[Hotspots and prospects of esophageal cancer research in China].

Esophageal cancer is a malignant tumor with a high incidence in China. At pesent, advanced esophageal cancer patients are still frequently encountered. The primary treatment for resectable advanced esophageal cancer is surgery-based multimodality therapy, including preoperative neoadjuvant therapy, such as chemotherapy, chemoradiotherapy or chemotherapy plus immunotherapy, followed by radical esophagectomy with thoraco-abdominal two-field or cervico-thoraco-abdominal three-field lymphadenectomy via minimally invasive approach or thoracotomy. In addition, adjuvant chemotherapy, radiotherapy, or chemoradiotherapy, or immunotherapy may also be administered if suggested by postoperative pathological results. Although the treatment outcome of esophageal cancer has improved significantly in China, many clinical issues remain controversial. In this article, we summarize the current hotspots and important issues of esophageal cancer in China, including prevention and early diagnosis, treatment selection for early esophageal cancer, surgical approach selection, lymphadenectomy method, preoperative neoadjuvant therapy, postoperative adjuvant therapy, and nutritional support treatment.

Long non-coding RNA MIR4435-2HG recruits miR-802 from FLOT2 to promote melanoma progression.

OBJECTIVE: The regulatory mechanism of lncRNA MIR4435-2HG has been extensively investigated in human cancers other than melanoma. This study aims to elucidate the role of lncRNA MIR4435-2HG in melanoma. MATERIAL AND METHODS: The mRNA expression was detected by RT-qPCR. MTT assay, Transwell assay and Dual-Luciferase reporter assay were used to investigate the regulatory mechanism of lncRNA MIR4435-2HG. RESULTS: Upregulation of lncRNA MIR4435-2HG was identified in melanoma and promoted melanoma cell proliferation, migration and invasion. In addition, lncRNA MIR4435-2HG serves as the ceRNA of miR-802. MiR-802 inhibited melanoma progression by downregulating lncRNA MIR4435-2HG. Besides, miR-802 directly targets FLOT2. And knockdown of FLOT2 restrained the progression of melanoma by downregulating lncRNA MIR4435-2HG and upregulating miR-802. CONCLUSIONS: LncRNA MIR4435-2HG promotes cell proliferation, migration and invasion in melanoma by sponging miR-802 and upregulating FLOT2.

Distribution of high-risk human papillomavirus genotypes in male attendees at a clinic for sexually transmitted infections in Northern China.

OBJECTIVE: High-risk (HR) human papillomavirus (HPV) is one of the major causes for most anal and penile cancers and oropharyngeal cancers in men, and vaccination against HPV is recommended for the prevention of these cancers. Data on HPV infection in Chinese men is still limited, which requires further investigation to guide vaccine development and assess the effectiveness of HPV vaccines. We thus studied the HR-HPV genotype distribution in HPV-infected men in Northern China. PATIENTS AND METHODS: Genital specimens were obtained from male patients (≥18 years old) at the clinic for sexually transmitted infections of the Shandong Provincial Hospital between January 2016 and December 2018. Samples were analyzed for 15 HR-HPV genotypes, and 2 low-risk HPV (LR-HPV) genotypes using a multiplex real-time quantitive polymerase chain reaction (qPCR) assay. RESULTS: Of 1,163 participants enrolled, 426 patients were diagnosed as verruca acuminata (CA) and 737 were asymptomatic men. The overall prevalence of HPV infection was 42% (489/1,163), and 27.4% (319/1,163) were positive for HR-HPV. HPV 16 (5.2%, 61/1,163) was the most common HR genotype overall, followed by HPV 52 (4.6%, 54/1,163), 51 (4.3%, 50/1,163), 18 (4.1%, 48/1,163), and 39 (4.0%, 47/1,163). Genotypes 16, 52, 39, 51, and 18 were most prevalent in CA patients, and 16, 51, 18, 59, and 39 in asymptomatic men. Prevalence of genotypes 31, 33, and 45 covered by the 9-valent HPV prophylactic vaccine was low in the assessed region. CONCLUSIONS: HPV 16, 52, 51, 18, 39, and 59 were the most common HR genotypes detected in men in Northern China. Importantly, HPV 39, 51, and 59 are not currently covered by either the 4-valent or 9-valent HPV vaccines.

Foxp3 is a key downstream regulator of p53-mediated cellular senescence.

The downstream events and target genes of p53 in the process of senescence are not fully understood. Here, we report a novel function of the forkhead transcription factor Foxp3, which is a key player in mediating T-cell inhibitory functions, in p53-mediated cellular senescence. The overexpression of Foxp3 in mouse embryonic fibroblasts (MEFs) accelerates senescence, whereas Foxp3 knockdown leads to escape from p53-mediated senescence in p53-expressing MEFs. Consistent with these results, Foxp3 expression resulted in the induction of senescence in epithelial cancer cells, including MCF7 and HCT116 cells. Foxp3 overexpression also increased the intracellular levels of reactive oxygen species (ROS). The ROS inhibitor N-acetyl-l-cysteine rescued cells from Foxp3-expression-induced senescence. Furthermore, the elevated ROS levels that accompanied Foxp3 overexpression were paralleled by an increase in p21 expression. Knockdown of p21 in Foxp3-expressing MEFs abrogated the Foxp3-dependent increase in ROS levels, indicating that Foxp3 acts through the induction of p21 and the subsequent ROS elevation to trigger senescence. Collectively, these results suggest that Foxp3 is a downstream target of p53 that is sufficient to induce p21 expression, ROS production and p53-mediated senescence.

[Changes on patterns of sleep duration: findings from China Health and Nutrition Survey in population in 9 provinces].

Objective: To understand the changes on patterns of sleep duration of the China Health and Nutrition Survey (CHNS) cohort in 9 provinces from 2004 to 2011. Methods: Four rounds of CHNS data were used. Urban/rural, age and gender specific insufficient sleeping rates and excessive sleeping rates were analyzed. Results: In 2004, 2006, 2009 and 2011, a total of 274, 281, 329 and 304 children aged 3-5 years; 874, 806, 768 and 742 children aged 6-12 years; 789, 529, 426 and 367 children aged 13-17 years; 9 568, 9 530, 9 942 and 9 609 adults aged ≥18 years were surveyed respectively. The lowest insufficient sleeping rate was 53.9% (200/371) in 3-17 years old children in rural area in 2006, the highest insufficient sleeping rate was 77.2% (44/57) in 3-5 years old children in urban area in 2004. The insufficient sleeping rate increased in rural 3-5 years old children from 2004 to 2011. For the adults aged ≥18 years, the insufficient sleeping rate ranged from 4.2% (82/1 954) in females aged 18-44 years in 2004 and 2009 to 20.8% (211/1 015) in urban residents aged > 60 years in 2011. The insufficient sleeping rate in age-groups 44-59 years and ≥60 years increased in both males and females and in both urban area and rural area from 2004 to 2011. The gender specific excessive sleeping rate in 3-17 years old children was very low in both urban area and rural area and no difference was found in different rounds of survey. The excessive sleeping rate in adults ranged from 18.4% (569/3 093) in urban population in 2011 to 32.5% (1 617/4 969) in females in 2004. The excessive sleeping rate of adult decreased from 2004 to 2011. Conclusion: We should pay attention to the fact that the insufficient sleeping rate in adolescents is high and in increase in rural 3-5 years old children and adults aged ≥45 years.

Role of fibroblast growth factor-23 in the pathogenesis of atherosclerosis in peritoneal dialysis patients.

Several previous studies have demonstrated that elevated levels of fibroblast growth factor-23 (FGF-23) may be involved in atherosclerosis and contribute to the high mortality rate of peritoneal dialysis (PD) patients. The aim of this study was to determine the precise role of FGF-23 in the pathogenesis of atherosclerosis in PD patients. Between April 2009 and January 2012, 62 PD patients and 25 control subjects were included in the study. An enzyme-linked immunosorbent assay was conducted to test for plasma FGF-23 levels. Carotid artery intima-media thickness (CIMT), left ventricular mass index (LVMI), and myocardial performance index (MPI) were determined by ultrasonography. Plasma Ca(2+), P(3+), calcium-phosphorus product, parathyroid hormone, N-terminal pro-brain natriuretic peptide, and cardiac troponin I were also detected. Plasma FGF-23 levels in PD patients were significantly higher than those in control subjects. PD patients with CIMT > 1.0 mm showed the highest levels of FGF-23. Plasma P(3+), calcium-phosphorous product, plasma parathyroid hormone, CIMT, LVMI, and MPI levels were positively associated with plasma FGF-23 levels. Multiple-stepwise regression analyses revealed that plasma P(3+), plasma parathyroid hormone, CIMT, LVMI, and MPI levels were strongly associated with plasma FGF-23 levels. However, no correlations were observed in plasma N-terminal pro-brain natriuretic hormone and cardiac troponin I levels. Plasma FGF- 23 levels may play an important role in the initiation and progression of atherosclerosis. Thus, detecting and defining plasma FGF-23 levels may be a promising biomarker for the early detection of atherosclerosis in PD patients.

A novel antagonist to the inhibitors of apoptosis (IAPs) potentiates cell death in EGFR-overexpressing non-small-cell lung cancer cells.

In the effort to develop an efficient chemotherapy drug for the treatment of non-small-cell lung cancer (NSCLC), we analyzed the anti-tumorigenic effects of a novel small molecule targeting the inhibitor of apoptosis (IAPs), HM90822B, on NSCLC cells. HM90822B efficiently decreased IAP expression, especially that of XIAP and survivin, in several NSCLC cells. Interestingly, cells overexpressing epidermal growth factor receptor (EGFR) due to the mutations were more sensitive to HM90822B, undergoing cell cycle arrest and apoptosis when treated. In xenograft experiments, inoculated EGFR-overexpressing NSCLC cells showed tumor regression when treated with the inhibitor, demonstrating the chemotherapeutic potential of this agent. Mechanistically, decreased levels of EGFR, Akt and phospho-MAPKs were observed in inhibitor-treated PC-9 cells on phosphorylation array and western blotting analysis, indicating that the reagent inhibited cell growth by preventing critical cell survival signaling pathways. In addition, gene-specific knockdown studies against XIAP and/or EGFR further uncovered the involvement of Akt and MAPK pathways in HM90822B-mediated downregulation of NSCLC cell growth. Together, these results support that HM90822B is a promising candidate to be developed as lung tumor chemotherapeutics by targeting oncogenic activities of IAP together with inhibiting cell survival signaling pathways.

INCB018424 induces apoptotic cell death through the suppression of pJAK1 in human colon cancer cells.

Janus kinase (JAK) is one of the main upstream activators of signal transducers and activators of transcription (STAT) that are constitutively activated in various malignancies and are associated with cell growth, survival, and carcinogenesis. Here, we investigated the role of JAKs in colorectal cancer in order to develop effective therapeutic targets for INCB018424, which is the first JAK1/2 inhibitor to be approved by FDA. After examining the basal expression levels of phospho-JAK1 and phospho-JAK2, we measured the effects of INCB018424 on the phosphorylation of JAK1/2 using western blot analysis. Cell viability was determined using the trypan blue exclusion assay. The cell death mechanism was identified by the activation of caspase 3 using western blot and annexin V staining. The basal levels of phospho-JAK1 and phospho-JAK2 were cancer cell type dependent. Colorectal cancer cell lines that phosphorylate both JAK1 and JAK2 include DLD-1 and RKO. INCB018424 inactivates both JAK1 and JAK2 in DLD-1 cells but inactivates only JAK1 in RKO cells. Cell death was proportional to the inactivation of JAK1 but not JAK2. INCB018424 causes caspase-dependent cell death, which is prevented by treatment with z-VAD. The inhibition of JAK1 phosphorylation seemed sufficient to allow INCB018424-mediated apoptosis. JAK1 is a key molecule that is involved in colon cancer cell survival and the inhibition of JAK1 by INCB01424 results in caspase-dependent apoptosis in colorectal cancer cells. The use of selective JAK1 inhibitors could be an attractive therapy against colorectal cancer, but further clinical investigations are needed to test this possibility.

p34 is a novel regulator of the oncogenic behavior of NEDD4-1 and PTEN.

PTEN is one of the most frequently mutated or deleted tumor suppressors in human cancers. NEDD4-1 was recently identified as the E3 ubiquitin ligase for PTEN; however, a number of important questions remain regarding the role of ubiquitination in regulating PTEN function and the mechanisms by which PTEN ubiquitination is regulated. In the present study, we demonstrated that p34, which was identified as a binding partner of NEDD4-1, controls PTEN ubiquitination by regulating NEDD4-1 protein stability. p34 interacts with the WW1 domain of NEDD4-1, an interaction that enhances NEDD4-1 stability. Expression of p34 promotes PTEN poly-ubiquitination, leading to PTEN protein degradation, whereas p34 knockdown results in PTEN mono-ubiquitination. Notably, an inverse correlation between PTEN and p34/NEDD4-1 levels was confirmed in tumor samples from colon cancer patients. Thus, p34 acts as a key regulator of the oncogenic behavior of NEDD4-1 and PTEN.

SVCT-2 in breast cancer acts as an indicator for L-ascorbate treatment.

L-ascorbate (L-ascorbic acid, vitamin C) clearly has an inhibitory effect on cancer cells. However, the mechanism underlying differential sensitivity of cancer cells from same tissue to L-ascorbate is yet to be clarified. Here, we demonstrate that L-ascorbate has a selective killing effect, which is influenced by sodium-dependent vitamin C transporter 2 (SVCT-2) in human breast cancer cells. Treatment of human breast cancer cells with L-ascorbate differentially induced cell death, dependent on the SVCT-2 protein level. Moreover, knockdown of endogenous SVCT-2 via RNA interference in breast cancer cells expressing high levels of the protein induced resistance to L-ascorbate treatment, whereas transfection with SVCT-2 expression plasmids led to enhanced L-ascorbate chemosensitivity. Surprisingly, tumor regression by L-ascorbate administration in mice bearing tumor cell xenograft also corresponded to the SVCT-2 protein level. Interestingly, SVCT-2 expression was absent or weak in normal tissues, but strongly detected in tumor samples obtained from breast cancer patients. In addition, enhanced chemosensitivity to L-ascorbate occurred as a result of caspase-independent autophagy, which was mediated by beclin-1 and LC3 II. In addition, treatment with N-acetyl-L-cysteine, a reactive oxygen species (ROS) scavenger, suppressed the induction of beclin-1 and LC3 II, implying that the differential SVCT-2 protein-dependent L-ascorbate uptake was attributable to intracellular ROS induced by L-ascorbate, subsequently leading to autophagy. These results suggest that functional SVCT-2 sensitizes breast cancer cells to autophagic damage by increasing the L-ascorbate concentration and intracellular ROS production and furthermore, SVCT-2 in breast cancer may act as an indicator for commencing L-ascorbate treatment.

Design and performance testing of an axial-flow ventricular assist device developed at the Fu Wai Hospital in Beijing.

PURPOSE: Various ventricular assist devices (VADs) have been developed for clinical use in recent years. The aim of a multidisciplinary research team at the Fuwai Hospital of the Peking Union Medical College is to design and develop an axial flow left ventricular assist device (LVAD) for adults. METHODS: Using Computational Fluid Dynamics (CFD), the inflow characteristics of the axial flow pump were analyzed. After CFD analysis, the axial pump was fabricated using a 5-axis, computer numerical control (CNC) milling machine. Performances of the pump both in vitro and in vivo were tested. RESULTS: This VAD, which was developed after numerous CFD analyses for the flow characteristics of the pump, is 58.5 mm long, 30 mm wide and weighs 120 g. The pump can deliver 5 lpm for pressures of 100 mmHg over 8500 rpm. The NIH value was 0.01 g/100 L. The hemolysis, which was evaluated in an in vivo test, was a bit higher than the normal value, but remained within an acceptable range. CONCLUSIONS: Performance of the pump in vitro and in vivo was considered sufficient for an LVAD. Further design improvements are being undertaken in terms of hemolysis and thrombosis to improve the biocompatibility of the pump.

Heteropolymorphism of mitochondrial NADH dehydrogenase subunit 3 gene for the population analysis of chum salmon, Oncorhynchus keta.

Mitochondrial DNAs (mtDNAs) has been frequently used as genetic markers for the population genetic studies. In this study we used chum salmon (Oncorhynchus keta) from Korea, Japan andAmerica, and compared their mitochondrial NADH dehydrogenase subunit 3 (ND3) genes by DNA sequence analysis. Sequence variation was studied in the ND3 among total 11 individuals from three populations. The ND3 gene was amplified by PCR targeting parts of cytochrome oxidase III gene (COIII) and NADH dehydrogenase subunit 4L gene (ND4L). ND3 gene sequence, encoded 752 bps, presented some genetic variation in the chum salmon populations. The observed nucleotide variations inferred the distinct genetic differentiation of American salmons from Korean and Japanese chum salmons. Six sites of single nucleotide polymorphism (SNP) were explored in the ND3 locus. Denaturing gradient gel electrophoresis analysis also showed a clear heterogenous band in American salmons compared to Asian salmons.

Young C3H mice infected with Toxoplasma gondii are a novel experimental model of communicating hydrocephalus.

The effects of leptomeningeal inflammation on the development of hydrocephalus are less understood than those of obstructing the flow of cerebrospinal fluid (CSF) in animal models. We succeeded in introducing a novel experimental model of hydrocephalus and analysed changes in histopathology and CSF flow in mice infected with an avirulent Fukaya strain of Toxoplasma gondii (T. gondii). Six to 7 week-old male mice were orally inoculated with a brain homogenate containing ten T. gondii cysts. The cerebral ventricles became enlarged in all C3H/HeN and C57BL/6 mice 4 weeks after T. gondii infection, but mildly in BALB/c mice. In addition to the lateral ventricle, the third and fourth ventricles and Sylvian aqueducts were dilated in all mice. Lymphocytes and monocytes infiltrated the subarachnoid space. Indian ink particles required more time to pass from the lateral ventricle to the cervical lymph nodes, although they reached the subarachnoid space. Computed tomography ventriculography demonstrated that the CSF was not obstructed during passage through the ventricular systems, but contrast remained static in the lateral ventricle only in infected mice. These results indicated that the infected mice developed communicating type hydrocephalus without obstructive or mass lesions in the ventricles. The hydrocephalus that arises in mice infected with T. gondii is considered a consequence of leptomeningeal inflammation that blocks CSF circulation at the subarachnoid space, implying that leptomeningeal inflammation is important in other types of hydrocephalus.

Lancefield group C Streptococcus dysgalactiae infection responsible for fish mortalities in Japan.

A Lancefield serological group C Streptococcus sp. was isolated from cultured amberjack, Seriola dumerili Risso, and yellowtail, Seriola quinqueradiata Temminck and Schlegel, immunized with Lactococcus garvieae commercial vaccines in Japan. The isolated bacteria were Gram-positive cocci, auto-aggregating in saline, morphologically long chains in growth medium, catalase negative and alpha-haemolytic on blood agar. An almost complete gene sequence of the 16S rDNA of two isolates was determined and compared with that of bacterial strains in the database. The isolates were identified as Streptococcus dysgalactiae based on the results of the 16S rDNA sequence, the bacteriological properties and the Lancefield serological grouping. Oligonucleotide primers specifically designed for the 16S-23S rDNA intergenic spacer region of S. dysgalactiae amplified a gene from all the fish isolates, as well as the type strains alpha-haemolytic S. dysgalactiae subsp. dysgalactiae ATCC430738 and beta-haemolytic S. dysgalactiae subsp. equisimilis ATCC35666, but not those of S. equi ATCC33398, Lactococcus garvieae ATCC43921 and L. garvieae KG9408. The severe necrotic lesions of the caudal peduncle seen in experimentally infected fish were similar to those seen in naturally infected fish.

Inhibitory effect of protein hydrolysates on calcium carbonate crystallization.

Protein hydrolysates, prepared by enzymatic digestion of soybean protein and egg white albumin using several proteases, inhibited the crystal growth of calcium carbonate. Each hydrolysate showed different inhibitory activities, suggesting the key role of peptide structures in the inhibition. The deamidation of protein hydrolysates by glutaminase increased not only the inhibitory activity toward the crystal growth of calcium carbonate but also the resistance of the hydrolysates against peptic digestion. Furthermore, the addition of sodium chloride, citric acid, or lactose into the reaction mixture enhanced the inhibitory activity. The protein hydrolysates inhibited both nucleation and crystal growth of calcium carbonate and also affected the crystal morphology.

Developmental expression, subcellular localization, and tyrosine phosphorylation of NR2A and NR2B in the rat brain.

We carried out quantitative analyses of the developmental expression, subcellular localization of the N-methyl-D-aspartate receptor subunit 2A (NR2A) and 2B (NR2B), and tyrosine phosphorylation of NR2B. Immunoblot analyses showed that NR2A was not detected during the embryonic period and the first postnatal week but its expression reached 63.90% of adult at P14 and continued to increase until the fourth week, reaching a maximum at P30 (110% of adult). The NR2B was detected from as early as E14 (2.65% of adult) and its expression was transiently elevated at birth (43.73% of adult), decreasing for the first postnatal week, and then increased again rapidly in the second week (105.45% of adult at P14) with a maximum at P30 (123.34% of adult). There were 2.26 +/- 0.40-fold more NR2B than NR2A proteins in the forebrain PSD fractions, and NR2A and NR2B were enriched 2.75 +/- 0.35 and 4.65 +/- 0.25 fold, respectively, in the synaptosome, and 13.75 +/- 0.80 and 16.04 +/- 0.25-fold, respectively, in the PSD fraction from brain homogenate. The tyrosine phosphorylation of NR2B reached an adult level at around birth declining in the first postnatal week but recovered to the adult level by the end of the second week, while the amount of the protein itself increased 2.28-fold after birth, indicating that only a fraction of the proteins are phosphorylated in vivo. Our results indicate that expression and tyrosine phosphorylation of NR2B might be important for NMDA receptor functions in embryonic and early postnatal development.

Immunoblot analyses on the differential distribution of NR2A and NR2B subunits in the adult rat brain.

Quantitative immunoblot analyses were carried out to study the distribution of N-methyl-D-aspartate (NMDA) receptor subunit 2A and 2B (NR2A and NR2B, respectively) at the protein level in the adult rat brain. Highest levels of NR2A were detected in cerebral cortex and hippocampus, followed at more or less similar levels (about 36-72% of cerebral cortex) by striatum, thalamus, olfactory bulb, superior and inferior colliculi, and cerebellum. The lowest levels were detected in midbrain and lower brain stem (30-31% of cerebral cortex). The NR2B was more dramatic in differential distribution than the NR2A. Highest levels of NR2B were found in telencephalic (olfactory bulb, cerebral cortex, hippocampus, and striatum) and thalamic regions, and expression in superior and inferior colliculi, midbrain, lower brain stem, and cerebellum were significantly lower (4-25% of cerebral cortex). Interestingly, NR2B proteins were barely detectable in the cerebellum. When the postsynaptic density (PSD) fractions were compared, the amount of NR2B in the cerebellar PSD fraction was only 1.8% of that present in the cerebral PSD fraction where the subunit is highly enriched. Immunoblot analyses with a phosphotyrosine-specific antibody showed that the molecular sizes of major phosphotyrosine-containing proteins in forebrain and hindbrain are 180 and 45 kDa, respectively. The regional distribution of the 180 kDa major phosphotyrosine protein was very similar to that of NR2B, and the protein could be immunoprecipitated by NR2B antibody. Our data shows that NR2A and NR2B subunits are differentially distributed in the brain in an overlapping manner, and that the major phosphotyrosine-containing protein of 180 kDa in forebrain is the NR2B.