Investigation the effects of vitreous humor on proliferation and dedifferentiation of differentiated NTERA2 cells / Investigar os efeitos do humor vítreo na proliferação e desdiferenciação de células NTERA2 diferenciadas

Abstract Mammals have a limited capacity to regenerate their tissues and organs. One of the mechanisms associated with natural regeneration is dedifferentiation. Several small molecules such as vitamin C and growth factors could improve reprogramming efficiency. In this study, the NTERA2-D1 (NT2) cells were induced towards differentiation (NT2-RA) with 10-5 M retinoic acid (RA) for three days and then subjected to various amounts of vitreous humor (VH). Results show that the growth rate of these cells was reduced, while this rate was partly restored upon treatment with VH (NT2-RA-VH). Cell cycle analysis with PI method also showed that the numbers of cells at the S phase of the cell cycle in these cells were increased. The levels of SSEA3 and TRA-1-81 antigens in NT2-RA were dropped but they increased in NT2- RA-VH to a level similar to the NT2 cells. The level of SSEA1 had an opposite pattern. Expression of OCT4 gene dropped after RA treatment, but it was recovered in NT2-RA-VH cells. In conclusion, we suggest VH as a potent mixture for improving the cellular reprogramming leading to dedifferentiation.

Resumo Os mamíferos têm uma capacidade limitada de regenerar seus tecidos e órgãos. Um dos mecanismos associados à regeneração natural é a desdiferenciação. Várias moléculas pequenas, como vitamina C e fatores de crescimento, podem melhorar a eficiência da reprogramação. Neste estudo, as células NTERA2-D1 (NT2) foram induzidas à diferenciação (NT2-RA) com ácido retinóico (RA) 10-5 M por três dias e depois submetidas a várias quantidades de humor vítreo (VH). Os resultados mostram que a taxa de crescimento dessas células foi reduzida, enquanto essa taxa foi parcialmente restaurada após o tratamento com VH (NT2-RA-VH). A análise do ciclo celular com o método PI também mostrou que o número de células na fase S do ciclo celular nessas células estava aumentado. Os níveis de antígenos SSEA3 e TRA-1-81 em NT2-RA diminuíram, mas aumentaram em NT2-RA-VH a um nível semelhante ao das células NT2. O nível de SSEA1 teve um padrão oposto. A expressão do gene OCT4 diminuiu após o tratamento com AR, mas foi recuperado em células NT2-RA-VH. Em conclusão, sugerimos o VH como uma mistura potente para melhorar a reprogramação celular levando à desdiferenciação.

Lipossarcoma Bem Diferenciado do Retroperitônio com Desdiferenciação e Múltiplas Recidivas: Relato de Caso / Well-Differentiated Liposarcoma of the Retroperitoneum with Dedifferentiation and Multiple Recurrences: Case Report / Liposarcoma Bien Diferenciado de Retroperitoneo con Desdiferenciación y Múltiples Recurrencias: Informe de Caso

Introdução: Os lipossarcomas retroperitoneais são neoplasias mesenquimais raras, sendo mais comuns os bem diferenciados e os desdiferenciados. O subtipo bem diferenciado pode sofrer desdiferenciação para tumores de maior grau. São neoplasias difíceis de tratar cirurgicamente, pois apresentam altas taxas de recorrência local, alguns subtipos podem metastizar e são pouco sensíveis à radioterapia e à quimioterapia. Relato do caso: Paciente feminina, 45 anos, apresentou dor abdominal e massa abdominal palpável em 2017. Foi submetida à ressecção de lipossarcoma bem diferenciado de retroperitônio, sem intercorrências. Em 2020, manifestou dor abdominal e perda ponderal. A tomografia mostrou múltiplas massas volumosas abdominais, com biópsia sugestiva de lipossarcoma desdiferenciado. Foi submetida à radioterapia neoadjuvante e, em seguida, à ressecção cirúrgica das massas e ileocolectomia direita. Em 2022, apresentou quadro sugestivo de obstrução intestinal, sendo submetida à laparotomia que evidenciou intenso bloqueio de alças intestinais, fístula duodenal, tumor retroperitonial e peritonite fecal. Procedeu-se à ressecção de neoplasia retroperitoneal, ileostomia e rafia de fístula. O histopatológico mostrou lipossarcoma desdiferenciado recidivado. A paciente evoluiu com complicações operatórias e infecciosas, necessitando de cuidados intensivos e antibioticoterapia. Após melhora clínica, recebeu alta com dieta enteral e segue em acompanhamento ambulatorial. Conclusão: O lipossarcoma de retroperitônio pode sofrer desdiferenciação, recidivas multifocais e múltiplas recorrências, necessitando de várias abordagens cirúrgicas, o que aumenta a morbidade e o risco de complicações. A cirurgia com margens amplas continua sendo a principal modalidade terapêutica.

ABSTRACT Introduction: Retroperitoneal liposarcomas are rare mesenchymal neoplasms, with well-differentiated and dedifferentiated liposarcomas being most common. The well differentiated subtype can undergo dedifferentiation to higher grade tumors. These are difficult neoplasms to treat surgically because they have high rates of local recurrence, some subtypes can metastasize, and are poorly responsive to radiotherapy and chemotherapy. Case report: Female patient, 45 years old, presented abdominal pain and palpable abdominal mass in 2017. She underwent resection of well-differentiated liposarcoma of the retroperitoneum, without intercurrences. In 2020, she manifested abdominal pain and weight loss. Tomography showed multiple voluminous abdominal masses, with biopsy suggestive of dedifferentiated liposarcoma. The patient was submitted to neoadjuvant radiotherapy, followed by surgical resection of the masses and right ileocolectomy. In 2022, she presented symptoms suggestive of intestinal obstruction, and underwent laparotomy that revealed intense blockage of intestinal loops, duodenal fistula, retroperitoneal tumor, and fecal peritonitis. Retroperitoneal neoplasm resection, ileostomy and fistula closure were performed. Histopathology showed relapsed dedifferentiated liposarcoma. The patient evolved with operative and infectious complications, requiring intensive care and antibiotic therapy. After clinical improvement, the patient was discharged with enteral diet and continues under outpatient follow-up. Conclusion: Retroperitoneal liposarcoma may undergo multifocal dedifferentiation and recurrence, requiring several surgical approaches, increasing morbidity and the risk of complications. Wide margin surgery remains the main therapeutic modality.

Introducción: Los liposarcomas retroperitoneales son neoplasias mesenquimatosas raras, siendo los más comunes los liposarcomas bien diferenciados y desdiferenciados. El subtipo bien diferenciado puede sufrir desdiferenciación hacia tumores de mayor grado. Estas neoplasias son difíciles de tratar quirúrgicamente porque presentan altas tasas de recidiva local, algunos subtipos pueden hacer metástasis y responden mal a la radioterapia y la quimioterapia. Informe del caso: Mujer de 45 años, en 2017 presenta dolor abdominal y masa abdominal palpable. Fue sometida a la resección de un liposarcoma bien diferenciado del retroperitoneo, sin intercurrencias. En 2020, manifestó dolor abdominal y pérdida de peso. La tomografía mostró múltiples masas abdominales voluminosas, con biopsia sugestiva de liposarcoma desdiferenciado. Fue sometida a radioterapia neoadyuvante y luego a resección quirúrgica de las masas y a ileocolectomía derecha. En 2022, presentó síntomas de obstrucción intestinal y fue sometida a una laparotomía que reveló obstrucción de las asas intestinales, fístula duodenal, tumor retroperitoneal y peritonitis fecal. Se realizó la resección de la neoplasia retroperitoneal, la ileostomía y la fistulización. La histopatología mostró un liposarcoma desdiferenciado. La paciente evolucionó con complicaciones operatorias e infecciosas, requiriendo cuidados intensivos y terapia antibiótica. Tras la mejora clínica, la paciente fue dada de alta con dieta enteral y está en seguimiento. Conclusión: El liposarcoma retroperitoneal puede sufrir desdiferenciación multifocal y recurrencia, requiriendo varios a tratamientos quirúrgicos, aumentando la morbilidad y el riesgo de complicaciones. La cirugía con márgenes amplios sigue siendo la terapia principal.

Metástasis pancreática, sitio inusual de diseminación por cáncer de tiroides. Documentada por PET CT/FDG y estudio histopatológico / Pancreatic metastasis, an unusual site for thyroid cancer spread. Documented by PET CT/FDG and histopathology

El cáncer diferenciado de tiroides (CDT) es la neoplasia endocrina maligna encontrada con mayor frecuencia, generalmente tiene un comportamiento lento en su evolución permitiendo realizar manejo quirúrgico y terapia ablativa con Iodo 131, lográndose la remisión completa en la gran mayoría de los casos. Un pequeño porcentaje de estas neoplasias presenta un comportamiento agresivo al registrar metástasis a distancia con localización principalmente en pulmón, hueso y cerebro y con focos de desdiferenciación celular, lo cual empobrece su pro nóstico y limita las opciones terapéuticas en este tipo de tumores. En el proceso de seguimiento del CDT, la tomografia por emisión de positrones con análogo de glucosa (PET/CT con F18-FDG) se ha constituido en una herramienta diagnóstica y pronóstica de imagen eficaz. Presentamos el caso de un paciente masculino de 50 años de edad con cáncer papilar de tiroides y enfermedad metastásica en páncreas, sitio inusual de diseminación para esta patología.

Differentiated Thyroid Cancer (DTC) is the most frequently found malignant endocrine neoplasia. It is usually slow developing, allowing for surgical management and ablation therapy with Iodine 131, achieving complete remission in the great majority of cases. However, a small percentage of tumours are aggressive, with distant metastases to lung, bone, brain, and foci of cellular dedifferentiation, which worsens prognosis and limits therapeutic options. In the monitoring process of the CDT, Positron emission tomography with glucose analogue (PET/CT with F18 - FDG) remains an important diagnostic and prognostic imaging tool. The case is presented of a 50 year old male patient with papillary thyroid cancer and metastatic disease in the pancreas, an unusual site in this disease.

Effect of JJYMD-C, a novel synthetic derivative of gallic acid, on proliferation and phenotype maintenance in rabbit articular chondrocytes in vitro

Tissue engineering encapsulated cells such as chondrocytes in the carrier matrix have been widely used to repair cartilage defects. However, chondrocyte phenotype is easily lost when chondrocytes are expanded in vitro by a process defined as “dedifferentiation”. To ensure successful therapy, an effective pro-chondrogenic agent is necessary to overcome the obstacle of limited cell numbers in the restoration process, and dedifferentiation is a prerequisite. Gallic acid (GA) has been used in the treatment of arthritis, but its biocompatibility is inferior to that of other compounds. In this study, we modified GA by incorporating sulfamonomethoxine sodium and synthesized a sulfonamido-based gallate, JJYMD-C, and evaluated its effect on chondrocyte metabolism. Our results showed that JJYMD-C could effectively increase the levels of the collagen II, Sox9, and aggrecan genes, promote chondrocyte growth, and enhance secretion and synthesis of cartilage extracellular matrix. On the other hand, expression of the collagen I gene was effectively down-regulated, demonstrating inhibition of chondrocyte dedifferentiation by JJYMD-C. Hypertrophy, as a characteristic of chondrocyte ossification, was undetectable in the JJYMD-C groups. We used JJYMD-C at doses of 0.125, 0.25, and 0.5 µg/mL, and the strongest response was observed with 0.25 µg/mL. This study provides a basis for further studies on a novel agent in the treatment of articular cartilage defects.

Distribution of linker histone variants during plant cell differentiation in the developmental zones of the maize root, dedifferentiation in callus culture after auxin treatment

Although several linker histone variants have been studied in both animal and plant organisms, little is known about their distribution during processes that involve alterations in chromatin function, such as differentiation, dedifferentiation and hormone treatment. In this study, we identified linker histone variants by using specific anti-histone Hl antibodies. Each variant's ratio to total Hl in the three developmental zones of maize (Zea mays L.) root and in callus cultures derived from them was estimated in order to define possible alterations either during plant cell differentiation or during their dedifferentiation. We also evaluated linker histone variants' ratios in the developmental zones of maize roots treated with auxin in order to examine the effects of exogenous applied auxin to linker histone variant distribution. Finally, immunohistochemical detection was used to identify the root tissues containing each variant and correlate them with the physiological status of the plant cells. According to the results presented in this study, linker histone variants' ratios are altered in the developmental zones of maize root, while they are similar to the meristematic zone in samples from callus cultures and to the differentiation zone in samples from roots treated with auxin. We propose that the alterations in linker histone variants' ratios are correlated with plant cell differentiation and dedifferentiation.