Blockade of irradiation-induced autophagosome formation impairs proliferation but does not enhance cell death in HCT-116 human colorectal carcinoma cells

  • Authors:
    • Ana Cristina de Albuquerque-Xavier
    • Lilian Gonçalves R. Bastos
    • Julio Cesar Madureira de Freitas
    • Fernanda Leve
    • Waldemir Fernández de Souza
    • Wallace  Martins de Araujo
    • João Luiz Mendes Wanderley
    • Marcelo  Neves Tanaka
    • Wanderley de Souza
    • José Andrés Morgado-Díaz
  • View Affiliations

  • Published online on: January 10, 2012     https://doi.org/10.3892/ijo.2012.1329
  • Pages: 1267-1276
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Abstract

This work was undertaken to gain further information on the molecular mechanisms underlying autophagosome formation and its relation with tumor cell survival in response to radiation in colon cancer. A human colon cancer cell line, HCT-116, was examined with respect to cell survival after blockade of irradiation-induced autophagosome formation by pharmacological interference. Autophagosome formation was confirmed using a kinetic study with incorporated bovine serum albumin gold-conjugate (BSA-Au) analyzed by electron microscopy and an autophagosome-associated LC3B antibody measured by immunofluorescence and Western blotting. Annexin V/PI double staining was used to monitor cell death by apoptosis, and cell cycle profiles by flow cytometry. Ionizing radiation (IR) promoted autophagosome formation in the HCT-116 IR-surviving cells. Pharmacological interference showed that PI3K/Akt and Src were involved in early stages of autophagosome formation. IR alone decreased cell proliferation by arresting cells in the G2/M phase, and pharmacological interference of autophagosome formation decreased proliferation, but did not affect cell survival. Also, our data suggest that decreased proliferation caused by PI3K and Src inhibitors could be through S phase cell cycle delay. Our results clearly indicate that blockade of IR-induced autophagosome formation impairs proliferation but does not enhance cell death in colon cancer cells.
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April 2012
Volume 40 Issue 4

Print ISSN: 1019-6439
Online ISSN:1791-2423

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Spandidos Publications style
de Albuquerque-Xavier AC, Bastos LG, de Freitas JC, Leve F, de Souza WF, de Araujo WM, Wanderley JL, Tanaka MN, de Souza W, Morgado-Díaz JA, Morgado-Díaz JA, et al: Blockade of irradiation-induced autophagosome formation impairs proliferation but does not enhance cell death in HCT-116 human colorectal carcinoma cells. Int J Oncol 40: 1267-1276, 2012
APA
de Albuquerque-Xavier, A.C., Bastos, L.G., de Freitas, J.C., Leve, F., de Souza, W.F., de Araujo, W.M. ... Morgado-Díaz, J.A. (2012). Blockade of irradiation-induced autophagosome formation impairs proliferation but does not enhance cell death in HCT-116 human colorectal carcinoma cells. International Journal of Oncology, 40, 1267-1276. https://doi.org/10.3892/ijo.2012.1329
MLA
de Albuquerque-Xavier, A. C., Bastos, L. G., de Freitas, J. C., Leve, F., de Souza, W. F., de Araujo, W. M., Wanderley, J. L., Tanaka, M. N., de Souza, W., Morgado-Díaz, J. A."Blockade of irradiation-induced autophagosome formation impairs proliferation but does not enhance cell death in HCT-116 human colorectal carcinoma cells". International Journal of Oncology 40.4 (2012): 1267-1276.
Chicago
de Albuquerque-Xavier, A. C., Bastos, L. G., de Freitas, J. C., Leve, F., de Souza, W. F., de Araujo, W. M., Wanderley, J. L., Tanaka, M. N., de Souza, W., Morgado-Díaz, J. A."Blockade of irradiation-induced autophagosome formation impairs proliferation but does not enhance cell death in HCT-116 human colorectal carcinoma cells". International Journal of Oncology 40, no. 4 (2012): 1267-1276. https://doi.org/10.3892/ijo.2012.1329