Curcumin Induces Cell Death in Esophageal Cancer Cells through Modulating Notch Signaling

Curcumin inhibits the growth of esophageal cancer cell lines; however, the mechanism of action is not well understood. It is becoming increasingly clear that aberrant activation of Notch signaling has been associated with the development of esophageal cancer. Here, we have determined that curcumin inhibits esophageal cancer growth via a mechanism mediated through the Notch signaling pathway.In this study, we show that curcumin treatment resulted in a dose and time dependent inhibition of proliferation and colony formation in esophageal cancer cell lines. Furthermore, curcumin treatment induced apoptosis through caspase 3 activation, confirmed by an increase in the ratio of Bax to Bcl2. Cell cycle analysis demonstrated that curcumin treatment induced cell death and down regulated cyclin D1 levels. Curcumin treatment also resulted in reduced number and size of esophagospheres. Furthermore, curcumin treatment led to reduced Notch-1 activation, expression of Jagged-1 and its downstream target Hes-1. This reduction in Notch-1 activation was determined to be due to the down-regulation of critical components of the γ-secretase complex proteins such as Presenilin 1 and Nicastrin. The combination of a known γ-secretase inhibitor DAPT and curcumin further decreased proliferation and induced apoptosis in esophageal cancer cells. Finally, curcumin treatment down-regulate the expressions of Notch-1 specific microRNAs miR-21 and miR-34a, and upregulated tumor suppressor let-7a miRNA.Curcumin is a potent inhibitor of esophageal cancer growth that targets the Notch-1 activating γ-secretase complex proteins. These data suggest that Notch signaling inhibition is a novel mechanism of action for curcumin during therapeutic intervention in esophageal cancers

Cost-effectiveness of routine mediastinoscopy in computed tomography– and positron emission tomography–screened patients with stage I lung cancer

ObjectiveAccurate preoperative staging is essential for the optimal management of patients with lung cancer. An important goal of preoperative staging is to identify mediastinal lymph node metastasis. Computed tomography and positron emission tomography may identify mediastinal lymph node metastasis with sufficient sensitivity to allow omission of mediastinoscopy. This study utilizes our experience with patients with clinical stage I lung cancer to perform a decision analysis addressing whether mediastinoscopy should be performed in clinical stage I lung cancer patients staged by computed tomography and positron emission tomography.MethodsWe retrospectively reviewed our thoracic surgery database for cases between May 1999 and May 2004. Patients deemed clinical stage I by computed tomography and positron emission tomography were chosen for further study. Individual computed tomography, positron emission tomography, and operative and pathology reports were reviewed. The postresection pathologic staging and long-term survival were recorded. A decision model was created using TreeAgePro software and our observed data for the prevalence of mediastinal lymph node metastases and for the rate of benign nodules. Data reported in the literature were also utilized to complete the decision analysis model. A sensitivity analysis of key variables was performed.ResultsA total of 248 patients with clinical stage I lung tumors were identified. One hundred seventy-eight patients (72%) underwent mediastinoscopy before resection, and 5/178 (3%) showed N2 disease. An additional 9 patients were found to have N2 metastasis in the final resected specimen, resulting in a total of 14/248 patients (5.6%) with occult mediastinal lymph node metastases. Benign nodules were found in 19/248 (8%) of patients. Decision analysis determined that mediastinoscopy added 0.008 years of life expectancy at a cost of $250,989 per life-year gained. The outcome was sensitive to the prevalence of N2 disease in the population and the benefit of induction versus adjuvant therapy for N2 lung cancer. If the prevalence of N2 disease exceeds 10$100,000 per life-year gained.ConclusionPatients with clinical stage I lung cancer staged by computed tomography and positron emission tomography benefit little from mediastinoscopy. The survival advantage it confers is very small and is dependent on the prevalence of N2 metastasis and the unproven superiority of induction therapy over adjuvant therapy

Large cell neuroendocrine carcinoma: An aggressive form of non-small cell lung cancer

ObjectiveLarge cell neuroendocrine carcinomas of the lung display morphologic and immunohistochemical characteristics common to neuroendocrine tumors and the morphologic features of large cell carcinomas. Surgical resection of large cell neuroendocrine carcinomas in many series has been described, with 5-year actuarial survivals ranging from 13% to 57%. Considerable debate has emerged as to whether these tumors should be classified and treated as non-small cell lung cancers or small cell lung cancers. The objective of this study was to report the outcome of surgical resection in patients with large cell neuroendocrine carcinomas.MethodsAn analysis of our tumor registry was performed to identify all patients undergoing surgical resection of lung cancer between July 1, 1988, and December 31, 2002, for large cell tumors. Cases were then segregated into large cell neuroendocrine carcinomas, mixed large cell neuroendocrine carcinomas (in which at least one portion of the tumor was a large cell neuroendocrine carcinoma), or large cell carcinomas on the basis of morphology and differentiation. Follow-up was complete on all patients, with a mean follow-up of 48 months. Type of resection, mortality, and survival by stage were analyzed. Kaplan-Meier survival was determined for all patients from the date of surgical intervention. Cox proportional hazards model analysis incorporating the variables of age, sex, histology, and stage estimated the effect of large cell neuroendocrine carcinomas and mixed large cell neuroendocrine carcinomas on recurrence and death. The stage of disease in all patients was assessed according to the 1997 American Joint Committee on Cancer guidelines.ResultsOf the 2099 patients who underwent resection, 82 (3.9%) had large cell lung cancers. Perioperative mortality was 2.4%. Overall survival and freedom from recurrence at 5 years for the entire group was 47.1% and 58.4%, respectively. Overall survival by histologic subtype at 5 years was 30.2% for patients with large cell neuroendocrine carcinomas (n = 45), 30.3% for patients with mixed large cell neuroendocrine carcinomas (n = 11), and 71.3% for patients with large cell carcinomas (n = 21). Survival was significantly worse for patients with large cell neuroendocrine carcinomas than for patients with large cell carcinomas (P = .013). The presence of large cell neuroendocrine carcinomas in the specimen (the large cell neuroendocrine carcinoma and mixed large cell neuroendocrine carcinoma groups combined) was significantly associated with decreased survival (relative risk, 2.44; 95% confidence interval 1.29–4.58; P = .003) and decreased freedom from recurrence (relative risk, 4.52; 95% confidence interval, 1.76–11.57; P < .001).ConclusionPatients with large cell neuroendocrine carcinomas have a significantly worse survival after resection than patients with large cell carcinomas, even in stage I disease. Accurate differentiation of large cell neuroendocrine carcinoma from large cell carcinoma is important because it identifies those patients at highest risk for the development of recurrent lung cancer

Down-regulation of beta catenin inhibits the growth of esophageal carcinoma cells

AbstractIntroductionEsophageal cancer remains a highly lethal malignancy, with therapeutic options of limited efficacy in the majority of patients. Understanding the molecular events involved in the pathogenesis of esophageal cancer offers insight into potential targets for treatment. Beta catenin and Wnt signaling abnormalities are involved in the development of both adenocarcinoma and squamous carcinoma of the esophagus. We hypothesized that down-regulation of beta catenin would inhibit the growth of human esophageal cancer.MethodsA human esophageal squamous cell carcinoma cell line (TE10) was treated with phosphorothioate antisense oligonucleotides to beta catenin. The cells were subsequently assayed for beta catenin mRNA and protein by real-time polymerase chain reaction and Western blot. Beta catenin transcriptional activity was determined by TOPFlash assay. Cell viability and growth was assessed by methyl-thiazol-diphenyl-tetrazolium assay and trypan blue exclusion. A colorimetric assay was employed to assess caspase 3 activity, and flow cytometry was done to determine percentage of cells in a given phase of the cell cycle.ResultsFollowing antisense treatment, beta catenin mRNA and protein concentration were decreased. There was corresponding decrease in beta catenin–transcription factor–dependent transcription. Treatment with beta catenin antisense resulted in significantly decreased cell viability and proliferation. The mechanism appears to be increased induction of apoptosis.ConclusionsThese data suggest a potential role for the targeting of beta catenin in the treatment of esophageal cancer

Anti-lipopolysaccharide monoclonal antibodies inhibit macrophage tnf messenger rna synthesis in vitro

Gram-negative bacterial lipopolysaccharide (LPS, endotoxin) directly stimulates macrophages to produce tumor necrosis factor (TNF). TNF, in turn, produces a constellation of adverse effects that includes hypotension, systemic acidosis, arterial hypoxemia, and death. Transcription of the TNF gene occurs within minutes of LPS stimulation and appears to be a critical control point in the synthesis and secretion of TNF protein by macrophages. We hypothesized that murine monoclonal antibody (mAb) 8G9 directed against Escherichia coli 0111:B4 LPS would provide protective capacity against an E. coli 0111:B4 bacterial challenge in vivo and would concurrently inhibit LPS-induced synthesis of TNF mRNA and secretion of TNF protein in vitro. E. coli 0111:B4 LPS was used to stimulate a macrophage-derived cell line (RAW 264.7) to produce TNF in the presence or absence of mAb 8G9. Media alone and LPS without 8G9 mAb served as controls against which the effect of 8G9 mAb was compared. Total cellular RNA was purified and analyzed by a Northern blotting technique utilizing a radiolabeled cDNA probe specific for TNF mRNA. TNF mRNA levels from each sample were quantitated by autoradiograph densitometry. Pretreatment with mAb 8G9 provided protective capacity against an intraperitoneal E. coli 0111:B4 bacterial challenge in vivo when compared with saline pretreatment alone (22% versus 90% mortality respectively, P \u3c 0.05). Preincubation of LPS with mAb 8G9 resulted in a significant inhibition of LPS-induced TNF mRNA synthesis (63 ± 20%, P \u3c 0.01) and TNF protein secretion (88 ± 10%, P \u3c 0.001) in vitro. We concluded that inhibition of LPS-induced TNF synthesis and secretion by mAb 8G9 is a key mechanism by which mAb 8G9 provides protection during gram-negative bacterial sepsis. © 1993 Academic Press. All rights reserved

Anti-lipopolysaccharide monoclonal antibodies inhibit macrophage tnf messenger rna synthesis in vitro

Gram-negative bacterial lipopolysaccharide (LPS, endotoxin) directly stimulates macrophages to produce tumor necrosis factor (TNF). TNF, in turn, produces a constellation of adverse effects that includes hypotension, systemic acidosis, arterial hypoxemia, and death. Transcription of the TNF gene occurs within minutes of LPS stimulation and appears to be a critical control point in the synthesis and secretion of TNF protein by macrophages. We hypothesized that murine monoclonal antibody (mAb) 8G9 directed against Escherichia coli 0111:B4 LPS would provide protective capacity against an E. coli 0111:B4 bacterial challenge in vivo and would concurrently inhibit LPS-induced synthesis of TNF mRNA and secretion of TNF protein in vitro. E. coli 0111:B4 LPS was used to stimulate a macrophage-derived cell line (RAW 264.7) to produce TNF in the presence or absence of mAb 8G9. Media alone and LPS without 8G9 mAb served as controls against which the effect of 8G9 mAb was compared. Total cellular RNA was purified and analyzed by a Northern blotting technique utilizing a radiolabeled cDNA probe specific for TNF mRNA. TNF mRNA levels from each sample were quantitated by autoradiograph densitometry. Pretreatment with mAb 8G9 provided protective capacity against an intraperitoneal E. coli 0111:B4 bacterial challenge in vivo when compared with saline pretreatment alone (22% versus 90% mortality respectively, P \u3c 0.05). Preincubation of LPS with mAb 8G9 resulted in a significant inhibition of LPS-induced TNF mRNA synthesis (63 ± 20%, P \u3c 0.01) and TNF protein secretion (88 ± 10%, P \u3c 0.001) in vitro. We concluded that inhibition of LPS-induced TNF synthesis and secretion by mAb 8G9 is a key mechanism by which mAb 8G9 provides protection during gram-negative bacterial sepsis. © 1993 Academic Press. All rights reserved

Curcumin treatment inhibits oncomiR miRNA in esophageal cancer cells.

<p>(A) real-time reverse transcription-PCR analysis of total miRNA from TE-7 cells following 30 µM of curcumin treatment for 24 h. Curcumin treatment significantly inhibit oncomiR miRNA expression in TE-7 cells (*<i>P</i><0.05). (B) Curcumin treatment significantly up-regulated tumor suppressor let-7a miRNA expression in TE-7 cells.</p

Curcumin inhibits esophageal cancer cell proliferation.

<p>(A) Curcumin inhibits proliferation of esophageal cancer cells. Cells were incubated with increasing doses of curcumin (0–50 µM) for up to 72 h and analyzed for cell proliferation. Curcumin treatment resulted in a significant dose- and time-dependent decrease in cell proliferation in all three cells when compared with untreated controls. (B) Curcumin inhibits colony formation. Esophageal cancer cells were incubated with 30 µM of curcumin for 24 h and allowed to grow into colonies for 10 days. Incubation with curcumin inhibits colony formation. Results are representative of three independent experiments. (C) Cyclin D1 is one the cell cycle regulatory protein and which is involved in the cell cycle arrest. RNA from TE-7 incubated with 30 µM curcumin was subjected to Real Time PCR for cyclin D1 mRNA expression. Curcumin treatment significantly inhibits cyclin D1 mRNA expression (*p<0.05). (D) Lysates from TE-7 incubated with 30 µM curcumin were analyzed by western blotting for cyclin D1 expression levels using mouse anti-cyclin D1 antibody. Curcumin treatment inhibits cyclin D1 protein expression.</p