PRL-3 improves colorectal cancer cell proliferation and invasion through IL-8 mediated glycolysis metabolism

PRL-3: unveiling a new horizon in cancer therapy

PRL-3, a protein tyrosine phosphatase (PTP), has a significant influence on the pathogenesis of various cancers with its overexpression significantly correlating with tumor invasion, metastasis and poor prognosis. It significantly affects tumor cell behavior through its involvement in cell proliferation, migration and metabolic processes. Furthermore, the interaction between PRL-3 and the tumor microenvironment characterized by its adaptability to stress and its role in metabolic reprogramming enhances tumor cell survival and dissemination. Targeted therapies against PRL-3, encompassing small molecule inhibitors and the monoclonal antibody PRL-3-zumab, have shown promise in clinical and preclinical studies, presenting new avenues for cancer treatment. In addition, innovative approaches such as CAAX motif-targeting agents and PRL-3 degradation strategies hold promise for developing more precise and effective interventions. This review explores PRL-3's multifaceted roles across different tumor types and microenvironments, while discussing current and emerging therapeutic strategies aimed at exploiting its oncogenic potential.

Serum from Hypertensive Patients Induces Cancer-Supporting Phenotype of Vascular Endothelium In Vitro

BACKGROUND/OBJECTIVES

Large-scale epidemiological studies have established a bidirectional association between hypertension and cancer. However, the underlying mechanisms explaining this connection remain unclear. In our study, we investigated whether serum from patients with hypertension (HT) could enhance the aggressiveness of cancer cells in vitro through alterations in endothelial cell phenotype.

METHODS

Experiments were performed using EAhy926 endothelial cells and ovarian (SKOV-3), colorectal (SW480), pancreatic (PSN-1), breast (MCF-7), and lung (A549) cancer cell lines.

RESULTS

This study showed that conditioned medium (CM) produced by EAhy926 cells, when exposed to serum from patients with untreated hypertension (HT-CM), promotes the proliferation, migration, and invasion of every cancer cell line tested. In addition, endothelial cells subjected to HT serum promote the adhesion of all cancer cell types except PSN-1. An intensified transendothelial invasion of cancer cells was accompanied by decreased expression of junctional proteins (connexin 43, E-cadherin, occluding, desmoglein) in HT serum-treated endothelial cells. Quantitative analysis of the secretome of endothelial cells subjected to HT serum showed that they secrete increased amounts of CCL2, CXCL1, CXCL8, bFGF, HGF, IL-6, PAI-1, and TGF-β1. Moreover, cancer cells exposed to HT-CM display increased mRNA expression for several pro-cancerogenic agents, including CXCL8, tPA, and VEGF.

CONCLUSIONS

Our report shows that hypertension may potentiate cancer cell aggressiveness by modulating endothelial cell phenotype. Further tests with antihypertensive drugs are required to assess whether effective treatment of hypertension can mitigate its cancer-promoting potential.

Tumor-associated macrophages drive glycolysis through the IL-8/STAT3/GLUT3 signaling pathway in pancreatic cancer progression

Glycolytic metabolism is a hallmark of pancreatic ductal adenocarcinoma (PDAC), and tumor-associated stromal cells play important roles in tumor metabolism. We previously reported that tumor-associated macrophages (TAMs) facilitate PDAC progression. However, little is known about whether TAMs are involved in regulating glycolysis in PDAC. Here, we found a positive correlation between CD68+ TAM infiltration and FDG maximal standardized uptake (FDG SUVmax) on PET-CT images of PDAC. We discovered that the glycolytic gene set was prominently enriched in the high TAM infiltration group through Gene Set Enrichment Analysis using The Cancer Genome Atlas database. Mechanistically, TAMs secreted IL-8 to promote GLUT3 expression in PDAC cells, enhancing tumor glycolysis both in vitro and in vivo, whereas this effect could be blocked by the IL-8 receptor inhibitor reparixin. Furthermore, IL-8 promoted the translocation of phosphorylated STAT3 into the nucleus to activate the GLUT3 promoter. Overall, we demonstrated that TAMs boosted PDAC cell glycolysis through the IL-8/STAT3/GLUT3 signaling pathway. Our cumulative findings suggest that the abrogation of TAM-induced tumor glycolysis by reparixin might exhibit an antitumor impact and offer a potential therapeutic target for PDAC.

Protein Tyrosine Phosphatase PRL-3: A Key Player in Cancer Signaling

Protein phosphatases are primarily responsible for dephosphorylation modification within signal transduction pathways. Phosphatase of regenerating liver-3 (PRL-3) is a dual-specific phosphatase implicated in cancer pathogenesis. Understanding PRL-3's intricate functions and developing targeted therapies is crucial for advancing cancer treatment. This review highlights its regulatory mechanisms, expression patterns, and multifaceted roles in cancer progression. PRL-3's involvement in proliferation, migration, invasion, metastasis, angiogenesis, and drug resistance is discussed. Regulatory mechanisms encompass transcriptional control, alternative splicing, and post-translational modifications. PRL-3 exhibits selective expressions in specific cancer types, making it a potential target for therapy. Despite advances in small molecule inhibitors, further research is needed for clinical application. PRL-3-zumab, a humanized antibody, shows promise in preclinical studies and clinical trials. Our review summarizes the current understanding of the cancer-related cellular function of PRL-3, its prognostic value, and the research progress of therapeutic inhibitors.

The Crosstalk between Mesenchymal Stromal/Stem Cells and Hepatocytes in Homeostasis and under Stress

Liver diseases, characterized by high morbidity and mortality, represent a substantial medical problem globally. The current therapeutic approaches are mainly aimed at reducing symptoms and slowing down the progression of the diseases. Organ transplantation remains the only effective treatment method in cases of severe liver pathology. In this regard, the development of new effective approaches aimed at stimulating liver regeneration, both by activation of the organ's own resources or by different therapeutic agents that trigger regeneration, does not cease to be relevant. To date, many systematic reviews and meta-analyses have been published confirming the effectiveness of mesenchymal stromal cell (MSC) transplantation in the treatment of liver diseases of various severities and etiologies. However, despite the successful use of MSCs in clinical practice and the promising therapeutic results in animal models of liver diseases, the mechanisms of their protective and regenerative action remain poorly understood. Specifically, data about the molecular agents produced by these cells and mediating their therapeutic action are fragmentary and often contradictory. Since MSCs or MSC-like cells are found in all tissues and organs, it is likely that many key intercellular interactions within the tissue niches are dependent on MSCs. In this context, it is essential to understand the mechanisms underlying communication between MSCs and differentiated parenchymal cells of each particular tissue. This is important both from the perspective of basic science and for the development of therapeutic approaches involving the modulation of the activity of resident MSCs. With regard to the liver, the research is concentrated on the intercommunication between MSCs and hepatocytes under normal conditions and during the development of the pathological process. The goals of this review were to identify the key factors mediating the crosstalk between MSCs and hepatocytes and determine the possible mechanisms of interaction of the two cell types under normal and stressful conditions. The analysis of the hepatocyte-MSC interaction showed that MSCs carry out chaperone-like functions, including the synthesis of the supportive extracellular matrix proteins; prevention of apoptosis, pyroptosis, and ferroptosis; support of regeneration; elimination of lipotoxicity and ER stress; promotion of antioxidant effects; and donation of mitochondria. The underlying mechanisms suggest very close interdependence, including even direct cytoplasm and organelle exchange.

Warburg effect in colorectal cancer: the emerging roles in tumor microenvironment and therapeutic implications

Colorectal cancer (CRC) is the third most common cancer and the second leading cause of cancer-related death worldwide. Countless CRC patients undergo disease progression. As a hallmark of cancer, Warburg effect promotes cancer metastasis and remodels the tumor microenvironment, including promoting angiogenesis, immune suppression, cancer-associated fibroblasts formation and drug resistance. Targeting Warburg metabolism would be a promising method for the treatment of CRC. In this review, we summarize information about the roles of Warburg effect in tumor microenvironment to elucidate the mechanisms governing Warburg effect in CRC and to identify novel targets for therapy.

Monocyte Metabolism and Function in Patients Undergoing Cardiac Surgery

Objective

Cardiopulmonary bypass (CPB) can lead to systemic inflammation, which is associated with higher morbidity. Therefore, we investigated the metabolism of isolated blood monocytes before and after CPB compared to healthy controls.

Methods

In this prospective, monocentric, observational study, we included 30 patients undergoing CPB and 20 controls. We isolated monocytes from heparinized blood and investigated their metabolism by using Seahorse technology before (t0), 4 h (t4), and 24 h (t24) after the start of the CPB. We also examined programmed cell death 1 ligand (PD-L1), PD-L2, V-domain Ig suppressor of T cell activation (VISTA), and human leukocyte antigen-DR isotype (HLA-DR) using fluorescence-activated cell sorting analysis. Additionally, we investigated plasma cytokine levels in patients without and after ex vivo stimulation.

Results

CPB-induced inflammatory responses are shown by significantly elevated plasma interleukin-6 levels in the CPB group compared to baseline and controls [t0: 0 ng/ml (95%CI 0-0 ng/ml); t4: 0.16 ng/ml (95%CI 0.1-0.197 ng/ml), p < 0.0001; t24: 0.11 ng/ml (95% CI 0.1-0.16 ng/ml), p < 0.0001, and controls: 0 ng/ml (95% CI 0-0 ng/ml)]. The cytokine release in the ex vivo stimulation is reduced for lipopolysaccharide stimulation at t4 [t0: 35.68 ng/ml (95% CI 22.17-46.57 ng/ml) vs. t4: 15.02 (95% CI 10.25-24.78 ng/ml), p < 0.0001]. Intracellular metabolism of monocytes after CPB showed a protracted shift to aerobic glycolysis [t0: 179.2 pmol/min (95% CI 138.0-205.1 pmol/min) vs. t24: 250.1 pmol/min (95% CI 94.8-300.2 pmol/min), p < 0.0001]. Additionally, we observed an altered metabolism in monocytes in patients undergoing cardiac surgery compared to controls even before any surgical procedure [t0: 179.2 pmol/min (95% CI 138.0-205.1) vs. controls 97.4 (95% CI 59.13-144.6 pmol/min), p = 0.0031].

Conclusion

After CPB, patients' monocytes show a shift in metabolism from oxidative phosphorylation to aerobic glycolysis, which is associated with energy-demanding and proinflammatory processes. This is the first study to show changes in monocyte immunometabolism in cardiac surgery. Monocytes of patients undergoing cardiac surgery were leaning toward aerobic glycolysis even before any surgical procedure was conducted. Leaving the question of the pathophysiological mechanisms for future studies to be investigated and paving the way for potential therapy approaches preventing inflammatory effects of CPB.

Copy Number Alterations as Novel Biomarkers and Therapeutic Targets in Colorectal Cancer

In colorectal cancer, somatic mutations have played an important role as prognostic and predictive biomarkers, with some also functioning as therapeutic targets. Another genetic aberration that has shown significance in colorectal cancer is copy number alterations (CNAs). CNAs occur when a change to the DNA structure propagates gain/amplification or loss/deletion in sections of DNA, which can often lead to changes in protein expression. Multiple techniques have been developed to detect CNAs, including comparative genomic hybridization with microarray, low pass whole genome sequencing, and digital droplet PCR. In this review, we summarize key findings in the literature regarding the role of CNAs in the pathogenesis of colorectal cancer, from adenoma to carcinoma to distant metastasis, and discuss the roles of CNAs as prognostic and predictive biomarkers in colorectal cancer.

Metabolic Vulnerabilities in Multiple Myeloma

Multiple myeloma (MM) remains an incurable malignancy with eventual emergence of refractory disease. Metabolic shifts, which ensure the availability of sufficient energy to support hyperproliferation of malignant cells, are a hallmark of cancer. Deregulated metabolic pathways have implications for the tumor microenvironment, immune cell function, prognostic significance in MM and anti-myeloma drug resistance. Herein, we summarize recent findings on metabolic abnormalities in MM and clinical implications driven by metabolism that may consequently inspire novel therapeutic interventions. We highlight some future perspectives on metabolism in MM and propose potential targets that might revolutionize the field.

CXCL8 in Tumor Biology and Its Implications for Clinical Translation

The chemokine CXCL8 has been found to play an important role in tumor progression in recent years. CXCL8 activates multiple intracellular signaling pathways by binding to its receptors (CXCR1/2), and plays dual pro-tumorigenic roles in the tumor microenvironment (TME) including directly promoting tumor survival and affecting components of TME to indirectly facilitate tumor progression, which include facilitating tumor cell proliferation and epithelial-to-mesenchymal transition (EMT), pro-angiogenesis, and inhibit anti-tumor immunity. More recently, clinical trials indicate that CXCL8 can act as an independently predictive biomarker in patients receiving immune checkpoint inhibitions (ICIs) therapy. Preclinical studies also suggest that combined CXCL8 blockade and ICIs therapy can enhance the anti-tumor efficacy, and several clinical trials are being conducted to evaluate this therapy modality.

Colorectal liver metastasis: molecular mechanism and interventional therapy

Colorectal cancer (CRC) is one of the most frequently occurring malignancy tumors with a high morbidity additionally, CRC patients may develop liver metastasis, which is the major cause of death. Despite significant advances in diagnostic and therapeutic techniques, the survival rate of colorectal liver metastasis (CRLM) patients remains very low. CRLM, as a complex cascade reaction process involving multiple factors and procedures, has complex and diverse molecular mechanisms. In this review, we summarize the mechanisms/pathophysiology, diagnosis, treatment of CRLM. We also focus on an overview of the recent advances in understanding the molecular basis of CRLM with a special emphasis on tumor microenvironment and promise of newer targeted therapies for CRLM, further improving the prognosis of CRLM patients.

Phosphatases of regenerating liver are key regulators of metabolism in cancer cells - role of Serine/Glycine metabolism

PURPOSE OF REVIEW

Phosphatases of regenerating liver (PRL) are dual-specificity phosphatases and comprise three members, PRL-1, -2 and -3. Despite the importance of PRLs as oncoproteins, there is no consensus function for this family of phosphatases. In the current review paper, we summarize recent findings on the role of PRLs in metabolic regulation.

RECENT FINDINGS

Reprogramming of cellular metabolism is a cancer hallmark. Glucose is the major source of energy in cells. Glucose metabolism occurs through the glycolysis and can continue through the pathways such as serine synthesis pathway or the tricarboxylic acid cycle (TCA). Magnesium (Mg2+), the second most abundant cation in cells, plays an essential role in energy production by acting as a cofactor for most enzymes involved in glycolysis and in TCA. Recent findings have shown that the PRL family has a role in metabolic reprogramming mediated by (1) Mg2+ homeostasis, (2) shifting the energy source preference to glucose consumption and fueling serine/glycine pathway and (3) regulating PI3 kinase/Mammalian target of rapamycin complex. Both the phosphatase and nonphosphatase activity of PRLs appear to be important for its oncogenic role.

SUMMARY

The PRL family contributes to the metabolic plasticity of cancer cells and, thereby, allows cancer cells to meet the high metabolic demands required for cell proliferation.

Phosphatase of regenerating liver-3 regulates cancer cell metabolism in multiple myeloma

Cancer cells often depend on microenvironment signals from molecules such as cytokines for proliferation and metabolic adaptations. PRL-3, a cytokine-induced oncogenic phosphatase, is highly expressed in multiple myeloma cells and associated with poor outcome in this cancer. We studied whether PRL-3 influences metabolism. Cells transduced to express PRL-3 had higher aerobic glycolytic rate, oxidative phosphorylation, and ATP production than the control cells. PRL-3 promoted glucose uptake and lactate excretion, enhanced the levels of proteins regulating glycolysis and enzymes in the serine/glycine synthesis pathway, a side branch of glycolysis. Moreover, mRNAs for these proteins correlated with PRL-3 expression in primary patient myeloma cells. Glycine decarboxylase (GLDC) was the most significantly induced metabolism gene. Forced GLDC downregulation partly counteracted PRL-3-induced aerobic glycolysis, indicating GLDC involvement in a PRL-3-driven Warburg effect. AMPK, HIF-1α, and c-Myc, important metabolic regulators in cancer cells, were not mediators of PRL-3's metabolic effects. A phosphatase-dead PRL-3 mutant, C104S, promoted many of the metabolic changes induced by wild-type PRL-3, arguing that important metabolic effects of PRL-3 are independent of its phosphatase activity. Through this study, PRL-3 emerges as one of the key mediators of metabolic adaptations in multiple myeloma.

Protein Tyrosine Phosphatases: A new paradigm in an old signaling system?

Protein Tyrosine Phosphatases reverse cellular signals initiated by growth factors receptors and other tyrosine kinases by dephosphorylating phosphotyrosine on target proteins. The activity of these enzymes is crucial for maintaining cell homeostasis, yet these enzymes have been often dismissed as humble house-keeping proteins. Understandably, mutations and changes in expression patterns of Protein Tyrosine Phosphatases are implicated in tumorigenesis and various carcinomas. The conserved nature of their catalytic domains makes drug discovery a challenging pursuit. In this review, we focus on describing the various classes of Protein Tyrosine Phosphatases and their catalytic domains. We also summarize their role in cancer and neurodegenerative diseases using specific members as the model system. Finally, we explain the dichotomy in the biological role of catalytically active vs the pseudoenzyme forms of Protein Tyrosine Phosphatases in the context of their membrane bound receptor forms. This chapter aims to provide a current understanding of these proteins, in the background of their foundational past research.

Hypoxia-induced CNPY2 upregulation promotes glycolysis in cervical cancer through activation of AKT pathway

This study aimed to investigate the function and mechanism of the protein-coding gene CNPY2 in the glycolysis of cervical cancer cells. Cells were exposed to normoxia and hypoxia conditions. Knockdown and ectopic overexpression of CNPY2 were achieved by transfection of small interfering RNA (siRNA) specific to CNPY2 or CNPY2 overexpression vectors, respectively. Quantitative real-time PCR and Western blot were used to evaluate CNPY2 expression in patient specimens and different cervical cancer cell lines under normoxia or hypoxia conditions. Cell viability was assessed by MTT and colony formation assays. Glucose consumption, lactate production, oxygen consumption and ATP production were analyzed by enzyme-linked immunosorbent assays. Dual-luciferase reporter assay and chromatin immunoprecipitation assay were performed to detect interaction between hypoxia-induced factor 1α (HIF-1α) on CNPY2 promoter. CNPY2 upregulation was a characteristic of cervical cancer and correlated with poor prognosis. Knockdown and overexpression of CNPY2 inhibited and promoted proliferation glucose consumption, lactate production, oxygen consumption and ATP production in cervical cancer cells, respectively. CNPY2 was transcriptionally regulated by HIF-1α. The hypoxia-induced "Warburg effect" in cervical cancer cells was at least partially dependent on the CNPY2/AKT signaling pathway. Hypoxia-induced CNPY2 promoted glycolysis in cervical cancer cells by activating the AKT pathway. CNPY2 may serve as a potential diagnostic marker and therapeutic target for cervical cancer patients.

Identification of Five Glycolysis-Related Gene Signature and Risk Score Model for Colorectal Cancer

Metabolic changes, especially in glucose metabolism, are widely established during the occurrence and development of tumors and regarded as biological markers of pan-cancer. The well-known ‘Warburg effect’ demonstrates that cancer cells prefer aerobic glycolysis even if there is sufficient ambient oxygen. Accumulating evidence suggests that aerobic glycolysis plays a pivotal role in colorectal cancer (CRC) development. However, few studies have examined the relationship of glycolytic gene clusters with prognosis of CRC patients. Here, our aim is to build a glycolysis-associated gene signature as a biomarker for colorectal cancer. The mRNA sequencing and corresponding clinical data were downloaded from TCGA and GEO databases. Gene set enrichment analysis (GSEA) was performed, indicating that four gene clusters were significantly enriched, which revealed the inextricable relationship of CRC with glycolysis. By comparing gene expression of cancer and adjacent samples, 236 genes were identified. Univariate, multivariate, and LASSO Cox regression analyses screened out five prognostic-related genes (ENO3, GPC1, P4HA1, SPAG4, and STC2). Kaplan–Meier curves and receiver operating characteristic curves (ROC, AUC = 0.766) showed that the risk model could become an effective prognostic indicator (P < 0.001). Multivariate Cox analysis also revealed that this risk model is independent of age and TNM stages. We further validated this risk model in external cohorts (GES38832 and GSE39582), showing these five glycolytic genes could emerge as reliable predictors for CRC patients’ outcomes. Lastly, based on five genes and risk score, we construct a nomogram model assessed by C-index (0.7905) and calibration plot. In conclusion, we highlighted the clinical significance of glycolysis in CRC and constructed a glycolysis-related prognostic model, providing a promising target for glycolysis regulation in CRC.

A comprehensive review on the role of protein tyrosine phosphatases in gastric cancer development and progression

The main post-translational reversible modulation of proteins is phosphorylation and dephosphorylation, catalyzed by protein kinases (PKs) and protein phosphatases (PPs) which is crucial for homeostasis. Imbalance in this crosstalk can be related to diseases, including cancer. Plenty of evidence indicates that protein tyrosine phosphatases (PTPs) can act as tumor suppressors and tumor promoters. In gastric cancer (GC), there is a lack of understanding of the molecular aspects behind the tumoral onset and progression. Here we describe several members of the PTP family related to gastric carcinogenesis. We discuss the associated molecular mechanisms which support the down or up modulation of different PTPs. We emphasize the Helicobacter pylori (H. pylori) virulence which is in part associated with the activation of PTP receptors. We also explore the involvement of intracellular redox state in response to H. pylori infection. In addition, some PTP members are under influence by genetic mutations, epigenetics mechanisms, and miRNA modulation. The understanding of multiple aspects of PTPs in GC may provide new targets and perspectives on drug development.

LncRNA XIST/miR-137 axis strengthens chemo-resistance and glycolysis of colorectal cancer cells by hindering transformation from PKM2 to PKM1

BACKGROUND

Glycolysis was an essential driver of chemo-resistance in colorectal cancer (CRC), albeit with limited molecular explanations.

OBJECTIVE

We strived to elucidate the involvement of lncRNA XIST/miR-137/PKM axis in chemo-tolerance and glycolysis of CRC.

METHODS

Altogether 212 pairs of tumor tissues and adjacent normal tissues were collected from CRC patients. Moreover, human CRC epithelial cell lines, including HT29, SW480, SW620 and LoVo, were purchased in advance, and their activity was estimated after transfection of si-XIST or miR-137 mimic. Furthermore, 5-FU/cisplatin-resistance of CRC cells was determined through MTT assay, and glycolytic potential of CRC cells was appraised based on oxygen consumption rate (OCR) and extracellular acidification rate (ECAR).

RESULTS

Highly-expressed XIST were predictive of severe symptoms and unfavorable 3-year survival of CRC patients (P< 0.05). Besides, silencing of XIST not only diminished proliferative, migratory and invasive power of CRC cells (P< 0.05), but also enhanced sensitivity of CRC cells responding to 5-FU/cisplatin (P< 0.05). Glycolytic potency of CRC cells was also undermined by si-XIST, with decreased maximal respiration and maximal glycolytic capacity in the si-XIST group as relative to NC group (P< 0.05). Nevertheless, miR-137 mimic attenuated the facilitating effect of pcDNA3.1-XIST on proliferation, migration, invasion, 5-FU/cisplatin-resistance and glycolysis of CRC cells (P< 0.05). Ultimately, ratio of PKM2 mRNA and PKM1 mRNA, despite being up-regulated by pcDNA3.1-XIST, was markedly lowered when miR-137 mimic was co-transfected (P< 0.05).

CONCLUSIONS

LncRNA XIST/miR-137 axis reinforced glycolysis and chemo-tolerance of CRC by elevating PKM2/PKM1 ratio, providing an alternative to boost chemo-therapeutic efficacy of CRC patients.

Platelet isoform of phosphofructokinase promotes aerobic glycolysis and the progression of non‑small cell lung cancer

The platelet isoform of phosphofructokinase (PFKP) is a rate-limiting enzyme involved in glycolysis that serves an important role in various types of cancer. The aim of the present study was to explore the specific regulatory relationship between PFKP and non-small cell lung cancer (NSCLC) progression. PFKP expression in NSCLC tissues and corresponding adjacent tissues was detected using reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and immunohistochemical analysis. PFKP expression in human bronchial epithelial cells (16HBE) and NSCLC cells (H1299, H23 and A549) was also detected using RT-qPCR. Cell proliferation was detected by Cell Counting Kit-8 and colony formation assays. Transwell invasion and wound healing assays, and flow cytometry were used to detect cell invasion, migration and apoptosis, respectively. The expression levels of glycolysis-associated enzymes (hexokinase-2, lactate dehydrogenase A and glucose transporter-1), epithelial-mesenchymal transition-related proteins (N-cadherin, vimentin and E-cadherin) and apoptosis-related proteins (caspase-3 and B-cell lymphoma-2) were detected by western blotting. Glucose uptake, lactate production and the adenosine trisphosphate/adenosine diphosphate ratio were measured using the corresponding kits. The results of the present study demonstrated that PFKP expression was upregulated in NSCLC tissues and cells, and PFKP expression was related to lymph node metastasis and histological grade. In addition, overexpression of PFKP inhibited cell apoptosis, and promoted proliferation, migration, invasion and glycolysis of H1299 cells, whereas knockdown of PFKP had the opposite effects. In conclusion, PFKP inhibited cell apoptosis, and promoted proliferation, migration, invasion and glycolysis of NSCLC cells; these findings may lay the foundation for novel treatments of NSCLC.

Elevated Sad1 and UNC84 Domain Containing 2 (SUN2) level inhibits cell growth and aerobic glycolysis in oral cancer through reducing the expressions of glucose transporter 1 (GLUT1) and lactate dehydrogenase A (LDHA)

Background/purpose

Oral cancer is a malignant tumor accompanied by high morbidity, mortality, and poor prognosis. Therefore, it is urgent to explore the percise regulation mechanisms underlying oral cancer. Sad1 and UNC84 Domain Containing 2 (SUN2) was considered as a tumor suppressor in some cancers. The purpose of the study was to define the role of SUN2 in oral cancer progression.

Materials and methods

Tumor tissues and paired paracancerous healthy tissues from 56 oral cancer patients were collected. Cell viability was measured using MTT assay. The colony formation assay was applied to determine cell proliferation ability. The mRNA and protein levels were assessed by qRT-PCR and Western blot, respectively.

Results

SUN2 expression was decreased in oral cancer tissues and cell models. SUN2 overexpression suppressed the growth of oral cancer cells, while the down-regulation of SUN2 promoted cell growth. SUN2 overexpression restrained the glucose uptake, lactate production, and ATP level of oral cancer cells, whereas down-regulation of SUN2 promoted glycolysis. Besides, elevated SUN2 inhibited the glucose transporter 1 (GLUT1) and lactate dehydrogenase A (LDHA) levels. However, SUN2 knockdown increased the levels of GLUT1 and LDHA.

Conclusion

SUN2 was decreased in oral cancer in vivo and in vitro. SUN2 overexpression suppressed cell growth and glycolysis via reducing the levels of GLUT1 and LDHA in oral cancer.

IL-8 mediates a positive loop connecting increased neutrophil extracellular traps (NETs) and colorectal cancer liver metastasis

Host and tumorous inflammation actively affect liver metastasis of colorectal cancer (CRC). Neutrophils have been recognized as one active participant in metastasis procedure, with controversial roles however. Activated neutrophils release extracellular traps (NETs) which are involved in infection and multiple pathological conditions. NETs on cancer metastasis is getting recognized but less elucidated in mechanism. How NETs interact with cancer cells is still largely unknown. In this study, we found that neutrophils from CRC patients, especially those with liver metastatic, underwent remarkably enhanced NETs. Clinically, sera and pathological NETs marker closely correlated with onset of liver metastasis. Through in vivo and in vitro studies, we proved that increased NETs positively contribute to onset of CRC liver metastasis. Digesting NETs with DNase 1 diminished the increased liver metastasis associated with NETs. In detail, NETs trapped CRC cells in liver and exerted no cytotoxicity on tumor cells, but boosted tumorous proliferation and invasion capacity. We further found this enhanced malignancy of trapped CRC cells was due to the elevated tumorous interleukin (IL)-8 expression triggered by NETs. Blocking IL-8 activity effectively abrogated the enhanced proliferation and invasion triggered by NETs. Moreover, overproduced IL-8 in turn activate neutrophils towards NETs formation, thus forming a positive loop optimizing CRC liver metastasis. Collectively, our study propose a novel positive feedback between elevated tumorous IL-8 and NETs to promote CRC liver metastasis, and identify potential strategy against liver metastasis.

PTP4A3, A Novel Target Gene of HIF-1alpha, Participates in Benzene-Induced Cell Proliferation Inhibition and Apoptosis through PI3K/AKT Pathway

Benzene, a commonly used chemical, has been confirmed to specifically affect the hematopoietic system as well as overall human health. PTP4A3 is overexpressed in leukemia cells and is related to cell proliferation. We previously found that HIF-1alpha was involved in benzene toxicity and PTP4A3 may be the target gene of HIF-1alpha via ChIP-seq. The aim of this study is to confirm the relationship between HIF-1alpha and PTP4A3 in benzene toxicity, as well as the function of PTP4A3 on cell toxicity induced by 1,4-benzoquinone (1,4-BQ). Our results indicate that HIF-1alpha could regulate PTP4A3 with in vivo and in vitro experiments. A cell line with suppressed PTP4A3 was established to investigate the function of PTP4A3 in 1,4-BQ toxicity in vitro. The results revealed that cell proliferation inhibition was more aggravated in PTP4A3 low-expression cells than in the control cells after 1,4-BQ treatment. The relative oxygen species (ROS) significantly increased in cells with inhibited PTP4A3, while the rise was inferior to the control cells at the 20 μM 1,4-BQ group. An increase in DNA damage was seen in PTP4A3 down-regulated cells at the 10 μM 1,4-BQ group, whereas the results reversed at the concentration of 20 μM. Moreover, the apoptosis rate increased higher in down-regulated PTP4A3 cells after 1,4-BQ exposure. In addition, PI3K/AKT pathway was significantly restrained in cells with inhibited PTP4A3 after 1,4-BQ treatment. Our results indicate that HIF-1alpha may regulate PTP4A3 to be involved in benzene toxicity. Inhibition of PTP4A3 could aggravate cell proliferation suppression and apoptosis by regulating PI3K/AKT pathway after 1,4-BQ treatment.

Long non-coding RNA MALAT1 facilitates the tumorigenesis, invasion and glycolysis of multiple myeloma via miR-1271-5p/SOX13 axis

Background

Long non-coding RNAs (lncRNAs) play crucial roles in the regulation and treatment of multiple myeloma (MM). The objective of this research was to study the functional mechanism of metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) in MM.

Methods

MALAT1, microRNA-1271-5p (miR-1271-5p), and SRY-Box 13 (SOX13) levels were examined by quantitative real-time polymerase chain reaction (qRT-PCR). Cell viability, apoptosis, and invasion were respectively assayed using 3-(4, 5-dimethylthiazol-2-y1)-2, 5-diphenyl tetrazolium bromide (MTT), flow cytometry, and transwell assay. Glycolysis was evaluated by glucose consumption, lactate production, ATP/ADP ratio, and the detection of related enzymes. Associated proteins were measured using Western blot. Target relation was verified via dual-luciferase reporter assay. Xenograft tumor assay was implemented to study the influence of MALAT1 on MM in vivo.

Results

The up-regulation of MALAT1 and the down-regulation of miR-1271-5p were found in MM serums and cells. MALAT1 knockdown suppressed cell viability, invasion, and glycolysis while expedited cell apoptosis in MM cells. MALAT1 directly targeted miR-1271-5p and miR-1271-5p depression reverted the effects of MALAT1 knockdown on MM cells. SOX13 was a target of miR-1271-5p and SOX13 overexpression weakened the effects of miR-1271-5p on MM. MALAT1 indirectly modulated SOX13 expression through targeting miR-1271-5p. MALAT1 down-regulation inhibited MM growth by miR-1271-5p/SOX13 axis in vivo.

Conclusion

LncRNA MALAT1 expedited MM tumorigenesis, invasion, and glycolysis via miR-1271-5p/SOX13 axis. MALAT1 might contribute to the therapy of MM as a promising indicator.

Up-Regulation of Phosphatase in Regenerating Liver-3 (PRL-3) Contributes to Malignant Progression of Hepatocellular Carcinoma by Activating Phosphatase and Tensin Homolog Deleted on Chromosome Ten (PTEN)/Phosphoinositide 3-Kinase (PI3K)/AKT Signaling Pathway

BACKGROUND The purpose of the study was to investigate the functional roles of phosphatase in regenerating liver-3 (PRL-3) in hepatocellular carcinoma (HCC), as well as the related molecular mechanisms. MATERIAL AND METHODS HCC tissues and adjacent normal tissues were collected from 124 HCC patients. The mRNA and protein levels of PRL-3 were detected using quantitative real-time polymerase chain reaction (qRT-PCR) and Western blot assays, respectively. The relationship between PRL-3 expression and clinical characteristics of HCC patients was evaluated by chi-square test. MTT and Transwell assays were performed to estimate cell proliferation and motility, respectively. RESULTS The expression of PRL-3 was significantly increased in HCC tissues and cells at both protein and mRNA levels (P<0.01 for all). Furthermore, the up-regulation of PRL-3 was positively correlated with hepatic vascular invasion (P=0.019), lymph node metastasis (P=0.012), and TNM stage (P=0.001). The knockdown of PRL-3 suppressed HCC cell proliferation, migration, and invasion, and PR3K/AKT pathway activity was also obviously inhibited in HCC cells with PRL-3 deficiency. The levels of PTEN were negatively associated with PRL-3 expression. PRL-3 might inhibit the protein level of PTEN through enhancing its phosphorylation level. The transfection of si-PTEN can reverse the anti-tumor action caused by PRL-3 knockdown in HCC cells. CONCLUSIONS Up-regulation of PRL-3 may activate the PI3K/AKT signaling pathway and enhance malignant progression of HCC through targeting PTEN.

LncRNA-p23154 promotes the invasion-metastasis potential of oral squamous cell carcinoma by regulating Glut1-mediated glycolysis

The dysregulation of glycolysis has been suggested to lead to alteration of cell drug resistance signals, proliferation and metastasis. Emerging evidence indicates that lncRNAs play a key role in the cellular processes of tumor cells, including glycolysis, growth, and movement. However, the role and potential mechanism of lncRNAs in glycolysis-mediated metastasis has not been explored. In this study, we identified a novel lncRNA lnc-p23154 which is associated with OSCC patient metastasis and the promotion of OSCC cell migration and invasion in vitro and in vivo. Furthermore, we found that lnc-p23154 also participates in OSCC glycolysis by facilitating Glut1 expression. Rescue of lnc-p23154 reversed the suppression of OSCC cell migration and invasion induced by Glut1 knockdown. In addition, lnc-p23154 is mainly located in the nucleus and binds to the promoter region of miR-378a-3p, which represses Glut1 expression by targeting to its 3'UTR directly. Therefore, we concluded that lnc-p23154 may play an important role in Glut1-mediated glycolysis by inhibiting miR-378a-3p transcription and accelerate OSCC metastasis.

PRL‑3 increases the aggressive phenotype of prostate cancer cells in vitro and its expression correlates with high-grade prostate tumors in patients

The increased expression of phosphatase of regenerating liver-3 (PRL-3) has been shown to be associated with the aggressive and metastatic phenotype of different solid tumors. However, it is not known whether PRL-3 plays a similar role in the progression of prostate cancer (PCa). In this study, immunoblot analysis of androgen receptor (AR)-positive PCa lines (LNCaP and LNCaP-SF) revealed the constitutive cytoplasmic expression of PRL-3, and stimulation with R1881 (AR agonist) rapidly increased the nuclear translocation of PRL-3. The AR-negative cell lines exhibited negligible PRL-3 expression, and the ectopic overexpression of PRL-3 increased both the proliferative and invasive potential of PC3 and DU145 cells. In addition, we measured PRL-3 protein expression in human prostate tumor sections. A high-density prostate tumor microarray (TMA) was immunostained to assess whether PRL-3 expression and its subcellular localization (cytoplasmic and nuclear levels) is associated with the Gleason score (GS), Gleason grade (GG) and tumor stage (T-stage). Digital image analysis (DIA) revealed that PRL-3 expression was significantly higher in the malignant cores, as compared to the non-malignant areas. Increases in both total and nuclear PRL-3 levels were also associated with a higher GS and GG. Metastatic tumors (T4-stage) had lower cytoplasmic, but higher nuclear PRL-3 levels. Furthermore, the nuclear/cytoplasmic ratio for PRL-3 in the tumors graded as GS7 could effectively distinguish between indolent (3+4) and aggressive (4+3) disease. Thus, our experiments using PCa lines suggested that PRL-3 is an AR-regulated gene and its androgen-induced nuclear localization may increase the aggressive behavior of PCa cells. Furthermore, the digital analysis of immunostained tumor sections suggested that PRL-3 may be an effective biomarker of high-grade PCa, and its nuclear/cytoplasmic ratio may be used to distinguish between indolent vs. aggressive tumors.