Antiangiogenic effects of a novel synthetic curcumin analogue in pancreatic cancer.

Hypoxia-inducible factors (HIFs) and NF-κB play essential roles in cancer cell growth and metastasis by promoting angiogenesis. Heat shock protein 90 (Hsp90) serves as a regulator of HIF-1α and NF-κB protein. We hypothesized that curcumin and its analogues EF31 and UBS109 would disrupt angiogenesis in pancreatic cancer (PC) through modulation of HIF-1α and NF-κB. Conditioned medium from MIA PaCa-2 or PANC-1 cells exposed to curcumin and its analogues in vitro significantly impaired angiogenesis in an egg CAM assay and blocked HUVEC tube assembly in comparison to untreated cell medium. In vivo, EF31 and UBS109 blocked the vascularization of subcutaneous matrigel plugs developed by MIA PaCa-2 in mice. Significant inhibition of VEGF, angiopoietin 1, angiopoietin 2, platelet derived growth factor, COX-2, and TGFβ secretion was observed in PC cell lines treated with UBS109, EF31 or curcumin. Treatment with UBS109, EF31 or curcumin inhibited HSP90, NF-κB, and HIF-1α transcription in PC cell lines. UBS109 and EF31 inhibited HSP90 and HIF-1α expression even when elevated due to NF-κB (p65) overexpression. Finally, we demonstrate for the first time that curcumin analogues EF31 and UBS109 induce the downregulation of HIF-1α, Hsp90, COX-2 and VEGF in tumor samples from xenograft models compared to untreated xenografts. Altogether, these results suggest that UBS109 and EF31 are potent curcumin analogues with antiangiogenic activities.

Nagaraju GP ，Zhu S ，Ko JE ，Ashritha N ，Kandimalla R ，Snyder JP ，Shoji M ，El-Rayes BF ... -  《-》

Novel synthetic curcumin analogs as potent antiangiogenic agents in colorectal cancer.

The transcription factor NF-κB plays a central role in angiogenesis in colorectal cancer (CRC). Curcumin is a natural dietary product that inhibits NF-κB. The objective of this study is to evaluate the antiangiogenic effects of curcumin and two potent synthetic analogues (EF31 and UBS109) in CRC. IC50 values for curcumin, EF31, and UBS109 were determined in the HCT116 and HT-29 cell lines. HUVEC tube formation, egg CAM assay, and matrigel plug assays revealed decreased angiogenesis in cell lines treated with curcumin, EF31, or UBS109. Curcumin and its analogues significantly inhibited VEGF-A synthesis and secretion in both cell lines in association with loss of HIF-1α, COX-2, and p-STAT-3 expression. Nuclear NF-κB expression was inhibited by curcumin, EF31, and UBS109. Transfection of p65-NF-κB in HCT116 and HT-29 cells resulted in increased expression of HIF-1α, COX-2, STAT-3, and VEGF-A. Treatment with curcumin, EF31, or UBS109 inhibited these effects in transfected cell lines. In mice carrying HCT116 and HT-29 cell xenografts, EF31 and UBS109 inhibited subcutaneous tumor growth and potentiated the effects of oxaliplatin and 5-FU. Tumors from treated animals revealed inhibition of HIF-1α, COX-2, p-STAT-3, and VEGF expression. Our findings suggest that inhibition of NF-κB leading to decreased transcription and expression of HIF-1α, COX-2, STAT-3, and VEGF is a rational approach for antiangiogenic therapy in CRC. The distinctive properties of EF31 and UBS109 make them promising therapeutic agents for development in CRC as single agents or as part of combination chemotherapy regimens. © 2016 Wiley Periodicals, Inc.

Rajitha B ，Nagaraju GP ，Shaib WL ，Alese OB ，Snyder JP ，Shoji M ，Pattnaik S ，Alam A ，El-Rayes BF ... -  《-》

Novel synthetic curcumin analogues EF31 and UBS109 are potent DNA hypomethylating agents in pancreatic cancer.

DNA methylation is a rational therapeutic target in pancreatic cancer. The activity of novel curcumin analogues EF31 and UBS109 as demethylating agents were investigated. MiaPaCa-2 and PANC-1 cells were treated with vehicle, curcumin, EF31 or UBS109. EF31 and UBS109 resulted in significantly higher inhibition of proliferation and cytosine methylation than curcumin. Demethylation was associated with re-expression of silenced p16, SPARC, and E-cadherin. EF31 and UBS109 inhibited HSP-90 and NF-κB leading to downregulation of DNA methyltransferase-1 (DNMT-1) expression. Transfection experiments confirmed this mechanism of action. Similar results were observed in vitro when subcutaneous tumors (MiaPaCa-2) were treated with EF31 and UBS109.

Nagaraju GP ，Zhu S ，Wen J ，Farris AB ，Adsay VN ，Diaz R ，Snyder JP ，Mamoru S ，El-Rayes BF ... -  《-》

Antiangiogenic effects of ganetespib in colorectal cancer mediated through inhibition of HIF-1α and STAT-3.

Nagaraju GP ，Park W ，Wen J ，Mahaseth H ，Landry J ，Farris AB ，Willingham F ，Sullivan PS ，Proia DA ，El-Hariry I ，Taliaferro-Smith L ，Diaz R ，El-Rayes BF ... -  《-》

Inhibition of NF-κB translocation by curcumin analogs induces G0/G1 arrest and downregulates thymidylate synthase in colorectal cancer.

Cell cycle progression and DNA synthesis are essential steps in cancer cell growth and resistance. Thymidylate synthase (TS) is a therapeutic target for 5FU. Curcumin is a potent inhibitor of NF-κB. EF31 and UBS109 are potent synthetic analogues of curcumin. We tested the hypothesis that inhibition of NF-κB translocation by curcumin and its analogs EF31 and UBS109 can inhibit cell cycle progression and downregulate TS levels in colorectal cancer (CRC) cell lines. Two CRC cell lines (HCT116 and HT-29) were either untreated (control) or treated with IC50 concentrations of curcumin, EF31 UBS109 led to G0/G1 cell cycle arrest. Treatment with curcumin, EF31 or UBS109 inhibited NF-κB, downregulated survival pathways and inhibited cell cycle progression. Arrest in the G0/G1 phase was associated with downregulation of the transcription factor E2F-1 and its target gene TS. NF-κB over-expression induced E2F-1 and TS protein and mRNA levels in both cell lines. EF31 and UBS109 treatment significantly decreased tumor growth in compared to untreated tumors. EF31 and UBS109 are promising agents for the prevention and treatment of CRC.

Rajitha B ，Belalcazar A ，Nagaraju GP ，Shaib WL ，Snyder JP ，Shoji M ，Pattnaik S ，Alam A ，El-Rayes BF ... -  《-》