[Laparoscopic reoperation for recurred antireflux surgery of gastroesophageal reflux disease]

OBJECTIVE

To investigate the safety and effectiveness of laparoscopic reoperation for patients with gastroesophageal reflux disease (GERD) recurred form previous anti-reflux surgery.

METHODS

Totally 19 patients received laparoscopic reoperation for symptomatic and anatomic recurred GERD in Department of Gastroesophageal Reflux Disease, Rocket Force General Hospital from January 2008 to September 2015 were retrospectively analyzed. There were 12 male and 7 female patients. The average reoperation age was (48±14) years, the average duration of reoperation from original ones was (43±38) months. The patients underwent preoperative barium, endoscopy, manometry and 24-hour pH studies. Laparoscopic hiatal hernia repair plus fundoplication was carried out for reoperation. Gastroesophageal reflux related symptoms (reflux, heartburn, chest pain, chough, wheezing, chest tightness and globus sensation) before and after surgery were compared by a questionnaire. The patients' medication consumption, complications and satisfaction of the reoperation were investigated as well. The repeated measures analysis of variance was used for statistical comparison of data preoperatively and postoperatively.

RESULTS

No major complication and death occurred. Six cases (32%) had complications such as diarrhea, increased passing wind, flatulence, dysphagia and abdominal pain. The GERD related symptom score of reflux, heartburn, chest pain, chough, wheezing, chest tightness and globus sensation all significantly decreased (F: 25.0 to 56.7; P: 0.000 to 0.001) after the reoperation, with 68% good outcome of all the patients. After a follow-up of (33±22) months after reoperation, 1 case had partial recurrence at the 3(rd) month after reoperation. For all the patients, 12 cases felt very satisfied or satisfied with the reoperation.

CONCLUSION

Laparoscopic reoperation is generally effective with acceptable morbidity rates for patients with esophageal and extraesophageal symptoms recurred form previous hiatal repair and (or) fundoplication.

Increased glycogen synthase kinase-3β and hexose-6-phosphate dehydrogenase expression in adipose tissue may contribute to glucocorticoid-induced mouse visceral adiposity

BACKGROUND

Increased adiposity in visceral depots is a crucial feature associated with glucocorticoid (GC) excess. The action of GCs in target tissue is regulated by GC receptor (GR) and 11ß-hydroxysteroid dehydrogenase type 1 (11ß-HSD1) coupled with hexose-6-phosphate dehydrogenase (H6pdh). Glycogen synthase kinase-3β (GSK3β) is known to be a crucial mediator of ligand-dependent gene transcription. We hypothesized that the major effects of corticosteroids on adipose fat accumulation are in part medicated by changes in GSK3β and H6pdh.

METHODS

We characterized the alterations of GSK3β and GC metabolic enzymes, and determined the impact of GR antagonist mifepristone on obesity-related genes and the expression of H6pdh and 11ß-HSD1 in adipose tissue of mice exposed to excess GC as well as in in vitro studies using 3T3-L1 adipocytes treated with GCs.

RESULTS

Corticosterone (CORT) exposure increased abdominal fat mass and induced expression of lipid synthase ACC and ACL with activation of GSK3β phosphorylation in abdominal adipose tissue of C57BL/6J mice. Increased pSer⁹ GSK3β was correlated with induction of H6pdh and 11ß-HSD1. Additionally, mifepristone treatment reversed the production of H6pdh and attenuated CORT-mediated production of 11ß-HSD1 and lipogenic gene expression with reduction of pSer⁹ GSK3β, thereby leading to improvement of phenotype of adiposity within adipose tissue in mice treated with excess GCs. Suppression of pSer⁹ GSK3β by mifepristone was accompanied by activation of pThr³⁰⁸ Akt and blockade of CORT-induced adipogenic transcriptor C/EBPα and PPARγ. In addition, mifepristone also attenuated CORT-mediated activation of IRE1α/XBP1. Additionally, reduction of H6pdh by shRNA showed comparable effects to mifepristone on attenuating CORT-induced expression of GC metabolic enzymes and improved lipid accumulation in vitro in 3T3-L1 adipocytes.

CONCLUSION

These findings suggest that elevated adipose GSK3β and H6pdh expression contribute to 11ß-HSD1 mediating hypercortisolism associated with visceral adiposity.

Artesunate protects pancreatic beta cells against cytokine-induced damage via SIRT1 inhibiting NF-κB activation

AIM

Artesunate (ART) has been known as the most effective and safe reagents to treat malaria for many years. In this study, we explored whether ART could protect pancreatic beta-cell against cytokine-induced damage.

MATERIALS AND METHODS

The production of nitrite (NO) was detected with the Griess Assay Kit. SIRT1 and inducible nitric oxide synthase (iNOS) expression were determined with Western blot. The transcriptional activity of NF-κB was evaluated by luciferase reporter assay. The expression of Sirt1 was silenced by RNA interference. Glucose-stimulated insulin secretion (GSIS) and potassium-stimulated insulin secretion (KSIS) assays were performed to measure the effect of ART on pancreatic beta-cells' function. The effect of ART on beta-cells apoptosis was evaluated by using Hochest/PI staining and TUNEL assay.

RESULTS

ART enhanced GSIS (KSIS) and reduced apoptosis of pancreatic beta-cells induced by IL-1β. Further study showed that ART inhibited IL-1β-induced increase of NF-κB activity, iNOS expression, and NO production. Moreover, ART up-regulated SIRT1 expression in INS-1 cells and islets exposed to IL-1β. Inhibition of SIRT1 expression could partially abolished the inhibitory effect of ART on NF-κB activity in IL-1β-treated beta-cells. More importantly, the protective effect of ART on cytokine-induced damage was reversed by silencing SIRT1 expression.

CONCLUSIONS

ART can elicit a protective effect on beta-cells exposed to IL-1β by stimulating SIRT1 expression, which resulted in the decrease of NF-κB activity, iNOS expression, and NO production. Hence, ART might be an effective drug for diabetes.

Loss of ATF3 promotes hormone-induced prostate carcinogenesis and the emergence of CK5(+)CK8(+) epithelial cells

Steroid sex hormones can induce prostate carcinogenesis, and are thought to contribute to the development of prostate cancer during aging. However, the mechanism for hormone-induced prostate carcinogenesis remains elusive. Here we report that activating transcription factor 3 (ATF3) – a broad stress sensor – suppressed hormone-induced prostate carcinogenesis in mice. While implantation of testosterone and estradiol (T+E₂) pellets for 2 months in wild-type mice rarely induced prostatic intraepithelial neoplasia (PIN) in dorsal prostates (1 out of 8 mice), loss of ATF3 led to the appearance of not only PIN but also invasive lesions in almost all examined animals. The enhanced carcinogenic effects of hormones on ATF3-deficient prostates did not appear to be caused by a change in estrogen signaling, but were more likely a consequence of elevated androgen signaling that stimulated differentiation of prostatic basal cells into transformation-preferable luminal cells. Indeed, we found that hormone-induced lesions in ATF3-knockout mice often contained cells with both basal and luminal characteristics, such as p63⁺ cells (a basal cell marker) showing luminal-like morphology, or cells double-stained with basal (CK5⁺) and luminal (CK8⁺) markers. Consistent with these findings, low ATF3 expression was found to be a poor prognostic marker for prostate cancer in a cohort of 245 patients. Our results thus support that ATF3 is a tumor suppressor in prostate cancer.

RNF126 promotes homologous recombination via regulation of E2F1-mediated BRCA1 expression

RNF126 is an E3 ubiquitin ligase. The deletion of RNF126 gene was observed in a wide range of human cancers and is correlated with improved disease-free and overall survival. These data highlights the clinical relevance of RNF126 in tumorigenesis and cancer therapy. However, the specific functions of RNF126 remain largely unknown. Homologous recombination (HR)-mediated DNA double-strand break repair is important for tumor suppression and cancer therapy resistance. Here, we demonstrate that RNF126 facilitates HR by promoting the expression of BRCA1, in a manner independent of its E3 ligase activity but depending on E2F1, a well-known transcription factor of BRCA1 promoter. In support of this result, RNF126 promotes transactivation of BRCA1 promoter by directly binding to E2F1. Most importantly, an RNF126 mutant lacking 11 amino acids that is responsible for the interaction with E2F1 has a dominant-negative effect on BRCA1 expression and HR by suppressing E2F1-mediated transactivation of BRCA1 promoter and blocking the enrichment of E2F1 on BRCA1 promoter. Lastly, RNF126 depletion leads to the increased sensitivity to ionizing radiation (IR) and poly (ADP-ribose) polymerase (PARP) inhibition. Collectively, our results suggest a novel role of RNF126 in promoting HR-mediated repair through positive regulation on BRCA1 expression by direct interaction with E2F1. This study not only offers novel insights into our current understanding of the biological functions of RNF126 but also provides a potential therapeutic target for cancer treatment.

International Mycoplasma pneumoniae typing study: interpretation of M. pneumoniae multilocus variable-number tandem-repeat analysis

Typing of Mycoplasma pneumoniae by multiple-locus variable-number tandem repeat analysis (MLVA) is increasingly in use. However, no specific internationally agreed guidance is available. Thirty M. pneumoniae DNA samples including serial dilutions of a type strain were sent to six international laboratories to perform MLVA and results were compared. Good correlation was observed, indicating that this methodology can be robustly performed in multiple sites. However, differences due to interpretation of fragment size, repeat sequence identification and repeat numbering led to inconsistency in the final profiles assigned by laboratories. We propose guidelines for interpreting M. pneumoniae MLVA typing and assigning the number of repeats.

Dysregulated choline metabolism in T-cell lymphoma: role of choline kinase-α and therapeutic targeting

Cancer cells have distinct metabolomic profile. Metabolic enzymes regulate key oncogenic signaling pathways and have an essential role on tumor progression. Here, serum metabolomic analysis was performed in 45 patients with T-cell lymphoma (TCL) and 50 healthy volunteers. The results showed that dysregulation of choline metabolism occurred in TCL and was related to tumor cell overexpression of choline kinase-α (Chokα). In T-lymphoma cells, pharmacological and molecular silencing of Chokα significantly decreased Ras-GTP activity, AKT and ERK phosphorylation and MYC oncoprotein expression, leading to restoration of choline metabolites and induction of tumor cell apoptosis/necropotosis. In a T-lymphoma xenograft murine model, Chokα inhibitor CK37 remarkably retarded tumor growth, suppressed Ras-AKT/ERK signaling, increased lysophosphatidylcholine levels and induced in situ cell apoptosis/necropotosis. Collectively, as a regulatory gene of aberrant choline metabolism, Chokα possessed oncogenic activity and could be a potential therapeutic target in TCL, as well as other hematological malignancies with interrupted Ras signaling pathways.

Loss of ATF3 promotes Akt activation and prostate cancer development in a Pten knockout mouse model

Activating transcription factor 3 (ATF3) responds to diverse cellular stresses, and regulates oncogenic activities (for example, proliferation, survival and migration) through direct transcriptional regulation or protein-protein interactions. Although aberrant ATF3 expression is frequently found in human cancers, the role of ATF3 in tumorigenesis is poorly understood. Here, we demonstrate that ATF3 suppresses the development of prostate cancer induced by knockout of the tumor suppressor Pten in mouse prostates. Whereas the oncogenic stress elicited by Pten loss induced ATF3 expression in prostate epithelium, we found that ATF3 deficiency increased cell proliferation and promoted cell survival, leading to early onset of mouse prostatic intraepithelial neoplasia and the progression of prostate lesions to invasive adenocarcinoma. Importantly, the loss of ATF3 promoted activation of the oncogenic AKT signaling evidenced by high levels of phosphorylated AKT and S6 proteins in ATF3-null prostate lesions. In line with these in vivo results, knockdown of ATF3 expression in human prostate cancer cells by single guided RNA-mediated targeting activated AKT and increased matrix metalloproteinase-9 expression. Our results thus link ATF3 to the AKT signaling, and suggest that ATF3 is a tumor suppressor for the major subset of prostate cancers harboring dysfunctional Pten.

First Report of Barley yellow striate mosaic virus on Wheat in China

In the spring of 2014, a survey of viral diseases on wheat (Triticum aestivum L.) was carried out in Hebei Province, China. The samples with virus-like symptoms of dwarfing and flag leaf yellowing were collected in Zhaoxian, Quyang, Anxin, and Luannan. To reproduce the viral symptoms and confirm whether the unknown virus was transmitted by insect vectors, the nymphs of aviruliferous planthopper (Laodelphax striatellus Fallen, Homoptera: Delphacidae) were transferred onto diseased wheat from the field for a 3-day acquisition access period and a 10-day incubation on fresh wheat seedlings, and then were exposed to 2- to 3-leaf stage wheat seedlings of wheat variety Shixin828 for a 3-day inoculation access period. The infected wheat plants developed mosaic symptoms on the young leaves at 7 days post inoculation (dpi), and followed with severe symptoms including stunting, chlorotic spots, and striation along the veins of leaves at around 14 dpi. The infection symptoms were same as in the field but distinct from wheat infected with Rice black streaked dwarf virus (RBSDV) or Northern cereal mosaic virus (NCMV). For further confirmation, total RNA was extracted from the symptomatic wheat leaves, and NCMV specific primers, NCMV-PF/NCMV-PR (5'-ATGGATAAGAAAGCAAGTGGA-3'/5'-TTAAAAGTCGGCATACGGGTC-3') and RBSDV specific primers, S10-F/S10-R (5'-TTACCCAACATCACGCAACT-3'/5'-GAGCAGGAACTTCACGACAAC-3') were used for amplification of sequences of phosphoprotein and coat protein genes, respectively. Neither RBSDV nor NCMV were present in the symptomatic tissue according to the RT-PCR assay (4). Tissues derived from symptomatic wheat leaves were fixed and embedded in Spurr's resin and used for ultra-thin sectioning and transmission electron microscopy observations, revealing large amounts of Rhabdovirus-like particles in the cytoplasm. The identified particles were about 315 to 353 × 46 to 57 nm, similar in size to Barley yellow striate mosaic virus (BYSMV), a member of the genus Cytorhabdovirus reported from Italy (2). The specific primer pair (5'-ACTAAGGGGGTACTCCGACC-3' and 5'-CTGATCTGCTTTGAGGGGCA-3') was designed based on the reported polymerase (L) gene sequence of BYSMV isolate Zanjan-1 (GenBank Accession No. FJ665628) (1), and used for the BYSMV detection by RT-PCR. A single bright band of the expected size (~500 bp) was obtained from total RNA extracted from the plants exhibiting symptoms in the greenhouse. No such band was amplified from asymptomatic plants, while 15 out of 23 field samples also produced the same 500-bp products in RT-PCR. PCR products from three virus-positive field samples were sequenced directly and the sequences were submitted to GenBank (KM052176, KM052177, and KM052178). BLAST search showed that the sequences shared 96 to 97% nucleotide identity with the polymerase L gene sequence of BYSMV isolate Zanjan-1, whereas only 73 to 75% identity with NCMV (AB030277 and GU985153) (1,3,5). To our knowledge, this is the first report of BYSMV occurrence on wheat in China. References: (1) R. Almasi et al. J. Phytopathol. 158:351, 2010. (2) A. Appiano et al. Cytol. 6:105, 1974. (3) H. C. Chen et al. Sci. Agric. Sinica 3:64, 1980. (4) X. F. Duan et al. Acta Phytopathol. Sinica 40:337, 2010. (5) F. Tanno et al. Arch. Virol. 145:1373, 2000.

Epidemiological characteristics of motor neuron disease in Chinese patients

BACKGROUND

The epidemiology, diagnosis, and treatment of motor neuron disease (MND) in Chinese patients are ill known.

METHODS

A registered study of 461 MND patients was conducted across 10 facilities in 7 Chinese cities from February 2009 to March 2010.

RESULTS

Patients were classified as amyotrophic lateral sclerosis (ALS) (84.4%), progressive bulbar palsy (PBP) (4.1%), progressive muscular atrophy (PMA) (10.4%), or primary lateral sclerosis (PLS) (0.9%). MND was predominant in men (men/women; 1.6:1.0). Mean onset age was 52.6 years, with the highest incidence being observed between 51 and 60 years. Notably, 26.0% of MND patients were employed in forestry, fishery, or animal husbandry industries. Ten cases (2.7%) reported family history of MND, and 54.2% exhibited cervical onset. MND was also associated with head/neck trauma. Non-invasive positive pressure ventilation was the most common supportive therapy.

CONCLUSION

As a novel comprehensive report of a Chinese population, this study reveals that epidemiological characteristics of MND patients were similar to those observed in international populations. MND is age-related, male gender predominant, and may be associated with both environmental and genetic risk factors.

Activation of mTOR pathway in myeloid-derived suppressor cells stimulates cancer cell proliferation and metastasis in lal(-/-) mice

Inflammation critically contributes to cancer metastasis, in which myeloid-derived suppressor cells (MDSCs) are an important participant. Although MDSCs are known to suppress immune surveillance, their roles in directly stimulating cancer cell proliferation and metastasis currently remain unclear. Lysosomal acid lipase (LAL) deficiency causes systemic expansion and infiltration of MDSCs in multiple organs and subsequent inflammation. In the LAL-deficient (lal^−/−) mouse model, melanoma metastasized massively in allogeneic lal^−/− mice, which was suppressed in allogeneic lal^+/+ mice due to immune rejection. Here we report for the first time that MDSCs from lal^−/− mice directly stimulated B16 melanoma cell in vitro proliferation, and in vivo growth and metastasis. Cytokines i.e., IL-1β and TNFα from MDSCs are required for B16 melanoma cell proliferation in vitro. Myeloid-specific expression of human LAL (hLAL) in lal^−/− mice rescues these malignant phenotypes in vitro and in vivo. The tumor-promoting function of lal^−/− MDSCs is mediated, at least in part, through over-activation of the mammalian target of rapamycin (mTOR) pathway. Knockdown of mTOR, Raptor or Rictor in lal^−/− MDSCs suppressed their stimulation on proliferation of cancer cells, including B16 melanoma, LLC and Tramp-C2 cancer cells. Our results indicate that LAL plays a critical role in regulating MDSCs ability to directly stimulate cancer cell proliferation, and overcome immune rejection of cancer metastasis in allogeneic mice through modulation of the mTOR pathway, which provides a mechanistic basis for targeting MDSCs to reduce the risk of cancer metastasis. Therefore, MDSCs possess dual functions to facilitate cancer metastasis: suppress immune surveillance, and stimulate cancer cell proliferation and growth.