title: Highly activated p53 contributes to selectively increased apoptosis of latently HIV-1 infected cells upon treatment of anticancer drugs.
abstract: Despite the successful inhibition of human immunodeficiency virus type 1 (HIV-1) replication by combination antiretroviral therapy, cells latently infected with HIV-1 remaining in patients are a major obstacle for eradication of HIV-1 infection. The tumor suppressor factor p53 is activated by HIV-1 infection, and restricts HIV-1 replication. However, a therapeutic strategy based on p53 activity has not been considered for elimination of latently infected cells.
  
  
  
  Apoptotic cells were analyzed using flow cytometry with anti-annexin A5-FITC Ab and PI staining upon treatment of anticancer drugs. The expression and activation of p53 and apoptotic molecules in latently HIV-1-infected T cells were compared using Western blot analysis. The role of p53 in the anticancer drug treatment-induced apoptosis of cells latently infected with HIV-1 was determined by knock-down experiment using siRNA against p53.
  
  
  
  Upon treatment with 5-fluorouracil (5-FU), apoptosis was increased in latently infected ACH2 cells encoding competent p53 compared with uninfected parent A3.01 cells, while the apoptosis of latently infected p53 null J1.1 cells was less than that of uninfected cells. Treatment with 5-FU increased the levels of cleaved caspase-3 and PARP in ACH2 cells compared with uninfected and latently infected p53 null J1.1 cells. The levels of expression and activation of p53 were higher in both latently infected ACH2 and NCHA2 cells than in uninfected cells. Furthermore, the activation levels of p53 in both cells were further increased upon 5-FU treatment. Consistent with p53 status, apoptosis was markedly increased in ACH2 and NCHA2 cells compared with uninfected and latently infected J1.1 cells upon treatment with other anticancer drugs such as doxorubicin and etoposide. Inhibition of p53 in cells with latent HIV-1 infection diminished apoptosis upon 5-FU treatment.
  
  
  
  Evidence described here indicate that when treated with anticancer drugs, apoptosis of cells with latent HIV-1 infection was increased via the p53 activation pathway and may provide information for application of anticancer drugs to selectively eliminate HIV-1 reservoirs.
authors.affiliation: Division of AIDS, Center for Immunology and Pathology, Korea National Institute of Health, 187 Osongsaengmyeong 2-ro, Osong-yeup, Cheongju, Chungbuk, 363-951, South Korea.
authors.forename: YoungHyun
authors.initials: Y
authors.lastname: Shin
authors.affiliation: Division of AIDS, Center for Immunology and Pathology, Korea National Institute of Health, 187 Osongsaengmyeong 2-ro, Osong-yeup, Cheongju, Chungbuk, 363-951, South Korea.
authors.forename: Hoyong
authors.initials: H
authors.lastname: Lim
authors.affiliation: Division of AIDS, Center for Immunology and Pathology, Korea National Institute of Health, 187 Osongsaengmyeong 2-ro, Osong-yeup, Cheongju, Chungbuk, 363-951, South Korea.
authors.forename: Byeong-Sun
authors.initials: BS
authors.lastname: Choi
authors.affiliation: Division of AIDS, Center for Immunology and Pathology, Korea National Institute of Health, 187 Osongsaengmyeong 2-ro, Osong-yeup, Cheongju, Chungbuk, 363-951, South Korea.
authors.forename: Kyung-Chang
authors.initials: KC
authors.lastname: Kim
authors.affiliation: Division of AIDS, Center for Immunology and Pathology, Korea National Institute of Health, 187 Osongsaengmyeong 2-ro, Osong-yeup, Cheongju, Chungbuk, 363-951, South Korea.
authors.forename: Chun
authors.initials: C
authors.lastname: Kang
authors.affiliation: Department of Biological Sciences, Sungkyunkwan University, Suwon, Republic of Korea.
authors.forename: Yong-Soo
authors.initials: YS
authors.lastname: Bae
authors.affiliation: Division of AIDS, Center for Immunology and Pathology, Korea National Institute of Health, 187 Osongsaengmyeong 2-ro, Osong-yeup, Cheongju, Chungbuk, 363-951, South Korea. kmc755@korea.kr.
authors.forename: Cheol-Hee
authors.identifier: 0000-0002-5696-0567
authors.initials: CH
authors.lastname: Yoon
mesh_terms: D000970:Antineoplastic Agents / Q000378:metabolism*; D017209:Apoptosis; D005434:Flow Cytometry; D015497:HIV-1 / Q000502:physiology*; D006801:Humans; D013601:T-Lymphocytes / Q000187:drug effects* / Q000821:virology*; D016159:Tumor Suppressor Protein p53 / Q000378:metabolism*; D017735:Virus Latency / Q000187:drug effects*
chemical_list: D000970:Antineoplastic Agents; D016159:Tumor Suppressor Protein p53
keywords: Anticancer drugs; Apoptosis; Latently HIV-1 infected cells; Tumor suppressor p53