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.

Effects of interferon regulatory factor 9 on the biological phenotypes in PML-RARα-induced promyelocytic leukemia / 中华血液学杂志

Objective: To investigate the prognostic significance of interferon regulatory factor 9 (IRF9) expression and identify its role as a potential therapeutic target in acute promyelocytic leukemia (APL) . Methods: The gene expression profile and survival data applied in the bioinformatic analysis were obtained from The Cancer Genome Atlas and Beat acute myeloid leukemia (AML) cohorts. A dox-induced lentiviral system was used to induce the expression of PML-RARα (PR) in U937 cells, and the expression level of IRF9 in U937 cells treated with or without ATRA was examined. We then induced the expression of IRF9 in NB4, a promyelocytic leukemia cell line. In vitro studies focused on leukemic phenotypes triggered by IRF9 expression. Results: ①Bioinformatic analysis of the public database demonstrated the lowest expression of IRF9 in APL among all subtypes of AML, with lower expression associated with worse prognosis. ②We successfully established a PR-expression-inducible U937 cell line and found that IRF9 was downregulated by the PR fusion gene in APL, with undetectable expression in NB4 promyelocytic cells. ③An IRF9-inducible NB4 cell line was successfully established. The inducible expression of IRF9 promoted the differentiation of NB4 cells and had a synergistic effect with lower doses of ATRA. In addition, the inducible expression of IRF9 significantly reduced the colony formation capacity of NB4 cells. Conclusion: In this study, we found that the inducible expression of PR downregulates IRF9 and can be reversed by ATRA, suggesting a specific regulatory relationship between IRF9 and the PR fusion gene. The induction of IRF9 expression in NB4 cells can promote cell differentiation as well as reduce the colony forming ability of leukemia cells, implying an anti-leukemia effect for IRF9, which lays a biological foundation for IRF9 as a potential target for the treatment of APL.

The Effects of Decitabine Combined with All-Trans Retinoic Acid on the Number of Immune Cells in Myeloid Neoplasms / 中国实验血液学杂志

OBJECTIVE@#To investigate the effects of decitabine (DEC) combined with all-trans retinoic acid (ATRA) on the number of immune cells, efficacy and adverse reactions in the treatment of myeloid neoplasms patients.@*METHODS@#Eighty-four patients with myeloid tumors, including AML, MDS-EB-1 or MDS-EB-2 treated by the regimen containing decitabine in our hospital from January 2009 to October 2019 were enrolled and retrospectively analyzed, among the patients, 21 patients treated with DEC alone, 24 patients treated with DEC combined with ATRA (DEC/ATRA) and 39 patients treated with DEC combined with G-CSF priming regimen (DEC/priming). The changes of peripheral blood immune cell levels before and after treatment of the patients between the three groups were compared, and the differences in clinical efficacy and adverse reactions of the patients between the three groups were also compared.@*RESULTS@#There was no statistical differences in the number of immune cells among the patients in the three groups before treatment (P>0.05). NK cell levels decreased significantly in the patients in DEC and DEC/ATRA group after treatment (P<0.05); After treatment, the levels of CD8+ and CD3+T cells in the patients treated by DEC /priming regimen significantly increased (P<0.05), while the levels of CD3-HLA-DR+ B cells significantly decreased (P<0.05). The overall response rate (ORR) of the patients in DEC/ATRA group (75%) and DEC/priming group (74.36%) was significantly higher than 42.86% in DEC monotherapy group, and the differences showed statistically significant (P<0.05), while the ORR between the patients in DEC/ATRA and DEC/priming group showed no statistic differences (P>0.05). There were no statistical differences in overall survival (OS) and incidence of bleeding between the patients in the three groups (P>0.05). The incidences of grade 3 to 4 bone marrow suppression and the infection rate of the patients in DEC monotherapy and DEC/ATRA group were significantly lower than that in DEC/priming regimen group after treatment (all P<0.05), however, there was no statistical difference between DEC monotherapy and the DEC/ATRA group.@*CONCLUSION@#The efficacy of DEC/ATRA on myeloid neoplasms is comparable to that of DEC/priming regimen, and the anti-myeloid tumor effect of DEC/ATRA regimen may be related to the regulation of NK cells and T cells.

Caracterización clínica y citogenética de una cohorte de pacientes con leucemia promielocítica aguda atendidos en un Hospital Universitario en Medellín, Colombia / Clinical and cytogenetic characterization of a cohort of patients with acute promyelocytic leukemia treated at a University Hospital in Medellín, Colombia

Introducción. La leucemia promielocítica aguda (LPA) es un subtipo poco frecuente de leucemia mieloide aguda (LMA), que se caracteriza por un comportamiento clínico particularmente agresivo, y en ausencia de tratamiento, su curso generalmente es fatal. El objetivo de este trabajo fue determinar las características clínicas y citogenéticas de una cohorte de pacientes con LPA, con la finalidad de evaluar su relación con las complicaciones, el pronóstico y el desenlace de estos pacientes. Metodología. Se realizó un estudio observacional, descriptivo, retrospectivo de los pacientes mayores de 15 años con diagnóstico de LPA, atendidos en el Hospital Universitario San Vicente Fundación, entre los años 2012 a 2020. Resultados. Un total de 32 pacientes fueron incluidos. La edad media del diagnóstico fue 37 años. El 84,4% de los pacientes tenía la traslocación (15;17) en el cariotipo, y el 93,75% tenían FISH positivo. El 12,5% de los casos tenían cariotipo complejo. La mortalidad en los primeros 30 días fue del 15,6%, siendo el sangrado la causa de muerte más frecuente. Todos los pacientes que sobrevivieron alcanzaron la remisión completa (84,3%). En un promedio de seguimiento de 24 meses, el 14,8% de los casos recayeron. En el análisis bivariado se encontró relación entre sexo masculino y tener cariotipo complejo (p=0,015). No se encontró relación entre cariotipo complejo y mortalidad temprana (p=0,358), tampoco entre cariotipo complejo y recaída (p=0,052). Conclusiones. Se presentan las características clínicas y citogenéticas de una cohorte de pacientes con LPA en Colombia. El sangrado en el sistema nervioso central fue la principal causa de mortalidad temprana, todos los pacientes que sobrevivieron alcanzaron la remisión completa con la terapia de inducción. Las tasas de mortalidad, remisión completa y recaída fueron similares a las reportadas por otras series latinoamericanas, pero inferiores a estudios provenientes de países europeos. Contrario a lo reportado en otros estudios, no se encontró relación entre el cariotipo complejo y la mortalidad temprana o recaída.

Introduction. Acute promyelocytic leukemia (APL) is a rare subtype of acute myeloid leukemia (AML), characterized by a particularly aggressive clinical behavior, that in the absence of treatment is usually fatal. The objective of this work was to determine the clinical and cytogenetic characteristics of a cohort of patients with APL, in order to evaluate their relationship with the outcome and prognosis of these patients. Methodology. An observational, descriptive, retrospective study of patients older than 15 years with a diagnosis of APL treated at the Hospital Universitario San Vicente Fundación, between 2012 and 2020, was carried out. Results. A total of 32 patients were included. The mean age at diagnosis was 37 years, 84.4% of the patients had the t(15;17) in the karyotype, and 93.75% had positive FISH. 12.5% of cases had a complex karyotype. Mortality in the first 30 days was 15.6%, with bleeding being the most common cause of death. All patients who survived achieved complete remission (84.3%). In an average follow-up of 24 months, 14.8% of cases relapsed. In the bivariate analysis, a relationship was found between the male sex and having a complex karyotype (p<0.015). No relationship was found between complex karyotype and early mortality (p=0.358), nor between complex karyotype and relapse (p=0.052). Conclusions. We present the clinical and cytogenetic characteristics of a cohort of patients with APL in Colombia. Central nervous system bleeding was the main cause of early mortality, with all surviving patients achieving complete remission on induction therapy. Mortality, complete remission and relapse rates were similar to those reported by other Latin American series, but lower than studies from European countries. Contrary to what has been reported in other studies, no relationship was found between complex karyotype and early mortality or relapse

Cost-effectiveness of the regimen proposed by the International Consortium on Acute Promyelocytic Leukemia for the treatment of newly diagnosed patients with Acute Promyelocytic Leukemia

ABSTRACT Introduction: We performed cost-effectiveness and cost-utility analyses of the modified International Consortium on Acute Promyelocytic Leukemia protocol in Mexico for the treatment of acute promyelocytic leukemia Acute Promyelocytic Leukemia. Methods: We performed a three-state Markov analysis: stable disease (first line complete response [CR]), disease event (relapse, second line response and CR) and death. The modified IC-APL protocol is composed of three phases: induction, consolidation and maintenance. Cost and outcomes were used to calculate incremental cost-effectiveness ratios (ICERs); quality-adjusted life-years were used to calculate incremental cost-utility ratios (ICURs). Results: The CR was achieved in 18 patients (90%), treated with the IC-APL protocol as the first-line option; one patient (5%) died in induction, another one never achieved CR (5%); of the 18 patients that achieved CR, 1 relapsed (5.5%). The median treatment cost of the IC-APL protocol was $21,523 USD. The average life-year in our study was 7.8 years, while the average quality-adjusted life-year (QALY) was 6.1 years. When comparing the ICER between the IC-APL and the all-trans retinoic acid (ATRA) plus arsenic trioxide (ATO) protocols, we found the different costs of $6497, $19,133 and $17,123 USD in Italy, the USA and Canada, respectively. In relation to the ICUR, we found the different costs to be $13,955 and $11,979 USD in the USA and Canada, respectively. Conclusion: Taking into account the similar response rates, lower cost and easy access to the modified IC-APL regimen, we consider it a cost-effective and cost-utility protocol, deeming it the treatment of choice for our population.

Identify Myeloid Differentiation-Related MiRNAs Response to ATRA Induction by RNA Sequencing and CRISPR/Cas9 Gene Editing / 中国实验血液学杂志

OBJECTIVE@#To identify differentiation related miRNA and evaluate roles of miRNA during ATRA induced myeloid differentiation.@*METHODS@#The small RNA sequencing was used to analyze differential expressed miRNAs in ATRA induced NB4 cells. Then the several up or down-regulated miRNA were selected as the research candidates. SgRNAs targeting the genome of each miRNA were designed and NB4 cells with inducible expression of Cas9 protein were generated. After transduced sgRNA into NB4/Cas9 cells, the mutation level by PCR and surveyor assay were evaluated. The cell differentiation level was investigated by surface CD11b expression via flow cytometry.@*RESULTS@#A total of 410 mature miRNAs which expressed in NB4 cells were detected out after treated by ATRA, 74 miRNAs were up-regulated and 55 were down-regulated miRNAs with DNA cleavage generated by CRISPR/Cas9 was assayed directly by PCR or surveyor assay, quantitative PCR showed that the expression of miRNA was downregulated, which evaluated that gene edition successfully inhibitied the expression of mature miRNA. MiR-223 knockout showed the myeloid differentation of NB4 significantly inhibitied, while miRNA-155 knockout showed the myeloid differentation of NB4 cells significantly increased.@*CONCLUSION@#CRISPR/Cas9 is a powerful tool for gene editing and can lead to miRNA knockout. Knockouts of miR-223 and miR-155 have shown a differentiation-related phenotype, and the potential mechanism is the integrative regulation of target genes.

Effect of PADI4 on the Expression of Inflammatory Cytokines During NB4 Cells Differentiation / 中国实验血液学杂志

OBJECTIVE@#To investigate the expression of peptidylarginine deiminase 4 (PADI4) during the process of differentiation into granulocyte of NB4 cells induced by all-trans-retinoic acid (ATRA) and whether PADI4 is involved in the inflammatory cytokines expression.@*METHODS@#Granulocyte differentiation model of NB4 cells induced by ATRA was established. The cell morphology changes were observed by Wright-Giemsa staining. The expression of cell differentiation marker CD11b was analyzed by flow cytometry. The mRNA and protein expression of PADI4 was detected by RT-PCR and Western blot, respectively. The expression of tumor necrosis factor (TNF) α and interleukin (IL) 1β was analyzed by ELISA, and also examined with the knockdown of PADI4 expression by siRNA.@*RESULTS@#After NB4 cells induced by ATRA, the cytoplasm increased and the ratio of nuclear to cytoplasmic was reduced. Nuclear dented, and rod-shaped nucleus, lobulated phenomenon increased (P<0.05). Flow cytometry analysis results showed that the cell surface molecule CD11b expression increased (P<0.01). RT-PCR and Western blot showed the expression of PADI4 increased at both transcriptional and translational levels during the process of the differentiation. ELISA showed TNF-α and IL-1β secretion increased in differentiated macrophages, while they could be inhibited by PADI4-specific siRNA.@*CONCLUSION@#During the differentiation into granulocyte of NB4 cells induced by ATRA, PADI4 expression increased. Furthermore, PADI4 appeared to play a critical role in inflammatory cytokines secretion.

The role of retinoic acid in the commitment to meiosis / 亚洲男科学杂志(英文版)

Male meiosis is a complex process whereby spermatocytes undergo cell division to form haploid cells. This review focuses on the role of retinoic acid (RA) in meiosis, as well as several processes regulated by RA before cell entry into meiosis that are critical for proper meiotic entry and completion. Here, we discuss RA metabolism in the testis as well as the roles of stimulated by retinoic acid gene 8 (STRA8) and MEIOSIN, which are responsive to RA and are critical for meiosis. We assert that transcriptional regulation in the spermatogonia is critical for successful meiosis.

Effects of ATRA on diabetic rats with renal ischemia-reperfusion injury

Abstract Purpose To explore the role of all-trans retinoic acid (ATRA) in renal ischemia/reperfusion injury of diabetic rats. Methods Sixty adult male rats were randomly divided into 6 groups, including sham group (S group), ischemia-reperfusion group (I/R group), ischemia-reperfusion+ATRA group (A group), diabetic group (D group), diabetic ischemia-reperfusion group (DI/R group), diabetic ischemia-reperfusion +ATRA group (DA group). The levels of creatinine (Cr), cystatin C (Cys-C) and β2-microglobulin (β2-MG) were measured. Morphology of renal tissue was observed under light microscope. Results DJ-1, Nrf2, HO-1 and caspase-3 were detected by western blot. DJ-1, Nrf2, HO-1 and caspase-3 in I/R group, D group and DI/R group was higher than that in S group. Compared with I/R group, Nrf2 and HO-1 in A group was decreased, but caspase-3 was increased. However, Nrf2 in DA group was higher than that in DI/R group, HO-1 and caspase-3 in DA group were lower than that in DI/R group. Compared with group S, Cr, Cys-C and β2-MG in I/R group, A group, D group, and DI/R group were higher. Whereas the levels of Cr, Cys-C, β2-MG and renal injury score in DA group were lower than those in DI/R group. Conclusion ATRA has a protective effect on renal ischemia-reperfusion injury in diabetic rats, maybe relating to DJ/Nrf2 pathway.

Vasculitis como presentación de leucemia promielocítica aguda / Vasculitis as a presentation of acute promyelocytic leukemia

Acute promyelocytic leukemiais a subtype of acute my eloid leukemia characterized by the presence of the PML:RAR aonco proteindueto a specific geneticalteration, translocation (15;17), which avoids my eloid differentiation, generating the accumulation of leukemic promyelocytes with posterior alteration of hemostasis. It presents with symptoms related to pancytopenia and thrombohemorrhagic coagulopathy, and there are few report sof cases with vasculitis secondary to promyelocytic leukemia. The clinical case aimed to describe a particular form of presentation of acute promyelocytic leukemia with vasculitis.

La leucemia promielocítica aguda es un subtipo de leucemia mieloide aguda caracterizada por la presencia de la oncoproteína PML-RARa debido a una alteracióngenéticaespecífica, la translocación (15;17), que impide la diferenciación mieloide generando la acumulación de promielocitos leucémicos y una alteración compleja de la hemostasia. Se presenta con síntomas relacionados a pancitopenia y coagulopatía trombo-hemorrágica existiendo escasos reportes de casos de vasculitis asociada a leucemia. El caso clínico descrito representa una forma particular de presentación de una leucemia promielocítica aguda con vasculitis.

Poroqueratosis de Mibelli en la edad pediátrica / Porokeratosis of Mibelli in pediatric age

Las poroqueratosis son un grupo heterogéneo de trastornos de la queratinización epidérmica, de presentación infrecuente. Se caracterizan clínicamente por pápulas hiperqueratósicas que confluyen y forman placas anulares con un centro atrófico y bordes sobreelevados. Hay seis variantes clínicas. El examen histopatológico evidencia la característica laminilla cornoide. Se presenta el caso de una niña de 2 años con diagnóstico de poroqueratosis de Mibelli y respuesta parcial al tratamiento tópico con tretinoína al 0,025%, que actualmente continúa en seguimiento clínico (AU)

Porokeratosis is a heterogeneous group of disorders in epidermal keratinization. It is an infrequent entity characterized clinically by hyperkeratotic papules that converge forming annular plaques with an atrophic center and raised borders. There are six clinical variants. The histopathological examination evidences the typical cornoid lamella. We present a 2-year-old girl diagnosed with porokeratosis of Mibelli and partial response to topical treatment of tretinoin 0,025%, still under clinical control (AU)

Effects of different culture systems on the culture of prepuberal buffalo (Bubalus bubalis) spermatogonial stem cell-like cells in vitro

Acrylamide reduces plasma antioxidant vitamin levels in rats due to increased oxidative damage / Acrilamida reduz os níveis de vitamina antioxidante no plasma em ratos devido ao aumento do dano oxidativo

ABSTRACT Objective Acrylamide is a potentially neurotoxic and carcinogenic chemical and naturally creates during the heating process of carbohydrate-rich foods, such as potato chips and breakfast cereals. Acrylamide might be ingested by people via consuming food that contains it. Therefore, we investigated the effect of acrylamidegiven orally to male and female rats on plasma retinoic acid and α-tocopherol and serum sialic acid and malondialdehyde levels. Method A total of 50 Wistar rats were used (25 female and 25 male, three-four weeks old). The rats of each sex were given 2 and 5mg/kg/day acrylamide via drinking water for 90 days. At the end of the treatment, the animals were euthanized by cervical dislocation. Blood specimens were collected through cardiac puncture, and serum and plasma samples were analysed using the high-performance liquid chromatography technique with a Ultraviolet detector. Results The analysis of the plasma and serum samples revealed that serum sialic acid and malondialdehyde levels in both sexes given 5mg/kg/day acrylamide were significantly increased, and the serum sialic acid levels were higher in female rats given 2mg/kg/day acrylamide. The plasma retinoic acid and α-tocopherol levels significantly decreased in both sexes given only the highest dose. Conclusion The results show that acrylamide causes an increase in oxidative stress and leads to a decrease in the levels of retinoic acid and α-tocopherol which play a role in the defense mechanism against this stress.

RESUMO Objetivo A acrilamida é um químico potencialmente neurotóxico e carcinogênico, sendo naturalmente criada durante o processo de aquecimento de alimentos ricos em carboidratos, como batatas fritas e cereais matinais. Dado que o composto pode ser ingerido através do consumo de alimentos, o presente trabalho teve por objetivo investigar o seu efeito, quando administrado oralmente a ratos, medindo-se os níveis plasmáticos de ácido retinoico e α-tocoferol, bem como os níveis séricos de ácido siálico e malondialdeído Métodos Foram utilizados cinquenta ratos Wistar, sendo metade de cada sexo, com idade entre três e quatro semanas. Os animais foram divididos em dois grupos, os quais receberam diferentes doses diárias de acrilamida, via água potável, durante noventa dias: o primeiro ingeriu 2mg/kg/dia; e o segundo, 5mg/kg/dia. Ao final do tratamento, os animais foram eutanasiados por meio de luxação cervical. Amostras de sangue foram coletadas através de punção cardíaca, assim como amostras de soro e plasma foram medidas usando-se a técnica de cromatografia líquida de alta performance com detector de Ultravioleta. Resultados A análise das amostras de plasma e soro revelou que os níveis de ácido siálico e malondialdeído, em ratos de ambos os sexos tratados com acrilamida de 5mg/kg/dia, foram significativamente aumentados, ao passo que os níveis séricos de ácido siálico foram maiores em ratas tratadas com 2mg/kg/dia de acrilamida. Já os níveis plasmáticos de ácido retinoico e α-tocoferol diminuíram significativamente em ratos de ambos os sexos, quando tratados com a dose mais elevada.Concl Conclusão Os resultados mostram que a acrilamida causa um aumento no estresse oxidativo e leva a uma diminuição nos níveis de ácido retinoico e α-tocoferol, que desempenham um papel no mecanismo de defesa contra esse estresse.

Retinoic acid increases the effect of bone morphogenetic protein type 2 on osteogenic differentiation of human adipose-derived stem cells

Abstract Bone morphogenetic protein type 2 (BMP-2) and retinoic acid (RA) are osteoinductive factors that stimulate endogenous mechanisms of bone repair which can be applied on management of osseous defects in oral and maxillofacial fields. Objective Considering the different results of RA on osteogenesis and its possible use to substitute/potency BMP-2 effects, this study evaluated the outcomes of BMP-2, RA, and BMP-2+RA treatments on in vitro osteogenic differentiation of human adipose-derived stem cells (ASCs) and the signaling pathway(s) involved. Material and Methods ASCs were treated every other day with basic osteogenic medium (OM) alone or supplemented with BMP-2, RA, or BMP-2+RA. Alkaline phosphatase (ALP) activity was determined using the r-nitrophenol method. Extracellular matrix mineralization was evaluated using von Kossa staining and calcium quantification. Expression of osteonectin and osteocalcin mRNA were determined using qPCR. Smad1, Smad4, phosphorylated Smad1/5/8, BMP-4, and BMP-7 proteins expressions were analyzed using western blotting. Signaling pathway was evaluated using the IPA® software. Results RA promoted the highest ALP activity at days 7, 14, 21, and 28, in comparison to BMP-2 and BMP-2+RA. BMP-2+RA best stimulated phosphorylated Smad1/5/8 protein expression at day 7 and Smad4 expression at days 7, 14, 21, and 28. Osteocalcin and osteonectin mRNA expressions were best stimulated by BMP-2+RA at day 7. Matrix mineralization was most improved by BMP-2+RA at days 12 and 32. Additionally, BMP-2+RA promoted the highest BMP signaling pathway activation at days 7 and 14, and demonstrated more activation of differentiation of bone-forming cells than OM alone. Conclusions In summary, RA increased the effect of BMP-2 on osteogenic differentiation of human ASCs.

Research Advances on Mechanisms of Resistance to All-Trans Retinoic Acid in Acute Promyelocytic Leukemia--Review / 中国实验血液学杂志

Abstract　　Among myeloid leukemias, the acute promyelocytic leukemia (APL) was found to be specifically sensitive to all-trans retinoic acid (ATRA), almost all APL patients respond to ATRA therapy. The ATRA induces remission of APL patients by stimulating the differentiation of the leukemia cells. However, with the long-term application of ATRA alone, ATRA resistance has become one of the main causes of chemotherapy failure in the patients with acute promyelocytic leukemia. At present, the mechanism of ATRA-resistance is not completely clear, this review discusses the mechanism of drug-resistance in terms of signal pathways, genes, proteins and enzyme.

Ursolic Acid Prevents Retinoic Acid-Induced Bone Loss in Rats / 中国结合医学杂志

OBJECTIVE@#To examine the effects of ursolic acid (UA) on mitigating retinoic acid (RA)-induced osteoporosis in rats.@*METHODS@#Fifty female Sprague-Dawley rats were randomly divided into the control group (n=10) and the osteoporosis group (n=40). The 40 osteoporosis rats were induced by 75 mg/(kg•d) RA once daily for 2 weeks, and then were randomly assigned to vehicle control (model), low-, middle-, and high-dose UA [(UA-L, UA-M, UA-H; 30, 60, 120 mg/(kg•d), respectively] groups (10 rats each). UA were administered once daily to the rats from the 3rd weeks for up to 4 weeks by gavage. Bone turnover markers [serum alkaline phosphatase (ALP), osteocalcin (OCN), urine deoxypyridinoline (DPD)] and other parameters, including serum calcium (S-Ca), serum phosphorus (S-P), urine calcium (U-Ca), urine phosphorus (U-P), and bone mineral density (BMD) of the femur, 4th lumbar vertebra and tibia, bone biomechanical properties and trabecular microarchitecture, were measured.@*RESULTS@#The osteoporosis in rats was successfully induced by RA. Compared with the model group, UA-M and UA-H significantly reversed the RA-induced changes in S-P, U-Ca, U-P, ALP, OCN and urine DPD ratio and markedly enhanced the BMD of right femur, 4th lumbar vertebra and tibia (Plt;0.05 or Plt;0.01). Further, biomechanical test and microcomputed tomography evaluation also showed that UA-H drastically improved biomechanical properties and trabecular microarchitecture (Plt;0.05 or Plt;0.01).@*CONCLUSION@#UA could promote bone formation, increase osteoblastic activity and reduce osteoclastic activity in rats, indicating that UA might be a potential therapeutic of RA-induced acute osteoporosis.

Efficacy and Safety of the Induction Therapy with Different Doses of Anthracyclines for Patients with Newly Diagnosed Acute Promyelocytic Leukemia / 中国实验血液学杂志

@#]Objective:To investigate the efficacy and safety of induction regimens containing arsenite, allo-transretinoic acid (ATRA) and anthracyclines of different doses as induction chemotherapy for acute promyelocytic leukemia (APL).@*METHODS@#The clinical data of 129 consecutive hospitalized newly diagnosed APL patients from January 2011 to December 2017 were collected and retrospectively analyzed. Sixty-six patients received arsenite, ATRA and anthracyclines of low doses (low dose group), while other 63 patients received arsenite, ATRA and anthracyclines of standard doses (standard dose group), the efficacy and safety were compared and analyzed in 2 groups.@*RESULTS@#There were no statistically significant differences in terms of age, sex, routine blood indexes,LDH level, bone marrow promyelocyte count,prognostic stratification between patients in two groups (P>0.05). During the treatment, WBC count peak and its time point were not significantly different between two groups (P>0.05). Both induction regimens showed good efficacy, the PML-RARα gene conversion rate from positive into negative, the 2-year overall survival rate and disease-free survival rate in the low-dose group were similar to those in the standard dose group(P＞0.05). The recovery time of neutrophils and platelets in the low-dose group was 0 d and 11 d, respectively, which were statistically  significantly shorter than those in the standard dose group (3 d,15 d) (both P=0.000). The median value of platelet and erythrocyte transfusion in the low-dose group was 6.9 U and 4.2 U, respectively, which were statistically significantly lower than that in the standard dose group (8.4 U,6.8 U) (P=0.037，0.000). And the inpatient time in the low and the standard dose groups were 30.98 and 30.71 days, respectively (P=0.770).@*CONCLUSION@#For newly diagnosed patients with APL, the efficacy was similar between induction therapy containing arsenite,ATRA and low dose anthracyclines and the induction therapy containing arsenite, ATRA and standard dose anthracyclines, however, the former appears even safer.

Adenanthin Induces Differentiation of Acute Promyelocytic Leukemia Cells by Targeting Peroxiredoxin III / 中国实验血液学杂志

OBJECTIVE@#To investigate the differentiation of acute promyelocytic leukemia (APL) cells induced by adenosine targeting Prx III.@*METHODS@#HL-60 cells were divided into four groups: control group, all-trans retinoic acid (ATRA) group, adenanthin group and ATRA+adenanthin group. Cell morphologic changes were observed under optical microscope. The influence of adenanthin on the differentiation of HL-60 was observed by nitro blue tetrazolium chloride (NBT) test. Cell surface differentiation antigens CD11b expression was measured by flow cytometry. The protein expression of Prx III was detected by immunohistochemical assay.@*RESULTS@#Adenanthin could induce the differentiation of HL-60 cells; the NBT reduction positive rate in ATRA+adenanthin group was significantly higher than that in ATRA group and adenanthin group (P＜0.05). The percentage of CD11b positive cells in ATRA+adenanthin group (43.62％±1.38％) was higher than that in adenanthin group (28.15％±1.78％), ATRA group (36.72％±1.33％) and control group (7.99％±1.78％) (P＜0. 05). The content of Prx Ⅲ protein in adenanthin group was significantly higher than that in control group and ATRA group (P＜0.05).@*CONCLUSION@#Adenanthin and ATRA have a synergistic effect on the differentiation and maturation of HL-60 cells, and its mechanism may be related with regulation of Prx III expression.

Effect of Chromosomal Karyotype on the Prognosis of Patients with Acute Promyelocytic Leukemia in Condition of the Maintenance Treatment Based on Arsenic Trioxide / 中国实验血液学杂志

OBJECTIVE@#To investigate the effect of chromosomal karyotype on the prognosis of patients with acute promyelocytic leukemia (APL) in condition of the maintenance treatment based on arsenic trioxide.@*METHODS@#The patients with acute promyelocytic leukemia for last 12 years in our hospital were retrospectively collected. The patients mainly treated with arsenic trioxide in maintenance protocol were selected and followed up. All the patients were divided into 3 groups according to cytogenetic data: single t (15; 17) group, t (15; 17) with additional chromosomal abnormality (ACA) group, and normal karyotype group. Then, the prognostic significance of ACAs and complex karyotype were investigated in APL patients.@*RESULTS@#There were 57 cases in the single t (15; 17) group, in which 8 cases died in the first month after induction treatment with early mortality rate of 14%. There were 21 patients in t (15; 17) with ACA group, in which 4 cases died in the first month with early mortality rate of 19%. There were 15 cases in normal chromosome group, in which 5 cases died in the first month with the early mortality rate of 33.3%. There was no statistical difference in the early mortality among 3 groups. All the remaining 76 patients achieved complete hematological remission. These patients were followed up. The median follow-up time was 43.9 months. Among them, only 2 patients in single t (15; 17) group and 1 patient in t (15; 17) with ACA group relapsed. No patient relapsed in normal karyotype group. The relapse rate was 3.5% in single t (15; 17) group and 4.2% in t (15; 17) with ACA group, respectively. There was no statistical difference in the overall survival and disease-free survival rates among 3 groups. Further analysis showed that the patients with complex chromosome karyotypes had lower relapse-free survival rates, but overall survival rates were not significantly different in 3 group.@*CONCLUSION@#In general, ACA can not affect the prognosis of patients with acute promyelocytic leukemia in condition of the maintenance treatment based on arsenic trioxide, but the complex chromosomal karyotype may reduce the relapse-free survival rates.