[Clinical analysis of minimal invasive surgical treatment for pancreatic neuroendocrine tumors]

Objective: To analyze the safety and effectiveness of minimal invasive surgery treating pancreatic neuroendocrine tumors (pNETs), and to summarize surgical characteristics and share experience. Methods: The clinical data of 80 pNETs treated by a single hospital from January 2015 to December 2019 were retrospectively analyzed. The patients were divided into laparoscopic group and robot group. And surgical procedures included pancreaticoduodenectomy (PD), distal pancreatectomy (DP), central pancreatectomy (CP), and tumor enucleation. Results: Of 80 patients, 76 cases (95%) underwent minimal invasive surgery and 4 cases (5%) changed to open surgery. There were 38 females, with median age of 54.4 (20-80) years and median BMI (17.0-38.0) kg/m(2). Among them, 24 patients (31.6%) underwent PD, 36 patients (47.4%) underwent DP, 8 patients (10.5%) underwent CP and 8 patients (10.5%) received tumor enucleation. The postoperative incidence of grade B/C pancreatic fistula was 35.5%, the incidence of abdominal infection was 10.5%, the postoperative bleeding was 7.9%, and the reoperation rate was 6.6%, without perioperative deaths. There was no significant difference in postoperative complications among different surgical methods, including postoperative pancreatic fistula (P=0.396), postoperative bleeding (P=0.297), postoperative abdominal infection (P=0.339) and reoperation (P=0.396). Conclusions: Surgical resection is an effective treatment for pNETs. pNETs are suitable for minimally invasive surgery with earlier stage and smaller tumor diameter. Minimally invasive surgery for pNETs is safe and feasible, and functional preserving surgery could take into consideration.

MiR-21 promotes fracture healing by activating the PI3K/Akt signaling pathway

OBJECTIVE

This study aims to elucidate the potential mechanism of micro ribonucleic acid (miR)-21 in promoting fracture healing.

MATERIALS AND METHODS

30 male Sprague-Dawley rats were randomly divided into group A (phosphate-buffered saline, PBS, n=10), group B (AntagomiR-21, n=10) and group C (AntagomiR-NC, n=10) according to the different treatments. The femoral fracture operation was performed in every rat, which was pathologically diagnosed via X-ray. After the successful modeling, 50 μL (2 nmoL) PBS, 50 μL AntagomiR-21 or 50 μL AntagomiR-NC was intraperitoneally injected into rats in group A, B or C, respectively. The above agents were injected once a week for 6 weeks. At 6 weeks, 3 rats were executed in each group, and the tissue at the fracture end was observed via hematoxylin-eosin (HE) staining. The fracture healing of rats was evaluated via imaging at 1 and 7 weeks. At the same time, the expression of miR-21 in the three groups was detected via Reverse Transcription-Polymerase Chain Reaction (RT-PCR), and the expression of phosphatidylinositol 3-hydroxy kinase (PI3K) and phosphorylated-serine/threonine-protein kinase B (p-Akt) in the three groups was detected via Western blotting.

RESULTS

According to the histological staining, the bone repair at the fracture end of rats in group B was not significant with fracture and poor continuity compared with those in group A and group C. The imaging evaluation revealed that in group B, the callus tissues were significantly reduced, the fracture line had undesirable healing. There were no displacement and loosening of internal fixation compared with group A and group C. Besides, RT-PCR showed that the miR-21 expression declined markedly in group B compared with that in group A and group C, and the differences were statistically significant (p<0.05). Western blotting manifested that the protein levels of PI3K and p-Akt also declined in group B compared with those in group A and group C, and there were statistically significant differences (p<0.05).

CONCLUSIONS

MiR-21 promotes the fracture healing in fractured rats by activating the PI3K/Akt signaling pathway.

[Early experience of minimal invasive surgery for adolescent with pancreatic head tumor: a report of 15 cases]

Objective: To summarize the characteristics and difficulties of minimal invasive surgery for adolescent with pancreatic head tumor. Methods: The data of adolescent younger than 28 years old with pancreatic head tumor treated at Department of Gastroenterology and Pancreatic Surgery, Zhejiang Province People's Hospital from January 2014 to December 2019 were analyzed retrospectively. Fifteen cases were enrolled, included 5 males and 10 females. The median age was 20 years(range: 11 to 27 years) and the body mass index was (19.8±2.3)kg/m(2)(range: 17.3 to 21.6 kg/m(2)). Results: Standard pancreaticoduodenectomy was performed in 12 cases, including 9 cases of laparoscopic surgery and 3 cases of robotic-assisted surgery, and laparoscopic pancreaticoduodenectomy with resection of hepatic flexure of colon was performed on 1 case, and robotic-assisted duodenum-preserving pancreatic head resection with pancreatogastrostomy was performed on other 2 cases. The operative time was (269.0±65.1)minutes(range: 150 to 410 minutes), and the blood loss was (135.6±52.7)ml(range: 50 to 400 ml). Six patients got postoperative complications with gastrointestinal bleeding biochemical leakage and intestinal obstruction(n=1), pancreatic biochemical leakage(n=1), bile leakage(n=1), chylous leakage(n=1), wound infection(n=1), hepatic injury(n=1). The median postoperative hospital stay was 13 days(range: 9 to 22 days).The pathologic findings were solid pseudopapillary neoplasms(n=8), neuroendocrine neoplasms(n=3), introductal papillary mucinous neoplasm(n=1), cystic fibroma(n=1), serous cystadenoma(n=1), Ewing sarcoma(n=1).The median follow-up was 37 months(range: 2 to 75 months).The patient with Ewing sarcoma was diagnosed as liver metastasis at 41 months after surgery and died at 63 months after surgery.All the other patients survived without tumor.Three patients got the long-term complication of bile duct. Conclusions: Most of pancreatic head tumors for adolescent are benign or low malignant. Minimally invasive surgery be the first choice, and function-preserving surgery should be taken into account as much as possible.Perioperative management and communication is essential as the parents pay much attention to the quality of life after surgery.

Inactivation of airborne porcine reproductive and respiratory syndrome virus (PRRSv) by a packed bed dielectric barrier discharge non-thermal plasma

Porcine reproductive and respiratory syndrome virus (PRRSv) is one of the most significant airborne viruses impacting the pork industry in the US. Non-thermal plasmas (NTPs) are electrical discharges comprised of reactive radicals and excited species that inactivate viruses and bacteria. Our previous experiments using a packed bed NTP reactor demonstrated effective inactivation of bacteriophage MS2 as a function of applied voltage and power. The present study examined the effectiveness of the same reactor in inactivating aerosolized PRRSv. A PRRSv solution containing ∼10⁵ TCID₅₀/ml of PRRSv VR2332 strain was aerosolized at 3 ml/min by an air-jet nebulizer and introduced into 5 or 12 cfm air flow followed by NTP exposure in the reactor. Twin impingers upstream and downstream of the reactor collected samples of the virus-laden air flow for subsequent TCID₅₀ assay and qPCR analyses. An optical particle sizer measured upstream and downstream aerosol size distributions, giving estimates of aerosol filtration by the reactor. The results showed that PRRSv was inactivated to a similar degree as MS2 at the same conditions, with the maximum 1.3-log inactivation of PRRSv achieved at 20 kV and 12 cfm air flow rate. The results demonstrate the potential of properly optimized NTPs in controlling PRRSv transmission.

[Laparoscopic gastroduodenostomy with manual suture for Billroth Ⅰ anastomosis: a report of 36 cases]

Objective: To examine the clinical efficiency of laparoscopic gastroduodenostomy with BillrothⅠanastomosis with manual suture. Methods: The clinic data of 36 patients with gastric cancer who underwent laparoscopic gastroduodenostomy with Billroth Ⅰ anastomosis from November 2017 to September 2019 in Department of Gastrointestinal and Pancreatic Surgery, Zhejiang Provincial People's Hospital were analyzed retrospectively.There were 22 males and 14 females, aged (64.3±9.3) years(range: 43 to 80 years), underwent complete laparoscopic gastroduodenostomy. The laparoscopic manual suture was used for Billroth Ⅰ anastomosis. Results: All the laparoscopic radical gastrectomy and manual suturing gastroduodenostomy were successfully performed. The operation time was (226.7±40.4) minutes (range: 180 to 320 minutes), including (24.8±7.1) minutes (range: 15 to 48 minutes) for gastroduodenostomy.There was (3.8±0.9) days (range: 2 to 6 days) for anal exhaust, (5.7±2.0) days (range: 3 to 13 days) for extubation of gastric tube, and (10.3±3.1) days (range: 7 to 19 days) for hospitalization. There was no death in perioperative period. Postoperative pathological report showed 3 cases of highly differentiated adenocarcinoma, 5 cases of moderately differentiated adenocarcinoma, 22 cases of poorly differentiated adenocarcinoma and 6 cases of signet ring cell carcinoma, including 27 cases in T1 stage and 9 cases in T2 stage. The number of lymph nodes harvested was 36.4±8.9 (range: 23 to 60). Lymph node metastasis was positive in 7 cases and negative in 29 cases. TNM stage included 24 cases in ⅠA stage, 8 cases in ⅠB stage and 4 cases in Ⅱ stage. After the operation, the upper digestive tract radiography showed that the anastomosis opening was unobstructed without complications such as anastomotic stenosis. Conclusion: Laparoscopic gastroduodenostomy with Billroth Ⅰ anastomosis with manual suture is safe and feasible, has a good short-term effect.

[The role of abnormal mitochondrial fusion and fission in PBDE-47-induced change in mitochondrial mass in PC12 cells]

Objective: To investigate the effect of 2, 2', 4, 4'-tetrabromodiphenyl ether (PBDE-47) on the mitochondrial mass in rat adrenal pheochromocytoma (PC12) cells and the potential mechanisms. Methods: Highly differentiated PC12 cells were divided into control, 1, 10 or 20 μmol/L PBDE-47-treated groups and cultured for 24 h. Transmission electron microscopy was employed to observe the changes in mitochondrial morphology and quantity in PC12 cells. Flow cytometry was used to measure the fluorescence intensity of Nonyl Acridine Orange (NAO) , a fluorescent indicator of mitochondrial membrane cardiolipin, to reflect mitochondria mass. Western blotting was used to determine the expression levels of Mitofusion 1 (Mfn1) and Fission 1 (Fis1) proteins. To further explore the role of abnormal mitochondrial fusion and fission in PBDE-47-induced mitochondrial mass changes, PC12 cells were divided into control group, 5 μmol/L M1 treatment group, 20 μmol/L PBDE-47 treatment group and 5 μmol/L M1+20 μmol/L PBDE-47 combined treatment group and cultured for 24 h, then the fluorescence intensity of NAO and expression levels of Mfn1 and Fis1 proteins were detected. Results: The control group showed numerous mitochondria with normal morphology, while the number of mitochondria decreased after PBDE-47 treatment. Especially, the disappeared cristae, swelling and vacuoles of mitochondria and decreased fluorescence intensity of NAO (P<0.05) were observed in 10 and 20 μmol/L PBDE-47-treated groups. Meanwhile, the expression levels of Mfn1 and Fis1 proteins in the 10 and 20 μmol/L PBDE-47-treated groups were significantly decreased compared with control group (P<0.05) . However, 5 μmol/L M1 co-treatment with 20 μmol/L PBDE-47 significantly increased the levels of Mfn1 and Fis1 proteins and fluorescence intensity of NAO compared with the 20 μmol/L PBDE-47 group (P<0.05) . Conclusion: PBDE-47 can inhibit the mitochondrial fusion and fission process, thus leading to damage of mitochondria mass in PC12 cells.

Inactivation of airborne viruses using a packed bed non-thermal plasma reactor

Outbreaks of airborne infectious diseases such as measles or severe acute respiratory syndrome can cause significant public alarm. Where ventilation systems facilitate disease transmission to humans or animals, there exists a need for control measures that provide effective protection while imposing minimal pressure differential. In the present study, viral aerosols in an airstream were subjected to non-thermal plasma (NTP) exposure within a packed-bed dielectric barrier discharge reactor. Comparisons of plaque assays before and after NTP treatment found exponentially increasing inactivation of aerosolized MS2 phage with increasing applied voltage. At 30 kV and an air flow rate of 170 standard liters per minute, a greater than 2.3 log reduction of infective virus was achieved across the reactor. This reduction represented ~2 log of the MS2 inactivated and ~0.35 log physically removed in the packed bed. Increasing the air flow rate from 170 to 330 liters per minute did not significantly impact virus inactivation effectiveness. Activated carbon-based ozone filters greatly reduced residual ozone, in some cases down to background levels, while adding less than 20 Pa pressure differential to the 45 Pa differential pressure across the packed bed at the flow rate of 170 standard liters per minute.

Characterization of fungal microbiota on normal ocular surface of humans

OBJECTIVES

Our objective was to characterize the fungal microbiota on normal ocular surface of humans with the culture-based method and high-throughput sequencing approach.

METHODS

A total of 45 adults were recruited from an urban community, and 90 conjunctival swabs were obtained, one from each eye of each participant. One of the two swabs from each participant was randomly chosen and allocated to internal transcribed spacer (ITS) sequencing, and the other was subjected to conventional fungal cultivation.

RESULTS

Four filamentous fungi were isolated from the 45 samples using the culture-based method, Penicillium citrinum, Aspergillus niger, Phialophora and Trichoderma. In the other 45 samples, 18 samples were positive for PCR amplification and sent for subsequent ITS sequencing. A total of 518 703 valid reads were generated and assigned into 467 operational taxonomic units. Overall, 4 phyla and 94 genera were identified. Two phyla, Basidiomycota (78.67%) and Ascomycota (19.54%), and five genera, Malassezia (74.65%), Rhodotorula (1.93%), Davidiella (1.89%), Aspergillus (1.25%) and Alternaria (0.61%), which accounted for >80% of the fungal microbiome and presented in >80% of the individuals tested, constituted the possible 'core fungal taxa' on normal ocular surface.

CONCLUSIONS

The fungal microbiome on normal ocular surface of humans was identified using the high-throughput sequencing method, providing a basis for further investigations on the potential role of the fungal microbiota in ocular health and disease.

Plasma cell-free DNA integrity plus circulating tumor cells: a potential biomarker of no distant metastasis breast cancer

Cell-free DNA integrity (cfDI) is a promising diagnostic and prognostic biomarker in breast cancer. However, no specific study has evaluated the diagnostic ability of cfDI in patients with no distant metastasis breast cancer (no-MBC) and benign breast tumor (BBT) to date. We assessed the plasma cfDI of 84 patients with no-MBC and 30 patients with BBT using quantitative PCR and compared it with circulating tumor cells (CTCs) and carbohydrate antigen 153 (CA153). The no-MBC group had significantly lower mean cfDI (0.58) than the BBT group (0.74, p = 0.004). Subgroup analysis showed that decreased cfDI seem to be associated with risk factors such as age 14% (mean cfDI = 0.57), tumor size > 2 cm (mean cfDI = 0.58), and positive lymph node status (mean cfDI = 0.56), but had no statistical significance. McNemar's test suggested that cfDI had stronger diagnostic power than CTCs, cfDNA concentration, or CA153 (p < 0.001). Spearman's rho showed that the correlation coefficient between cfDI and CTCs was 0.278 (p = 0.04) in the no-MBC group. Receiver operating characteristic curve analysis also suggested that cfDI was superior to CTCs or CA153. Combined with CTCs, cfDI reduced the false positive rate from 50% to 10.71% and increased the area under the curve value from 0.66 to 0.68. Our results suggest that cfDI is a potential diagnostic biomarker of no-MBC. Using cfDI and CTCs as a combined diagnostic tool for no-MBC could improve diagnostic sensitivity and specificity but more samples will be needed.

[Predictive value of cytokines and procalcitonin on infection in children with hematological malignancies]

Objective: To explore the value of cytokines and procalcitonin (PCT) in predicting the potential pathogen and the severity of infection in children with hematological malignancies. Methods: This was a prospective cohort study. A total of 1 543 children (3 912 episodes) with hematological malignancies admitted to the Department of Hematology/Oncology in Children's Hospital of Zhejiang University School of Medicine from November 2010 to June 2018 were prospectively enrolled in this study. According to the pathogen, the patients were divided into sepsis group with positive blood culture (380 patients/608 episodes), sepsis group with negative blood culture (539/1 484), non-septic infection group (549/1 709), viral infection group (18/21) and fungal infection group (57/90). The patients were also divided into two groups in either shock group (171/187) or non-shock group (1 372/3 725). Meanwhile, 89 children (112 episodes) with matched hematological malignancies without fever were enrolled as the control group. The levels of PCT and cytokines were measured for detecting the potential relationship between these markers and infection severity. Mann-Whitney U test or Kruskal-Wallis H test was used to compare the differences between groups. The Receiver Operator Characteristic curve analysis was used to explore the predictive value. Results: (1) There were significantly higher levels of interleukin (IL) 6 (H=210.002, P<0.01), IL-10 (H=223.045, P<0.01), and PCT (H=76.799, P<0.01) in the infection group, with area under curre (AUC) of 0.67 (95%CI 0.64-0.69), 0.69 (95%CI 0.66-0.71) and 0.59 (95%CI 0.56-0.61), respectively. (2) Among the patients in the shock group, IL-6 (Z=11.460, P<0.01), IL-10 (Z=14.242, P<0.01) and PCT (Z=10.813, P<0.01) were significantly higher than those in the non-shock group, with the AUC of 0.75 (95%CI 0.70-0.79), 0.81 (95%CI 0.77-0.84) and 0.73 (95%CI 0.69-0.77), respectively. (3) In patients with septic shock, the incidence of Gram negative bacteria (GNB) infection (60 episodes) was significantly higher than Gram positive bacteria (GPB) infection (22 episodes) (χ(2)=29.665, P<0.01). The AUC of IL-6, IL-10 and PCT for predicting GNB infection were 0.75 (95%CI 0.72-0.78), 0.82 (95%CI 0.79-0.85) and 0.67 (95%CI 0.63-0.70), respectively. (4) The predictive power of IL-6, IL-10 and PCT combination (AUC=0.994) was superior to IL-10 alone (AUC=0.810) in predicting septic shock (Z=10.211, P<0.01). Conclusions: IL-6 and IL-10 are better predictors of GNB infection than PCT in hematology-oncology children. Furthermore, the combination of these two cytokines and PCT is more valuable in predicting the severity of infection.

Comparative analysis of the blood transcriptomes between wolves and dogs

Dogs were domesticated by human and originated from wolves. Their evolutionary relationships have attracted much scientific interest due to their genetic affinity but different habitats. To identify the differences between dogs and wolves associated with domestication, we analysed the blood transcriptomes of wolves and dogs by RNA-Seq. We obtained a total of 30.87 Gb of raw reads from two dogs and three wolves using RNA-Seq technology. Comparisons of the wolf and dog transcriptomes revealed 524 genes differentially expressed genes between them. We found that some genes related to immune function (DCK, ICAM4, GAPDH and BSG) and aerobic capacity (HBA1, HBA2 and HBB) were more highly expressed in the wolf. Six differentially expressed genes related to the innate immune response (CCL23, TRIM10, DUSP10, RAB27A, CLEC5A and GCH1) were found in the wolf by a Gene Ontology enrichment analysis. Immune system development was also enriched only in the wolf group. The ALAS2, HMBS and FECH genes, shown to be enriched by the Kyoto Encyclopedia of Genes and Genomes analysis, were associated with the higher aerobic capacity and hypoxia endurance of the wolf. The results suggest that the wolf might have greater resistance to pathogens, hypoxia endurance and aerobic capacity than dogs do.

Three-vessel-trachea view in the diagnosis of fetal cardiac great vessel malformation

Fetal cardiac great vessel malformation is attracting increasing attention in the prenatal ultrasonic diagnosis of fetal congenital heart disease. To investigate the clinical diagnostic values of three-vessel-trachea view (3VT view) in the ultrasonic diagnosis of this malformation, the present study analyzed the echocardiographic examination results of 77 fetuses with great vessel malformation, retrospectively analyzed the echocardiographic characteristics in the three-vessel-trachea view, and followed up the enrolled cases. The results suggest that great vessel malformation had characteristic manifestations, such as abnormal arrangement order, inner diameter, blood flow direction and branch. Color Doppler flow imaging found V, O, C, U, Ioo and oVo structures. There were 20 cases of blood vessel position abnormality, 38 cases of abnormal blood vessel diameter, and 19 cases of abnormal number of blood vessels. The detection rate of abnormal blood vessel diameter was 95%, which was the highest; the detection rate of abnormal blood vessel position was 97.4%, and that of abnormal number of blood vessels was 84.2%. It is concluded that the 3VT view can indicate fetal cardiac great vessel malformation. The 3VT view is beneficial to timely prenatal diagnosis, relief of body pain and improvement of quality of birth.

Available energy content, nutrients digestibility of chili meal and effects on performance of growing pigs

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Chili meal is classified as a roughage due to its high dietary fiber content.

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Chili meal has moderate DE, ME and nutrients digestibility for growing pigs.

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Addition of chili meal have adverse effect on ADG and ATTD of nutrients.

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The combination of 50 g/kg chili meal and proper soybean has no significant negative effects for growing pigs.

The objective of this study was to evaluate the digestible energy (DE), metabolizable energy (ME) content, apparent total tract digestibility (ATTD) of nutrients in chili meal (CM), and to determine the effects of CM on the performance of growing pigs. In Exp. 1, 12 barrows (Duroc x Landrace x Yorkshire) with an initial body weight (BW) of 50.9 ± 1.8 kg were allocated to one of two treatments, corn-soybean meal basal diet or diet containing 194.2 g/kg CM, which replaced corn and soybean meal in the basal diet. Pigs were placed in metabolism crates for a 7-d adaptation period followed by a 5-d total collection of feces and urine to detect DE, ME and ATTD of nutrients in CM. Exp. 2 was conducted for 4 wk. to evaluate the effect of CM on performance of growing pigs. 150 growing pigs (58.4 ± 1.2 kg BW) were allocated to 1 of 5 treatments. Treatment 1 was a corn-soybean meal basal diet met the DE requirement for growing pigs recommended by NRC (2012). Treatment 2 or 3 were diets containing 50 g/kg or 100 g/kg CM respectively. Treatment: 4 or 5 were based on treatment 2 or 3, while soybean oil (SBO) was added to improve the DE content to that in treatment 1. In Exp. 1, the DE and ME content of CM were 9.08 and 8.48 MJ/kg. The ATTD of dry matter (DM), gross energy (GE), organic matter (OM) and neutral detergent fiber (NDF) were 0.60, 0.54, 0.66 and 0.38, respectively. In Exp. 2, addition of CM linearly decreased (P < 0.05) average daily gain (ADG) and the ATTD of DM, GE and OM while ATTD of crude protein (CP) had a quadratic (P < 0.05) change. When SBO was supplemented in diets containing CM, greater values (P < 0.05) of ATTD of most nutrients were observed. With the dietary inclusion of CM, the albumin/globulin ratio in serum had a quadratic change (P < 0.05), and the level of low-density cholesterol linearly (P < 0.05) increased. In treatments with 50 g/kg CM, a significant reduction (P < 0.05) of total antioxidant capacity was found in diet formulated with SBO. In treatments with 100 g/kg CM, the level of total cholesterol was lower (P < 0.05) in the diet with SBO. In conclusion, CM had moderate energy density and nutrients digestibility in pig diets. 50 g/kg CM with SBO in diets could be fed to growing pigs with no significant negative effects.

A monoclonal antibody targeting ErbB2 domain III inhibits ErbB2 signaling and suppresses the growth of ErbB2-overexpressing breast tumors

The anti-ErbB2 antibodies trastuzumab and pertuzumab in combination have recently been approved for the treatment of patients with ErbB2-positive metastatic breast cancer. Pertuzumab, which binds to ErbB2 near the center of domain II, and trastuzumab, which binds to the juxtamembrane region of ErbB2 domain IV, directly interfere with domain II- and domain IV-mediated heterodimerization contacts, respectively. In this study, we report a novel anti-ErbB2 antibody, 3E10, which binds to an epitope in domain III that appears to be located opposite to the dimerization interfaces in domain II and domain IV of ErbB2. Our data show that the 3E10 antibody inhibits ErbB2 heterodimerization via a mechanism that strikingly differs from trastuzumab and pertuzumab. It could be speculated that the 3E10 antibody may affect ErbB2 heterodimerization by causing major conformational changes of ErbB2. Furthermore, 3E10 provides synergistic inhibition of ErbB2 heterodimerization and signaling in combination with either trastuzumab or pertuzumab. The combination of these three anti-ErbB2 antibodies that have complementary mechanisms of action appears to be an extremely potent ErbB2 heterodimerization blocker. Compared with trastuzumab plus pertuzumab, the combination of trastuzumab, pertuzumab and 3E10 provides a more potent blockade of ErbB2 signaling. Consistent with this, trastuzumab plus pertuzumab plus 3E10 results in greater in vitro and in vivo antitumor activity in ErbB2-overexpressing breast tumor models, suggesting its potential use for treating ErbB2-overexpressing breast cancer.

Karyotype studies on Lycoris radiata populations from China

Lycoris radiata is an important medicinal and ornamental plant of China. In the present study, somatic chromosome counts and karyotype analyses, which are important aspects of plant phylogeny and evolution, were performed in 466 individuals from 25 L. radiata populations by root tip squash method. Chromosome counts revealed that 10 populations were diploid (2n = 2x = 22) and 15 were triploid (2n = 3x = 33). Except for one diploid population containing some triploid plants, the remaining 24 populations showed a single cytotype. Karyotype analysis showed that the karyotypes of L. radiata varied in different populations and even within the same population. However, based on the Stebbins' system, the karyotype of all the populations could be classified in 4A classes. The cluster analysis and ordination methods demonstrated that the L. radiata populations grouped in two major clusters. Previous research has shown that the triploid strain of L. radiata is a genetically identical species. However, the cluster analysis revealed that the triploid strains clustered in two groups instead of one, which indicates that these strains may not be identical species, genetically. This study is expected to improve the understanding of the genetic diversity in L. radiata and provide a basis for future studies on species differentiation, speciation, and taxonomy.

HGF/Met and FOXM1 form a positive feedback loop and render pancreatic cancer cells resistance to Met inhibition and aggressive phenotypes

Purpose

Hepatocyte growth factor (HGF)/Met signaling plays critical roles in pancreatic ductal adenocarcinoma (PDA) development and progression and is considered a potential therapeutic target for this disease. However, the mechanism of aberrant activation of HGF/Met signaling and resistance to Met inhibition in PDA remains unclear.

Experimental Design

The mechanistic role of cross-talk between Forkhead box M1 (FOXM1) and HGF/Met signaling in promotion of PDA growth and resistance to Met inhibition was examined using cell culture, molecular biology and mouse models; and the relevance of our experimental and mechanistic findings were validated using human PDA tissues.

Results

Met was markedly overexpressed in both PDA cell lines and pancreatic tumor specimens, and the expression of Met correlated directly with that of FOXM1 in human tumor specimens. Mechanistically, FOXM1 bound to the promoter region of the Met gene and transcriptionally increased the expression of Met. Increased expression of FOXM1 enhanced the activation of HGF/Met signaling and its downstream pathways, including RAS/extracellular signal-regulated kinase 1/2, phosphoinositide 3-kinase/AKT, and signal transducer and activator of transcription 3. Furthermore, activation of HGF/Met signaling increased the expression and transcriptional activity of FOXM1, and the cross-talk between FOXM1 and HGF/Met signaling promoted PDA growth and resistance to Met inhibition.

Conclusions

Collectively, our findings identified a positive feedback loop formed by FOXM1 and HGF/Met and revealed that this loop is a potentially effective therapeutic target for PDA.