Enhanced expressions of FHL2 and iASPP predict poor prognosis in acute myeloid leukemia

Oxidative stress is two-sided in the treatment of acute myeloid leukemia

INTRODUCTION

Oxidative stress caused by elevated ROS, as a novel therapeutic mechanism, has been implicated in various tumors including AML. AML cells are chronically under oxidative stress, yet overreliance on ROS production makes tumor cells increasingly vulnerable to further damage. Reducing the cytotoxic effect of ROS on normal cells while killing leukemia stem cell (LSC) with high levels of reactive oxygen species is a new challenge for oxidative stress therapy in leukemia.

METHODS

By searching literature databases, we summarized recent relevant studies. The relationship of ROS on AML genes, signaling pathways, and transcription factors, and the correlation of ROS with AML bone marrow microenvironment and autophagy were summarized. In addition, we summarize the current status of research on ROS and AML therapeutics. Finally, we discuss the research progress on redox resistance in AML.

RESULTS

This review discusses the evidence showing the link between redox reactions and the progression of AML and compiles the latest research findings that will facilitate future biological studies of redox effects associated with AML treatment.

CONCLUSION

We believe that exploiting this unique oxidative stress property of AML cells may provide a new way to prevent relapse and drug resistance.

iASPP suppression mediates terminal UPR and improves BRAF-inhibitor sensitivity of colon cancers

Unfolded protein response (UPR) signaling is activated under endoplasmic reticulum (ER) stress, an emerging cancer hallmark, leading to either adaptive survival or cell death, while the mechanisms underlying adaptation-death switch remain poorly understood. Here, we examined whether oncogene iASPP regulates the switch and how the mechanisms can be used in colon cancer treatment. iASPP is downregulated when cells undergo transition from adaptation to death during therapy-induced ER stress. Blocking iASPP's downregulation attenuates stress-induced cell death. Mechanistically, Hu-antigen R (HuR)-mediated stabilization of iASPP mRNA and subsequent iASPP protein production is significantly impaired with prolonged ER stress, which facilitates the degradation of GRP78, a key regulator of the UPR, in the cytosol. Because iASPP competes with GRP78 in binding the ER-resident E3 ligase RNF185, and tips the balance in favor of cell death. Positive correlation between the levels of HuR, iASPP, and GRP78 are detectable in colon cancer tissues in vivo. Genetic inhibition of iASPP/GRP78 or chemical inhibition of HuR not only inhibits tumor growth, but also sensitizes colon cancer cells' responses to BRAF inhibitor-induced ER stress and cell death. This study provides mechanistic insights into the switch between adaptation and death during ER stress, and also identifies a potential strategy to improve BRAF-inhibitor efficiency in colon cancers.

High level of FHL2 exacerbates the outcome of non-small cell lung cancer (NSCLC) patients and the malignant phenotype in NSCLC cells

Non-small cell lung cancer (NSCLC) is a malignant tumour with high mortality. FHL2 has been identified as a biomarker of lung cancer. This research explored the effects of FHL2 expression on NSCLC. NSCLC-associated data sets were collected from the assistant for clinical bioinformatics and TCGA databases respectively. The association between FHL2 and clinical characteristics, the prognostic significance of FHL2 and the influences of various variables on NSCLC were determined by Pearson's chi-squared test, the Kaplan-Meier curve and the Cox regression model respectively. FHL2 level was altered by cell transfection and was measured by qRT-PCR. Tumour xenograft formation was completed by inoculating sh-FHL2/pcDNA-FHL2 transfected cells into BALB/c nude mice. Protein expression was assessed by western blot. Cell apoptosis, proliferation and epithelial - mesenchymal transition (EMT) characteristics were evaluated employing TUNEL, BrdU⁺ and microscopic observation respectively. The expression of Ki67 and N-cadherin was assessed by immunohistochemistry. The results showed that FHL2 was highly expressed in NSCLC tissues. Patients with high FHL2 expression experienced lower overall survival probability. FHL2 knockdown promoted apoptosis, but inhibited EMT of A549 and NCI-H460 cells, which was verified by the increased ratios of cleaved caspase 9/caspase 9 and cleaved caspase 3/caspase 3, as well as augmented E-cadherin and reduced N-cadherin. In an in vivo assay FHL2 knockdown decreased tumour volume and weight, repressed EMT, but enhanced apoptosis. FHL2 upregulation showed the opposite effects of FHL2 knockdown. Furthermore, FHL2 upregulation facilitated cell proliferation both in in vitro and in vivo assays. These outcomes indicated that high level of FHL2 facilitated tumorigenesis, as well as the proliferation and EMT of NSCLC cells.

How (Epi)Genetic Regulation of the LIM-Domain Protein FHL2 Impacts Multifactorial Disease

Susceptibility to complex pathological conditions such as obesity, type 2 diabetes and cardiovascular disease is highly variable among individuals and arises from specific changes in gene expression in combination with external factors. The regulation of gene expression is determined by genetic variation (SNPs) and epigenetic marks that are influenced by environmental factors. Aging is a major risk factor for many multifactorial diseases and is increasingly associated with changes in DNA methylation, leading to differences in gene expression. Four and a half LIM domains 2 (FHL2) is a key regulator of intracellular signal transduction pathways and the FHL2 gene is consistently found as one of the top hyper-methylated genes upon aging. Remarkably, FHL2 expression increases with methylation. This was demonstrated in relevant metabolic tissues: white adipose tissue, pancreatic β-cells, and skeletal muscle. In this review, we provide an overview of the current knowledge on regulation of FHL2 by genetic variation and epigenetic DNA modification, and the potential consequences for age-related complex multifactorial diseases.

Prognostic Value of MicroRNA-20b in Acute Myeloid Leukemia

Acute myeloid leukemia (AML) is a highly heterogeneous disease that requires fine-grained risk stratification for the best prognosis of patients. As a class of small non-coding RNAs with important biological functions, microRNAs play a crucial role in the pathogenesis of AML. To assess the prognostic impact of miR-20b on AML in the presence of other clinical and molecular factors, we screened 90 AML patients receiving chemotherapy only and 74 also undergoing allogeneic hematopoietic stem cell transplantation (allo-HSCT) from the Cancer Genome Atlas (TCGA) database. In the chemotherapy-only group, high miR-20b expression subgroup had shorter event-free survival (EFS) and overall survival (OS, both P < 0.001); whereas, there were no significant differences in EFS and OS between high and low expression subgroups in the allo-HSCT group. Then we divided all patients into high and low expression groups based on median miR-20b expression level. In the high expression group, patients treated with allo-HSCT had longer EFS and OS than those with chemotherapy alone (both P < 0.01); however, there were no significant differences in EFS and OS between different treatment subgroups in the low expression group. Further analysis showed that miR-20b was negatively correlated with genes in “ribosome,” “myeloid leukocyte mediated immunity,” and “DNA replication” signaling pathways. ORAI2, the gene with the strongest correlation with miR-20b, also had significant prognostic value in patients undergoing chemotherapy but not in the allo-HSCT group. In conclusion, our findings suggest that high miR-20b expression is a poor prognostic indicator for AML, but allo-HSCT may override its prognostic impact.

Prognostic value of HMGN family expression in acute myeloid leukemia

Aim: The objective of this work was to investigate the prognostic role of the HMGN family in acute myeloid leukemia (AML). Methods: A total of 155 AML patients with HMGN1-5 expression data from the Cancer Genome Atlas database were enrolled in this study. Results: In the chemotherapy-only group, patients with high HMGN2 expression had significantly longer event-free survival (EFS) and overall survival (OS) than those with low expression (all p < 0.05), whereas high HMGN5 expressers had shorter EFS and OS than the low expressers (all p < 0.05). Multivariate analysis identified that high HMGN2 expression was an independent favorable prognostic factor for patients who only received chemotherapy (all p < 0.05). HMGN family expression had no impact on EFS and OS in AML patients receiving allogeneic hematopoietic stem cell transplantation. Conclusion: High HMGN2/5 expression is a potential prognostic indicator for AML.

LncRNA DLX6-AS1 aggravates the development of ovarian cancer via modulating FHL2 by sponging miR-195-5p

Background

Ovarian cancer (OC) is a huge burden on women’s lives. Recently, the implication of long non-coding RNAs (lncRNAs) in cancers, including OC, has aroused much attention. The objective of this study was to explore the role and functional mechanism of lncRNA distal-less homeobox 6 antisense 1 (DLX6-AS1) in OC.

Methods

The expression of DLX6-AS1, miR-195-5p, and four and a half LIM domains protein 2 (FHL2) was measured by quantitative real-time polymerase chain reaction (qRT-PCR). The cell proliferation, apoptosis, migration, and invasion were assessed by cell count kit 8 (CCK-8), flow cytometry and transwell assays, respectively. The protein levels of proliferating cell nuclear antigen (PCNA), cleaved-caspase-3 (C-caspase 3), N-cadherin, Vimentin, E-cadherin and FHL2 were quantified by western blot. The relationship between miR-195-5p and DLX6-AS1 or FHL2 was predicted by bioinformatics tool starBase and verified by luciferase reporter assay and RNA immunoprecipitation (RIP) assay. Xenograft tumor model was established to observe the role of DLX6-AS1 in vivo.

Results

DLX6-AS1 and FHL2 were up-regulated in OC tissues and cells, while miR-195-5p was down-regulated. DLX6-AS1 knockdown inhibited proliferation, migration, and invasion but induced apoptosis of OC cells. However, miR-195-5p inhibition reversed these effects. Overexpression of miR-195-5p also depleted proliferation, migration, and invasion but promoted apoptosis of OC cells, while FHL2 overexpression overturned these influences. DLX6-AS1 knockdown blocked tumor growth in vivo.

Conclusion

DLX6-AS1, as an oncogene in OC, accelerated tumor progression by up-regulating FHL2 via mediating miR-195-5p, suggesting that DLX6-AS1 was a hopeful target for the lncRNA-targeted therapy in OC.

Upregulation of Glutamic-Oxaloacetic Transaminase 1 Predicts Poor Prognosis in Acute Myeloid Leukemia

One of the key features of acute myeloid leukemia (AML), a group of very aggressive myeloid malignancies, is their strikingly heterogenous outcomes. Accurate biomarkers are needed to improve prognostic assessment. Glutamate oxaloacetate transaminase 1 (GOT1) is essential for cell proliferation and apoptosis by regulating cell's metabolic dependency on glucose. It is unclear whether the expression level of GOT1 has clinical implications in AML. Therefore, we analyzed the data of 155 AML patients with GOT1 expression information from The Cancer Genome Atlas (TCGA) database. Among them, 84 patients were treated with chemotherapy alone, while 71 received allogeneic hematopoietic stem cell transplantation (allo-HSCT). In both treatment groups, high GOT1 expression was associated with shorter event-free survival (EFS) and overall survival (OS) (all P < 0.05). Multivariate analysis identified several independent risk factors for both EFS and OS in the chemotherapy-only group, including high GOT1 expression, age ≥60 years, white blood cell count ≥15 × 10⁹/L, bone marrow blasts ≥70%, and DNMT3A, RUNX1 or TP53 mutations (all P < 0.05); but in the allo-HSCT group, the only independent risk factor for survival was high GOT1 expression (P < 0.05 for both EFS and OS). Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis showed that the genes related to GOT1 expression were mainly concentrated in “hematopoietic cell lineage” and “leukocyte transendothelial migration” signaling pathways. Collectively, GOT1 expression may be a useful prognostic indicator in AML, especially in patients who have undergone allo-HSCT.

Elevated Expression of Inhibitor of Apoptosis-stimulating Protein of p53 (iASPP) and Methyltransferase-like 3 (METTL3) Correlate with Poor Prognosis in FIGO Ib1-IIa Squamous Cell Cervical Cancer

Background: Clinical outcomes of patients with early stage cervical cancer are determined by unique molecular events. Therefore, exploring novel biomarkers for the diagnosis and prognosis of cervical cancer is essential for guidance of cervical cancer treatment.

Methods: Patients with FIGO Ib1-IIa cervical cancer who were treated with radical hysterectomy at the first affiliated hospital of Guangxi Medical University, China were included in the study. iASPP and METTL3 expression in the tumor specimens and adjacent non-tumor cervical tissues was determined by immunohistochemistry and western blot, and its relationship with clinicopathologic factors and prognosis of cervical cancer patients was analyzed.

Results: Of 112 patients, 41 were stage Ib1, 22 Ib2, and 49 IIa. Their mean age was 45.3 years (range 25-75 years). Tumor size was 0.3 to 5.0 cm (mean 2.8 cm). Mean follow-up was 56.6 months (range 19-72 months). iASPP and METTL3 were higher in cervical cancer than normal cervix samples (p<0.001 and p<0.01, respectively). iASPP and METTL3 overexpression correlated with higher FIGO staging (p=0.013 and p=0.039, respectively), pelvic lymph node metastasis (p=0.002 and p=0.001, respectively), and poor 5-year recurrence-free survival, distant metastasis-free survival, progression-free survival, and overall survival rates (p=0.002, p=0.007, p=0.001, p=0.016, p=0.001, p<0.001, p=0.037, and p=0.042, respectively). High iASPP and METTL3 expression were independent prognostic factors (all p<0.05). The expression of iASPP was positively related with METTL3 (p=0.002).

Conclusions: iASPP and METTL3 levels were elevated in cervical cancer, and they were both independent indicators for poor prognosis in early stage cervical cancer patients.

Prognostic role of SCAMP family in acute myeloid leukemia

Acute myeloid leukemia (AML) is a malignant disease of myeloid hematopoietic stem or progenitor cells characterized by abnormal proliferation of primary and immature myeloid cells in bone marrow and peripheral blood. Gene mutation and expression profiles can be used as prognosis predictors for different prognostic subgroups. Secretory carrier-associated membrane proteins (SCAMPs) are a multigenic family with five members and act as cell surface vectors in the post-Golgi recycling pathways in mammals. Nevertheless, the prognostic and clinical influence of SCAMP family has hardly ever been illustrated in AML. In our study, expression patterns of SCAMP family (SCAMP1-5) were analyzed in 155 AML patients which were extracted from the Cancer Genome Atlas database. In chemotherapy, only subgroup, higher SCAMP1 level was significantly associated with longer EFS and OS (all P = 0.002), and SCAMP1 was confirmed to be an independent favorable factor in un-transplanted patients by Multivariate analysis (all P < 0.05). Nevertheless, in the allogeneic hematopoietic stem cell transplantation (allo-HSCT) treatment subgroup, none of the SCAMP genes had any effect on the clinical survival. Our study found that high expression level of SCAMP1 is a favorable prognostic factor in AML, but allo-HSCT may neutralize its prognostic effect.

Up-regulation of DDIT4 predicts poor prognosis in acute myeloid leukaemia

The mammalian target of rapamycin (mTOR) inhibitor, DNA damage inducible transcript 4 (DDIT4), has inducible expression in response to various cellular stresses. In multiple malignancies, studies have shown that DDIT4 participates in tumorigenesis and impacts patient survival. We aimed to study the prognostic value of DDIT4 in acute myeloid leukaemia (AML), which is currently unclear. Firstly, The Cancer Genome Atlas was screened for AML patients with complete clinical characteristics and DDIT4 expression data. A total of 155 patients were included and stratified according to the treatment modality and the median DDIT4 expression levels. High DDIT4 expressers had shorter overall survival (OS) and event‐free survival (EFS) than the low expressers among the chemotherapy‐only group (all P < .001); EFS and OS were similar in the high and low DDIT4 expressers of the allogeneic haematopoietic stem cell transplantation (allo‐HSCT) group. Furthermore, in the DDIT4^high group, patients treated with allo‐HSCT had longer EFS and OS than those who received chemotherapy alone (all P < .01). In the DDIT4^low group, OS and EFS were similar in different treatment groups. Secondly, we analysed two other cytogenetically normal AML (CN‐AML) cohorts derived from the Gene Expression Omnibus database, which confirmed that high DDIT4 expression was associated with poorer survival. Gene Ontology (GO) enrichment analysis showed that the genes related to DDIT4 expression were mainly concentrated in the acute and chronic myeloid leukaemia signalling pathways. Collectively, our study indicates that high DDIT4 expression may serve as a poor prognostic factor for AML, but its prognostic effects could be outweighed by allo‐HSCT.

Role of FHL2 in digestive system malignancies

FHL2 is a scaffold protein that regulates signal transduction and gene transcription, and it has typical structural features of FHL proteins. Each FHL protein contains four half-LIM domains, and different LIM domains can bind to different proteins, which can activate or inhibit the activities of transcription factors such as P53 and serum response factors, and then influences the development of tumors. Previous studies have found that FHL2 has a complex biological role in tumorigenesis, and may promote or suppress tumor development in different types of tumors. In this article, we review the role of FHL2 in digestive system malignancies.

iASPP mediates p53 selectivity through a modular mechanism fine-tuning DNA recognition

The most frequently mutated protein in human cancer is p53, a transcription factor (TF) that regulates myriad genes instrumental in diverse cellular outcomes including growth arrest and cell death. Cell context-dependent p53 modulation is critical for this life-or-death balance, yet remains incompletely understood. Here we identify sequence signatures enriched in genomic p53-binding sites modulated by the transcription cofactor iASPP. Moreover, our p53-iASPP crystal structure reveals that iASPP displaces the p53 L1 loop-which mediates sequence-specific interactions with the signature-corresponding base-without perturbing other DNA-recognizing modules of the p53 DNA-binding domain. A TF commonly uses multiple structural modules to recognize its cognate DNA, and thus this mechanism of a cofactor fine-tuning TF-DNA interactions through targeting a particular module is likely widespread. Previously, all tumor suppressors and oncoproteins that associate with the p53 DNA-binding domain-except the oncogenic E6 from human papillomaviruses (HPVs)-structurally cluster at the DNA-binding site of p53, complicating drug design. By contrast, iASPP inhibits p53 through a distinct surface overlapping the E6 footprint, opening prospects for p53-targeting precision medicine to improve cancer therapy.

High EGFL7 expression may predict poor prognosis in acute myeloid leukemia patients undergoing allogeneic hematopoietic stem cell transplantation

Epithelial growth factor-like 7 (EGFL7) is a secretory protein with a well-characterized role in angiogenesis and the oncogenesis of certain solid tumors. Overexpression of EGFL7 is associated with adverse prognosis in patients with cytogenetically normal acute myeloid leukemia (CN-AML). However, whether this association persists after allogeneic hematopoietic stem cell transplantation (allo-HSCT) remains unclear. To further clarify the prognostic role of EGFL7, seventy-one AML patients with EGFL7 expression data who underwent allo-HSCT from The Cancer Genome Atlas database were included and divided into either EGFL7^high or EGFL7^low group based on the median EGFL7 expression level. Two groups had similar clinical and molecular characteristics except that the EGFL7^high group had less frequent NPM1 mutations (P= .001). Kaplan-Meier survival curves showed that high EGFL7 expressers had shorter OS than the low expressers (P= .040). Univariate analysis showed that high EGFL7 expression, MLL-PTD, RUNX1 and TP53 mutations were associated with short OS (all P< .05). Multivariate analysis indicated that high EGFL7 expression, FLT3-ITD, RUNX1 and TP53 mutations were independent risk factors for OS (all P< .05). Collectively, our study suggested that EGFL7, like the other widely-used risk stratification factors, could serve as a prognostic tool and therapeutic target in AML, even after allo-HCST.

Prognostic value of the FUT family in acute myeloid leukemia

Genetic abnormalities are more frequently viewed as prognostic markers in acute myeloid leukemia (AML) in recent years. Fucosylation, catalyzed by fucosyltransferases (FUTs), is a post-translational modification that widely exists in cancer cells. However, the expression and clinical implication of the FUT family (FUT1-11) in AML has not been investigated. From the Cancer Genome Atlas database, a total of 155 AML patients with complete clinical characteristics and FUT1-11 expression data were included in our study. In patients who received chemotherapy alone showed that high expression levels of FUT3, FUT6, and FUT7 had adverse effects on event-free survival (EFS) and overall survival (OS) (all P < 0.05), whereas high FUT4 expression had favorable effects on EFS and OS (all P < 0.01). However, in the allogeneic hematopoietic stem cell transplantation (allo-HSCT) group, we only found a significant difference in EFS between the high and low FUT3 expression subgroups (P = 0.047), while other FUT members had no effect on survival. Multivariate analysis confirmed that high FUT4 expression was an independent favorable prognostic factor for both EFS (HR = 0.423, P = 0.001) and OS (HR = 0.398, P < 0.001), whereas high FUT6 expression was an independent risk factor for both EFS (HR = 1.871, P = 0.017) and OS (HR = 1.729, P = 0.028) in patients who received chemotherapy alone. Moreover, we found that patients with low FUT4 and high FUT6 expressions had the shortest EFS and OS (P < 0.05). Our study suggests that high expressions of FUT3/6/7 predict poor prognosis, high FUT4 expression indicates good prognosis in AML; FUT6 and FUT4 have the best prognosticating profile among them, but their effects could be neutralized by allo-HSCT.

High IFITM3 expression predicts adverse prognosis in acute myeloid leukemia

Acute myeloid leukemia (AML) is a malignancy caused by the uncontrolled and dysregulated clonal expansion of abnormal myeloid primordial cells. In general, the prognosis of AML remains poor despite new discoveries in its pathogenesis and treatment. It is crucial to find early and sensitive biomarkers and continue to explore active targeted treatments. Interferon-induced transmembrane protein (IFITM) family is an important part of the interferon signaling pathway and participate in the regulation of immune cell signaling, adhesion, cancer, and liver cell migration. However, the clinical and prognostic value of the IFITM family in AML has rarely been studied. We screened The Cancer Genome Atlas database and found 155 AML patients with IFITM family (IFITM1-5) expression data. In patients who only received chemotherapy, those with high IFITM3 expression had significantly shorter event-free survival (EFS) and overall survival (OS) than patients with low expression (all P < 0.05). Multivariate analysis demonstrated that high IFITM3 expression was an independent risk factor for EFS and OS in patients only received chemotherapy (all P < 0.05). In patients who underwent allogeneic hematopoietic stem cell transplantation (allo-HSCT), however, all IFITM members had no impact on either EFS or OS. In conclusion, our study elucidated that high IFITM3 expression could be an adverse prognostic factor for AML, whose effect might be overcome by allo-HSCT.

Prognostic significance of PAK family kinases in acute myeloid leukemia

Acute myeloid leukemia (AML) is a clonal and heterogeneous disease characterized by a myriad of genetic defects. Genetic abnormalities are powerful prognostic factors. P21-activated kinases (PAKs) are a kind of serine/threonine protein kinases, which is regulator of plenty of oncogenic signaling pathways. The clinical and prognostic value of PAKs in AML is unclear. A total of 155 AML patients with PAK expression data from The Cancer Genome Atlas database were enrolled in this study. Eighty-four patients underwent chemotherapy only, 71 also underwent allogeneic hematopoietic stem cell transplantation (allo-HSCT). In the chemotherapy-only group, high PAK3 and PAK7 expression were both bound up with poor EFS and OS (all P < 0.05). However, high PAK2 expressers had better EFS and OS (all P < 0.05). Multivariate analysis demonstrated that high PAK7 expression was an adverse independent prognostic factor in patients who received chemotherapy only. PAKs have no influence in EFS and OS in patients who underwent allo-HSCT. In conclusion, high PAK2 expression is a favorable prognostic factor, as to the high expression of PAK3 and PAK7, they are poor prognostic factors, and PAK7 has better prognostic value, but their prognostic effects can be offset by allo-HSCT.