Low expression of the FoxO4 gene may contribute to the phenomenon of EMT in non-small cell lung cancer

Downregulation of 4-HNE and FOXO4 collaboratively promotes NSCLC cell migration and tumor growth

Non-small cell lung cancer (NSCLC) is among the most prevalent cancers and a leading cause of cancer-related mortality globally. Extracellular vesicles (EVs) derived from NSCLC play a pivotal role in lung cancer progression. Our findings reveal a direct correlation between the abundance of EVs and the transfection efficiencies. Co-culturing two different lung cancer cell lines could enhance EVs formation, cell proliferation, migration and tumorigenicity. mRNA chip and metabolic analyses revealed significant alterations in the FOXO signaling pathway and unsaturated fatty acid metabolism within tumor tissues derived from co-cultured cells. Shotgun lipidomics studies and bioinformatics analyses guided our attention towards 4-Hydroxynonenal (4-HNE) and FOXO4. Elevating 4-HNE or FOXO4 levels could reduce the formation of EVs and impede cell growth and migration. While silencing FOXO4 expression lead to an increase in cell cloning rate and enhanced migration. These findings suggest that regulating the production of 4-HNE and FOXO4 might provide an effective therapeutic approach for the treatment of NSCLC.

The possible correlation between miR-762, Hippo signaling pathway, TWIST1, and SMAD3 in lung cancer and chronic inflammatory diseases

MicroRNAs are small RNA molecules that have a significant role in translational repression and gene silencing through binding to downstream target mRNAs. MiR-762 can stimulate the proliferation and metastasis of various types of cancer. Hippo pathway is one of the pathways that regulate tissue development and carcinogenesis. Dysregulation of this pathway plays a vital role in the progression of cancer. This study aimed to evaluate the possible correlation between miR-762, the Hippo signaling pathway, TWIST1, and SMAD3 in patients with lung cancer, as well as patients with chronic inflammatory diseases. The relative expression of miR-762, MST1, LATS2, YAP, TWIST1, and SMAD3 was determined in 50 lung cancer patients, 30 patients with chronic inflammatory diseases, and 20 healthy volunteers by real-time PCR. The levels of YAP protein and neuron-specific enolase were estimated by ELISA and electrochemiluminescence immunoassay, respectively. Compared to the control group, miR-762, YAP, TWIST1, and SMAD3 expression were significantly upregulated in lung cancer patients and chronic inflammatory patients, except SMAD3 was significantly downregulated in chronic inflammatory patients. MST1, LATS2, and YAP protein were significantly downregulated in all patients. MiR-762 has a significant negative correlation with MST1, LATS2, and YAP protein in lung cancer patients and with MST1 and LATS2 in chronic inflammatory patients. MiR-762 may be involved in the induction of malignant behaviors in lung cancer through suppression of the Hippo pathway. MiR-762, MST1, LATS2, YAP mRNA and protein, TWIST1, and SMAD3 may be effective diagnostic biomarkers in both lung cancer patients and chronic inflammatory patients. High YAP, TWIST1, SMA3 expression, and NSE level are associated with a favorable prognosis for lung cancer.

Diverse activity of miR-150 in Tumor development: shedding light on the potential mechanisms

There is a growing interest to understand the role and mechanism of action of microRNAs (miRNAs) in cancer. The miRNAs are defined as short non-coding RNAs (18-22nt) that regulate fundamental cellular processes through mRNA targeting in multicellular organisms. The miR-150 is one of the miRNAs that have a crucial role during tumor cell progression and metastasis. Based on accumulated evidence, miR-150 acts as a double-edged sword in malignant cells, leading to either tumor-suppressive or oncogenic function. An overview of miR-150 function and interactions with regulatory and signaling pathways helps to elucidate these inconsistent effects in metastatic cells. Aberrant levels of miR-150 are detectable in metastatic cells that are closely related to cancer cell migration, invasion, and angiogenesis. The ability of miR-150 in regulating of epithelial-mesenchymal transition (EMT) process, a critical stage in tumor cell migration and metastasis, has been highlighted. Depending on the cancer cells type and gene expression profile, levels of miR-150 and potential target genes in the fundamental cellular process can be different. Interaction between miR-150 and other non-coding RNAs, such as long non-coding RNAs and circular RNAs, can have a profound effect on the behavior of metastatic cells. MiR-150 plays a significant role in cancer metastasis and may be a potential therapeutic target for preventing or treating metastatic cancer.

Mapping Multi-factor-mediated Chromatin Interactions to Assess Dysregulation of Lung Cancer-related Genes

Studies on the lung cancer genome are indispensable for developing a cure for lung cancer. Whole-genome resequencing, genome-wide association studies, and transcriptome sequencing have greatly improved our understanding of the cancer genome. However, dysregulation of long-range chromatin interactions in lung cancer remains poorly described. To better understand the three-dimensional (3D) genomic interaction features of the lung cancer genome, we used the A549 cell line as a model system and generated high-resolution chromatin interactions associated with RNA polymerase II (RNAPII), CCCTC-binding factor (CTCF), enhancer of zeste homolog 2 (EZH2), and histone 3 lysine 27 trimethylation (H3K27me3) using long-read chromatin interaction analysis by paired-end tag sequencing (ChIA-PET). Analysis showed that EZH2/H3K27me3-mediated interactions further repressed target genes, either through loops or domains, and their distributions along the genome were distinct from and complementary to those associated with RNAPII. Cancer-related genes were highly enriched with chromatin interactions, and chromatin interactions specific to the A549 cell line were associated with oncogenes and tumor suppressor genes, such as additional repressive interactions on FOXO4 and promoter-promoter interactions between NF1 and RNF135. Knockout of an anchor associated with chromatin interactions reversed the dysregulation of cancer-related genes, suggesting that chromatin interactions are essential for proper expression of lung cancer-related genes. These findings demonstrate the 3D landscape and gene regulatory relationships of the lung cancer genome.

The role of miRNA-128 in the development and progression of gastrointestinal and urogenital cancer

Increasing data have shown the significance of various miRNAs in malignancy. In this regard, parallel to its biological role in normal tissues, miRNA-128 (miR-128) has been found to play an essential immunomodulatory function in the process of cancer initiation and development. The occurrence of the aberrant expression of miR-128 in tumors and the unique properties of miRNAs raise the prospect of their use as biomarkers and the next generation of molecular anticancer therapies. The function of miR-128 in malignancies such as breast, prostate, colorectal, gastric, pancreatic, esophageal, cervical, ovarian and bladder cancers and hepatocellular carcinoma is discussed in this review. Finally, the effect of exosomal miR-128 on cancer resistance to therapeutics and cancer immunotherapy in certain malignancies is highlighted.

Correlations of ALD, Keap-1, and FoxO4 expression with traditional tumor markers and clinicopathological characteristics in colorectal carcinoma

Aldolase A (A-2) (ALD), Kelch-like-ECH associated protein-1 (Keap-1), and Forkhead box O4 (FoxO4) are key regulatory proteins, which have been proven to be involved in tumor development. However, the clinicopathological significance of ALD, Keap-1, and FoxO4 expressions in colorectal (colon) carcinoma (CRC) is not clearly known. We sought to explore the clinicopathological significance of ALD, Keap-1, and FoxO4 in CRC to provide evidences for potential monitoring index of CRC. Cases of 199 CRC patients were analyzed retrospectively. Evaluation of ALD, cAMP response element-binding protein-2, cyclo-oxygenase 2, FoxO4, Keap-1, and p53 expressions in CRC patients was accomplished with immunohistochemical technique. The patients were divided into negative and positive groups in accordance with immunohistochemical result. We compared the clinicopathological characteristics of the patients in the 2 groups, coupled with analysis of the relationship between 6 aforesaid proteins and clinicopathological characteristics. Herein, we confirmed the association of tumor location with the expression of ALD, Keap-1, and FoxO4. Also, tumor differentiation was observed to associate significantly with the expression of Keap-1, FoxO4, and Cox-2. The data also revealed that there was a correlation between smoking and expression of ALD, Keap-1, FoxO4, p53, and Cox-2. Nevertheless, insignificant difference was observed when clinicopathological characteristics were compared with cAMP response element-binding protein-2 expression. These findings suggest that ALD, Keap-1, and FoxO4 reinvolved in CRC development, and thus may be considered as potential monitoring protein for CRC.

Diverse roles of FOXO family members in gastric cancer

Gastric cancer (GC) is the fifth most diagnosed cancer and the third leading cause of cancer-related death worldwide. Although progress has been made in diagnosis, surgical resection, systemic chemotherapy, and immunotherapy, patients with GC still have a poor prognosis. The overall 5-year survival rate in patients with advanced GC is less than 5%. The FOXO subfamily, of the forkhead box family of transcription factors, consists of four members, FOXO1, FOXO3, FOXO4, and FOXO6. This subfamily plays an important role in many cellular processes, such as cell cycle, cell growth, apoptosis, autophagy, stress resistance, protection from aggregate toxicity, DNA repair, tumor suppression, and metabolism, in both normal tissue and malignant tumors. Various studies support a role for FOXOs as tumor suppressors based on their ability to inhibit angiogenesis and metastasis, and promote apoptosis, yet several other studies have shown that FOXOs might also promote tumor progression in certain circumstances. To elucidate the diverse roles of FOXOs in GC, this article systematically reviews the cellular functions of FOXOs in GC to determine potential therapeutic targets and treatment strategies for patients with GC.

Ubiquitin-specific protease 7 mediates platelet-derived growth factor-induced pulmonary arterial smooth muscle cells proliferation

Pulmonary arterial hypertension is a devastating pulmonary vascular disease, in which the pathogenesis is complicated and unclear. Pulmonary arterial smooth muscle cells (PASMCs) proliferation is a key pathological feature of pulmonary arterial hypertension. It has been shown that ubiquitin-specific protease 7 (USP7) is involved in cancer cell proliferation via deubiquitinating and stabilizing E3 ubiquitin ligase mouse double minute 2 (MDM2). However, the effect of USP7 and MDM2 on platelet-derived growth factor (PDGF)-induced PASMCs proliferation is uncertain. This study aims to explore this issue. Our results indicated that PDGF up-regulated USP7 protein expression and stimulated PASMCs proliferation; this was accompanied with the increase of MDM2, forkhead box O4 (FoxO4) reduction and elevation of CyclinD1. While prior transfection of USP7 siRNA blocked PDGF-induced MDM2 up-regulation, FoxO4 down-regulation, increase of CyclinD1 and cell proliferation. Pre-depletion of MDM2 by siRNA transfection reversed PDGF-induced reduction of FoxO4, up-regulation of CyclinD1 and PASMCs proliferation. Furthermore, pre-treatment of cells with proteasome inhibitor MG-132 also abolished PDGF-induced FoxO4 reduction, CyclinD1 elevation and cell proliferation. Our study suggests that USP7 up-regulates MDM2, which facilitates FoxO4 ubiquitinated degradation, and subsequently increases the expression of CyclinD1 to mediate PDGF-induced PASMCs proliferation.

Copper: An Intracellular Achilles' Heel Allowing the Targeting of Epigenetics, Kinase Pathways, and Cell Metabolism in Cancer Therapeutics

Copper is an essential transition metal frequently increased in cancer known to strongly influence essential cellular processes. Targeted therapy protocols utilizing both novel and repurposed drug agents initially demonstrate strong efficacy, before failing in advanced cancers as drug resistance develops and relapse occurs. Overcoming this limitation involves the development of strategies and protocols aimed at a wider targeting of the underlying molecular changes. Receptor Tyrosine Kinase signaling pathways, epigenetic mechanisms and cell metabolism are among the most common therapeutic targets, with molecular investigations increasingly demonstrating the strong influence each mechanism exerts on the others. Interestingly, all these mechanisms can be influenced by intracellular copper. We propose that copper chelating agents, already in clinical trial for multiple cancers, may simultaneously target these mechanisms across a wide variety of cancers, serving as an excellent candidate for targeted combination therapy. This review summarizes the known links between these mechanisms, copper, and copper chelation therapy.

Exosomal miR-128-3p Promotes Epithelial-to-Mesenchymal Transition in Colorectal Cancer Cells by Targeting FOXO4 via TGF-β/SMAD and JAK/STAT3 Signaling

Epithelial-to-mesenchymal transition (EMT) is a key process that occurs during tumor metastasis, affecting a variety of malignancies including colorectal cancer (CRC). Exosomes mediate cell-cell communication by transporting cell-derived proteins and nucleic acids, including microRNAs (miRNAs). Exosomal delivery of miRNAs plays an important role in tumor initiation, development, and progression. In this study, we investigated the effect of exosomal transfer between CRC cells and aimed to identify specific miRNAs and downstream targets involved in EMT and metastasis in CRC cells. High expression of miR-128-3p was identified in exosomes derived from EMT-induced HCT-116 cells. Altered miR-128-3p expression in CRC cells led to distinct changes in proliferation, migration, invasion, and EMT. Mechanistically, miR-128-3p overexpression downregulated the expression of FOXO4 and induced the activation of TGF-β/SMAD and JAK/STAT3 signaling in CRC cells and xenografted tumors, which led to EMT. Clinically, high expression of miR-128-3p was significantly associated with perineural invasion, lymphovascular invasion, tumor stage, and CA 19-9 content in CRC patients. We revealed that exosomal miR-128-3p regulates EMT by directly suppressing its downstream target gene FOXO4 to activate TGF-β/SMAD and JAK/STAT3 signaling, and the properties of the miR-128-3p/FOXO4 axis were horizontally transferred via exosomal delivery. In turn, exosomal miR-128-3p could be considered as a new therapeutic vehicle for CRC.

FOXO4 Transactivation Domain Interaction with Forkhead DNA Binding Domain and Effect on Selective DNA Recognition for Transcription Initiation

Forkhead box O4 (FOXO4) is a human transcription factor (TF) that participates in cell homeostasis. While the structure and DNA binding properties of the conserved forkhead domain (FHD) have been thoroughly investigated, how the transactivation domain (TAD) regulates the DNA binding properties of the protein remains elusive. Here, we investigated the role of TAD in modulating the DNA binding properties of FOXO4 using solution NMR. We found that TAD and FHD form an intramolecular complex mainly governed by hydrophobic interaction. Remarkably, TAD and DNA share the same surface of FHD for binding. While FHD did not differentiate binding to target and non-target DNA, the FHD-TAD complex showed different behaviors depending on the DNA sequence. In the presence of TAD, free and DNA-bound FHD exhibited a slow exchange with target DNA and a fast exchange with non-target DNA. The interaction of the two domains affected the kinetic function of FHD depending on the type of DNA. Based on these findings, we suggest a transcription initiation model by which TAD modulates FOXO4 recognition of its target promoter DNA sequences. This study describes the function of TAD in FOXO4 and provides a new kinetic perspective on target sequence selection by TFs.

NCAPG Promotes The Proliferation Of Hepatocellular Carcinoma Through PI3K/AKT Signaling

Purpose

Studies show that high expression of non-SMC condensin I complex subunit G (NCAPG) is associated with many tumors. In this study, we explore the mechanism by which NCAPG promotes proliferation in hepatocellular carcinoma (HCC).

Patients and methods

Liver cancer and paracancerous tissue specimens of 90 HCC patients were collected, and expression levels of NCAPG in these tissues and cell lines were evaluated by Western blotting and immunohistochemistry. HCC cells were transfected with siRNAs and plasmids, and pathway activators or inhibitors were added. The 5-ethynyl-2ʹ-deoxyuridine (EdU) proliferation assay was used to measure cell proliferation. Flow cytometry was used to evaluate cell apoptosis. Western blot assays were performed as a standard procedure to detect total protein expression. Treated HCC cells were subcutaneously injected into nude mice.

Results

Analysis using the Oncomine database showed that NCAPG was upregulated in HCC and immunohistochemistry and Western blot assays showed it was upregulated in both HCC tissues and HCC cell lines. The overexpression of NCAPG could promote HCC cell proliferation and reduce HCC cell apoptosis. More importantly, RNA-sequencing analysis predicted that NCAPG plays a role in the HCC via PI3K-AKT signaling pathway. The PI3K/AKT/FOXO4 pathway was aberrantly activated, and the expressions of apoptosis-related protein were altered when NCAPG was overexpressed or silenced both in vitro and in vivo. LY294002, a PI3K inhibitor, could eliminate the NCAPG role of promoting HCC cell proliferation and reducing HCC cell apoptosis, while 740Y-P, a PI3K activator, contributed to the opposite effect.

Conclusion

NCAPG functions as an oncogene in HCC and plays a role in promoting cell proliferation and antiapoptosis through activating the PI3K/AKT/FOXO4 pathway.

Overexpression of fibronectin type III domain containing 3B is correlated with epithelial-mesenchymal transition and predicts poor prognosis in lung adenocarcinoma

Fibronectin (FN) type III domain containing 3B (FNDC3B), a member of the FN family, regulates the invasion and metastasis of cells in numerous tumor types. However, the mechanisms through which FNDC3B regulates carcinogenesis in lung adenocarcinoma (LADC) tissues have remained elusive. The present study revealed that the protein levels of FNDC3B and vimentin were significantly elevated in LADC tissues compared with those in normal lung tissues. By contrast, the expression of E-cadherin was decreased in LADC tissues compared with that in normal lung tissues. Furthermore, the aberrant expression of FNDC3B and epithelial-mesenchymal transition (EMT) markers was significantly associated with histological differentiation, lymph node metastasis and tumor-nodes-metastasis stage. Kaplan-Meier analysis indicated that a high expression of FNDC3B may be associated with poor overall survival of patients with LADC. In addition, overexpression of FNDC3B promoted the protein expression of EMT-associated genes in the A549 lung adenocarcinoma cell line. In conclusion, the present results support the notion that FNDC3B acts as an oncogene in LADC; it may serve a pivotal role in the development and progression of LADC and may participate in the regulation of the EMT.

Forkhead box O4 transcription factor in human neoplasms: Cannot afford to lose the novel suppressor

Forkhead box O4 (FOXO4), a member of FOXO family, has been highlighted as an essential transcriptional regulator in many diverse carcinomas. Accumulated studies have demonstrated that FOXO4 is downregulated and associated with tumorigenesis, invasiveness, and metastasis of most human cancer. FOXO4 alteration is also closely linked to the prognosis of various types of cancer. The aim of this review is to comprehensively present the clinical and pathological significance of FOXO4 in human cancer. Additionally, the potential clinical applications of future FOXO4 research are discussed. Collectively, the information reviewed here should increase the potential of FOXO4 as a therapeutic target for cancer.

Hsa_circRNA_103809 regulated the cell proliferation and migration in colorectal cancer via miR-532-3p / FOXO4 axis

Circular RNAs(circRNAs) are a class of non-coding RNAs that are widely expressed in a variety of cell species. The role they play in cancers is poorly understood, especially in colorectal cancer (CRC). Hsa_circRNA_103809 (hsa_circ_0072088, circZFR)has been demonstrated to be lowly expressed in colorectal cancer tissues and is associated with stage and lymph node metastasis of cancer tissues. Real-time quantitative PCR (qRT-PCR) was used to verify the relationship of hsa_circRNA_103809 between colorectal cancer and paired adjacent tissue in clinical tissue samples. Then, the proliferative capacity, migration ability, cell cycle, and apoptosis were measured using wound-healing assay, CCK8, transwell assay, flow cytometry, and the like, when hsa_circRNA_103809 expression in SW620 and COCA-2. The qRT-PCR, western bolt and other experiments verify that the expression of hsa_circRNA_103809 can regulate the expression of miR-532-3P and FOXO4. Hsa_circRNA_103809 was found to be significantly down regulated in CRC tissues and cell lines and compared with paired adjacent non-tumorous tissues and normal FHC cells. Hsa_circRNA_103809 participates in the regulation of biological functions through the miR-532-3P/FOXO4 axis in the CRC. Hsa_circRNA_103809 may be a potential novel gene target for the diagnosis and treatment of CRC.

Role of Forkhead Box Class O proteins in cancer progression and metastasis

It is now widely accepted that several gene alterations including transcription factors are critically involved in cancer progression and metastasis. Forkhead Box Class O proteins (FoxOs) including FoxO1/FKHR, FoxO3/FKHRL1, FoxO4/AFX and FoxO6 transcription factors are known to play key roles in proliferation, apoptosis, metastasis, cell metabolism, aging and cancer biology through their phosphorylation, ubiquitination, acetylation and methylation. Though FoxOs are proved to be mainly regulated by upstream phosphatidylinositol-4,5-bisphosphate 3-kinase (PI3 K)/Akt signaling pathway, the role of FoxOs in cancer progression and metastasis still remains unclear so far. Thus, with previous experimental evidences, the present review discussed the role of FoxOs in association with metastasis related molecules including cannabinoid receptor 1 (CNR1), Cdc25A/Cdk2, Src, serum and glucocorticoid inducible kinases (SGKs), CXCR4, E-cadherin, annexin A8 (ANXA8), Zinc finger E-box-binding homeobox 2 (ZEB2), human epidermal growth factor receptor 2 (HER2) and mRNAs such as miR-182, miR-135b, miR-499-5p, miR-1274a, miR-150, miR-34b/c and miR-622, subsequently analyzed the molecular mechanism of some natural compounds targeting FoxOs and finally suggested future research directions in cancer progression and metastasis.

FOXO3a expression is associated with lymph node metastasis and poor disease-free survival in triple-negative breast cancer

Aims

Forkhead box O (FOXO) transcription factors, consisting of FOXO1, FOXO3a, FOXO4 and FOXO6, are involved in carcinogenesis and tumour progression. Recent studies have suggested that FOXOs act as tumour suppressors in a variety of human cancers. This study investigated the clinicopathological significance of FOXOs in triple-negative breast cancer (TNBC).

Methods

FOXO protein expressions were assessed by immunohistochemistry in 125 TNBC tissues. Correlations between FOXO protein expression and various clinicopathological parameters, including patients’ survival, were investigated. MDA-MB-468 cell line was used for in vitro cell proliferation and migration assay.

Results

FOXO1 protein expression was not observed in all 125 TNBC tissues. FOXO4 and FOXO6 protein expressions were detected in 11 (8.8%) and 14 (11.2%) TNBC tissues, respectively. Loss of FOXO4 expression was significantly associated with high histological grade (P=0.014, χ2 test), and TNBCs with positive FOXO6 expression correlated with high grade (P=0.020, χ2 test). FOXO3a expression was detected in 40 (32%) TNBC cases and correlated with adverse clinicopathological features, such as lymph node metastasis (P=0.021, χ2 test), perineural invasion (P=0.013, χ2 test) and higher Ki-67 proliferation index (P=0.048, t-test). Additionally, FOXO3a expression was significantly associated with poor disease-free survival (P=0.015, log-rank test). In the in vitro study, siRNA-mediated FOXO3a knockdown in the MDA-MB-468 cell line inhibited cell proliferation and migration.

Conclusion

Among FOXO members, FOXO3a may have a potential role in promoting tumour cell migration and proliferation and may serve as a prognostic biomarker and a potential therapeutic target for TNBC.

Forkhead box O proteins: Crucial regulators of cancer EMT

The epithelial-mesenchymal transition (EMT) is an acknowledged cellular transition process in which epithelial cells acquire mesenchymal-like properties that endow cancer cells with increased migratory and invasive behavior. Forkhead box O (FOXO) proteins have been shown to orchestrate multiple EMT-associated pathways and EMT-related transcription factors (EMT-TFs), thereby modulating the EMT process. The focus of the current review is to evaluate the latest research progress regarding the roles of FOXO proteins in cancer EMT. First, a brief overview of the EMT process in cancer and a general background on the FOXO family are provided. Next, we present the interactions between FOXO proteins and multiple EMT-associated pathways during malignancy development. Finally, we propose several novel potential directions for future research. Collectively, the information compiled herein should serve as a comprehensive repository of information on this topic and should aid in the design of additional studies and the future development of FOXO proteins as therapeutic targets.

FOXO4 and FOXD3 are predictive of prognosis in gastric carcinoma patients

Forkhead box (FOX) transcription factor family plays an important role in cancer growth and metastasis. This study aimed to determine the predictive ability of FOX genes in gastric carcinoma. A total of 360 patients with gastric from The Cancer Genome Atlas (TCGA) cohorts were collected in this study. The expression profile of FOX family were obtained from the TCGA RNAseq database. Clinicopathological characteristics, including age, gender, tumor node metastasis (TNM), tumor grade, and overall survival were collected. Univariate and multivariate Cox proportional hazards model were used to assess the risk factors for survival, and the results were further validated in in-house cohort. In the TCGA cohort, FOXO4 (HR = 0.613, 95%CI 0.452–0.832) and FOXD3 (HR = 1.704, 95%CI 1.212–2.397) were shown independently predictive of overall survival in gastric cancer after Cox proportional hazards analysis. The finding was validated in our in-house cohort, which demonstrated that both FOXO4 and FOXD3 were independent predictors for overall survival (FOXO4 high, HR: 0.445, 95%CI 0.277–0.715, P = 0.001, FOXD3 high, HR: 1.927, 95%CI 1.212–3.063, P = 0.006) and disease free survival (FOXO4 high, HR: 0.628, 95%CI 0.420–0.935, P = 0.022, FOXD3 high, HR: 1.698, 95%CI 1.136–2.540, P = 0.010). Collectively, FOX family paly critical roles in gastric cancer, and FOXO4 and FOXD3 were identified as independent prognostic factors for survival outcomes of gastric cancer. Further functional study is needed to understand more about FOX family in gastric cancer.

miR‑138 modulates prostate cancer cell invasion and migration via Wnt/β‑catenin pathway

The prognosis for prostate cancer patients with distant metastasis is poor, with an average survival rate of 24‑48 months. The exact mechanisms underlying prostate cancer metastasis remain to be elucidated, despite previous research efforts. The present study aimed to reveal the regulatory roles of miR‑138 via Wnt/β‑catenin pathway in prostate cancer cell migration and invasion. Reverse transcription‑quantitative polymerase chain reaction was used to examine the mRNA and protein expression levels and transwell assay was conducted to determine cell invasion and migration. A luciferase reporter assay was used to determine the target association between miR‑138 and β‑catenin. The present study identified microRNA (miR)‑138 as an invasion and migration regulator in prostate cancer. miR‑138 was downregulated in aggressive prostate cancer cell lines. Furthermore, followingmiR‑138 overexpression, prostate cancer cells exhibited impaired invasive and migratory abilities. E‑cadherin was upregulated and vimentin was downregulated. In addition, it was demonstrated that miR‑138 negatively regulated the Wnt/β‑catenin pathway activation in prostate cancer. The pathway was then activated via β‑catenin overexpression and this reversed the effects of miR‑138. The results suggest that miR‑138 downregulation may contribute to prostate cancer progression and metastasis. The findings provide a novel molecular therapeutic target in the treatment of prostate cancer metastasis.

FOXO Transcriptional Factors and Long-Term Living

Several pathologies such as neurodegeneration and cancer are associated with aging, which is affected by many genetic and environmental factors. Healthy aging conceives human longevity, possibly due to carrying the defensive genes. For instance, FOXO (forkhead box O) genes determine human longevity. FOXO transcription factors are involved in the regulation of longevity phenomenon via insulin and insulin-like growth factor signaling. Only one FOXO gene (FOXO DAF-16) exists in invertebrates, while four FOXO genes, that is, FOXO1, FOXO3, FOXO4, and FOXO6 are found in mammals. These four transcription factors are involved in the multiple cellular pathways, which regulate growth, stress resistance, metabolism, cellular differentiation, and apoptosis in mammals. However, the accurate mode of longevity by FOXO factors is unclear until now. This article describes briefly the existing knowledge that is related to the role of FOXO factors in human longevity.

Expression of Kruppel-like factor 8 and Ki67 in lung adenocarcinoma and prognosis

Kruppel-like factor 8 (KLF8) belongs to the KLF family and has various roles in the regulation of the cell cycle, proliferation and tumor genesis. KLF8 is overexpressed in gastric, ovarian, breast and renal cancer. Additionally, KLF8 may affect invasion and metastasis of tumors. However, whether KLF8 also acts as an ontogeny in lung adenocarcinoma (LAC) remains unknown. The aim of the present study was to determine the association between KLF8 expression and various clinical and pathological parameters. Western blot assays and immune histochemistry analyses revealed that KLF8 level in LAC tissues was higher than that in the normal lung tissues and KLF8 expression was significantly associated with clinical variables (P<0.05). Kaplan-Meier curves revealed that high expression of KLF8 was related to poor prognosis in patients with LAC. The present study also demonstrated that KLF8 was involved in the progression of lung adenocarcinoma. This data suggested that KLF8 may act as a prognostic factor in lung adenocarcinoma progression.

Effect of AXL on the epithelial-to-mesenchymal transition in non-small cell lung cancer

Non-small-cell lung cancer (NSCLC) is the leading cause of cancer-associated mortality in the United States. AXL, which is a member of the receptor tyrosine kinases, has been established as a strong candidate for the targeted therapy of cancer. Therefore, the present study aimed to investigate the role of AXL in NSCLC; in particular the molecular mechanisms underlying the involvement of AXL in the epithelial-to-mesenchymal transition (EMT). Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and western blot analysis demonstrated that AXL, EMT-inducing Twist and the mesenchymal marker N-cadherin were upregulated, and the epithelial markers E-cadherin and β-cadherin were downregulated, in the PC9 NSCLC cell line. Furthermore, downregulation of AXL expression by RNA interference was shown to inhibit cell growth by inducing the apoptosis of PC9 cells, as demonstrated by MTT and flow cytometry analyses. Notably, inhibition of AXL attenuated the regulation of EMT-associated genes, specifically downregulating Twist and N-cadherin, and upregulating E-cadherin and β-cadherin. Conversely, downregulation of Twist did not affect the expression levels of AXL. These results suggested that AXL may inhibit the EMT by the regulation of EMT-associated genes in the PC9 cell line. The results of the present study indicated that AXL may have a role in the regulation of EMT and the cell cycle of the PC9 cells; thus suggesting that AXL may have clinical significance in the design of therapeutic strategies targeting NSCLC and EMT signaling pathways.

Prognostic Values of Vimentin Expression and Its Clinicopathological Significance in Non-Small Cell Lung Cancer: A Meta-Analysis of Observational Studies with 4118 Cases

BACKGROUND

Vimentin is a member of the intermediate filament proteins and a canonical marker of the epithelial-mesenchymal transition (EMT), which is pivotal in tumorigenesis, metastasis and invasion in non-small cell lung cancer (NSCLC). The current meta-analysis aimed to investigate the associations between vimentin and prognosis and progression in NSCLC.

METHODS

Databases with literature published in English, including PubMed, Web of Science, Embase, Science Direct, Wiley Online Library, Ovid, Cochrane Central Register of Controlled Trials, LILACS and Google Scholar, and the CNKI, VIP, CBM and WanFang databases in Chinese were used for the literature search. The key terms included (1) 'vimentin' OR 'vim' OR 'vmt' OR 'vm' OR 'hel113' OR 'ctrct30' and (2) 'pulmon*' OR 'lung' OR 'alveolar' and (3) 'cancer' OR 'carcinoma' OR 'tumor' OR 'adenocarcinoma' OR 'squamous' OR 'neoplas*' OR 'malignan*'. The data were combined by random effect model and the H value and I2 were used to assess the heterogeneity. All the meta-analysis was conducted using Stata 12.0.

RESULTS

Thirty-two qualified studies (4118 cases) were included in the current meta-analysis. Twelve studies with 1750 patients were included to assess the significance of vimentin in the overall survival (OS) of NSCLC; the pooled hazard ratio (HR) was 1.831 (confidence interval (CI): 1.315-2.550, P<0.001) in the univariate analysis and 1.266 (CI: 0.906-1.768, P = 0.167) in the multivariate analysis. Four studies with 988 cases were applicable to determine the significance of vimentin in the disease-free survival (DFS) of NSCLC; the pooled HR of the DFS was 1.224 (CI: 0.921-1.628, P = 0.164) in the univariate analysis and 1.254 (CI: 0.985-1.956, P = 0.067) in the multivariate analysis. Regarding the relationships between vimentin and clinicopathological factors, the pooled odds ratio (OR) with 3406 NSCLCs indicated that up-regulated vimentin was associated with smoking (OR = 1.359, CI: 1.098-1.683, P = 0.004), poor differentiation (OR = 2.133, CI: 1.664-2.735, P<0.001), an advanced TNM stage (OR = 3.275, CI: 1.987-5.397, P<0.001), vascular invasion (OR = 3.492, CI: 1.063-11.472, P = 0.039), lymph node metastasis (OR = 2.628, CI: 1.857-3.718, P<0.001), recurrence (OR = 1.631, CI: 1.052-2.528, P = 0.029) and pleural invasion (OR = 2.346, CI: 1.397-3.941, P = 0.001). There was no significant correlation between vimentin and age, gender, diameter, T stage, distant metastasis, or marginal invasion (P>0.05).

CONCLUSION

An overexpression of vimentin may predict the progression and an unfavorable survival of NSCLC. Vimentin may represent a helpful biomarker and a potential target for the treatment strategies of NSCLC. Additional, prospective studies with large samples are necessary to confirm the significance of vimentin in NSCLC.

Expression and prognostic value of E2F activators in NSCLC and subtypes: a research based on bioinformatics analysis

E2F activators (E2F1-3) codify a family of transcription factors (TFs) in higher eukaryotes. E2F activators are involved in the cell cycle regulation and synthesis of DNA in mammalian cells, and their overexpression has been detected in many human cancers. However, their clinical significance has not been deeply researched in non-small-cell lung cancer (NSCLC), and bioinformatics analysis has never been reported to explore their clinical role in NSCLC. In the current study, we investigated the expression and prognostic value of E2F activators in NSCLC patients through the "TCGA datasets" and the "Kaplan-Meier plotter" (KM plotter) database. Hazard ratio (HR), 95 % confidence intervals, and log-rank P were calculated. Compared with normal tissue samples, E2F activators were overexpressed in NSCLC tissues, in lung adenocarcinoma (LUAD) tissues, and in lung squamous cell carcinoma (LUSC) tissues. In NSCLC patients, E2F1 expression was significantly correlated with age, sex, and tumor stage. E2F2 expression was found to be significantly correlated with sex and tumor size. We further demonstrated that E2F1 and E2F2 overexpressions were significantly associated with poor prognosis. In LUAD patients, E2F1 expression was significantly correlated with tumor size and tumor stage. E2F2 expression was significantly correlated with lymph node status and tumor stage. E2F1 and E2F2 overexpression showed a significant association with poor prognosis, while E2F3 overexpression was significantly correlated to better prognosis. In LUSC patients, E2F1 was concluded to be significantly correlated with tumor stage. However, E2F activators were not found to be correlated to prognosis.

Murine double minute 2, a potential p53-independent regulator of liver cancer metastasis

Hepatocellular carcinoma (HCC) has emerged as one of the most commonly diagnosed forms of human cancer; yet, the mechanisms underlying HCC progression remain unclear. Unlike other cancers, systematic chemotherapy is not effective for HCC patients, while surgical resection and liver transplantation are the most viable treatment options. Thus, identifying factors or pathways that suppress HCC progression would be crucial for advancing treatment strategies for HCC. The murine double minute 2 (MDM2)-p53 pathway is impaired in most of the cancer types, including HCC, and MDM2 is overexpressed in approximately 30% of HCC. Overexpression of MDM2 is reported to be well correlated with metastasis, drug resistance, and poor prognosis of multiple cancer types, including HCC. Importantly, these correlations are observed even when p53 is mutated. Indeed, p53-independent functions of overexpressed MDM2 in cancer progression have been suitably demonstrated. In this review article, we summarize potential effectors of MDM2 that promote or suppress cancer metastasis and discuss the p53-independent roles of MDM2 in liver cancer metastasis from clinical as well as biological perspectives.

Down-regulation of MALAT1 inhibits cervical cancer cell invasion and metastasis by inhibition of epithelial-mesenchymal transition

The metastasis-associated lung adenocarcinoma transcript 1(MALAT1), a member of the long non-coding RNA (lncRNA) family, has been reported to be highly enriched in many kinds of cancers and to be a metastasis marker and a prognostic factor. In this study, we found that MALAT1 expression levels were significantly increased in cervical cancer (CC) cells and tissues. The down-regulation of MALAT1 by shRNA in CC cells inhibited the invasion and metastasis in vitro and in vivo. Microarray analysis showed that the knockdown of MALAT1 up-regulated the epithelial markers E-cadherin and ZO-1, and down-regulated the mesenchymal markers β-catenin and Vimentin. This regulation was further confirmed by subsequent observation from RT-PCR, western blot, and immunofluorescence results. Meanwhile, the transcription factor snail, which functions to modulate epithelial-mesenchymal transition (EMT), was also down-regulated at both transcript and protein levels by MALAT1 down-regulation. In addition, we found that MALAT1 expression levels were positively related to HPV infection in cervical epithelial tissues by microarray analysis. Taken together, these results suggest that MALAT1 functions to promote cervical cancer invasion and metastasis via induction of EMT, and it may be a target for the prevention and therapy of cervical cancers.

Identification of miRNAs and differentially expressed genes in early phase non-small cell lung cancer

To explore the potential therapeutic targets of early‑stage non-small cell lung cancer (NSCLC), gene microarray analysis was conducted. The microarray data of NSCLC in stage IA, IB, IIA, and IIB (GSE50081), were downloaded from the Gene Expression Omnibus (GEO) database. The differentially expressed genes (DEGs) in IB vs. IA, IIA vs. IB, IIB vs. IIA were screened out via R. ToppGene Suite was used to get the enriched Gene Ontology (GO) terms and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways of the DEGs. The GeneCoDis3 database and Cytoscape software were used to construct the transcriptional regulatory network. In total, 25, 17 and 14 DEGs were identified in IB vs. IA, IIA vs. IB, IIB vs. IIA of NSCLC, respectively. Some GO terms and pathways (e.g., extracellular space, alveolar lamellar body, bioactivation via cytochrome P450 pathway) were found significantly enriched in DEGs. Genes S100P, ALOX15B, CCL11, NLRP2, SERPINA3, FoxO4 and hsa-miR-491 may play important roles in the development of early-stage NSCLC. Thus, by bioinformatics analysis the key genes and biological processes involving in the development of early-stage NSCLC could be established, providing more potential references for the therapeutic targets.

Mechanisms of resistance to EGFR tyrosine kinase inhibitors

Since the discovery that non-small cell lung cancer (NSCLC) is driven by epidermal growth factor receptor (EGFR) mutations, the EGFR tyrosine kinase inhibitors (EGFR-TKIs, e.g., gefitinib and elrotinib) have been effectively used for clinical treatment. However, patients eventually develop drug resistance. Resistance to EGFR-TKIs is inevitable due to various mechanisms, such as the secondary mutation (T790M), activation of alternative pathways (c-Met, HGF, AXL), aberrance of the downstream pathways (K-RAS mutations, loss of PTEN), impairment of the EGFR-TKIs-mediated apoptosis pathway (BCL2-like 11/BIM deletion polymorphism), histologic transformation, ATP binding cassette (ABC) transporter effusion, etc. Here we review and summarize the known resistant mechanisms to EGFR-TKIs and provide potential targets for development of new therapeutic strategies.

The role of microRNA-1274a in the tumorigenesis of gastric cancer: accelerating cancer cell proliferation and migration via directly targeting FOXO4

MicroRNAs (miRNAs) are a series of 18-25 nucleotides length non-coding RNAs, which play critical roles in tumorigenesis. Previous study has shown that microRNA-1274a (miR-1274a) is upregulated in human gastric cancer. However, its role in gastric cancer progression remains poorly understood. Therefore, the current study was aimed to examine the effect of miR-1274a on gastric cancer cells. We found that miR-1274a was overexpressed in gastric cancer tissues or gastric cancer cells including HGC27, MGC803, AGS, and SGC-7901 by qRT-PCR analysis. Transfection of miR-1274a markedly promoted gastric cancer cells proliferation and migration as well as induced epithelial-mesenchymal transition (EMT) of cancer cells. Our further examination identified FOXO4 as a target of miR-1274a, which did not influence FOXO4 mRNA expression but significantly inhibited FOXO4 protein expression. Moreover, miR-1274a overexpression activated PI3K/Akt signaling and upregulated cyclin D1, MMP-2 and MMP-9 expressions. With tumor xenografts in mice models, we also showed that miR-1274a promoted tumorigenesis of gastric cancer in vivo. In all, our study demonstrated that miR-1274a prompted gastric cancer cells growth and migration through dampening FOXO4 expression thus provided a potential target for human gastric cancer therapy.