Department of Toxicology, School of Public Health, Southern Medical University (Guangdong Provincial Key Laboratory of Tropical Disease Research), 1023 S. Shatai Road, Guangzhou, 510515, China.
Department of Toxicology, School of Public Health, Southern Medical University (Guangdong Provincial Key Laboratory of Tropical Disease Research), 1023 S. Shatai Road, Guangzhou, 510515, China.
Chem Biol Interact. 2020 Dec 1;332:109283. doi: 10.1016/j.cbi.2020.109283. Epub 2020 Oct 6.
1-Methylpyrene (1-MP) is a ubiquitous environmental pollutant and rodent carcinogen. Its mutagenic activity depends on sequential activation by various CYP and sulfotransferase (SULT) enzymes. Previously we have observed induction of micronuclei and mitotic arrest by 1-MP in a Chinese hamster (V79)-derived cell line expressing both human CYP1A2 and SULT1A1 (V79-hCYP1A2-hSULT1A1), however, the mode of chromosome damage and the involvement of mitotic tubulin structures have not been clarified. In this study, we used immunofluorescent staining of centromere protein B (CENP-B) with the formed micronuclei, and that of β- and γ-tubulin reflecting the structures of mitotic spindle and centrioles, respectively, in V79-hCYP1A2-hSULT1A1 cells. The results indicated that 1-MP induced micronuclei in V79-hCYP1A2-hSULT1A1 cells from 0.125 to 2 μM under a 24 h/0 h (exposure/recovery) regime, while in the parental V79-Mz cells micronuclei were induced by 1-MP only at concentrations ≥ 8 μM; in both cases, the micronuclei induced by 1-MP were predominantly CENP-B positive. Following 54 h of exposure, 1-MP induced mitotic spindle non-congression and centrosome amplification (multipolar mitosis) in V79-hCYP1A2-hSULT1A1 cells, and anaphase/telophase retardation, at concentrations ≥ 0.125 μM with concentration-dependence; while in V79-Mz cells it was inactive up to 8 μM. This study suggests that in mammalian cells proficient in activating enzymes 1-MP may induce chromosome loss and mitotic disturbance, probably by interfering with the mitotic spindle and centrioles.
1-甲基芘（1-MP）是一种普遍存在的环境污染物和啮齿动物致癌物。其致突变活性取决于各种 CYP 和磺基转移酶（SULT）酶的顺序激活。以前，我们观察到在表达人 CYP1A2 和 SULT1A1 的中国仓鼠（V79）衍生细胞系中，1-MP 诱导微核形成和有丝分裂阻滞，然而，染色体损伤的模式和有丝分裂微管结构的参与尚未阐明。在这项研究中，我们使用 centromere protein B（CENP-B）的免疫荧光染色与形成的微核，以及β-和γ-微管蛋白的免疫荧光染色，分别反映有丝分裂纺锤体和中心粒的结构，在 V79-hCYP1A2-hSULT1A1 细胞中。结果表明，在 24 小时/0 小时（暴露/恢复）的条件下，1-MP 在 0.125 至 2μM 之间诱导 V79-hCYP1A2-hSULT1A1 细胞中的微核形成，而在亲本 V79-Mz 细胞中，只有在浓度≥8μM 时，1-MP 才会诱导微核形成；在这两种情况下，1-MP 诱导的微核主要是 CENP-B 阳性。暴露 54 小时后，1-MP 在 V79-hCYP1A2-hSULT1A1 细胞中诱导有丝分裂纺锤体非聚合和中心体扩增（多极有丝分裂），并在浓度≥0.125μM 时出现后期/末期延迟，呈浓度依赖性；而在 V79-Mz 细胞中，浓度高达 8μM 时仍无活性。这项研究表明，在能够有效激活酶的哺乳动物细胞中，1-MP 可能会导致染色体丢失和有丝分裂紊乱，可能是通过干扰有丝分裂纺锤体和中心粒。
