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Synopsis: Laparoscopy combined with retrieval bag is an effective method for disseminated peritoneal leiomyomatosis that can prevent the spreading of tumor fragments. [ABSTRACT FROM AUTHOR]

Based on the magnetohydrodynamics model, this study numerically investigated the influence of a transverse non-uniform magnetic field on the flow and heat transfer characteristics of molten salt in a conductive pipe. The magnetic field was constructed with three sections including gradient and uniform regions, which was fitting to real application of the magnetic field. The flow and heat transfer of molten salt were studied within the ranges of 0 ≤ Ha ≤ 200 and 3000 ≤ Re ≤ 12 000. The results indicated that variation of magnetic field had significant effects on the flow velocity, turbulent intensity, and Joule heat, thus influencing the temperature and the Nusselt number of molten salt. Although the flow in core region was suppressed by the magnetic field, the flow velocity was enhanced and turbulence was reduced near the pipe wall, which was shown obviously different within three regions of the magnetic field. An interesting phenomenon of local heat transfer enhancement with increasing magnetic intensity was observed in the first section of the magnetic field, which was from the complex effects of flow velocity and turbulence. In addition, the Joule heat was calculated and analyzed to determine its influence on heat transfer under the magnetic field. A detailed analyzation of magnetic fluid flow in this study was provided to hopefully promote the molten salt in real application of flow and heat transfer. [ABSTRACT FROM AUTHOR]

Non‐small cell lung cancer (NSCLC) with wild‐type epidermal growth factor receptor (EGFR) is intrinsic resistance to EGFR‐tyrosine kinase inhibitors (TKIs), such as afatinib. Celastrol, a natural compound with antitumor activity, was reported to induce paraptosis in cancer cells. In this study, intrinsic EGFR‐TKI‐resistant NSCLC cell lines H23 (EGFR wild‐type and KRAS mutation) and H292 (EGFR wild‐type and overexpression) were used to test whether celastrol could overcome primary afatinib resistance through paraptosis induction. The synergistic effect of celastrol and afatinib on survival inhibition of the NSCLC cells was evaluated by CCK‐8 assay and isobologram analysis. The paraptosis and its modulation were assessed by light and electron microscopy, Western blot analysis, and immunofluorescence. Xenografts models were established to investigate the inhibitory effect of celastrol plus afatinib on the growth of the NSCLC tumors in vivo. Results showed that celastrol acted synergistically with afatinib to suppress the survival of H23 and H292 cells by inducing paraptosis characterized by extensive cytoplasmic vacuolation. This process was independent of apoptosis and not associated with autophagy induction. Afatinib plus celastrol‐induced cytoplasmic vacuolation was preceded by endoplasmic reticulum stress and unfolded protein response. Accumulation of intracellular reactive oxygen species and mitochondrial Ca2+ overload may be initiating factors of celastrol/afatinib‐induced paraptosis and subsequent cell death. Furthermore, Celastrol and afatinib synergistically suppressed the growth of H23 cell xenograft tumors in vivo. The data indicate that a combination of afatinib and celastrol may be a promising therapeutic strategy to surmount intrinsic afatinib resistance in NSCLC cells. [ABSTRACT FROM AUTHOR]

Background: To explore the association between serum human epidermal growth factor receptor 2 (HER 2) extracellular domain (ECD) levels and tissue HER 2 status in metastatic gastric cancer. Patients and Methods: HER 2 status was retrospectively analyzed in 219 advanced gastric or gastroesophageal junction (GEJ) patients. Serum HER 2 ECD was measured by chemiluminescent assay and tissue HER 2 was assessed by fluorescent in situ hybridisation (FISH) and immunohistochemistry (IHC) assay. Results: Significant associations were found between serum HER 2 ECD levels and tissue HER 2 status. Twenty-four patients had HER 2 ECD levels >16.35 ng/mL, which has a sensitivity of 51.4% and a specificity of 97.3% to predict tissue HER 2 status. When the cut-off value was increased to 22 ng/mL, then all 12 patients with serum HER 2 ECD levels>22 ng/mL were tissue HER 2 positive, corresponding to a specificity of 100% and a sensitivity of 32.4%. High serum HER 2 ECD levels were strongly associated with the intestinal histological type (Lauren’s classification), liver metastasis, multiple metastasis (>2) and increased LDH levels, but not with overall survival. Conclusions: The high specificity of the serum HER 2 ECD assay in predicting tissue HER 2 status suggests its potential as a surrogate marker of the HER 2 status in gastric cancer. [ABSTRACT FROM AUTHOR]

The layered Li2MnO3 is investigated by using the first-principles calculations within the GGA and GGA+U scheme, respectively. Within the GGA+U approach, the calculated intercalation voltage (ranges from 4.5 V to 4.9 V) is found to be in good agreement with experiments. From the analysis of electronic structure, the pure phase Li2MnO3 is insulating, which is indicative of poor electronic-conduction properties. However, further studies of lithium ion diffusion in bulk Li2MnO3 show that unlike the two-dimensional diffusion pathways in rock salt structure layered cathode materials, lithium can diffuse in a three-dimensional pathway in Li2MnO3, with moderate lithium migration energy barrier ranges from 0.57 to 0.63 eV. [ABSTRACT FROM AUTHOR]

Thermochomic VO 2 thin films are fabricated by using high power impulse magnetron sputtering at room temperature. In order to increase the crystallinity and transparency of VO 2 thin films, first a buffer layer of TiO 2 is deposited on the glass substrate. Then TiO 2 /VO 2 stacks are post-annealed at a temperature of 500 °C for 3 min. The transmittance as functions of film thickness and O 2 /Ar ratio during film deposition is discussed. It is found that the O/V atomic ratio decreases with increasing O 2 /Ar ratio, which is due to serious inter-diffusion inside stacked layers. At high O 2 /Ar ratio, columnar-shaped crystals are suggested, which belongs to V 2 Ti 3 O 9 :Si quaternary oxide. The depth profiles of binding energies measured by X-ray photoelectron spectroscopy are compared with different O 2 /Ar ratios. Good endurance property for a thermal stress cycle of 25 °C/85 °C is obtained under the O 2 /Ar ratio of 6%. The laminated film shows satisfactory optical properties with an excellent solar regulation efficiency (Δ T sol = 10.4%) and an applicable luminous transmittance (T lum = 35.2%) in a low-temperature state. • VO 2 films are fabricated by HIPIMS and annealed with a low thermal budget. • Films show good solar regulation efficiency and applicable luminous transmittance. • Good endurance properties are obtained. [ABSTRACT FROM AUTHOR]

Neural tube defects (NTDs) are severe congenital neurodevelopmental disorders arising from incomplete neural tube closure. Although folate supplementation has been shown to mitigate the incidence of NTDs, some cases, often attributable to genetic factors, remain unpreventable. The SHROOM3 gene has been implicated in NTD cases that are unresponsive to folate supplementation; at present, however, the underlying mechanism remains unclear. Neural tube morphogenesis is a complex process involving the folding of the planar epithelium of the neural plate. To determine the role of SHROOM3 in early developmental morphogenesis, we established a neuroepithelial organoid culture system derived from cynomolgus monkeys to closely mimic the in vivo neural plate phase. Loss of SHROOM3 resulted in shorter neuroepithelial cells and smaller nuclei. These morphological changes were attributed to the insufficient recruitment of cytoskeletal proteins, namely fibrous actin (F-actin), myosin II, and phospho-myosin light chain (PMLC), to the apical side of the neuroepithelial cells. Notably, these defects were not rescued by folate supplementation. RNA sequencing revealed that differentially expressed genes were enriched in biological processes associated with cellular and organ morphogenesis. In summary, we established an authentic in vitro system to study NTDs and identified a novel mechanism for NTDs that are unresponsive to folate supplementation.

Ovarian cancer (OC) is the most lethal gynecological cancer in women. Studies had reported that immune-related lncRNAs signatures were valuable in predicting the survival and prognosis of patients with various cancers. In our study, the prognostic value of immune-related lncRNAs was investigated in OC patients from TCGA-RNA-seq cohort (n=378) and HG-U133_Plus_2 cohort (n=590), respectively. Pearson correlation analysis was implemented to screen the immune-related lncRNA and then univariate Cox regression analysis was performed to explore their prognostic value in OC patients. Five prognostic immune-related lncRNAs were identified as prognostic lncRNAs. Besides, they were inputted into a LASSO Cox regression to establish and validate an immune-related lncRNA prognostic signature in TCGA-RNA-Seq cohort and HG-U133_Plus_2 cohort, respectively. Based on the best cut-off value of risk score, patients were divided into high- and low-risk groups. Survival analysis suggested that patients in the high-risk group had a worse overall survival (OS) than those in the low-risk group in both cohorts. The association between clinicopathological feathers and risk score was then evaluated by using stratification analysis. Moreover, we constructed a nomogram based on risk score, age and stage, which had a strong ability to forecast the OS of the OC patients. The influence of risk score on immune infiltration and immunotherapy response were assessed and the results suggested that patients with high-risk score might recruit multiple immune cells and stromal cells, leading to facilitating immune surveillance evasive. Ultimately, we demonstrated that the risk model was associated with chemotherapy response of multiple antitumor drugs, especially for paclitaxel, metformin and veliparib, which are commonly used in treating OC patients. In conclusion, we constructed a novel immune-related lncRNA signature, which had a potential prognostic value for OC patients and might facilitate personalized counselling for immunotherapy and chemotherapy., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Li, Liu, Chen, Zhang, Wu and Wang.)

Cancer currently ranks among the leading causes of death globally. Cancer invasion and metastasis transform locally grown cancers to a systemic and life-threatening disease, which accounts for the most significant challenge in cancer treatment. Recent studies showed that Metformin, the most commonly used first-line oral drug for the treatment of type 2 diabetes (T2DM), could prevent and treat various cancers. Moreover, multiple evidence suggested that metformin inhibited cancer invasion and metastasis, which could improve the prognosis of cancer patients administrated with metformin. To better understand the anti-cancer role of metformin, the present review summarized the potential mechanisms of inhibiting cancer invasion and metastasis by metformin, including AMPK signaling pathway, EMT signaling pathway, epigenetic modification and so on. However, multiple problems remain unresolved and more clinical trials are needed to prove the inhibition of cancer invasion and metastasis by metformin., Competing Interests: None., (AJTR Copyright © 2020.)

Previous studies have revealed faster detection of snake images in humans and non-human primates (NHPs), suggesting automatic detection of evolutionary fear-relevant stimuli. Furthermore, human studies have indicated that general fear-relevance rather than evolutionary relevance is more effective at capturing attention. However, the issue remains unclarified in NHPs. Thus, in the present study, we explored the attentional features of laboratory-reared monkeys to evolutionary and general fear-relevant stimuli (e.g., images of snakes, capturing gloves). Eye-tracking technology was utilized to assess attentional features as it can provide more accurate latency and variables of viewing duration and frequency compared with visual search task (VST) and response latency adopted in previous studies. In addition, those with autism spectrum disorder (ASD) show abnormal attention to threatening stimuli, including snake images. Rett syndrome (RTT) is considered a subcategory of ASD due to the display of autistic features. However, the attentional features of RTT patients or animal models to such stimuli remain unclear. Therefore, we also investigated the issue in MECP2 gene-edited RTT monkeys. The influence of different cognitive loads on attention was further explored by presenting one, two, or four images to increase stimulus complexity. The eye-tracking results revealed no significant differences between RTT and control monkeys, who all presented increased viewing (duration and frequency) of snake images but not of aversive stimuli compared with control images, thus suggesting attentional preference for evolutionary rather than general fear-relevant visual stimuli. Moreover, the preference was only revealed in visual tasks composed of two or four images, suggesting its cognitive-load dependency.

Cisplatin exert its anticancer effect by creating intrastrand and interstrand DNA cross-links which block DNA replication and is a major drug used to treat lung cancer. However, the main obstacle of the efficacy of treatment is drug resistance. Here, we show that expression of translesion synthesis (TLS) polymerase Q (POLQ) was significantly elevated by exposure of lung cancer cells A549/DR (a cisplatin-resistant A549 cell line) to cisplatin. POLQ expression correlated inversely with homologous recombination (HR) activity. Co-depletion of BRCA2 and POLQ by siRNA markedly increased sensitivity of A549/DR cells to cisplatin, which was accompanied with impairment of double strand breaks (DSBs) repair reflected by prominent cell cycle checkpoint response, increased chromosomal aberrations and persistent colocalization of p-ATM and 53BP1 foci induced by cisplatin. Thus, co-knockdown of POLQ and HR can efficiently synergize with cisplatin to inhibit A549/DR cell survival by inhibiting DNA DSBs repair. Similar results were observed in A549/DR cells co-depleted of BRCA2 and POLQ following BMN673 (a PARP inhibitor) treatment. Importantly, the sensitization effects to cisplatin and BMN673 in A549/DR cells by co-depleting BRCA2 and POLQ was stronger than those by co-depleting BRCA2 and other TLS factors including POLH, REV3, or REV1. Our results indicate that there is a synthetic lethal relationship between pol θ-mediated DNA repair and HR pathways. Pol θ may be considered as a novel target for lung cancer therapy.

Background: Cisplatin is one of the most commonly used chemotherapy agent for lung cancer. The therapeutic efficacy of cisplatin is limited by the development of resistance. In this study, we test the effect of RNA interference (RNAi) targeting Fanconi anemia (FA)/BRCA pathway upstream genes on the sensitivity of cisplatin-sensitive (A549 and SK-MES-1) and -resistant (A549/DDP) lung cancer cells to cisplatin., Result: Using small interfering RNA (siRNA), knockdown of FANCF, FANCL, or FANCD2 inhibited function of the FA/BRCA pathway in A549, A549/DDP and SK-MES-1 cells, and potentiated sensitivity of the three cells to cisplatin. The extent of proliferation inhibition induced by cisplatin after knockdown of FANCF and/or FANCL in A549/DDP cells was significantly greater than in A549 and SK-MES-1 cells, suggesting that depletion of FANCF and/or FANCL can reverse resistance of cisplatin-resistant lung cancer cells to cisplatin. Furthermore, knockdown of FANCL resulted in higher cisplatin sensitivity and dramatically elevated apoptosis rates compared with knockdown of FANCF in A549/DDP cells, indicating that FANCL play an important role in the repair of cisplatin-induced DNA damage., Conclusion: Knockdown of FANCF, FANCL, or FANCD2 by RNAi could synergize the effect of cisplatin on suppressing cell proliferation in cisplatin-resistant lung cancer cells through inhibition of FA/BRCA pathway.

IQ-domain GTPase-activating proteins (IQGAPs) are evolutionary conserved multidomain proteins that are found in numerous organisms, from yeast to mammals. To date, three IQGAP proteins have been identified in humans, of which IQGAP1 is the best characterized. As a scaffold protein, IQGAP1 contains multiple protein-interacting domains, which modulate binding to target proteins. Recent mounting studies demonstrated a role for IQGAP1 in tumor progression, supported by the altered expression and subcellular distribution of IQGAP1 in tumors. The contribution of IQGAP1 to tumor progression appears to involve a complex interplay of cell functions by integrating diverse signal transduction pathways and coordinating activities, such as cell adhesion, migration, invasion, proliferation and angiogenesis.

Previous data have shown that the type II cGMP‑dependent protein kinase (PKG II) inhibits the EGF‑induced MAPK signaling pathway. In order to thoroughly investigate PKG, it is necessary to elucidate the function of another type of PKG, PKG I. The aim of this study was to investigate the possible inhibitory effect of PKG II and PKG I activity on the basic fibroblast growth factor (bFGF)‑induced proliferation and migration of U251 human glioma cells and the possible underlying mechanisms. U251 cells were infected with adenoviral constructs encoding cDNA of PKG I (Ad‑PKG I) or PKG II (Ad‑PKG II) to increase the expression levels of PKG I or PKG II and then treated with 8‑Br‑cGMP and 8‑pCPT‑cGMP, respectively, to activate the enzyme. An MTT assay was used to detect the proliferation of the U251 cells. The migration of the U251 cells was analyzed using a Transwell migration assay. Western blot analysis was used to detect the phosphorylation/activation of the fibroblast growth factor receptor (FGFR), MEK and ERK and the nuclear distribution of p-ERK. The results showed that bFGF treatment increased the proliferation and migration of U251 cells, accompanied by increased phosphorylation of FGFR, MEK and ERK. Furthermore, the nuclear distribution of p-ERK increased following bFGF treatment. Increasing the activity of PKG II through infection with Ad-PKG II and stimulation with 8-pCPT-cGMP significantly attenuated the aforementioned effects of the bFGF treatment, while increased PKG I activity did not inhibit the effects of bFGF treatment. These data suggest that increased PKG II activity attenuates bFGF‑induced proliferation and migration by inhibiting the MAPK/ERK signaling pathway, whereas PKG I does not.

In our previous study, we demonstrated that type II cGMP-dependent protein kinase (PKG II) was expressed at lower levels in different human cancer cell lines and that exogenous PKG II inhibited epidermal growth factor (EGF)-induced MAPK/ERK signaling. In order to investigate its functions further in this signaling pathway, it is necessary to elucidate whether endogenous PKG has the same effect or not. This study aimed to investigate the possible inhibitory effect of endogenous PKG activity on EGF-induced MAPK/ERK signal transduction in human lung cancer cells and its mechanism. Human small cell lung carcinoma cells (SCLCs) were treated with the PKG-selective cGMP analog 8-pCPT-cGMP to activate endogenous PKG, EGF and cGMP followed by EGF, respectively. The results showed that increased endogenous PKG activity inhibited the EGF-induced phosphorylation of the epidermal growth factor receptor (EGFR) and the binding between Sos1 and Grb2. In addition, EGF-triggered Ras activation was reversed by increased endogenous PKG activity. While the EGF-induced phosphorylation of MEK and ERK were inhibited by increased endogenous PKG activity, there was a significant increase of phosphorylated vasodilator-stimulated phosphoprotein (p-VASP) at Ser239. Furthermore, we investigated whether endogenous PKG exerted its effects on EGF-induced MAPK/ERK signaling through phosphorylation of VASP at Ser239. Downregulation of the levels of p-VASP Ser239 by point mutation blocked the effects of endogenous PKG on EGF-induced MAPK/ERK signal transduction. The data shown here suggest that endogenous PKG reverses the EGF-induced MAPK/ERK signaling pathway by phosphorylating VASP at Ser239.

RhoA, an extensively studied member of the Rho GTPase family, has been identified as a mediator of pro-inflammatory responses and aggressive carcinogenesis. Bacterial lipopolysaccharide (LPS) is known to be a potent stimulator of inflammatory cytokine production. LPS is able to alter the activity of RhoA and the subcellular distribution of RhoA is altered according to its activity. In this study, we investigated a possible link between RhoA and the LPS/nuclear factor (NF)-κB signaling pathway. In the present study, western blotting and pull-down and immunofluorescence assays were performed to investigate the activity of RhoA in A549 cells following LPS stimulation. The results showed that LPS was able to activate RhoA. Furthermore, western blotting and an immunofluorescence assay were carried out to investigate the nuclear expression of RhoA in A549 cells following LPS stimulation. The results indicated that LPS triggers the nuclear translocation of RhoA. Furthermore, western blotting, NF-κB small interfering RNA (siRNA) transfection and an immunofluorescence assay were performed to investigate the role of NF-κB in LPS-induced RhoA nuclear translocation in A549 cells. The results showed that LPS-induced RhoA nuclear translocation was inhibited by NF-κB depletion in A549 cells. RhoA and NF-κB siRNA transfection, western blotting and ELISA were carried out to investigate the role of RhoA in the LPS-induced secretion of interleukin (IL)-6 and IL-8 in A549 cells. The depletion of RhoA using RhoA siRNA decreased the LPS-induced secretion of IL-6 and IL-8, similar to the effect of NF-κB depletion. These results demonstrate that LPS is able to activate RhoA and trigger its nuclear translocation, which is dependent on NF-κB, and that RhoA plays a significant role in the LPS/NF-κB signaling pathway.

Purpose: Small bowel adenocarcinoma (SBA) is a rare malignancy, and most patients present with unresectable or metastatic disease. Thus far, no standard chemotherapeutic regimen has been established and related data are scarce, especially in Eastern countries. The purpose of this multicenter study was to evaluate the efficacy and toxicity of oxaliplatin combined with fluoropyrimidines in Chinese patients with advanced SBA., Methods: Advanced SBA patients who received FOLFOX (5-fluorouracil/5-FU plus leucovorin and oxaliplatin)/ CAPOX (capecitabine plus oxaliplatin) as first-line chemotherapy between February, 2004 and October, 2010 were identified from 3 large medical centers in China. The response rate (RR), progression-free survival (PFS), overall survival (OS), and chemotherapy-associated toxicity were evaluated. Cox models were applied for multivariate analyses., Results: Of 34 patients, with SBA 28 received FOLFOX and 6 CAPOX. The objective response (OR) and disease control (DC) rates were 32.3% and 61.7%, respectively. The median PFS and OS were 6.3 and 14.2 months, respectively. The toxicity was tolerable, grade 3-4 toxicity was rare. In multivariate analysis, only multi-organ metastasis reached borderline significance for shorter PFS (p=0.059), but the variables of age (>65 years; p=0.001), and multi-organ metastasis (p=0.001) were significantly associated with poor OS., Conclusion: To our knowledge, this multicenter retrospective study is the first and largest one among Asian studies at present estimating oxaliplatin combined with fluoropyrimidines as first-line chemotherapy for advanced SBA. FOLFOX/CAPOX is proved effective for advanced SBA in this study, but the results do not absolutely agree with previous studies from Western countries, showing that further studies are still needed.

The scaffold protein IQGAP1 is closely related to certain Rho GTPases. Research has revealed that IQGAP1 acts as an effector of Cdc42 and Rac1 in the regulation of cell activity such as proliferation and migration. However, whether IQGAP1 is associated with RhoC, another important Rho GTPase, is unclear. Previous results from our laboratory indicated that IQGAP1 and RhoC are highly expressed in gastric cancer tissues and cells. This study was designed to investigate the possible interaction between IQGAP1 and RhoC in the regulation of the migration of cancer cells. The expression of IQGAP1 and RhoC in gastric cancer tissues and cell lines was detected by Western blotting. siRNAs targeting IQGAP1 or RhoC were transfected into gastric cancer cells to knock down the expression of the proteins. Adenoviral constructs encoding full length IQGAP1, the C‑terminal fragment of IQGAP1, and the constitutively active RhoC gene were used to infect gastric cancer cells to increase the expression of the proteins. The migratory activity of a gastric cancer cell line was measured by a transwell migration assay. Western blotting revealed that the IQGAP1 and RhoC proteins were highly expressed in gastric cancer tissues and cells. Spearman's rank correlation analysis indicated that the increases in the expression of IQGAP1 and RhoC were closely correlated. The transwell migration assay revealed that both IQGAP1 and RhoC stimulated the migration activity of the gastric cancer cell line AGS. The knockdown of IQGAP1 expression by siRNA blocked the migration‑stimulating activity of RhoC, while the knockdown of RhoC expression had no effect on the migration-stimulatory activity of IQGAP1. Co-IP results showed that RhoC and IQGAP1 bound to each other. These results reveal a previously unrecognized interaction between IQGAP1 and RhoC, and demonstrate that IQGAP1 is a downstream effector of RhoC in the regulation of the migration activity of gastric cancer cells.

Vasodilator stimulated phosphoprotein (VASP) is known as an actin-binding protein. The phosphorylation of VASP plays an important role in its function. In a previous study, serine 157 phosphorylated VASP (p-VASP S157) was shown to be co-localized with α-tubulin on the spindle of SGC-7901 cells. In the present study, we demonstrated that the level of p-VASP S157 increases and has a peak which coincides with serine 10 phosphorylated histone 3 (p-H3 S10) during mitotic progression in a human cervical cancer cell line (HeLa cells). Application of protein kinase A inhibitor H89, protein kinase G inhibitor KT5823 and protein kinase C inhibitor Go6983, or a combination of these inhibitors, caused a partial decrease in p-VASP S157 and a delay in G2/M progression. Depletion of p-VASP S157 by VASP siRNA resulted in an increase in binucleated cells and x4n cells, a further delay in G2/M progression and the inhibition of HeLa cell proliferation. These results suggest that p-VASP S157 may play an important role in the G2/M transition and the completion of cytokinesis in HeLa cells.

Our previous studies have demonstrated that the expression and activity of protein kinase G (PKG) II are significantly lower in human gastric cancer cell lines than in normal cells. This study was designed to investigate the effect of PKG II activation on the proliferation of human cultured BGC-823 gastric cancer cells. An adenoviral construct encoding the PKG II gene (Ad-PKG II) was used to infect BGC-823 cells, and the activity of the enzyme was induced by cGMP analogue 8-pCPT-cGMP. The proliferation-inhibitory effect of PKG II was analyzed by the MTT assay, BrdU incorporation assay and detection of proliferating cell nuclear antigen (PCNA) expression. Colony formation in soft agarose was performed to analyze the effect of PKG II on the anchorage-independent growth of the cells. The effect of PKG II in vivo was investigated in an immunocompromised nude mice model, and its effect on the cell cycle was analyzed by flow cytometry. The results showed that Ad-PKG II infection increased the expression of PKG II in BGC-823 cells. The activation of PKG II by 8-pCPT-cGMP caused a significant decrease in the number of live cells and inhibited DNA synthesis in individual cells. PKG II activation inhibited the EGF-induced increase in PCNA expression. The activation of PKG II also caused a significant inhibition of colony formation in soft agarose and significantly suppressed the in vivo growth of BGC-823 cells in immunocompromised nude mice. There was substantial cell arrest at the G1 phase and a decrease in the number of S phase cells in the Ad-PKG II/8-pCPT-cGMP-treated cells. These data indicate that the activation of PKG II by 8-pCPT-cGMP inhibits the proliferation of human gastric cancer cells.

Background and Objective: Nitric oxide (NO) is involved in many physiologic and pathologic processes. As an important biologic mediator, NO has been the focus of cancer study for its function in tumorigenesis, tumor progression, and death. This study investigated the effect of NO donor sodium nitroprusside (SNP) on the growth and proliferation of gastric cancer cell line AGS., Methods: The growth inhibition of AGS cells was analyzed using MTT assay. The cell cycle was measured using flow cytometry. The changes of mRNA expression of proliferating cell nuclear antigen (PCNA) and caspase-3 were examined using reverse transcriptase polymerase chain reaction (RT-PCR), and the protein expressions of PCNA and caspase-3 were analyzed using Western blot., Results: Dose-dependent SNP inhibited cell growth and proliferation. When the AGS cells were treated with SNP at 100, 500, 1000, 1500, and 2000 mumol/L for 24 h, the growth inhibition rates were (2.02 +/- 2.96)%, (10.82 +/- 2.21)%, (18.95 +/- 3.35)%, (26.88 +/- 2.54)%, and (42.57 +/- 1.27)%, respectively (P < 0.05). SNP altered the cell cycle in AGS cells. Compared with the control group, treatment with SNP at 100, 500, 1000, 1500, and 2000 mumol/L for 24 h reduced the number of cells in the S phase by 2.29%, 7.8%, 11.34%, 20.49%, and 23.6%, respectively, and enhanced the number of cells in the G1/G0 phases by 3.33%, 9.3%, 13.46%, 21.37%, and 24.73%, respectively (P < 0.05). With the increasing concentration and action time of SNP, the expressions of PCNA mRNA and protein decreased. The expression of caspase-3 mRNA remained unchanged, but procaspase-3 was activated., Conclusion: NO not only inhibits cell growth and proliferation, but also induces apoptosis in gastric cancer cells, and such effects of NO showed significant dose-dependent activity.

Objective: The aim of this study was to explore the effects of breviscapine on the expressions of intercellular adhesion molecule-I (ICAM-I), ATPase activities and oxidative stress in ischaemia-reperfused (I/R) myocardium of diabetic rats., Methods: Sprague Dawley rats were randomly divided into two groups (a diabetic group and a non-diabetic group), and each group divided into two subgroups including a control group and a breviscapine group. Reperfusion surgery was carried out in all rats.The contents of malonaldehyde (MDA), superoxide dismutase (SOD) and glutathione peroxidase (GSH-P(x)) in serum and myocardial tissues were measured. The activities of Na(+)-K(+)-ATPase, Mg(2+)-ATPase, Ca(2+)-ATPase in myocardial mitochondria were measured. The ICAM-I protein expressions in myocardium were determined with the immunohistochemical method., Results: The activities of Na(+)-K(+)-ATPase, Mg(2+)-ATPase, Ca(2+)-ATPase were significantly increased in diabetic rats in the breviscapine group compared with the control group. Compared with the non-diabetic control group, the contents of MDA in serum and myocardium were significantly increased in the diabetic control group. Breviscapine led to a reduction of the contents of MDA in the diabetic and non-diabetic group. Compared with the non-diabetic control group, the activities of SOD and GSH-P(x) in the myocardium were significantly decreased in the diabetic control group.The activities of SOD and GSH-P(x) in serum and myocardium were increased in the diabetic and non-diabetic group after breviscapine treatment. Compared with the non-diabetic control group, the ICAM- I protein expressions were increased significantly in the diabetic control group. Breviscapine decreased the ICAM-I protein expression in the diabetic and the non-diabetic group., Conclusion: Breviscapine may have protective effects on myocardial ischaemia reperfusion injury of diabetic rats by scavenging oxygen free radicals, decreasing the expressions of ICAM-I protein in myocardium and increasing the activities of Na(+)-K(+)-ATPase, Mg(2+)-ATPase, Ca(2+)-ATPase in myocardial mitochondria.

Aim: To elucidate the localization of RhoA in gastric SGC-7901 cancer cells and its translocation by lysophosphatidic acid (LPA) and/or 8-chlorophenylthio-cAMP (CPT-cAMP)., Methods: Immunofluorescence microscopy was used to determine the localization of RhoA. Western blotting was used to detect both endogenous and exogenous RhoA in different cellular compartments (membrane, cytosol, nucleus) and the translocation of RhoA following treatment with LPA, CPT-cAMP, or CPT-cAMP + LPA., Results: Immunofluorescence staining revealed endogenous RhoA to be localized in the membrane, the cytosol, and the nucleus, and its precise localization within the nucleus to be the nucleolus. Western blotting identified both endogenous and exogenous RhoA within different cellular compartments (membrane, cytosol, nucleus, nucleolus). After stimulation with LPA, the amount of RhoA within membrane and nuclear extracts increased, while it decreased in the cytosol fractions. After treatment with CPT-cAMP the amount of RhoA within the membrane and the nuclear extracts decreased, while it increased within the cytosol fraction. Treatment with a combination of both substances led to a decrease in RhoA in the membrane and the nucleus but to an increase in the cytosol., Conclusion: In SGC-7901 cells RhoA was found to be localized within the membrane, the cytosol, and the nucleus. Within the nucleus its precise localization could be demonstrated to be the nucleolus. Stimulation with LPA caused a translocation of RhoA from the cytosol towards the membrane and the nucleus; treatment with CPT-cAMP caused the opposite effect. Furthermore, pre-treatment with CPT-cAMP was found to block the effect of LPA.

Aim: To elucidate the localization of vasodilator stimulated phosphoprotein (VASP), a cytoskeletal organizing protein and a substrate of protein kinases A and G in mitotic gastric cancer cells., Methods: Immunofluorescence microscopy was used to observe the localization of alpha-tubulin, VASP and Ser157 phosphorylated VASP (p-VASP) in interphase of mitotic gastric cancer of the cell line SGC-7901., Results: Immunofluorescence staining showed that p-VASP but not VASP was co-localized with alpha-tubulin on spindle poles and fibers in prophase, metaphase and anaphase of the mitotic process of the gastric cancer cell line SGC-7901. H89, an inhibitor of protein kinases A and G, had no effect on the localization of p-VASP on the spindles., Conclusion: VASP may play a role in assembling and stabilizing the mitotic spindle of cells, and phosphorylation of the protein is the precondition for it to exert this function.

Aim: To explore the mechanism by which H pylori causes activation of gastric epithelial cells., Methods: A VacA (+) and CagA (+) standard H pylori line NCTC 11637 and a human gastric adenocarcinoma derived gastric epithelial cell line BGC-823 were applied in the study. MTT assay and (3)H-TdR incorporation test were used to detect the proliferation of BGC-823 cells and Western blotting was used to detect the activity and existence of related proteins., Results: Incubation with H pylori extract increased the proliferation of gastric epithelial cells, reflected by both live cell number and DNA synthesis rate. The activity of extracellular signal-regulated protein kinase (ERK) signal transduction cascade increased within 20 min after incubation with H pylori extract and appeared to be a sustained event. MAPK/ERK kinase (MEK) inhibitor PD98059 abolished the action of H pylori extract on both ERK activity and cell proliferation. Incubation with H pylori extract increased c-Fos expression and SRE-dependent gene expression. H pylori extract caused phosphorylation of several proteins including a protein with molecular size of 97.4 kDa and tyrosine kinase inhibitor genistein inhibited the activation of ERK and the proliferation of cells caused by H pylori extract., Conclusion: Biologically active elements in H pylori extract cause proliferation of gastric epithelial cells through activating tyrosine kinase and ERK signal transduction cascade.