Insight into immune checkpoint inhibitor therapy for colorectal cancer from the perspective of circadian clocks.

Colorectal cancer (CRC) is one of the most common malignant tumours and the third most common cause of cancer deaths worldwide, with high morbidity and mortality. Circadian clocks are widespread in humans and temporally regulate physiologic functions to maintain homeostasis. Recent studies showed that circadian components were strong regulators of the tumour immune microenvironment (TIME) and the immunogenicity of CRC cells. Therefore, insight into immunotherapy from the perspective of circadian clocks can be promising. Although immunotherapy, especially immune checkpoint inhibitor (ICI) treatment, has been a milestone in cancer treatment, greater accuracy is still needed for selecting patients who will respond positively to immunotherapy with minimal side effects. In addition, there were few reviews focusing on the role of the circadian components in the TIME and the immunogenicity of CRC cells. Therefore, this review highlights the crosstalk between the TIME in CRC and the immunogenicity of CRC cells based on the circadian clocks. With the goal to achieve the possibility that patients with CRC can benefit most from the ICI treatment, we provide potential evidence and a novel idea for building a predictive framework combined with circadian factors, searching for enhancers of ICIs targeting circadian components and clinically implementing the timing of ICI treatment for patients with CRC.

BMAL1 induces colorectal cancer metastasis by stimulating exosome secretion.

BACKGROUND: To adapt to daily changes in the external environment, organisms have developed circadian rhythm systems with a period of approximately 24 h. Many studies have reported that both circadian rhythms and exosomes play important roles in the development and metastasis of tumors. However, whether circadian clock genes can affect the progression of tumors by regulating exosomes remains unclear. METHODS AND RESULTS: In this study, we isolated exosomes from the supernatant of human colorectal cancer (CRC) cells, including SW480, SW620, and HCT116 cells, by differential centrifugation and characterized exosomes by transmission electron microscopy, nanoparticle tracking analysis, and Western blot analysis. Then, we found that exosomes derived from SW480, SW620 and HCT116 cells could promote the migration of HCT116 and human umbilical vein endothelial cells. Exosomes derived from SW620 cells showed increased stimulating effects when we increased the expression of BMAL1, a core circadian protein. In contrast, exosomes derived from SW480 and HCT116 cells showed decreased stimulating effects when we knocked down the expression of BMAL1. Furthermore, we discovered that BMAL1 promotes the release of exosomes by HCT116 and SW620 cells. In addition, by luciferase assay, we confirmed that BMAL1 transcriptionally regulates the expression of Rab27a, a key molecule related to the secretion of exosomes. CONCLUSIONS: Our data reveal a new mechanism by which BMAL1 induces CRC metastasis by stimulating exosome secretion. This finding may help further clarify the role of circadian rhythm in the progression of CRC.

The safety and feasibility of intra-corporeal gastroduodenostomy using a self-pulling and latter transected method (Delta SPLT) in totally laparoscopic distal gastrectomy.

BACKGROUND AND OBJECTIVES: In 2016, the self-pulling and latter transection method (named "Delta SPLT"), a modified delta-shaped gastroduodenostomy (DA) technique for totally laparoscopic distal gastrectomy, was described. Delta SPLT reduced the technical difficulty of the surgery and the quantity of cartridges required with a manageable initial safety profile. Here, the safety and feasibility of this technique are analyzed at 1 year's follow-up. METHODS: The demographic and clinicopathologic profiles, perioperative details, and postoperative outcomes of 45 consecutive patients who underwent Delta SPLT from March 2016 to March 2019 were retrospectively analyzed. The Delta SPLT technique, which consisted of one endoscopic linear stapler and four cartridges each, was used for reconstruction in every case. RESULTS: The mean operative time was 127.1 ± 38.2 min, including a reconstruction duration of 22.6 ± 7.2 min. There were no surgical or anastomotic complications. The mean postoperative stay duration was 5.8 ± 1.2 days, and the morbidity rate was 2.2% with one case of postoperative pneumonia. CONCLUSIONS: The results at the one-year follow-up suggest that Delta SPLT is a safe and feasible procedure. Delta SPLT is characterized by fewer difficulties experienced during surgery, lower surgical costs, it is easy to practice, and it is beneficial for patients who are undergoing gastroduodenostomy.

A novel method of self-pulling and latter transected delta-shaped Billroth-I anastomosis in totally laparoscopic distal gastrectomy.

BACKGROUND: We developed a modified delta-shaped gastroduodenostomy technique in totally laparoscopic distal gastrectomy. This novel technique, which effectively reduces the required quantity of linear stapler [1-3], was named as self-pulling and latter transected delta-shaped anastomosis (Delta SPLT) [4]. METHODS: Delta SPLT was performed on 15 patients with stage cT1-2 antral cancer. We ligated the duodenum with a rope instead of transecting it and used the ligature rope to pull the duodenum during the whole progress of gastroduodenostomy. When closing the entry hole, the duodenum was transected at the same time, which saved one linear stapler. Data of clinicopathologic characteristics, surgical and postoperative outcomes were collected and expressed as means ± standard deviations. RESULTS: All the operations were successfully performed by using no more than four 60-mm linear staplers. The mean BMI of the patients is 23.0 ± 2.5 kg/m2 (range 17.0-26.0 kg/m2), and duration of the operation was 115.0 ± 33.4 min (range 75-215 min), including 22.3 ± 6.7 min (range 15-35 min) of reconstruction. Mean blood loss was 82.7 ± 71.3 mL (range 10-300 mL), and mean times to first flatus was 2.3 ± 1.1 days (range 1-5 days). A mean number of 27.5 ± 5.4 (range 18-38) lymph nodes was retrieved. Overall postoperative morbidity rate was 6.7% (1/15). There was no anastomosis-related complication, but one case of pneumonia developed on postoperative day (POD) 2 which was successfully managed by conservative methods. Patients were discharged (POD mean 5.8 ± 1.3, range 4-9) when their bowel movements recovered and no discomfort with soft diet was claimed. CONCLUSION: Delta SPLT is a safe and feasible technique and requires less clinical costs.

A novel method of self-pulling and latter transected reconstruction in totally laparoscopic total gastrectomy: feasibility and short-term safety.

BACKGROUND: This study depicts a novel reconstruction method of self-pulling and latter transection (SPLT) in totally laparoscopic total gastrectomy (TLTG) and evaluates its feasibility and short-term safety by comparing its surgical and postoperative outcomes with the conventional TLTG. PATIENTS AND METHODS: Forty patients with gastric cancer from June 2014 to December 2015 received SPLT-TLTG. Data of clinicopathologic characteristics, surgical and postoperative outcomes, and follow-up findings in SPLT cases were collected and retrospectively compared with those of conventional TLTG to clarify the clinical benefits. RESULTS: The mean duration of the operation was 179.5 ± 37.7 min in SPLT-TLTG, including 23.2 ± 8.8 min of reconstruction; both were significantly shorter than the conventional TLTG (P = 0.030; P < 0.001). There were no significant differences in blood loss, time of the first flatus and postoperative hospital stays between two groups. SPLT-TLTG developed no complication beyond the conventional TLTG. CONCLUSION: SPLT-TLTG is safe, feasible and minimally invasive. It may serve as a promising procedure for gastric cancer that helps to expand the indication of TLTG to cases with even high level of tumor invasion and requires less in both surgical skills and clinical costs.

A novel method of delta-shaped intracorporeal double-tract reconstruction in totally laparoscopic proximal gastrectomy.

BACKGROUND: The purpose of this study is to depict a novel delta-shaped intracorporeal double-tract reconstruction (DT) for totally laparoscopic (TL) proximal gastrectomy (PG), and to evaluate its safety and feasibility by analyzing its surgical and postoperative outcomes. PATIENTS AND METHODS: We retrospectively reviewed the cases of 21 patients who underwent TLPG and TLDT (TLPG-DT) from January to December 2014 in our hospital. The data of clinicopathologic characteristics, surgical and postoperative outcomes, and follow-up findings were collected and analyzed. RESULTS: The mean duration of the operation was 173.8 ± 21.8 min, including 27.8 ± 5.3 min of reconstruction. The blood loss was 109.2 ± 96.3 mL. The mean number of LNs dissected was 25.7 ± 4.7. The mean time of the first flatus was at postoperative day 2.3 ± 1.0, and the mean postoperative hospital stay was 6.8 ± 2.5 days. The early complications rate was 9.5 %, including one intraperitoneal hemorrhage and one pulmonary infection (both were managed through conservative methods and no re-operation occurred). The rate of complications in late stage was also 9.5 %, including one diarrhea and one reflux symptom claim. Among the total 21 cases, 17 patients were followed up more than 6 months, showing no signs of reflux esophagitis or anastomotic stenosis. The mean weight loss in 3 and 6 months after the operation was 4.3 and 5.7 %, respectively. CONCLUSION: Totally laparoscopic delta-shaped intracorporeal double-tract reconstruction is a safe, feasible and minimally invasive reconstruction method with excellent postoperative outcomes in terms of preventing reflux esophagitis and anastomotic stenosis. TLPG-DT might serve as a promising treatment for proximal gastric cancer of early stage.

Clock upregulates intercellular adhesion molecule-1 expression and promotes mononuclear cells adhesion to endothelial cells.

Clock is a basic helix-loop-helix (bHLH) transcription factor that plays important role in circadian rhythms of various physiological functions. Previous study showed that the expression of intercellular adhesion molecule-1 (ICAM-1) was reduced in the liver tissues of Clock mutant mice. However, how Clock regulates ICAM-1 expression and whether Clock affects cell adhesion function remain unknown. In the present study, we found that exogenous expression of Clock upregulated the gene expressions of ICAM-1 and other adhesion-related genes including VCAM1 and CCL-2, and increased the transcriptional activity of ICAM-1 in mouse brain microvascular endothelial cell lines. In contrast, loss of Clock decreased these gene expressions and ICAM-1 transcriptional activity. Chromatin immunoprecipitation (ChIP) assay revealed that Clock binds to the E-box-like enhancer of ICAM-1 gene. ICAM-1 gene showed rhythmic expression in endothelial cells after serum shock in vitro, suggesting ICAM-1 may be a Clock-controlled gene. Clock regulates the adhesion of mononuclear cells to endothelial cells via ICAM-1. Together, our findings show that Clock is a positive regulator of ICAM-1, and promotes the adhesion of mononuclear cells to endothelial cells.

The safety and feasibility assessment of overlap esophagojejunostomy with self-pulling and latter transection technique in totally laparoscopic total gastrectomy.

BACKGROUND: This study presented an innovative technique in totally laparoscopic total gastrectomy (TLTG) for overlap esophagojejunostomy (E-J), termed self-pulling and latter transection (SPLT) (overlap SPLT). It evaluated the effectiveness and short-term outcomes of this novel method through a comparative analysis with the established functional end-to-end (FETE) E-J incorporating SPLT. METHODS: From September 2018 to September 2023, this study enrolled 68 patients with gastric cancer who underwent TLTG with overlap SPLT anastomosis and 120 patients who underwent TLTG with FETE SPLT anastomosis. Clinicopathologic characteristics and surgical and postoperative outcomes data for overlap SPLT cases were gathered and retrospectively compared with those from FETE SPLT TLTG to evaluate the effectiveness and clinical safety. RESULTS: The duration of anastomosis for overlap SPLT was 25.3 ± 7.4 minutes, significantly longer than that for the FETE SPLT (18.1 ± 4.0 minutes, P = .031). Perioperatively, 1 anastomosis-related complication occurred in each group, but this did not constitute a statistically significant difference (P = .682). No statistically significant differences were found between the 2 groups in terms of operative time, postoperative hospital stay, operative cost, surgical margins, or number of lymph nodes removed. Postoperative morbidity rates were similar between the groups (4.4% vs 5.8%, P = .676). CONCLUSION: The overlap SPLT technique is regarded as a safe and feasible method for anastomosis. There were no apparent differences in complications between overlap SPLT and FETE SPLT, but overlap SPLT costed 1 additional stapler cartridge and required a longer duration.

Effect of H2S on the circadian rhythm of mouse hepatocytes.

BACKGROUND: Dysregulation of circadian rhythms can contribute to diseases of lipid metabolism. NAD-dependent deacetylase sirtuin-1(SIRT1) is an important hub which links lipid metabolism with circadian clock by its deacetylation activity depends on intracellular NAD+/NADH content ratio. Hydrogen sulfide (H2S) is an endogenous reductant which can affect the intracellular redox state. Therefore, we hypothesized that exogenous H2S can affect the expression of circadian clock genes mediated by sirt1 thereby affecting body's lipid metabolism. And also because the liver is a typical peripheral circadian clock oscillator that is intimately linked to lipid metabolism. Thus the effect of H2S were observed on 24-hour dynamic expression of 4 central circadian clock genes and sirt1gene in primary cultured hepatocytes. RESULTS: We established a hepatocyte model that showed a circadian rhythm by serum shock method. And detected that the expression level and the peak of circadian clock genes decreased gradually and H2S could maintain the expression and amplitude of circadian clock genes such as Clock, Per2, Bmal1 and Rev-erbαwithin a certain period time. Accordingly the expression level of sirt1 in H2S group was significantly higher than that in the control group. CONCLUSION: Exogenous reductant H2S maintain the circadian rhythm of clock gene in isolated liver cells. We speculated that H2S has changed NAD+/NADH content ratio in hepatocytes and enhanced the activity of SIRT1 protein directly or indirectly, so as to maintain the rhythm of expression of circadian clock genes, they play a role in the prevention and treatment of lipid metabolism-related disease caused by the biological clock disorders.

Effect of different oesophagojejunostomy methods on the quality of life of gastric cancer patients after totally laparoscopic total gastrectomy with self-pulling and latter transected technique: study protocol for a randomised trial.

INTRODUCTION: Gastric cancer is the fifth most common cancer worldwide and the detection rate of proximal gastric cancer has been increasing. Currently, surgical resection using gastrectomy and proper perigastric lymphadenectomy is the only treatment option to enhance the survival rate of patients with gastric cancer. Laparoscopic total gastrectomy (LTG) is increasingly performed for adenocarcinoma of the oesophagogastric junction. However, totally LTG (TLTG) is only performed by a few surgeons due to difficulty associated with oesophagojejunostomy (OJ), in which there is no consensus on a standardised anastomosis technique. We propose a randomised trial to compare functional end-to-end anastomosis (FETE) and side-to-side anastomosis (Overlap) for OJ. METHODS AND ANALYSIS: A prospective, randomised, open-label, single-centre, interventional trial has been designed to evaluate the quality of life (QoL) outcomes and safety of FETE and Overlap, with a 1-year follow-up as the primary endpoint. The trial began in 2020 and is scheduled to enrol 96 patients according to a previous sample size calculation. Patients were randomly allocated to the FETE or Overlap groups with a follow-up of 1 year to assess QoL after the procedure. All relevant clinical data including biological markers were collected. The primary indicator is the D-value between the postoperative and preoperative QoL. Student's t-tests will be used to compare continuous variables, while χ2 tests or Fisher's exact tests will be used to compare categorical variables. Statistical analysis will be performed with SPSS V.23.0 statistical software. A p<0.05 will be considered statistically significant. ETHICS AND DISSEMINATION: This study has been approved by the Hospital Institutional Review Board of Huashan Hospital, Fudan University (2020-1055). The results will be submitted for publication in peer-reviewed journals. TRIAL REGISTRATION NUMBER: ChiCTR2000035583.

Genome-wide CRISPR Screening Reveals Pyrimidine Metabolic Reprogramming in 5-FU Chronochemotherapy of Colorectal Cancer.

Objective: Disruption of the circadian rhythm is associated with cancer occurrence, response to chemotherapy, and poor prognosis. Thus, using internal clock-based chronotherapy to optimize the administration time may improve the therapeutic effects of anticancer drugs while reducing the side effects. Chronotherapy with 5-fluorouracil (5-FU) has been observed in colorectal cancer (CRC) for a long time, but its effect is under controversial and the mechanism remains unclear. Methods: Genome-wide clustered regularly interspaced short palindromic repeats (CRISPR) screening and RNA-sequencing were combined to identify the potential genes or pathways involved in 5-FU chronochemotherapy. Genetic deletion or overexpression of pyrimidine metabolic pathway genes were conducted to examine cellular viability with or without 5-FU via flow cytometry. Western blotting, qPCR, chromatin immunoprecipitation, gain-of-function and loss-of-function assays of several CRC cell lines in vitro and in vivo were used to elaborate and validate the mechanism of 5-FU chronotherapeutic effects. Results: Chronochemotherapeutic effects of 5-FU on CRC in vivo were verified. Furthermore, 5-FU chronochemotherapy related genes such as UPP2, UCK2 and UMPS in the pyrimidine metabolic pathway were identified. Disturbance in these genes, especially UMPS, perturbs 5-FU treatment outcomes in CRC cells. Mechanistically, the core circadian gene, brain and muscle aryl hydrocarbon receptor nuclear translocator-like protein-1 (BMAL1), extensively regulate gene expression in pyrimidine metabolic pathway by binding to E-box element in the promoter region of key genes such as UMPS and perturb their enzymatic activities, thereby maintain diurnal efficacy of 5-FU in CRC cells. Conclusion: This study uncovered a new mechanism by which a core circadian gene BMAL1 increases the effectiveness of 5-FU by enhancing the expression and enzymatic activities of key genes in the pyrimidine metabolic pathway in CRC cells. The findings suggest a novel strategy for CRC chemotherapy by targeting chrono-modulated genes of the 5-FU metabolic pathway.

Expression of circadian clock gene human Period2 (hPer2) in human colorectal carcinoma.

BACKGROUND: Recent studies have shown that disruption of circadian rhythms is one of the tumor promoting factors which contribute to mammalian cancer development and progression, but very little is known about the molecular changes of circadian genes in colorectal carcinoma (CRC). Thus, in this study, changes in the expression of human Period2 (hPer2), one of the key circadian clock regulators, in CRC and its correlation with prognosis were investigated. METHODS: Immunohistochemical (IHC) staining and real-time PCR for hPer2 were performed for 38 CRC cases. RESULTS: IHC analysis detected positive staining for hPer2 in 81.6% (31/38) of CRC tissues and 97.4% (37/38) of surrounding non-cancerous tissues (P < 0.05). Most colorectal cells in non-cancerous tissues were homogeneously stained. In contrast, in the paired cancerous tissues, a heterogeneous pattern was found with a significant portion of cancer cells displaying negative or weak hPer2 staining. In over 60% cases (24/38), the staining for hPer2 was much stronger in non-cancerous cells than in the paired cancerous cells. Well-differentiated cancer cells are more likely to maintain hPer2 expression than poorly-differentiated ones. Furthermore, associations of decreased hPer2 levels with patients' age, histological grade, TNM stage and expression of nucleus proliferation related antigen: Ki67 were also detected (P < 0.05). Expression of hPer2 did not correlate with that of either p53 or C-erB-2. Similar to hPer2 protein expression, quantitative RT-PCR for hPer2 also showed decreased mRNA expression in CRC. CONCLUSION: These results suggest a role for hPer2 in normal colorectal cell function and the potential deregulation of hPer2 expression in the development, invasion, and metastasis of CRC.

Postnatal ontogenesis of clock genes in mouse suprachiasmatic nucleus and heart.

BACKGROUND: The master clock within the hypothalamic suprachiasmatic nucleus (SCN) synchronizing clocks in peripheral tissues is entrained by the environmental condition, such as the light-dark (LD) cycle. The mechanisms of circadian clockwork are similar in both SCN and peripheral tissues. The aim of the present work was to observe the profiles of clock genes expression in mouse central and peripheral tissues within postnatal day 5 (P5). The daily expression of four clock genes mRNA (Bmal1, Per2, Cry1 and Rev-erb alpha) in mouse SCN and heart was measured at P1, P3 and P5 by real-time PCR. RESULTS: All the studied mice clock genes began to express in a circadian rhythms manner in heart and SCN at P3 and P5 respectively. Interestingly, the daily rhythmic phase of some clock genes shifted during the postnatal days. Moreover, the expressions of clock genes in heart were not synchronized with those in SCN until at P5. CONCLUSION: The data showed the gradual development of clock genes in SCN and a peripheral tissue, and suggested that development of clock genes differed between in the SCN and the heart. Judging from the mRNA expression, it was possible that the central clock synchronized the peripheral clock as early as P5.

Clinicopathological Characteristics and Prognostic Factors of Patients with Gastric Cancer Accompanying Neuroendocrine Differentiation (NEDGC).

AIM: Gastric carcinoma with neuroendocrine differentiation (NEDGC) is a relatively rare pathologic diagnosis in clinical practice, which has no specific guidelines or treatment recommendations yet. In this study, we aim to investigate the clinicopathological characteristics and prognostic factors of this disease. PATIENTS AND METHODS: We retrospectively analyzed clinicopathological data from a series of 82 NEDGC patients who underwent surgery for gastrectomy at Huashan Hospital Fudan University between January 2007 and December 2018. Furthermore, a series of 50 cases were used to analyze 3-year overall survival (OS). RESULTS: Ages of the patients ranged from 26 to 83 years (M:F, 4.8:1). The majority of patients suffered from some symptoms (97.6%), as the most common one was abdominal pain (48.8%). Most of the tumors were ≥5 cm (53.7%), in the lower part of the stomach (47.5%), and with advanced T (87.8% ≥T3) and N (67.1% ≥N1) stage. As to the neuroendocrine markers, Syn showed a slight advantage on sensitivity than CgA (79.3 and 75.6%, respectively). The 3-year OS was 54%. Advanced T stage (≥T3) of the primary tumor, positive lymphovascular invasion (LVI), large tumor size (5.5cm), high neutrophil-to-lymphocyte ratio (NLR, 2.51), and low prealbumin level (173.87 mg/L) were associated with inferior OS based on the univariate analysis. Low preoperative hemoglobin level (113.87g/L), laparoscopic-assisted gastrectomy, and advanced N stage (N3) were three independent risk factors for 3-year OS of NEDGC patients in both univariate and multivariate analysis. CONCLUSION: The TN staging system for gastric adenocarcinoma also has a prognostic value for NEDGC patients, while N3 stage works as an independent predictor of patients' survival. Since most of the NEDGC patients were in advanced stage, proper indications to perform operative laparoscopy should be selected.

Effect of hyperlipidemia on the expression of circadian genes in apolipoprotein E knock-out atherosclerotic mice.

BACKGROUND: Circadian patterns of cardiovascular vulnerability were well characterized, with a peak incidence of acute myocardial infarction and stroke secondary to atherosclerosis in the morning, which showed the circadian clock may take part in the pathological process of atherosclerosis induced by hyperlipidemia. Hence, the effect of hyperlipidemia on the expression of circadian genes was investigated in atherosclerotic mouse model. RESULTS: In apoE-/-mice on regular chow or high-fat diet, an atherosclerotic mouse model induced by heperlipidemia, we found that the peak concentration of serum lipids was showed four or eight hours later in apoE-/- mice, compared to C57BL/6J mice. During the artificial light period, a reduce in circulating level of serum lipids corresponded with the observed increase of the expression levels of some the transcription factors involved in lipid metabolism, such as PPARalpha and RXRalpha. Meanwhile, the expression of circadian genes was changed following with amplitude reduced or the peak mRNA level delayed. CONCLUSIONS: Our studies indicated that heperlipidemia altered both the rhythmicity and expression of circadian genes. Diet-induced circadian disruption may affect the process of atherosclerosis and some acute cardiovascular disease.

The circadian protein CLOCK regulates cell metabolism via the mitochondrial carrier SLC25A10.

Physiological function and metabolic regulation are the most important outputs of circadian clock controls in mammals. Mitochondrial respiration and ROS production show rhythmic activity. Mitochondrial carriers, which are responsible for mitochondrial substance transfer, are vital for mitochondrial metabolism. Clock (Circadian Locomotor Output Cycles Kaput) is the first core circadian gene identified in mammalian animals. However, whether CLOCK protein can regulate mitochondrial functions via mitochondrial carriers is unclear. Here, we showed that CLOCK can bind to the mitochondrial carrier SLC25A10. For further analysis, we established a Slc25a10-/--Hepa1-6 cell line using CRISPR/Cas9 gene-editing technology. Slc25a10-/--Hepa1-6 cells showed disordered glucose homeostasis, increased oxidative stress levels, and damaged electron transport chains. Next, using an immunoprecipitation assay, we found that amino acids 43-84 and 169-210 in SLC25A10 are key sites that respond to CLOCK binding. Finally, forced expression of wild-type SLC25A10 in Slc25a10-/--Hepa1-6 cells could compensate for the loss of SLC25A10; the decreased glucose metabolism, severe oxidative stress and damaged electron transport chain were recovered. In addition, a mutant Slc25a10 with changes in two key sites did not show a rescue effect. In conclusion, we identified a new protein-protein interaction mechanism in which CLOCK can directly regulate cell metabolism via the mitochondrial membrane transporter SLC25A10. Our study might provide some new insights into the relationship between circadian clock and mitochondrial metabolism.

Author Correction: 5-Hydroxymethylcytosine signatures in circulating cell-free DNA as diagnostic biomarkers for human cancers.

In the initial published version of this article, there was a mistake in the P value for the correlation between gene-expression changes and 5 hmC changes in tumors. The correct P value should be same as the P value shown in Fig. S6A: 9.8 × 10-6 (mistakenly shown as "9.8 × 106" in the main text). This correction does not affect the description of results or the conclusions of this study, since the range of P value is between 0 and 1.

[Safety evaluation on initial 100 consecutive procedures of self-pulling and latter transected esophagojejunostomy].

OBJECTIVE: To evaluate the feasibility and the short-term safety of self-pulling and latter transected esophagojejunostomy(SPLT) in totally laparoscopic total gastrectomy (TLTG). METHODS: One hundred patients with gastric cancer received TLTG-SPLT at General Surgery Department of Huashan Hospital (Fudan University) from June 2014 to January 2017(SPLT group). The clinicopathologic characteristics, surgical and postoperative outcomes were collected retrospectively and compared with the conventional group undergoing TLTG plus overlap or functional end-to-end anastomosis from October 2013 to December 2015. D2 lymph node dissection was regularly performed for all the patients. In SPLT group, a sterile hemp rope was held to ligate and drag down the esophagus to maintain "self-pulling" after the duodenum was transected by the first stapler, allowing the detachment of the posterior mediastinum. Then a hole 2-3 cm above the ligature rope was made on the right-posterior wall of the esophagus. When the mesenteric tension was checked, another hole was made at the anti-mesenteric border of the jejunum 20 cm distal to the ligament of Treitz. A side-to-side esophagojejunostomy (E-J) was then performed between the right-posterior wall of esophagus and the anti-mesenteric wall of the jejunum with the second linear stapler, forming an entry hole. The "latter transection" was applied with the third stapler inserted from the assistant's Trocar, which facilitated the esophagus and the afferent loop jejunum to be simultaneously transected above the level of the entry hole. After that, a side-to-side jejunojejunostomy(J-J) with another 2 staplers was carried out between the afferent loop stump and the Roux limb 40 cm below E-J, in which the E-J entry hole could also work as the entrance for the stapler. The TLTG-SPLT was therefore completed and the specimen was removed through the incision from the umbilical Trocar site. RESULTS: There were 66 male and 34 female patients in the SPLT group with median age of 64 years. The clinicopathologic baseline data of two groups were comparable(all P>0.05). All the patients underwent operations successfully, and none was converted to open surgery. No positive margin was found in either group. Mean operation duration was (178.2±35.9) minute in SPLT group, including (22.9±7.1) minute of reconstruction, which both were significantly shorter than those in conventional group [(204.4±55.8) minute, P=0.003; (30.5±7.2) minute, P=0.000]. Less blood loss [(74.3±72.5) ml vs. (104.2±71.6) ml, P=0.017] and earlier time to the first flatus [(1.9±1.6) days vs. (2.7±1.3) days, P=0.001] were observed in SPLT group. There were no significant differences in postoperative hospital stay and pathological findings between the two groups(all P>0.05). Postoperative operation-associated complications were found in 7 cases of SPLT group. Of these 7 patients, 1 case developed gastrointestinal bleeding, 3 pancreatic leakage, 2 chyle leakage, who all were discovered within postoperative 1 week and were cured by conservative treatment, while the other 1 case developed anastomotic fistula complicated with peritoneal infection who received laparoscopic exploration and peritoneal scavenge and drainage, then discharged 34 days later. Six patients in conventional group developed postoperative operation-associated complications, including 1 case of anastomotic bleeding, 3 cases of pancreatic leakage, 1 case of chyle leakage and 1 case of peritoneal infection. Morbidity of postoperative operation-associated complication was not significantly different between two groups [7.0%(7/100) vs. 11.5%(6/52), χ2=0.414, P=0.520]. Fifty patients from two groups underwent endoscopic examination at postoperative 6-month and 12-month, and no obvious anastomotic stenosis and esophageal reflux were observed. CONCLUSION: SPLT is a safe procedure with feasibibility in intracorporeal esophagojejunostomy.

Upregulation of circadian gene 'hClock' contribution to metastasis of colorectal cancer.

Recent studies have shown that disruption of the circadian rhythm was one of the endogenous factors contributing to tumorigenesis of various human malignancies, including colorectal cancer (CRC). However, the roles of circadian genes in the development of CRC are still unexplored. In this study, we investigated the expression pattern and the underlying mechanism of human Clock gene (hClock) in CRC progression. Multiple methods such as qRT-PCR, immunohistochemistry, and western blotting were performed to evaluate the expression pattern of the gene hClock, as well as to observe the changes of angiogenesis-related proteins and EMT-related proteins. Transwell cell migration assays and an animal tumor metastasis model were used to examine the impact of hClock on the metastatic ability of CRC cells in vitro and in vivo. Our results showed that the expression level of hClock significantly increased in human CRC tissues, which strongly associated with late TNM stage and positive lymph node metastasis. Moreover, a higher level of hClock expression was found in CRC cell lines with a higher metastatic potential. Furthermore, ectopic expression of hClock promoted the migration of SW480 CRC cells, while knockdown of hClock inhibited the tumor metastasis of SW620 CRC cells, and targeting hClock by shRNA effectively suppressed the metastatic ability of SW620 CRC cells in nude mice. Finally, we found that overexpression of hClock enhanced the expression of angiogenesis-related genes such as HIF-1α, ARNT and VEGF, and promoted epithelial-mesenchymal (-like) transition (EMT) in CRC cells, both of which are considered to be critical for tumor progression. These findings suggest that upregulation of the circadian gene hClock plays an important role in metastasis of colorectal cancer.

Circadian gene hCLOCK contributes to progression of colorectal carcinoma and is directly regulated by tumor­suppressive microRNA­124.

An abundance of studies has demonstrated that disruption of circadian rhythms is one of the factors that may contribute to the initiation and development of human colorectal carcinomas (CRCs). Recently, microRNA­124 has been demonstrated to suppress tumor growth or metastasis of CRCs. However, the mechanisms of cross­talk between microRNA­124 (miR­124) and circadian rhythms in the regulation of CRCs are poorly understood. The present study demonstrated that the protein expression levels of human circadian locomoter output cycles protein kaput (hCLOCK) is significantly increased, while miR­124 is attenuated in high­grade human CRC tissues and in the more invasive colorectal cancer cell lines SW620 and LOVO. It was further demonstrated that hCLOCK is a direct target of miR­124. Upregulation of miR­124 significantly inhibited hCLOCK expression in LOVO cells, and consequently inhibited its promoting effects on the proliferation and migration of LOVO cells. In conclusion, these data revealed that hCLOCK serves an enhancing role, whereas mir­124 serves a suppressive role, in human CRC. Attenuation of miR­124, of which hCLOCK is a direct target, leads to increased hCLOCK expression and disruption of circadian rhythms in CRC.