Ferritin heavy/light chain (FTH1/FTL) expression, serum ferritin levels, and their functional as well as prognostic roles in acute myeloid leukemia

Iron and Cancer: 2020 Vision

New and provocative insights into the relationships between iron and cancer have been uncovered in recent years. These include delineation of connections that link cellular iron to DNA repair, genomic integrity, and oncogenic signaling as well as the discovery of ferroptosis, a novel iron-dependent form of cell death. In parallel, new molecules and pathways that regulate iron influx, intracellular iron trafficking, and egress in normal cells, and their perturbations in cancer have been discovered. In addition, insights into the unique properties of iron handling in tumor-initiating cells (cancer stem cells), novel contributions of the tumor microenvironment to the uptake and regulation of iron in cancer cells, and new therapeutic modalities that leverage the iron dependence of cancer have emerged.

Knockdown of ferritin heavy chain (FTH) inhibits the migration of prostate cancer through reducing S100A4, S100A2, and S100P expression

BACKGROUND

Ferritin plays a key role in the development of prostate cancer (PCa). Our earlier studies showed that the knockdown of ferritin heavy chain (FTH) suppressed the migration and invasion of the prostate cancer cell line (PC3). However, the mechanisms behind FTH in the cell migration regulation of PCa have not been thoroughly investigated.

METHODS

Isobaric tags for relative and absolute quantitation (iTRAQ) proteomics was used to analyze the protein expression in PC3 cells with FTH knockdown by small interfering RNAs and negative control cells. We subsequently ranked the differentially expressed proteins according to the change in expression. We further performed Gene Ontology (GO) analysis for the changing-expression protein. Finally, Western blot analysis was performed to determine the expression of the target protein.

RESULTS

Compared with the negative group, 420 proteins were downregulated, including proteins S100A4, S100P, and S100A2, while the expression of 442 protein was elevated in FTH-silencing PC3 cells (P<0.05, fold change >1.2). The mass spectrometry results showing decreased expression of protein S100A4, S100P, and S100A2 in the cells were further validated by Western blot (P<0.05). Levels of protein S100A4, S100A2, and S100P were reduced in FTH-silencing PC3 cells (P<0.05, fold change >1.6).

CONCLUSIONS

The downregulation of FTH expression reduced the level of protein S100A4, S100A2, and S100P, which all play a key role in the migration and invasion of tumor cells. Therefore, it is reasonable to assume that there are correlations between the expression of the S100A4, S100A2, and S100P genes with FTH. Based on this research, FTH may be a new biomarker for the diagnosis of PCa.

Screening of immune-related differentially expressed genes from primary lymphatic organs of broilers fed with probiotic bacillus cereus PAS38 based on suppression subtractive hybridization

To explore the molecular mechanism of the effect of Bacillus cereus PAS38 on the immunity of broilers, sixty 7-day-old broilers were divided into two groups with three replicates. The control group was fed with basal diet, and the treatment group was fed with basal diet containing Bacillus cereus PAS38 1×10⁶ CFU/g. Thymus and bursa of fabricius were taken from two groups of broilers at the age of 42 days, total RNA was extracted, differential gene library was constructed by SSH technology, and immune-related differential genes were screened. Then, we used siRNA to interfere with the expression of some differential genes in the original generation lymphocytes of broiler blood to detect the change of cytokines mRNA expression level. A total of 42 immune-related differentially expressed genes were screened, including 22 up-regulated genes and 20 down-regulated genes. When 7 differentially up-regulated genes associated with enhanced immune function were interfered with in lymphocytes, some immune-promoting cytokines were down-regulated. These results showed that Bacillus cereus PAS38 might up-regulate the expression of JCHAIN, PRDX1, CD3E, CDK6 and other genes in immune organs of broilers, thereby affecting the development of immune organs, the expression of various cytokines and the transduction of immune signals, improving the immune capacity of broilers.

CD34+CD38-CD123+ Leukemic Stem Cell Frequency Predicts Outcome in Older Acute Myeloid Leukemia Patients Treated by Intensive Chemotherapy but Not Hypomethylating Agents

The prognostic impact of immunophenotypic CD34⁺CD38⁻CD123⁺ leukemic stem cell (iLSC) frequency at diagnosis has been demonstrated in younger patients treated by intensive chemotherapy, however, this is less clear in older patients. Furthermore, the impact of iLSC in patients treated by hypomethylating agents is unknown. In this single-center study, we prospectively assessed the CD34⁺CD38⁻CD123⁺ iLSC frequency at diagnosis in acute myeloid leukemia (AML) patients aged 60 years or older. In a cohort of 444 patients, the median percentage of iLSC at diagnosis was 4.3%. Significant differences were found between treatment groups with a lower median in the intensive chemotherapy group (0.6%) compared to hypomethylating agents (8.0%) or supportive care (11.1%) (p <0.0001). In the intensive chemotherapy group, the median overall survival was 34.5 months in patients with iLSC ≤0.10% and 14.6 months in patients with >0.10% (p = 0.031). In the multivariate analyses of this group, iLSC frequency was significantly and independently associated with the incidence of relapse, event-free, relapse-free, and overall survival. However, iLSC frequency had no prognostic impact on patients treated by hypomethylating agents. Thus, the iLSC frequency at diagnosis is an independent prognostic factor in older acute myeloid patients treated by intensive chemotherapy but not hypomethylating agents.

FtH-Mediated ROS Dysregulation Promotes CXCL12/CXCR4 Axis Activation and EMT-Like Trans-Differentiation in Erythroleukemia K562 Cells

The cell-microenvironment communication is essential for homing of hematopoietic stem cells in stromal niches. Recent evidences support the involvement of epithelial-to-mesenchymal (EMT) process in hematopoietic stem cell homeostasis as well as in leukemia cells invasiveness and migration capability. Here, we demonstrate that the alteration of iron homeostasis and the consequent increase of redox metabolism, mediated by the stable knock down of ferritin heavy chain (FtH), enhances the expression of CXCR4 in K562 erythroleukemia cells, thus promoting CXCL12-mediated motility. Indeed, addition of the CXCR4 receptor antagonist AMD3100 reverts this effect. Upon FtH knock down K562 cells also acquire an “EMT-like” phenotype, characterized by the increase of Snail, Slug and Vimentin with the parallel loss of E-cadherin. By using fibronectin as substrate, the cell adhesion assay further shows a reduction of cell adhesion capability in FtH-silenced K562 cells. Accordingly, confocal microscopy shows that adherent K562 control cells display a variety of protrusions while FtH-silenced K562 cells remain roundish. These phenomena are largely due to the reactive oxygen species (ROS)-mediated up-regulation of HIF-1α/CXCR4 axis which, in turn, promotes the activation of NF-κB and the enhancement of EMT features. These data are confirmed by treatments with either N-acetylcysteine (NAC) or AMD3100 or NF-κB inhibitor IκB-alpha which revert the FtH-silenced K562 invasive phenotype. Overall, our findings demonstrate the existence of a direct relationship among iron metabolism, redox homeostasis and EMT in the hematological malignancies. The effects of FtH dysregulation on CXCR4/CXCL12-mediated K562 cell motility extend the meaning of iron homeostasis in the leukemia cell microenvironment.

Iron: The cancer connection

Iron plays an essential role in normal biological processes: The generation of cellular energy, oxygen transport, DNA synthesis and repair are all processes that require iron-coordinated proteins, either as elemental iron, heme or iron-sulfur clusters. As a transition metal with two major biological oxidation states, iron is also a critical intermediate in the generation of reactive oxygen species that can damage cellular structures and contribute to both aging and cancer. In this review, we focus on experimental and epidemiologic evidence that links iron and cancer, as well as strategies that have been proposed to either reduce or increase cellular iron for cancer therapy.

Screening of differentially expressed immune-related genes from spleen of broilers fed with probiotic Bacillus cereus PAS38 based on suppression subtractive hybridization

The aim of this study was to construct the spleen differential genes library of broilers fed with probiotic Bacillus cereus PAS38 by suppression subtractive hybridization (SSH) and screen the immune-related genes. Sixty seven-day-old broilers were randomly divided into two groups. The control group was fed with basal diet, and the treated group was fed with basal diet containing Bacillus cereus PAS38 1×10⁶ CFU/g. Spleen tissues were taken and extracted its total RNA at 42 days old, then SSH was used to construct differential gene library and screen immune-related genes. A total of 119 differentially expressed sequence tags (ESTs) were isolated by SSH and 9 immune-related genes were screened out by Gene ontology analysis. Nine differentially expressed genes were identified by qRT-PCR. JCHAIN, FTH1, P2RX7, TLR7, IGF1R, SMAD7, and SLC7A6 were found to be significantly up-regulated in the treated group. Which was consistent with the results of SSH. These findings imply that probiotic Bacillus cereus PAS38-induced differentially expressed genes in spleen might play an important role in the improvement of immunity for broilers, which provided useful information for further understanding of the molecular mechanism of probiotics responsible to affect the poultry immunity.

Iron and leukemia: new insights for future treatments

Iron, an indispensable element for life, is involved in all kinds of important physiological activities. Iron promotes cell growth and proliferation, but it also causes oxidative stress damage. The body has a strict regulation mechanism of iron metabolism due to its potential toxicity. As a cancer of the bone marrow and blood cells, leukemia threatens human health seriously. Current studies suggest that dysregulation of iron metabolism and subsequent accumulation of excess iron are closely associated with the occurrence and progress of leukemia. Specifically, excess iron promotes the development of leukemia due to the pro-oxidative nature of iron and its damaging effects on DNA. On the other hand, leukemia cells acquire large amounts of iron to maintain rapid growth and proliferation. Therefore, targeting iron metabolism may provide new insights for approaches to the treatment of leukemia. This review summarizes physiologic iron metabolism, alternations of iron metabolism in leukemia and therapeutic opportunities of targeting the altered iron metabolism in leukemia, with a focus on acute leukemia.

Value of Ferritin Heavy Chain (FTH1) Expression in Diagnosis and Prognosis of Renal Cell Carcinoma

BACKGROUND Serum ferritin is a useful tumor marker for renal cell carcinoma (RCC). However, the expression of ferritin heavy chain (FTH1), the main subunit of ferritin, is unclear in primary RCC tissues. In this study, we investigated FTH1 mRNA expression and its diagnostic and prognostic value in RCC. MATERIAL AND METHODS The mRNA expression of FTH1 was analyzed using including Oncomine, Gene Expression Omnibus, and Cancer Genome Atlas datasets, while the protein level of FTH1 was analyzed using the Human Protein Atlas database. The associations between FTH1 and clinicopathologic characteristics and survival time and Cox multivariate survival analysis were analyzed using SPSS 22.0 software. A meta-analysis was performed to assess consistency of FTH1 expression. GO, KEGG, and PPI analyses were used to predict biological functions. RESULTS According to TCGA data, overexpression of FTH1 was detected in 890 RCC tissues (15.2904±0.63157) compared to 129 normal kidney tissues (14.4502±0.51523, p<0.001). Among the clinicopathological characteristics evaluated, patients with increased pathologic T staging, lymph node metastasis, and distant metastasis were significantly associated with higher expression of FTH1. Elevated FTH1 mRNA levels were correlated with worse prognosis of RCC patients. Cox multivariate survival analysis indicated that age, stage, and M stage were predictors of poor prognosis in patients with RCC. CONCLUSIONS Our data suggest that FTH1 expression is an effective prognostic and diagnosis biomarker for RCC.