RESUMO
AIM: To demonstrate a rare case of ciliary body leiomyoma in our patient Case report: A 72-year-old female reported to our clinic for a preventive examination, upon which we found a dome-shaped grey-brownish mass on the retinal periphery. After completing gonioscopic and ultrasound examinations, we referred the patient to a specialist facility. Due to a finding of suspicious malignant melanoma, we completed the MRI scan and recommended enucleation of the eyeball. A histopathological examination showed a leiomyoma of the ciliary body. CONCLUSION: The aim of this case report is to demonstrate the difficulty of intraocular leiomyoma diagnosis. Only immunohistochemical examination differentiated the tumor from malignant melanoma and determined the diagnosis of ciliary body leiomyoma. Perhaps because of the extreme rarity of this type of tumor, we often neglect to consider a diagnosis of leiomyoma.
Assuntos
Corpo Ciliar , Leiomioma , Neoplasias Uveais , Humanos , Leiomioma/patologia , Leiomioma/diagnóstico por imagem , Leiomioma/diagnóstico , Leiomioma/cirurgia , Feminino , Corpo Ciliar/patologia , Corpo Ciliar/diagnóstico por imagem , Idoso , Neoplasias Uveais/patologia , Neoplasias Uveais/diagnóstico por imagem , Neoplasias Uveais/diagnóstico , Neoplasias Uveais/cirurgia , Melanoma/patologia , Melanoma/diagnóstico por imagem , Melanoma/diagnóstico , Melanoma/cirurgia , Diagnóstico DiferencialRESUMO
Replication stress (RS) has a pivotal role in tumor initiation, progression, or therapeutic resistance. In this study, we depicted the mechanism of breast cancer stem cells' (bCSCs) response to RS and its clinical implication. We demonstrated that bCSCs present a limited level of RS compared with non-bCSCs in patient samples. We described for the first time that the spatial nuclear location of BMI1 protein triggers RS response in breast cancers. Hence, in bCSCs, BMI1 is rapidly located to stalled replication forks to recruit RAD51 and activate homologous-recombination machinery, whereas in non-bCSCs BMI1 is trapped on demethylated 1q12 megasatellites precluding effective RS response. We further demonstrated that BMI1/RAD51 axis activation is necessary to prevent cisplatin-induced DNA damage and that treatment of patient-derived xenografts with a RAD51 inhibitor sensitizes tumor-initiating cells to cisplatin. The comprehensive view of replicative-stress response in bCSC has profound implications for understanding and improving therapeutic resistance.