[Molecular mechanism and treatment strategy of colorectal cancer peritoneal metastasis].

Peritoneal metastatic colorectal cancer (pmCRC) is common and has been considered as the terminal stage. The theory of "seed and soil" and "oligometastasis" are the acknowledged hypotheses of pathogenesis of pmCRC. In recent years, the molecular mechanism related to pmCRC has been deeply researched. We realize that the formation of peritoneal metastasis, from detachment of cells from primary tumor to mesothelial adhesion and invasion, depends on the interplay of multiple molecules. Various components of tumor microenvironment also work as regulators in this process. Cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) have been widely used in clinical practice as an established treatment for pmCRC. Besides systemic chemotherapy, targeted and immunotherapeutic drugs are also increasingly used to improve prognosis. This article reviews the molecular mechanisms and treatment strategies related to pmCRC.

Iptakalim protects against hypoxic brain injury through multiple pathways associated with ATP-sensitive potassium channels.

The rapid and irreversible brain injury produced by anoxia when stroke occurs is well known. Cumulative evidence suggests that the activation of neuronal ATP-sensitive potassium (KATP) channels may have inherent protective effects during cerebral hypoxia, yet little information regarding the therapeutic effects of KATP channel openers is available. We hypothesized that pretreatment with a KATP channel opener might protect against brain injury induced by cerebral hypoxia. In this study, adult Wistar rats were treated with iptakalim, a new KATP channel opener, which is selective for SUR2 type KATP channels, by intragastric administration at doses of 2, 4, or 8 mg/kg/day for 7 days before being exposed to simulated high altitude equivalent to 8000 m in a decompression chamber for 8 h leading to hypoxic brain injury. By light and electron microscopic images, we observed that hypobaric hypoxia-induced brain injury could be prevented by pretreatment with iptakalim. It was also observed that the permeability of the blood-brain barrier, water content, Na+ and Ca2+ concentration, and activities of Na+,K+-ATPase, Ca2+-ATPase and Mg2+-ATPase in rat cerebral cortex were increased and the gene expression of the occludin or aquaporin-4 was down- or upregulated respectively, which could also be prevented by the pretreatment with iptakalim at doses of 2, 4, or 8 mg/kg in a dose-dependent manner. Furthermore, we found that in an oxygen-and-glucose-deprived model in ECV304 cells and rat cortical astrocytes, pretreatment with iptakalim significantly increased survived cell rates and decreased lactate dehydrogenate release, which were significantly antagonized by glibenclamide, a K(ATP) channel blocker. We conclude that iptakalim is a promising drug that may protect against brain injury induced by acute hypobaric hypoxia through multiple pathways associated with SUR2-type K(ATP) channels, suggesting a new therapeutic strategy for stroke treatment.