Reference

Cell membrane signaling as target in cancer therapy II: inhibitory effect of N,N,N-trimethylsphingosine on metastatic potential of murine B16 melanoma cell line through blocking of tumor cell-dependent platelet aggregation

Cell membrane signaling as target in cancer therapy II: inhibitory effect of N,N,N-trimethylsphingosine on metastatic potential of murine B16 melanoma cell line through blocking of tumor cell-dependent platelet aggregation. [Erratum to document cited in CA116(7):51030f].In this study， 119567-63-4 and 56-65-5 are also used. Okoshi, Hirofumi; Hakomori, Senitiroh; Nisar, Mohammad; Zhou, Qinghong; Kimura, Satoshi; Tashiro, Kazuhiro; Igarashi, Yasuyuki (Biomembr. Inst., Seattle, WA 98119, USA). Cancer Res., 52(2), 498 (English) 1992. CODEN: CNREA8. ISSN: 0008-5472. DOCUMENT TYPE: Journal CA Section: 1 (Pharmacology) An error in the text has been cor. The error was not reflected in the abstr. or the index entries. .

In vitro and in vivo induction of apoptosis by sphingosine and N,N-dimethylsphingosine in human epidermoid carcinoma KB-3-1 and its multidrug-resistant cells

In vitro and in vivo induction of apoptosis by sphingosine and N,N-dimethylsphingosine in human epidermoid carcinoma KB-3-1 and its multidrug-resistant cells. Shirahama, Tsutomu; Sweeney, Elizabeth A.; Sakakura, Chouhei; Singhal, Anil K.; Nishiyama, Kenryu; Akiyama, Shin-Ichi; Hakomori, Sen-Itiroh; Igarashi, Yasuyuki (The Biomembrane Institute, Seattle, WA 98119-4237, USA). Clinical Cancer Research, 3(2), 257-264 (English) 1997 American Association for Cancer Research. CODEN: CCREF4. ISSN: 1078-0432. DOCUMENT TYPE: Journal CA Section: 1 (Pharmacology) Sphingolipid breakdown products, including ceramide and sphingosine, regulate cell growth, cell differentiation, and apoptosis. We examd. the effect of various agents, including sphingolipids, on apoptosis induction in human epidermoid carcinoma KB-3-1 and its multidrug-resistant (MDR) subclone KB-C2 cells which express P-glycoprotein. Adriamycin (ADM) induced apoptosis in KB-3-1 cells but not in KB-C2 MDR cells at the concn. of 50 mg/mL. On the other hand, 15 mM sphingosine or its methylated deriv. N,N-demethylsphingosine (DMS) induced apoptosis in both cell types in vitro.Several substances with their cas registry numbers 119567-63-4 and 141436-78-4 may be metioned in this study. These results suggested that KB-C2 MDR cells were resistant to apoptosis induction by ADM but sensitive to that by sphingosine and DMS. Ceramide and sphingosine-1-phosphate, the initial metabolites of sphingosine, failed to induce apoptosis under the same exptl. condition as sphingosine/DMS. The protein kinase C (PKC) inhibitors H7 and staurosporine did not induce apoptosis in either cell line, suggesting that PKC-independent signaling is involved in apoptosis induced by sphingosine and DMS, although both sphingosine and DMS have been shown to down-regulate PKC. Furthermore, DMS significantly inhibited the growth of KB-3-1 as well as KB-C2 MDR tumors in vivo, with evidence of increased apoptosis. The intracellular level of exogenously added [3H]sphingosine or [14C]ADM did not differ between the KB-3-1 parent cell line and its MDR subclone KB-C2, whereas that of [14C]ADM was reduced in KB-C2 MDR cells compared to KB-3-1 cells. These results suggest that P-glycoprotein acts as a transporter for ADM but not for sphingosine or DMS. Furthermore, DMS at the concns. which induce apoptosis in KB-C2 cells did not affect the level of [14C]ADM. Because sphingosine and DMS induce apoptosis regardless of P-glycoprotein expression, they may provide a new strategy and a promising approach to the treatment of anticancer drug-resistant cancer. .