SLMP53-1 Inhibits Tumor Cell Growth through Regulation of Glucose Metabolism and Angiogenesis in a P53-Dependent Manner

HIF1A transcriptional regulation of COX4I2 impacts angiogenesis in pheochromocytoma

BACKGROUND

Pheochromocytoma (PCC) is a rare neuroendocrine tumor. Angiogenesis is primary contributing factor for tumorigenesis. Cytochrome c oxidase 4I2 (COX4I2) has been confirmed to take part in the progression of cancer. Hypoxia-inducible factor 1A (HIF1A) is the main regulatory factor for the steady-state response of hypoxia, involved in metabolism and angiogenesis. In this study, we intended to explore the functions of COX4I2 in PCC and the effect mechanism between HIF1A and COX4I2.

MATERIALS AND METHODS

The RNA-sequencing and immunohistochemistry tested COX4I2 expression in highly vascular PCC. Small interfering RNA (siRNA) was used to reduce the mRNA expression of COX4I2, and a small molecule inhibitor was utilized to reduce the protein expression of HIF1A. Culturing cells in 1% O2environment was performed to activate HIF1A. Western blot was applied to quantify the expression of target genes at the protein levels. The supernatant from PCC cells and fibroblasts acted as the conditioned medium. We conducted the tube formation and transwell assays in human vascular endothelial cells (HUVECs) to determine angiogenesis, the binding of COX4I2 promoter and HIF1A was evaluated by the dual luciferase reporter assay.

RESULTS

COX4I2 had been rigorously shown to be overexpressed in highly vascular PCC. Knockdown of COX4I2 in PCC cells (MPC) did not significantly impact angiogenesis, while knockdown of COX4I2 in fibroblast (3T3) notably inhibited angiogenesis. RNA sequencing suggested that the expression of 11 vascular markers, such as CD34 and angiogenesis associated pathways in 3T3, decreased with knockdown of COX4I2. HIF1A had been shown to enhance the mRNA expression of COX4I2 through transcriptional regulation. Activation and inhibition of HIF1A resulted in upregulation and downregulation of COX4I2, respectively. The HIF1A inhibitor demonstrated a reduction in angiogenesis.

CONCLUSION

COX4I2 is overexpressed in highly vascular PCC and contributes to angiogenesis in fibroblasts. Mechanistically, HIF1A transcriptional regulation enhances COX4I2 and its effects on angiogenesis in PCC. COX4I2 might serve as a vascular marker and represent a potential target for vascular therapy.

Metabolomics analysis of amino acid and fatty acids in colorectal cancer patients based on tandem mass spectrometry

Metabolic differences between colorectal cancer (CRC) and NI (NI) play an important role in early diagnoses and in-time treatments. We investigated the metabolic alterations between CRC patients and NI, and identified some potential biomarkers, and these biomarkers might be used as indicators for diagnosis of CRC. In this study, there were 79 NI, 50 CRC I patients, 52 CRC II patients, 56 CRC III patients, and 52 CRC IV patients. MS-MS was used to measure the metabolic alterations. Univariate and multivariate data analysis and metabolic pathway analysis were applied to analyze metabolic data and determine differential metabolites. These indicators revealed that amino acid and fatty acids could separate these groups. Several metabolites indicated an excellent variables capability in the separation of CRC patients and NI. Ornithine, arginine, octadecanoyl carnitine, palmitoyl carnitine, adipoyl carnitine, and butyryl carnitine/propanoyl carnitine were selected to distinguish the CRC patients and NI. And methionine and propanoyl carnitine, were directly linked to different stages of CRC. Receiver operating characteristics curves and variables importance in projection both represented an excellent performance of these metabolites. In conclusion, we assessed the difference between CRC patients and NI, which supports guidelines for an early diagnosis and effective treatment.

HOXD9 contributes to the Warburg effect and tumor metastasis in non-small cell lung cancer via transcriptional activation of PFKFB3

Warburg effect is associated with the progression of various tumors, leading to the development of drugs targeting the phenomenon. PFKFB3 is an isoform of 6-phosphofructo-2-kinase (PFK2) that modulates the Warburg effect and has been implicated in most common types of cancer, including non-small cell lung cancer (NSCLC). However, the mechanisms underlying the upstream regulation of PFKFB3 in NSCLC remain poorly understood. This study reported that the transcription factor HOXD9 is upregulated in NSCLC patient samples relative to adjacent normal tissue. Elevated HOXD9 levels are primarily associated with poor prognosis in patients with NSCLC. Functionally, HOXD9 knockdown impaired the metastatic capacity of NSCLC cells, whereas its over-expression accelerated the metastasis and invasion of NSCLC cells in an orthotopic tumor mouse model. In addition, HOXD9 promoted metastasis by increasing cellular glycolysis. Further mechanistic studies revealed that HOXD9 directly binds to the promoter region of PFKFB3 to enhance its transcription. The recovery assay confirmed that the capability of HOXD9 to promote NSCLC cells metastasis was significantly weakened upon PFKFB3 inhibition. These data suggest that HOXD9 may exert as a novel biomarker in NSCLC, indicating that blocking the HOXD9/PFKFB3 axis may be a potential therapeutic strategy for NSCLC treatment.

Exosomal miR-211-5p regulates glucose metabolism, pyroptosis, and immune microenvironment of melanoma through GNA15

Despite the unprecedented advancement of cancer treatment, the prognosis for patients with metastatic stage of cancer remains poor. The challenge that underlines this clinical dilemma is the complexity of metastasis. The conventional experiment-driven discovery approaches (the "wet lab") yield overly simplified one-to-one mechanistic relationships that are inept of elucidating the complexity of metastasis. Metastasis research also suffers from the knowledge and skill deficiency of the individual investigators. The importance of the present study is the demonstration that the "dry-lab-driven discovery and wet-lab validation" approach can improve the efficiency of studying complex biological behaviors, and can yield more reliable, objective and comprehensive mechanistic findings that are have clinical significance. Specifically, we applied this approach to study the mechanisms that underline the involvement of exosomal miRNAs in transferring the metastatic capability between heterogenous melanoma cancer cells. We show that the highly metastatic melanoma tumor cells (POL) can transfer their metastatic competency to the low-metastatic melanoma tumor cells (OL) by exosomal miR-211-5p. The oncogenic activity of miR-211-5p is mediated by the target gene guanine nucleotide-binding protein subunit alpha-15 (GNA15) through modifying the immune function of the tumor microenvironment extrinsically; as well as through inhibiting pyroptosis and augmenting glycolysis within OL cells intrinsically. In addition, we show that exosomal sorting of miR-211-5p is like selective and is subjected to regulation by a transcriptional feedback loop between miR-211-5p and zinc finger FYVE-type containing 26 (ZFYVE26). Furthermore, the "8-genes pyroptosis Risk model" derived from LASSO regression analysis was verified as an independent prognostic factor for melanoma.

Biological and Clinical Impacts of Glucose Metabolism in Pancreatic Ductal Adenocarcinoma

Pancreatic ductal adenocarcinoma (PDAC) is a lethal cancer type as it is prone to metastases and is difficult to diagnose at an early stage. Despite advances in molecular detection, its clinical prognosis remains poor and it is expected to become the second leading cause of cancer-related deaths. Approximately 85% of patients develop glucose metabolism disorders, most commonly diabetes mellitus, within three years prior to their pancreatic cancer diagnosis. Diabetes, or glucose metabolism disorders related to PDAC, are typically associated with insulin resistance, and beta cell damage, among other factors. From the perspective of molecular regulatory mechanisms, glucose metabolism disorders are closely related to PDAC initiation and development and to late invasion and metastasis. In particular, abnormal glucose metabolism impacts the nutritional status and prognosis of patients with PDAC. Meanwhile, preliminary research has shown that metformin and statins are effective for the prevention or treatment of malignancies; however, no such effect has been shown in clinical trials. Hence, the causes underlying these conflicting results require further exploration. This review focuses on the clinical significance of glucose metabolism disorders in PDAC and the mechanisms behind this relationship, while also summarizing therapeutic approaches that target glycolysis.

Quantitative proteomics identified a novel invasion biomarker associated with EMT in pituitary adenomas

BACKGROUND

Complete resection of invasive pituitary adenoma is usually difficult, resulting in a high recurrence rate. Therefore, it is needed to find potential diagnostic markers and therapeutic targets for invasive pituitary adenoma.

METHODS

We collected samples from patients with invasive and non-invasive pituitary adenomas from Beijing Tiantan Hospital for protein extraction and quantitative analysis. We identified differential proteins (DEPs) by differential analysis of the two groups. The intersection of differential proteins related to invasion and epithelial-mesenchymal transition (EMT) in the GeneCards database was identified as EMT-DEPs. The protein network of EMT-DEPs was analyzed using the STRING database and Cytoscape software, and the hub EMT-DEPs were obtained by the MCC algorithm of the cytoHubba plugin. Correlation analysis was used to obtain the interpairing proteins among EMT-DEPs, and core EMT-DEPs were identified based on the number of paired proteins. The Venn program was used to identify the intersection of hub EMT-DEPs and core EMT-DEPs as key EMT-DEPs. Finally, a series of analyses plus experiments were used to verify the correlation of the target protein with invasion and EMT in pituitary adenoma.

RESULTS

Quantitative comparison of proteins between invasive and non-invasive pituitary adenomas indicated 833 differential proteins. The overlaps of EMT-related proteins and differential proteins consisted of 46 EMT-DEPs. There were 6 intersections between the hub EMT-DEPs and core EMT-DEPs. Using quantitative protein data and GSE169498 chip, we found that solute carrier family 2 member 1 (SLC2A1) was our target protein. SLC2A1 was significantly correlated with the invasiveness of pituitary adenoma, and the ROC curve was satisfactory. The functions and pathways of SLC2A1 and paired protein enrichment were closely linked to the EMT. Consistently, SLC2A1 expression was significantly and positively correlated with the expression of classical markers of EMT. The final experiment revealed that SLC2A1 was significantly upregulated in invasive pituitary adenoma.

CONCLUSION

SLC2A1 is significantly upregulated in invasive pituitary adenoma with satisfactory predictive value. It may regulate EMT. It may be a potential diagnostic marker for invasive pituitary adenoma.

Metabolic Reprogramming in Cancer Cells: Emerging Molecular Mechanisms and Novel Therapeutic Approaches

The constant changes in cancer cell bioenergetics are widely known as metabolic reprogramming. Reprogramming is a process mediated by multiple factors, including oncogenes, growth factors, hypoxia-induced factors, and the loss of suppressor gene function, which support malignant transformation and tumor development in addition to cell heterogeneity. Consequently, this hallmark promotes resistance to conventional anti-tumor therapies by adapting to the drastic changes in the nutrient microenvironment that these therapies entail. Therefore, it represents a revolutionary landscape during cancer progression that could be useful for developing new and improved therapeutic strategies targeting alterations in cancer cell metabolism, such as the deregulated mTOR and PI3K pathways. Understanding the complex interactions of the underlying mechanisms of metabolic reprogramming during cancer initiation and progression is an active study field. Recently, novel approaches are being used to effectively battle and eliminate malignant cells. These include biguanides, mTOR inhibitors, glutaminase inhibition, and ion channels as drug targets. This review aims to provide a general overview of metabolic reprogramming, summarise recent progress in this field, and emphasize its use as an effective therapeutic target against cancer.

The role of PFKFB3 in maintaining colorectal cancer cell proliferation and stemness

Since generally confronting with the hypoxic and stressful microenvironment, cancer cells alter their glucose metabolism pattern to glycolysis to sustain the continuous proliferation and vigorous biological activities. Bifunctional 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase (PFK-2/FBPase-2) isoform 3 (PFKFB3) functions as an effectively modulator of glycolysis and also participates in regulating angiogenesis, cell death and cell stemness. Meanwhile, PFKFB3 is highly expressed in a variety of cancer cells, and can be activated by several regulatory factors, such as hypoxia, inflammation and cellular signals. In colorectal cancer (CRC) cells, PFKFB3 not only has the property of high expression, but also probably relate to inflammation-cancer transformation. Recent studies indicate that PFKFB3 is involved in chemoradiotherapy resistance as well, such as breast cancer, endometrial cancer and CRC. Cancer stem cells (CSCs) are self-renewable cell types that contribute to oncogenesis, metastasis and relapse. Several studies indicate that CSCs utilize glycolysis to fulfill their energetic and biosynthetic demands in order to maintain rapid proliferation and adapt to the tumor microenvironment changes. In addition, elevated PFKFB3 has been reported to correlate with self-renewal and metastatic outgrowth in numerous kinds of CSCs. This review summarizes our current understanding of PFKFB3 roles in modulating cancer metabolism to maintain cell proliferation and stemness, and discusses its feasibility as a potential target for the discovery of antineoplastic agents, especially in CRC.

ceRNA regulatory network of FIH inhibitor as a radioprotector for gastrointestinal toxicity by activating the HIF-1 pathway

Given the relentless renewal ability of intestinal crypt-base stem cells, small intestine in the gastrointestinal (GI) tract is more vulnerable to radiation-induced disruption. Through promoting epithelial integrity and reducing intracellular reactive oxygen species (ROS) levels, hypoxia-inducible factors (HIFs) have been proved to exhibit radioprotective effects in the GI tract. Therefore, enhancing stability or transcriptional activity of HIFs might be a therapeutic strategy for developing radioprotectors. Factor inhibiting HIF (FIH or HIF-1AN) can hamper transcriptional capacity of HIF-1α via interacting with Asn803 in its C-terminal domain. Previously, we discovered promoting HIF-1α transcriptional activity in vitro by FIH inhibitor-N-oxalyl-D-phenylalanine (NOFD) exerts radioprotection on cells. However, the radioprotective effect of FIH inhibitor on the GI tract and its competing endogenous RNA (ceRNA) regulatory network from the FIH/HIF axis has never been addressed. Here we verified radioprotection of NOFD for the GI tract by an animal model and performed whole-transcriptome analysis to fully elucidate the radioprotective mechanism from the FIH/HIF axis against GI syndrome. We identified two novel circular RNAs (circRNAs) (circRNA_2909 and circRNA_0323) and two long non-coding RNAs (lncRNAs) (NONMMUT140549.1 and NONMMUT148249.1) that promote expression of HIF1A and NOS2 in the HIF-1 pathway by sponging microRNAs (miRNAs), especially mmu-miR-92a-1-5p. The de-repression of HIF-1α transcriptional capacity by inhibiting FIH proteomic activity suggests a new therapeutic strategy in alleviating radiation-induced GI syndrome.

Downregulation of GLUT3 impairs STYK1/NOK-mediated metabolic reprogramming and proliferation in NIH-3T3 cells

Serine threonine tyrosine kinase 1 (STYK1)/novel oncogene with kinase domain (NOK) has been demonstrated to promote cell carcinogenesis and tumorigenesis, as well as to strengthen cellular aerobic glycolysis, which is considered to be a defining hallmark of cancer. As the carriers of glucose into cells, glucose transporters (GLUTs) are important participants in cellular glucose metabolism and even tumorigenesis. However, to the best of our knowledge, the role of GLUTs in biological events caused by STYK1/NOK has not yet been reported. The present study assessed GLUT3 as a key transporter, and glucose consumption and lactate production assays revealed that downregulation of GLUT3 impaired STYK1/NOK-induced augmented glucose uptake and lactate production, and RT-qPCR and western blotting confirmed that GLUT3 knockdown attenuated the STYK1/NOK-induced increase in the expression levels of key enzymes implicated in glycolysis. Furthermore, MTT and Transwell assays demonstrated that STYK1/NOK-triggered cell proliferation and migration were also markedly decreased following knockdown of GLUT3. To the best of our knowledge, the present study is the first to demonstrate that GLUT3 serves a prominent role in STYK1/NOK-driven aerobic glycolysis and cell proliferation characteristics. These findings may provide a clue for the investigation of the oncogenic activity of STYK1/NOK and for the identification of potential tumor therapy targets associated with GLUT3.

Monocarboxylate Transporters 1 and 4 and MTCO1 in Gastric Cancer

Simple Summary

The expression of monocarboxylate transporters (MCTs) are reported in a variety of cancers and suggested as a therapeutic target for cancer treatment. However, previous study results in gastric cancer are contradictory. In this study, we evaluated the expression of MCT1, MCT4, and Mitochondrial cytochrome c oxidase (MTCO1) and their association with clinicopathological parameters and prognostic significance in a cohort of 568 surgically treated gastric cancer patients. The results suggest that monocarboxylate transporters and MTCO1 are associated with gastric cancer progression but have no independent prognostic relevance.

Abstract

Background: Monocarboxylate transporters (MCTs) appear to play an important role in tumor development and aggressiveness. The present study aimed to evaluate associations between cytoplasmic MCT1, MCT4, and mitochondrial cytochrome c oxidase (MTCO1) expression and clinicopathological variables or survival in gastric cancer. Material and methods: A total of 568 gastric adenocarcinoma patients were included in this retrospective cohort study. Protein expressions were detected by immunohistochemical staining. The patients were divided into low expression and high expression groups by median value. The Chi-squared test was used to compare categorical variables. The T-test was used to compare continuous variables. Expressions were analyzed in relation to 5-year survival and overall survival. Cox regression provided HRs and 95% CIs, adjusted for confounders. Results: High cytoplasmic MCT1 expression was associated statistically significantly with higher T-class (p = 0.020). High cytoplasmic MCT4 expression was associated statistically significantly with positive lymph node status (p = 0.005) and was more common in Lauren’s intestinal type (p < 0.001). Low cytoplasmic MTCO1 expression was associated statistically significantly with positive distant metastases (p = 0.030), and high cytoplasmic MTCO1 expression was associated more often with intestinal type (p = 0.044). However, MCT1, MCT4, and MTCO1 were not associated with survival. Conclusions: Monocarboxylate receptors seem to be associated with gastric cancer progression but have no independent prognostic relevance.

MUC16 promotes EOC proliferation by regulating GLUT1 expression

As a common malignancy in females with a higher incidence rate, epithelial ovarian cancer (EOC) is a heterogeneous disease with complexity and diversity in histology and therapeutic response. Although great progress has been made in diagnosis and therapeutic strategies, novel therapeutic strategies are required to improve survival. Although the promoting effect of mucin 16 (MUC16) on tumour progression has been reported, the potential mechanisms remain unclear. In our study, we reported that overexpression of MUC16 was significantly related to cell proliferation and disease progression in EOC. Results from clinical specimen analysis and cell experiment support this conclusion. Patients with a high MUC16 expression usually had a worse prognosis that those with a low expression. Cell proliferation ability was significantly decreased in EOC cell lines when the knockdown of MUC16. Further study shows that the function of MUC16 in cell proliferation is based on the regulation of glucose transporter 1 (GLUT1) expression. MUC16 can control glucose uptake by regulating GLUT1 in EOC cells, thereby promoting glycogen synthesis, so that tumour cells produce more energy for proliferation. This conclusion is based on two findings. First, the significant correlation between MUC16 and GLUT1 was verified by clinical specimen and TCGA data analysis. Then, alteration of MUC16 expression levels can affect the expression of GLUT1 and glucose uptake was also verified. Finally, this conclusion is further verified in vivo by tumour‐bearing mice model. To summarize, our results suggest that MUC16 promotes EOC proliferation and disease progression by regulating GLUT1 expression.

Gomisin J inhibits the glioma progression by inducing apoptosis and reducing HKII-regulated glycolysis

Glioma is a leading cause of central nervous system malignant tumor-associated deaths in the world. However, the molecular mechanisms for glioma progression are still unclear, lacking effective therapeutic strategies. Gomisin J (GomJ) is a derivative of lignan compound, and shows regulatory effects on virus, oxidative stress and tumor progression. However, the role of GomJ in the meditation of glioma progression has not been explored. In this study, we found that GomJ markedly reduced the proliferation of glioma cell lines. Mitochondrial apoptosis was highly induced by GomJ, as evidenced by the significantly up-regulated expression of cytoplastic Cyto-c and cleaved Caspase-3. In addition, mitochondrial membrane potential (MMP) and oxidative stress were highly triggered in GomJ-incubated glioma cells, accompanied with the glycolysis suppression. Importantly, we found that GomJ could dramatically reduce the expression of hexokinase II (HKII) in glioma cells. At the same time, the dissociation of HKII from voltage-dependent anion channel (VDAC) in mitochondria was markedly induced by GomJ, contributing to glycolytic repression. The in vivo experiments confirmed that GomJ obviously reduced the growth of glioma with HKII reduction and few side effects. Taken together, these results demonstrated that GomJ could inhibit the proliferation, induce apoptosis and restrain HKII-regulated glycolysis during glioma progression. Herein, GomJ with few toxicity might be served as a potential therapeutic strategy for the treatment of glioma in humans.