Potential targets and therapeutics for cancer stem cell-based therapy against drug resistance in hepatocellular carcinoma.

Hepatocellular carcinoma (HCC) is the most common digestive malignancyin the world, which is frequently diagnosed at late stage with a poor prognosis. For most patients with advanced HCC, the therapeutic options arelimiteddue to cancer occurrence of drug resistance. Hepatic cancer stem cells (CSCs) account for a small subset of tumor cells with the ability of self-renewal and differentiationin HCC. It is widely recognized that the presence of CSCs contributes to primary and acquired drug resistance. Therefore, hepatic CSCs-targeted therapy is considered as a promising strategy to overcome drug resistance and improve therapeutic outcome in HCC. In this article, we review drug resistance in HCC and provide a summary of potential targets for CSCs-based therapy. In addition, the development of CSCs-targeted therapeuticsagainst drug resistance in HCC is summarized in both preclinical and clinical trials. The in-depth understanding of CSCs-related drug resistance in HCC will favor optimization of the current therapeutic strategies and gain encouraging therapeutic outcomes.

Mechanisms and targeted reversion/prevention of hepatic fibrosis caused by the non-hereditary toxicity of benzo(a)pyrene.

The effect of long term exposure to low concentrations of environmental pollutants on hepatic disorders is a major public health concern worldwide. Polycyclic aromatic hydrocarbons (PAHs) are a class of persistent organic pollutants. In recent years, an increasing number of studies have focused on the deleterious effects of low concentrations of PAHs in the initiation or exacerbation of the progression of chronic liver disease. However, the underlying molecular mechanisms and effective intervention methods remain unclear. Here, we found that in hepatocytes, a low concentration of benzo(a)pyrene (B[a]P, an indicator of PAHs) chronic exposure continuously activated 14-3-3η via an epigenetic accumulation of DNA demethylation. As a "switch like" factor, 14-3-3η activated its downstream PI3K/Akt signal, which in turn promoted vascular endothelial growth factor (VEGF) production and secretion. As the characteristic fibrogenic paracrine factor regulated by B[a]P/14-3-3η, VEGF significantly induced the neovascularization and activation of hepatic stellate cells, leading to the development of hepatic fibrosis. Importantly, targeted 14-3-3η by using its specific inhibitor invented by our lab could prevent B[a]P-induced hepatic fibrosis, and could even reverse existent hepatic fibrosis caused by B[a]P. The present study not only revealed novel mechanisms, but also proposed an innovative approach for the targeted reversion/prevention of the harmful effects of exposure to PAHs on chronic liver disease.

Triflylpyridinium Enables Rapid and Scalable Controlled Reduction of Carboxylic Acids to Aldehydes using Pinacolborane.

Building up new and efficient methods for the controlled conversion of carboxylic acids to aldehydes is important. Herein, we report a rapid, modular and scalable method for the conversion of carboxylic acids to aldehydes using pinacolborane at ambient temperature, in which a triflylpyridinium reagent is used. The conversion of carboxylic acid to intermediate acylpyridinium by triflylpyridinium is new. A binary pyridine-coordinated boronium complex is generated after reduction. The unprecedented reduction of the acylpyridinium by HBpin opens up a practically direct synthesis of aldehydes from carboxylic acids. Theoretical studies indicate that the reduction of acylpyridinium requires a lower activation free energy than that of the product aldehyde. The synthetic advantage of this protocol is further highlighted by the scalable synthesis of aldehyde via continuous flow process. Configuration retention for chiral acids are presented in those syntheses.

Tandem Synthesis of 2-Carboxybenzofurans via Sequential Cu-Catalyzed C-O Coupling and Mo(CO)6-Mediated Carbonylation Reactions.

A modular tandem synthesis of 2-carboxybenzofurans from 2-gem-dibromovinylphenols has been established based on a sequence of Cu-catalyzed intramolecular C-O coupling and Mo(CO)6-mediated intermolecular carbonylation reactions. This protocol allowed one-step access to a broad variety of functionalized benzofuran-2-carboxylic acids, esters, and amides in good to excellent yields under Pd- and CO gas-free conditions.

[Modification and efficacy observation of laparoscopic dual anastomosis for mid-low rectal cancer].

OBJECTIVE: To explore a new procedure of laparoscopic dual anastomosis for mid-low rectal cancer to reduce postoperative complications. METHODS: Clinical data of 56 patients with mid-low rectal cancer undergoing laparoscopic rectal cancer resection(modified double-stapling technique, MDST, modification group) in the Department of General Surgery, the First Affiliated Hospital of Soochow University from February 2010 to June 2014 were compared with the data of 64 patients with mid-low rectal cancer (conventional double-stapling technique, DST, convention group) in the same period based on gender, age, tumor size, the distance from lower edge to the dentate line and tumor staging, etc. Patients in the modification group received operation as follows: (1) the rectum distal end was closed vertically instead of horizontally. (2) the anastomosis was conducted in an "end-corner" approach. (3) upper corner of the closed line in the distal end of rectum was removed. (4) the lower corner of closed line in the distal end of rectum was removed using vascular occlusion clamp method. (5) two T-shaped interchanges ("dangerous triangle") of stapled sutures formed after anastomosis were strengthened with absorbable suture. Patients in the convention group received laparoscopic dual anastomosis using conventional method: two corners and "dangerous triangles" were kept without any treatment. The clinical outcomes of two groups were analyzed retrospectively. RESULTS: The intraoperational blood loss, postoperative drainage volume, postoperative anastomotic stoma bleeding, bowel function return and hospital stay were not significantly different between the two groups (all P>0.05). As compared to the convention group, the modification group had longer operation time [(211 ± 91) min vs. (174 ± 57) min, P<0.05], lower incidence of postoperative anastomotic leakage [1.8%(1/56) vs. 12.5% (8/64), P=0.030], lower tenesmus rate [3.6% (2/56) vs. 14.1% (9/64), P<0.05], less postoperative stoma re-creation [0 vs. 9.4% (6/64), P<0.05]. CONCLUSION: Modified laparoscopic dual anastomosis for mid-low rectal cancer can significantly reduce the incidence of post-surgical complications such as anastomotic leakage.