Спектр мутаций гена VHL при спорадическом светлоклеточном почечно-клеточном раке

The VHL gene alterations are the early and characteristic feature of clear cell renal cell carcinoma (ccRCC). We have examined VHL mutations in sporadic 98 ccRCC cases to evaluate their localization in relation to functionally important motifs of the VHL protein. The DNA samples were obtained from snap-frozen carcinoma biopsies and used for Sanger sequencing, while 62 ccRCC DNA cases were studied by next generation sequencing (NGS) analysis in parallel. In 73 (74.4 %) оf 98 ccRCC cases the somatic non-silent VHL mutations were identified. Loss of function VHL mutations (nonsilent, frameshifts or in splicing sites) were detected in 40 (40.8 %) ccRCC, while missense mutations – in 35 (35.7 %) ccRCC. In total 76 mutations important for VHL functioning were detected in 72 (73 %) ccRCC samples, of them 15 mutations (deletion / insertion in-frame or frameshifts) were identified for the first time. Four ccRCC cases contained two mutations each. Most of missense mutations disturb the sites of VHL interactions with HIF, РКС or kinesin. The pathogenicity of p.P154P silent mutation and intronic mutations near mRNA VHL splicing sites was discussed. The obtained results are important for understanding the role of VHL mutations in ccRCC progression and prognosis.Нарушения гена VHL являются ранней и характерной особенностью светлоклеточного почечно-клеточного рака (скПКР). Проведен анализ мутаций VHL в 98 образцах скПКР для определения их локализации относительно функционально значимых мотивов белка VHL. Анализ мутаций VHL проводили в ДНК из свежезамороженных тканей опухоли секвенированием по Сэнгеру, параллельно 62 образца скПКР подвергли cеквенированию нового поколения (next generation sequencing, NGS). В 73 (74,4 %) из 98 образцов скПКР обнаружены нон-сайлент-мутации в кодирующей части гена VHL. Мутации, нарушающие функции белка VHL (нонсенс-мутации, мутации в сайтах сплайсинга и делеции / инсерции со сдвигом рамки считывания), выявлены в 40 (40,8 %) образцах скПКР, миссенс-мутации – в 35 (35,7 %). Всего обнаружено 76 мутаций, влияющих на функции белка VHL в 72 (73 %) образцах скПКР, причем 15 мутаций не были описаны ранее (делеции / инсерции VHL со сдвигом или без сдвига рамки считывания). В 4 случаях скПКР выявлено по 2 мутации VHL. Большинство миссенс-мутаций нарушают сайты взаимодействия белка VHL с HIF, РKС или кинезином. Рассмотрен вопрос о патогенности сайлент-мутации p.P154P и мутаций в интронах вблизи сайтов сплайсинга. Полученные результаты важны для изучения роли мутаций VHL в прогрессировании и прогнозе скПКР

Spectrum of VHL mutations in clear cell renal cell carcinoma

The VHL gene alterations are the early and characteristic feature of clear cell renal cell carcinoma (ccRCC). We have examined VHL mutations in sporadic 98 ccRCC cases to evaluate their localization in relation to functionally important motifs of the VHL protein. The DNA samples were obtained from snap-frozen carcinoma biopsies and used for Sanger sequencing, while 62 ccRCC DNA cases were studied by next generation sequencing (NGS) analysis in parallel. In 73 (74.4 %) оf 98 ccRCC cases the somatic non-silent VHL mutations were identified. Loss of function VHL mutations (nonsilent, frameshifts or in splicing sites) were detected in 40 (40.8 %) ccRCC, while missense mutations – in 35 (35.7 %) ccRCC. In total 76 mutations important for VHL functioning were detected in 72 (73 %) ccRCC samples, of them 15 mutations (deletion / insertion in-frame or frameshifts) were identified for the first time. Four ccRCC cases contained two mutations each. Most of missense mutations disturb the sites of VHL interactions with HIF, РКС or kinesin. The pathogenicity of p.P154P silent mutation and intronic mutations near mRNA VHL splicing sites was discussed. The obtained results are important for understanding the role of VHL mutations in ccRCC progression and prognosis