overall prognosis of gastric cancer patients.

Cost-effectiveness analysis of a community-based colorectal cancer screening program in Shanghai, China.

OBJECTIVE: This study investigated the cost-effectiveness of a community-based colorectal cancer-screening program (C-CRCSP) in Shanghai, China, among the residents in the urban, suburban and rural areas. METHODS: A Markov model was constructed to evaluate the cost-effectiveness of a 25-year annual C-CRCSP including 100 000 populations. Cost-effectiveness was determined by the incremental cost-effectiveness ratio (ICER); referring to either life-years gained, or quality-adjusted life-years (QALYs) gained. The threshold was gross domestic product per capita. Univariate and multivariate sensitivity analyses were performed to investigate the influence of compliance, prevalence, technological performance, medical cost and annual cost discount rate (3.5%) on ICER. A probabilistic sensitivity analysis evaluated the probability of the cost-effectiveness of C-CRCSP at different maximum acceptable ceiling ratios. RESULTS: Compared with no screening, the C-CRCSP resulted in total gains of 7840 QALYs and 2210 life-years (LY), at a total cost of CNY 58.54 million; that is, the ICER were CNY 7460/QALYs and CNY 26650/LY. Stratifying by residency, the cumulative gains in QALYs and LY were estimated to be the lowest in the urban populations compared with the rural and suburban populations. The cost for the urban population was 3-fold and 6-fold that of the suburban and rural populations. The ICER for QALYs ranged from 2180 (rural) to 16 840 (urban). CONCLUSION: The cost-effectiveness of a C-CRCSP in Shanghai was most favorable for the rural population, while the urban population benefits less in terms of QALYs. ICER could be enhanced by measures that increase compliance.

Effect of hematopoietic progenitor cells on the biological characteristics of colon cancer tumor stem cells.

BACKGROUND: Cancer stem cells (CSCs) are a type of tumor cell that are self-sustaining and can differentiate into several different types of cells. The present study aims to investigate the effect of hematopoietic progenitor cells (HPCs) on the biological behavior of colon CSCs (CCSCs) and to determine the underlying molecular mechanisms of liver metastasis in colorectal cancer. METHODS: Subsets of CCSCs were isolated from stem-like HCT116 cells and cocultured with CD133+ HPCs in vitro. Colony formation assay, and CCK-8 were used to assess the effects of HPCs on CCSC subsets. Invasive and migration assay were done to study the effects of HPCs mediated metastatic capacity of CCSC subsets. Expression of MMP-9, VEGF, E-cadherin and ß-catenin was analyzed by qPCR and Western blotting. RESULTS: CCK-8 and colony formation assays showed that HPCs significantly promoted proliferation and colony formation of the CCSC subsets (P=0.031). HPCs also significantly enhanced the migration (P=0.011) and invasive capacity (P=0.001) of the CCSC subsets. Quantitative PCR showed that MMP-9 and VEGF expression in CCSC subsets were significantly upregulated (P=0.000 and P=0.005). Western blotting showed that MMP-9, VEGF and ß-catenin expression in CCSC subsets were significantly upregulated (P=0.000, P=0.005, P=0.000). The protein expression levels of E-cadherin in the CCSC subsets was significantly downregulated (P=0.002). CONCLUSIONS: CD133+ HPCs enhanced migration, invasion and proliferation of CCSC subsets in vitro.

Author Correction: Single-cell RNA-seq highlights intra-tumoral heterogeneity and malignant progression in pancreatic ductal adenocarcinoma.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Single-cell RNA-seq highlights intra-tumoral heterogeneity and malignant progression in pancreatic ductal adenocarcinoma.

Pancreatic ductal adenocarcinoma (PDAC) is the most common type of pancreatic cancer featured with high intra-tumoral heterogeneity and poor prognosis. To comprehensively delineate the PDAC intra-tumoral heterogeneity and the underlying mechanism for PDAC progression, we employed single-cell RNA-seq (scRNA-seq) to acquire the transcriptomic atlas of 57,530 individual pancreatic cells from primary PDAC tumors and control pancreases, and identified diverse malignant and stromal cell types, including two ductal subtypes with abnormal and malignant gene expression profiles respectively, in PDAC. We found that the heterogenous malignant subtype was composed of several subpopulations with differential proliferative and migratory potentials. Cell trajectory analysis revealed that components of multiple tumor-related pathways and transcription factors (TFs) were differentially expressed along PDAC progression. Furthermore, we found a subset of ductal cells with unique proliferative features were associated with an inactivation state in tumor-infiltrating T cells, providing novel markers for the prediction of antitumor immune response. Together, our findings provide a valuable resource for deciphering the intra-tumoral heterogeneity in PDAC and uncover a connection between tumor intrinsic transcriptional state and T cell activation, suggesting potential biomarkers for anticancer treatment such as targeted therapy and immunotherapy.

METTL3-mediated m6A modification is required for cerebellar development.

N6-methyladenosine (m6A) RNA methylation is the most abundant modification on mRNAs and plays important roles in various biological processes. The formation of m6A is catalyzed by a methyltransferase complex including methyltransferase-like 3 (METTL3) as a key factor. However, the in vivo functions of METTL3 and m6A modification in mammalian development remain unclear. Here, we show that specific inactivation of Mettl3 in mouse nervous system causes severe developmental defects in the brain. Mettl3 conditional knockout (cKO) mice manifest cerebellar hypoplasia caused by drastically enhanced apoptosis of newborn cerebellar granule cells (CGCs) in the external granular layer (EGL). METTL3 depletion-induced loss of m6A modification causes extended RNA half-lives and aberrant splicing events, consequently leading to dysregulation of transcriptome-wide gene expression and premature CGC death. Our findings reveal a critical role of METTL3-mediated m6A in regulating the development of mammalian cerebellum.

Negative lymph node count is a significant prognostic factor in patient with stage IV gastric cancer after palliative gastrectomy.

Negative lymph node (NLN) count has been validated as a protective predictor in various cancers after radical resection. However, the prognostic value of NLN count in the setting of stage IV gastric cancer patients who have received palliative resection has not been investigated. Surveillance, Epidemiology, and End Results Program (SEER)-registered gastric cancer patients were used for analysis in this study. Kaplan-Meier survival curves and multivariate Cox proportional hazards model were used to assess the risk factors for patients' survivals. The results showed that NLN count and N stage were independently prognostic factors in patients with stage IV gastric cancer after palliative surgery (P< 0.001). X-tile plots identified 2 and 11 as the optimal cutoff values to divide the patients into high, middle and low risk subsets in term of cause-specific survival (CSS). And NLN count was proved to be an independently prognostic factor in multivariate Cox analysis (P< 0.001). The risk score of NLN counts demonstrated that the plot of hazard ratios (HRs) for NLN counts sharply increased when the number of NLN counts decreased. Collectively, our present study revealed that NLN count was an independent prognostic predictor in stage IV gastric cancer after palliative resection. Standard lymph node dissection, such as D2 lymphadectomy maybe still necessary during palliative resection for patients with metastatic gastric cancer.

Transcriptome-Wide Identification and Prediction of miRNAs and Their Targets in Paris polyphylla var. yunnanensis by High-Throughput Sequencing Analysis.

Long dormancy period of seeds limits the large-scale artificial cultivation of the scarce Paris polyphylla var. yunnanensis, an important traditional Chinese medicine. Characterizing miRNAs and their targets is crucial to understanding the role of miRNAs during seed dormancy in this species. Considering the limited genome information of this species, we first sequenced and assembled the transcriptome data of dormant seeds and their seed coats as the reference genome. A total of 146,671 unigenes with an average length of 923 bp were identified and showed functional diversity based on different annotation methods. Two small RNA libraries from respective seeds and seed coats were sequenced and the combining data indicates that 263 conserved miRNAs belonging to at least 83 families and 768 novel miRNAs in 1174 transcripts were found. The annotations of the predicted putative targets of miRNAs suggest that these miRNAs were mainly involved in the cell, metabolism and genetic information processing by direct and indirect regulation patterns in dormant seeds of P. polyphylla var. yunnanensis. Therefore, we provide the first known miRNA profiles and their targets, which will assist with further study of the molecular mechanism of seed dormancy in P. polyphylla var. yunnanensis.

Effects of CO2 pneumoperitoneum on the expression of thymidine kinase 1 and Ki67 in colorectal carcinoma cells.

BACKGROUND: To investigate thymidine kinase 1(TK-1) and Ki67 expression levels of human colorectal carcinoma cells line SW480 after exposure to a simulated laparoscopic carbon dioxide (CO2) pneumoperitoneum environment at different pressures and lengths of exposure time. METHODS: The effects of the simulated laparoscopic CO2 pneumoperitoneum environment at different CO2 pressures (6, 9, 12, and 15 mmHg) and exposure times (2 and 4 h) on TK-1 and Ki67 of SW480 cells were assessed by flow cytometry and reverse transcription (RT-PCR). Cells cultured in a standard environment were used as the control group (at 37 °C, 5% CO2). RESULTS: In this study, TK-1 and Ki67 in SW480 cells tended to decrease with the increase of CO2 pressure and exposure time. Significantly lower expression levels were observed at 0 and 24 h of culture after exposure to both at 12 and 15 mmHg, as compared with the control group at 6 and 9 mmHg (p < 0.05). The expression of TK-1 and Ki67 levels increased up to a plateau of the control group after 48 and 72 h (p > 0.05). With the CO2 pneumoperitoneum exposure time prolonging, the expression of TK-1 and Ki67 levels in 12 or 15 mmHg was lower than in 2 h (p < 0.05). In the same exposure time, the transcription level of TK-1 and Ki67 decreased significantly in 12 and 15 mmHg CO2 pneumoperitoneum groups (p < 0.05) and returned to the basal level of control group after being cultivated for 48 h (p > 0.05). In the same pressure, the difference of TK-1 mRNA between the groups of 2 and 4 h was also significant. CONCLUSION: The expression levels of TK-1 and Ki67 were suppressed temporarily after the continuous CO2 insufflation in higher pressure (at 12 and 15 mmHg). The higher the pressure of CO2 insufflation, the more the inhibiting effects of TK-1 and Ki67 will be. The longer the time of CO2 insufflation, the more significantly their expression decreased.

Inhibitory activity of chemical constituents from Arenaria serpyllifolia on nitric oxide production.

Five new compounds, including one new xanthone, 1-hydroxy-5-methoxyxanthone 6-O-ß-D-glucopyranoside (1), one new lignan, 3-(ß-D-glucopyranosyloxymethyl)-2-(4-hydroxy-3-methoxyphenyl)-5-(3-acetoxypropyl)-7-methoxy-(2R,3S)-dihydrobenzofuran (2), and three new γ-pyrones, japonicumone A 4'-O-ß-D-glucopyranoside (3), japonicumone B 3'-O-ß-D-glucopyranoside (4), and japonicumone B 4'-O-ß-D-glucopyranoside (5), together with eight known compounds (6-13) were isolated from the whole plants of Arenaria serpyllifolia. Their structures were elucidated on the basis of extensive spectroscopic analysis (UV, IR, HRESIMS, 1D- and 2D-NMR, and CD) as well as chemical methods. The isolated compounds were evaluated for their inhibitory effects on nitric oxide production in lipopolysaccharide-activated RAW 264.7 macrophages. Compounds 1-5, sacranoside A (9), and pedunculoside (13) showed potential nitric oxide inhibitory activities with IC50 values ranging from 14.92 µM to 52.23 µM.