Takahashi Masato, Seki Naohiko, Ozaki Toshinori, Kato Masaki, Kuno Tomoko, Nakagawa Takahito, Watanabe Ken-ichi, Miyazaki Koh, Ohira Miki, Hayashi Shunji, Hosoda Mitsuchika, Tokita Hisashi, Mizuguchi Hiroyuki, Hayakawa Takao, Todo Satoru, Nakagawara Akira
Division of Biochemistry, Chiba Cancer Center Research Institute, Chuoh-ku, Chiba 260-8717, Japan.
Cancer Res. 2002 Apr 15;62(8):2203-9.
The candidate tumor suppressor p33(ING1) plays an important role in inducinggrowth arrest at G(0)-G(1) phase of the cell cycle and/or promoting apoptosis in cancerous cells. p33(ING1) is reported to act as a transcriptional cofactor by associating with tumor suppressor p53, HAT, or histone deacetyltransferase, suggesting that p33(ING1) is involved in chromatin-mediated transcriptional regulation. However, the molecular mechanism of p33(ING1)-mediated transcriptional regulation is poorly understood. Here we analyzed expression profiles in mouse mammary epithelial cells (NMuMG) by using a cDNA microarray consisting of 2304 mouse cDNAs after inducing transformation with antisense inhibitor of growth 1 (ING1) in retrovirus vector. The subsequent confirmation of the altered expression levels of the selected genes by semiquantitative reverse transcription-PCR demonstrated that overexpression of the antisense ING1 stimulated expression of 14 genes, which included cyclin B1, 12-O-tetradecanoylphorbol-13-acetate-inducible sequence 11, proto-oncogene DEK, and osteopontin, whereas we have detected transcriptional repression of 5 genes, including TPT1. In addition, adenovirus-mediated overexpression of ING1 in NMuMG cells resulted in down-regulation of cyclin B1, 12-O-tetradecanoylphorbol-13-acetate-inducible sequence 11, DEK, and osteopontin, whereas the levels of TPT1 expression were increased. The further analysis using p53(-/-) SAOS2 cells showed that the p33(ING1)-induced cyclin B1 down-regulation was p53 dependent. Thus, our cDNA microarray analysis suggested that p33(ING1) targets the multiple genes, including proto-oncogene DEK and cyclin B1, at least some of which are regulated in a p53-dependent manner, in the cells undergoing cell growth or apoptosis.
候选肿瘤抑制因子p33(ING1)在诱导细胞周期的G(0)-G(1)期生长停滞和/或促进癌细胞凋亡中起重要作用。据报道，p33(ING1)通过与肿瘤抑制因子p53、组蛋白乙酰转移酶（HAT）或组蛋白去乙酰化酶结合而作为转录辅因子，这表明p33(ING1)参与染色质介导的转录调控。然而，p33(ING1)介导的转录调控的分子机制尚不清楚。在这里，我们使用由2304个小鼠cDNA组成的cDNA微阵列分析了小鼠乳腺上皮细胞（NMuMG）中的表达谱，该细胞在用逆转录病毒载体中的生长抑制因子1（ING1）反义抑制剂诱导转化后。随后通过半定量逆转录PCR对所选基因表达水平变化的确认表明，反义ING1的过表达刺激了14个基因的表达，其中包括细胞周期蛋白B1、12-O-十四酰佛波醇-13-乙酸酯诱导序列11、原癌基因DEK和骨桥蛋白，而我们检测到5个基因的转录抑制，包括TPT1。此外，腺病毒介导的ING1在NMuMG细胞中的过表达导致细胞周期蛋白B1、12-O-十四酰佛波醇-13-乙酸酯诱导序列11、DEK和骨桥蛋白的下调，而TPT1表达水平增加。使用p53(-/-) SAOS2细胞的进一步分析表明，p33(ING1)诱导的细胞周期蛋白B1下调是p53依赖性的。因此，我们的cDNA微阵列分析表明，p33(ING1)靶向多个基因，包括原癌基因DEK和细胞周期蛋白B1，其中至少一些基因在经历细胞生长或凋亡的细胞中以p53依赖性方式受到调控。
