Antisense phosphorothioate oligodeoxynucleic acid for CD10 suppresses liver metastasis of colorectal cancer.

CD10 expression is associated with metastases of colorectal cancer (CRC). In the present study, we examined association of CD10 with liver metastasis of CRC cells to clarify the therapeutic significance of CD10. CD10-positive human colon cancer cell line, HT29 cells showed inhibition of growth, invasion and colony formation by treatment with CD10 antisense S-oligodeoxynucleotide (S-ODN). In the mouse liver metastasis mode, CD10 antisense S-ODN-treated HT29 cells made less embedded cells in the liver than control HT29 cells. Number and size of metastatic foci in nude mice liver were reduced in CD10 antisense S-ODN-treated HT29 cells. Treatment with CD10 antisense S-ODN decreased phosphorylation of ERK1/2 and EGFR in HT29 cells. Intraperitoneal administration of liposome-capsulated CD10 antisense S-ODN inhibited establishment of liver metastasis and growth of established metastasis in nude mice. These findings suggest that CD10 is associated substantially with liver metastasis of CRC cells and might be a molecular target of CRC treatment.

Suppression of dendritic cells by HMGB1 is associated with lymph node metastasis of human colon cancer.

High mobility groupbox-1 (HMGB1) is a multifunctional cytokine secreted by cancer cells, which accelerates cell growth, invasion and angiogenesis in cancer, and induces apoptosis in macrophages. Thioglycolate-stimulated mouse peritoneal macrophages were induced to differentiate into dendritic cells by co-treatment with IL-4 and GM-CSF. The number of mouse peritoneal macrophage-derived dendritic cells (PMDDCs) showed a dose-dependent decrease in hrHMGB1 treatment. HMGB1-treated PMDDCs showed obvious apoptosis and increased the level of phosphorylated JNK. Intraperitoneal administration of HMGB1 decreased CD205-positive splenic dendritic cells in C57BL mice. To confirm the HMGB1-induced inhibitory effect on dendritic cells, 16 cases of human colon cancer invaded into the subserosal layer were examined. The 8 nodal metastasis-positive cases showed higher nodal HMGB1 concentrations (74 +/- 23 vs. 41 +/- 15 microg/ml, p = 0.0116) in lymph node tissues and lower CD205-positive nodal dendritic cell numbers (86 +/- 22 vs. 137 +/- 43/mm(2), p = 0.0224) than those in the 8 metastasis-negative cases. Primary tumor tissues of metastasis-positive cases showed higher tumor HMGB1 levels (116 +/- 33 vs. 37 +/- 18 microg/ml, p = 0.0007) and lower CD205-positive intratumoral dendritic cell numbers (21 +/- 13 vs. 62 +/- 23 /mm(2), p = 0.0068) than those in metastasis-negative cases. These findings suggest that HMGB1 produced by colon cancer cells suppressed nodal dendritic cells to disturb host anti-cancer immunity.

Methionine-enkephalin secreted by human colorectal cancer cells suppresses T lymphocytes.

The role of methionine-enkephalin (MENK) as an immunomodulator in colorectal carcinomas (CRC) was examined. MENK was produced in CT26, IEC6A, Colo320, and HT29 CRC cell lines but not in IEC6 intestinal cells. MENK secretion was associated with tumorigenicity and metastasis of CRC cells in syngeneic rodent models. The MENK concentration in subcutaneous tumors of CT26 and IEC6A CRC cells exhibited an inverse correlation with the number of tumor-infiltrating T lymphocytes. MENK inhibited the growth of MOLT-4 T-lymphoblastic cells in a dose-dependent manner. Furthermore, it increased the phosphorylation level of c-Jun N-terminal kinase and induced apoptosis in MOLT-4 cells. MENK-induced apoptosis was abrogated by a c-Jun N-terminal kinase inhibitor. Immunohistochemical analysis revealed moderate to strong expression of MENK in 33 (54%) of 61 CRC. MENK expression was associated with Dukes' staging, nodal metastasis, and liver metastasis. The MENK concentration in tumor tissues was higher in Dukes' C cases than in Dukes' B cases. MENK expression was associated with tumor-infiltrating T lymphocytes, especially those belonging to the CD4(+) subset. These findings suggest that MENK secreted by CRC cells caused escape of the host from the effects of immunity.

Shear-induced discontinuous and continuous topological transitions in a hyperswollen membrane system.

Here we demonstrate that both discontinuous and continuous transition between the sponge and lamellar phase can be induced by steady shear flow for a hyperswollen membrane system. The discontinuous nature of the transition is revealed by a distinct hysteresis in the rheological behavior between shear-rate increasing and decreasing measurements at a constant temperature. This discontinuity becomes weaker with an increase in the shear rate and temperature, and the transition eventually becomes a continuous one without any hysteresis. We also found another shear-induced transition in a one-phase lamellar region. The dynamic phase diagram in a nonequilibrium steady state under shear is constructed for the sponge-lamellar transition as well as another transition in a stable lamellar phase. Possible physical mechanisms for these shear-induced transitions are discussed.

Spontaneous partitioning of particles into cellar structures in a membrane system.

Membranes are often used for material partitioning in biological systems and industry. Here we report a novel physical mechanism of particle partitioning using topological transformation of bilayer membranes. Upon phase separation of a homogeneous sponge phase of a membrane system into a dense sponge and a water phase, we found quite unusual partitioning behavior of particles into the cellar structure of a water phase. The compartments next to one having particles always have no particles, and those next to a compartment having no particles always have particles. We confirm that this partitioning is purely geometrically induced, and thus it may be universal.