A research of STEAP1 regulated gastric cancer cell proliferation, migration and invasion in vitro and in vivos.

Six-Transmembrane Epithelial Antigene of the Prostate 1 (STEAP1) is associated with the occurrence and development of cancer. This study aimed to clarify the role of STEAP1 in gastric cancer tumour growth and metastasis, as well as its molecular mechanism of action.Statistical methods were used for clinical data analysis. Protein expression was detected using immunohistochemistry(IHC). The mRNA and protein expression in the cell cultures were detected using reverse transcription-polymerase chain reaction(RT-PCR) and western blot analysis. Overexpression and silencing models were constructed using plasmid and lentivirus transfection. To detect cell proliferation in vitro, Cell Counting Kit-8(CCK-8), flow cytometry and colony formation assays were used; transwell and wound healing assays were used to detect cell migration and invasion;For in vivo experiments, nude BALB/c mice were used for detecting subcutaneous tumorigenesis and intraperitoneal implantation. In the results,we found STEAP1 was overexpressed in gastric cancer tissues and cell lines. Single-factor and Cox analyses showed that STEAP1 gene expression level correlated with poor prognosis. Up-regulation of STEAP1 increased cell proliferation, migration and invasion, which decreased after STEAP1 was knocked down. These changes were achieved via the activation of the AKT/FoxO1 pathway and epithelial-mesenchymal transformation (EMT). The in vivo animal experiments showed that STEAP1 knock down, resulted in a decrease in the subcutaneous tumour and peritoneal tumour formation.

Therapeutic value of lymph node dissection for Siewert type II and III adenocarcinoma: meta-analysis.

BACKGROUND: Adenocarcinoma of the oesophagogastric junction presents an increasing incidence. Surgical resection with lymphadenectomy is the only curative treatment modality at the present time, but the optimal extent of lymphadenectomy is debatable. The aim of the present meta-analysis was to estimate the therapeutic value of each nodal station. METHODS: Studies reporting the therapeutic value index of each nodal station in Siewert types II/III oesophagogastric junction (EGJ) were searched in PubMed, Web of Science and Embase up to October 2022. This index was calculated by multiplication of metastatic incidence and 5-year overall survival rate at each nodal station. Risk of bias was assessed using the Joanna Briggs Institute Critical Appraisal Checklist for Prevalence Studies. Pooled metastatic incidence and therapeutic value index were calculated using RevMan 5.4. RESULTS: Twelve studies involving 3513 patients were included. Nodes No. 3, 1, 7 and 2 were routinely dissected and achieved a high (≥10) or moderate (5-10) therapeutic value index in decreasing order, due to their high metastatic incidence and favourable survival rate. The index was relatively low (2-5) in suprapancreatic nodes No. 9, 11p and 8a. The index for nodes No. 4d and 10 was relatively low in Siewert type Ⅲ EGJ but very low (<2) in type Ⅱ. The index was very low for nodes No. 5, 6, 11d and 12a, due to their low metastatic incidence and poor survival if positive. Para-aortic, parahiatal and mediastinal nodes were dissected only in highly selected cases. Dissection of the lower mediastinal nodes, especially No. 110, could improve survival rates in type Ⅱ EGJ. CONCLUSION: These data could help assess the optimal extent of lymphadenectomy for EGJ. Nodes No. 1, 2, 3, 7, 8a, 9 and 11p need routine dissection in both Siewert types Ⅱ/Ⅲ EGJ; nodes around the lower oesophagus (especially No. 110) in Siewert type Ⅱ EGJ and nodes No. 4d and 10 in Siewert type Ⅲ EGJ might be considered for dissection.

Mechanistic aspects of photo-induced formation of peroxide ions on the surface of cubic Ln2O3 (Ln = Nd, Sm, Gd) under oxygen.

The photo-induced formation of peroxide ions on the surface of cubic Ln2O3 (Ln = Nd, Sm, Gd) was studied by in situ microprobe Raman spectroscopy using a 325 nm laser as excitation source. It was found that the Raman bands of peroxide ions at 833-843 cm(-1) began to grow at the expense of the Ln(3+)-O(2-) bands at 333-359 cm(-1) when the Ln2O3 samples under O2 were continuously irradiated with a focused 325 nm laser beam at temperatures between 25-150 °C. The intensity of the peroxide Raman band was found to increase with increasing O2 partial pressure, whereas no peroxide band was detected on the Ln2O3 under N2 as well as on the samples first irradiated with laser under Ar or N2 followed by exposure to O2 in the dark. The experiments using (18)O as a tracer further confirmed that the peroxide ions are generated by a photo-induced reaction between O2 and the lattice oxygen (O(2-)) species in Ln2O3. Under the excitation of 325 nm UV light, the transformation of O2 to peroxide ions on the surface of the above lanthanide sesquioxides can even take place at room temperature. Basicity of the lattice oxygen species on Ln2O3 also has an impact on the peroxide formation. Higher temperature or laser irradiation power is required to initiate the reaction between O2 and O(2-) species of weaker basicity.

[XPS and Raman studies of diamond-like carbon films prepared by various deposition techniques].

Diamond-like carbon (DLC) films were deposited on a silicon chip substrate by a metal pulsed magnetic filtered cathodic vacuum arc deposition technique, a direct current magnetron sputtering technique and a pulsed glow discharge plasma enhanced chemical vapor deposition technique. And the characteristics of DLC films were investigated using laser Raman spectroscopy and X-ray photoelectron spectroscopy. The spectra of diamond like carbon were collected using Raman spectrometers with 325 nm flters. It was found that DLC films prepared by various deposition technique have different G-peak, D-peak, T-peak, the full width at half maximum(FWHM)of G-peak, D-peak and T-peak, the intensity ratio I(D)/I(G) and I(T)/I(G) and the sp3 content. Among them, the films grown by metal pulsed magnetic filtered cathodic vacuum arc deposition technique have the largest G-peak wave number and the intensity ratio I(T)/I(G), the minimum of the intensity ratio I(D)/I(G), G-FWHM and the maximum sp3 content; those grown by the direct current magnetron sputtering technique have the 2nd largest G-peak wave number, the intensity ratio I(D)/I(G) and I(T)/I(G) and sp3 content, however, they have the largest G-FWHM, while those grown by the pulsed glow discharge plasma enhanced chemical vapor deposition technique have the minimum G-peak wave number and the intensity ratio I(T)/I(G) and sp3 content, and the maximum intensity ratio I(D)/I(G).

LINC01235-TWIST2 feedback loop facilitates epithelial-mesenchymal transition in gastric cancer by inhibiting THBS2.

Although the anomalous expression of long non-coding RNAs (lncRNAs) has been extensively investigated in numerous carcinomas including gastric cancer (GC), their function remains unclear. The aim of our study was to explore the role of LINC01235 in GC. We used real-time quantitative PCR (RT-qPCR) to measure the expression of LINC01235 and twist family bHLH transcription factor 2 (TWIST2) in GC tissues. Scratch and transwell assays were performed to evaluate cellular capacity for migration and invasion. Gene relationships were explored by Weighted Gene Co-Expression Network Analysis (WGCNA). We measured TWIST2, thrombospondin 2 (THBS2) and epithelial-mesenchymal transition (EMT)-related proteins with western blot. We also used Pearson correlation analysis and the Kaplan-Meier method to detect associations among genes and overall survival. We found that LINC01235 was upregulated in GC tissues and cells. LINC01235 down-regulation restricted migration and invasion. Interestingly, we found the LINC01235-TWIST2-THBS2 axis induced EMT. Additionally, TWIST2 upregulated LINC01235 transcription in luciferase and chromatin immunoprecipitation (ChIP) assays. Bioinformatics analysis showed that microRNA (miR)-6852-5p might be a key gene involved in the regulation of TWIST2 by LINC01235. The LINC01235-TWIST2 positive feedback loop mainly affected migration and invasion of GC cells, which suggests it may serve as a potential therapeutic target in gastric cancer.

Photoinduced Formation of Peroxide Ions on La2O3 and Nd2O3 under O2: Effects of Excitation Wavelength and Crystal Structure.

Photoinduced formation of peroxide ions on La2O3 and Nd2O3 under O2 was studied by in-situ microprobe Raman spectroscopy with attention focused on the effect of excitation wavelength and crystal structure on the O2(2-) formation. It was found that photoexcitations at 633, 532, 514, and 325 nm can induce O2(2-) formation over La2O3 at 450 °C. By contrast, photoexcitation at 785 nm does not cause formation of O2(2-) up to 500 °C. Photoexcitation at 325 nm can induce O2(2-) formation on cubic Nd2O3 at 25 °C, but cannot induce O2(2-) formation on hexagonal Nd2O3 up to 200 °C. The significant difference in the behavior of O2(2-) formation over the Nd2O3 samples of the two structures can be related to the difference in the capacity to adsorb O2. Since the number of oxygen vacancies in cubic Nd2O3 is larger than that in the hexagonal one, the former has a higher capacity than the latter to adsorb O2. As a result, cubic Nd2O3 is more favorable to the reaction of O2 with O(2-) to generate O2(2-). The structural similarity between cubic Nd2O3 and Nd2O2(O2) may be another factor in favor of peroxide formation.

Separation of phytic acid and other related inositol phosphates by high-performance ion chromatography and its applications.

A high-performance anion-exchange chromatographic method was developed for the separation of phytic acid and other inositol phosphates (myo-inositol bis-, tris-, tetrakis-, and pentakisphosphates) with gradient elution and ultraviolet absorbance detection after post-column derivatization. With the acidic eluents, the combination of anion-exchange and ion suppression retention mechanisms led to the separation of 35 inositol phosphates (excluding enantiomers) into 27 peaks for the first time, and the retention behaviors of all myo-inositol bis- to hexakisphosphate isomers were studied. The whole separation procedure was completed within 65 min. Based on the investigations of nonenzymatic hydrolysis of phytic acid under different conditions by using this method, an in-house reference standard solution was produced, which can be used for method development. In addition, by applying this method to in vitro kinetic studies, at least one new enzymatic hydrolysis pathway of phytic acid was found, and one rule of enzymatic dephosphorylation of inositol phosphates (position effect) was proposed and another one (neighboring effect) was confirmed. The principle of the proposed identification approach for several inositol phosphate isomers based on hydrolysis products study will be applicable to other natural products analysis, for which standards are very expensive or not available.