Identification of necroptosis-related lncRNAs for prognosis prediction and screening of potential drugs in patients with colorectal cancer.

BACKGROUND: Tumor recurrence and metastasis lead to a poor prognosis in colorectal cancer (CRC). Necroptosis is closely related to the tumor microenvironment (TME) and affects tumor recurrence and metastasis. We aimed to stratify CRC patients according to necroptosis-related long noncoding RNAs (lncRNAs), which can be used to not only evaluate prognosis and improve precision medicine in clinical practice but also screen potential immunotherapy drugs. AIM: To stratify CRC patients according to necroptosis-related lncRNAs (NRLs), which can be used to not only evaluate prognosis and improve precision medicine in clinical practice but also screen potential immunotherapy drugs. METHODS: LncRNA expression profiles were collected from The Cancer Genome Atlas. NRLs were identified by coexpression analysis. Cox regression analysis identified a NRL signature. Then, the value of this signature was comprehensively and multidimensionally evaluated, and its reliability for CRC prognosis prediction was assessed with clinical CRC data and compared with that of six other lncRNA signatures. Gene set enrichment analysis, TME analysis and half-maximal inhibitory concentration (IC50) prediction were also performed according to the risk score (RS) of the signature. RESULTS: An 8-lncRNA signature significantly associated with overall survival (OS) was constructed, and its reliability was validated with clinical CRC data. Most of the areas under the receiver operating characteristic curves (AUCs) values for 1-, 3- and 5-year OS for this signature were higher than those for the other six lncRNA signatures. OS, disease-specific survival and the progression-free interval were all significantly poorer in the high-risk group. The RS of the signature showed good concordance with the predicted prognosis, with AUCs for 1-, 3- and 5-year OS of 0.79, 0.81 and 0.77, respectively. Additionally, the calibration plots for this signature combined with clinical factors showed that this combination could effectively improve the ability to predict OS. The RS was correlated with tumor stage, lymph node metastasis and distant metastasis. Most of the enriched Kyoto Encyclopedia of Genes and Genomes and Gene Ontology terms were tumor metastasis-related pathways in the high-risk group; these patients showed greater infiltration of immunosuppressive cells, such as cancer-associated fibroblasts, hematopoietic stem cells and M2 macrophages, but less infiltration of infiltrating antitumor effector immune cells, such as cluster of differentiation 8+ T cells and regulatory T cells (Tregs). We explored additional potential immune checkpoint genes and potential immunotherapeutic and chemotherapeutic drugs with relatively low IC50 values. CONCLUSION: We identified an NRL signature with strong fidelity that could stably predict prognosis and might be an indicator of the TME of CRC. Furthermore, additional potential immunotherapeutic and chemotherapeutic drugs were explored.

MiR-216b inhibits gastric cancer proliferation and migration by targeting PARK7.

OBJECTIVE: Postoperative recurrence and metastasis of gastric cancer is still a difficult problem in medical field. About 60% of patients with advanced gastric cancer die from peritoneal metastasis, which has become one of the main causes of death of gastric cancer patients. To elucidate the molecular mechanism of peritoneal metastasis of gastric cancer can help us better early diagnosis and improve treatment measures. METHODS: This project intends to validate the above hypothesis from three different levels of tissue, cell, and animal models by means of fluorescence quantitative PCR, Western blot, double Luciferase Report Analysis and immunohistochemical detection, and to further explore the molecular mechanism of peritoneal metastasis of gastric cancer. RESULTS: Our previous studies have shown that PARK7 promotes peritoneal metastasis of gastric cancer through PI3K/Akt signaling pathway, but its specific regulatory mechanism remains unclear. CONCLUSION: Our preliminary study showed that the expression of microRNA-216b in gastric cancer tissues with peritoneal metastasis was significantly lower than that in patients without peritoneal metastasis, while the expression of PARK7 was the opposite.

Meta-analysis of natural orifice specimen extraction versus conventional laparoscopy for colorectal cancer.

OBJECTIVE: To compare natural orifice specimen extraction surgery (NOSES) and conventional laparoscopic (LAP) surgery in treating colorectal cancer. METHODS: The present authors conducted a systematic search in the PubMed, EMBASE, and Cochrane databases for randomized controlled trials (RCTs), prospective nonrandomized studies, and retrospective studies up to May 2019. We used postoperative complications as the main endpoints, and used hospital stay, time to first flatus, operative time, postoperative pain, cosmetic result, wound infections, and oncological outcomes as the secondary endpoints. Subgroup analyses were conducted according to the different specimen extraction sites (transanal and transvaginal). A sensitivity analysis was carried out to evaluate the reliability of the outcomes. RevMan5.3 software was used for statistical analysis. RESULT: Twelve studies (one RCT, ten retrospective studies, and one prospective nonrandomized study) involving a total of 1437 patients (NOSES group 665 patients and LAP surgery group 772 patients) were included. Meta-analysis showed that compared with LAP surgery, NOSES resulted in a shorter hospital stay (WMD = -0.79 days; 95% CI -1.17 to -0.42; P < 0.001; P = 0.02), a shorter time to first flatus (WMD = -0.58 days; 95% CI -0.75 to -0.40; P < 0.001), less postoperative pain (WMD = -1.51; 95% CI -1.99 to -1.04; P < 0.001), a better cosmetic result (WMD = 1.37; 95% CI 0.59 to 2.14; P < 0.001), and fewer wound infections (OR = 0.13; 95% CI 0.05 to 0.35; P < 0.001) and postoperative complications (OR = 0.48; 95% CI 0.36 to 0.65; P < 0.001). Oncological outcomes did not differ between the two groups, while the operative time (WMD = 13.95 min; 95% CI 4.55 to 23.35; P = 0.004) was longer in the NOSES group. CONCLUSION: The present systematic meta-analysis is an attempt to assess the impact of NOSES, namely, its oncological outcomes and surgical safety in colorectal cancer patients. Pooled comparisons revealed that NOSES was superior to LAP surgery in terms of postoperative morbidity, postoperative pain, hospital stay, the time to first flatus, cosmetic results, and wound infections; however, NOSES was associated with a longer operative time. Considering the abovementioned limitations and the very low level of evidence of the comparisons, further RCTs are required to verify the results of our study.

Identification of key candidate genes for colorectal cancer by bioinformatics analysis.

Colorectal cancer (CRC) is one of the most common cancers of the digestive tract. Although numerous studies have been conducted to elucidate the cause of CRC, the exact mechanism of CRC development remains to be determined. To identify candidate genes that may be involved in CRC development and progression, the microarray datasets GSE41657, GSE77953 and GSE113513 were downloaded from the Gene Expression Omnibus database. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes were used for functional enrichment analysis of differentially expressed genes (DEGs). A protein-protein interaction network was constructed, and the hub genes were subjected to module analysis and identification using Search Tool for the Retrieval of Interacting Genes/Proteins and Cytoscape. A total of 142 DEGs were identified, with enriched functions and pathways in the 'cell cycle', 'cell proliferation', 'the mitotic cell cycle' and 'one-carbon metabolic process'. In addition, 10 hub genes were identified, and functional analysis indicated that these genes are mainly enriched in 'cell division', 'cell cycle' and functions associated with nucleotide binding processes. Survival analysis demonstrated that DNA topoisomerase II α, cyclin-dependent kinase 1 and CDC28 protein kinase regulatory subunit 2 may be involved in cancer invasion or recurrence. The DEGs identified in the present study may help explain the molecular mechanisms of CRC development and progression.

The Effects of Pre-Operative Enteral Nutrition from Nasal Feeding Tubes on Gastric Outlet Obstruction.

We examined gastric outlet obstruction (GOO) patients who received two weeks of strengthening pre-operative enteral nutrition therapy (pre-EN) through a nasal-jejenal feeding tube placed under a gastroscope to evaluate the feasibility and potential benefit of pre-EN compared to parenteral nutrition (PN). In this study, 68 patients confirmed to have GOO with upper-gastrointestinal contrast and who accepted the operation were randomized into an EN group and a PN group. The differences in nutritional status, immune function, post-operative complications, weight of patients, first bowel sound and first flatus time, pull tube time, length of hospital stay (LOH), and cost of hospitalization between pre-operation and post-operation were all recorded. Statistical analyses were performed using the chi square test and t-test; statistical significance was defined as p < 0.05. The success rate of the placement was 91.18% (three out of 31 cases). After pre-EN, the levels of weight, albumin (ALB), prealbumin (PA), and transferrin (TNF) in the EN group were significantly increased by pre-operation day compared to admission day, but were not significantly increased in the PN group; the weights in the EN group were significantly increased compared to the PN group by pre-operation day and day of discharge; total protein (TP), ALB, PA, and TNF of the EN group were significantly increased compared to the PN group on pre-operation and post-operative days one and three. The levels of CD3+, CD4+/CD8+, IgA, and IgM in the EN group were higher than those of the PN group at pre-operation and post-operation; the EN group had a significantly lower incidence of poor wound healing, peritoneal cavity infection, pneumonia, and a shorter first bowel sound time, first flatus time, and post-operation hospital stay than the PN group. Pre-EN through a nasal-jejunum feeding tube and placed under a gastroscope in GOO patients was safe, feasible, and beneficial to the nutrition status, immune function, and gastrointestinal function, and sped up recovery, while not increasing the cost of hospitalization.

Mitogen-activated protein kinase-activated protein kinase 2 is a critical regulator of pig oocyte meiotic maturation.

Mitogen-activated protein kinase (MAPK)-activated protein kinase 2 (MK2), a direct substrate of p38 MAPK, plays key roles in multiple cellular processes. In the present study, we showed that MK2 affected not only cumulus expansion, but also the oocyte meiotic cell cycle in porcine oocytes. Inhibition of MK2 arrested oocytes at the germinal vesicle (GV) stage or the prometaphase I/metaphase I stage. Unlike in mouse oocytes, where phosphorylated (p-) MK2 was localised at the minus end of spindle microtubules and close to the spindle poles, in porcine oocytes p-MK2 was concentrated at the spindle equator and localised at the plus end of spindle microtubules. Knockdown or inhibition of MK2 resulted in spindle defects: spindles were surrounded by irregular chromosome non-disjunction or by chromosomes detached from the spindles. MK2 regulated spindle organisation and chromosome alignment by connecting microtubules with kinetochores. In addition, unlike in mitotic cells and meiotic mouse oocytes, the MK2-p38 MAPK pathway may not play an important role during meiotic cell cycle in porcine oocytes. In conclusion, MK2 is an important regulator of porcine oocyte meiotic maturation.

KISS1 methylation and expression as predictors of disease progression in colorectal cancer patients.

AIM: To examine the effect of aberrant methylation of the KISS1 promoter on the development of colorectal cancer (CRC) and to investigate reversing aberrant methylation of the KISS1 promoter as a potential therapeutic target. METHODS: KISS1 promoter methylation, mRNA expression and protein expression were detected by methylation-specific polymerase chain reaction (PCR), real-time quantitative PCR and Western blotting, respectively, in 126 CRC tissues and 142 normal colorectal tissues. Human CRC cells with KISS1 promoter hypermethylation and poor KISS1 expression were treated in vitro with 5-aza-2'-deoxycytidine (5-Aza-CdR). After treatment, KISS1 promoter methylation, KISS1 mRNA and protein expression and cell migration and invasion were evaluated. RESULTS: Hypermethylation of KISS1 occurred frequently in CRC samples (83.1%, 105/126), but was infrequent in normal colorectal tissues (6.34%, 9/142). Moreover, KISS1 methylation was associated with tumor differentiation, the depth of invasion, lymph node metastasis and distant metastasis (P < 0.001). KISS1 methylation was also associated with low KISS1 expression (P < 0.001). Furthermore, we observed re-expression of the KISS1 gene and decreased cell migration after 5-Aza-CdR treatment in a CRC cell line. CONCLUSION: These data suggest that KISS1 is down-regulated in cancer tissues via promoter hypermethylation and therefore may represent a candidate target for treating metastatic CRC.

[Kiss-1 gene expression after radiation and its association with proliferation and apoptosis in colorectal cancer cells].

OBJECTIVE: To investigate the change of expression level of metastasis suppressor gene Kiss-1 in the colorectal cancer cell line SW480 after radiation, and to determine its association with the proliferation and apoptosis of SW480 cells. METHODS: SW480 cells were divided into control group (0 Gy) and study groups (2, 4, 6, 8 Gy). Cells in the study groups were irradiated by 6-MV X-ray radiation for 48 hours. Immunohistochemistry and real-time PCR methods were used to investigate the influence of radiation on Kiss-1 gene expression of SW480. Colony formation assay was used to detect the proliferation of SW480. Flow cytometry-Annexin- V/PI assay was used to observe the change of the apoptosis rate. RESULTS: Compared with the control group, Kiss-1 protein expression increased after radiation of 6, 8 Gy (P<0.05), but no significant changes were observed after radiation of 2, 4 Gy(P>0.05). Kiss-1 gene mRNA level increased after radiation of 2, 4, 6 Gy, while no obvious change was observed for 8 Gy radiation. The apoptosis rates increased for 4, 6, 8 Gy radiation(P<0.05), however, there was no significant difference for 2 Gy radiation (P<0.05). CONCLUSION: Radiation may increase Kiss-1 gene expression in SW480 cells, which results in decreases proliferation and increases apoptosis in residual surviving cells.

[Influencing factors related to lymphatic metastasis of T2 rectal carcinoma].

OBJECTIVE: To study the risk factors associated with lymphatic metastasis of T2 rectal carcinoma. METHODS: A consecutive series of 122 patients with T2 rectal cancer who underwent radical surgery in the First Affiliated Hospital of Fujian Medical University from 2006 to 2011 were included for retrospective analysis. Risk factors associated with lymphatic metastasis were investigated. RESULTS: The rate of lymph node metastasis was 21.3% (26/122). Distance to anal verge(P<0.05), morphological type(P<0.05), histological type(P<0.05), tumor differentiation(P<0.05), and depth of invasion(P<0.05) were risk factors for lymph node metastasis in T2 rectal cancer by univariate analysis. The depth of invasion remained statistically significant by multivariate analysis. The rate of lymph node metastasis was 13%(7/54) in patients with shallow muscularis propria involvement, and 28%(19/68) in those with deep muscularis involvement. CONCLUSION: For T2 rectal cancer with shallow muscularis involvement, the risk of lymph node metastasis is low and transanal excision should be considered.

Clinical analysis of solid-pseudopapillary tumor of the pancreas: report of 15 cases.

BACKGROUND: Solid-pseudopapillary tumor of the pancreas (SPTP) is an uncommon and enigmatic pancreatic neoplasm that occurs mainly in young women. Although more and more cases have been reported in recent years, misdiagnosis and incorrect treatment still frequently take place. This study was designed to stimulate consideration of this tumor. METHODS: We retrospectively reviewed the experience of diagnosis and treatment of 15 patients with SPTP and compared them with 516 patients with pancreatic cancer from January 1997 to March 2007. RESULTS: Most of the SPTP cases were asymptomatic except for one palpable mass. Almost all SPTPs demonstrated a solid structure with hypo- or iso-attenuation, cystic structure with hypo-attenuation on pre-contrast CT scan, and enhancement of solid portions on post-contrast CT scan. By contrast, most cases of pancreatic carcinoma had multiple symptoms and abnormal blood results. The tumors showed hypo-attenuation on both pre-contrast and post-contrast CT scan, and only a few showed iso-attenuation on post-contrast CT scan. All cases of SPTP in our group were cured by surgical resection, while only 16.86% of patients with pancreatic carcinoma could undergo a radical resection. CONCLUSIONS: Clinical features and CT scans were helpful to differentiate SPTP from pancreatic carcinoma. Radical surgical resection was the most effective and safe method for the treatment of SPTP.