lignans and Lymphoma

Honokiol and triphenylmethanes are small molecules with anti-tumor properties. Recently, we synthesized new honokiol analogues (HAs) that possess common features of both groups. We assessed the anti-tumor effectiveness of HAs in B-cell leukemia/lymphoma cells, namely in chronic lymphocytic leukemia (CLL) cells ex vivo and in pre-B-cell acute lymphoblastic leukemia (Nalm-6), Burkitt lymphoma (BL; Raji), diffuse large B-cell lymphoma (DLBCL; Toledo) and multiple myeloma (MM; RPMI 8226) cell lines. Four of these compounds appeared to be significantly active against the majority of cells examined, with no significant impact on healthy lymphocytes. These active HAs induced caspase-dependent apoptosis, causing significant deregulation of several apoptosis-regulating proteins. Overall, these compounds downregulated Bcl-2 and XIAP and upregulated Bax, Bak and survivin proteins. In conclusion, some of the HAs are potent tumor-selective inducers of apoptosis in ex vivo CLL and in BL, DLBCL and MM cells in vitro. Further preclinical studies of these agents are recommended.

Topics: Antineoplastic Agents; Apoptosis; Apoptosis Regulatory Proteins; Biphenyl Compounds; Cell Line, Tumor; Cell Proliferation; Cell Survival; Drug Screening Assays, Antitumor; Gene Expression Regulation, Neoplastic; Humans; Leukemia; Lignans; Lymphoma; Multiple Myeloma; Trityl Compounds

Purpose of work: The study was aimed to assess the antineoplastic activity of justicidin B in vitro and to search for its general toxicological profile in vivo. The anti-neoplastic activity of the arylnaphthalene lignin, justicidin B, was assessed in a panel of human lymphoma cell lines and compared with etoposide as a reference compound. A screening of the cytotoxicity after 24, 48 and 72 h exposure was performed by the MTT-dye reduction assay. Dose- and time-dependent cytotoxic effect was observed and the IC50 values ranged from 0.17 µM (RPMI-8226, 72 h) to 183 µM (U-266, 24 h) and more than 200 µM (HD-MY-Z, 24 and 48 h). Activation of caspase 3 and 8 was involved in the induction of programmed cell death in DOHH-2 cell line. NF-κB modulation occurred in DOHH-2 and HH cells. The general toxicity in mice after i.p. injection was also tested. The highest applied dose (50 mg/kg = 137.25 µM) did not show any toxicity. Justicidin B possesses definite and potent selective antineoplastic activity, related to its ability to induce programmed cell death in NHL-derived human cell lines at concentrations that can be reached in mice without toxicity.

Topics: Animals; Antineoplastic Agents; Apoptosis; Caspases; Cell Line, Tumor; Dioxolanes; Etoposide; Female; Humans; Lignans; Lymphoma; Male; Mice; NF-kappa B

The hydroalcoholic extract of the steam bark of B. fagaroides var. fagaroides displayed potent cytotoxic activity against four cancer cell lines, namely KB (ED50 = 9.6 × 10(-2) μg/mL), PC-3 (ED50 = 2.5 × 10(-1) μg/mL), MCF-7 (ED50 = 6.6 μg/mL), and HF-6 (ED50 = 7.1 × 10(-3) μg/mL). This extract also showed anti-tumour activity when assayed on mice inoculated with L5178Y lymphoma cells. Bioactivity-directed isolation of this extract, afforded seven podophyllotoxin-type lignans identified as podophyllotoxin (1), β-peltatin-A-methylether (2), 5'-desmethoxy-β-peltatin-A-methylether (3), desmethoxy-yatein (4), desoxypodophyllotoxin (5), burseranin (6), and acetyl podophyllotoxin (7) by 1D and 2DNMR and FAB-MS analyses, and comparison with reported values. All the isolated compounds showed potent cytotoxic activity in the cell lines tested, especially compound 3, which exhibited greater activity than camptothecin and podophyllotoxin against PC-3 (ED50= 1.0 × 10(-5) μg/mL), and KB (ED50 = 1.0 × 10(-5) μg/mL). This is the first report of the isolation of podophyllotoxin and its acetate in a Bursera species.

Topics: Animals; Antineoplastic Agents, Phytogenic; Bursera; Cell Line, Tumor; Humans; Lignans; Lymphoma; Male; Mice; Mice, Inbred BALB C; Plant Extracts; Podophyllotoxin; Xenograft Model Antitumor Assays