A phase-II clinical trial of laparoscopy-assisted distal gastrectomy with D2 lymph node dissection for gastric cancer patients.

Objectives: This study was conducted to determine whether laparoscopy-assisted distal gastrectomy (LADG) with complete D2 lymph node dissection for gastric cancer is a safe and effective surgical option.

Methods: During an 8-month period, 64 patients, who were diagnosed preoperatively as having T1-2, N0-1 or M0 gastric cancer, were prospectively enrolled to undergo LADG with D2 lymph node dissection; two surgeons with experience of over 50 cases of laparoscopic gastrectomy performed the procedures. The compliance rate, defined as cases with no more than one missing lymph node station according to the Japanese Research Society of Gastric Cancer (JRSGC) lymph node grouping, for the open gastrectomy with D2 lymph node dissection was 66.

Grb2 negatively regulates epidermal growth factor-induced phospholipase C-gamma1 activity through the direct interaction with tyrosine-phosphorylated phospholipase C-gamma1.

Phospholipase C-gamma1 (PLC-gamma1) plays pivotal roles in cellular growth and proliferation. Upon the stimulation of growth factors and hormones, PLC-gamma1 is rapidly phosphorylated at three known sites; Tyr771, Tyr783 and Tyr1254 and its enzymatic activity is up-regulated. In this study, we demonstrate for the first time that Grb2, an adaptor protein, specifically interacts with tyrosine-phosphorylated PLC-gamma1 at Tyr783.

Polyacetylenes from a marine sponge Petrosia sp. inhibit DNA replication at the level of initiation.

In the course of our search for bioactive metabolites from the marine sponges collected from Korean water, we found that the polyacetylenes of marine sponge, genus Petrosia, deliver significant selective cytotoxicity against several human tumor cell lines. The effects of polyacetylene on DNA replication were examined using simian virus 40 DNA replication system in vitro. We found that polyacetylenes inhibited DNA replication, and predominantly inhibited the initiation stage of DNA replication.

Effects of adenine-nucleotides on the sequence-specificity of origin recognition complex-binding to DNA.

We examined effects of adenine-nucleotides on the sequence-specificity of origin recognition complex (ORC)-binding to DNA, using a gel electrophoretic mobility shift assay. The sequence-specific DNA binding of ORC was observed in the presence of ATP or ATP-gamma-S but not in the presence of adenosine 5'-diphosphate (ADP) or in the absence of any adenine-nucleotides. In contrast, the sequence-independent DNA binding of ORC was observed under any one of these conditions.

Acidic phospholipids with unsaturated fatty acids inhibit the binding of origin recognition complex to origin DNA.

Origin Recognition Complex (ORC) is a candidate initiator of chromosomal DNA replication in eukaryotes. We recently reported that cardiolipin inhibits the interaction of Origin Recognition Complex ORC with origin DNA, as is the case of DnaA, the initiator of chromosomal DNA replication in prokaryotes. We report here that another acidic phospholipid, phosphatidylglycerol (PG), also inhibits the interaction.

Inhibitory effects of acidic phospholipids on the binding of origin-recognition complex to origin DNA.

Origin-recognition complex (ORC), a candidate initiator of chromosomal DNA replication in eukaryotes, shares certain biochemical characteristics with DnaA, the initiator of chromosomal DNA replication in prokaryotes. These similarities include origin-specific DNA binding, ATP binding and ATPase activity. DnaA interacts with acidic phospholipids, such as cardiolipin, and its activity is regulated by these phospholipids.