Mutant p53 reactivation restricts the protumorigenic consequences of wild type p53 loss of heterozygosity in Li-Fraumeni syndrome patient-derived fibroblasts.

The p53 tumor suppressor, encoded by the TP53 gene, serves as a major barrier against malignant transformation. Patients with Li-Fraumeni syndrome (LFS) inherit a mutated TP53 allele from one parent and a wild-type TP53 allele from the other. Subsequently, the wild-type allele is lost and only the mutant TP53 allele remains. This process, which is termed loss of heterozygosity (LOH), results in only mutant p53 protein expression. We used primary dermal fibroblasts from LFS patients carrying the hotspot p53 gain-of-function pathogenic variant, R248Q to study the LOH process and characterize alterations in various pathways before and after LOH. We previously described the derivation of mutant p53 reactivating peptides, designated pCAPs (p53 Conformation Activating Peptides). In this study, we tested the effect of lead peptide pCAP-250 on LOH and on its associated cellular changes. We report that treatment of LFS fibroblasts with pCAP-250 prevents the accumulation of mutant p53 protein, inhibits LOH, and alleviates its cellular consequences. Furthermore, prolonged treatment with pCAP-250 significantly reduces DNA damage and restores long-term genomic stability. pCAPs may thus be contemplated as a potential preventive treatment to prevent or delay early onset cancer in carriers of mutant p53.

Angiosarcoma in previously irradiated breast in patient with Li-Fraumeni syndrome. A case report / Angiossarcoma em mama previamente irradiada em paciente portadora da síndrome de Li-Fraumeni. Um relato de caso

CONTEXT: Li-Fraumeni syndrome is a rare disease with an autosomal dominant inheritance pattern and high penetrance that defines a 50% chance of developing cancer before the age of 30 years, including cases of breast sarcoma. Patients with this syndrome who require radiotherapy have an increased risk of developing secondary malignancies including angiosarcomas. CASE REPORT: This was a case report on a female patient with Li-Fraumeni syndrome. In October 2005, she was diagnosed with invasive ductal carcinoma of the right breast and underwent sectorectomy. She then received chemotherapy and adjuvant radiotherapy. Trastuzumab and tamoxifen were also part of the treatment. She recently sought care at our hospital, complaining of hyperemia and nodulation in the right breast, and underwent surgical resection that revealed epithelioid angiosarcoma. CONCLUSIONS: When genetic predisposition due to Li-Fraumeni syndrome is documented, the therapy should be adapted so as to minimize the risk. Thus, conservative surgical treatments should be avoided and mastectomy without radiation should be prioritized. In cases in which use of radiotherapy is justified, patients should be followed up intensively. .

CONTEXTO: A síndrome de Li-Fraumeni é doença rara que apresenta padrão de herança autossômica dominante e alta penetrância, definindo possibilidade de 50% no desenvolvimento de neoplasias antes dos 30 anos, incluindo nesses casos os sarcomas em mama. Pacientes portadoras dessa síndrome que requerem tratamento radioterápico têm risco aumentado de desenvolver neoplasias secundárias, incluindo os angiossarcomas. RELATO DE CASO: Este é um relato de caso de paciente feminina, portadora da síndrome de Li-Fraumeni. Em outubro de 2005, ela teve diagnóstico de carcinoma ductal invasor da mama direita, sendo submetida à setorectomia. Recebeu quimioterapia e radioterapia adjuvante; trastuzumabe e tamoxifeno também fizeram parte do tratamento. Recentemente, procurou atendimento em nosso serviço, com queixa de hiperemia e nodulação em mama direita, e foi submetida a ressecção cirúrgica que revelou angiossarcoma epitelioide. CONCLUSÕES: Quando a predisposição genética da síndrome de Li-Fraumeni está documentada, devese adequar a terapêutica a fim de minimizar riscos, evitando tratamentos cirúrgicos conservadores e priorizando a mastectomia sem radioterapia. Nos casos em que se justifica o uso de radioterapia, os pacientes devem ser acompanhados de forma intensiva. .

Tumoración pélvica en una paciente con síndrome de li fraumeni / Pelvic tumor in a patient with li-fraumeni syndrome

El síndrome de Li Fraumeni (SLF) es una rara enfermedad hereditaria asociada con un riesgo incrementado de padecer ciertos tumores malignos. Presentamos el caso de una paciente con diagnóstico de SLF con antecedentes de sarcoma de glúteo con metástasis pulmonares y cáncer de mama bilateral metacrónico. Acudió al Servicio de Urgencias por distensión y dolor abdominal. Se objetivó una masa pélvica y se pensó en un probable origen ovárico de la misma. La paciente fue intervenida en el Servicio de Ginecología, y durante la intervención se descartó dicho origen ya que la tumoración dependía del epiplón. El diagnóstico final fue metástasis de sarcoma.

Li-Fraumeni syndrome (LFS) is a rare, inherited syndrome associated with increased risk of various malignant tumors. We present the case of a patient diagnosed LSF with a history of gluteal sarcoma with lung metastases and metachronous bilateral breast cáncer. She came to the emergency department for abdominal bloating and pain. She had a pelvic mass and we had thought probable ovarian dependence. The patient was operated on at the Department of Gynecology, and during the intervention we realized that the tumor depended on the omentum. The final diagnosis was a metastatic of sarcoma.