New aspects of the Warburg effect in cancer cell biology

Melatonin changes energy metabolism and reduces oncogenic signaling in ovarian cancer cells

Ovarian cancer (OC) adjusts energy metabolism in favor of its progression and dissemination. Because melatonin (Mel) has antitumor actions, we investigated its impact on energy metabolism and kinase signaling in OC cells (SKOV-3 and CAISMOV-24). Cells were divided into control and Mel-treated groups, in the presence or absence of the antagonist luzindole. There was a decrease in the levels of HIF-1α, G6PDH, GAPDH, PDH, and CS after Mel treatment even in the presence of luzindole in both OC cells. Mel treatment also reduced the activity of OC-related enzymes including PFK-1, G6PDH, LDH, CS, and GS whereas PDH activity was increased. Lactate and glutamine levels dropped after Mel treatment. Mel further promoted a reduction in the concentrations of CREB, JNK, NF-kB, p-38, ERK1/2, AKT, P70S6K, and STAT in both cell lines. Mel reverses Warburg-type metabolism and possibly reduces glutaminolysis, thereby attenuating various oncogenic molecules associated with OC progression and invasion.

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.

Metformin Increases the Response of Cholangiocarcinoma Cells to Gemcitabine by Suppressing Pyruvate Kinase M2 to Activate Mitochondrial Apoptosis

BACKGROUND

Cholangiocarcinoma (CCA) is a malignant tumor with a high mortality rate. Resistance to chemotherapy remains a major challenge related to cancer treatment, and increasing the sensitivity of cancer cells to therapeutic drugs is a major focus of cancer treatment.

AIMS

We purposed to explore the role of Metformin in CCA involved in chemotherapeutic sensitivity and Pyruvate kinase M2 (PKM2) through regulating mitochondrial apoptosis in the present study.

METHODS

CCA cell lines of HCC9810 and RBE were treated with Metformin companied with antagonists or agonists of PKM2, cells sensitivity to Gemcitabine, cell migration and invasion along with apoptosis, which is mediated by JC-1 and LDH were assayed.

RESULTS

Our results indicated that Metformin and Gemcitabine exhibit synergistic effect on inhibition of cholangiocarcinoma cell viability, cell migration and invasion as well as promotion apoptosis of cholangiocarcinoma cells. In vivo, Metformin combined with Gemcitabine has cooperation in inhibiting the growth of cholangiocarcinoma cell-derived tumors. Moreover, Metformin and Gemcitabine inhibited expression of PKM2 and PDHB in HCC9810 and RBE.

CONCLUSION

Our study suggested that Metformin may increase the response of cholangiocarcinoma cells to Gemcitabine by suppressing PKM2 to activate mitochondrial apoptosis.

The risk of prostate cancer on incidental finding of an avid prostate uptake on 2-deoxy-2-[18F]fluoro-d-glucose positron emission tomography/computed tomography for non-prostate cancer-related pathology: A single centre retrospective study

Objective

To review the risk of prostate cancer (PCa) in men with incidentally reported increased intraprostatic uptake at 2-deoxy-2-[18F]fluoro-d-glucose positron emission tomography/computed tomography (18F-FDG PET/CT) ordered at Department of Urology, The Wesley Hospital, Brisbane, QLD, Australia for non-PCa related pathology.

Methods

Retrospective analysis of consecutive men between August 2014 and August 2019 presenting to a single institution for 18F-FDG PET/CT for non-prostate related conditions was conducted. Men were classified as benign, indeterminate, or malignant depending of the results of prostate-specific antigen (PSA), PSA velocity, biopsy histopathology, and three-Tesla (3 T) multiparametric MRI (mpMRI) Prostate Imaging Reporting and Data System score, or gallium-68-prostate-specific membrane antigen (68Ga-PSMA) PET/CT results.

Results

Three percent (273/9122) of men demonstrated 18F-FDG avidity within the prostate. Eighty-five percent (231/273) were further investigated, including with PSA tests (227/231, 98.3%), 3 T mpMRI (68/231, 29.4%), 68Ga-PSMA PET/CT (33/231, 14.3%), and prostate biopsy (57/231, 24.7%). Results were considered benign in 130/231 (56.3%), indeterminate in 31/231 (13.4%), and malignant in 70/231 (30.3%). PCa was identified in 51/57 (89.5%) of the men who proceeded to biopsy, including 26/27 (96.3%) men with Prostate Imaging Reporting and Data System scores 4-5 mpMRI and six men with a positive 68Ga-PSMA PET/CT. The most common Gleason score on biopsy was greater than or equal to 4+5 (14/51, 27.5%). 68Ga-PSMA PET/CT was concordant with the 18F-FDG findings in 26/33 (78.8%). All 13 men with a positive concordant 18F-FDG, 3 T mpMRI, and 68Ga-PSMA PET/CT had PCa on biopsy. There was no statistically significant difference in the 18F-FDG maximum standardized uptake value between the benign or malignant groups (5.7 vs. 6.1; p=0.580).

Conclusion

In this study, after an incidental finding of an avid intraprostatic lesion on 18F-FDG PET/CT, 70 of the 231 cases (30.3%; 0.8% of the entire cohort) had results consistent with PCa, most commonly as Gleason score greater than or equal to 4+5 disease. Unless there is limited life expectancy due to competing medical co-morbidity, men with an incidental finding of intraprostatic uptake on 18F-FDG should be further investigated using principles of PCa detection.

Sortilin-Driven Cancer Secretome Enhances Tumorigenic Properties of Hepatocellular Carcinoma via de Novo Lipogenesis

A growing body of evidence suggests de novo lipogenesis as a key metabolic pathway adopted by cancers to fuel tumorigenic processes. While increased de novo lipogenesis has also been reported in hepatocellular carcinoma (HCC), understanding on molecular mechanisms driving de novo lipogenesis remains limited. In the present study, the functional role of sortilin, a member of the vacuolar protein sorting 10 protein receptor family, in HCC was investigated. Sortilin was overexpressed in HCC and was associated with poorer survival outcome. In functional studies, sortilin-overexpressing cells conferred tumorigenic phenotypes, namely, self-renewal and metastatic potential, of HCC cells via the cancer secretome. Proteomic profiling highlighted fatty acid metabolism as a potential molecular pathway associated with sortilin-driven cancer secretome. This finding was validated by the increased lipid content and expression of fatty acid synthase (FASN) in HCC cells treated with conditioned medium collected from sortilin-overexpressing cells. The enhanced tumorigenic properties endowed by sortilin-driven cancer secretome were partly abrogated by co-administration of FASN inhibitor C75. Further mechanistic dissection suggested protein stabilization by post-translational modification with O-GlcNAcylation as a major mechanism leading to augmented FASN expression. In conclusion, the present study uncovered the role of sortilin in hepatocarcinogenesis via modulation of the cancer secretome and deregulated lipid metabolism.

Defining metabolic flexibility in hair follicle stem cell induced squamous cell carcinoma

Among the numerous changes associated with the transformation to cancer, cellular metabolism is one of the first discovered and most prominent[1, 2]. However, despite the knowledge that nearly every cancer is associated with the strong upregulation of various metabolic pathways, there has yet to be much clinical progress on the treatment of cancer by targeting a single metabolic enzyme directly[3-6]. We previously showed that inhibition of glycolysis through lactate dehydrogenase (LDHA) deletion in cancer cells of origin had no effect on the initiation or progression of cutaneous squamous cell carcinoma[7], suggesting that these cancers are metabolically flexible enough to produce the necessary metabolites required for sustained growth in the absence of glycolysis. Here we focused on glutaminolysis, another metabolic pathway frequently implicated as important for tumorigenesis in correlative studies. We genetically blocked glutaminolysis through glutaminase (GLS) deletion in cancer cells of origin, and found that this had little effect on tumorigenesis, similar to what we previously showed for blocking glycolysis. Tumors with genetic deletion of glutaminolysis instead upregulated lactate consumption and utilization for the TCA cycle, providing further evidence of metabolic flexibility. We also found that the metabolic flexibility observed upon inhibition of glycolysis or glutaminolysis is due to post-transcriptional changes in the levels of plasma membrane lactate and glutamine transporters. To define the limits of metabolic flexibility in cancer initiating hair follicle stem cells, we genetically blocked both glycolysis and glutaminolysis simultaneously and found that frank carcinoma was not compatible with abrogation of both of these carbon utilization pathways. These data point towards metabolic flexibility mediated by regulation of nutrient consumption, and suggest that treatment of cancer through metabolic manipulation will require multiple interventions on distinct pathways.

Association between adjuvant therapy and survival in colorectal cancer patients according to metabolic Warburg-subtypes

PURPOSE

Tumor location and tumor node metastasis (TNM) stage guide treatment decisions in colorectal cancer (CRC) patients. However, patients with the same disease stage do not benefit equally from adjuvant therapy. Hence, there remains an urgent clinical need to identify prognostic and/or predictive biomarker(s) to personalize treatment decisions. In this exploratory study, we investigated whether our previously defined metabolic Warburg-subtypes can predict which CRC patients might derive survival benefit from adjuvant therapy.

METHODS

Information regarding treatment (surgery only: n = 1451; adjuvant radiotherapy: n = 82; or adjuvant chemotherapy: n = 260) and Warburg-subtype (Warburg-low: n = 485, -moderate: n = 641, or -high: n = 667) was available for 1793 CRC patients from the Netherlands Cohort Study (NLCS). Kaplan-Meier curves and Cox regression models were used to investigate survival benefit from adjuvant therapy compared to surgery-only for the different Warburg-subtypes.

RESULTS

Patients with Warburg-moderate CRC (HRCRC-specific 0.64; 95% CI 0.47-0.86, HRoverall 0.61; 95% CI 0.47-0.80), and possibly Warburg-high CRC (HRCRC-specific 0.86; 95% CI 0.65-1.14, HRoverall 0.82; 95% CI 0.64-1.05), had survival benefit from adjuvant therapy. No survival benefit was observed for patients with Warburg-low CRC (HRCRC-specific 1.07; 95% CI 0.76-1.52, HRoverall 0.95; 95% CI 0.70-1.30). There was a significant interaction between Warburg-subtype and adjuvant therapy for CRC-specific survival (p = 0.049) and overall survival (p = 0.035).

CONCLUSION

Our results suggest that Warburg-subtypes may predict survival benefit from adjuvant therapy in CRC patients. A survival benefit from adjuvant therapy was observed for patients with Warburg-moderate and possibly Warburg-high CRC, but not for patients with Warburg-low CRC. Future prospective studies are necessary to validate our findings.

Metabolic reprogramming, oxidative stress, and pulmonary hypertension

Mitochondria are highly dynamic organelles essential for cell metabolism, growth, and function. It is becoming increasingly clear that endothelial cell dysfunction significantly contributes to the pathogenesis and vascular remodeling of various lung diseases, including pulmonary arterial hypertension (PAH), and that mitochondria are at the center of this dysfunction. The more we uncover the role mitochondria play in pulmonary vascular disease, the more apparent it becomes that multiple pathways are involved. To achieve effective treatments, we must understand how these pathways are dysregulated to be able to intervene therapeutically. We know that nitric oxide signaling, glucose metabolism, fatty acid oxidation, and the TCA cycle are abnormal in PAH, along with alterations in the mitochondrial membrane potential, proliferation, and apoptosis. However, these pathways are incompletely characterized in PAH, especially in endothelial cells, highlighting the urgent need for further research. This review summarizes what is currently known about how mitochondrial metabolism facilitates a metabolic shift in endothelial cells that induces vascular remodeling during PAH.

Noncanonical role of singleminded-2s in mitochondrial respiratory chain formation in breast cancer

Dysregulation of cellular metabolism is a hallmark of breast cancer progression and is associated with metastasis and therapeutic resistance. Here, we show that the breast tumor suppressor gene SIM2 promotes mitochondrial oxidative phosphorylation (OXPHOS) using breast cancer cell line models. Mechanistically, we found that SIM2s functions not as a transcription factor but localizes to mitochondria and directly interacts with the mitochondrial respiratory chain (MRC) to facilitate functional supercomplex (SC) formation. Loss of SIM2s expression disrupts SC formation through destabilization of MRC Complex III, leading to inhibition of electron transport, although Complex I (CI) activity is retained. A metabolomic analysis showed that knockout of SIM2s leads to a compensatory increase in ATP production through glycolysis and accelerated glutamine-driven TCA cycle production of NADH, creating a favorable environment for high cell proliferation. Our findings indicate that SIM2s is a novel stabilizing factor required for SC assembly, providing insight into the impact of the MRC on metabolic adaptation and breast cancer progression.

The In-Vitro Effect of Homeopathically Prepared Rubus idaeus and 680 nm Laser Irradiation on Cervical Cancer Cells

BACKGROUND

 Cervical cancer (CC) is the second leading cancer in women and is the most common in those aged 15 to 44 years. Medicinal plant extracts have been used as homeopathic preparations for health benefits. Rubus idaeus (RI) is used to treat disorders of the female genital tract and produces cytotoxic effects. However, the use of homeopathically prepared RI in combination with low level laser therapy has not previously been explored.

AIM

 The study aims to investigate the in-vitro effects of homeopathically prepared RI alone and in combination as a potential photosensitizer with Low-level laser irradiation (LLLI) at fluencies of 5, 10, and 15 J/cm².

METHODS

 HeLa CC cells were treated with RI (D3, D6, and 30cH homeopathic preparations). Cells were then treated with RI IC₅₀ and 680 nm laser diode at 5, 10, and 15 J/cm² fluencies, and the results compared with untreated control cells. Trypan blue viability, lactate dehydrogenase (LDH) cytotoxicity, and adenosine triphosphate (ATP) proliferation assays were used to analyze the cellular dose-responses along with inverted microscopy, Hoechst staining and Annexin-V/PI staining.

RESULTS

 RI D3 alone demonstrated an ability to reduce cellular viability to 59% and also to reduce ATP levels. The subsequent combined treatment protocol of RI D3 with all fluencies of laser demonstrated an increase in cellular ATP and increased LDH levels compared with the control.

CONCLUSION

 The increased ATP and LDH levels observed in the combined treatment protocol of 680 nm laser and RI D3 at fluencies of 5, 10 and 15 J/cm², show that the Warburg effect might have been induced in the CC cells - an increase in glucose uptake and the preferential production of lactate, even in the presence of oxygen. More research, including work on other cell lines, needs to be conducted to identify if RI and perhaps a different wavelength of laser irradiation could have potential in inducing cell death in cancer cells.

Disturbed Cardiac Metabolism Triggers Atrial Arrhythmogenesis in Diabetes Mellitus: Energy Substrate Alternate as a Potential Therapeutic Intervention

Atrial fibrillation (AF) is the most common type of sustained arrhythmia in diabetes mellitus (DM). Its morbidity and mortality rates are high, and its prevalence will increase as the population ages. Despite expanding knowledge on the pathophysiological mechanisms of AF, current pharmacological interventions remain unsatisfactory; therefore, novel findings on the underlying mechanism are required. A growing body of evidence suggests that an altered energy metabolism is closely related to atrial arrhythmogenesis, and this finding engenders novel insights into the pathogenesis of the pathophysiology of AF. In this review, we provide comprehensive information on the mechanistic insights into the cardiac energy metabolic changes, altered substrate oxidation rates, and mitochondrial dysfunctions involved in atrial arrhythmogenesis, and suggest a promising advanced new therapeutic approach to treat patients with AF.

Perineural invasion-associated biomarkers for tumor development

Perineural invasion (PNI) is the process of neoplastic invasion of peripheral nerves and is considered to be the fifth mode of cancer metastasis. PNI has been detected in head and neck tumors and pancreatic, prostate, bile duct, gastric, and colorectal cancers. It leads to poor prognostic outcomes and high local recurrence rates. Despite the increasing number of studies on PNI, targeted therapeutic modalities have not been proposed. The identification of PNI-related biomarkers would facilitate the non-invasive and early diagnosis of cancers, the establishment of prognostic panels, and the development of targeted therapeutic approaches. In this review, we compile information on the molecular mediators involved in PNI-associated cancers. The expression and prognostic significance of molecular mediators and their receptors in PNI-associated cancers are analyzed, and the possible mechanisms of action of these mediators in PNI are explored, as well as the association of cells in the microenvironment where PNI occurs.

The Anti-Proliferative Lichen-Compound Protolichesterinic Acid Inhibits Oxidative Phosphorylation and Is Processed via the Mercapturic Pathway in Cancer Cells

The lichen compound protolichesterinic acid (PA) has an anti-proliferative effect against several cancer cell lines of different origin. This effect cannot be explained by the known inhibitory activity of PA against 5- and 12-lipoxygenases. The aim was therefore to search for mechanisms for the anti-proliferative activity of PA. Two cancer cell lines of different origin, both sensitive to anti-proliferative effects of PA, were selected for this study, T-47D from breast cancer and AsPC-1 from pancreatic cancer. Morphological changes were assessed by transmission electron microscopy, HPLC coupled with TOF spectrometry was used for metabolomics, mitochondrial function was measured using the Agilent Seahorse XFp Real-time ATP assay and glucose/lactate levels by radiometry. Levels of glutathione, NADP/NADPH and reactive oxygen species [ROS] were measured by luminescence. Following exposure to PA both cell lines showed structural changes in mitochondria that were in line with a measured reduction in oxidative phosphorylation and increased glycolysis. These changes were more marked in T-47D, which had poorer mitochondrial function at baseline. PA was processed and expelled from the cells via the mercapturic pathway, which consumes glutathione. Nevertheless, glutathione levels were increased after 24 hours of exposure to PA, implying enhanced synthesis. Redox balance was not much affected and ROS levels were not increased. We conclude that PA is metabolically processed and expelled from cells, leading indirectly to increased glutathione levels with minimal effects on redox balance. The most marked effect was on mitochondrial structure and metabolic function implying that effects of PA may depend on mitochondrial fitness.

Plants as a Source of Anticancer Agents: From Bench to Bedside

Cancer is the second leading cause of death after cardiovascular diseases. Conventional anticancer therapies are associated with lack of selectivity and serious side effects. Cancer hallmarks are biological capabilities acquired by cancer cells during neoplastic transformation. Targeting multiple cancer hallmarks is a promising strategy to treat cancer. The diversity in chemical structure and the relatively low toxicity make plant-derived natural products a promising source for the development of new and more effective anticancer therapies that have the capacity to target multiple hallmarks in cancer. In this review, we discussed the anticancer activities of ten natural products extracted from plants. The majority of these products inhibit cancer by targeting multiple cancer hallmarks, and many of these chemicals have reached clinical applications. Studies discussed in this review provide a solid ground for researchers and physicians to design more effective combination anticancer therapies using plant-derived natural products.

Association between mutational subgroups, Warburg-subtypes, and survival in patients with colorectal cancer

BACKGROUND

Previous research suggests that Warburg-subtypes are related to potentially important survival differences in colorectal cancer (CRC) patients. In the present study, we investigated whether mutational subgroups based on somatic mutations in RAS, BRAF, PIK3CA, and MET, which are known to promote the Warburg-effect, as well as mismatch repair (MMR) status, hold prognostic value in CRC. In addition, we investigated whether Warburg-subtypes provide additional prognostic information, independent of known prognostic factors like TNM stage.

METHODS

CRC patients (n = 2344) from the prospective Netherlands Cohort Study (NLCS) were classified into eight mutually exclusive mutational subgroups, based on observed mutations in RAS, BRAF, PIK3CA, and MET, and MMR status: All-wild-type + MMR_proficient , KRAS_mut  + MMR_proficient , KRAS_mut  + PIK3CA_mut  + MMR_proficient , PIK3CA_mut  + MMR_proficient , BRAF_mut  + MMR_proficient , BRAF_mut  + MMR_deficient , other + MMR_proficient , and other + MMR_deficient . Kaplan-Meier curves and Cox regression models were used to investigate associations between mutational subgroups and survival, as well as associations between our previously established Warburg-subtypes and survival within these mutational subgroups.

RESULTS

Compared to patients with all-wild-type + MMR_proficient CRC, patients with KRAS_mut  + MMR_proficient , KRAS_mut  + PIK3CA_mut  + MMR_proficient , BRAF_mut  + MMR_proficient , or other + MMR_proficient CRC had a statistically significant worse survival (HR_CRC-specific ranged from 1.29 to 1.88). In contrast, patients with other + MMR_deficient CRC had the most favorable survival (HR_CRC-specific 0.48). No statistically significant survival differences were observed for the Warburg-subtypes within mutational subgroups.

CONCLUSION

Our results highlight the prognostic potential of mutational subgroups in CRC. Warburg-subtypes did not provide additional prognostic information within these mutational subgroups. Future larger-scale prospective studies are necessary to validate our findings and to examine the potential clinical utility of CRC subtyping based on mutational subgroups.

Identification of oncogenic signaling pathways associated with the dimorphic metabolic dysregulations in gastric cancer subtypes

Metabolic dysregulations have been identified as intrinsic hallmarks of cancer cells. Investigations of altered metabolic processes, in the context of the associated oncogenic signaling pathways are expected to pave way for the development of targeted cancer therapeutics. We have recently identified the enrichment of glucose and glutamine metabolism in a subset of intestinal subtype gastric tumors at the level of expression of genes, gene sets and the occurrence of metabolites. On the other hand, glucose transport, glucan and fatty acid metabolism were enriched in a subset of diffuse subtype gastric tumors. In the current study, along with glucose metabolism, mTOR, HSP90, MYC, E2F, P53 and proteasome pathways were found enriched in a subset of intestinal subtype and a part of MSI subtype gastric tumors. On the other hand, along with fatty acid metabolism, the oncogenic pathway KRAS was found to be enriched in a subset of GS tumors among diffuse subtype gastric tumors. Thus, oncogenic signaling pathways associated with two distinct metabolic rewiring which differentially occurs between major gastric cancer subtypes were identified. These pathways seem the potential targets to differentially target these gastric cancer subtypes. Exploratory integrative genomic analyses reveal HSP90 inhibitors, AKT/mTOR inhibitors, and cell cycle inhibitors as potential agents to target the gastric tumors with the rewired glucose metabolism and MEK/MAPK inhibitors as suitable drug candidates to target the diffuse subtype tumors with the dysregulated fatty acid metabolism. This observation would pave way for the selective and targeted use of signaling pathway modulators for targeted and stratified gastric cancer therapeutics.

Connective Tissue Growth Factor in Idiopathic Pulmonary Fibrosis: Breaking the Bridge

CTGF is upregulated in patients with idiopathic pulmonary fibrosis (IPF), characterized by the deposition of a pathological extracellular matrix (ECM). Additionally, many omics studies confirmed that aberrant cellular senescence-associated mitochondria dysfunction and metabolic reprogramming had been identified in different IPF lung cells (alveolar epithelial cells, alveolar endothelial cells, fibroblasts, and macrophages). Here, we reviewed the role of the CTGF in IPF lung cells to mediate anomalous senescence-related metabolic mechanisms that support the fibrotic environment in IPF.

HRD1 in human malignant neoplasms: Molecular mechanisms and novel therapeutic strategy for cancer

In tumor cells, the endoplasmic reticulum (ER) plays an essential role in maintaining cellular proteostasis by stimulating unfolded protein response (UPR) underlying stress conditions. ER-associated degradation (ERAD) is a critical pathway of the UPR to protect cells from ER stress-induced apoptosis and the elimination of unfolded or misfolded proteins by the ubiquitin-proteasome system (UPS). 3-Hydroxy-3-methylglutaryl reductase degradation (HRD1) as an E3 ubiquitin ligase plays an essential role in the ubiquitination and dislocation of misfolded protein in ERAD. In addition, HRD1 can target other normal folded proteins. In various types of cancer, the expression of HRD1 is dysregulated, and it targets different molecules to develop cancer hallmarks or suppress the progression of the disease. Recent investigations have defined the role of HRD1 in drug resistance in types of cancer. This review focuses on the molecular mechanisms of HRD1 and its roles in cancer pathogenesis and discusses the worthiness of targeting HRD1 as a novel therapeutic strategy in cancer.

Short isoform thymic stromal lymphopoietin reduces inflammation and aerobic glycolysis of asthmatic airway epithelium by antagonizing long isoform thymic stromal lymphopoietin

Background

Up-regulation of aerobic glycolysis has been reported as a characterization of asthma and facilitates airway inflammation. We has been previously reported that short isoform thymic stromal lymphopoietin (sTSLP) could reduce inflammation in asthmatic airway epithelial cells. Here we wanted to investigate whether the inhibition of sTSLP on asthma is related to aerobic glycolysis.

Methods

Asthmatic model was established in challenging Male BALB/c mice and 16-HBE (human bronchial epithelial) cell line with house dust mite (HDM). Indicators of glycolysis were assessed to measure whether involve in sTSLP regulating airway epithelial cells inflammation in asthmatic model in vivo and in vitro.

Results

sTSLP decreased inflammation of asthmatic airway and aerobic glycolysis in mice. HDM or long isoform thymic stromal lymphopoietin (lTSLP) promoted HIF-1α expression and aerobic glycolysis by miR-223 to target and inhibit VHL (von Hippel-Lindau) expression 16-HBE. Inhibition of aerobic glycolysis restrained HDM- and lTSLP-induced inflammatory cytokines production. sTSLP along had almost no potential to alter aerobic glycolysis of 16-HBE. But sTSLP decreased LDHA (lactate dehydrogenase A) and LD (Lactic acid) levels in BALF, and HIF-1α and LDHA protein levels in airway epithelial cells of asthma mice model. lTSLP and sTSLP both induced formation of TSLPR and IL-7R receptor complex, and lTSLP obviously facilitated phosphorylation of JAK1, JAK2 and STAT5, while sTSLP induced a little phosphorylation of JAK1 and STAT5.

Conclusion

We identified a novel mechanism that lTSLP could promote inflammatory cytokines production by miR-223/VHL/HIF-1α pathway to upregulate aerobic glycolysis in airway epithelial cells in asthma. This pathway is suppressed by sTSLP through occupying binding site of lTSLP in TSLPR and IL-7R receptor complex.

Cholesterol-Lowering Phytochemicals: Targeting the Mevalonate Pathway for Anticancer Interventions

There are a plethora of cancer causes and the road to fully understanding the carcinogenesis process remains a dream that keeps changing. However, a list of role players that are implicated in the carcinogens process is getting lengthier. Cholesterol is known as bad sterol that is heavily linked with cardiovascular diseases; however, it is also comprehensively associated with carcinogenesis. There is an extensive list of strategies that have been used to lower cholesterol; nevertheless, the need to find better and effective strategies remains vastly important. The role played by cholesterol in the induction of the carcinogenesis process has attracted huge interest in recent years. Phytochemicals can be dubbed as magic tramp cards that humans could exploit for lowering cancer-causing cholesterol. Additionally, the mechanisms that are regulated by phytochemicals can be targeted for anticancer drug development. One of the key role players in cancer development and suppression, Tumour Protein 53 (TP53), is crucial in regulating the biogenesis of cholesterol and is targeted by several phytochemicals. This minireview covers the role of p53 in the mevalonate pathway and how bioactive phytochemicals target the mevalonate pathway and promote p53-dependent anticancer activities.

Hydrogen Sulfide Attenuates the Cognitive Dysfunction in Parkinson's Disease Rats via Promoting Hippocampal Microglia M2 Polarization by Enhancement of Hippocampal Warburg Effect

Identification of innovative therapeutic targets for the treatment of cognitive impairment in Parkinson's disease (PD) is urgently needed. Hydrogen sulfide (H₂S) plays an important role in cognitive function. Therefore, this work is aimed at investigating whether H₂S attenuates the cognitive impairment in PD and the underlying mechanisms. In the rotenone- (ROT-) established PD rat model, NaHS (a donor of H₂S) attenuated the cognitive impairment and promoted microglia polarization from M1 towards M2 in the hippocampus of PD rats. NaHS also dramatically upregulated the Warburg effect in the hippocampus of PD rats. 2-Deoxyglucose (2-DG, an inhibitor of the Warburg effect) abolished NaHS-upregulated Warburg effect in the hippocampus of PD rats. Moreover, the inhibited hippocampal Warburg effect by 2-DG abrogated H₂S-excited the enhancement of hippocampal microglia M2 polarization and the improvement of cognitive function in ROT-exposed rats. Our data demonstrated that H₂S inhibits the cognitive dysfunction in PD via promoting microglia M2 polarization by enhancement of hippocampal Warburg effect.

Redox signaling by glutathione peroxidase 2 links vascular modulation to metabolic plasticity of breast cancer

Redox regulation of breast cancer underlies malignant progression. Loss of the antioxidant glutathione peroxidase 2 in breast cancer cells increases reactive oxygen species, thereby activating hypoxia inducible factor-α (HIF1α) signaling. This in turn causes vascular malfunction, resulting in hypoxia and metabolic heterogeneity. HIF1α suppresses oxidative phosphorylation and stimulates glycolysis (the Warburg effect) in most of the tumor, except for one cancer subpopulation, which was capable of using both metabolic modalities. Hence, adopting a hybrid metabolic state may allow tumor cells to survive under aerobic or hypoxic conditions, a vulnerability that may be exploited for therapeutic targeting by either metabolic or redox-based strategies.

In search of redox mechanisms in breast cancer, we uncovered a striking role for glutathione peroxidase 2 (GPx2) in oncogenic signaling and patient survival. GPx2 loss stimulates malignant progression due to reactive oxygen species/hypoxia inducible factor-α (HIF1α)/VEGFA (vascular endothelial growth factor A) signaling, causing poor perfusion and hypoxia, which were reversed by GPx2 reexpression or HIF1α inhibition. Ingenuity Pathway Analysis revealed a link between GPx2 loss, tumor angiogenesis, metabolic modulation, and HIF1α signaling. Single-cell RNA analysis and bioenergetic profiling revealed that GPx2 loss stimulated the Warburg effect in most tumor cell subpopulations, except for one cluster, which was capable of oxidative phosphorylation and glycolysis, as confirmed by coexpression of phosphorylated-AMPK and GLUT1. These findings underscore a unique role for redox signaling by GPx2 dysregulation in breast cancer, underlying tumor heterogeneity, leading to metabolic plasticity and malignant progression.

Trained Immunity: An Overview and the Impact on COVID-19

Effectively treating infectious diseases often requires a multi-step approach to target different components involved in disease pathogenesis. Similarly, the COVID-19 pandemic has become a global health crisis that requires a comprehensive understanding of Severe Acute Respiratory Syndrome Corona Virus 2 (SARS-CoV-2) infection to develop effective therapeutics. One potential strategy to instill greater immune protection against COVID-19 is boosting the innate immune system. This boosting, termed trained immunity, employs immune system modulators to train innate immune cells to produce an enhanced, non-specific immune response upon reactivation following exposure to pathogens, a process that has been studied in the context of in vitro and in vivo clinical studies prior to the COVID-19 pandemic. Evaluation of the underlying pathways that are essential to inducing protective trained immunity will provide insight into identifying potential therapeutic targets that may alleviate the COVID-19 crisis. Here we review multiple immune training agents, including Bacillus Calmette-Guérin (BCG), β-glucan, and lipopolysaccharide (LPS), and the two most popular cell types involved in trained immunity, monocytes and natural killer (NK) cells, and compare the signaling pathways involved in innate immunity. Additionally, we discuss COVID-19 trained immunity clinical trials, emphasizing the potential of trained immunity to fight SARS-CoV-2 infection. Understanding the mechanisms by which training agents activate innate immune cells to reprogram immune responses may prove beneficial in developing preventive and therapeutic targets against COVID-19.

GCN5-mediated PKM2 acetylation participates in benzene-induced hematotoxicity through regulating glycolysis and inflammation via p-Stat3/IL17A axis

Benzene is a common environmental carcinogen that induces leukemia. Studies suggest that metabolic disorder has a relationship with the toxicity of benzene. Pyruvate kinase M2 (PKM2) is a key rate-limiting enzyme in glycolysis. However, the upstream and downstream regulatory mechanisms of PKM2 in benzene-induced hematotoxicity and the therapeutic effects of targeting PKM2 in vivo are unclear. This study aims to provide insights into the new mechanism of benzene-induced hematotoxicity and reveal the therapeutic significance of targeting PKM2. Herein, we demonstrated that PKM2-dependent glycolysis contributes to benzene-induced hematotoxicity by regulating inflammation reaction. Mechanistically, acetylated proteomics revealed that 1,4-benzoquinone (1,4-BQ) induced acetylation of PKM2 at position K66, and this modification contributed to the increase of PKM2 expression and can be inhibited by inhibition of acetyltransferase GCN5. Meanwhile, the elevated PKM2 was shown to prompt the activation of nuclear phosphorylated Stat3 (p-Stat3) and IL17A. Clinically, pharmacological inhibition of PKM2 alleviated the blood toxicity induced by benzene, which was mainly characterized by an increase in routine blood parameters and improvement of hematopoietic imbalance. Besides, elevated PKM2 is a promising biomarker in people occupationally exposed to benzene. Overall, we identified PKM2/p-Stat3/IL-17A axis participates in the hematotoxicity of benzene, and targeting PKM2 has certain therapeutic implications in hematologic diseases.

A Perspective on Medicinal Chemistry Approaches for Targeting Pyruvate Kinase M2

The allosteric regulation of pyruvate kinase M2 (PKM2) affects the switching of the PKM2 protein between the high-activity and low-activity states that allow ATP and lactate production, respectively. PKM2, in its low catalytic state (dimeric form), is chiefly active in metabolically energetic cells, including cancer cells. More recently, PKM2 has emerged as an attractive target due to its role in metabolic dysfunction and other interrelated conditions. PKM2 (dimer) activity can be inhibited by modulating PKM2 dimer-tetramer dynamics using either PKM2 inhibitors that bind at the ATP binding active site of PKM2 (dimer) or PKM2 activators that bind at the allosteric site of PKM2, thus activating PKM2 from the dimer formation to the tetrameric formation. The present perspective focuses on medicinal chemistry approaches to design and discover PKM2 inhibitors and activators and further provides a scope for the future design of compounds targeting PKM2 with better efficacy and selectivity.

Impact of Cancer Cachexia on Cardiac and Skeletal Muscle: Role of Exercise Training

Simple Summary

Cachexia is a syndrome that can be present in many patients diagnosed with cancer, especially in those with metastatic or very advanced tumors. The patient may present with weight loss, loss of muscle mass, and even cardiac dysfunction as a result of it. The aim of this review is to understand how cachexia manifests and whether physical exercise has any role in trying to prevent or reverse this syndrome in cancer patients.

Abstract

Cachexia is a multifactorial syndrome that presents with, among other characteristics, progressive loss of muscle mass and anti-cardiac remodeling effect that may lead to heart failure. This condition affects about 80% of patients with advanced cancer and contributes to worsening patients’ tolerance to anticancer treatments and to their premature death. Its pathogenesis involves an imbalance in metabolic homeostasis, with increased catabolism and inflammatory cytokines levels, leading to proteolysis and lipolysis, with insufficient food intake. A multimodal approach is indicated for patients with cachexia, with the aim of reducing the speed of muscle wasting and improving their quality of life, which may include nutritional, physical, pharmacologic, and psychological support. This review aims to outline the mechanisms of muscle loss, as well as to evaluate the current clinical evidence of the use of physical exercise in patients with cachexia.

A generic gas chromatography method for determination of residual solvents in PET radiopharmaceuticals

A novel gas chromatography (GC) method for quantitation of volatile organic compounds (VOCs) in ¹⁸F- and ¹¹C-radiopharmaceuticals listed in the European Pharmacopoeia (Ph. Eur.) was proposed. Optimized chromatographic parameters were used for separation of ethanol, acetone, acetonitrile, tetrahydrofuran (THF), dibromomethane (DBM), 2-dimethylaminoethanol (deanol), N,N-dimethylformamide (DMF) and dimethyl sulfoxide (DMSO) which could be detected in radioactive drug samples. The calculated peak resolutions (R_S) were higher than 2.0 at ethanol concentration of up to 11 m/m%. Reproducible results could be obtained using base deactivated fused silica wool as packing material of inlet liner. Validation parameters showed excellent linearity (r² ≥0.9998) in the range from 10 to at least 120% of concentration limit of solvents. The accuracy was determined as recovery of concentrations which ranged from 99.3% to 103.8%. Additionally, the relative standard deviation (RSD) of each solvent for inter-day and intra-day precision were in the range of 0.5-4.2% and 0.4-4.4%, respectively. The limit of quantitation (LOQ) for ethanol, acetone, acetonitrile, THF, DBM, deanol, DMF and DMSO was 0.48, 0.42, 0.43, 0.46, 4.35, 0.73, 0.68 and 0.50 mg/L, respectively. The developed procedure was successively applied for quantitation of ethanol, acetone, acetonitrile and deanol in radioactive drug samples of [¹¹C]methionine, [¹¹C]choline, 2-deoxy-2-[¹⁸F]fluoro-D-glucose ([¹⁸F]FDG) and O-(2-[¹⁸F]fluoroethyl)-L-tyrosine ([¹⁸F]FET). The proposed GC method applying flame ionization detection (FID) could be adapted in routine quality control of most frequently used positron emission tomography (PET) radiopharmaceuticals to perform the determination of residual solvents with analysis time of 12 min.

PET Use in Cancer Diagnosis, Treatment, and Prognosis

Tumorigenesis is a multistep process marked by variations in numerous metabolic pathways that affect cellular architectures and functions. Cancer cells reprogram their energy metabolism to enable several basic molecular functions, including membrane biosynthesis, receptor regulations, bioenergetics, and redox stress. In recent years, cancer diagnosis and treatment strategies have targeted these specific metabolic changes and the tumor's interactions with its microenvironment. Positron emission tomography (PET) captures all molecular alterations leading to abnormal function and cancer progression. As a result, the development of PET radiotracers increasingly focuses on irregular biological pathways or cells that overexpress receptors that have the potential to function as biomarkers for early diagnosis and treatment measurements as well as research. This chapter reviews both established and evolving PET radiotracers used to image tumor biology. We have also included a few advantages and disadvantages of the routinely used PET radiotracers in cancer imaging.

Low Carbohydrate Diets in Cancer Therapeutics: Current Evidence

Low carbohydrate diets have a promising mechanistic rationale in the treatment of cancer with favorable preclinical data. The strongest data suggest synergistic effects of dietary interventions with traditional cancer therapies. Recent prospective clinical trials suggest that low carbohydrate diets are safely and feasibly added within a busy oncology clinic, with hopeful additive effects in treatment enhancement.

Exploring Carbohydrates for Therapeutics: A Review on Future Directions

Carbohydrates are important components of foods and essential biomolecules performing various biological functions in living systems. A variety of biological activities besides providing fuel have been explored and reported for carbohydrates. Some carbohydrates have been approved for the treatment of various diseases; however, carbohydrate-containing drugs represent only a small portion of all of the drugs on the market. This review summarizes several potential development directions of carbohydrate-containing therapeutics, with the hope of promoting the application of carbohydrates in drug development.

Expression of proteins associated with the Warburg-effect and survival in colorectal cancer

Previous research has suggested that the expression of proteins related to the Warburg effect may have prognostic value in colorectal cancer (CRC), but results remain inconsistent. Our objective was to investigate the relationship between Warburg-subtypes and patient survival in a large population-based series of CRC patients. In the present study, we investigated the expression of six proteins related to the Warburg effect (LDHA, GLUT1, MCT4, PKM2, p53, PTEN) by immunohistochemistry on tissue microarrays (TMAs) from 2,399 incident CRC patients from the prospective Netherlands Cohort Study. Expression levels of the six proteins were combined into a pathway-based sum-score and patients were categorised into three Warburg-subtypes (low/moderate/high). The associations between Warburg-subtypes and CRC-specific and overall survival were investigated using Kaplan-Meier curves and Cox regression models. CRC patients were classified as Warburg-low (n = 695, 29.0%), Warburg-moderate (n = 858, 35.8%) or Warburg-high (n = 841, 35.1%). Patients with Warburg-high CRC had the poorest CRC-specific [hazard ratio (HR) 1.17; 95% CI 1.00-1.38] and overall survival (HR 1.19; 95% CI 1.05-1.35), independent of known prognostic factors. In stratified analyses, this was particularly true for patients with tumour-node-metastasis (TNM) stage III CRC (HR_CRC-specific 1.45; 95% CI 1.10-1.92 and HR_overall 1.47; 95% CI 1.15-1.87), and cancers located in the rectum (HR_overall 1.56; 95% CI 1.15-2.13). To our knowledge, this is the first study to identify the prognostic value of immunohistochemistry-based Warburg-subtypes in CRC. Our data suggest that Warburg-subtypes are related to potentially important differences in CRC survival. Further research is required to validate our findings and to investigate the potential clinical utility of these Warburg-subtypes in CRC.

Pan-Cancer Analysis of Glycolytic and Ketone Bodies Metabolic Genes: Implications for Response to Ketogenic Dietary Therapy

Background

The Warburg effect, also termed "aerobic glycolysis", is one of the most remarkable and ubiquitous metabolic characteristics exhibited by cancer cells, representing a potential vulnerability that might be targeted for tumor therapy. Ketogenic diets (KDs), composed of high-fat, moderate-protein and low carbohydrates, are aimed at targeting the Warburg effect for cancer treatment, which have recently gained considerable attention. However, the efficiency of KDs was inconsistent, and the genotypic contribution is still largely unknown.

Methods

The bulk RNA-seq data from The Cancer Genome Atlas (TCGA), single cell RNA sequencing (scRNA-seq), and microarray data from Gene Expression Omnibus (GEO) and Cancer Cell Line Encyclopedia (CCLE) were collected. A joint analysis of glycolysis and ketone bodies metabolism (KBM) pathway was performed across over 10,000 tumor samples and nearly 1,000 cancer cell lines. A series of bioinformatic approaches were combined to identify a metabolic subtype that may predict the response to ketogenic dietary therapy (KDT). Mouse xenografts were established to validate the predictive utility of our subtypes in response to KDT.

Results

We first provided a system-level view of the expression pattern and prognosis of the signature genes from glycolysis and KBM pathway across 33 cancer types. Analysis by joint stratification of glycolysis and KBM revealed four metabolic subtypes, which correlated extensively but diversely with clinical outcomes across cancers. The glycolytic subtypes may be driven by TP53 mutations, whereas the KB-metabolic subtypes may be mediated by CTNNB1 (β-catenin) mutations. The glycolytic subtypes may have a better response to KDs compared to the other three subtypes. We preliminarily confirmed the idea by literature review and further performed a proof-of-concept experiment to validate the predictive value of the metabolic subtype in liver cancer xenografts.

Conclusions

Our findings identified a metabolic subtype based on glycolysis and KBM that may serve as a promising biomarker to predict the clinical outcomes and therapeutic responses to KDT.

Sulforaphane Causes Cell Cycle Arrest and Apoptosis in Human Glioblastoma U87MG and U373MG Cell Lines under Hypoxic Conditions

Glioblastoma multiforme (GBM) is the most prevalent and aggressive primary brain tumor. The median survival rate from diagnosis ranges from 15 to 17 months because the tumor is resistant to most therapeutic strategies. GBM exhibits microvascular hyperplasia and pronounced necrosis triggered by hypoxia. Sulforaphane (SFN), an isothiocyanate derived from cruciferous vegetables, has already demonstrated the ability to inhibit cell proliferation, by provoking cell cycle arrest, and leading to apoptosis in many cell lines. In this study, we investigated the antineoplastic effects of SFN [20-80 μM for 48 h] in GBM cells under normoxic and hypoxic conditions. Cell viability assays, flow cytometry, and Western blot results revealed that SFN could induce apoptosis of GBM cells in a dose-dependent manner, under both conditions. In particular, SFN significantly induced caspase 3/7 activation and DNA fragmentation. Moreover, our results demonstrated that SFN suppressed GBM cells proliferation by arresting the cell cycle at the S-phase, also under hypoxic condition, and that these effects may be due in part to its ability to induce oxidative stress by reducing glutathione levels and to increase the phosphorylation of extracellular signal-regulated kinases (ERKs). Overall, we hypothesized that SFN treatment might serve as a potential therapeutic strategy, alone or in combination, against GBM.

Metformin and sodium dichloroacetate effects on proliferation, apoptosis, and metabolic activity tested alone and in combination in a canine prostate and a bladder cancer cell line

An important approach in tumor therapy is combining substances with different action mechanisms aiming to enhance the antineoplastic effect, decrease the therapeutic dosage, and avoid resistance mechanisms. Moreover, evaluating compounds already approved for the treatment of non-neoplastic diseases is promising for new antineoplastic therapies. Sodium dichloroacetate (DCA) reactivates oxidative phosphorylation in the cancer cell mitochondria, reducing apoptosis resistance in cancer cells. Furthermore, metformin inhibits the proliferation of tumor cells and CD133+ cancer -stem-like cells. In the present study, we evaluated the independent and synergistic effect of metformin and DCA on the metabolic activity, cell proliferation, and apoptosis of a canine prostate adenocarcinoma (Adcarc1258) and a transitional cell carcinoma cell line (TCC1506) in comparison to a primary canine fibroblast culture. Determining metformin uptake in tumor cells was performed by quantitative HPLC. Depending on the dosage, metformin as a single agent inhibited the metabolic activity and cell proliferation of the tumor cells, showing only minor effects on the fibroblasts. Furthermore, 1 mM metformin increased apoptosis over 96 h in the tumor cell lines but not in fibroblasts. Additionally, metformin uptake into the tumor cells in vitro was measurable by quantitative HPLC. Synergistic effects for the combination therapy were observed in both neoplastic cell lines as well as in the fibroblasts. Based on these results, metformin might be a promising therapeutic agent for canine urogenital tumors. Further studies on kinetics, toxicology, bioavailability, and application of metformin in dogs are necessary.

Multiple interactions between melatonin and non-coding RNAs in cancer biology

The melatonin hormone secreted by the pineal gland is involved in physiological functions such as growth and maturation, circadian cycles, and biological activities including antioxidants, anti-tumor, and anti-ischemia. Melatonin not only interacts with proteins but also has functional effects on regulatory RNAs such as long non-coding RNAs (lncRNAs) and microRNAs (miRNAs). In this study, we overview various physiological and pathological conditions affecting melatonin through lncRNA and miRNA. The information compiled herein will serve as a solid foundation to formulate ideas for future mechanistic studies on melatonin. It will also provide a chance to more clarify the emerging functions of the non-coding transcriptome.

Biochanin A Inhibits Glioblastoma Growth via Restricting Glycolysis and Mitochondrial Oxidative Phosphorylation

Abnormal metabolism serves a critical role in glioblastoma (GBM). Biochanin A (BCA), a flavonoid phenolic compound found in edible and herbal plants, has antioxidative and antitumor activities. However, it remains unclear whether BCA has an effect on energy metabolism. The aim of the present study was to evaluate the anticancer effects and molecular mechanism of the effect of BCA on energy metabolism. We observed that BCA inhibited the growth of U251 cells by the mitochondria-mediated intrinsic apoptotic pathway. BCA treatment reduced metabolic function, repressed mitochondrial membrane potential, and increased the production of reactive oxygen species (ROS) in GBM. In addition, we found that BCA decreased aerobic glycolysis by inactivation of the AKT/mTOR pathway. Taken together, the results demonstrate that treatment with BCA inhibited the proliferation of GBM by regulating metabolic reprogramming.

The Ph paradigm in cancer

Malignant tissues show a peculiar feature regarding pH: while normal tissues have a higher extracellular pH than intracellular pH, in cancer is exactly the opposite. This phenomenon is called the inversion of the pH gradient and is now considered a hallmark of malignancy. For some time, this inverted pH gradient was believed to be a secondary effect of cancer. Now, it is becoming clear that pH inversion is not an innocent consequence, but a key player in the etiopathogenesis of cancer. Therefore, addressing this issue as part of an integral treatment of neoplasia should be a necessary step for improving cancer patients' outcomes. However, the knowledge acquired in this regard through basic research has not reached bedside treatments. The most striking fact is that there are repurposed drugs and nutraceuticals with low or no toxicity that can modify the pH gradient inversion. However, these drugs have not even been tested in cancer treatment.

Role of long noncoding RNA taurine-upregulated gene 1 in cancers

Long non-coding RNAs (lncRNAs) are a group of non-protein coding RNAs with a length of more than 200 bp. The lncRNA taurine up-regulated gene 1 (TUG1) is abnormally expressed in many human malignant cancers, where it acts as a competitive endogenous RNA (ceRNA), regulating gene expression by specifically sponging its corresponding microRNAs. In the present review, we summarised the current understanding of the role of lncRNA TUG1 in cancer cell proliferation, metastasis, angiogenesis, chemotherapeutic drug resistance, radiosensitivity, cell regulation, and cell glycolysis, as well as highlighting its potential application as a clinical biomarker or therapeutic target for malignant cancer. This review provides the basis for new research directions for lncRNA TUG1 in cancer prevention, diagnosis, and treatment.

The Study on the Pathogenesis of Pediatric Lymphoma Based on the Combination of Pseudotargeted and Targeted Metabolomics

Pediatric lymphoma is a kind of malignant tumor with high mortality. The complexity of pediatric lymphoma shows a great challenge for effective diagnosis and treatment. In order to meet the challenge, the combination of pseudotargeted and targeted metabolomics was used to analyze the serum metabolites in pediatric lymphoma patients and healthy controls for discovering the metabolites related to pediatric lymphoma. The serum samples were obtained from the treatment group (n = 43), the control group (n = 26), and the patients group (n = 18). A total of 17 serum metabolites, including carnitine, leucine, creatine, urea, (6Z,9Z,12Z)-octadecatrienoic acid, linoleate, octadecenoic acid, L-palmitoylcarnitine, hexadecanoic acid, tetradecanoic acid, (9Z)-hexadecenoic acid, uric acid, glucose, 1-methylnicotinamide, hypoxanthine, L-glutamine, and taurine, were found to be related to pediatric lymphoma. They could provide a scientific diagnostic basis and therapeutic target for pediatric lymphoma and elucidate the mechanism of pediatric lymphoma.

Emerging Moonlighting Functions of the Branched-Chain Aminotransferase Proteins

Significance: Unique to the branched-chain aminotransferase (BCAT) proteins is their redox-active CXXC motif. Subjected to post-translational modification by reactive oxygen species and reactive nitrogen species, these proteins have the potential to adopt numerous cellular roles, which may be fundamental to their role in oncogenesis and neurodegenerative diseases. An understanding of the interplay of the redox regulation of BCAT with important cell signaling mechanisms will identify new targets for future therapeutics. Recent Advances: The BCAT proteins have been assigned novel thiol oxidoreductase activity that can accelerate the refolding of proteins, in particular when S-glutathionylated, supporting a chaperone role for BCAT in protein folding. Other metabolic proteins were also shown to have peroxide-mediated redox associations with BCAT, indicating that the cellular function of BCAT is more diverse. Critical Issues: While the role of branched-chain amino acid metabolism and its metabolites has dominated aspects of cancer research, less is known about the role of BCAT. The importance of the CXXC motif in regulating the BCAT activity under hypoxic conditions, a characteristic of tumors, has not been addressed. Understanding how these proteins operate under various cellular redox conditions will become important, in particular with respect to their moonlighting roles. Future Directions: Advances in the quantification of thiols, their measurement, and the manipulation of metabolons that rely on redox-based interactions should accelerate the investigation of the cellular role of moonlighting proteins such as BCAT. Given the importance of cross talk between signaling pathways, research should focus more on these "housekeeping" proteins paying attention to their wider application. Antioxid. Redox Signal. 34, 1048-1067.

The Role of NRF2/KEAP1 Signaling Pathway in Cancer Metabolism

The nuclear factor-erythroid 2 p45-related factor 2 (NRF2, also called Nfe2l2) and its cytoplasmic repressor, Kelch-like ECH-associated protein 1 (KEAP1), are major regulators of redox homeostasis controlling a multiple of genes for detoxification and cytoprotective enzymes. The NRF2/KEAP1 pathway is a fundamental signaling cascade responsible for the resistance of metabolic, oxidative stress, inflammation, and anticancer effects. Interestingly, a recent accumulation of evidence has indicated that NRF2 exhibits an aberrant activation in cancer. Evidence has shown that the NRF2/KEAP1 signaling pathway is associated with the proliferation of cancer cells and tumerigenesis through metabolic reprogramming. In this review, we provide an overview of the regulatory molecular mechanism of the NRF2/KEAP1 pathway against metabolic reprogramming in cancer, suggesting that the regulation of NRF2/KEAP1 axis might approach as a novel therapeutic strategy for cancers.

The role of S-nitrosylation of PFKM in regulation of glycolysis in ovarian cancer cells

One of the malignant transformation hallmarks is metabolism reprogramming, which plays a critical role in the biosynthetic needs of unchecked proliferation, abrogating cell death programs, and immunologic escape. However, the mechanism of the metabolic switch is not fully understood. Here, we found that the S-nitrosoproteomic profile of endogenous nitrogen oxide in ovarian cancer cells targeted multiple components in metabolism processes. Phosphofructokinase (PFKM), one of the most important regulatory enzymes of glycolysis, was S-nitrosylated by nitric oxide synthase NOS1 at Cys351. S-nitrosylation at Cys351 stabilized the tetramer of PFKM, leading to resist negative feedback of downstream metabolic intermediates. The PFKM-C351S mutation decreased the proliferation rate of cultured cancer cells, and reduced tumor growth and metastasis in the mouse xenograft model. These findings indicated that S-nitrosylation at Cys351 of PFKM by NOS1 contributes to the metabolic reprogramming of ovarian cancer cells, highlighting a critical role of endogenous nitrogen oxide on metabolism regulations in tumor progression.

Prognostic value of tumor metabolic imaging phenotype by FDG PET radiomics in HNSCC

OBJECTIVE

Tumor metabolic phenotype can be assessed with integrated image pattern analysis of ¹⁸F-fluoro-deoxy-glucose (FDG) Positron Emission Tomography/Computed Tomography (PET/CT), called radiomics. This study was performed to assess the prognostic value of radiomics PET parameters in head and neck squamous cell carcinoma (HNSCC) patients.

METHODS

¹⁸F-fluoro-deoxy-glucose (FDG) PET/CT data of 215 patients from HNSCC collection free database in The Cancer Imaging Archive (TCIA), and 122 patients in Seoul St. Mary's Hospital with baseline FDG PET/CT for locally advanced HNSCC were reviewed. Data from TCIA database were used as a training cohort, and data from Seoul St. Mary's Hospital as a validation cohort. With the training cohort, primary tumors were segmented by Nestles' adaptive thresholding method. Segmental tumors in PET images were preprocessed using relative resampling of 64 bins. Forty-two PET parameters, including conventional parameters and texture parameters, were measured. Binary groups of homogeneous imaging phenotypes, clustered by K-means method, were compared for overall survival (OS) and disease-free survival (DFS) by log-rank test. Selected individual radiomics parameters were tested along with clinical factors, including age and sex, by Cox-regression test for OS and DFS, and the significant parameters were tested with multivariate analysis. Significant parameters on multivariate analysis were again tested with multivariate analysis in the validation cohort.

RESULTS

A total of 119 patients, 70 from training, and 49 from validation cohort, were included in the study. The median follow-up period was 62 and 52 months for the training and the validation cohort, respectively. In the training cohort. binary groups with different metabolic radiomics phenotypes showed significant difference in OS (p = 0.036), and borderline difference in DFS (p = 0.086). Gray-Level Non-Uniformity for zone (GLNU_GLZLM) was the most significant prognostic factor for both OS (hazard ratio [HR] 3.1, 95% confidence interval [CI] 1.4-7.3, p = 0.008) and DFS (HR 4.5, CI 1.3-16, p = 0.020). Multivariate analysis revealed GLNU_GLZLM as an independent prognostic factor for OS (HR 3.7, 95% CI 1.1-7.5, p = 0.032). GLNU_GLZLM remained as an independent prognostic factor in the validation cohort (HR 14.8. 95% CI 3.3-66, p < 0.001).

CONCLUSIONS

Baseline FDG PET radiomics contain risk information for survival prognosis in HNSCC patients. The metabolic heterogeneity parameter, GLNU_GLZLM, may assist clinicians in patient risk assessment as a feasible prognostic factor.

PDK4 promotes vascular calcification by interfering with autophagic activity and metabolic reprogramming

Pyruvate dehydrogenase kinase 4 (PDK4) is an important mitochondrial matrix enzyme in cellular energy regulation. Previous studies suggested that PDK4 is increased in the calcified vessels of patients with atherosclerosis and is closely associated with mitochondrial function, but the precise regulatory mechanisms remain largely unknown. This study aims to investigate the role of PDK4 in vascular calcification and the molecular mechanisms involved. Using a variety of complementary techniques, we found impaired autophagic activity in the process of vascular smooth muscle cells (VSMCs) calcification, whereas knocking down PDK4 had the opposite effect. PDK4 drives the metabolic reprogramming of VSMCs towards a Warburg effect, and the inhibition of PDK4 abrogates VSMCs calcification. Mechanistically, PDK4 disturbs the integrity of the mitochondria-associated endoplasmic reticulum membrane, concomitantly impairing mitochondrial respiratory capacity, which contributes to a decrease in lysosomal degradation by inhibiting the V-ATPase and lactate dehydrogenase B interaction. PDK4 also inhibits the nuclear translocation of the transcription factor EB, thus inhibiting lysosomal function. These changes result in the interruption of autophagic flux, which accelerates calcium deposition in VSMCs. In addition, glycolysis serves as a metabolic adaptation to improve VSMCs oxidative stress resistance, whereas inhibition of glycolysis by 2-deoxy-D-glucose induces the apoptosis of VSMCs and increases the calcium deposition in VSMCs. Our results suggest that PDK4 plays a key role in vascular calcification through autophagy inhibition and metabolic reprogramming.

Non-coding RNAs: the new central dogma of cancer biology

The central dogma of molecular biology states that the functions of RNA revolve around protein translation. Until the last decade, most researches were geared towards characterization of RNAs as intermediaries in protein translation, namely, messenger RNAs (mRNAs) as temporary copies of genetic information, ribosomal RNAs (rRNAs) as a main component of ribosome, or translators of codon sequence (tRNAs). The statistical reality, however, is that these processes account for less than 2% of the genome, and insufficiently explain the functionality of 98% of transcribed RNAs. Recent discoveries have unveiled thousands of unique non-coding RNAs (ncRNAs) and shifted the perception of them from being "junk" transcriptional products to "yet to be elucidated"-and potentially monumentally important-RNAs. Most ncRNAs are now known as key regulators in various networks in which they could lead to specific cellular responses and fates. In major cancers, ncRNAs have been identified as both oncogenic drivers and tumor suppressors, indicating a complex regulatory network among these ncRNAs. Herein, we provide a comprehensive review of the various ncRNAs and their functional roles in cancer, and the pre-clinical and clinical development of ncRNA-based therapeutics. A deeper understanding of ncRNAs could facilitate better design of personalized therapeutics.

The hallmarks of cancer are also the hallmarks of wound healing

The Hanahan and Weinberg "hallmarks of cancer" papers provide a useful structure for considering the various mechanisms driving cancer progression, and the same might be useful for wound healing. In this Review, we highlight how tissue repair and cancer share cellular and molecular processes that are regulated in a wound but misregulated in cancer. From sustained proliferative signaling and the activation of invasion and angiogenesis to the promoting role of inflammation, there are many obvious parallels through which one process can inform the other. For some hallmarks, the parallels are more obscure. We propose some new prospective hallmarks that might apply to both cancer and wound healing and discuss how wounding, as in biopsy and surgery, might positively or negatively influence cancer in the clinic.