The outcome of patients with osteosarcoma has not significantly improved in the last three decades. Therefore, there is still a need for the development of more effective therapeutic strategies. Methoxyamine (MX) is a...The outcome of patients with osteosarcoma has not significantly improved in the last three decades. Therefore, there is still a need for the development of more effective therapeutic strategies. Methoxyamine (MX) is a base excision repair (BER) inhibitor that has shown anticancer potential by sensitizing a variety of tumor cells to ionizing radiation and chemotherapeutic drugs. In the present study, the in vitro antiproliferative effects of MX were evaluated in two osteosarcoma cell lines, HOS and MG-63. Evaluation of the influence on radiosensitivity and drug interactions in simultaneous treatments with methotrexate, doxorubicin, and cisplatin was also performed. Exposure to MX significantly decreased cell proliferation and mediated a substantial increase of apoptosis. Moreover, our results showed that MX synergized with ionizing radiation in both cell lines while potentiated the antitumor effects of cisplatin and methotrexate. Altogether, the results presented herein demonstrate the feasibility of inhibiting the BER pathway, which may in future be a promising strategy for overcoming intrinsic tumor resistance and to improve the outcome of patients with osteosarcoma.展开更多
A convenient and highly efficient method is described for the synthesis of N-methoxycarbazole derivatives,including those with sterically demanding,benzannulated,or strongly electron-donating or-withdrawing substituen...A convenient and highly efficient method is described for the synthesis of N-methoxycarbazole derivatives,including those with sterically demanding,benzannulated,or strongly electron-donating or-withdrawing substituents.Various N-methoxycarbazole derivatives were directly prepared in good-to-moderate yields by the Pd_(2)(dba)_(3)CHCl_(3)/9,9-dimethyl-4,5-bis(diphenylphosphino)xanthene-catalyzed reactions of the corresponding dibromobiphenyl compounds and methoxyamine.Based on this methodology,the first total synthesis of 3,3′-[oxybis(methylene)]bis(9-methoxy-9H-carbazole),an antimicrobial dimeric carbazole alkaloid previously isolated from the stem bark of Murraya koenigii,was achieved in 18% yield over seven steps from 1,2-dibromobenzene.展开更多
文摘The outcome of patients with osteosarcoma has not significantly improved in the last three decades. Therefore, there is still a need for the development of more effective therapeutic strategies. Methoxyamine (MX) is a base excision repair (BER) inhibitor that has shown anticancer potential by sensitizing a variety of tumor cells to ionizing radiation and chemotherapeutic drugs. In the present study, the in vitro antiproliferative effects of MX were evaluated in two osteosarcoma cell lines, HOS and MG-63. Evaluation of the influence on radiosensitivity and drug interactions in simultaneous treatments with methotrexate, doxorubicin, and cisplatin was also performed. Exposure to MX significantly decreased cell proliferation and mediated a substantial increase of apoptosis. Moreover, our results showed that MX synergized with ionizing radiation in both cell lines while potentiated the antitumor effects of cisplatin and methotrexate. Altogether, the results presented herein demonstrate the feasibility of inhibiting the BER pathway, which may in future be a promising strategy for overcoming intrinsic tumor resistance and to improve the outcome of patients with osteosarcoma.
基金supported by the Natural Science Foundation of Tianjin,China(No.15JCYBJC20100).
文摘A convenient and highly efficient method is described for the synthesis of N-methoxycarbazole derivatives,including those with sterically demanding,benzannulated,or strongly electron-donating or-withdrawing substituents.Various N-methoxycarbazole derivatives were directly prepared in good-to-moderate yields by the Pd_(2)(dba)_(3)CHCl_(3)/9,9-dimethyl-4,5-bis(diphenylphosphino)xanthene-catalyzed reactions of the corresponding dibromobiphenyl compounds and methoxyamine.Based on this methodology,the first total synthesis of 3,3′-[oxybis(methylene)]bis(9-methoxy-9H-carbazole),an antimicrobial dimeric carbazole alkaloid previously isolated from the stem bark of Murraya koenigii,was achieved in 18% yield over seven steps from 1,2-dibromobenzene.
