Although this multicenter RCT was conducted in a strict setting, extended lymphadenectomy in radical PD did not benefit long-term survival in patients with resectable pancreatic head cancer and led to levels of morbidity, mortality and quality of life comparable to those found after standard lymphadenectomy.

Pancreatic cancer is the most lethal of all solid tumors partially because of its chemoresistance. Although gemcitabine is widely used as a first selected agent for the treatment of this disease despite low response rate, molecular mechanisms of gemcitabine resistance in pancreatic cancer still remain obscure. The aim of this study is to elucidate the mechanisms of gemcitabine resistance. The 81-fold gemcitabine resistant variant MiaPaCa2-RG was selected from pancreatic cancer cell line MiaPaCa2. By microarray analysis between MiaPaCa2 and MiaPaCa2-RG, 43 genes (0.04%) were altered expression of more than 2-fold. The most upregulated gene in MiaPaCa2-RG was ribonucleotide reductase M1 subunit (RRM1) with 4.5-fold up-regulation. Transfection with RRM1-specific RNAi suppressed more than 90% of RRM1 mRNA and protein expression. After RRM1-specific RNAi transfection, gemcitabine chemoresistance of MiaPaCa2-RG was reduced to the same level of MiaPaCa2. The 18 recurrent pancreatic cancer patients treated by gemcitabine were divided into 2 groups by RRM1 levels. There was a significant association between gemcitabine response and RRM1 expression (p 5 0.018). Patients with high RRM1 levels had poor survival after gemcitabine treatment than those with low RRM1 levels (p 5 0.016). RRM1 should be a key molecule in gemcitabine resistance in human pancreatic cancer through both in vitro and clinical models. RRM1 may have the potential as predictor and modulator of gemcitabine treatment. ' 2006 Wiley-Liss, Inc.Key words: gemcitabine; pancreatic cancer; drug resistance; RRM1; microarray Pancreatic cancer remains one of the most malignant cancers. Although surgery is the only curative treatment currently available, over 80% of patients have advanced regional disease or distant metastasis at the time of diagnosis and less than 20% of the patients are candidates for resection.1 Therefore, chemotherapy, radiation or a combination of these therapies most commonly plays an important role in pancreatic cancer treatment. They have not had a significant impact on survival rates in recent decades, however, despite many clinical trials.

The cancer drug gemcitabine (GEM) is a key drug for treating pancreatic ductal adenocarcinoma (PDAC), but PDAC cells develop chemoresistance after long-term administration. Since the tolerance was immediately spread to every PDAC tissue in a patient, it is assumed that some certain efficient mechanisms underlay in the development of chemoresistance. Changes in the levels of particular microRNAs or alterations in intercellular communication play a dominant role in chemoresistance development, and recent data also suggest that exosomes play an important role in this process. In this study, we revealed that the loop conferred chemoresistance in PDAC cells. The loop was as follows; 1, The long-term exposure of GEM increased miR-155 expression in PDAC cells. 2, The increase of miR-155 induced two different functions; exosome secretion and chemoresistance ability via facilitating the anti-apoptotic activity. 3, Exosome deliver the miR-155 into the other PDAC cells and induce the following function. The target therapy to miR-155 or the exosome secretion effectively attenuated the chemoresistance, and these results were validated with both clinical samples and in vivo experiments. This mechanism represents a novel therapeutic target in GEM treatment to PDAC.

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Background:We reported recently the clinical efficiency of interferon (IFN)-α/5-fluorouracil (5-FU) combination therapy in advanced hepatocellular carcinoma (HCC). However, prediction of the response to the combination therapy remains unsatisfactory. The aim of this study was to investigate the anti-tumour effects of microRNA (miR)-21 on the sensitivity of HCC cells to IFN-α/5-FU and whether miR-21 can be used as a predictor of the response to such therapy in HCC.Methods:Changes in the sensitivity of HCC cells (PLC/PRF/5 and HepG2) to IFN-α/5-FU were examined after transfection with pre-miR-21 or anti-miR-21. The correlation between miR-21 expression level, evaluated by qRT–PCR, and response to the therapy was also investigated in clinical HCC specimens.Results:Hepatocellular carcinoma cells transfected with pre-miR-21 were significantly resistant to IFN-α/5-FU. Annexin V assay showed that the percentage of apoptotic cells was significantly lower in cells transfected with pre-miR-21 than control cells. Transfection of anti-miR-21 rendered HCC cells sensitive to IFN-α/5-FU, and such sensitivity was weakened by transfection of siRNAs of target molecules, PETN and PDCD4. miR-21 expression in clinical HCC specimens was significantly associated with the clinical response to the IFN-α/5-FU combination therapy and survival rate.Conclusions:The miR-21 in HCC cell lines and clinical HCC samples is a significant modulator of the anti-tumour effect of IFN-α and 5-FU. This suggests that miR-21 is a potentially suitable marker for the prediction of the clinical response to the IFN-α/5-FU combination therapy.

The identification of molecular markers, useful for therapeutic decisions in pancreatic cancer patients, is crucial for advances in disease management. Gemcitabine, although a cornerstone of current therapy, has limited efficacy. RRM1 is a key molecule for gemcitabine efficacy and is also involved in tumor progression. We determined in situ RRM1 and excision repair cross complementation group 1 (ERCC1) protein levels in 68 pancreatic cancer patients. All had R0 resections without preoperative therapy. Protein levels were determined by automated quantitative analysis (AQUA), a fluorescence-based immunohistochemical method. The relationship between protein expressions and clinical outcomes, including response to gemcitabine at the time of disease recurrence, was determined. Patients with high RRM1 showed significantly better overall survival than patients with low expression (P=0.0196). There was a trend toward better overall survival for patient with high ERCC1 (P=0.0552). When both markers were considered together, patients with both high RRM1 and ERCC1 faired the best in terms of overall and disease-free survival (P=0.0066, P=0.0127). In addition, treatment benefit from gemcitabine in patients with disease recurrence was observed only in patients with low RRM1. The combination of RRM1 and ERCC1 expression is prognostic in pancreatic cancer patients after a complete resection. On disease recurrence, only patients with low RRM1 derive benefit from gemcitabine.

Our study showed that the expression of VEGF and Ang-2 correlated with MVD. Strong Ang-2 expression and/or high nuclear expression of HIF-1alpha is a significant predictive factor for recurrence after curative resection in HCC patients.

Background:We have previously demonstrated that long-term inhibition of Rho-kinase ameliorates pulmonary arterial hypertension (PAH) in animal models. In the present study, we examined the clinical effects of mid-term oral treatment with an extended release formulation of AT-877 (fasudil hydrochloride), a specific Rho-kinase inhibitor (AT-877ER) on PAH. Methods and Results:23 PAH patients were treated with either placebo (10/2 females/males, 51±16 years, idiopathic PAH (IPAH) in 6, PAH associated with connective tissue disease (CTD-PAH) in 3, PAH with congenital heart disease (CHD-PAH) in 2, and portal PAH in 1) or AT-877ER (6/5 females/males, 47±14 years, IPAH in 2, CTD-PAH in 5, and CHD-PAH in 4); 3 patients were excluded. We performed a 6-min walk test and right heart catheterization in the remaining 20 patients, before and 3 months after the treatment (placebo n=11, AT-877ER n=9). Although there were no significant differences between the 2 groups for the 6-min walk distance, pulmonary hemodynamics tended to be improved in the AT-877ER group, especially the prevalence of improved cardiac index from baseline, which was significantly higher in the AT-877ER than in the placebo group. In the AT-877ER group, serum levels of hydroxyfasudil, an active metabolite of AT-877ER tended to correlate with improvements in the cardiac index and mean pulmonary artery pressure. Conclusions Study DesignFrom the viewpoint of feasibility, the sample size was planned as 30 patients in total (10 patients for WHO functional class I and 20 for functional classes II-III. The present study was designed as a 3-month, double-blind, randomized, placebocontrolled, multicenter trial in which 14 PAH centers in Japan participated. All patients were hospitalized 3-6 days before the first examination (day 1) and the last examination (week 12) ( Figure S1). Administration of the study drug was started and ended during the hospitalization periods. Patients received either AT-877ER or placebo capsule twice daily (Asahi Kasei Pharma Corporation, Tokyo, Japan) for 12 weeks in a blind manner ( Figure S1). The dosage of AT-877ER was increased every 3 days in a stepwise manner from 2 to 6 capsules/day ( Figure S1). All patients were administered 2 capsules/day until day 4, when the dose was increased by the investigator's decision to 4 capsules/day. Until day 7, 4 capsules/day were given and the next doses were decided by investigators on day 7. Before increasing the study drug on days 4, 7, and 10, investigators checked the safety of the treatment in each subject and determined the subsequent treatment plan as follows.Whenever it was difficult to follow the intended regimen because of adverse effects or other reasons, the situation was required to be judged as "continuation at the dose level at the time of occurrence of the adverse drug reaction", "continuation with reduced dosage", or "discontinuation of study treatment". The treatment was randomized according to the 6-min walk distance, with drugs prescribed at baseline as stratifying factors, and...