Predictive value of preoperative CT enhancement rate and CT perfusion parameters in colorectal cancer.

BACKGROUND: Angiogenesis is a critical step in colorectal cancer growth, progression and metastasization. CT are routine imaging examinations for preoperative clinical evaluation in colorectal cancer patients. This study aimed to investigate the predictive value of preoperative CT enhancement rate (CER) and CT perfusion parameters on angiogenesis in colorectal cancer, as well as the association of preoperative CER and CT perfusion parameters with serum markers. METHODS: This retrospective analysis included 42 patients with colorectal adenocarcinoma. Median of microvessel density (MVD) as the cut-off value, it divided 42 patients into high-density group (MVD ≥ 35/field, n = 24) and low-density group (MVD < 35/field, n = 18), and 25 patients with benign colorectal lesions were collected as the control group. Statistical analysis of CER, CT perfusion parameters, serum markers were performed in all groups. Receiver operating curves (ROC) were plotted to evaluate the diagnostic efficacy of relevant CT perfusion parameters for tumor angiogenesis; Pearson correlation analysis explored potential association between CER, CT perfusion parameters and serum markers. RESULTS: CER, blood volume (BV), blood flow (BF), permeability surface (PS) and carbohydrate antigen 19 - 9 (CA19-9), carbohydrate antigen 125 (CA125), carcinoembryonic antigen (CEA), trefoil factor 3 (TFF3), vascular endothelial growth factor (VEGF) in colorectal adenocarcinoma were significantly higher than those in the control group, the parameters in high-density group were significantly higher than those in the low-density group (P < 0.05); however, the time to peak (TTP) of patients in colorectal adenocarcinoma were significantly lower than those in the control group, and the high-density group showed a significantly lower level compared to the low-density group (P < 0.05). The combined parameters BF + TTP + PS and BV + BF + TTP + PS demonstrated the highest area under the curve (AUC), both at 0.991. Pearson correlation analysis showed that the serum levels of CA19-9, CA125, CEA, TFF3, and VEGF in patients showed positive correlations with CER, BV, BF, and PS (P < 0.05), while these indicators exhibited negative correlations with TTP (P < 0.05). CONCLUSIONS: Some single and joint preoperative CT perfusion parameters can accurately predict tumor angiogenesis in colorectal adenocarcinoma. Preoperative CER and CT perfusion parameters have certain association with serum markers.

The P1 protein of wheat yellow mosaic virus exerts RNA silencing suppression activity to facilitate virus infection in wheat plants.

Wheat yellow mosaic virus (WYMV) causes severe wheat viral disease in Asia. However, the viral suppressor of RNA silencing (VSR) encoded by WYMV has not been identified. Here, the P1 protein encoded by WYMV RNA2 was shown to suppress RNA silencing in Nicotiana benthamiana. Mutagenesis assays revealed that the alanine substitution mutant G175A of P1 abolished VSR activity and mutant Y10A VSR activity remained only in younger leaves. P1, but not G175A, interacted with gene silencing-related protein, N. benthamiana calmodulin-like protein (NbCaM), and calmodulin-binding transcription activator 3 (NbCAMTA3), and Y10A interacted with NbCAMTA3 only. Competitive Bimolecular fluorescence complementation and co-immunoprecipitation assays showed that the ability of P1 disturbing the interaction between NbCaM and NbCAMTA3 was stronger than Y10A, Y10A was stronger than G175A. In vitro transcript inoculation of infectious WYMV clones further demonstrated that VSR-defective mutants G175A and Y10A reduced WYMV infection in wheat (Triticum aestivum L.), G175A had a more significant effect on virus accumulation in upper leaves of wheat than Y10A. Moreover, RNA silencing, temperature, and autophagy have significant effects on the accumulation of P1 in N. benthamiana. Taken together, WYMV P1 acts as VSR by interfering with calmodulin-associated antiviral RNAi defense to facilitate virus infection in wheat, which has provided clear insights into the function of P1 in the process of WYMV infection.

Efficacy and optimal combination timing of chemotherapy combined with PD-1 inhibitor in advanced cervical cancer: a multicenter retrospective cohort study.

Background: This study aimed to investigate the efficacy and safety of chemotherapy combined with programmed cell death protein 1 (PD-1) inhibitors in the treatment of advanced cervical cancer and the effect of optimal combination timing on prognosis. Methods: From March 2020 to December 2021, the clinical data of 116 patients with advanced cervical cancer who received PD-1 inhibitors combined with chemotherapy were collected. The clinical characteristics and adverse events of the patients were recorded until the cut-off date of follow-up. The primary endpoints were progression-free survival (PFS), the objective response rate (ORR), and safety; the secondary endpoints were the disease-control rate (DCR) and overall survival (OS). Multivariate Cox proportional hazards regression was used to analyze the prognostic factors affecting the PFS of patients and to assess the effect of the timing of combination therapies on PFS. Results: In total, 85 patients from 4 study centers were included in this study. The median PFS was 10.3 months [95% confidence interval (CI): 9.47-11.13 months], the ORR was 44.7%, the DCR was 75.3%, and the median OS was not reached. The multivariate Cox proportional hazards regression analysis showed that the early combination of chemotherapy with a PD-1 inhibitor provided better PFS than the late combination [hazard ratio (HR) 0.40, 95% CI: 0.24-0.67, P=0.001]. Lymph node metastasis (HR 2.04, 95% CI: 1.24-3.38, P=0.005), and previous treatment (HR 1.79, 95% CI: 1.09-3.00, P=0.023) were also independent risk factors for PFS. During the treatment and follow-up periods, the overall incidence of adverse events in this study was 56.5%, and that of grade ≥3 adverse events was 12.9%. Thrombocytopenia, neutropenia, anemia, and hypothyroidism were the main treatment-related adverse events, all of which were tolerated, and no serious adverse events leading to death were observed. There were no treatment-related deaths. Conclusions: PD-1 inhibitors combined with chemotherapy have good efficacy and controllable safety in patients with advanced cervical cancer. The early combination of PD-1 inhibitors and chemotherapy may provide better survival benefits than the late combination for patients.

Role of METTL3-Dependent N6-Methyladenosine mRNA Modification in the Promotion of Angiogenesis.

Epigenetic alterations occur in many physiological and pathological processes. N6-methyladenosine (m6A) modification is the most prevalent modification in eukaryotic mRNAs. However, the role of m6A modification in pathological angiogenesis remains elusive. In this study, we showed that the level of m6A modification was significantly upregulated in endothelial cells and mouse retinas following hypoxic stress, which was caused by increased METTL3 levels. METTL3 silencing or METTL3 overexpression altered endothelial cell viability, proliferation, migration, and tube formation in vitro. METTL3 knockout in vivo decreased avascular area and pathological neovascular tufts in an oxygen-induced retinopathy model and inhibited alkali burn-induced corneal neovascularization. Mechanistically, METTL3 exerted its angiogenic role by regulating Wnt signaling through the m6A modification of target genes (e.g., LRP6 and dishevelled 1 [DVL1]). METTL3 enhanced the translation of LRP6 and DVL1 in an YTH m6A RNA-binding protein 1 (YTHDF1)-dependent manner. Collectively, this study suggests that METTL3-mediated m6A modification is an important hypoxic stress-response mechanism. The targeting of m6A through its writer enzyme METTL3 is a promising strategy for the treatment of angiogenic diseases.

[Dynamic changes of TGF-α and TGF-ß1 in rats with liver cirrhosis induced by multiple pathogenic factors].

OBJECTIVE: To explore the dynamic changes of transforming growth factor-α (TGF-α) and transforming growth factor-ß1 (TGF-ß1) of liver cirrhosis induced by multiple pathogenic factors in rats. METHODS: Animals in the cirrhosis group were fed a mixture of maize flour, lard, cholesterol and alcohol plus subcutaneously injection with carbon tetrachloride (CCl4), the CCl4(0.5 ml/100 g · w) was injected at the first day of experiment and the 40% CCl4oil solution (0.3 ml /100 g · w) was injected at an interval of three days. The thirty-six male SD rats were randomly divided into liver cirrhosis group of the 4th, 6th and 8 th week, and normal control group of the 4th, 6th and 8th week. The contents of alanine transferase (ALT), endotoxin, tumor necrosis factor-α (TNF-α) and homocysteine (Hcy) in plasma were evaluated. Histopathological changes of the liver were observed under microscope with the staining of HE. The expressions of TGF-α and TGF-ß1 were analyzed by the method of immunohistochemistry. RESULTS: Compared with the corresponding normal control group, the levels of ALT, endotoxin, TNF-α and Hcy in plasma were gradually significantly increased in liver cirrhosis group of the 4th, 6th and 8th week (P < 0.05); the expression of TGF-α in the liver tissues was significantly increased at the 4th week (P < 0.05); the expression of TGF-ß1 in the liver tissues was gradually significantly increased in every model group (P < 0.05). CONCLUSION: In the formation process of cirrhosis, the expression of TGF-α was increased in liver of cirrhosis group at the 4th week, and later it was suppressed; the expression of TGF-ß1 was continuously increased. The characteristic dynamic changes of TGF-α and TGF-ß1 might be related to sustained endotoxemia, the high level of TNF-α and hyperhomocysteinemia.

Effect of artesunate supplementation on bacterial translocation and dysbiosis of gut microbiota in rats with liver cirrhosis.

AIM: To evaluate the effect of artesunate (AS) supplementation on bacterial translocation (BT) and gut microbiota in a rat model of liver cirrhosis. METHODS: Fifty-four male Sprague-Dawley rats were randomly divided into a normal control group (N), a liver cirrhosis group (M) and a liver cirrhosis group intervened with AS (MA). Each group was sampled at 4, 6 and 8 wk. Liver cirrhosis was induced by injection of carbon tetrachloride (CCl4), intragastric administration of 10% ethanol, and feeding a high fat diet. Rats in the MA group were intragastrically administered with AS (25 mg/kg body weight, once daily). Injuries of the liver and intestinal mucosa were assessed by hematoxylin-eosin or Masson's trichrome staining. Liver index was calculated as a ratio of the organ weight (g) to body weight (g). The gut microbiota was examined by automated ribosomal intergenic-spacer analysis of fecal DNA. BT was assessed by standard microbiological techniques in the blood, mesenteric lymph nodes (MLNs), liver, spleen, and kidney. RESULTS: Compared to group N, the body weight was reduced significantly in groups M and MA due to the development of liver cirrhosis over the period of 8 wk. The body weight was higher in group MA than in group M. The liver indices were significantly elevated at 4, 6 and 8 wk in groups M and MA compared to group N. AS supplementation partially decreased the liver indices in group MA. Marked histopathologic changes in the liver and small intestinal mucosa in group M were observed, which were alleviated in group MA. Levels of pro-inflammatory interleukin-6 and tumor necrosis factor-α were significantly elevated at 8 wk in ileal homogenates in group M compared to group N, which were decreased after AS supplementation in group MA. The dysbiosis of gut microbiota indicated by the mean diversity (Shannon index) and mean similarity (Sorenson index) was severe as the liver cirrhosis developed, and AS supplementation had an apparent intervention effect on the dysbiosis of gut microbiota at 4 wk. The occurrence of BT was increased in the liver of group M compared to that of group N. AS supplementation reduced BT in group MA at 8 wk. BT also occurred in the MLNs, spleen, and kidney, which was reduced by AS supplementation. BT was not detected in the blood in any group. CONCLUSION: Dysbiosis of gut microbiota, injury of intestinal mucosal barrier and BT occurred as liver cirrhosis progressed, which might enhance inflammation and aggravate liver injury. AS may have other non-antimalarial effects that modulate gut microbiota, inhibit BT and alleviate inflammation, resulting in a reduction in CCl4, alcohol and high fat-caused damages to the liver and intestine.

Breastfeeding and maternal hypertension and diabetes: a population-based cross-sectional study.

OBJECTIVE: This study aimed to assess the association of breastfeeding and maternal hypertension and diabetes in Beijing, China. SUBJECTS AND METHODS: A cross-sectional study was conducted in four urban communities of Beijing, China, with 9,128 parous women 40-81 years of age who had had only one lifetime birth. Each participant completed a detailed survey and accepted blood pressure measurement and blood glucose testing. Moreover, self-reported hypertension and diabetes were confirmed by review of medical records. RESULTS: After the analysis was adjusted for the potential confounders, including age, body mass index (BMI), waist to hip ratio (WHR), working status, educational level, drinking, smoking, family history of hypertension, age of menarche, menopause, oral contraceptive use, age of child-bearing, and postpartum BMI, the odd ratio (OR) of hypertension was 1.18 (95% confidence interval [CI], 1.05-1.32) for women who did not breastfeed, compared with women who did. In addition, the ORs for >0 to 6 months, >6 to 12 months, and >12 months of breastfeeding were 0.87 (95% CI, 0.76-0.99), 0.83 (95% CI, 0.68-1.00), and 0.79 (95% CI, 0.65-0.97), respectively, compared with women who did not breastfeed. With adjustment for age, WHR, working status, educational level, family history of diabetes, and postpartum BMI, women who did not breastfeed increased the risk of diabetes (OR=1.30; 95% CI, 1.11-1.53) compared with women who did. Moreover, women who breastfed for >0 to 6 months (OR=0.81; 95% CI, 0.67-0.98) and >6 to 12 months (OR=0.46; 95% CI, 0.26-0.84) had a lower risk of diabetes, compared with women who did not breastfeed. CONCLUSIONS: Chinese mothers who did not breastfeed were more likely to develop hypertension and diabetes in later life.

[Protective effect of tanshinol on the hepatopulmonary syndrome in rat].

OBJECTIVE: To explore the mechanism of tanshinol on alleviate the inflammatory injury of lung tissue in rat hepatopulmonary syndrome (HPS). METHODS: SD rats were randomly divided into normal control group (n = 8), hepatopulmonary syndrome (HPS) group (n = 11) and tanshinol intervention group (n = 9). HE staining was used to observe the histopathology changes of pulmonary and hepatic tissues, and to count the number of macrophages in lung tissues. The activity of alanine transferase (ALT) and concentrations of endotoxin, tumor necrosis factor-a (TNF-alpha) and homocystein (Hcy) in plasma were detected. The concentrations of TNF-alpha, nitric oxide (NO) and malondialdehyde (MDA) and the activity of inducible nitric oxide synthase (iNOS) in the lung tissues were measured, respectively. RESULTS: Thickened alveolar septum and increased macrophages were observed in lungs in HPS rat. After administered with tanshinol, the pulmonary pathological changes were alleviated and the number of macrophages in lung tissue was decreased compared with HPS group. The activity of ALT and the concentrations of endotoxin, TNF-alpha and Hcy in plasma ,and TNF-alpha, iNOS, NO and MDA in lung tissue in HPS group were higher than those of normal control group; meanwhile, those tanshinol group were less those that of HPS group. CONCLUSION: Tanshinol may play an important role in delaying the development of HPS through protecting liver or directly antagonizing the effect of intestinal endotoxemia so as to alleviate the inflammatory reaction in lung tissue.

Exploration of molecular mechanisms of diffuse large B-cell lymphoma development using a microarray.

OBJECTIVE: We aimed to identify key genes, pathways and function modules in the development of diffuse large B-cell lymphoma (DLBCL) with microarray data and interaction network analysis. METHODS: Microarray data sets for 7 DLBCL samples and 7 normal controls was downloaded from the Gene Expression Omnibus (GEO) database and differentially expressed genes (DEGs) were identified with Student's t-test. KEGG functional enrichment analysis was performed to uncover their biological functions. Three global networks were established for immune system, signaling molecules and interactions and cancer genes. The DEGs were compared with the networks to observe their distributions and determine important key genes, pathways and modules. RESULTS: A total of 945 DEGs were obtained, 272 up-regulated and 673 down-regulated. KEGG analysis revealed that two groups of pathways were significantly enriched: immune function and signaling molecules and interactions. Following interaction network analysis further confirmed the association of DEGs in immune system, signaling molecules and interactions and cancer genes. CONCLUSIONS: Our study could systemically characterize gene expression changes in DLBCL with microarray technology. A range of key genes, pathways and function modules were revealed. Utility in diagnosis and treatment may be expected with further focused research.

[Clinicalpathological characteristics of Lynch syndrome related epithelial ovarian cancer].

OBJECTIVE: To explore the clinical pathological characteristics of Lynch syndrome associated ovarian cancer. METHODS: Totally 260 cases ovarian cancer patients were admitted to Tianjin Medical University General Hospital during Jan. 2004 and Jan. 2011, among which 10 patients (LS group) belonged to Lynch syndrome associated ovarian cancer according to Amsterdam II criteria. One hundred ovarian cancer patients without any family cancer history were enrolled randomizely as control group (sporadic group). RESULTS: Lynch syndrome associated ovarian cancer accounted for 3.8% (10/260), the incidence rate of ovarian cancer for female family members of Lynch syndrome was 8.7% (10/115). Mean age at time of diagnosis in LS group was (46 ± 7) years, significantly earlier than that in sporadic group [(56 ± 11) years, P < 0.05]. There was no statistical difference between two groups in histological type or International Federation of Gynecology and Obstetrics (FIGO) stage (P > 0.05). Most of the tissue differentiation in LS group were well or moderate differentiated, there was statistical difference between the two groups (9/10 vs. 55%, P < 0.05). The 3-year and 5-year survival rate in LS group were 87.5% and 52.5% respectively, compared with 55.4%and 22.7% in sporadic group (all P < 0.05). CONCLUSION: Compared with sporadic ovarian cancer, Lynch syndrome associated ovarian cancer is more likely present as the clinical pathological characteristics of early age of onset, serous adenocarcinoma, lower grade and better prognosis.

Targeting the intrinsic inflammatory pathway: honokiol exerts proapoptotic effects through STAT3 inhibition in transformed Barrett's cells.

One way to link chronic inflammation with cancer is through the intrinsic inflammatory pathway, in which genetic alterations that induce malignant transformation also produce a cancer-promoting, inflammatory microenvironment. Signal transducer and activator of transcription 3 (STAT3) contributes to the intrinsic inflammatory pathway in Barrett's esophagus. In human tumors, honokiol (a polyphenol in herbal teas) has growth-inhibitory and proapoptotic effects associated with suppressed activation of STAT3. We used human Barrett's epithelial and esophageal adenocarcinoma cell lines to determine effects of honokiol on cell number, necrosis, apoptosis, and anchorage-independent growth and to explore STAT3's role in those effects. We determined Ras activity and expression of phosphorylated ERK1/2, phosphorylated Akt, and phosphorylated STAT3 in the presence or absence of honokiol. Cells were infected with constitutively active Stat3-C to assess effects of honokiol-induced STAT3 inhibition on apoptosis. Honokiol decreased cell number and increased necrosis and apoptosis in transformed Barrett's cells, but not in nontransformed cells. In adenocarcinoma cells, honokiol also increased necrosis and apoptosis and decreased anchorage-independent growth. Within 30 min of honokiol treatment, transformed Barrett's cells decreased expression of phosphorylated STAT3; decreases in Ras activity and phosphorylated ERK1/2 expression were detected at 24 h. Infection with Stat3-C significantly reduced apoptosis after honokiol treatment. Honokiol causes necrosis and apoptosis in transformed Barrett's and esophageal adenocarcinoma cells, but not in nontransformed Barrett's cells, and the proapoptotic effects of honokiol are mediated by its inhibition of STAT3 signaling. These findings suggest a potential role for targeting the intrinsic inflammatory pathways as a therapeutic strategy to prevent Barrett's carcinogenesis.

[Activation and significance of the PI3K/Akt pathway in endometrium with polycystic ovary syndrome patients].

OBJECTIVE: To investigate activation of the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt) pathway in the endometrium of women with polycystic ovary syndrome (PCOS) and its role in endometrium hyperplasia and carcinogenesis, and the factors affecting the activation of the PI3K/Akt pathway. METHODS: From Jan 2007 to Jun 2008, 52 patients with PCOS who underwent dilatation and curettage were selected as experimental group matched with 32 non-PCOS patients as control group. Serous hormonal parameters, fasting blood glucose and insulin, body mass index (BMI), and endometrium pathology were measured and evaluated in all patients. The PCOS patients were divided into insulin resistance and non-insulin resistance group according to homeostasis model assessment-insulin resistance index (HOMA-IR). Meanwhile, the PCOS patients were grouped as normal, endometrial hyperplasia and carcinoma depending on outcome of pathology. The expression of Akt and phosphorylated Akt (p-Akt) were determined by western blot. RESULTS: (1) The expression of p-Akt was significantly higher in PCOS group [(46 ± 18)%] than that in control [(33 ± 9)%, P < 0.01)]. (2) The expression of p-Akt was significantly higher in group of endometrial hyperplasia and carcinoma [(56 ± 19)%] when compared with those in normal endometria group [(31 ± 12)%, P < 0.05]; the expression of p-Akt was significantly higher in group of insulin resistance [(50 ± 19)%] compared with that in non-insulin resistance group [(34 ± 10)%, P < 0.01]. (3) There was a positive correlation between the expression level of p-Akt in endometrium with PCOS and HOMA-IR and BMI respectively (r = 0.400, 0.326, both P < 0.05). CONCLUSIONS: The PI3K/Akt pathway was over activated in endometrium with PCOS which may be associated with the formation of endometrial hyperplasia and carcinoma in PCOS patients. Insulin resistance and obesity may be high risk factors for over-activation of the PI3K/Akt pathway in endometrium with PCOS.

Cancer-related inflammation and Barrett's carcinogenesis: interleukin-6 and STAT3 mediate apoptotic resistance in transformed Barrett's cells.

Cancer-related inflammation recently has been proposed as a major physiological hallmark of malignancy. Some genetic alterations known to promote cellular proliferation and induce malignant transformation also may participate in an intrinsic inflammatory pathway that produces a cancer-promoting inflammatory microenvironment. Little is known about this intrinsic inflammatory pathway in Barrett's esophagus. We have used a series of nontransformed and transformed human Barrett's epithelial cell lines developed in our laboratory to explore the potential contribution of interleukin (IL)-6 and signal transducer and activator of transcription (STAT3) (key molecules in the intrinsic inflammatory pathway) to Barrett's carcinogenesis. We determined IL-6 mRNA expression and protein secretion and protein expression of activated phospho-STAT3 and its downstream target myeloid cell leukemia (mcl)-1 (Mcl-1). We used an IL-6 blocking antibody and two JAK kinase inhibitors (AG490 and JAK inhibitor I) to assess whether STAT3 activation is IL-6 dependent. We also used small interfering RNAs (siRNAs) to STAT3 and Mcl-1 to assess effects of STAT3 pathway inhibition on apoptosis. Phospho-STAT3 was expressed only by transformed Barrett's cells, which also exhibited higher levels of IL-6 mRNA and of IL-6 and Mcl-1 proteins than nontransformed Barrett's cells. STAT3 phosphorylation could be blocked by IL-6 blocking antibody and by AG490 and JAK inhibitor I. In transformed Barrett's cells, rates of apoptosis following exposure to deoxycholic acid were significantly increased by transfection with siRNAs for STAT3 and Mcl-1. We conclude that activation of the IL-6/STAT3 pathway in transformed Barrett's epithelial cells enables them to resist apoptosis. These findings demonstrate a possible contribution of the intrinsic inflammatory pathway to carcinogenesis in Barrett's esophagus.

[Extracellular signal-regulated protein kinase activation in endometrium with polycystic ovary syndrome and its significance].

OBJECTIVE: to investigate the activation of mitogen-activated protein kinase (MAPK)/extracellular signal-regulated protein kinase (ERK) signaling pathway in the endometrium of women with polycystic ovary syndrome (PCOS) and its effect and significance in the cause of hyperplasia and carcinoma; and investigate the factors which affect the activation of the MAPK/ERK signaling pathway. METHODS: collected 52 patients diagnosed as PCOS who were taken dilation and curettage of uterus as study, while 32 non-PCOS patients matched as control group. Serum hormonal parameters, fasting blood glucose and insulin were measured in all patients. The PCOS patients were sub-group as insulin resistance group and non-insulin resistance group; all the patients were carried out pathology inspection of endometria, and the PCOS patients were sub-group as endometrial hyperplasia and carcinoma group and normal endometrium group based on the outcome of pathology inspection. Western blot were performed to detect the expressions of ERK1/2 and phosphorylated ERK1/2 (p-ERK1/2), the activation of ERK1/2. RESULTS: (1) the expression of p-ERK1/2 [(61 ± 13)%] in the endometrium in PCOS group was higher than that in the control [(44 ± 10)%, P < 0.01]. (2) The expression of p-ERK1/2 was significantly increased in group of endometrial hyperplasia and carcinoma [(70 ± 11)%] compared to that in group of normal endometrium [(55 ± 10)%, P < 0.01], while there were significant difference between group of insulin resistance [(63 ± 13)%] and group of non-insulin resistance [(55 ± 7)%, P < 0.01]. (3)Fasting insulin level, insulin area under the curve and body mass index were related to the expression of p-ERK1/2 in endometrium with PCOS, the correlation coefficient were 0.447, 0.456 and 0.381, respectively (all P < 0.01). CONCLUSIONS: the MAPK/ERK signaling pathway in endometrium with PCOS was overactivation, which was related to the endometrial hyperplasia and carcinoma; while the activation of MAPK/ERK signaling pathway were effected by insulin resistance and hyperinsulinemia.

Malignant transformation of non-neoplastic Barrett's epithelial cells through well-defined genetic manipulations.

BACKGROUND: Human Barrett's cancer cell lines have numerous, poorly-characterized genetic abnormalities and, consequently, those lines have limited utility as models for studying the early molecular events in carcinogenesis. Cell lines with well-defined genetic lesions that recapitulate various stages of neoplastic progression in Barrett's esophagus would be most useful for such studies. METHODOLOGY/PRINCIPAL FINDINGS: To develop such model cell lines, we started with telomerase-immortalized, non-neoplastic Barrett's epithelial (BAR-T) cells, which are spontaneously deficient in p16, and proceeded to knock down p53 using RNAi, to activate Ras by introducing oncogenic H-Ras(G12V), or both. BAR-T cells infected with either p53 RNAi or oncogenic H-Ras(G12V) alone maintained cell-to-cell contact inhibition and did not exhibit anchorage-independent growth in soft agar. In contrast, the combination of p53 RNAi knockdown with expression of oncogenic H-Ras(G12V) transformed the p16-deficient BAR-T cells, as evidenced by their loss of contact inhibition, by their formation of colonies in soft agar, and by their generation of tumors in immunodeficient mice. CONCLUSIONS/SIGNIFICANCE: Through these experiments, we have generated a number of transformed and non-transformed cell lines with well-characterized genetic abnormalities recapitulating various stages of carcinogenesis in Barrett's esophagus. These lines should be useful models for the study of carcinogenesis in Barrett's esophagus, and for testing the efficacy of chemopreventive and chemotherapeutic agents.

Acid and bile salt-induced CDX2 expression differs in esophageal squamous cells from patients with and without Barrett's esophagus.

BACKGROUND & AIMS: It is not clear why only a minority of patients with gastroesophageal reflux disease (GERD) develop Barrett's esophagus. We hypothesized that differences among individuals in molecular pathways activated when esophageal squamous epithelium is exposed to reflux underlie the development of Barrett's metaplasia. METHODS: We used esophageal squamous cell lines from patients who had GERD with Barrett's esophagus (normal esophageal squamous [NES]-B3T and NES-B10T) and without Barrett's esophagus (NES-G2T and NES-G4T) to study effects of acid and bile salts on expression of the CDX2 gene. Bay 11-705, Ad5 inhibitor kappaB(IkappaB)alpha-SR, and site-directed mutagenesis were used to explore effects of nuclear factor-kappaB (NF-kappaB) inhibition on CDX2 promoter activity; DNA binding of the NF-kappaB subunits p50 and p65 was assessed by chromatin immune-precipitation. RESULTS: Acid and bile salts increased CDX2 messenger RNA (mRNA), protein, and promoter activity in NES-B3T and NES-B10T cells, but not in NES-G2T or NES-G4T cells. Inhibition of NF-kappaB abolished the increase in CDX2 promoter activity. Increased CDX2 promoter activity was associated with nuclear translocation of p50, which bound to the promoter. We found CDX2 mRNA in 7 of 10 esophageal squamous biopsy specimens from patients with Barrett's esophagus, but in only 1 of 10 such specimens from patients who had GERD without Barrett's esophagus. CONCLUSIONS: Acid and bile salts induce CDX2 mRNA and protein expression in esophageal squamous cells from patients with Barrett's esophagus, but not from GERD patients without Barrett's esophagus. We speculate that these differences in acid- and bile salt-induced activation of molecular pathways may underlie the development of Barrett's metaplasia.

In benign Barrett's epithelial cells, acid exposure generates reactive oxygen species that cause DNA double-strand breaks.

Cells that sustain double-strand breaks (DSB) can develop genomic instability, which contributes to carcinogenesis, and agents that cause DSBs are considered potential carcinogens. We looked for evidence of acid-induced DNA damage, including DSBs, in benign Barrett's epithelial (BAR-T) cell lines in vitro and in patients with Barrett's esophagus in vivo. In BAR-T cells, we also explored the mechanisms underlying acid-induced DNA damage. We exposed BAR-T cells to acid in the presence of a fluorescent probe for reactive oxygen species (ROS) and in the presence or absence of disodium 4,4'-diisothiocyanatostilbene-2,2'-disulfonate (which prevents intracellular acidification) and N-acety-l-cysteine (a scavenger of ROS). DSBs were detected by Western blotting and immunofluorescence for histone H2AX phosphorylation and by CometAssay. During endoscopy in patients with Barrett's esophagus, we took biopsy specimens from the metaplastic mucosa before and after esophageal perfusion with 0.1 N HCl for 3 min and sought DSBs by Western blotting for histone H2AX phosphorylation. In BAR-T cells, acid exposure resulted in ROS production and caused a time-dependent increase in levels of phospho-H2AX that continued for at least 48 h. Pretreatment with disodium 4,4'-diisothiocyanatostilbene-2,2'-disulfonate or N-acety-l-cysteine prevented the acid-induced increase in phospho-H2AX levels. DSBs also were detected in biopsy specimens of Barrett's metaplasia following esophageal acid perfusion in all of 6 patients with Barrett's esophagus. Acid exposure causes DSBs in Barrett's epithelial cells through ROS produced as a consequence of intracellular acidification. These findings suggest that acid can be considered a carcinogen in Barrett's esophagus.

Gastroesophageal reflux might cause esophagitis through a cytokine-mediated mechanism rather than caustic acid injury.

BACKGROUND & AIMS: Reflux esophagitis is believed to be caused by the caustic effects of refluxed gastric acid on esophageal epithelial cells. However, caustic chemical injuries develop rapidly whereas esophagitis might not appear until weeks after the induction of reflux in animal models. We studied early histologic events in the development of reflux esophagitis in a rat model and performed in vitro experiments to determine whether exposure to acidified bile salts causes esophageal epithelial cells to secrete chemokines that might contribute to inflammation. METHODS: At various time points after esophagoduodenostomy, the rat esophagus was removed and inflammatory changes were analyzed by histologic analyses. Human esophageal squamous cell lines were exposed to acidified bile salts to evaluate their effects on cytokine production and immune-cell migration. RESULTS: Reflux esophagitis started at postoperative day 3 with lymphocytic infiltration of the submucosa that progressed to the epithelial surface-these findings contradicted those expected from a caustic chemical injury. Basal cell and papillary hyperplasia preceded the development of surface erosions. Exposure of squamous cells to acidified bile salts significantly increased the secretion of interleukin-8 and interleukin-1beta; conditioned media from these cells caused significant increases in the migration rates of T cells and neutrophils. CONCLUSIONS: These findings support, but do not prove, an alternative concept for the development of reflux esophagitis in which refluxed gastric juice does not directly damage the esophagus, but rather stimulates esophageal epithelial cells to secrete chemokines that mediate damage of esophageal tissue.

Unlike esophageal squamous cells, Barrett's epithelial cells resist apoptosis by activating the nuclear factor-kappaB pathway.

Apoptosis is an important mechanism for maintaining tissue homeostasis and for preventing the proliferation of cells with mutations that could result in malignancy. Barrett's epithelium has been reported to be more resistant to apoptosis than normal esophageal squamous epithelium. We have explored the contribution of the nuclear factor-kappaB (NF-kappaB) pathway to apoptotic resistance in non-neoplastic, telomerase-immortalized esophageal squamous (NES) and Barrett's (BAR-T) epithelial cell lines. We exposed these cells to UV-B irradiation in doses known to cause DNA damage and to induce apoptosis in normal cells, and studied apoptosis as well as the expression of phospho-H2AX, NF-kappaB, Bcl-2, XIAP, cIAP-1, and survivin proteins. We also used Bay 11-7085 and siRNAs to NF-kappaB and Bcl-2 to assess the effects of NF-kappaB and Bcl2 inhibition on apoptosis. UV-B irradiation at low doses (50 and 100 J/m(2)) caused DNA damage in both NES and BAR-T cells but significantly increased apoptosis only in NES cells. UV-B irradiation caused a decrease in the levels of NF-kappaB, Bcl-2, cIAP-1, XIAP, and survivin in NES cells but increased the levels of those proteins in BAR-T cells. The resistance of BAR-T cells to apoptosis induced by low-dose UV-B irradiation was abolished by Bay 11-7085 and by siRNA for NF-kappaB and was decreased significantly by siRNA for Bcl-2. We conclude that the ability of Barrett's epithelial cells to activate the NF-kappaB pathway when they have sustained DNA damage allows them to resist apoptosis. This capacity to avoid apoptosis despite genotoxic damage may underlie the persistence and malignant predisposition of Barrett's metaplasia.

Esophageal adenocarcinoma arising in Barrett esophagus.

The major risk factors for esophageal adenocarcinoma are gastroesophageal reflux disease (GERD) and Barrett esophagus, a squamous-to-columnar cell metaplasia that predisposes to malignancy. Adenocarcinomas in Barrett esophagus are thought to arise through a sequence of growth-promoting, genetic alterations that accumulate until the cells have acquired the physiologic hallmarks of cancer proposed by Hanahan and Weinberg. Moreover, GERD and Barrett esophagus are associated with chronic esophagitis, and inflammation is a well known risk factor for cancer formation. The cell that gives rise to Barrett metaplasia is not known. It has been proposed that the metaplasia may arise from a change in the differentiation pattern of stem cells that either reside in the esophagus or are recruited to the esophagus from the bone marrow. Alternatively, it is possible that Barrett metaplasia develops through the conversion of one differentiated cell type into another. Regardless of the cell of origin, Barrett metaplasia ultimately must be sustained by stem cells, which might be identified by intestinal stem cell markers. An emerging concept in tumor biology is that cancer stem cells are responsible for sustaining tumor growth. If Barrett cancers develop from Barrett stem cells, then a therapy targeted at those stem cells might prevent esophageal adenocarcinoma. This report reviews the risk factors for Barrett esophagus and esophageal adenocarcinoma, the mechanisms by which genetic alterations might contribute to carcinogenesis in Barrett esophagus, and the role of stem cells in the development of Barrett metaplasia and adenocarcinoma.