Antonio-Véjar Verónica, Ortiz-Sánchez Elizabeth, Rosendo-Chalma Pedro, Patiño-Morales Carlos C, Guido-Jiménez Miriam C, Alvarado-Ortiz Eduardo, Hernández Greco, García-Carrancá Alejandro
Programa de Doctorado en Ciencias Biomédicas, Universidad Nacional Autónoma de México (UNAM), Ciudad de México, 10450, Mexico; Laboratorio de Biomedicina Molecular, Facultad de Ciencias Químico Biológicas, Universidad Autónoma de Guerrero, Chilpancingo, 39090, Guerrero, Mexico; Unidad de Investigación Biomédica en Cáncer, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México and Instituto Nacional de Cancerología, Ciudad de México, 14080, Mexico.
Subdirección de Investigación Básica, Instituto Nacional de Cancerología, Ciudad de México, 14080, Mexico.
Pathol Res Pract. 2022 Jun;234:153890. doi: 10.1016/j.prp.2022.153890. Epub 2022 Apr 9.
An important characteristic of cancers associated with high-risk human papillomaviruses (HR-HPV) is the inability of p53 to activate apoptosis due to the effect of the oncoprotein E6. However, the effect of HPV-16 E6 splice variant isoforms (namely E6I and E6II), their interaction with the existing p53 isoforms, and their influence on apoptosis is unclear. Here, we report the outcome of ectopic expression of HPV-16 E6, E6I, and E6II on the relative levels of p53 and p53 isoforms Δ40p53 and Δ133p53 and their interactions with these proteins. Additionally, we evaluated the effect of ectopic expression of p53, Δ40p53, and Δ133p53 on apoptosis in a p53 null pulmonary cell line (H1299) co-transfected with E6 isoforms and p53 cell lines with HR-HPV (SiHa and HeLa), transfected with p53 isoforms and treated with cisplatin, a conventional drug used to treat cervical cancer. Our results show that E6 and E6II induced a significant decrease in p53, but only E6 triggered a Δ40p53 decrease and that E6II interacts with p53 but not with Δ40p53 and Δ133p53. On the other hand, E6*I did not show any effect or interaction with the p53 isoforms. We found that apoptosis was elevated in H1299 cells transfected with p53 (p = 0.0001) and Δ40p53 (p = 0.0001). A weak apoptotic effect was observed when Δ133p53 was ectopically expressed (p = 0.0195). We observed that both p53 (p = 0.0006) and Δ40p53 (p = 0.0014) induced apoptosis in cisplatin-treated SiHa cells; however in cisplatin-treated HeLa cells, only p53 induced apoptosis (p = 0.0029). No significant differences in apoptosis were observed upon ectopic expression of p53, Δ40p53, and Δ133p53 in SiHa and HeLa cells. Our findings suggest a possible therapeutic application for the combining of p53 or Δ40p53 with cisplatin to induce an increased apoptosis of cancer cells expressing E6 isoforms from HPV-16.
与高危型人乳头瘤病毒（HR-HPV）相关的癌症的一个重要特征是，由于癌蛋白E6的作用，p53无法激活细胞凋亡。然而，HPV-16 E6剪接变体亚型（即E6I和E6II）的作用、它们与现有p53亚型的相互作用以及它们对细胞凋亡的影响尚不清楚。在此，我们报告了HPV-16 E6、E6I和E6II异位表达对p53及p53亚型Δ40p53和Δ133p53相对水平的影响，以及它们与这些蛋白质的相互作用。此外，我们评估了p53、Δ40p53和Δ133p53异位表达对p53基因缺失的肺细胞系（H1299）细胞凋亡的影响，该细胞系与E6亚型共转染，还有对HR-HPV阳性的p53细胞系（SiHa和HeLa）的影响，这些细胞系转染了p53亚型并用顺铂处理，顺铂是一种用于治疗宫颈癌的传统药物。我们的结果表明，E6和E6II可导致p53显著减少，但只有E6能引发Δ40p53减少，且E6II与p53相互作用，但不与Δ40p53和Δ133p53相互作用。另一方面，E6*I对p53亚型未显示任何作用或相互作用。我们发现，转染p53（p = 0.0001）和Δ40p53（p = 0.0001）的H1299细胞中细胞凋亡增加。异位表达Δ133p53时观察到微弱的凋亡效应（p = 0.0195）。我们观察到，p53（p = 0.0006）和Δ40p53（p = 0.0014）均可在顺铂处理的SiHa细胞中诱导细胞凋亡；然而，在顺铂处理的HeLa细胞中，只有p53可诱导细胞凋亡（p = 0.0029）。在SiHa和HeLa细胞中异位表达p53、Δ40p53和Δ133p53后，未观察到细胞凋亡的显著差异。我们的研究结果表明，p53或Δ40p53与顺铂联合使用可能具有治疗应用价值，可诱导表达HPV-16 E6亚型的癌细胞增加凋亡。
