The effects of bortezomib alone or in combination with 5-fluorouracil on proliferation and apoptosis of choriocarcinoma cells

Purpose: To investigate the effects of bortezomib alone and in combination with 5-fluorouracil (5-FU) on proliferation and apoptosis in the human choriocarcinoma cell line JEG-3. Materials and Methods: Cells were treated with bortezomib, 5-FU or with a combination. Proliferation and apoptosis were measured. NF-κB protein expression was examined using immunofluorescence. Results: Following treatment with ten nM bortezomib, rates of apoptosis were significantly higher than controls (p < 0.05) and NF-κB expression increased. 5-FU at 0.025 μg/ml or 0.25 μg/ml resulted in 60.1 ± 0.4% and 67.0 ± 0.2% growth inhibition, respectively, an increase compared to individual treatment (p < 0.05). Apoptosis in cells treated with bortezomib +5-FU was significantly higher than either treatment alone (p < 0.05). Inhibition of proliferation by the combination treatment was synergistic. Conclusion: Bortezomib alone or in combination with 5-FU inhibited JEG-3 cell proliferation and induced apoptosis by increasing NF-κB expression. Combination treatment exerted synergistic effects on growth inhibition.

Bortezomib; 5-fluorouracil; Apoptosis; Choriocarcinoma.

[1] Soundararajan R., Rao A.J.: “Trophoblast ‘pseudo-tumorigenesis’: Significance and contributory factors”. Reprod. Biol. Endocrinol., 2004, 2, 15.

[2] Berkowitz R.S., Goldstein D.P.: “Current management of gestational trophoblastic diseases”. Gynecol. Oncol., 2009, 112, 654.

[3] Nawrocki S.T., Carew J.S., Pino M.S., Highshaw RA, Dunner K Jr, Huang P., et al.: “Bortezomib sensitizes pancreatic cancer cells to endoplasmic reticulum stress-mediated apoptosis”. Cancer Res., 2005, 65, 11658.

[4] Driscoll J.J., Dechowdhury R.: “Therapeutically targeting the SUMOylation, Ubiquitination and Proteasome pathways as a novel anticancer strategy”. Target Oncol., 2010, 5, 281.

[5] Landowski T.H., Megli C.J., Nallmeyer K.D., Lynch R.M., Dorr R.T.: “Mitochondrialmediated disregulation of Ca2+ is a critical determinant of velcade (PS341/bortezomib)cytotoxicity in myeloma cell lines”. Cancer Res., 2005, 65, 3828.

[6] Adams J.: “The proteasome: a suitable antineoplastic target”. Nat. Rev. Cancer, 2004, 4, 349.

[7] Schmidt M., Hanna J., Elsasser S., Finley D.: “Proteasome-associated proteins: regulation of a proteolytic machine”. Biol. Chem., 2005, 386, 725.

[8] Laussmann M.A., Passante E., Düssmann H., Rauen J.A., Würstle M.L., Delgado M.E., et al.: “Proteasome inhibition can induce an autophagy-dependent apical activation of caspase-8”. Cell. Death. Differ., 2011, 18, 1584.

[9] D'Arcy P., Brnjic S., Olofsson M.H., Fryknäs M., Lindsten K., DeCesare M., et al.: “Inhibition of proteasome deubiquitinating activity as a new cancer therapy”. Nat. Med., 2011, 17, 1636.

[10] Dreicer R., Petrylak D., Agus D., Webb I., Roth B.: “Phase I/II study of bortezomib plus docetaxel in patients with advanced androgenindepentent prostate cancer”. Clin. Cancer Res., 2007, 13, 1208.

[11] Rushworth S.A., Bowles K.M., MacEwan D.J.: “High basal nuclear levels of Nrf2 in acute myeloid leukemia reduces sensitivity to proteasome inhibitors”. Cancer Res., 2011, 71, 1999.

[12] Kelly K.R., Espitia C.M., Mahalingam D., Oyajobi B.O., Coffey M., Giles F.J., et al.: “Reovirus therapy stimulates endoplasmic reticular stress, NOXA induction, and augments bortezomib-mediated apoptosis in multiple myeloma”. Oncogene, 2012, 31, 3023.

[13] Obeng E.A., Carlson L.M., Gutman D.M., Harrington W.J. Jr., Lee K.P., Boise L.H.: “Proteasome inhibitors induce a terminal unfolded protein response in multiple myeloma cells”. Blood, 2006, 107, 4907.

[14] Aghajanian C., Soignet S., Dizon D.S., Pien C.S., Adams J., Elliott P.J., et al.: “A phase I trial of the novel proteasome inhibitor PS 341 in advanced solid tumor malignancies ”. Clin. Cancer Res., 2002, 8, 2505.

[15] Chauhan D., Tian Z., Nicholson B., Kumar K.G., Zhou B., Carrasco R., et al.: “A small molecule inhibitor of ubiquitin-specific protease- 7 induces apoptosis in multiple myeloma cells and overcomes bortezomib resistance”. Cancer Cell., 2012, 22, 345.

[16] Al-Eisawi Z., Beale P., Chan C., Yu J.Q., Huq F.: “Modulation of cisplatin cytotoxicity due to its combination with bortezomib and the nature of its administration”. Anticancer Res., 2011, 31, 2757.

[17] Taylor-Harding B., Agadjanian H., Nassanian H., Kwon S., Guo X., Miller C., et al.: “Indole-3-carbinol synergistically sensitises ovarian cancer cells to bortezomib treatment”. Br. J. Cancer, 2012, 106,333.

[18] Ruschak A.M., Slassi M., Kay L.E., Schimmer A.D.: “Novel proteasome inhibitors to overcome bortezomib resistance”. J. Natl. Cancer Inst., 2011, 103, 1007.

[19] Li Y., Weng D.H., Kong F.F., Fan L.S., Hu Y., Song X.H., et al.: “Proteasome inhibitors sensitize ovarian cancer cells to cisplatin ”. Zhonghua Fu Chan Ke Za Zhi, 2010, 45, 445.

[20] Jandial D.D., Farshchi-Heydari S., Larson C.A., Elliott G.I., Wrasidlo W.J., Howell S.B.: “Enhanced delivery of cisplatin to intraperitoneal ovarian carcinomas mediated by the effects of bortezomib on the human copper transporter 1”. Clin. Cancer Res., 2009, 15, 553.

[21] Hougardy B.M., Maduro J.H., van der Zee A.G., de Groot D.J., van den Heuvel F.A., de Vries E.G., et al.: “Proteasome inhibitor MG132 sensitizes HPV-positive human cervical cancer cells to rhTRAIL-inducedapoptosis”. Int. J. Cancer, 2006, 118, 1892.

[22] Driscoll J.J., Minter A., Driscoll D.A., Burris J.K.: “The ubiquitin+ proteasome protein degradation pathway as a therapeutic strategyin the treatment of solid tumor malignancies”. Antican cer Agents Med. Chem., 2011. 11, 242.

[23] Ko B.S., Chang T.C., Chen C.H., Liu C.C., Kuo C.C., Hsu C., et al.: “Bortezomib suppresses focal adhesion kinase expression via interrupting nuclear factor-kappa B”. Life Sci., 2010, 86, 199.

[24] Lenz H.J.: “Clinical update:proteasome inhibitors in solid tumors”. Cancer Treat. Rev., 2003, 29, 41.

[25] Dolcet X., Llobet D., Encinas M., Pallares J., Cabero A., Schoenenberger J.A., et al.: “Proteasome inhibitors induce death but activate NF-kappaB on endometrial carcinoma cell lines and primary culture explants”. J. Biol. Chem., 2006, 281, 22118.