PTEN regulates plasma membrane expression of glucose transporter 1 and glucose uptake in thyroid cancer cells

Advances in traditional herbal formulation based nano-vaccine for cancer immunotherapy: Unraveling the enigma of complex tumor environment and multidrug resistance

Cancer is attributed to uncontrolled cell growth and is among the leading causes of death with no known effective treatment while complex tumor microenvironment (TME) and multidrug resistance (MDR) are major challenges for developing an effective therapeutic strategy. Advancement in cancer immunotherapy has been limited by the over-activation of the host immune response that ultimately affects healthy tissues or organs and leads to a feeble response of the patient's immune system against tumor cells. Besides, traditional herbal medicines (THM) have been well-known for their essential role in the treatment of cancer and are considered relatively safe due to their compatibility with the human body. Yet, poor solubility, low bio-availability, and lack of understanding about their pathophysiological mechanism halt their clinical application. Moreover, considering the complex TME and drug resistance, the most precarious and least discussed concerns for developing THM-based nano-vaccination, are identification of specific biomarkers for drug inhibitory protein and targeted delivery of bioactive ingredients of THM on the specific sites in tumor cells. The concept of THM-based nano-vaccination indicates immunomodulation of TME by THM-based bioactive adjuvants, exerting immunomodulatory effects, via targeted inhibition of key proteins involved in the metastasis of cancer. However, this concept is at its nascent stage and very few preclinical studies provided the evidence to support clinical translation. Therefore, we attempted to capsulize previously reported studies highlighting the role of THM-based nano-medicine in reducing the risk of MDR and combating complex tumor environments to provide a reference for future study design by discussing the challenges and opportunities for developing an effective and safe therapeutic strategy against cancer.

Exploring the clinical utility of DPP-IV and SGLT2 inhibitors in papillary thyroid cancer: a literature review

In the realm of clinical management, Papillary Thyroid Cancer (PTC) stands out as a prevalent thyroid malignancy, characterized by significant metabolic challenges, particularly in the context of carbohydrate metabolism. Recent studies have unveiled promising applications of Dipeptidyl Peptidase-IV (DPP-IV) and Sodium-Glucose Cotransporter 2 (SGLT2) inhibitors, which are conventionally employed in the treatment of type 2 diabetes mellitus (T2DM), as potential adjuncts in anticancer therapy. DPP-IV and SGLT2 inhibitors can be imply to counteract the Warburg effect in cancer, with a specific focus on PTC, owing to their potential metabolic advantages and their influence on the tumor microenvironment, achieved by imposing restrictions on glucose accessibility. Consequently, a comprehensive review has been undertaken, involving meticulous examination of the existing body of evidence pertaining to the utilization of DPP-IV and SGLT2 inhibitors in the context of PTC. The mechanisms of action inherent to these inhibitors have been thoroughly explored, drawing upon insights derived from preclinical investigations. Furthermore, this review initiates discussions concerning the implications for future research directions and the formulation of innovative therapeutic strategies for PTC. As the intricate interplay between carbohydrate metabolism, the Warburg effect, and cancer progression garners increasing attention, attaining a comprehensive understanding of the roles played by DPP-IV and SGLT2 inhibitors in PTC management may serve as the cornerstone for novel approaches aimed at enhancing patient care and broadening the spectrum of available therapeutic modalities.

Synthetic lethal approaches to target cancers with loss of PTEN function

Phosphatase and tensin homolog (PTEN) is a tumour suppressor gene and has a role in inhibiting the oncogenic AKT signalling pathway by dephosphorylating phosphatidylinositol 3,4,5-triphosphate (PIP3) into phosphatidylinositol 4,5-bisphosphate (PIP2). The function of PTEN is regulated by different mechanisms and inactive PTEN results in aggressive tumour phenotype and tumorigenesis. Identifying targeted therapies for inactive tumour suppressor genes such as PTEN has been challenging as it is difficult to restore the tumour suppressor functions. Therefore, focusing on the downstream signalling pathways to discover a targeted therapy for inactive tumour suppressor genes has highlighted the importance of synthetic lethality studies. This review focuses on the potential synthetic lethality genes discovered in PTEN-inactive cancer types. These discovered genes could be potential targeted therapies for PTEN-inactive cancer types and may improve the treatment response rates for aggressive types of cancer.

Metabolic Deregulation in Pulmonary Hypertension

The high morbidity and mortality rate of pulmonary arterial hypertension (PAH) is partially explained by metabolic deregulation. The present study complements our previous publication in "Genes" by identifying significant increases of the glucose transporter solute carrier family 2 (Slc2a1), beta nerve growth factor (Ngf), and nuclear factor erythroid-derived 2-like 2 (Nfe2l2) in three standard PAH rat models. PAH was induced by subjecting the animals to hypoxia (HO), or by injecting with monocrotaline in either normal (CM) or hypoxic (HM) atmospheric conditions. The Western blot and double immunofluorescent experiments were complemented with novel analyses of previously published transcriptomic datasets of the animal lungs from the perspective of the Genomic Fabric Paradigm. We found substantial remodeling of the citrate cycle, pyruvate metabolism, glycolysis/gluconeogenesis, and fructose and mannose pathways. According to the transcriptomic distance, glycolysis/gluconeogenesis was the most affected functional pathway in all three PAH models. PAH decoupled the coordinated expression of many metabolic genes, and replaced phosphomannomutase 2 (Pmm2) with phosphomannomutase 1 (Pmm1) in the center of the fructose and mannose metabolism. We also found significant regulation of key genes involved in PAH channelopathies. In conclusion, our data show that metabolic dysregulation is a major PAH pathogenic factor.

Deregulated Metabolic Pathways in Ovarian Cancer: Cause and Consequence

Ovarian cancers are tumors that originate from the different cells of the ovary and account for almost 4% of all the cancers in women globally. More than 30 types of tumors have been identified based on the cellular origins. Epithelial ovarian cancer (EOC) is the most common and lethal type of ovarian cancer which can be further divided into high-grade serous, low-grade serous, endometrioid, clear cell, and mucinous carcinoma. Ovarian carcinogenesis has been long attributed to endometriosis which is a chronic inflammation of the reproductive tract leading to progressive accumulation of mutations. Due to the advent of multi-omics datasets, the consequences of somatic mutations and their role in altered tumor metabolism has been well elucidated. Several oncogenes and tumor suppressor genes have been implicated in the progression of ovarian cancer. In this review, we highlight the genetic alterations undergone by the key oncogenes and tumor suppressor genes responsible for the development of ovarian cancer. We also summarize the role of these oncogenes and tumor suppressor genes and their association with a deregulated network of fatty acid, glycolysis, tricarboxylic acid and amino acid metabolism in ovarian cancers. Identification of genomic and metabolic circuits will be useful in clinical stratification of patients with complex etiologies and in identifying drug targets for personalized therapies against cancer.

Reprogramming of Cellular Metabolism and Its Therapeutic Applications in Thyroid Cancer

Metabolism is a series of life-sustaining chemical reactions in organisms, providing energy required for cellular processes and building blocks for cellular constituents of proteins, lipids, carbohydrates and nucleic acids. Cancer cells frequently reprogram their metabolic behaviors to adapt their rapid proliferation and altered tumor microenvironments. Not only aerobic glycolysis (also termed the Warburg effect) but also altered mitochondrial metabolism, amino acid metabolism and lipid metabolism play important roles for cancer growth and aggressiveness. Thus, the mechanistic elucidation of these metabolic changes is invaluable for understanding the pathogenesis of cancers and developing novel metabolism-targeted therapies. In this review article, we first provide an overview of essential metabolic mechanisms, and then summarize the recent findings of metabolic reprogramming and the recent reports of metabolism-targeted therapies for thyroid cancer.

Double Deletion of PI3K and PTEN Modifies Lens Postnatal Growth and Homeostasis

We have previously shown that the conditional deletion of either the p110α catalytic subunit of phosphatidylinositol 3-kinase (PI3K), or its opposing phosphatase, phosphatase and tensin homolog (PTEN), had distinct effects on lens growth and homeostasis. The deletion of p110α reduced the levels of phosphorylated Akt and equatorial epithelial cell proliferation, and resulted in smaller transparent lenses in adult mice. The deletion of PTEN increased levels of phosphorylated Akt, altered lens sodium transport, and caused lens rupture and cataract. Here, we have generated conditional p110α/PTEN double-knockout mice, and evaluated epithelial cell proliferation and lens homeostasis. The double deletion of p110α and PTEN rescued the defect in lens size seen after the single knockout of p110α, but accelerated the lens rupture phenotype seen in PTEN single-knockout mice. Levels of phosphorylated Akt in double-knockout lenses were significantly higher than in wild-type lenses, but not as elevated as those reported for PTEN single-knockout lenses. These results showed that the double deletion of the p110α catalytic subunit of PI3K and its opposing phosphatase, PTEN, exacerbated the rupture defect seen in the single PTEN knockout and alleviated the growth defect observed in the single p110α knockout. Thus, the integrity of the PI3K signaling pathway was absolutely essential for proper lens homeostasis, but not for lens growth.

GLUT1 and ASCT2 Protein Expression in Papillary Thyroid Carcinoma Patients and Relation to Hepatitis C Virus: A Propensity-Score Matched Analysis

Purpose

Recently, glucose and amino acid transporters have gradually become a hot topic in thyroid gland biology and cancer research. We aimed to investigate the expressions of glucose transporter 1 (GLUT1) and glutamine transporter 2 (ASCT2) in papillary thyroid carcinoma (PTC) and their clinical significance and relation to HCV-related hepatitis.

Patients and Methods

Screening 202 TC tissue samples against the selection criteria using a propensity-score matched analysis to adjust for age, sex, side of tumor, histopathological variants, TNM staging system, and the positivity for HCV yielded 51 matched (17 HCV positive and 34 HCV negative) PTC samples. The expressions of GLUT1 and ASCT2 expressions were detected by immunohistochemical staining. Kaplan–Meier survival curves were generated for disease-free and overall survival, and multivariate Cox regression analysis was applied to identify predictors for mortality.

Results

Of 51 thyroid cancer tissues, 85% showed positive GLUT1 cytoplasmic staining, and 26% had a high expression score. All thyroid cancer specimens demonstrated ASCT2 cytoplasmic staining with membranous accentuation. Of these, 78% showed a high expression score, and 22% showed weak staining. On stratifying the study cohort based on the HCV status, HCV negative cohort showed a significantly higher immunoreactivity score for GLUT1 (p = 0.004) but not ASCT2 (p = 0.94) than HCV positive group. The expressions of the studied transporters showed no significant associations with the prognostic features of PTC nor the disease-free/overall survival.

Conclusion

GLUT1 and ASCT2 immunohistochemical staining showed positive expression with variable intensity in nearly 85% and 100% of PTC tissue samples compared to normal ones, respectively. Furthermore, GLUT1 protein expression, not ASCT2, showed a higher immunoreactivity score in PTC patients who are negative for HCV than cancer patients with positive HCV. Meanwhile, the expression of both protein markers was not associated with the clinicopathological characteristics of the studied PTC patients. Further large-scale multicenter studies are recommended to validate the present findings.

Metabolic reprogramming by traditional Chinese medicine and its role in effective cancer therapy

Metabolic reprogramming, characterized by alterations of cellular metabolic patterns, is fundamentally important in supporting the malignant behaviors of cancer cells. It is considered as a promising therapeutic target against cancer. Traditional Chinese medicine (TCM) and its bioactive components have been used in cancer therapy for an extended period, and they are well-known for their multi-target pharmacological functions and fewer side effects. However, the detailed and advanced mechanisms underlying the anticancer activities of TCM remain obscure. In this review, we summarized the critical processes of cancer cell metabolic reprogramming, including glycolysis, mitochondrial oxidative phosphorylation, glutaminolysis, and fatty acid biosynthesis. Moreover, we systemically reviewed the regulatory effects of TCM and its bioactive ingredients on metabolic enzymes and/or signal pathways that may impede cancer progress. A total of 46 kinds of TCMs was reported to exert antitumor effects and/or act as chemosensitizers via regulating metabolic processes of cancer cells, and multiple targets and signaling pathways were revealed to contribute to the metabolic-modulating functions of TCM. In conclusion, TCM has its advantages in ameliorating cancer cell metabolic reprogramming by its poly-pharmacological actions. This review may shed some new light on the explicit recognition of the mechanisms of anticancer actions of TCM, leading to the development of natural antitumor drugs based on reshaping cancer cell metabolism.

Metabolic reprogramming in renal cancer: Events of a metabolic disease

Recent studies have established that tumors can reprogram the pathways involved in nutrient uptake and metabolism to withstand the altered biosynthetic, bioenergetics and redox requirements of cancer cells. This phenomenon is called metabolic reprogramming, which is promoted by the loss of tumor suppressor genes and activation of oncogenes. Because of alterations and perturbations in multiple metabolic pathways, renal cell carcinoma (RCC) is sometimes termed as a "metabolic disease". The majority of metabolic reprogramming in renal cancer is caused by the inactivation of von Hippel-Lindau (VHL) gene and activation of the Ras-PI3K-AKT-mTOR pathway. Hypoxia-inducible factor (HIF) and Myc are other important players in the metabolic reprogramming of RCC. All types of RCCs are associated with reprogramming of glucose and fatty acid metabolism and the tricarboxylic acid (TCA) cycle. Metabolism of glutamine, tryptophan and arginine is also reprogrammed in renal cancer to favor tumor growth and oncogenesis. Together, understanding these modifications or reprogramming of the metabolic pathways in detail offer ample opportunities for the development of new therapeutic targets and strategies, discovery of biomarkers and identification of effective tumor detection methods.

POU2F2 regulates glycolytic reprogramming and glioblastoma progression via PDPK1-dependent activation of PI3K/AKT/mTOR pathway

The POU Class Homeobox 2 (POU2F2) is a member of POU transcription factors family, which involves in cell immune response by regulating B cell proliferation and differentiation genes. Recent studies have shown that POU2F2 acts as tumor-promoting roles in some cancers, but the underlying mechanism remains little known. Here, we identified that the highly expressed POU2F2 significantly correlated with poor prognosis of glioblastoma (GBM) patients. POU2F2 promoted cell proliferation and regulated glycolytic reprogramming. Mechanistically, the AKT/mTOR signaling pathway played important roles in the regulation of POU2F2-mediated aerobic glycolysis and cell growth. Furthermore, we demonstrated that POU2F2 activated the transcription of PDPK1 by directly binding to its promoter. Reconstituted the expression of PDPK1 in POU2F2-knockdown GBM cells reactivated AKT/mTOR pathway and recovered cell glycolysis and proliferation, whereas this effect was abolished by the PDPK1/AKT interaction inhibitor. In addition, we showed that POU2F2-PDPK1 axis promoted tumorigenesis by regulating glycolysis in vivo. In conclusion, our findings indicate that POU2F2 leads a metabolic shift towards aerobic glycolysis and promotes GBM progression in PDPK1-dependent activation of PI3K/AKT/mTOR pathway.

Physiological and Pathophysiological Roles of Ion Transporter-Mediated Metabolism in the Thyroid Gland and in Thyroid Cancer

Thyroid cancer is the most common type of endocrine tumor and has shown an increasing annual incidence, especially among women. Patients with thyroid cancer have a good prognosis, with a high five-year survival rate; however, the recurrence rate and disease status of thyroid cancer remain a burden for patients, which compels us to further elucidate the pathogenesis of this disease. Recently, ion transporters have gradually become a hot topic in the field of thyroid gland biology and cancer research. Additionally, alterations in the metabolic state of tumor cells and protein molecules have gradually become the focus of scientific research. This review focuses on the progress in understanding the physiological and pathophysiological roles of ion transporter-mediated metabolism in both the thyroid gland and thyroid cancer. We also hope to shed light on new targets for the treatment and prognosis of thyroid cancer.

Cytochrome C Oxidase Subunit 4 (COX4): A Potential Therapeutic Target for the Treatment of Medullary Thyroid Cancer

The nuclear-encoded subunit 4 of cytochrome c oxidase (COX4) plays a role in regulation of oxidative phosphorylation and contributes to cancer progression. We sought to determine the role of COX4 in differentiated (DTC) and medullary (MTC) thyroid cancers. We examined the expression of COX4 in human thyroid tumors by immunostaining and used shRNA-mediated knockdown of COX4 to evaluate its functional contributions in thyroid cancer cell lines. In human thyroid tissue, the expression of COX4 was higher in cancers than in either normal thyroid (p = 0.0001) or adenomas (p = 0.001). The level of COX4 expression correlated with tumor size (p = 0.04) and lymph-node metastases (p = 0.024) in patients with MTCs. COX4 silencing had no effects on cell signaling activation and mitochondrial respiration in DTC cell lines (FTC133 and BCPAP). In MTC-derived TT cells, COX4 silencing inhibited p70S6K/pS6 and p-ERK signaling, and was associated with decreased oxygen consumption and ATP production. Treatment with potassium cyanide had minimal effects on FTC133 and BCPAP, but inhibited mitochondrial respiration and induced apoptosis in MTC-derived TT cells. Our data demonstrated that metastatic MTCs are characterized by increased expression of COX4, and MTC-derived TT cells are vulnerable to COX4 silencing. These data suggest that COX4 can be considered as a novel molecular target for the treatment of MTC.

Gout and pseudo-gout-related crystals promote GLUT1-mediated glycolysis that governs NLRP3 and interleukin-1β activation on macrophages

OBJECTIVE

Macrophage activation by monosodium urate (MSU) and calcium pyrophosphate (CPP) crystals mediates an interleukin (IL)-1β-dependent inflammation during gout and pseudo-gout flare, respectively. Since metabolic reprogramming of macrophages goes along with inflammatory responses dependently on stimuli and tissue environment, we aimed to decipher the role of glycolysis and oxidative phosphorylation in the IL-1β-induced microcrystal response.

METHODS

Briefly, an in vitro study (metabolomics and real-time extracellular flux analysis) on MSU and CPP crystal-stimulated macrophages was performed to demonstrate the metabolic phenotype of macrophages. Then, the role of aerobic glycolysis in IL-1β production was evaluated, as well in vitro as in vivo using ¹⁸F-fluorodeoxyglucose positron emission tomography imaging and glucose uptake assay, and molecular approach of glucose transporter 1 (GLUT1) inhibition.

RESULTS

We observed that MSU and CPP crystals led to a metabolic rewiring toward the aerobic glycolysis pathway explained by an increase in GLUT1 plasma membrane expression and glucose uptake on macrophages. Also, neutrophils isolated from human synovial fluid during gout flare expressed GLUT1 at their plasma membrane more frequently than neutrophils isolated from bloodstream. Both glucose deprivation and treatment with either 2-deoxyglucose or GLUT1 inhibitor suppressed crystal-induced NLRP3 activation and IL-1β production, and microcrystal inflammation in vivo.

CONCLUSION

In conclusion, we demonstrated that GLUT1-mediated glucose uptake is instrumental during the inflammatory IL-1β response induced by MSU and CPP crystals. These findings open new therapeutic paths to modulate crystal-related inflammation.

Regulators of glucose uptake in thyroid cancer cell lines

Abstract

Thyroid cancer is the most common sort of endocrine-related cancer with more prevalent in women and elderly individuals which has quickly widespread expansion in worldwide over the recent decades. Common features of malignant thyroid cells are to have accelerated metabolism and increased glucose uptake to optimize their energy supply which provides a fundamental advantage for growth. In tumor cells the retaining of required energy charge for cell survival is imperative, indeed glucose transporters are enable of promoting of this task. According to this relation it has been reported the upregulation of glucose transporters in various types of cancers. Human studies indicated that poor survival can be occurred following the high levels of GLUT1 expression in tumors. GLUT-1 and GLUT3 are the glucose transporters which seems to be mainly engaged with the oncogenesis of thyroid cancer and their expression in malignant tissues is much more than in the normal one. They are promising targets for the advancement of anticancer strategies. The lack of oncosuppressors have dominant effect on the membrane expression of GLUT1 and glucose uptake. Overexpression of hypoxia inducible factors have been additionally connected with distant metastasis in thyroid cancers which mediates transcriptional regulation of glycolytic genes including GLUT1 and GLUT3. Though the physiological role of the thyroid gland is well illustrated, but the metabolic regulations in thyroid cancer remain evasive. In this study we discuss proliferation pathways of the key regulators and signaling molecules such as PI3K-Akt, HIF-1, MicroRNA, PTEN, AMPK, BRAF, c-Myc, TSH, Iodide and p53 which includes in the regulation of GLUTs in thyroid cancer cells. Incidence of deregulations in cellular energetics and metabolism are the most serious signs of cancers. In conclusion, understanding the mechanisms of glucose transportation in normal and pathologic thyroid tissues is critically important and could provide significant insights in science of diagnosis and treatment of thyroid disease.

The Role of the LY294002 - A Non-Selective Inhibitor of Phosphatidylinositol 3-Kinase (PI3K) Pathway- in Cell Survival and Proliferation in Cell Line SCC-25

The activation of PI3K further activates subsequent regulatory pathways, which are activated via AKT phosphorylation. AKT is closely related to the Bcl-2 family, a protein known to be involved in cell survival. AKT also has a relationship with inflammatory and glycolytic mediators. The present work aimed to evaluate the relationship between the PI3K/AKT pathway, cell survival/proliferation, inflammatory mediators and the glycolytic pathway in oral squamous cell carcinoma. All experiments were performed in the SCC25 oral squamous cell carcinoma cell line. In the presence or absence of PI3K pathway inhibitors, we analyzed the protein expression of pAKT and AKT; X-linked inhibitor of apoptosis protein; Bcl-2-associated death promoter; Bcl-2-like protein two inhibitor; cyclooxygenase 1; cyclooxygenase-2; and glycoprotein-associated glucose transporter 1. For the functional characterization of treated or untreated cells, we also performed matrix invasion assays, cell migration assays, and cell proliferation assays. Our results demonstrated that activation of the PI3K/AKT pathway is directly related to members of the Bcl-2 family and GLUT1, but not the inflammatory mediators COX1 and COX2. Our data suggest that the PI3K/AKT pathway is related to cell survival and proliferation in oral squamous cell carcinoma through its interaction with Bcl-2 family members.<br />.

Alteration of transporter activities in the epididymides of infertile initial segment-specific Pten knockout mice

A fully functional initial segment, the most proximal region of the epididymis, is important for male fertility. Our previous study generated a mouse model to investigate the importance of initial segment function in male fertility. In that model, phosphatase and tensin homolog (Pten) was conditionally removed from the initial segment epithelium, which resulted in epithelial de-differentiation. When spermatozoa progressed through the de-differentiated epithelial duct, they developed angled flagella, suggesting compromised sperm maturation, which eventually resulted in male infertility. To understand the molecular mechanisms, by which PTEN regulates epididymal sperm maturation, we compared the transcriptome profile of the initial segment between controls and initial segment-specific Pten knockouts and revealed that water, ion, and organic solute transporter activities were one of the top molecular and cellular functions altered following loss of Pten. Alteration in protein levels and localization of several transporters following loss of Pten were also observed by immunofluorescence analysis. Epithelial cells of the initial segment from knockouts were more permeable to fluorescein isothiocyanate-dextran (4000 Da) compared to controls. Interestingly, conditional deletion of Pten from other organs also resulted in changes in transporter activity, suggesting a common role of PTEN in regulation of transporter activity. Taken together, our data support the hypothesis that loss of Pten from the initial segment epithelium results in changes in the transporting and permeability characteristics of the epithelium, which in turn altered the luminal fluid microenvironment that is so important for sperm maturation and male fertility.

Identification of RNA Expression Profiles in Thyroid Cancer to Construct a Competing Endogenous RNA (ceRNA) Network of mRNAs, Long Noncoding RNAs (lncRNAs), and microRNAs (miRNAs)

Background

The aims of this study were to use RNA expression profile bioinformatics data from cases of thyroid cancer from the Cancer Genome Atlas (TCGA), the Kyoto Encyclopedia of Genes and Genomes (KEGG), and the Gene Ontology (GO) databases to construct a competing endogenous RNA (ceRNA) network of mRNAs, long noncoding RNAs (lncRNAs), and microRNAs (miRNAs).

Material/Methods

TCGA provided RNA profiles from 515 thyroid cancer tissues and 56 normal thyroid tissues. The DESeq R package analyzed high-throughput sequencing data on differentially expressed RNAs. GO and KEGG pathway analysis used the DAVID 6.8 and the ClusterProfile R package. Kaplan-Meier survival statistics and Cox regression analysis were performed. The thyroid cancer ceRNA network was constructed based on the miRDB, miRTarBase, and TargetScan databases.

Results

There were 1,098 mRNAs associated with thyroid cancer; 101 mRNAs were associated with overall survival (OS). Multivariate analysis developed a risk scoring system that identified seven signature mRNAs, with a discriminative value of 0.88, determined by receiver operating characteristic (ROC) curve analysis. A ceRNA network included 13 mRNAs, 31 lncRNAs, and seven miRNAs. Four out of the 31 lncRNAs and all miRNAs were down-regulated, and the remaining RNAs were upregulated. Two lncRNAs (MIR1281A2HG and OPCML-IT1) and one miRNA (miR-184) were significantly associated with OS in patients with thyroid cancer.

Conclusions

Differential RNA expression profiling in thyroid cancer was used to construct a ceRNA network of mRNAs, lncRNAs, and miRNAs that showed potential in evaluating prognosis.

Effect of PTEN inactivating germline mutations on innate immune cell function and thyroid cancer-induced macrophages in patients with PTEN hamartoma tumor syndrome

PTEN hamartoma tumor syndrome (PHTS) is caused by inactivating germline PTEN mutations with subsequent activation of Akt-mTOR signaling, leading to an increased risk of developing thyroid carcinoma (TC). Activation of Akt-mTOR signaling is essential for innate immune cell activation and reprogramming of TC-induced macrophages. Here, we aim to assess the effect of PTEN mutations on innate immune cell function in PHTS patients, especially in the context of TC, using a unique ex vivo model. Monocyte-derived cytokine responses were assessed in 29 PHTS patients and 29 controls. To assess the functional profile of TC-induced-macrophages, a co-culture model with two TC cell lines was performed. Rapamycin, a lactate transport blocker and metformin were used as modulators of the Akt-mTOR pathway and cell metabolism. Monocytes from PHTS patients showed increased production of IL-6, TNF-α, IL-8 and MCP-1, and higher lactate production. After co-culture with TC cell lines, TC-induced macrophages showed significantly increased production of cytokines in both patients and controls, especially after co-culture with a PTEN-deficient TC cell line; these effects were abolished after use of rapamycin or a lactate transport blocker. Metformin blocked the production of anti-inflammatory cytokines. In conclusion, innate immune cells from PHTS patients have increased lactate production and a more proinflammatory phenotype, especially after co-culture with PTEN-deficient TC. Metformin promotes a proinflammatory phenotype by blocking anti-inflammatory cytokine response, whereas rapamycin reduces production of proinflammatory cytokines. This indicates that PHTS patients may benefit from treatment with mTOR blocking agents to limit the inflammatory response in the tumor microenvironment.

Hypoxia-induced pulmonary hypertension and chronic lung disease: caveolin-1 dysfunction an important underlying feature

Caveolin-1 (cav-1) has been shown to play a significant role in the pathogenesis of pulmonary hypertension (PH). In the monocrotaline model of PH, the loss of endothelial cav-1 as well as reciprocal activation of proliferative and anti-apoptotic pathways initiate the disease process and facilitate its progression. In order to examine the role of cav-1 in hypoxia-induced PH, we exposed rats and neonatal calves to hypobaric hypoxia and obtained hemodynamic data and assessed the expression of cav-1 and related proteins eNOS, HSP90, PTEN, gp130, PY-STAT3, β-catenin, and Glut1 in the lung tissue. Chronic hypoxic exposure in rats (48 h-4 weeks) and calves (two weeks) did not alter the expression of cav-1, HSP90, or eNOS. PTEN expression was significantly decreased accompanied by PY-STAT3 activation and increased expression of gp130, Glut1, and β-catenin in hypoxic animals. We also examined cav-1 expression in the lung sections from steers with chronic hypoxic disease (Brisket disease) and from patients with chronic lung disease who underwent lung biopsy for medical reasons. There was no cav-1 loss in Brisket disease. In chronic lung disease cases, endothelial cav-1 expression was present, albeit with less intense staining in some cases. In conclusion, hypoxia did not alter the cav-1 expression in experimental models. The presence of cav-1, however, did not suppress hypoxia-induced activation of PY-STAT3 and β catenin, increased gp130 and Glut1 expression, or prevent the PTEN loss, indicating cav-1 dysfunction in hypoxia-induced PH.

DISC1 regulates lactate metabolism in astrocytes: implications for psychiatric disorders

Our knowledge of how genetic risk variants contribute to psychiatric disease is mainly limited to neurons. However, the mechanisms whereby the same genetic risk factors could affect the physiology of glial cells remain poorly understood. We studied the role of a psychiatric genetic risk factor, Disrupted-In-Schizophrenia-1 (DISC1), in metabolic functions of astrocytes. We evaluated the effects of knockdown of mouse endogenous DISC1 (DISC1-KD) and expression of a dominant-negative, C-terminus truncated human DISC1 (DN-DISC1) on the markers of energy metabolism, including glucose uptake and lactate production, in primary astrocytes and in mice with selective expression of DN-DISC1 in astrocytes. We also assessed the effects of lactate treatment on altered affective behaviors and impaired spatial memory in DN-DISC1 mice. Both DISC1-KD and DN-DISC1 comparably decreased mRNA and protein levels of glucose transporter 4 and glucose uptake by primary astrocytes. Decreased glucose uptake was associated with reduced oxidative phosphorylation and glycolysis as well as diminished lactate production in vitro and in vivo. No significant effects of DISC1 manipulations in astrocytes were observed on expression of the subunits of the electron transport chain complexes or mitofilin, a neuronal DISC1 partner. Lactate treatment rescued the abnormal behaviors in DN-DISC1 male and female mice. Our results suggest that DISC1 may be involved in the regulation of lactate production in astrocytes to support neuronal activity and associated behaviors. Abnormal expression of DISC1 in astrocytes and resulting abnormalities in energy supply may be responsible for aspects of mood and cognitive disorders observed in patients with major psychiatric illnesses.

The emerging co-regulatory role of long noncoding RNAs in epithelial-mesenchymal transition and the Warburg effect in aggressive tumors

Malignant tumor cells have several unique characteristics, and their ability to undergo epithelial-mesenchymal transition (EMT) is a molecular gateway to invasive behavior. Rapid proliferation and increased invasiveness during EMT enhance aberrant glucose metabolism in tumor cells. Meanwhile, aerobic glycolysis provides energy, biosynthesis precursors, and an appropriate microenvironment to facilitate EMT. Reciprocal crosstalk between the processes synergistically contributes to malignant cancer behaviors, but the regulatory mechanisms underlying this interaction remain unclear. Long non-coding RNAs (lncRNAs) are a recently recognized class of RNAs involved in multiple physiological and pathological tumor activities. Increasing evidence indicates that lncRNAs play overlapping roles in both EMT and cancer metabolism. In this review, we describe the lncRNAs reportedly involved in the two biological processes and explore the detailed mechanisms that could help elucidate this co-regulatory network and provide a theoretical basis for clinical management of EMT-related malignant phenotypes.

Impairing energy metabolism in solid tumors through agents targeting oncogenic signaling pathways

Cell metabolic reprogramming is one of the main hallmarks of cancer and many oncogenic pathways that drive the cancer-promoting signals also drive the altered metabolism. This review focuses on recent data on the use of oncogene-targeting agents as potential modulators of deregulated metabolism in different solid cancers. Many drugs, originally designed to inhibit a specific target, then have turned out to have different effects involving also cell metabolism, which may contribute to the mechanisms underlying the growth inhibitory activity of these drugs. Metabolic reprogramming may also represent a way by which cancer cells escape from the selective pressure of targeted drugs and become resistant. Here we discuss how targeting metabolism could emerge as a new effective strategy to overcome such resistance. Finally, accumulating evidence indicates that cancer metabolic rewiring may have profound effects on tumor-infiltrating immune cells. Modulating cancer metabolic pathways through oncogene-targeting agents may not only restore more favorable conditions for proper lymphocytes activation, but also increase the persistence of memory T cells, thereby improving the efficacy of immune-surveillance.

PTEN dephosphorylates AKT to prevent the expression of GLUT1 on plasmamembrane and to limit glucose consumption in cancer cells

GLUT1 is the facilitative transporter playing the major role in the internalization of glucose. Basally, GLUT1 resides on vesicles located in a para-golgian area, and is translocated onto the plasmamembrane upon activation of the PI3KC1-AKT pathway. In proliferating cancer cells, which demand a high quantity of glucose for their metabolism, GLUT1 is permanently expressed on the plasmamembrane. This is associated with the abnormal activation of the PI3KC1-AKT pathway, consequent to the mutational activation of PI3KC1 and/or the loss of PTEN. The latter, in fact, could antagonize the phosphorylation of AKT by limiting the availability of Phosphatidylinositol (3,4,5)-trisphosphate. Here, we asked whether PTEN could control the plasmamembrane expression of GLUT1 also through its protein-phosphatase activity on AKT. Experiments of co-immunoprecipitation and in vitro de-phosphorylation assay with homogenates of cells transgenically expressing the wild type or knocked-down mutants (lipid-phosphatase, protein-phosphatase, or both) isoforms demonstrated that indeed PTEN physically interacts with AKT and drives its dephosphorylation, and so limiting the expression of GLUT1 at the plasmamembrane. We also show that growth factors limit the ability of PTEN to dephosphorylate AKT. Our data emphasize the fact that PTEN acts in two distinct steps of the PI3k/AKT pathway to control the expression of GLUT1 at the plasmamembrane and, further, add AKT to the list of the protein substrates of PTEN.

A novel genomic signature predicting FDG uptake in diverse metastatic tumors

BACKGROUND

Building a universal genomic signature predicting the intensity of FDG uptake in diverse metastatic tumors may allow us to understand better the biological processes underlying this phenomenon and their requirements of glucose uptake.

METHODS

A balanced training set (n = 71) of metastatic tumors including some of the most frequent histologies, with matched PET/CT quantification measurements and whole human genome gene expression microarrays, was used to build the signature. Selection of microarray features was carried out exclusively on the basis of their strong association with FDG uptake (as measured by SUVmean35) by means of univariate linear regression. A thorough bioinformatics study of these genes was performed, and multivariable models were built by fitting several state of the art regression techniques to the training set for comparison.

RESULTS

The 909 probes with the strongest association with the SUVmean35 (comprising 742 identifiable genes and 62 probes not matched to a symbol) were used to build the signature. Partial least squares using three components (PLS-3) was the best performing model in the training dataset cross-validation (root mean square error, RMSE = 0.443) and was validated further in an independent validation dataset (n = 13) obtaining a performance within the 95% CI of that obtained in the training dataset (RMSE = 0.645). Significantly overrepresented biological processes correlating with the SUVmean35 were identified beyond glycolysis, such as ribosome biogenesis and DNA replication (correlating with a higher SUVmean35) and cytoskeleton reorganization and autophagy (correlating with a lower SUVmean35).

CONCLUSIONS

PLS-3 is a signature predicting accurately the intensity of FDG uptake in diverse metastatic tumors. FDG-PET might help in the design of specific targeted therapies directed to counteract the identified malignant biological processes more likely activated in a tumor as inferred from the SUVmean35 and also from its variations in response to antineoplastic treatments.

Targeting KRAS Mutant CMS3 Subtype by Metabolic Inhibitors

Cancer cells rewire their metabolism in order to boost growth, survival, proliferation, and chemoresistance. The common event of this aberrant metabolism is the increased glucose uptake and fermentation of glucose to lactate. This phenomenon is observed even in the presence of O₂ and completely functioning mitochondria. This is known as the "Warburg Effect" and it is a hallmark in cancer. Up to 40% of all CRC's are known to have a mutated (abnormal) KRAS gene, found at differing frequencies in all consensus molecular subtypes (CMS). CMS3 colon cancer molecular subtype contains the so-called 'metabolic tumours' which represents 13% of total CR cases. These tumours display remarkable metabolic deregulation, often showing KRAS mutations (68%). Unfortunately, patients harbouring mutated KRAS are unlikely to benefit from anti-EGFR therapies. Moreover, it remains unclear that patients with KRAS wild-type CRC will definitely respond to such therapies. Although some clinically designed-strategies to modulate KRAS aberrant activation have been designed, all attempts to target KRAS have failed in the clinical assays and KRAS has been assumed to be invulnerable to chemotherapeutic attack. Quest for metabolic inhibitors with anti-tumour activity may constitute a novel and hopeful approach in order to handle KRAS dependent chemoresistance in colon cancer.

Metabolic Alterations of Thyroid Cancer as Potential Therapeutic Targets

Thyroid cancer (TC) is the most frequent endocrine tumor with a growing incidence worldwide. Besides the improvement of diagnosis, TC increasing incidence is probably due to environmental factors and lifestyle modifications. The actual diagnostic criteria for TC classification are based on fine needle biopsy (FNAB) and histological examination following thyroidectomy. Since in some cases it is not possible to make a proper diagnosis, classical approach needs to be supported by additional biomarkers. Recently, new emphasis has been given to the altered cellular metabolism of proliferating cancer cells which require high amount of glucose for energy production and macromolecules biosynthesis. Also TC displays alteration of energy metabolism orchestrated by oncogenes activation and tumor suppressors inactivation leading to abnormal proliferation. Furthermore, TC shows significant metabolic heterogeneity within the tumor microenvironment and metabolic coupling between cancer and stromal cells. In this review we focus on the current knowledge of metabolic alterations of TC and speculate that targeting TC metabolism may improve current therapeutic protocols for poorly differentiated TC. Future studies will further deepen the actual understandings of the metabolic phenotype of TC cells and will give the chance to provide novel prognostic biomarkers and therapeutic targets in tumors with a more aggressive behavior.

Antibody to human α-fetoprotein inhibits cell growth of human hepatocellular carcinoma cells by resuscitating the PTEN molecule: in vitro experiments

It has been proposed that α-fetoprotein (AFP) is a new member of the intracellular signaling molecule family of the phosphoinositide 3-kinase (PI3K)/AKT signaling pathway via interaction with the phosphatase and tensin homolog (PTEN). In this study, the effects of anti-human AFP antibody on the functions of PTEN were examined using an AFP-producing human hepatoma cell line. The antibody caused significant inhibition of cell growth, compared to a normal IgG control, with the accumulation of intracellular immune complexes followed by significant reduction of cytosolic functional AFP. Decrease in the amount of AKT phosphorylated on serine (S) 473 indicated that PI3K/AKT signaling was suppressed in the cells. S380-phosphorylated PTEN increased markedly by the second day after antibody treatment, with slight but significant increase in the PTEN protein level. Since phosphorylation at S380 is critical for PTEN stability, the increase in S380-phosphorylated PTEN indicated maintenance of the number of PTEN molecules and the related potential to control PI3K/AKT signaling. p53 protein (P53) significantly, but slightly increased during antibody treatment, because PTEN expression increased the stability and function of P53 via both molecular interactions. P53 phosphorylated at S20 or at S392 dramatically increased, suggesting an increase in the stability, accumulation and activation of P53. Glucose transporter 1 (GLUT1) increased immediately after antibody treatment, pointing to a deficiency of glucose in the cells. Immunofluorescence cytology revealed that antibody-treatment re-distributed GLUT1 molecules throughout the cytoplasm with a reduction of their patchy localization on the cell surface. This suggested that translocation of GLUT1 depends on the PI3K/AKT pathway, in particular on PTEN expression. Antibody therapy targeted at AFP-producing tumor cells showed an inhibitory effect on the PI3K/AKT pathway via the liberation, restoration and functional stabilization of PTEN. PTEN simultaneously induced both P53 activation and intracellular translocation of GLUT1, since these are closely associated with PTEN.

Interplay between epigenetics and metabolism in oncogenesis: mechanisms and therapeutic approaches

Epigenetic and metabolic alterations in cancer cells are highly intertwined. Oncogene-driven metabolic rewiring modifies the epigenetic landscape via modulating the activities of DNA and histone modification enzymes at the metabolite level. Conversely, epigenetic mechanisms regulate the expression of metabolic genes, thereby altering the metabolome. Epigenetic-metabolomic interplay has a critical role in tumourigenesis by coordinately sustaining cell proliferation, metastasis and pluripotency. Understanding the link between epigenetics and metabolism could unravel novel molecular targets, whose intervention may lead to improvements in cancer treatment. In this review, we summarized the recent discoveries linking epigenetics and metabolism and their underlying roles in tumorigenesis; and highlighted the promising molecular targets, with an update on the development of small molecule or biologic inhibitors against these abnormalities in cancer.

Endothelial and circulating C19MC microRNAs are biomarkers of infantile hemangioma

Infantile hemangioma (IH) is the most common vascular tumor of infancy, and it uniquely regresses in response to oral propranolol. MicroRNAs (miRNAs) have emerged as key regulators of vascular development and are dysregulated in many disease processes, but the role of miRNAs in IH growth has not been investigated. We report expression of C19MC, a primate-specific megacluster of miRNAs expressed in placenta with rare expression in postnatal tissues, in glucose transporter 1-expressing (GLUT-1-expressing) IH endothelial cells and in the plasma of children with IH. Tissue or circulating C19MC miRNAs were not detectable in patients having 9 other types of vascular anomalies or unaffected children, identifying C19MC miRNAs as the first circulating biomarkers of IH. Levels of circulating C19MC miRNAs correlated with IH tumor size and propranolol treatment response, and IH tissue from children treated with propranolol or from children with partially involuted tumors contained lower levels of C19MC miRNAs than untreated, proliferative tumors, implicating C19MC miRNAs as potential drivers of IH pathogenesis. Detection of C19MC miRNAs in the circulation of infants with IH may provide a specific and noninvasive means of IH diagnosis and identification of candidates for propranolol therapy as well as a means to monitor treatment response.

Reprogramming of glucose, fatty acid and amino acid metabolism for cancer progression

Metabolic reprogramming is widely observed during cancer development to confer cancer cells the ability to survive and proliferate, even under the stressed, such as nutrient-limiting, conditions. It is famously known that cancer cells favor the "Warburg effect", i.e., the enhanced glycolysis or aerobic glycolysis, even when the ambient oxygen supply is sufficient. In addition, deregulated anabolism/catabolism of fatty acids and amino acids, especially glutamine, serine and glycine, have been identified to function as metabolic regulators in supporting cancer cell growth. Furthermore, extensive crosstalks are being revealed between the deregulated metabolic network and cancer cell signaling. These exciting advancements have inspired new strategies for treating various malignancies by targeting cancer metabolism. Here we review recent findings related to the regulation of glucose, fatty acid and amino acid metabolism, their crosstalk, and relevant cancer therapy strategy.

PTEN: Multiple Functions in Human Malignant Tumors

PTEN is the most important negative regulator of the PI3K signaling pathway. In addition to its canonical, PI3K inhibition-dependent functions, PTEN can also function as a tumor suppressor in a PI3K-independent manner. Indeed, the PTEN network regulates a broad spectrum of biological functions, modulating the flow of information from membrane-bound growth factor receptors to nuclear transcription factors, occurring in concert with other tumor suppressors and oncogenic signaling pathways. PTEN acts through its lipid and protein phosphatase activity and other non-enzymatic mechanisms. Studies conducted over the past 10 years have expanded our understanding of the biological role of PTEN, showing that in addition to its ability to regulate proliferation and cell survival, it also plays an intriguing role in regulating genomic stability, cell migration, stem cell self-renewal, and tumor microenvironment. Changes in PTEN protein levels, location, and enzymatic activity through various molecular mechanisms can generate a continuum of functional PTEN levels in inherited syndromes, sporadic cancers, and other diseases. PTEN activity can indeed, be modulated by mutations, epigenetic silencing, transcriptional repression, aberrant protein localization, and post-translational modifications. This review will discuss our current understanding of the biological role of PTEN, how PTEN expression and activity are regulated, and the consequences of PTEN dysregulation in human malignant tumors.