Instant diagnosis of gastroscopic biopsy via deep-learned single-shot femtosecond stimulated Raman histology.

Gastroscopic biopsy provides the only effective method for gastric cancer diagnosis, but the gold standard histopathology is time-consuming and incompatible with gastroscopy. Conventional stimulated Raman scattering (SRS) microscopy has shown promise in label-free diagnosis on human tissues, yet it requires the tuning of picosecond lasers to achieve chemical specificity at the cost of time and complexity. Here, we demonstrate that single-shot femtosecond SRS (femto-SRS) reaches the maximum speed and sensitivity with preserved chemical resolution by integrating with U-Net. Fresh gastroscopic biopsy is imaged in <60 s, revealing essential histoarchitectural hallmarks perfectly agreed with standard histopathology. Moreover, a diagnostic neural network (CNN) is constructed based on images from 279 patients that predicts gastric cancer with accuracy >96%. We further demonstrate semantic segmentation of intratumor heterogeneity and evaluation of resection margins of endoscopic submucosal dissection (ESD) tissues to simulate rapid and automated intraoperative diagnosis. Our method holds potential for synchronizing gastroscopy and histopathological diagnosis.

ß2-adrenergic receptor drives the metastasis and invasion of pancreatic ductal adenocarcinoma through activating Cdc42 signaling pathway.

Recent investigations indicate that ß2-adrenergic receptor (ß2-AR) signaling may facilitate the progression of various tumors, whose underlying mechanisms remain largely elusive. In the present study, we showed that ß2-AR recruited Cdc42 in response to isoproterenol (ISO, a ß-AR selective agonist) exposure in pancreatic ductal adenocarcinoma (PDAC) cells. The association of ß2-AR and Cdc42 promoted the activation of Cdc42, as revealed by increased levels of Cdc42-GTP, and co-incubation with ß2-AR antagonist abrogated ISO-induced activation of Cdc42. ß2-AR-mediated Cdc42 activation further led to the phosphorylation of downstream PAK1, LIMK1 and Merlin. Furthermore, we showed that the activation of ß2-AR/Cdc42 signaling facilitated the migration and invasion of PDAC cells. In addition, ß2-AR and Cdc42 were overexpressed in PDAC specimens, compared with adjacent non-tumor tissues. High expression of ß2-AR and Cdc42 were correlated with lymph node metastasis and TNM stage in PDAC patients. Finally, we showed that overexpression of ß2-AR and Cdc42 were indicative of unfavorable prognosis in PDAC patients. Taken together, our findings suggested that ß2-AR might facilitate Cdc42 signaling to drive the migration and invasion of PDAC cells, consequently resulting in the metastasis and dismal prognosis of PDAC. These studies highlight targeting ß2-AR/Cdc42 signaling as a therapeutic strategy against PDAC.

MiR-145 functions as a tumor suppressor via regulating angiopoietin-2 in pancreatic cancer cells.

BACKGROUND: Pancreatic cancer is currently one of the leading causes of cancer deaths without any effective therapies. Mir-145 has been found to be tumor-suppressive in various types of cancers. The aim of this study is to investigate the role of miR-145 in pancreatic cancer cells and explore its underlying mechanism. METHODS: Quantitative real time PCR was used to determine the expression level of miR-145 and angiopoietin-2 (Ang-2) mNRA, and the expression level of Ang-2 protein was measured by western blotting. The anti-cancer activities of miR-145 were tested both in in vitro by using cell invasion and colony formation assay and in vivo by using xenograft assay. The direct action of miR-145 on Ang-2 was predicted by TargetScan and confirmed by luciferase report assay. The vascularization of xenografts were performed by immunohistochemical analysis. RESULTS: The expression level of miR-145 was significantly lower and the expression levels of Ang-2 mRNA and protein was significantly higher in the more aggressive pancreatic cancer cells (MiaPaCa-2 and Panc-1) when compared to that in BxPC3 cells. Overexpression of miR-145 in the BxPC3, MiaPaCa-2 and Panc-1 cells suppressed the cell invasion and colony formation ability, and the expression level of Ang-2 protein in MiaPaCa-2 and Panc-1 cells was also suppressed after pre-miR-145 transfection. Intratumoral delivery of miR-145 inhibited the growth of pancreatic cancer xenografts and angiogenesis in vivo, and also suppressed the expression level of angiopoietin-2 protein. Luciferase report assay showed that Ang-2 is a direct target of miR-145, and down-regulation of angiopoietin-2 by treatment with Ang-2 siRNA in the BxPC3, MiaPaCa-2 and Panc-1 cells suppressed cell invasion and colony formation ability. The reverse transcription PCR results also showed that Tie1 and Tie2 were expressed in BxPC3, MiaPaCa-2 and Panc-1 cells. CONCLUSION: MiR-145 functions as a tumor suppressor in pancreatic cancer cells by targeting Ang-2 for translation repression and thus suppresses pancreatic cancer cell invasion and growth, which suggests that restoring of miR-145 may be a potential therapeutic target for pancreatic cancer.

In vitro and in vivo evaluation of stimuli-responsive vesicle from PEGylated hyperbranched PAMAM-doxorubicin conjugate for gastric cancer therapy.

Gastric Cancer is one of the major leading causes of death by cancer worldwide, but the chemotherapeutics, one of the preferred approaches, bring about extensive side effects when systemically injected. In our work, doxorubicin-loaded pH and redox responsive hyperbranched poly(amidoamine)(h-PAMAM)-based vesicle was prepared to enhance anti-tumor efficacy of chemotherapeutic compounds. The doxorubicin (DOX) molecules were attached to PEGylated h-PAMAM by acid sensitive cis-aconityl linkage to form pH sensitive conjugate (PPCD), which self-assembled in THF into micelles. The resulted micelles were then crosslinked by disulfide bonds and transferred from THF into water to form vesicles, which could be disassembled into small-sized conjugates under the redox condition. The drug release profiles showed that the PPCD vesicle presented stimuli-triggered drug release in acidic and reducing environment, and lower DOX leakage under neutral condition. The in vitro cell assay reflected the rapid DOX release and significant tumor-cytotoxic effect of the PPCD vesicle. The in vivo anticancer activity and systematic toxicity studies showed that the PPCD vesicles had lower tissue toxicity with good antitumor effect. In brief, h-PAMAM-based PPCD vesicle provides a safe and effective drug delivery system for the therapy of gastric cancer.

[The expression of peripheral Th1 and Th17 cells in inflammatory bowel disease and its potential clinical value].

OBJECTIVE: To explore the probable role of Th1 and Th17 cells in the pathogenesis of inflammatory bowel disease (IBD). METHODS: The peripheral blood mononuclear cells (PBMCs) from peripheral blood specimens were collected in the study, including 40 healthy controls, 42 ulcerative colitis (UC) and 39 Crohn's disease (CD). The proportion of Th1 and Th17 cells in the PBMCs was detected with flow cytometry after stimulated by PMA and ionomycin. The result and the clinical data were analyzed. RESULT: The Th1 cell expression was increased in CD (38.32 ± 16.18)% and UC group (34.23 ± 11.60)%, compared with the controls (24.58 ± 10.02)% (P < 0.01). During the convalescence, the Th1 expression in the CD and UC groups in vivo was significantly reduced without difference between the two groups (P > 0.05) . In the IBD group , significant difference in the frequency of Th17 cells could be found between the CD group (2.51 ± 1.59)% and the UC group (4.15 ± 2.75)%, while the Th17 cells were increased in both groups, compared with the controls (1.44 ± 0.73)% (P < 0.05) . Obvious difference in the frequency of Th17 cells could be found between patients at different activity stages and remission stages. The proportion of Th17 cells were higher in the UC patients than that in the CD patients (P < 0.01) . The Th17/Th1 ratio of CD patients, UC patients were 0.08 ± 0.06, 0.14 ± 0.11, which were both higher that in the controls (0.07 ± 0.06). Significant difference could be found between the UC group and the CD group (P < 0.01). CONCLUSIONS: The higher proportion of Th1 and Th17 cells are detected in the peripheral blood of IBD patients, which is correlated closely to the activity of the disease. Th1 and Th17 cells may play an important role in the pathogenesis of IBD.

Poly(vinylcaprolactam)-based biodegradable multiresponsive microgels for drug delivery.

Poly(vinylcaprolactam) (PVCL)-based biodegradable microgels were prepared for the biomedical application as drug delivery system via precipitation polymerization, where N,N-bis(acryloyl) cystamine (BAC) served as cross-linker, methacrylic acid (MAA) and polyethylene glycol (PEG) methyl ether methacrylate acted as comonomers. The microgels with excellent stability had distinct temperature sensitivity as largely observed in the case of PVCL-based particles and their volume phase transition temperature (VPTT) shifted to higher temperature with increasing MAA content and ambient pH. In the presence of reducing agent glutathione (GSH) or dithiothreitol (DTT), the microgels could be degraded into individual linear polymer chains by the cleavage of the disulfide linkages coming from the cross-linker BAC. The microgels could effectively encapsulate Doxorubicin (DOX) inside and presented stimuli-triggered drug release in acidic or reducing environment. The results of the cytotoxicity assays further demonstrated that the blank microgels were nontoxic to normal cells while DOX-loaded microgels presented efficient antitumor activity to HeLa cells.