Downregulation of Circ-PITHD1 Suppressed Colorectal Cancer via Glycolysis Inhibition through miR-590-5p/HK2 Axis.

Colorectal cancer (CRC) is a frequent malignancy around the globe. Circular RNAs (circRNAs) are implicated in CRC development. Nevertheless, the regulatory mechanisms and biological functions regarding circRNAs in CRC progression are largely unclear. The present investigation employed next-generation sequencing (NGS) to study the abnormal circRNA expression in CRC tissues. The regulatory mechanism and targets were then analyzed by bioinformatics, luciferase reporter analysis, CCK8, colony formation, and Transwell migration. In vivo metastasis and tumorigenesis assays were conducted to elucidate circ-PITHD1 roles regarding CRC. The data showed that circ-PITHD1 expression increased in a CRC cell line and tissues, which indicated that circ-PITHD1 functioned in CRC progression. circ-PITHD1 downregulation inhibited CRC invasion and proliferation in the experiments. Luciferase reporter results confirmed that both miR-590-5p and hexokinase 2 (HK2) were circ-PITHD1 downstream targets. HK2 overexpression or miR-590-5p suppression reversed CRC cell proliferation and invasion after silencing of circ-PITHD1 by regulation of glycolysis. Taken together, this investigation discovered that circ-PITHD1 downregulation suppressed CRC progression by inhibiting glycolysis via the miR-590-5p/HK2 axis.

Study on the mechanism of LOXL1-AS1/miR-3614-5p/YY1 signal axis in the malignant phenotype regulation of hepatocellular carcinoma.

BACKGROUND: Hepatocellular carcinoma (HCC) is one of the most common malignant tumors with high mortality worldwide. Accumulating researches have indicated that long non­coding RNAs (lncRNAs) are involved in varies human cancers, including HCC. Nevertheless, the specific molecular mechanism of lncRNA lysyl oxidase like 1 antisense RNA 1 (LOXL1-AS1) in HCC is still unclear. METHODS: LOXL1-AS1 expression was tested via qRT-PCR in HCC cells. Functional and mechanism assays were respectively done to evaluate the biological functions of HCC cells and the potential interaction of LOXL1-AS1 and other factors. RESULTS: We discovered that LOXL1-AS1 was high expressed in HCC cells. Inhibition of LOXL1-AS1 repressed cell proliferation, migration and invasion, but enhanced cell apoptosis in HCC. Further, miR-3614-5p was proven to be sponged by LOXL1-AS1. Additionally, Yin Yang 1 (YY1) was proven as the target gene of miR-3614-5p, and YY1 depletion could repress HCC cell malignant behaviors. YY1 could also transcriptionally activate LOXL1-AS1 expression. In rescue assays, we confirmed that overexpression of YY1 or miR-3614-5p inhibition could reverse the suppressive effects of LOXL1-AS1 silence on the malignant behaviors of HCC cells. CONCLUSION: In short, LOXL1-AS1/miR-3614-5p/YY1 forms a positive loop in modulating HCC cell malignant behaviors.

Is Long Noncoding SNHG7 a Reliable Diagnostic Tool for Metastasis Diagnosis of Cancer: A Meta-Analysis.

Background: The small nucleolar RNA host gene 7 (SNHG7) has been suggested as a biomarker of metastatic cancer; however, its reliability is controversial. Therefore, the goal of this study was to conduct a meta-analysis to assess the reliability of SNHG7 as a comprehensive cancer metastasis diagnostic biomarker. Methods: A comprehensive literature search was conducted using PubMed, Cochrane Library, Web of Science, Embase, and China National Knowledge Infrastructure (CNKI) to identify articles which examined the role of SNHG7 in cancers. Random-effects models and fixed-effects models were conducted to estimate the pooled odds ratios (ORs) for the associations of SNHG7 with distant metastases and lymph node metastases. Hierarchical summary receiver operating characteristic (ROC) models were used to estimate the sensitivity and specificity of SNHG7 as a biomarker for cancer metastasis diagnoses. Results: Nineteen studies comprised 1491 patients were included in this meta-analysis. We found that both distant metastasis (OR = 4.19, 95% confidence interval [CI] = 2.93-5.99, I2 = 34%) and lymph node metastasis (OR = 3.07, 95% CI = 1.65-5.68, I2 = 79.03%) were significantly associated with a higher expression of SNHG7. We also showed a pooled sensitivity and specificity of 74% (95% CI = 66-82) and 57% (95% CI = 53-61) for distant metastasis; as well as 72% (95% CI = 63-80) and 54% (95% CI = 46-63) for lymph node metastasis, respectively. Conclusion: Our findings suggest that SNHG7 is a potential diagnostic biomarker for metastasis of cancer; however, its clinical application requires stronger evidence due to the low sensitivity and specificity. Further larger-scale studies from diverse settings and cancer types will be necessary to reveal novel insights into SNHG7 as a biomarker for cancer metastasis diagnoses.

A Comparison of Gastric and Jejunal Feeding in Hypercatabolism Associated With Hypothalamic AMPK-Autophagy-POMC in Endotoxemic Rats.

BACKGROUND: Hypercatabolism is associated with increased infectious rates and mortality in critically ill patients. Enteral nutrition (EN) is usually used to counteract hypercatabolism. However, the impact of different routes of EN on hypercatabolism remains unknown. Here, we compared the impact of gastric feeding (GF) and jejunal feeding (JF) on gastrointestinal hormones and hypercatabolism, which is associated with hypothalamic adenosine 5'-monophosphate-activated protein kinase (AMPK)-autophagy-proopiomelanocortin (POMC). METHODS: Sixty adult male Sprague-Dawley rats were divided into 5 groups: Sham and lipopolysaccharide (LPS) groups fed a standard chow diet, a pair-fed group that was a subset of saline-treated rats pair-fed with the LPS group, and LPS + JF and LPS + GF groups (received EN via jejunal and gastric tube, respectively, for 3 days [100 kcal/kg/d]). Hypercatabolism was measured by insulin resistance, muscle protein synthesis, and atrophy. Serum gastrointestinal hormones, hypothalamic ghrelin, growth hormone secretagogue receptor-1α (GHS-R1α), and AMPK-autophagy-POMC markers were also detected. RESULTS: GF increased serum total, acylated, desacylated, and hypothalamic ghrelin and decreased glucagon-like peptide-1 (GLP-1). But no effect on pancreatic polypeptide (PYY) and hypothalamic GHS-R1α was observed. JF showed no effect on hypothalamic ghrelin, GHS-R1α, and serum total, acylated, and desacylated ghrelin and even further aggravated GLP-1 and PYY. GF could effectively augment hypothalamic AMPK-autophagy-POMC and hypercatabolism. However, JF showed no effect on hypothalamic AMPK-autophagy-POMC and hypercatabolism. CONCLUSIONS: GF could activate hypothalamic AMPK-autophagy and suppress POMC expression via gastrointestinal hormones to ameliorate hypercatabolism compared with JF, which suggested that GF may be the preferred route of EN in endotoxemic rats.

Escin-induced DNA damage promotes escin-induced apoptosis in human colorectal cancer cells via p62 regulation of the ATM/γH2AX pathway.

Escin, a triterpene saponin isolated from horse chestnut seed, has been used to treat encephaledema, tissue swelling and chronic venous insufficiency. Recent studies show that escin induces cell cycle arrest, tumor proliferation inhibition and tumor cell apoptosis. But the relationship between escin-induced DNA damage and cell apoptosis in tumor cells remains unclear. In this study, we investigated whether and how escin-induced DNA damage contributed to escin-induced apoptosis in human colorectal cancer cells. Escin (5-80 µg/mL) dose-dependently inhibited the cell viability and colony formation in HCT116 and HCT8 cells. Escin treatment induced DNA damage, leading to p-ATM and γH2AX upregulation. Meanwhile, escin treatment increased the expression of p62, an adaptor protein, which played a crucial role in controlling cell survival and tumorigenesis, and had a protective effect against escin-induced DNA damage: knockdown of p62 apparently enhanced escin-induced DNA damage, whereas overexpression of p62 reduced escin-induced DNA damage. In addition, escin treatment induced concentration- and time-dependent apoptosis. Similarly, knockdown of p62 significantly increased escin-induced apoptosis in vitro and produced en escin-like antitumor effect in vivo. Overexpression of p62 decreased the rate of apoptosis. Further studies revealed that the functions of p62 in escin-induced DNA damage were associated with escin-induced apoptosis, and p62 knockdown combined with the ATM inhibitor KU55933 augmented escin-induced DNA damage and further increased escin-induced apoptosis. In conclusion, our results demonstrate that p62 regulates ATM/γH2AX pathway-mediated escin-induced DNA damage and apoptosis.

Size-Tunable Gd2O3@Albumin Nanoparticles Conjugating Chlorin e6 for Magnetic Resonance Imaging-Guided Photo-Induced Therapy.

Protein nanoparticles as nanocarriers are of particular interest in the field of cancer therapy. Nevertheless, so far a facile fabrication of theranostic protein nanoparticles have been explored with limited success for cancer imaging and therapy. In this work, we demonstrate the controllable synthesis of size-tunable Gd2O3@albumin conjugating photosensitizer (PS) (GA-NPs) using hollow albumin as the nanoreactor for magnetic resonance imaging (MRI)-guided photo-induced therapy. The growth of Gd2O3 nanocrystals within the hollow nanoreactors is well regulated through reaction time, and a typical PS (e.g. chlorin e6) is further conjugated with the protein corona of the nanoreactor through facile chemical coupling, followed by the formation of theranostic GA-NPs. GA-NPs exhibit good longitudinal relaxivity, ideal photostability, enhanced cellular uptakes, and preferable size-dependent tumor accumulation. Moreover, GA-NPs effectively generate remarkable photothermal effect, intracellular reactive oxygen species from Ce6, and subsequent cytoplasmic drug translocation, thereby leading to severe synergistic photothermal and photodynamic cell damages. Consequently, GA-NPs exhibit an in vivo size-dependent MRI capacity with enhanced imaging contrast for effective tumor localization, and also generate a potent synergistic photodynamic therapy/photothermal therapy efficacy under irradiation owing to their enhanced tumor accumulation and strong photo-induced cytotoxicity. These results suggest that GA-NPs can act as a promising theranostic protein nanoplatform for cancer imaging and photo-induced therapy.

Anti-metastatic activity of fangchinoline in human gastric cancer AGS cells.

Fangchinoline (FCL) is an active component isolated from the traditional medicinal plant Stephania tetrandra S. Moore, and has been reported to possess anti-cancer functions in several types of cancers; however, the effect of FCL on gastric cancer metastasis and its underlying molecular mechanisms remain unknown. The current study aimed to investigate the effect of FCL on the cell migration and invasion of human metastatic gastric cancer AGS cells and its mechanisms. Our study demonstrates that FCL dosage dependently suppressed the adhesion, migration and invasion capacities of human gastric cancer AGS cells without obvious cytotoxic effects. Reverse transcription-polymerase chain reaction and western blot assays demonstrated that FCL greatly inhibited the expression of matrix metalloproteinase (MMP)-2 and MMP-9 at both the mRNA and protein levels, while it significantly increased the expression of tissue inhibitor of metalloproteinase (TIMP) 1 and TIMP2 messenger RNAs. Our results also indicated that FCL repressed the phosphorylation of AKT in gastric cancer AGS cells. In summary, FCL may exert its anti-metastatic property in human gastric cancer cells in vitro by suppression of MMP-2 and MMP-9, increase of TIMP1 and TIMP2 genes, and inhibition of AKT phosphorylation. FCL may be a drug candidate for the treatment of gastric cancer metastasis.

Preclinical study of cinobufagin as a promising anti-colorectal cancer agent.

Here, we assessed the anti-colorectal cancer (CRC) cell activity of cinobufagin (CBG). We found that CBG exerted potent cytotoxic and anti-proliferative activity against CRC lines (HCT-116 and HT-29) and primary human CRC cells. Meanwhile, it activated apoptosis, and disrupted cell-cycle progression in the cells. At the signaling level, CBG treatment in CRC cells provoked endoplasmic reticulum stress (ER stress), the latter was evidenced by caspase-12 activation, CHOP expression, as well as PERK and IRE1 phosphorylations. Contrarily, the ER stress inhibitor salubrinal, the caspase-12 inhibitor and CHOP shRNA remarkably attenuated CBG-induced CRC cell death and apoptosis. Further, CBG in-activated mammalian target or rapamycin complex 1 (mTORC1), which appeared responsible for proliferation inhibition in CRC cells. Introduction of a constitutively-active S6K1 ("ca-S6K1") restored proliferation of CBG-treated CRC cells. Finally, CBG intraperitoneal injection suppressed HCT-116 xenograft tumor growth in the nude mice. CHOP upregulation and mTORC1 in-activation were also noticed in CBG-treated HCT-116 tumors. The results of this preclinical study suggest that CBG could be tested as promising anti-CRC agent.