Atelocollagen-mediated systemic delivery prevents immunostimulatory adverse effects of siRNA in mammals.

Short interfering RNA (siRNA) is a potent activator of the mammalian innate immune system. When considering possible clinical applications of siRNA for humans, the adverse immunostimulatory effects must also be taken into account. Here, we show that atelocollagen-mediated systemic delivery of siRNA without chemical modifications did not cause any immunostimulation in both animals and human peripheral blood mononuclear cells (PBMCs), even if the siRNA harbored an interferon (IFN)-inducible sequence.

The metastasis-associated microRNA miR-516a-3p is a novel therapeutic target for inhibiting peritoneal dissemination of human scirrhous gastric cancer.

Although aberrant microRNA (miRNA) is expressed in different types of human cancer tissues, its pathophysiologic role and the relevance of tumorigenesis and metastasis are still largely unknown. Here, we defined miRNAs involved in cancer metastasis (metastamirs) using an established mouse model for peritoneal dissemination of human scirrhous gastric carcinoma cells. Highly metastatic derivatives (44As3 cells) were derived from the parental cells originally isolated from patients (HSC-44PE cells).

Systemic delivery of siRNA specific to tumor mediated by atelocollagen: combined therapy using siRNA targeting Bcl-xL and cisplatin against prostate cancer.

The largest obstacle to the effective use of short interfering RNA (siRNA) in an animal body is the ability to deliver it to the target tissue. Here we showed a systemic delivery method of siRNA specific to pregrown solid tumors via atelocollagen. Atelocollagen facilitated the selective uptake of siRNA into the tumors when an siRNA/atelocollagen complex was administered intravenously to mice.

Downregulation of monocyte chemoattractant protein-1 involving short interfering RNA attenuates hapten-induced contact hypersensitivity.

Contact hypersensitivity (CHS) is a common skin disease, presenting clinically as allergic contact dermatitis. At inflammatory sites in a typical CHS model in the mouse ear, elevated expression of monocyte chemoattractant protein-1 (MCP-1) has been reported. MCP-1 is a potent chemotactic factor for many types of leukocytes including monocytes/macrophages and T cells.