RESUMEN

Acute myeloid leukemia (AML) is a type of hematological malignancy caused by uncontrolled clonal proliferation of hematopoietic stem cells. The special energy metabolism mode of AML relying on oxidative phosphorylation is different from the traditional 'Warburg effect'. However, its mechanism is not clear. In the present study, it was demonstrated that the mRNA expression levels of NADH dehydrogenase subunit 1, 4 and 5 (ND1, ND4 and ND5) were upregulated in AML samples from The Cancer Genome Atlas database using the limma package in the R programming language. Reverse transcription­quantitative PCR and ELISA were used to verify the upregulation of ND1, ND4 and ND5 in clinical samples. Pan­cancer analysis revealed that the expression of ND1 was upregulated only in AML, ND2 was upregulated only in AML and thymoma, and ND4 was upregulated only in AML and kidney chromophobe. In the present study, it was demonstrated that silencing of ND1/4/5 could inhibit the proliferation of AML cells in transplanted tumor of nude mice. Additionally, it was found that oxidative phosphorylation and energy metabolism of AML cells were decreased after silencing of ND1/4/5. In conclusion, the present study suggested that ND1/4/5 may be involved in the regulation of oxidative phosphorylation metabolism in AML as a potential cancer­promoting factor.

Asunto(s)

RESUMEN

Acute myeloid leukemia (AML) is a malignant disease originating from myeloid hematopoietic stem or progenitor cells. It is important to identify molecules associated with the prognosis of AML and conduct an individual risk assessment for different patients. In the present study, the RNA expression profile of 132 patients with AML and 337 healthy individuals were downloaded from the University of California Santa Cruz Xena and the Genotype-Tissue Expression project databases. Differentially expressed mRNA (DEmRNA) transcripts between normal blood and AML blood were identified. Among these, prognosis-associated signature mRNA molecules were screened using univariate Cox and least absolute shrinkage and selection operator regression. A total of four genes, namely, family with sequence similarity 124 member B (FAM124B), 4-hydroxyphenylpyruvate dioxygenase-like protein (HPDL), myeloperoxidase (MPO) and purinergic receptor P2Y1 (P2RY1), were identified using multivariate Cox regression analysis and were used to construct a prognostic scoring system. Moreover, the expression levels of HPDL and MPO were higher in the samples with high immunity scores and estimate scores (sum of stromal score and immune score), compared with those with low scores. Reverse transcription-quantitative PCR and western blot analysis were used to confirm the upregulation of the four candidate genes in AML cell lines as well as in clinical AML samples. In summary, the present study identified a novel mRNA-based prognostic risk scoring system for patients with AML. The four genes used in this scoring system may also play an important role in AML.

RESUMEN

The aim of the present study was to analyze the sequence of the VP1 gene in enterovirus 71 (EV71) isolates and to explore their genetic evolution, so as to provide a scientific basis for the clinical prevention and treatment of hand, foot and mouth disease. The fecal samples of 590 patients with suspected hand, foot and mouth disease treated at Yan'an Hospital (Kunming, China) between January 2015 and December 2016 were collected and EV71 nucleic acid was detected by fluorescence PCR. The viral RNA of EV71-positive samples was extracted, the VP1 gene was amplified by PCR and the products were sequenced. The VP1 gene sequence was analyzed using DNAMAN and MEGA (version 4.0) software and homologous modeling was performed using Pymol software. A total of 50 EV71-positive samples were identified and the detection rate was 8.47% (50/590 cases). All of the 50 EV71 strains were of the C4 subtype. The genetic distance between the strains detected in the present study and EV71 strains detected in Beijing, Anhui and Malaysia was 0.01-0.03, while that between the strains detected in the present study and Australian strains was 2.11. Homologous modeling indicated that the amino acid sequence of the VP1 gene of the detected strains had a H144Y mutation. There was no significant genetic variation in the EV71 strain within the 2-year period. In conclusion, the EV71 strains detected in the present study was similar to that detected in Beijing, Anhui and Malaysia but different to that from Australia. A point mutation was present in the amino acid sequence of the VP1 gene.

RESUMEN

Apoptin, a small protein derived from chicken anemia virus, possesses the capacity to specifically kill tumor cells while leaving normal cells intact. Previous studies have indicated that the subcellular localization of apoptin appears to be crucial for this tumor-selective activity. Apoptin resides in the cytoplasm of normal cells; however, in cancer cells it translocates into the nucleus. In the present study, purified prokaryotic native His-apoptin served as a bait for capturing apoptin-associated proteins in both a hepatoma carcinoma cell line (HepG2) and a human fetal liver cell line (L-02). The captured proteins obtained from a pull-down assay were separated by two-dimensional gel electrophoresis. Mass spectrometry was employed to detect the effect of HSPA9 overexpression (one of the interacting proteins with apoptin in vitro) and downregulation of HSPA9 on HepG2 cells. The data revealed that HSPA9 overexpression resulted in partial distribution of apoptin in the cytoplasm. Notably, HSPA9 overexpression markedly decreased the apoptosis rate of HepG2 cells from 41.2 to 31.7%, while the downregulation of HSPA9 using small interfering RNA significantly enhanced the apoptosis of HepG2 cells. Our results suggest new insights into the localization mechanism of apoptin which is tightly associated with HSPA9 overexpression and its crucial role in cellular apoptosis both in a tumor cell line (HepG2) and a normal cell line (L-02). These findings shed new light on the elucidation of the underlying mechanism of anticancer action of apoptin.

Asunto(s)

RESUMEN

This study examined the effect of insulin on the expression of very low density lipoprotein receptor (VLDLR) subtypes of SGC7901 cells and discussed its biological implication. In vitro, moderately or poorly-differentiated human gastric adenocarcinoma cell line SGC7901 was incubated with insulin for different lengths of time, and then the expression of protein and RNA level in VLDLR subtypes were detected by Western blotting and real-time PCR, respectively. The results showed that, at certain time interval, insulin could down-regulate expression of type I VLDLR and up-regulate the expression of type II VLDLR in SGC7901 cells, at both protein and RNA level. We are led to conclude that insulin serves as a regulator in maintaining the balance between glucose and lipid metabolism in vivo, possibly through its effect on the differential expression of VLDLR subtypes.

Asunto(s)

RESUMEN

This study examined the effect of insulin on the expression of very low density lipoprotein receptor (VLDLR) subtypes of SGC7901 cells and discussed its biological implication. In vitro,moderately or poorly-differentiated human gastric adenocarcinoma cell line SGC7901 was incubated with insulin for different lengths of time, and then the expression of protein and RNA level in VLDLR subtypes were detected by Western blotting and real-time PCR, respectively. The results showed that, at certain time interval, insulin could down-regulate expression of type Ⅰ VLDLR and up-regulate the expression of type Ⅱ VLDLR in SGC7901 cells, at both protein and RNA level.We are led to conclude that insulin serves as a regulator in maintaining the balance between glucose and lipid metabolism in vivo, possibly through its effect on the differential expression of VLDLR subtypes.