Yiqi Du

Combination of plasma microRNAs with serum CA19-9 for early detection of pancreatic cancer

This study was performed to identify plasma microRNAs (miRNAs) as diagnostic biomarkers for pancreatic cancer (PCa) and to assess their supplementary role with serum CA19‐9 in early identification of tumors. Plasma RNAs were extracted from 140 PCa patients, 111 chronic pancreatitis (CP) patients and 68 normal controls, and the relative abundances of seven miRNAs (miR‐16, 21, 155, 181a, 181b, 196a and 210) were measured using real‐time PCR. Their diagnostic utility for PCa and correlation with clinical characteristics were analyzed. All seven miRNAs were significantly aberrantly upregulated in the PCa group compared with both the CP and normal groups, between which only four miRNAs (miR‐155, 181a, 181b and 196a) were significantly different. Logistic modeling proved that only miR‐16 and miR‐196a possessed an independent role in discriminating PCa from normal and CP. Furthermore, after including serum CA19‐9 in the logistic model, the combination of miR‐16, miR‐196a and CA19‐9 was more effective for discriminating PCa from non‐PCa (normal+CP) (AUC‐ROC, 0.979; sensitivity, 92.0%; specificity, 95.6%), and for discriminating PCa from CP (AUC‐ROC, 0.956; sensitivity, 88.4%; specificity, 96.3%) compared with the miRNA panel (miR‐16+miR‐196a) or CA19‐9 alone. Most significantly, the combination was effective at identification of tumors in Stage 1 (85.2%). In conclusion, plasma miRNAs were effective for distinguishing PCa from non‐PCa (normal+CP). The combination of miR‐16, miR‐196a and CA19‐9 was more effective for PCa diagnosis, especially in early tumor screening.

Assessment of morbidity and mortality associated with EUS-guided FNA: a systematic review

BACKGROUND EUS-guided FNA (EUS-FNA) permits both morphologic and cytologic analysis of lesions within or adjacent to the GI tract. Although previous studies have evaluated the accuracy of EUS-FNA, little is known about the complications of EUS-FNA. Moreover, the frequency and severity of complications may vary from center to center and may be related to differences in individual experience. OBJECTIVE To systematically review the morbidity and mortality associated with EUS-FNA. DESIGN MEDLINE and EMBASE were searched to identify relevant English-language articles. MAIN OUTCOME MEASUREMENTS EUS-FNA-specific morbidity and mortality rates. RESULTS We identified 51 articles with a total of 10,941 patients who met our inclusion and exclusion criteria; the overall rate of EUS-FNA-specific morbidity was 0.98% (107/10,941). In the small proportion of patients with complications of any kind, the rates of pancreatitis (36/8246; 0.44%) and postprocedure pain (37/10,941; 0.34%) were 33.64% (36/107) and 34.58% (37/107), respectively. The mortality rate attributable to EUS-FNA-specific morbidity was 0.02% (2/10,941). Subgroup analysis showed that the morbidity rate was 2.44% in prospective studies compared with 0.35% in retrospective studies for pancreatic mass lesions (P=.000), whereas it was 2.33% versus 5.07% for pancreatic cysts (P=.036). LIMITATIONS Few articles reported well-designed, prospective studies and few focused on overall complications after EUS-FNA. CONCLUSIONS EUS-FNA-related morbidity and mortality rates are relatively low, and most associated events are mild to moderate in severity.

Body Mass Index Increases Risk for Colorectal Adenomas Based on Meta-analysis

BACKGROUND & AIMS There have been inconsistent results published about the relationship between excess body weight, expressed as increased body mass index (BMI), and risk of colorectal adenoma (CRA). We conducted a meta-analysis to explore this relationship. We focused on whether the relationship varied based on the sex of the study subjects, study design, features of the polyps, or potential confounders, including alcohol use, nonsteroidal anti-inflammatory drug use, smoking, and exercise. METHODS We identified studies by performing a literature search of Medline, EMBASE, and ISI Web of Science through July 31, 2011, and by searching the reference lists of pertinent articles. We analyzed 36 independent studies, which included 29,860 incident cases of CRA. Summary relative risks with their 95% confidence intervals (CIs) were calculated with a random-effects model. Between-study heterogeneity was assessed using Cochrans Q statistic and I(2) analyses. RESULTS Overall, a 5-unit increase in BMI (calculated as kg/m(2)) increased the risk for CRA (summary relative risk = 1.19; 95% CI: 1.13-1.26), although there was a high level of heterogeneity among studies (P(heterogeneity) < .001; I(2) = 76.8%). Subgroup analyses revealed that the increased risk of CRA in obese individuals was independent of race, geographic location, study design, sex, adenoma progression, and confounders. The association between increased BMI and risk for CRA was stronger for colon than rectal adenoma. CONCLUSIONS Based on a meta-analysis, increased BMI increases the risk for colon but not rectal adenoma. Unlike colorectal cancer, there is no sex difference in the relationship between increased BMI and risk of CRA.

Adjuvant probiotics improve the eradication effect of triple therapy for Helicobacter pylori infection

AIM To investigate whether the addition of probiotics can improve the eradication effect of triple therapy for Helicobacter pylori (H. pylori) infection. METHODS This open randomized trial recruited 234 H. pylori positive gastritis patients from seven local centers. The patients were randomized to one-week standard triple therapy (omeprazole 20 mg bid, clarithromycin 500 mg bid, and amoxicillin 1000 mg bid; OCA group, n = 79); two weeks of pre-treatment with probiotics, containing 3 × 10(7)Lactobacillus acidophilus per day, prior to one week of triple therapy (POCA group, n = 78); or one week of triple therapy followed by two weeks of the same probiotics (OCAP group, n = 77). Successful eradication was defined as a negative C13 or C14 urease breath test four weeks after triple therapy. Patients were asked to report associated symptoms at baseline and during follow-up, and side effects related to therapy were recorded. Data were analyzed by both intention-to-treat (ITT) and per-protocol (PP) methods. RESULTS PP analysis involved 228 patients, 78 in the OCA, 76 in the POCA and 74 in the OCAP group. Successful eradication was observed in 171 patients; by PP analysis, the eradication rates were significantly higher (P = 0.007 each) in the POCA (62/76; 81.6%, 95% CI 72.8%-90.4%) and OCAP (61/74; 82.4%, 95% CI 73.6%-91.2%) groups than in the OCA group (48/78; 61.5%, 95% CI 50.6%-72.4%). ITT analysis also showed that eradication rates were significantly higher in the POCA (62/78; 79.5%, 95% CI 70.4%-88.6%) and OCAP (61/77; 79.2%, 95% CI 70%-88.4%) groups than in the OCA group (48/79; 60.8%, 95% CI 49.9%-71.7%), (P = 0.014 and P = 0.015). The symptom relieving rates in the POCA, OCAP and OCA groups were 85.5%, 89.2% and 87.2%, respectively. Only one of the 228 patients experienced an adverse reaction. CONCLUSION Administration of probiotics before or after standard triple therapy may improve H. pylori eradication rates.

Alarm features and age for predicting upper gastrointestinal malignancy in Chinese patients with dyspepsia with high background prevalence of Helicobacter pylori infection and upper gastrointestinal malignancy: an endoscopic database review of 102 665 patients from 1996 to 2006

Objective Patients with dyspepsia with alarm features are suspected of having upper gastrointestinal (GI) malignancy; however, the true value of alarm features in predicting an underlying malignancy for patients with dyspepsia with high background prevalence of Helicobacter pylori infection and upper GI malignancy is uncertain. The aim of the present study was to determine the diagnostic accuracy of alarm features in predicting upper GI malignancy by reviewing an endoscopic database consisting of >100 000 Chinese patients. Methods A retrospective analysis of prospectively collected data was conducted in a single tertiary medical centre. Consecutive patients who underwent oesophagogastroduodenoscopy (OGD) for dyspepsia in 1996–2006 were enrolled. The data including gender, age, symptoms, and endoscopic and pathological findings were analysed. The main outcome measure was the diagnostic accuracy of individual alarm feature. Results 102 665 patients were included in the final analysis. Among all the 4362 patients with malignancy, 52% (2258/4362) had alarm features. Among 15 235 patients who had alarm features, 2258 (14.8%) were found to have upper GI malignancy. The pooled sensitivity and specificity of the alarm features were 13.4% and 96.6%, respectively. Only the feature of dysphagia in patients between 36 and 74 years old had a positive likelihood ratio (PLR) >10 for malignancy prediction, while all other alarm features in other age groups had a PLR <10. Conclusions For uninvestigated Chinese patients with dyspepsia with high background prevalence of H pylori infection and upper GI malignancy, alarm features and age, except for dysphagia in patients between 36 and 74 years old, had limited predictive value for a potential malignancy; therefore, prompt endoscopy may be recommended for these patients. However, less invasive, inexpensive screening methods with high diagnostic yield are still needed to reduce unnecessary endoscopy workload.

Down-regulation of MicroRNA-494 via Loss of SMAD4 Increases FOXM1 and β-Catenin Signaling in Pancreatic Ductal Adenocarcinoma Cells

BACKGROUND & AIMS Dysregulation of β-catenin and the transcriptional activator FOXM1 mediate oncogenesis, but it is not clear how these proteins become dysregulated in tumors that do not typically carry mutations in adenomatous polyposis coli (APC) or β-catenin, such as pancreatic ductal adenocarcinomas (PDACs). We searched for microRNAs that regulate levels of FOXM1 in PDAC cells and samples from patients. METHODS We identified microRNAs that affect levels of FOXM1 in PDACs using bioinformatic, genetic, and pharmacologic approaches. We altered expression of the microRNA-494 (miR-494) in PDAC cell lines (AsPC-1 and PANC-1) and examined the effects on FOXM1 and β-catenin signaling and cell proliferation and colony formation. The cells were injected into immunocompromised mice and growth of xenograft tumors and liver metastases were measured. We performed immunohistochemical analyses of 10 paired PDAC and nontumor pancreatic tissue samples collected from untreated patients during surgery. RESULTS We identified miR-494 as a negative regulator of FOXM1 levels in PDAC cells, and found that levels of this microRNA were reduced in PDAC specimens, compared with nontumor tissues. Loss of response of PDAC cells to transforming growth factor β, owing to SMAD4 deficiency, reduced expression of miR-494. Transgenic expression of miR-494 in PDAC cells produced the same effects as reducing expression of FOXM1 or blocking nuclear translocation of β-catenin, reducing cell proliferation, migration, and invasion, and increasing their sensitivity to gemcitabine. Reduced expression of miR-494 correlated with PDAC metastasis and reduced survival times of patients. CONCLUSIONS Loss of SMAD4 in PDAC cells leads to reduced levels of miR-494, increased levels of FOXM1, and nuclear localization of β-catenin. miR-494 might be developed as a prognostic marker for patients with PDAC or a therapeutic target.

Therapeutic strategies targeting cancer stem cells

Increasing studies have demonstrated a small proportion of cancer stem cells (CSCs) exist in the cancer cell population. CSCs have powerful self-renewal capacity and tumor-initiating ability and are resistant to chemotherapy and radiation. Conventional anticancer therapies kill the rapidly proliferating bulk cancer cells but spare the relatively quiescent CSCs, which cause cancer recurrence. So it is necessary to develop therapeutic strategies acting specifically on CSCs. In recent years, studies have shown that therapeutic agents such as metformin, salinomycin, DECA-14, rapamycin, oncostatin M (OSM), some natural compounds, oncolytic viruses, microRNAs, cell signaling pathway inhibitors, TNF-related apoptosis inducing ligand (TRAIL), interferon (IFN), telomerase inhibitors, all-trans retinoic acid (ATRA) and monoclonal antibodies can suppress the self-renewal of CSCs in vitro and in vivo. A combination of these agents and conventional chemotherapy drugs can significantly inhibit tumor growth, metastasis and recurrence. These strategies targeting CSCs may bring new hopes to cancer therapy.

Methylation of the SPARC gene promoter and its clinical implication in pancreatic cancer

BackgroundThe secreted protein acidic and rich in cysteine (SPARC) plays a pivotal role in regulating cell-matrix interactions and tumor angiogenesis, proliferation, and migration. Detection of SPARC gene methylation may be useful as a tumorigenesis marker for early detection of pancreatic cancer.MethodsMethylation of the SPARC gene transcriptional regulation region (TRR) was detected using bisulfite-specific (BSP) PCR-based sequencing analysis in 40 cases of pancreatic cancer and the adjacent normal tissues, 6 chronic pancreatitis tissues, and 6 normal pancreatic tissues. BSP cloning-based sequencing analysis was also performed in selected cases. Clinicopathological data from the cancer patients were collected and analyzed.ResultsAnalysis of SPARC gene TRR methylation showed two hypermethylation wave peak regions: CpG Region 1 (CpG site 1-7) and CpG Region 2 (CpG site 8-12). Pancreatic tissues have shown methylation in both regions with gradual increases from normal, chronic pancreatitis, and adjacent normal tissues to cancerous tissues. However, Methylation of CpG Region 2 was more sensitive than CpG Region 1 in pancreatic tumorigenesis. Furthermore, the methylation level of CpG Region 2 was associated with increased tumor size and exposure to the risk factors (tobacco smoke and alcohol consumption) for developing pancreatic cancer.ConclusionMethylation of the SPARC gene, specifically CpG Region 2, may be an early event during pancreatic tumorigenesis and should be further evaluated as a tumorigenesis marker for early detection of pancreatic cancer.

Aberrant expression miR-196a is associated with abnormal apoptosis, invasion, and proliferation of pancreatic cancer cells.

Objectives MiR-196a levels inversely correlated with survival in pancreatic adenocarcinoma patients. However, the functional contributions of miR-196a to pancreatic cancer remain unclear. Methods Three lentiviral vectors encoding microRNA miR-196a precursor, inhibitor, and scrambled microRNA oligomer were transfected into Panc-1 cells, respectively. Then we explored the regulation of inhibitor of growth 5 (ING5) expression by miR-196a and its impact on apoptosis, invasion, and growth of pancreatic cancer cells. The lentiviral transfected Panc-1 cells were surgically implanted into the pancreas of mice. In vivo tumor growth and ING5 expression were measured. Results Down-regulation of ING5 expression was detected in cells transfected with miR-196a precursor (P < 0.01), accompanied by less apoptosis, increased invasion, and proliferation compared with control cells (P < 0.05). Cells transfected with miR-196a inhibitor revealed an opposite trend. Smaller detectable tumors were found in only 60% of mice after implantation of Lenti.miR-196a inhibitor–transfected Panc-1 cells compared with controls (360.7 ± 303.6 mm3 vs 511.58 ± 365.9 mm3 in controls; P < 0.01). Conclusion Our results provide experimental evidence to support aberrant expression of miR-196a is associated with abnormal apoptosis, invasion, and proliferation of pancreatic cancer cells.

EUS-guided celiac ganglion irradiation with iodine-125 seeds for pain control in pancreatic carcinoma: a prospective pilot study

BACKGROUND Celiac plexus neurolysis for the palliative reduction of pain in unresectable pancreatic carcinoma (PC) is safe but provides limited relief. In a previous study, we found that EUS-guided implantation of iodine-125 ((125)I) around the celiac ganglia is a safe procedure and can induce apoptosis of local neurons in a porcine model. OBJECTIVE To evaluate the safety and efficacy of direct celiac ganglion irradiation with (125)I seeds for the relief of moderate to severe pain secondary to unresectable PC. DESIGN Prospective study. SETTING Single, tertiary care referral center. PATIENTS This study enrolled consecutive patients who had moderate to severe pain resulting from biopsy-proven unresectable PC. INTERVENTION All patients underwent EUS-guided direct celiac ganglion irradiation with (125)I seeds. Follow-up was conducted at least once weekly until death. MAIN OUTCOME MEASUREMENTS Blood parameters, Visual Analog Scale (VAS) score, mean analgesic (MS Contin [morphine sulfate]) consumption, and complications were evaluated during follow-up. RESULTS Twenty-three patients with unresectable PC underwent the procedure. The mean number of seeds implanted in the celiac ganglion per patient was 4 (range 2-6). Immediately after the procedure, pain relief and analgesic consumption showed no significant changes compared with preoperative values. Six patients (26%) reported pain exacerbation. Two weeks later, the VAS score and mean analgesic consumption were significantly less than preoperative values. No procedure-related deaths or major complications occurred. LIMITATIONS Uncontrolled study. CONCLUSIONS EUS-guided direct celiac ganglion irradiation with (125)I seeds can reduce the VAS score and analgesic drug consumption in patients with unresectable PC.