Differential Expression of KIF18B in Gastric Cancer and Its Role in Chemotherapy Sensitivity.

Gastric cancer (GC) is a main cause of cancer death in the world, and improving the chemotherapy sensitivity can enhance the chemotherapy efficacy of GC. The study objective is to explore the differential KIF18B expression in GC and its effect on GC chemotherapy sensitivity. The KIF18B expression in GC tissues and adjacent normal tissues was analyzed by real-time quantitative polymerase chain reaction. The relationship between differential KIF18B expression and different clinicopathological features was detected. It was found that KIF18B was highly expressed in GC tissues, and KIF18B expression was differential in patients with different clinicopathological features. The upregulation of KIF18B has a positive correlation with the poor therapeutic effect and high KIF18 was associated with lower 3-year overall survival and disease-free survival. The KIF18B-downregulated NCI-N87 cells were constructed and tested by cell counting kit-8 assay and colony formation. Cell migration and invasion were detected by Transwell assay. The xenograft tumor model was established to observe the effect of KIF18B on the efficacy of chemotherapy. The upregulation of KIF18B reduced the chemotherapy sensitivity of GC cells and enhanced their proliferation, migration, and invasion. Silencing KIF18B inhibited tumor growth and promoted chemotherapy efficacy in vivo. In summary, KIF18B inhibitor may have a potential function for improving the efficacy of chemotherapy in GC.

Serum basic fibroblast growth factor and interleukin-1ß predict the effect of first-line chemotherapy in patients with advanced gastric cancer.

BACKGROUND: The incidence and mortality rates of gastric cancer in China are the second-highest in the world, and most patients with gastric cancer lose their chance of surgery by the time of their diagnosis. AIM: To explore the predictive potential of serum basic fibroblast growth factor and interleukin-1ß levels for the effect of first-line chemotherapy in patients with advanced gastric cancer. METHODS: From the gastric cancer patients admitted to our hospital from May 2019 to April 2023, 84 patients were selected and randomly and equally assigned to the experimental or control group. The FLOT group received the FLOT chemotherapy regimen (composed of oxaliplatin + calcium folinate + fluorouracil + paclitaxel), while the SOX group received the SOX chemotherapy regimen (composed of oxaliplatin + tiga capsules). The clinical efficacy, tumor marker levels, adverse reactions, and survival rates of the two groups were compared 7 days after the end of the relevant treatments. RESULTS: The target effective rate of the FLOT group was 54.76%, which was much higher than that of the SOX group (33.33%; P < 0.05). After treatment, both the groups demonstrated lower levels of cancer antigen (CEA), carbohydrate antigen 199 (CA199), and peptide tissue antigen (TPS). For several patients before treatment (P < 0.05). Third and fourth grades. In terms of adverse reactions, the level of white blood cells in both the groups was lower. Moreover, the incidence of hand-foot skin reactions in these two study groups was lower (P < 0.05), while those of peripheral neuritis, vomiting, diarrhea, and abnormal liver function were significant (P < 0.05). No statistically significant difference was noted between the two groups (P < 0.05). The 1-year survival rate was higher in the FLOT group (P < 0.05). CONCLUSION: The FLOT regimen was effective in reducing the serum CEA, CA199, and TPS levels as well as in improving the 1-year survival rate of patients with good tolerability, making it worthy of clinical promotion and application.

Klotho, an anti-senescence related gene, is frequently inactivated through promoter hypermethylation in colorectal cancer.

The potential anti-senescence gene Klotho (KL) has been recently found to participate in the progression of several different human cancers including breast, lung, and cervical cancer. In this current study, we identified KL as a candidate tumor suppressor gene silenced through promoter hypermethylation in colorectal cancer (CRC). KL gene expression is found to be absent or reduced in colon cancer cell lines (5/6, 83.3%), which can be reversed by treatment with demethylation agent 5-aza-2'-deoxycytidine (Aza), but not HDAC inhibitor trichostatin A. In addition, KL expression is markedly downregulated in colorectal carcinoma tissues when compared to the adjacent nontumor tissues (n=25, p<0.001). The methylation of the KL gene promoter was frequently detected in primary tumor tissues (34/40, 85%) when compared with adjacent nontumor colon tissues. Furthermore, ectopic expression of KL led to the cell proliferation inhibition of colon cancer cell lines via the induction of cell apoptosis and S-phase cell cycle arrest. Taken together, our results suggest that KL is inactivated through promoter hypermethylation and potentially functions as a tumor suppressor gene in CRC.

[DNA methylation of ZIC1 and KLOTHO gene promoters in colorectal carcinomas and its clinicopathological significance].

OBJECTIVE: To determine DNA methylation status of ZIC1 and KLOTHO gene in colorectal carcinomas and its relationship with clinicopathological features of patients. METHODS: The mRNA expression of ZIC1 and KLOTHO genes in colorectal carcinomas was detected by real-time quantitative RT-PCR, and the promoter methylation status was detected by methylation specific PCR (MSP). The relationship of ZIC1 and KLOTHO methylation status with clinicopathological features of colorectal carcinoma was analyzed. RESULT: The mRNA expression levels of ZIC1 and KLOTHO genes were significantly down-regulated in tumor tissues when compared to adjacent nontumor tissues (P<0.001). ZIC1 and KLOTHO methylation was detected in 80.0%(20/25) and 76.0%(19/25) of colorectal tumor tissues, respectively, and the both positive rate was 64.0%(16/25). CONCLUSION: The down-regulated expression of ZIC1 and KLOTHO in colorectal carcinoma may relate to promoter methylation. The detection of methylation of ZIC1 and KLOTHO gene potentially provides biomarkers for diagnosis of colorectal carcinoma.

[Construction of COL1A1 short hairpin RNA vector and its effect on cell proliferation and migration of gastric cancer cells].

OBJECTIVE: To construct COL1A1-targeted short hairpin RNA (shRNA) vector with pSilencer 4.1-CMV neo siRNA expression vector and to evaluate its effect on proliferation and migration of gastric cancer BGC-823 cells in vitro. METHODS: Three COL1A1-shRNA plasmids (COL1A1-shRNA-1, COL1A1-shRNA-2, COL1A1-shRNA-3), targeting different sites of COL1A1 gene, were constructed using pSilencer 4.1-CMV neo siRNA expression vector and transfected into gastric cancer BGC-823 cells. Real time quantitative RT-PCR and Western blot were performed to detect expression levels of COL1A1. MTT and Transwell migration assays were employed to evaluate the effects of COL1A1 gene silence on cell proliferation and migration. RESULT: Three recombinant plasmids targeting COL1A1 were constructed successfully. The expressions of COL1A1 in BGC-823 cells, including mRNA and protein levels, were significantly inhibited by the COL1A1-shRNA transfectants, which resulted in a clear reduction of cell proliferation and migration capacity. CONCLUSION: The COL1A1-shRNA can effectively knock down gene expression and inhibit proliferation and migration of gastric cancer BGC-823 cells.

XPD inhibits cell growth and invasion and enhances chemosensitivity in esophageal squamous cell carcinoma by regulating the PI3K/AKT signaling pathway.

Esophageal squamous cell carcinoma (ESCC) is a lethal disease due to its high aggressiveness. The aim of the present study was to investigate the role of xeroderma pigmentosum complementation group D (XPD) in the growth and invasion of ESCC and to elucidate the potential underlying molecular mechanisms. Western blot analysis and RT­qPCR were used to detect the expression level of XPD in ESCC tissue samples and adjacent normal esophageal tissue samples. The pEGFP­N2/XPD plasmid was transfected into human ESCC cell lines (EC9706 and EC109). The proliferation, apoptosis, migration and invasion of EC9706 or EC109 cells were assessed following transfection with the XPD overexpression plasmid. The chemosensitivity of EC9706 or EC109 cells to cisplatin or fluorouracil was evaluated by CCK­8 assay. The expression levels of phosphoinositide 3­kinase (PI3K)/AKT, nuclear factor (NF)­κB, Janus kinase 2 (JAK2)/signal transducer and activator of transcription 3 (STAT3) and mitogen­activated protein kinase (MAPK) signaling pathway­related genes were detected by RT­qPCR and western blot analysis. The results demonstrated that the expression level of XPD was markedly lower in ESCC tissue samples than in adjacent normal esophageal tissue samples. The pEGFP­N2/XPD plasmid was successfully transfected into EC9706 or EC109 cells, inducing XPD overexpression. A High XPD expression markedly suppressed cell proliferation, migration and invasion, and increased the apoptotic rate of EC9706 and EC109 cells. Furthermore, the overexpression of XPD significantly increased the chemosensitivity of EC9706 and EC109 cells to cisplatin or fluorouracil. Following XPD overexpression, the expression levels of PI3K, p­AKT, c­Myc, Cyclin D1, Bcl­2, vascular endothelial growth factor (VEGF) and matrix metalloproteinase (MMP)­9 were markedly downregulated, while the expression level of p21 was markedly upregulated. On the whole, the findings of the present study demonstrate that XPD inhibits the growth and invasion of EC9706 and EC109 cells, whilst also enhancing the chemosensitivity of EC9706 and EC109 cells to cisplatin or fluorouracil by regulating the PI3K/AKT signaling pathway. XPD may thus be an underlying target for ESCC treatment and drug resistance.

pH dependence of the binding interactions between humic acids and bisphenol A - A thermodynamic perspective.

The wide application of bisphenol A (BPA) leads to the emergence of BPA residuals in natural water environments. Dissolved organic matter (DOM) existed in water can bind with BPA, hence influencing the migration and transformation of BPA in aquatic environments. pH is a crucial factor governing the binding interactions between DOM and BPA. However, the mechanisms driven the binding process under different pH conditions are still unclear. In this study, the interactions between BPA and humic acids (HA), a primary component of DOM, are investigated over a wide pH range of 3-12 by integrating fluorescence quenching, dynamic light scattering and microcalorimetry. pH dependence of the binding interactions between HA and BPA are interpreted from a thermodynamic perspective. The results indicate that HA can spontaneously interact with BPA to form a stable HA-BPA complex. With the increasing pH, the binding interactions change from entropy driven to entropy-enthalpy co-driven. Hydrophobic force dominate the binding interactions under acidic condition. The synergy of hydrophobic force and hydrogen bond promotes the binding process under neutral condition. Under alkaline conditions, electrostatic repulsion participates the binding process in addition to hydrophobic force and hydrogen bond, weakening the binding strength. Therefore, neutral pH is favorable for HA to bind with BPA, consequently enhancing the dissolution of BPA in natural water bodies. The results are beneficial to better understand the pH dependent distribution of BPA in aquatic environments.

Insights into thermodynamic mechanisms driving bisphenol A (BPA) binding to extracellular polymeric substances (EPS) of activated sludge.

Bisphenol A (BPA) in wastewater has high risks of causing biological feminization. During the wastewater treatment process, large amounts of BPA are accumulated in activated sludge. However, the mechanisms of BPA interacted with activated sludge are still unclear. Especially, the roles of extracellular polymeric substances (EPS), which are major components of activated sludge, in the removal of BPA have never been concerned. In this study, the binding interactions between sludge EPS and BPA are explored combining fluorescence spectroscopy and dynamic light scattering. The thermodynamic mechanisms driving the binding behavior of BPA to EPS are illustrated by isothermal titration calorimetry. The results indicate that the binding interaction between BPA and EPS is spontaneous. BPA mainly binds with the proteins of EPS by hydrophobic association. The random-coiled structure of EPS transforms into relatively condensed cores after binding with BPA. A neutral pH, high ionic strength, and high temperature promote the binding process, facilitating to stabilize BPA in sludge EPS. This study provides new insights into the roles of sludge EPS in the migration and removal of BPA in activated sludge system.

[Role of leptin in the pathogenesis of obesity-related hypertension].

OBJECTIVE: To assess the role of leptin in the pathogenesis of obesity-related hypertension and the relationship between blood pressure (BP), and body mass index (BMI), insulin resistance and leptin were examined. METHODS: 560 non-diabetic men, aged 35 - 75, selected from volunteers of health screening test during 2 000 were divided into hypertension group (n = 321, BP >or= 140/90 mm Hg without antihypertensive medication). and normal blood pressure group (n = 239). The body weight, waist hip ratio,BP, plasma glucose, serum lipids, true insulin (TI) and leptin were measured after overnight fast. Insulin sensitivity was assessed by the HOMA insulin resistance index (HOMA-R). RESULTS: Fasting leptin level showed good correlation with BMI, fasting TI, HOMA-R, BP and also triglycerides (all P < 0.01). After adjustment for age, BMI and HOMA-R, serum leptin was still positively correlated to SBP (r = 0.11, P < 0.05), and was significantly higher in hypertensive subjects than in normotensive subjects (geometric mean 6.4 vs 4.7 micro g/L, P < 0.001). Logistic regression analysis demonstrated that leptin remained significantly associated with hypertension after adjustment for potentially confounding factors. CONCLUSION: Leptin may play an important role in the pathogenesis of obesity related hypertension.