Dong-Won Ahn

Anti-gastric cancer effects of celecoxib, a selective COX-2 inhibitor, through inhibition of Akt signaling.

Background and Aim:  Previously, we showed that treatment with celecoxib significantly reduced the number of viable gastric cancer cells, in a dose‐ and time‐dependent manner. However, the specific anti‐cancer effects of celecoxib on gastric cancer cells have not been clarified. The present in vitro study was carried out to investigate the mechanism involved in the anti‐gastric cancer effects of celecoxib.

Hemostatic efficacy and clinical outcome of endoscopic treatment of Dieulafoy's lesions: comparison of endoscopic hemoclip placement and endoscopic band ligation

BACKGROUND The most suitable mechanical endoscopic hemostasis for a bleeding Dieulafoys lesion (DL) is not yet well established. OBJECTIVE To compare the hemostatic efficacy and clinical outcome of endoscopic hemoclip placement (EHP) and endoscopic band ligation (EBL). DESIGN Retrospective, single-center study. SETTING A tertiary-care referral university hospital. PATIENTS Sixty-six patients who received mechanical endoscopic hemostasis for bleeding DLs. INTERVENTIONS Endoscopic hemostasis. MAIN OUTCOME MEASUREMENT Primary hemostasis and rebleeding rates. RESULTS DLs accounted for 3.8% of cases of acute nonvariceal upper GI bleeding during the study period. Active bleeding from DLs was noted in 34 patients (51.5%). EHP and EBL were performed as a method of endoscopic hemostasis in 34 and 32 patients, respectively. There were no significant differences between the 2 groups with respect to baseline characteristics (except comorbidities) and endoscopic features of DLs. Primary hemostasis was achieved in all 66 patients (100%). There were 6 cases of recurrent bleeding: 5 (14.7%) and 1 (3.1%) in the EHP and EBL groups, respectively. Secondary hemostasis was achieved with endoscopic treatment and angiographic embolization in 5 patients and 1 patient, respectively, and no patients required surgery. The mean procedure time of endoscopic hemostasis was significantly longer in the EHP group (19.1 vs 11.5 minutes, P = .015). There was no bleeding-related mortality. LIMITATIONS Retrospective analysis. CONCLUSIONS Both EHP and EBL are suitable for the treatment of bleeding DLs. EBL can be used as an initial hemostatic method for bleeding DLs because of a favorable clinical outcome comparable to that with EHP and a shorter procedure time.

Enhanced antitumor effect of combination therapy with gemcitabine and guggulsterone in pancreatic cancer.

Objectives Guggulsterone is a dietary plant sterone possessing therapeutic potential against cancers. However, the antitumor effect of this natural compound on pancreatic cancer has not been determined yet. This study was designed to investigate the therapeutic efficacy of guggulsterone in pancreatic cancer. Methods In this study, we examined the effect of guggulsterone on cell proliferation and apoptosis in pancreatic cancer cell lines, and then, we investigated the mechanisms responsible for the effect of guggulsterone. Finally, we investigated whether the combination of guggulsterone and gemcitabine had an additional therapeutic effect compared to gemcitabine single regimen in pancreatic cancer cell lines (in vitro) and in a xenograft model using nude mice (in vivo). Results In vitro, the combination treatment resulted in more growth inhibition and apoptosis through the down-regulation of nuclear factor &kgr;B activity with suppression of Akt and BcL-2 and through the activation of c-Jun NH2-terminal kinase and Bax in pancreatic cancer cell lines. In vivo, the combination therapy augmented tumor growth inhibition through the same mechanisms in tumor tissue. Conclusions The combination of guggulsterone to gemcitabine enhanced antitumor efficacy through apoptosis induction by suppressing Akt and nuclear factor &kgr;B activity and by modulating apoptosis-related protein expression in pancreatic cancer.

Biliary drainage for obstructive jaundice caused by unresectable hepatocellular carcinoma: the endoscopic versus percutaneous approach.

BACKGROUND For palliative treatment of the obstructive jaundice associated with unresectable hepatocellular carcinoma (HCC), percutaneous transhepatic biliary drainage (PTBD) or endoscopic retrograde biliary drainage (ERBD) has been performed. PTBD is preferred as an initial procedure. Little is known about the better option for patients with obstructive jaundice caused by unresectable HCC. METHODS Sixty patients who had received ERBD or PTBD for the palliative treatment of obstructive jaundice caused by unresectable HCC between January 2006 and May 2010 were included in this retrospective study. Successful drainage, drainage patency, and the overall survival of patients were evaluated. RESULTS Univariate analysis revealed that the overall frequency of successful drainage was higher in the ERBD group (22/29, 75.9%) than in the PTBD group (15/31, 48.4%) (P=0.029); but multivariate analysis showed marginal significance (P=0.057). The duration of drainage patency was longer in the ERBD group than in the PTBD group (82 vs 37 days, respectively, P=0.020). Regardless of what procedure was performed, the median survival time of patients who had a successful drainage was much longer than that of the patients who did not have a successful drainage (143 vs 38 days, respectively, P<0.001). CONCLUSION Besides PTBD, ERBD may be used as the initial treatment option to improve obstructive jaundice in patients with unresectable HCC if there is a longer duration of drainage patency after a successful drainage.

Treatment and clinical outcome of needle-track seeding from hepatocellular carcinoma

Background/Aims Needle-track seeding is a rare but important complication of diagnostic and therapeutic ultrasound (US)-guided procedures in hepatocellular carcinoma (HCC). We examined the frequency of needle-track seeding after US-guided percutaneous ethanol injection (PEI), fine-needle aspiration biopsy (FNAB), and percutaneous transhepatic biliary drainage (PTBD) in order to determine the appropriate treatment for needle-track seeding and its clinical outcome. Methods We analyzed the clinical characteristics and treatment outcomes in eight patients who experienced needle-track seeding from HCC after an US-guided procedure (FNAB, PEI, or PTBD) between January 1990 and July 2004. Results Seven (0.14%) of 5,092 patients who experienced needle-track seeding (2 after PEI, 4 after FNAB, and 1 after PTBD) during the study period and 1 other patient who experienced needle-track seeding recently were recruited for this study. Two of the eight patients underwent mass excision and the other six patients underwent en-bloc wide excision for the needle-track seeding. Tumors recurred in the needle-tracks in both patients who underwent mass excision but not in the six patients who underwent en-bloc wide excision. Mortality occurred in three patients who experienced the recurrence and progression of intrahepatic HCC. Conclusions The incidence of needle-track seeding after US-guided procedures in HCC was 0.14%. En-bloc wide excision seems to be the optimal treatment for minimizing the probability of tumor recurrence due to needle-track seeding.

Palliative treatment of unresectable hepatocellular carcinoma with obstructive jaundice using biliary drainage with subsequent transarterial chemoembolization.

BACKGROUND Nonsurgical biliary drainage is considered as a priority for obstructive jaundice associated with unresectable hepatocellular carcinoma (HCC). Successful drainage allows the patient to receive antitumor therapy, such as transarterial chemoembolization (TACE). However, only limited data are available on clinical outcomes in patients who treated biliary drainage with subsequent TACE. OBJECTIVE This study evaluated the clinical outcome of biliary drainage with subsequent TACE in unresectable HCC patients with obstructive jaundice. DESIGN This was a retrospective study. SETTING/SUBJECTS A total of 60 patients received endoscopic biliary drainage (ERBD) or percutaneous transhepatic biliary drainage (PTBD) in two tertiary care referral centers. MEASUREMENTS Successful drainage and survival were measured. RESULTS Successful drainage was achieved in 39 (65%) patients. The median survival of 39 patients in whom successful drainage was achieved, regardless of which procedure was performed, was much longer than that of 21 patients without successful drainage (147 days versus 38 days, respectively, P<.001). In particular, the median survival was longer in 17 patients who underwent TACE after achieving successful drainage than in 22 patients who were treated conservatively after achieving successful drainage (410 days versus 77 days, respectively, P<.001). Multivariable analysis in 39 patients in the successful drainage group showed that TACE (hazard ratio 0.15; 95% confidence interval 0.05-0.45, P=.001) was an independent predictive factor of a favorable outcome. CONCLUSIONS Effective palliation by successful biliary drainage with subsequent TACE might prolong the survival in patients with obstructive jaundice caused by unresectable HCC.

Older Adults with Biliary Tract Cancer: Treatment and Prognosis

To compare survival in older (≥65) and younger (<65) individuals with biliary tract cancer (BTC) and to determine whether treatment efficacy varies according to age.

Results of repeat endoscopic retrograde cholangiopancreatography after initial biliary cannulation failure following needle-knife sphincterotomy.

Background and Aim:  After failed biliary cannulation with needle knife sphincterotomy (NKS), endoscopic retrograde cholangiopancreatography (ERCP) is sometimes repeatedly performed in clinically stable patients; however, there are few reports about the results. This study assessed the results of repeated ERCPs after failure with NKS.

Inflexinol reduces severity of acute pancreatitis by inhibiting nuclear factor-κB activation in cerulein-induced pancreatitis.

Objectives To examine the effect of inflexinol on the development of acute pancreatitis (AP) and to investigate the mechanisms responsible for the protective effect against AP. Methods Acute pancreatitis was induced in mice by intraperitoneal injection of cerulein. Inflexinol was administered intraperitoneally 4 times every 6 hours from 1 hour before the first cerulein injection. Serum amylase activity and histology of the pancreas were measured. Determination of pancreatic nuclear factor-&kgr;B (NF-&kgr;B) p65 expression was conducted by Western blotting and immunohistochemistry to investigate the mechanisms responsible for the inflexinol effects. Results Serum amylase activity in the cerulein group was significantly higher than that in the control group (P < 0.05). Pancreatic histology revealed marked inflammatory changes in the cerulein group such as interstitial edema, vacuolization, necrosis, and infiltration of inflammatory cells; and Western blotting and immunohistochemistry showed marked NF-&kgr;B p65 expression. Treatment with inflexinol significantly attenuated the inflammatory changes in pancreatic histology at 24, 48, and 72 hours (P < 0.05). Pancreatic NF-&kgr;B p65 expression decreased significantly after inflexinol treatment (P < 0.05). Conclusion Inflexinol reduced the severity of cerulein-induced AP by inhibiting NF-&kgr;B activation.

Clinical outcome of acute nonvariceal upper gastrointestinal bleeding after hours: the role of urgent endoscopy.

Background/Aims: This study was performed to investigate the clinical role of urgent esophagogastroduodenoscopy (EGD) for acute nonvariceal upper gastrointestinal bleeding (ANVUGIB) performed by experienced endoscopists after hours. Methods: A retrospective analysis was performed for consecutively collected data of patients with ANVUGIB between January 2009 and December 2010. Results: A total of 158 patients visited the emergency unit for ANVUGIB after hours. Among them, 60 underwent urgent EGD (within 8 hours) and 98 underwent early EGD (8 to 24 hours) by experienced endoscopists. The frequencies of hemodynamic instability, fresh blood aspirate on the nasogastric tube, and high-risk endoscopic findings were significantly higher in the urgent EGD group. Primary hemostasis was achieved in all except two patients. There were nine cases of recurrent bleeding, and 30-day mortality occurred in three patients. There were no significant differences between the two groups in primary hemostasis, recurrent bleeding, and 30-day mortality. In a multiple linear regression analysis, urgent EGD significantly reduced the hospital stay compared with early EGD. In patients with a high clinical Rockall score (more than 3), urgent EGD tended to decrease the hospital stay, although this was not statistically significant (7.7 days vs. 12.0 days, p > 0.05). Conclusions: Urgent EGD after hours by experienced endoscopists had an excellent endoscopic success rate. However, clinical outcomes were not significantly different between the urgent and early EGD groups.