Targeting TLK2 inhibits the progression of gastric cancer by reprogramming amino acid metabolism through the mTOR/ASNS axis.

Several recent studies have suggested that TLKs are related to tumor progression. However, the function and mechanism of action of TLK2 in gastric cancer (GC) remain elusive. In this study, TLK2 was found to be significantly upregulated in patients with GC and was identified as an independent prognostic factor for GC. Consistently, TLK2 knockdown markedly reduced the aggressiveness of GC, whereas its overexpression had the opposite effect. IP-MS revealed that the effects of TLK2 on GC were mainly associated with metabolism reprogramming. TLK2 knockdown suppressed amino acid synthesis by downregulating the mTORC1 pathway and ASNS expression in GC cells. Mechanistically, mTORC1 directly interacts with the ASNS protein and inhibits its degradation. Further experiments validated that the ASNS protein was degraded via ubiquitination instead of autophagy. Inhibiting and activating the mTORC1 pathway can upregulate and downregulate ASNS ubiquitination, respectively, and the mTORC1 pathway can reverse the regulatory effects of TLK2 on ASNS. Furthermore, TLK2 was found to regulate the mRNA expression of ASNS. TLK2 directly interacted with ATF4, a transcription factor of ASNS, and promoted its expression. The kinase inhibitor fostamatinib significantly inhibited the proliferative, invasive, and migratory capabilities of GC cells by inhibiting TLK2 activity. Altogether, this study reveals a novel functional relationship between TLK2 and the mTORC1/ASNS axis in GC. Therefore, TLK2 may serve as a potential therapeutic target for GC.

Dissecting the genetic and microenvironmental factors of gastric tumorigenesis in mice.

Gastric cancer (GC) is one of the most frequent and lethal malignancies in the world. However, our understanding of the mechanisms underlying its initiation and progression is limited. Here, we generate a series of primary GC models in mice with genome-edited gastric organoids, which elucidate the genetic drivers for sequential transformation from dysplasia to well-differentiated and poorly differentiated GC. Further, we find that the orthotopic GC, but not the subcutaneous GC even with the same genetic drivers, display remote metastasis, suggesting critical roles of the microenvironment in GC metastasis. Through single-cell RNA-seq analyses and functional studies, we show that the interaction between fibronectin 1 on stomach-specific macrophages and integrin a6ß4 on GC cells promotes remote metastases. Taken together, our studies propose a strategy to model GC and dissect the genetic and microenvironmental factors driving the full-range gastric tumorigenesis.

Analysis of bowel function, urogenital function, and long-term follow-up outcomes associated with robotic and laparoscopic sphincter-preserving surgical approaches to total mesorectal excision in low rectal cancer: a retrospective cohort study.

OBJECTIVE: The present study comparatively analyzed short-term clinical effectiveness and long-term follow-up endpoints associated with robotic-assisted sphincter-preserving surgery (RAS) and laparoscopic-assisted sphincter-preserving surgery (LAS) when used to treat low rectal cancer. METHOD: Within such a single-center retrospective cohort analysis, low rectal cancer patients that underwent RAS (n=200) or LAS (n=486) between January 2015 and beginning of July 2018 were enrolled. RESULTS: The mean operative durations in the RAS and LAS cohorts were 249±64 min and 203±47 min, respectively (P<0.001). Temporary ileostomy rates in the RAS and LAS cohorts were 64.5% and 51.6% (P = 0.002). In addition, major variations across such cohorts regarding catheter removal timing, time to liquid intake, time to first leaving bed, and length of hospitalization (all P<0.001). This distal resection margin distance within the RAS cohort was diminished in comparison to LAS cohort (P=0.004). For patients within the LAS cohort, the time required to recover from reduced urinary/female sexual function was > 6 months post-surgery (P<0.0001), whereas within the RAS cohort this interval was 3 months (P<0.0001). At 6 months post-surgery, male sexual function within RAS cohort was improved in comparison to LAS cohort (P<0.001). At 6 months post-surgery, Wexner scores revealed similar results (P<0.001). No major variations within overall or disease-free survival were identified across these cohorts at 3 or 5 years post-surgery. CONCLUSION: Robotic sphincter-preserving surgery is a safe and effective surgical technique in low rectal patients in terms of postoperative oncological safety and long-term endpoints. And the RAS strategy provides certain additional benefits with respect to short-term urogenital/anorectal functional recovery in treated patients compared to LAS.

Application of Laparoscopic Gastric Jejunum Uncut Roux-en-Y Anastomosis.

Background: Uncut Roux-en-Y gastrojejunostomy, recently developed in China, is useful in the treatment of distal gastric cancer. This study is aimed at comparing laparoscopic gastric jejunum uncut Roux-en-Y anastomosis with conventional anastomosis in the surgical treatment of distal gastric malignancy. Methods: In this retrospective study, the clinical data of 178 patients and their follow-up records were analyzed. 112 cases (uncut group) were the observation group for stomach jejunum uncut Roux-en-Y anastomosis, the control group for the stomach, 66 cases (conventional group) were for jejunum Roux-en-Y anastomosis and Billroth I and Billroth II anastomosis. A comparison between the two groups was conducted based on the general situation of the patients, TNM stage, and one-year survival rate. Results: There was no significant difference reported between the two groups in terms of the general situation and TNM stage. A comparison on postoperative complications between the two groups revealed that the postoperative bleeding was 0.9% and 6.1%, the bile reflux gastritis was 1.8% and 9.1%, the anastomotic leakage was 0.0% and 3.0%, the delayed gastric emptying was 0.9% and 7.6%, and the overall complications was at 3.6% and 25.8%, which was significantly lower in the observation group than in the control group, and the difference was statistically significant. Notably, there was no significant difference in 1-year survival rate between the two groups. Conclusion: Laparoscopic gastric jejunal uncut Roux-en-Y anastomosis significantly reduces the risk of postoperative complications of the digestive tract. Its operation is easy and exhibits an effective curative effect.

The expression and diagnostic value of serum levels of EphA2 and VEGF-A in patients with colorectal cancer.

BACKGROUND: Several molecules are highly expressed in the serum of cancer patients, and can be used as serological markers. This approach has become one of the important auxiliary diagnostic methods for cancer. AIM: To investigate the correlation between the serum levels of EphA2 and VEGF-A and the pathogenesis of colorectal cancer (CRC) as well as the potential value of these molecules in the diagnosis of CRC. METHODS: ELISA was used to detect the levels of EphA2 and VEGF-A in the peripheral venous serum of 106 newly diagnosed patients with CRC and 69 normal controls. The relationship between the serum EphA2 and VEGF-A levels and the clinicopathological characteristics of CRC patients was analyzed. ROC analysis was used to investigate the diagnostic value of the serum EphA2 and VEGF-A levels in CRC, and the optimal cutoff value was calculated. RESULTS: The serum levels of EphA2 and VEGF-A in the CRC group were higher than those in the control as well as CEA, the serum level of EphA2 was positively correlated with the VEGF-A levels, but neither was significantly associated with the clinicopathological parameters of CRC. The ROC curve showed that the single index AUC was < 0.7 except for VEGF-A, and the accuracy of the combined diagnosis was higher than that of any other single index. The diagnosis scheme involving all three markers was the best (the sensitivity was 60.40%, the specificity was 92.8%, and the accuracy was 53.1%). The best critical values calculated were EphA2 > 297.92 ng/ml, EphA2 > 183.92 pg/ml and CEA > 5.19 ng/ml. CONCLUSION: The serum levels of EphA2 and VEGF-A are high in CRC patients, and the combine detection of CEA, EphA2 and VEGF-A can significantly improve the diagnostic accuracy of CRC.

Circ_0005927 Inhibits the Progression of Colorectal Cancer by Regulating miR-942-5p/BATF2 Axis.

BACKGROUND: Colorectal cancer (CRC) is one of the most common aggressive neoplasms worldwide. Circular RNAs (circRNAs) have been involved in the biological process of CRC. This study aimed to explore the effects of circ_0005927 on CRC progression and underneath mechanism. MATERIALS AND METHODS: The expression of circ_0005927, microRNA-942-5p (miR-942-5p) and basic leucine zipper ATF-like transcription factor 2 (BATF2) was detected by quantitative real time polymerase chain reaction (qRT-PCR). The protein expression of BATF2 was determined by Western blot. The effects among circ_0005927, miR-942-5p and BATF2 on cell colony-forming ability, apoptosis and migratory and invasive abilities were revealed by cell colony formation, flow apoptosis and transwell assays, respectively. The associated relationship between miR-942-5p and circ_0005927 or BATF2 was predicted by Circinteractome or TargetScan online database, and identified by dual-luciferase reporter or RNA immunoprecipitation (RIP) assay. The impacts of circ_0005927 overexpression on tumor growth in vivo were investigated by in vivo tumor formation assay. RESULTS: Circ_0005927 expression and the mRNA and protein expression of BATF2 were dramatically downregulated, while miR-942-5p expression was obviously upregulated in CRC tissues or cells compared with control groups. Circ_0005927 overexpression repressed cell colony-forming ability, migration and invasion, whereas induced cell apoptosis in CRC; however, these impacts were hindered by miR-942-5p mimic or BATF2 knockdown. Furthermore, circ_0005927 was a sponge of miR-942-5p, and miR-942-5p bound to BATF2. In addition, circ_0005927 overexpression repressed tumor growth in vivo. CONCLUSION: Circ_0005927 suppressed cell colony-forming ability, migration and invasion, and promoted cell apoptosis by sponging miR-942-5p to induce BATF2 in CRC. The possible mechanism provides a theoretical basis for the study of circRNA-directed therapy for CRC.

A novel method for π-shaped esophagojejunostomy and double-tract reconstruction (DTR) as an alternative in totally laparoscopic or robotic proximal gastrectomy for treating upper third proximal early gastric cancer.

This study evaluated the impact of a new intracorporeal π-shaped esophagojejunostomy (EJS) and double-tract reconstruction (DTR) in totally laparoscopic and totally robotic proximal gastrectomy (TLPG or TRPG) for treating upper third early gastric cancer (U-EGC) in terms of intraoperative and short-term postoperative outcomes. Early proximal gastric cancer patients were identified based on a prospectively established database. From January 2017 to December 2018, these patients underwent intracorporeal π-shaped EJS and DTR after totally laparoscopic (n = 8) or robotic (n = 4) proximal gastrectomy (PG). We recorded and analyzed the baseline characteristics and surgical outcomes, including postoperative complications for these patients. No severe postoperative complications were observed following the operational procedures. Twelve patients (seven male and five female) diagnosed with cardia cancer (Siewert II and III) were enrolled, of which eight underwent the totally laparoscopic proximal gastrectomy (TLPG), and four underwent the totally robotic proximal gastrectomy (TRPG). The mean operative time, blood loss, day of the start of the diet, and postoperative hospital stay was 235.54 ± 20.79 min, 50.65 ± 35.44 mL, 3.85 ± 0.65 days, and 12.45 ± 3.24 days, respectively. All patients presented with a diagnosis of stage I gastric cancer. The mean number of lymph node dissections and the maximum tumor diameter was 13.91 ± 4.63 and 2.18 ± 0.73 cm, respectively. After the operational procedure, using the iodoethylene contrast reagent, we observed that a large proportion of iodoethylene contrast agents entered the jejunum directly, and a small proportion entered the jejunum through the duodenum. Surgeons followed up with ten patients for more than 12 months and the remaining two patients for more than 24 months. None of the patients showed any signs of anastomotic stenosis or reflux esophagitis or anemia symptoms. This study presents a novel method for π-shaped EJS and DTR as an alternative in TLPG or TRPG for treating proximal early gastric cancer, and it offers better short-term postoperative and intraoperative surgical outcomes.

The Role of HER2 in Self-Renewal, Invasion, and Tumorigenicity of Gastric Cancer Stem Cells.

BACKGROUND: Deregulation of HER2 expression could affect the biological characteristics of gastric cancer cells and treatment option for gastric cancer patients. This research aims to investigate the impact of HER2 on biological characteristics of gastric cancer stem cells (GCSCs) and prognosis of gastric cancer patients. METHODS: HER2 knockdown in GCSCs were constructed by lentivirus transfection. Alterations of proliferation, self-renewal, invasion, migration, colony formation, and tumorigenicity of GCSCs were examined. The changes of gene expressions after HER2 interference in GCSCs were detected by gene microarray. The impact of concentration of serum HER2 and expression of HER2 in tumor tissues on survival of 213 gastric cancer patients was also analyzed. RESULTS: Down-regulation of HER2 decreased the self-renewal, colony formation, migration, invasion, proliferation, and chemotherapy resistance of GCSCs. However, the tumorigenicity of GCSCs in vivo was increased after down-regulation of HER2. The results of gene microarray showed that HER2 gene might regulate the signal transduction of mTOR, Jak-STAT, and other signal pathways and affect the biological characteristics of GCSCs. Furthermore, survival analyses indicated that patients with high concentration of HER2 in serum had a favorable overall survival. However, there was no significant correlation between expression of HER2 in tumor tissue and overall survival. CONCLUSION: Interference of HER2 in GCSCs decreased the capacity of self-renewal, proliferation, colony formation, chemotherapy resistance, invasion, and migration but might increase the tumorigenicity in vivo. Patients with high concentration of HER2 in serum seemed to have a favorable prognosis.

A case of COVID-19 patient with the diarrhea as initial symptom and literature review.

Since Dec 2019, a cluster of pneumonia outbreak in Wuhan, Hubei province, China, and soon spread to all province of China. The pathogen was proved to be a novel betacoronavirus called 2019 novel coronavirus (officially named by the World Health Organization as COVID-19). The typical clinical manifestations were fever, cough, dyspnea, and myalgia or fatigue. Less common symptoms included headache, diarrhea, nausea and vomiting. However diarrhea as the first symptom is rarely reported. Here we reported a case of 2019 novel coronavirus-infected patient (NCIP) with diarrhea as the initial symptom. Image of CT scan and laboratory examination and careful collected as well as detection of viral RNA in pharynx. The case demonstrate that gastrointestinal symptoms ware not rare in NCIP, and diarrhea could be the initial symptom.

Learning curve for gastric cancer patients with laparoscopy-assisted distal gastrectomy: 6-year experience from a single institution in western China.

Laparoscopy-assisted distal gastrectomy (LADG) is widely used for gastric cancer (GC) patients nowadays. This study aimed to investigate the time trend of outcomes so as to describe the learning curve for GC patients with LADG at a single medical institution in western China over a 6-year period.A total of 246 consecutive GC patients with LADG were divided into 5 groups (group A: 46 patients from 2006 to 2007; group B: 47 patients in 2008; group C: 49 patients in 2009; group D: 73 patients in 2010; and group E: 31 patients in 2011). All surgeries were conducted by the same surgeon. Comparative analyses were successively performed by Mann-Whitney U test or Student t test among the 5 different groups for the clinical data, including clinicopathologic characteristics, surgical parameters, postoperative course, and survival outcomes, through which the learning curve was described.There were no differences in the baseline information among the 5 groups (P > 0.05), and the proportion of advanced GC patients with LADG slightly increased from 58.7% to 77.4% during the 6 years. Besides, the proportion of D2/D2+ lymphadenectomy and the number of retrieved lymph nodes gradually grew from 60.9% to 80.6% and from 20.0 to 28.8, respectively. In addition, the operation time decreased from 299.2 to 267.8 minutes, while the estimated blood loss dropped from 175.2 to 146.8 mL. Furthermore, some surgical parameters (surgical duration and blood loss) and postoperative course (such as postoperative complications, the time to ambulation, to first flatus, and to first liquid intake as well as the length of hospital stay) were all observed to be significantly different between group A and other groups (P < 0.05), illustrating a similar downward trend and remaining stable to form a plateau after 46 cases in group A. However, no difference on overall survival was found among these 5 groups, and multivariate analysis indicated that factors, such as age, tumor differentiation, tumor size, and T stage as well as N stage, were independent prognostic factors for patients with LADG.Improvement on surgical parameters and postoperative course can be seen over the past years, and the cutoff value of the learning curve of LADG for surgeons with rich experience in open operation might be 46 cases.

Clinical significance of putative markers of cancer stem cells in gastric cancer: A retrospective cohort study.

Cancer stem cells (CSCs) are thought as the source of tumor maintaining and many CSCs markers have been identified. Regarding the heterogeneity in gastric cancer (GC), TNM stage is not enough to accurately predict the prognosis. The aim of this study was to investigate the clinical significance of CSCs markers (Lgr5, Oct4, CD133, EpCAM, CD54 and Sox2) and establish a new model based on these markers to accurately predict prognosis of GC. We retrospectively enrolled 377 GC tissues from January 2006 to October 2012 to perform immunohistochemistry (IHC), and 93 pairs of GC tissues and corresponding adjacent normal gastric tissues to perform quantitative PCR (qPCR) from December 2011 to October 2012. The clinicopathological and follow-up characteristics were collected. In IHC, Oct4, CD133 and EpCAM were independently related to tumor progression, while Sox2 were associated with well or moderate differentiation (all p<0.05). Cox regression showed that Oct4-EpCAM was an independently prognostic factor, indicating that double low expression of Oct4-EpCAM group had significantly better prognosis than control group (p=0.035). Regarding qPCR, CD133 was an independent prognostic factor, showing that the prognosis of patients with CD133 high expression was significantly worse than that of patients with CD133 low expression (p<0.001). The prognostic prediction accuracy of nomogram based on Oct4-EpCAM expression in IHC was significantly better than TNM stage alone (p=0.003). Low expressions of Oct4-EpCAM in IHC and CD133 in qPCR were favorable prognostic factors in GC. The nomogram based on Oct4-EpCAM was valuable in prognostic prediction of GC patients.

Clinical characteristics and prognostic factors of primary gastric lymphoma: A retrospective study with 165 cases.

Primary gastric lymphoma (PGL) is the most common extranodal non-Hodgkin lymphoma. This retrospective study aimed to analyze the clinical characteristics, prognostic factors, and roles of different treatment modalities in patients with PGL.From January 2003 to November 2014, 165 patients who were diagnosed with PGL at West China Hospital were enrolled in this study. The clinical features, treatment, and follow-up information were analyzed.In this study, diffuse large B-cell lymphoma (DLBCL) (108, 65.5%) and mucosa-associated lymphoid tissue (MALT) lymphoma (52, 31.5%) were two predominant histological subtypes. One-year and 5-year overall survival (OS) rates of all patients were 95.2% and 79.5%, respectively; in whom 110 (66.7%) underwent surgery, 110 (66.7%) received chemotherapy, 12 (7.3%) received radiotherapy, and 10 (6.1%) received Helicobacter pylori eradication. And 75 patients (45.5%) were treated with at least 2 different types of therapies. Elevated lactic dehydrogenase (LDH) levels, poor performance status (PS), advanced stage, International Prognostic Index (IPI) score ≥3, conservative treatment, and high-grade histological subtype were associated with worse prognosis in univariate analysis. Cox regression analysis showed that LDH levels, PS, staging, and histological subtype were independent predictors of survival outcomes. In the DLBCL type, 5-year OS was significantly better in the surgically treated group (80.1%) than that of patients conservatively treated (49.8%) (P = 0.001). Surgical treatment had almost no impact on OS in the MALT type than conservative treatment (P = 0.597). The proportion of patients received conservative treatment increased from 4.5% in period 1 to 51.7% in period 4.High LDH levels, poor PS, advanced staging, and malignant pathological type at diagnosis are significantly associated with poor OS. Our data suggest that surgery is superior in prognosis over conservative treatment in the DLBCL type, but not in the MALT type. Recently, conservative treatment is becoming more preferred approach in patients with PGL.

A new predictive model combined of tumor size, lymph nodes count and lymphovascular invasion for survival prognosis in patients with lymph node-negative gastric cancer.

BACKGROUND: Various factors may affect the clinical prognosis of lymph node-negative gastric cancer (GC) patients. This study aimed to provide evaluable prognostic information of combination of tumor size (Ts), lymph nodes count (LNs) and lymphovascular invasion (LVI) in lymph node-negative GC patients. METHODS: A total of 1,019 node-negative GC patients were enrolled in this retrospective study from 2000 to 2010. The cutoff points of Ts and LNs were determined using X-tile and patients were randomly categorized into training and validation sets by the sample size ratio 1:1. The clinicopathologic characteristics were analyzed and survival prognostic factors were identified, whereas the survival prediction accuracy was also compared by C-index during the different independent prognostic factors. RESULTS: The cutoff points for Ts were 3cm and 5cm, while 14 was the cutoff point for LNs. Age, T stage, Ts, LNs and LVI were identified as independent prognostic factors in node-negative GC patients, and a new prognostic predictive model, TsNL staging system which was composed of Ts, LNs and LVI, was proposed in this study. Compared with T staging system, significant improvement of predictive accuracy for TsNL system was found. Furthermore, nomogram based on TsNL was more accurate in prognostic prediction than that based on Ts, LNs and LVI, separately. CONCLUSIONS: Age, T stage, Ts, LNs and LVI were independent prognostic factors in lymph node-negative GC patients. The TsNL staging system, composed of Ts, LNs and LVI, which was closely associated with clinicopathologic features, may improve the prognostic prediction accuracy in node-negative GC patients.

A nomogram composed of clinicopathologic features and preoperative serum tumor markers to predict lymph node metastasis in early gastric cancer patients.

Predicting lymph node metastasis (LNM) accurately is of great importance to formulate optimal treatment strategies preoperatively for patients with early gastric cancer (EGC). This study aimed to explore risk factors that predict the presence of LNM in EGC. A total of 697 patients underwent gastrectomy enrolled in this study, were divided into training and validation set, and the relationship between LNM and other clinicopathologic features, preoperative serum combined tumor markers (CEA, CA19-9, CA125) were evaluated. Risk factors for LNM were identified using logistic regression analysis, and a nomogram was created by R program to predict the possibility of LNM in training set, while receiver operating characteristic (ROC) analysis was applied to assess the predictive value of the nomogram model in validation set. Consequently, LNM was significantly associated with tumor size, macroscopic type, differentiation type, ulcerative findings, lymphovascular invasion, depth of invasion and combined tumor marker. In multivariate logistic regression analysis, factors including of tumor size, differentiation type, ulcerative findings, lymphovascular invasion, depth of invasion and combined tumor marker were demonstrated to be independent risk factors for LNM. Moreover, a predictive nomogram with these independent factors for LNM in EGC patients was constructed, and ROC curve demonstrated a good discrimination ability with the AUC of 0.847 (95% CI: 0.789-0.923), which was significantly larger than those produced in previous studies. Therefore, including of these tumor markers which could be convenient and feasible to obtain from the serum preoperatively, the nomogram could effectively predict the incidence of LNM for EGC patients.

Superiority of lymph node ratio-based staging system for prognostic prediction in 2575 patients with gastric cancer: validation analysis in a large single center.

This study aimed to evaluate the prognostic significance of node ratio (Nr), the ratio of metastatic to retrieved lymph nodes, and to investigate whether a modified staging system based on Nr can improve prognostic ability for gastric cancer patients following gastrectomy. A total of 2572 patients were randomly divided into training set and validation set, and the cutoff points for Nr were produced using X-tile. The relationships between Nr and other clinicopathologic factors were analyzed, while survival prognostic discriminatory ability and accuracy were compared among different staging systems by AIC and C-index in R program. Patients were categorized into four groups as follows: Nr0, Nr1: 0.00-0.15, Nr2: 0.15-0.40 and Nr3: > 0.40. Nr was significantly associated with clinicopathologic factors including macroscopic type, tumor differentiation, lymphovascular invasion, perineural invasion, tumor size, T stage, N stage and TNM stage. Besides, for all patients, Nr and TNrM staging system showed a smaller AIC and a larger C-index than that of N and TNM staging system, respectively. Moreover, in subgroup analysis for patients with retrieved lymph nodes < 15, Nr was demonstrated to have a smaller AIC and a larger C-index than N staging system. Furthermore, in validation analysis, Nr, categorized by our cutoff points, showed a larger C-index and a smaller AIC value than those produced in previous studies. Nr could be considered as a reliable prognostic factor, even in patients with insufficient (< 15) retrieved lymph nodes, and TNrM staging system may improve the prognostic discriminatory ability and accuracy for gastric cancer patients undergoing radical gastrectomy.