High USP6NL Levels in Breast Cancer Sustain Chronic AKT Phosphorylation and GLUT1 Stability Fueling Aerobic Glycolysis

CYP3A5 unexpectedly regulates glucose metabolism through the AKT-TXNIP-GLUT1 axis in pancreatic cancer

CYP3A5 is a cytochrome P450 (CYP) enzyme that metabolizes drugs and contributes to drug resistance in cancer. However, it remains unclear whether CYP3A5 directly influences cancer progression. In this report, we demonstrate that CYP3A5 regulates glucose metabolism in pancreatic ductal adenocarcinoma. Multi-omics analysis showed that CYP3A5 knockdown results in a decrease in various glucose-related metabolites through its effect on glucose transport. A mechanistic study revealed that CYP3A5 enriches the glucose transporter GLUT1 at the plasma membrane by restricting the translation of TXNIP, a negative regulator of GLUT1. Notably, CYP3A5-generated reactive oxygen species were proved to be responsible for attenuating the AKT-4EBP1-TXNIP signaling pathway. CYP3A5 contributes to cell migration by maintaining high glucose uptake in pancreatic cancer. Taken together, our results, for the first time, reveal a role of CYP3A5 in glucose metabolism in pancreatic ductal adenocarcinoma and identify a novel mechanism that is a potential therapeutic target.

Drug resistance mechanisms and treatment strategies mediated by Ubiquitin-Specific Proteases (USPs) in cancers: new directions and therapeutic options

Drug resistance represents a significant obstacle in cancer treatment, underscoring the need for the discovery of novel therapeutic targets. Ubiquitin-specific proteases (USPs), a subclass of deubiquitinating enzymes, play a pivotal role in protein deubiquitination. As scientific research advances, USPs have been recognized as key regulators of drug resistance across a spectrum of treatment modalities, including chemotherapy, targeted therapy, immunotherapy, and radiotherapy. This comprehensive review examines the complex relationship between USPs and drug resistance mechanisms, focusing on specific treatment strategies and highlighting the influence of USPs on DNA damage repair, apoptosis, characteristics of cancer stem cells, immune evasion, and other crucial biological functions. Additionally, the review highlights the potential clinical significance of USP inhibitors as a means to counter drug resistance in cancer treatment. By inhibiting particular USP, cancer cells can become more susceptible to a variety of anti-cancer drugs. The integration of USP inhibitors with current anti-cancer therapies offers a promising strategy to circumvent drug resistance. Therefore, this review emphasizes the importance of USPs as viable therapeutic targets and offers insight into fruitful directions for future research and drug development. Targeting USPs presents an effective method to combat drug resistance across various cancer types, leading to enhanced treatment strategies and better patient outcomes.

Membrane trafficking alterations in breast cancer progression

Breast cancer (BC) is the most common type of cancer in women, and remains one of the major causes of death in women worldwide. It is now well established that alterations in membrane trafficking are implicated in BC progression. Indeed, membrane trafficking pathways regulate BC cell proliferation, migration, invasion, and metastasis. The 22 members of the ADP-ribosylation factor (ARF) and the >60 members of the rat sarcoma (RAS)-related in brain (RAB) families of small GTP-binding proteins (GTPases), which belong to the RAS superfamily, are master regulators of membrane trafficking pathways. ARF-like (ARL) subfamily members are involved in various processes, including vesicle budding and cargo selection. Moreover, ARFs regulate cytoskeleton organization and signal transduction. RABs are key regulators of all steps of membrane trafficking. Interestingly, the activity and/or expression of some of these proteins is found dysregulated in BC. Here, we review how the processes regulated by ARFs and RABs are subverted in BC, including secretion/exocytosis, endocytosis/recycling, autophagy/lysosome trafficking, cytoskeleton dynamics, integrin-mediated signaling, among others. Thus, we provide a comprehensive overview of the roles played by ARF and RAB family members, as well as their regulators in BC progression, aiming to lay the foundation for future research in this field. This research should focus on further dissecting the molecular mechanisms regulated by ARFs and RABs that are subverted in BC, and exploring their use as therapeutic targets or prognostic markers.

Super-enhancer driven SOX2 promotes tumor formation by chromatin re-organization in nasopharyngeal carcinoma

BACKGROUND

Nasopharyngeal carcinoma (NPC) is a malignant head and neck cancer with a high incidence in Southern China and Southeast Asia. Patients with remote metastasis and recurrent NPC have poor prognosis. Thus, a better understanding of NPC pathogenesis may identify novel therapies to address the unmet clinical needs.

METHODS

H3K27ac ChIP-seq and HiChIP was applied to understand the enhancer landscapes and the chromosome interactions. Whole genome sequencing was conducted to analyze the relationship between genomic variations and epigenetic dysregulation. CRISPRi and JQ1 treatment were used to evaluate the transcriptional regulation of SOX2 SEs. Colony formation assay, survival analysis and in vivo subcutaneous patient-derived xenograft assays were applied to explore the function and clinical relevance of SOX2 in NPC.

FINDINGS

We globally mapped the enhancer landscapes and generated NPC enhancer connectomes, linking NPC specific enhancers and SEs. We found five overlapped genes, including SOX2, among super-enhancer regulated genes, survival related genes and NPC essential genes. The mRNA expression of SOX2 was repressed when applying CRISPRi targeting different SOX2 SEs or JQ1 treatment. Next, we identified a genetic variation (Chr3:181422197, G > A) in SOX2 SE which is correlated with higher expression of SOX2 and poor survival. In addition, SOX2 was highly expressed in NPC and is correlated with short survival in patients with NPC. Knock-down of SOX2 suppressed tumor growth in vitro and in vivo.

INTERPRETATION

Our study demonstrated the super-enhancer landscape with chromosome interactions and identified super-enhancer driven SOX2 promotes tumorigenesis, suggesting that SOX2 is a potential therapeutic target for patients with NPC.

FUNDING

A full list of funding bodies that contributed to this study can be found in the Acknowledgements section.

IGFBP7 Fuels the Glycolytic Metabolism in B-Cell Precursor Acute Lymphoblastic Leukemia by Sustaining Activation of the IGF1R-Akt-GLUT1 Axis

Increased glycolytic metabolism plays an important role in B-cell precursor Acute Lymphoblastic Leukemia (BCP-ALL). We previously showed that IGFBP7 exerts mitogenic and prosuvival effects in ALL by promoting IGF1 receptor (IGF1R) permanence on the cell surface, thus prolonging Akt activation upon IGFs/insulin stimulation. Here, we show that sustained activation of the IGF1R-PI3K-Akt axis concurs with GLUT1 upregulation, which enhances energy metabolism and increases glycolytic metabolism in BCP-ALL. IGFBP7 neutralization with a monoclonal antibody or the pharmacological inhibition of the PI3K-Akt pathway was shown to abrogate this effect, restoring the physiological levels of GLUT1 on the cell surface. The metabolic effect described here may offer an additional mechanistic explanation for the strong negative impact seen in ALL cells in vitro and in vivo after the knockdown or antibody neutralization of IGFBP7, while reinforcing the notion that it is a valid target for future therapeutic interventions.

OBHS Drives Abnormal Glycometabolis Reprogramming via GLUT1 in Breast Cancer

Due to the poor metabolic conditions fomenting the emergence of the Warburg effect (WE) phenotype, abnormal glycometabolism has become a unique and fundamental research topic in the field of tumor biology. Moreover, hyperglycemia and hyperinsulinism are associated with poor outcomes in patients with breast cancer. However, there are a few studies on anticancer drugs targeting glycometabolism in breast cancer. We hypothesized that Oxabicycloheptene sulfonate (OBHS), a class of compounds that function as selective estrogen receptor modulators, may hold potential in a therapy for breast cancer glycometabolism. Here, we evaluated concentrations of glucose, glucose transporters, lactate, 40 metabolic intermediates, and glycolytic enzymes using an enzyme-linked immunosorbent assay, Western blotting, and targeted metabolomic analysis in, in vitro and in vivo breast cancer models. OBHS significantly inhibited the expression of glucose transporter 1 (GLUT1) via PI3K/Akt signaling pathway to suppress breast cancer progression and proliferation. Following an investigation of the modulatory effect of OBHS on breast cancer cells, we found that OBHS suppressed the glucose phosphorylation and oxidative phosphorylation of glycolytic enzymes, leading to the decreased biological synthesis of ATP. This study was novel in highlighting the role of OBHS in the remodeling of tumor glycometabolism in breast cancer, and this is worth further investigation of breast cancer in clinical trials.

Bioinformatics-Based Analysis of Key Genes in Steroid-Induced Osteonecrosis of the Femoral Head That Are Associated with Copper Metabolism

Osteonecrosis of the femoral head (ONFH) is a common disabling disease. Copper has positive effects on cells that regulate bone metabolism. However, the relationship between copper metabolism (CM) and steroid-induced ONFH (SONFH) remains unclear. The GSE123568 dataset was downloaded from the Gene Expression Omnibus. The differentially expressed CM-related SONFH genes (DE-CMR-SONFHGs) were identified via differential analysis and weighted gene coexpression network analysis (WGCNA). Receiver operating characteristic (ROC) analysis was performed for the predictive accuracy of key genes. Targeting drugs and the copper death-related genes (CDRGs) relevant to key genes were investigated. The bioinformatics results were confirmed via quantitative real-time polymerase chain reaction (qRT–PCR) and Western blot (WB) analysis. Two out of 106 DE-CMR-SONFHGs were identified as key genes (PNP and SLC2A1), which had diagnostic value in distinguishing SONFH from control samples and were related to various immune cell infiltrations. Eleven PMP-targeting drugs and five SLC2A1-targeting drugs were identified. The qRT–PCR, as well as WB, results confirmed the downregulation PNP and SLC2A1 and high expression of the CDRGs DLD, PDHB, and MTF1, which are closely related to these two key genes. In conclusion, PNP and SLC2A1 were identified as key genes related to SONFH and may provide insights for SONFH treatment.

Inhibition of ATF4-mediated elevation of both autophagy and AKT/mTOR was involved in antitumorigenic activity of curcumin

Curcumin, a natural hydrophobic polyphenol, carries significant anticancer activity. The protein kinase B (AKT)/the mammalian target of the rapamycin (mTOR) pathway and autophagy are well known to be involved in carcinogenesis, and usually, inhibition of mTOR is the main reason to promote autophagy. In this study, however, autophagy and mTOR were found to be inhibited simultaneously by curcumin treatments, and both of them played an important role in the effect of curcumin on suppressing the growth of A549 cells. Tunicamycin (TM), the activator of Endoplasmic Reticulum (ER) stress, increased both autophagy and AKT/mTOR, while curcumin could significantly decrease TM-induced autophagy and AKT/mTOR. Furthermore, curcumin could inhibit TM-induced aerobic glycolysis in A549 cells, and decrease the level of cycle-related and migration-related proteins. Blocking activating transcription factor 4 (ATF4) by siRNA strongly reduced both the expression of autophagy-related proteins and AKT/mTOR. ChIP assay illustrated that ATF4 protein could bind to the promotor sequence of either ATG4B or AKT1. The transplantation tumor experiment showed that the weight and volume of the transplanted tumors were reduced significantly in the BALB/c mice subcutaneously injected with A549 cells treated with curcumin. Moreover, intranasal administration of curcumin decreased the protein level of autophagy, AKT/mTOR and ER stress in lung tissues of BALB/c mice. Taken together, our results demonstrated that inhibition of ER stress-dependent ATF4-mediated autophagy and AKT/mTOR pathway plays an important role in anticancer effect of curcumin.

Overexpression of miR-181a regulates the Warburg effect in triple-negative breast cancer

OBJECTIVE

Triple-negative breast cancer (TNBC) is highly aggressive and leads to a poor prognosis. microRNA-181a (miR-181a) exhibits strong antineoplastic effects in many types of cancer. In this study, we examine the responses of human miR-181a-transfected TNBC cells and explore the mechanisms underlying the observed effects.

METHODS

A series of cellular assays were conducted using cells from the MDA-MB-231 TNBC line to assess the impact of miR-181a overexpression. The extracellular acidification rate, lactate production and glucose uptake were evaluated as a measure of aerobic glycolysis (i.e. the Warburg effect). The expressions of glycolysis-related gene were analyzed.

RESULTS

Viability, migration and survival of miR-181a-transfected MDA-MB-231 cells were all significantly reduced. miR-181a inhibited glycolysis in TNBC cells by reducing the rates of glucose uptake and lactate production and a substantial downregulation of factors known to contribute to the Warburg effect, including the serine/threonine kinase, AKT3, hypoxia-inducible factor-1α (HIF-1α) and progesterone receptor membrane component 1 (PGRMC1).

CONCLUSION

Our results demonstrate that miR-181a may regulate glycolysis in MDA-MB-231 TNBC cells, potentially via interference with components of the AKT3-HIF-1α and PGRMC1 pathways. These results suggest that miR-181a might be developed as a therapeutic agent for use in antineoplastic regimens directed at TNBC and PGRMC1-overexpressing breast cancers.

Ciliary Neurotrophic Factor Modulates Multiple Downstream Signaling Pathways in Prostate Cancer Inhibiting Cell Invasiveness

BACKGROUND

Prostate cancer (PCa) remains the most common diagnosed tumor and is the second-leading cause of cancer-related death in men. If the cancer is organ-confined it can be treated by various ablative therapies such as RP (radical prostatectomy), RT (radiation therapy), brachytherapy, cryosurgery or HIFU (High-Intensity Focused Ultrasound). However, advanced or metastatic PCa treatment requires systemic therapy involving androgen deprivation, but such patients typically progress to refractory disease designated as castration-resistant prostate cancer (CRPC). Interleukin-6 (IL-6) has been established as a driver of prostate carcinogenesis and tumor progression while less is known about the role of ciliary neurotrophic factor (CNTF), a member of the IL-6 cytokine family in prostate cancer. Moreover, MAPK/ERK, AKT/PI3K and Jak/STAT pathways that regulate proliferative, invasive and glucose-uptake processes in cancer progression are triggered by CNTF.

METHODS

We investigate CNTF and its receptor CNTFRα expressions in human androgen-responsive and castration-resistant prostate cancer (CRPC) by immunohistochemistry. Moreover, we investigated the role of CNTF in proliferative, invasive processes as well as glucose uptake using two cell models mimicking the PCa (LNCaP cell line) and CRPC (22Rv1 cell line).

CONCLUSIONS

Our results showed that CNTF and CNTFRa were expressed in PCa and CRPC tissues and that CNTF has a pivotal role in prostate cancer environment remodeling and as a negative modulator of invasion processes of CRPC cell models.

A combination of novel NSC small molecule inhibitor along with doxorubicin inhibits proliferation of triple-negative breast cancer through metabolic reprogramming

Treatment of patients with triple-negative breast cancer (TNBC) has been challenging due to the absence of well-defined molecular targets and the highly invasive and proliferative nature of TNBC cells. Current treatments against TNBC have shown little promise due to high recurrence rate in patients. Consequently, there is a pressing need for novel and efficacious therapies against TNBC. Here, we report the discovery of a novel small molecule inhibitor (NSC33353) with potent anti-tumor activity against TNBC cells. The anti-proliferative effects of this small molecule inhibitor were determined using 2D and 3D cell proliferation assays. We found that NSC33353 significantly reduces the proliferation of TNBC cells in these assays. Using proteomics, next generation sequencing (NGS), and gene enrichment analysis, we investigated global regulatory pathways affected by this compound in TNBC cells. Proteomics data indicate a significant metabolic reprograming affecting both glycolytic enzymes and energy generation through oxidative phosphorylation. Subsequently, using metabolic (Seahorse) and enzymatic assays, we validated our proteomics and NGS analysis findings. Finally, we showed the inhibitory and anti-tumor effects of this small molecule in vitro and confirmed its inhibitory activity in vivo. Doxorubicin is one of the most effective agents in the treatment of TNBC and resistance to this drug has been a major problem. We show that the combination of NSC33353 and doxorubicin suppresses the growth of TNBC cells synergistically, suggesting that NSC33353 enhances TNBC sensitivity to doxorubicin. In summary, our data indicate that the small molecule inhibitor, NSC33353, exhibits anti-tumor activity in TNBC cells, and works in a synergistic fashion with a well-known chemotherapeutic agent.

Glycolysis-Related SLC2A1 Is a Potential Pan-Cancer Biomarker for Prognosis and Immunotherapy

SLC2A1 plays a pivotal role in cancer glycometabolism. SLC2A1 has been proposed as a putative driver gene in various cancers. However, a pan-cancer analysis of SLC2A1 has not yet been performed. In this study, we explored the expression and prognosis of SLC2A1 in pan-cancer across multiple databases. We conducted genetic alteration, epigenetic, and functional enrichment analyses of SLC2A. We calculated the correlation between SLC2A1 and tumor microenvironment using the TCGA pan-cancer dataset. We observed high expression levels of SLC2A1 with poor prognosis in most cancers. The overall genetic alteration frequency of SLC2A1 was 1.8% in pan-cancer, and the SLC2A1 promoter was hypomethylation in several cancers. Most m6A-methylation-related genes positively correlated with the expression of SLC2A1 in 33 TCGA cancers. Moreover, SLC2A1 was mainly related to the functions including epithelial-mesenchymal transition, glycolysis, hypoxia, cell-cycle regulation, and DNA repair. Finally, SLC2A1 positively associated with neutrophils and cancer-associated fibroblasts in the tumor microenvironment of most cancers and significantly correlated with TMB and MSI in various cancers. Notably, SLC2A1 was remarkably positively correlated with PD-L1 and CTLA4 in most cancers. SLC2A1 might serve as an attractive pan-cancer biomarker for providing new insights into cancer therapeutics.

Crosstalk between Immune Checkpoint Modulators, Metabolic Reprogramming and Cellular Plasticity in Triple-Negative Breast Cancer

Breast cancer is one of the major causes of mortality in women worldwide. Accounting for 15-20% of all breast cancer diagnoses, the triple-negative breast cancer (TNBC) subtype presents with an aggressive clinical course, heightened metastatic potential and the poorest short-term prognosis. TNBC does not respond to hormonal therapy, only partially responds to radio- and chemotherapy, and has limited targeted therapy options, thus underlining the critical need for better therapeutic treatments. Although immunotherapy based on immune checkpoint inhibition is emerging as a promising treatment option for TNBC patients, activation of cellular plasticity programs such as metabolic reprogramming (MR) and epithelial-to-mesenchymal transition (EMT) causes immunotherapy to fail. In this report, we review the role of MR and EMT in immune checkpoint dysregulation in TNBCs and specifically shed light on development of novel combination treatment modalities for this challenging disease. We highlight the clinical relevance of crosstalk between MR, EMT, and immune checkpoints in TNBCs.

Oligo-Fucoidan supplementation enhances the effect of Olaparib on preventing metastasis and recurrence of triple-negative breast cancer in mice

BACKGROUND

Seaweed polysaccharides have been recommended as anticancer supplements and for boosting human health; however, their benefits in the treatment of triple-negative breast cancers (TNBCs) and improving immune surveillance remain unclear. Olaparib is a first-in-class poly (ADP-ribose) polymerase inhibitor. Oligo-Fucoidan, a low-molecular-weight sulfated polysaccharide purified from brown seaweed (Laminaria japonica), exhibits significant bioactivities that may aid in disease management.

METHODS

Macrophage polarity, clonogenic assays, cancer stemness properties, cancer cell trajectory, glucose metabolism, the TNBC 4T1 cells and a 4T1 syngeneic mouse model were used to inspect the therapeutic effects of olaparib and Oligo-Fucoidan supplementation on TNBC aggressiveness and microenvironment.

RESULTS

Olaparib treatment increased sub-G1 cell death and G2/M arrest in TNBC cells, and these effects were enhanced when Oligo-Fucoidan was added to treat the TNBC cells. The levels of Rad51 and programmed death-ligand 1 (PD-L1) and the activation of epidermal growth factor receptor (EGFR) and adenosine 5'-monophosphate (AMP)-activated protein kinase (AMPK) facilitate drug resistance and TNBC metastasis. However, the combination of olaparib and Oligo-Fucoidan synergistically reduced Rad51 and PD-L1 levels, as well as the activity of EGFR and AMPK; consistently, TNBC cytotoxicity and stemness were inhibited. Oligo-Fucoidan plus olaparib better inhibited the formation of TNBC stem cell mammospheroids with decreased subpopulations of CD44^high/CD24^low and EpCAM^high cells than monotherapy. Importantly, Oligo-Fucoidan plus olaparib repressed the oncogenic interleukin-6 (IL-6)/p-EGFR/PD-L1 pathway, glucose uptake and lactate production. Oligo-Fucoidan induced immunoactive and antitumoral M1 macrophages and attenuated the side effects of olaparib, such as the promotion on immunosuppressive and protumoral M2 macrophages. Furthermore, olaparib plus Oligo-Fucoidan dramatically suppressed M2 macrophage invasiveness and repolarized M2 to the M0-like (F4/80^high) and M1-like (CD80^high and CD86^high) phenotypes. In addition, olaparib- and Oligo-Fucoidan-pretreated TNBC cells resulted in the polarization of M0 macrophages into CD80(+) M1 but not CD163(+) M2 macrophages. Importantly, olaparib supplemented with oral administration of Oligo-Fucoidan in mice inhibited postsurgical TNBC recurrence and metastasis with increased cytotoxic T cells in the lymphatic system and decreased regulatory T cells and M2 macrophages in tumors.

CONCLUSION

Olaparib supplemented with natural compound Oligo-Fucoidan is a novel therapeutic strategy for reprogramming cancer stemness, metabolism and the microenvironment to prevent local postsurgical recurrence and distant metastasis. The combination therapy may advance therapeutic efficacy that prevent metastasis, chemoresistance and mortality in TNBC patients.

FOXD1 facilitates pancreatic cancer cell proliferation, invasion, and metastasis by regulating GLUT1-mediated aerobic glycolysis

Although FOXD1 has been found to be involved in the malignant processes of several types of cancers, its role in pancreatic cancer (PC) is not well understood. This study aimed to investigate the expression and function of FOXD1 in PC. We found that FOXD1 mRNA and protein expression were upregulated in PC tissues compared with non-tumor tissues, and high expression level of FOXD1 was associated with an adverse prognostic index of PC. The results of in vitro and in vivo assays indicate that overexpression of FOXD1 promotes aerobic glycolysis and the capacity of PC cells to proliferate, invade, and metastasize, whereas FOXD1 knockdown inhibits these functions. The results of mechanistic experiments suggest that FOXD1 can not only directly promote SLC2A1 transcription but also inhibit the degradation of SLC2A1 through the RNA-induced silencing complex. As a result, FOXD1 enhances GLUT1 expression and ultimately facilitates PC cell proliferation, invasion, and metastasis by regulating aerobic glycolysis. Taken together, FOXD1 is suggested to be a potential therapeutic target for PC.

Discovery of a Highly Potent and Selective Dual PROTAC Degrader of CDK12 and CDK13

Selective degradation of the cyclin-dependent kinases 12 and 13 (CDK12/13) presents a novel therapeutic opportunity for triple-negative breast cancer (TNBC), but there is still a lack of dual CDK12/13 degraders. Here, we report the discovery of the first series of highly potent and selective dual CDK12/13 degraders by employing the proteolysis-targeting chimera (PROTAC) technology. The optimal compound 7f effectively degraded CDK12 and CDK13 with DC50 values of 2.2 and 2.1 nM, respectively, in MDA-MB-231 breast cancer cells. Global proteomic profiling demonstrated the target selectivity of 7f. In vitro, 7f suppressed expression of core DNA damage response (DDR) genes in a time- and dose-dependent manner. Further, 7f markedly inhibited proliferation of multiple TNBC cell lines including MFM223, with an IC50 value of 47 nM. Importantly, 7f displayed a significantly improved antiproliferative activity compared to the structurally similar inhibitor 4, suggesting the potential advantage of a CDK12/13 degrader for TNBC targeted therapy.

Ubiquitin-Specific Protease 6 n-Terminal-like Protein (USP6NL) and the Epidermal Growth Factor Receptor (EGFR) Signaling Axis Regulates Ubiquitin-Mediated DNA Repair and Temozolomide-Resistance in Glioblastoma

Glioblastoma multiforme (GBM) is the most malignant glioma, with a 30–60% epidermal growth factor receptor (EGFR) mutation. This mutation is associated with unrestricted cell growth and increases the possibility of cancer invasion. Patients with EGFR-mutated GBM often develop resistance to the available treatment modalities and higher recurrence rates. The drug resistance observed is associated with multiple genetic or epigenetic factors. The ubiquitin-specific protease 6 N-terminal-like protein (USP6NL) is a GTPase-activating protein that functions as a deubiquitinating enzyme and regulates endocytosis and signal transduction. It is highly expressed in many cancer types and may promote the growth and proliferation of cancer cells. We hypothesized that USP6NL affects GBM chemoresistance and tumorigenesis, and that its inhibition may be a novel therapeutic strategy for GBM treatment. The USP6NL level, together with EGFR expression in human GBM tissue samples and cell lines associated with therapy resistance, tumor growth, and cancer invasion, were investigated. Its pivotal roles and potential mechanism in modulating tumor growth, and the key mechanism associated with therapy resistance of GBM cells, were studied, both in vitro and in vivo. Herein, we found that deubiquitinase USP6NL and growth factor receptor EGFR were strongly associated with the oncogenicity and resistance of GBM, both in vitro and in vivo, toward temozolomide, as evidenced by enhanced migration, invasion, and acquisition of a highly invasive and drug-resistant phenotype by the GBM cells. Furthermore, abrogation of USP6NL reversed the properties of GBM cells and resensitized them toward temozolomide by enhancing autophagy and reducing the DNA damage repair response. Our results provide novel insights into the probable mechanism through which USP6NL/EGFR signaling might suppress the anticancer therapeutic response, induce cancer invasiveness, and facilitate reduced sensitivity to temozolomide treatment in GBM in an autolysosome-dependent manner. Therefore, controlling the USP6NL may offer an alternative, but efficient, therapeutic strategy for targeting and eradicating otherwise resistant and recurrent phenotypes of aggressive GBM cells.

Complex Feline Disease Mapping Using a Dense Genotyping Array

The current feline genotyping array of 63 k single nucleotide polymorphisms has proven its utility for mapping within breeds, and its use has led to the identification of variants associated with Mendelian traits in purebred cats. However, compared to single gene disorders, association studies of complex diseases, especially with the inclusion of random bred cats with relatively low linkage disequilibrium, require a denser genotyping array and an increased sample size to provide statistically significant associations. Here, we undertook a multi-breed study of 1,122 cats, most of which were admitted and phenotyped for nine common complex feline diseases at the Cornell University Hospital for Animals. Using a proprietary 340 k single nucleotide polymorphism mapping array, we identified significant genome-wide associations with hyperthyroidism, diabetes mellitus, and eosinophilic keratoconjunctivitis. These results provide genomic locations for variant discovery and candidate gene screening for these important complex feline diseases, which are relevant not only to feline health, but also to the development of disease models for comparative studies.

A Review of Metabolic Targets of Anticancer Nutrients and Nutraceuticals in Pre-Clinical Models of Triple-Negative Breast Cancer

Triple-negative breast cancer (TNBC) is a subtype of breast cancer that is notoriously aggressive and has poorer outcomes as compared with other breast cancer subtypes. Due to a lack of targeted therapies, TNBC is often treated with chemotherapeutics as opposed to hormone therapy or other targeted therapies available to individuals with estrogen receptor positive (ER+) breast cancers. Because of the lack of treatment options for TNBC, other therapeutic avenues are being explored. Metabolic reprogramming, a hallmark of cancer, provides potential opportunities to target cancer cells more specifically, increasing efficacy and reducing side effects. Nutrients serve a significant role in metabolic processes involved in DNA transcription, protein folding, and function as co-factors in enzyme activity, and may provide novel strategies to target cancer cell metabolism in TNBC. This article reviews studies that have investigated how nutrients/nutraceuticals target metabolic processes in TNBC cells alone or in combination with existing drugs to exert anticancer effects. These agents have been shown to cause perturbations in many metabolic processes related to glucose metabolism, fatty acid metabolism, as well as autophagy and oxidative stress-related metabolism. With this information, we present the potential of nutrients as metabolism-directed anticancer agents and the potential for using these agents alone or in cocktails as a new direction for TNBC therapy.

SLC2A1 is a Diagnostic Biomarker Involved in Immune Infiltration of Colorectal Cancer and Associated With m6A Modification and ceRNA

Background: Overexpression of solute carrier family 2 member 1 (SLC2A1) promotes glycolysis and proliferation and migration of various tumors. However, there are few comprehensive studies on SLC2A1 in colorectal cancer (CRC).

Methods: Oncomine, The Cancer Genome Atlas (TCGA), and Gene Expression Omnibus (GEO) databases were used to analyze the expression of SLC2A1 in pan-cancer and CRC and analyzed the correlation between SLC2A1 expression and clinical characteristics of TCGA CRC samples. The expression level of SLC2A1 in CRC was certified by cell experiments and immunohistochemical staining analysis. The Genome Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), and Gene Set Enrichment Analysis (GSEA) analyses of SLC2A1 relative genes were completed by bioinformatics analysis. The correlation between SLC2A1 expression level and CRC immune infiltration cell was analyzed by Tumor IMmune Estimation Resource (TIMER), Gene Expression Profiling Interactive Analysis (GEPIA), and TCGA database. The correlation between SLC2A1 expression level and ferroptosis and m6A modification of CRC was analyzed by utilizing TCGA and GEO cohort. Finally, the possible competing endogenous RNA (ceRNA) networks involved in SLC2A1 in CRC are predicted and constructed through various databases.

Results: SLC2A1 is highly expressed not only in CRC but also in many other tumors. ROC curve indicated that SLC2A1 had high predictive accuracy for the outcomes of tumor. The SLC2A1 expression in CRC was closely correlated with tumor stage and progression free interval (PFI). GO, KEGG, and GSEA analysis indicated that SLC2A1 relative genes were involved in multiple biological functions. The analysis of TIMER, GEPIA, and TCGA database indicated that the SLC2A1 mRNA expression was mainly positively associated with neutrophils. By the analysis of the TCGA and GEO cohort, we identified that the expression of SLC2A1 is closely associated to an m6A modification relative gene Insulin Like Growth Factor 2 MRNA Binding Protein 3 (IGF2BP3) and a ferroptosis relative gene Glutathione Peroxidase 4 (GPX4).

Conclusion: SLC2A1 can be used as a biomarker of CRC, which is associated to immune infiltration, m6A modification, ferroptosis, and ceRNA regulatory network of CRC.

The Mechanism of Warburg Effect-Induced Chemoresistance in Cancer

Although chemotherapy can improve the overall survival and prognosis of cancer patients, chemoresistance remains an obstacle due to the diversity, heterogeneity, and adaptability to environmental alters in clinic. To determine more possibilities for cancer therapy, recent studies have begun to explore changes in the metabolism, especially glycolysis. The Warburg effect is a hallmark of cancer that refers to the preference of cancer cells to metabolize glucose anaerobically rather than aerobically, even under normoxia, which contributes to chemoresistance. However, the association between glycolysis and chemoresistance and molecular mechanisms of glycolysis-induced chemoresistance remains unclear. This review describes the mechanism of glycolysis-induced chemoresistance from the aspects of glycolysis process, signaling pathways, tumor microenvironment, and their interactions. The understanding of how glycolysis induces chemoresistance may provide new molecular targets and concepts for cancer therapy.

Glucose Metabolism and Glucose Transporters in Breast Cancer

Breast cancer is the most common malignancy in women worldwide and is associated with high mortality rates despite the continuously advancing treatment strategies. Glucose is essential for cancer cell metabolism owing to the Warburg effect. During the process of glucose metabolism, various glycolytic metabolites, such as serine and glycine metabolites, are produced and other metabolic pathways, such as the pentose phosphate pathway (PPP), are associated with the process. Glucose is transported into the cell by glucose transporters, such as GLUT. Breast cancer shows high expressions of glucose metabolism-related enzymes and GLUT, which are also related to breast cancer prognosis. Triple negative breast cancer (TNBC), which is a high-grade breast cancer, is especially dependent on glucose metabolism. Breast cancer also harbors various stromal cells such as cancer-associated fibroblasts and immune cells as tumor microenvironment, and there exists a metabolic interaction between these stromal cells and breast cancer cells as explained by the reverse Warburg effect. Breast cancer is heterogeneous, and, consequently, its metabolic status is also diverse, which is especially affected by the molecular subtype, progression stage, and metastatic site. In this review, we will focus on glucose metabolism and glucose transporters in breast cancer, and we will additionally discuss their potential applications as cancer imaging tracers and treatment targets.

TNBC: Potential Targeting of Multiple Receptors for a Therapeutic Breakthrough, Nanomedicine, and Immunotherapy

Triple-negative breast cancer (TNBC) is a heterogeneous, recurring cancer associated with a high rate of metastasis, poor prognosis, and lack of therapeutic targets. Although target-based therapeutic options are approved for other cancers, only limited therapeutic options are available for TNBC. Cell signaling and receptor-specific targets are reportedly effective in patients with TNBC under specific clinical conditions. However, most of these cancers are unresponsive, and there is a requirement for more effective treatment modalities. Further, there is a lack of effective biomarkers that can distinguish TNBC from other BC subtypes. ER, PR, and HER2 help identify TNBC and are widely used to identify patients who are most likely to respond to diverse therapeutic strategies. In this review, we discuss the possible treatment options for TNBC based on its inherent subtype receptors and pathways, such as p53 signaling, AKT signaling, cell cycle regulation, DNA damage, and programmed cell death, which play essential roles at multiple stages of TNBC development. We focus on poly-ADP ribose polymerase 1, androgen receptor, vascular endothelial growth factor receptor, and epidermal growth factor receptor as well as the application of nanomedicine and immunotherapy in TNBC and discuss their potential applications in drug development for TNBC.

Comprehensive Analysis of GLUT1 Immune Infiltrates and ceRNA Network in Human Esophageal Carcinoma

Background

Glucose transporter 1 (GLUT1) is encoded by the solute carrier family 2A1 (SLC2A1) gene and is one of the glucose transporters with the greatest affinity for glucose. Abnormal expression of GLUT1 is associated with a variety of cancers. However, the biological role of GLUT1 in esophageal carcinoma (ESCA) remains to be determined.

Methods

We analyzed the expression of GLUT1 in pan-cancer and ESCA as well as clinicopathological analysis through multiple databases. Use R and STRING to perform GO/KEGG function enrichment and PPI analysis for GLUT1 co-expression. TIMER and CIBERSORT were used to analyze the relationship between GLUT1 expression and immune infiltration in ESCA. The TCGA ESCA cohort was used to analyze the relationship between GLUT1 expression and m6A modification in ESCA, and to construct a regulatory network in line with the ceRNA hypothesis.

Results

GLUT1 is highly expressed in a variety of tumors including ESCA, and is closely related to histological types and histological grade. GO/KEGG functional enrichment analysis revealed that GLUT1 is closely related to structural constituent of cytoskeleton, intermediate filament binding, cell-cell adheres junction, epidermis development, and P53 signaling pathway. PPI shows that GLUT1 is closely related to TP53, GIPC1 and INS, and these three proteins all play an important role in tumor proliferation. CIBERSORT analysis showed that GLUT1 expression is related to the infiltration of multiple immune cells. When GLUT1 is highly expressed, the number of memory B cells decreases. ESCA cohort analysis found that GLUT1 expression was related to 7 m6A modifier genes. Six possible crRNA networks in ESCA were constructed by correlation analysis, and all these ceRNA networks contained GLUT1.

Conclusion

GLUT1 can be used as a biomarker for the diagnosis and treatment of ESCA, and is related to tumor immune infiltration, m6A modification and ceRNA network.

Oxidative Stress-Induced Unscheduled CDK1-Cyclin B1 Activity Impairs ER-Mitochondria-Mediated Bioenergetic Metabolism

Targeting the activities of endoplasmic reticulum (ER)-mitochondrial-dependent metabolic reprogramming is considered one of the most promising strategies for cancer treatment. Here, we present biochemical subcellular fractionation, coimmunoprecipitation, gene manipulation, and pharmacologic evidence that induction of mitochondria-localized phospho (p)-cyclin dependent kinase 1 (CDK1) (Thr 161)-cyclin B1 complexes by apigenin in nasopharyngeal carcinoma (NPC) cells impairs the ER-mitochondrial bioenergetics and redox regulation of calcium (Ca⁺⁺) homeostasis through suppressing the B cell lymphoma 2 (BCL-2)/BCL-2/B-cell lymphoma-extra large (BCL-x_L)-modulated anti-apoptotic and metabolic functions. Using a specific inducer, inhibitor, or short hairpin RNA for acid sphingomyelinase (ASM) demonstrated that enhanced lipid raft-associated ASM activity confers alteration of the lipid composition of lipid raft membranes, which leads to perturbation of protein trafficking, and induces formation of p110α free p85α-unphosphorylated phosphatase and tensin homolog deleted from chromosome 10 complexes in the lipid raft membranes, causing disruption of phosphatidylinositol 3-kinase (PI3K)-protein kinase B (Akt)-GTP-ras-related C3 botulinum toxin substrate 1 (Rac1)-mediated signaling, thus triggering the p-CDK1 (Thr 161))-cyclin B1-mediated BCL-2 (Thr 69/Ser 87)/BCL-x_L (Ser 62) phosphorylation and accompanying impairment of ER-mitochondria-regulated bioenergetic, redox, and Ca⁺⁺ homeostasis. Inhibition of apigenin-induced reactive oxygen species (ROS) generation by a ROS scavenger N-acetyl-L-cysteine blocked the lipid raft membrane localization and activation of ASM and formation of ceramide-enriched lipid raft membranes, returned PI3K-Akt-GTP-Rac1-modulated CDK1-cyclin B1 activity, and subsequently restored the BCL-2/BCL-x_L-regulated ER-mitochondrial bioenergetic activity. Thus, this study reveals a novel molecular mechanism of the pro-apoptotic activity of ASM controlled by oxidative stress to modulate the ER-mitochondrial bioenergetic metabolism, as well as suggests the disruption of CDK1-cyclin B1-mediated BCL-2/BCL-x_L oncogenic activity by triggering oxidative stress-ASM-induced PI3K-Akt-GTP-Rac1 inactivation as a therapeutic approach for NPC.

Hyperglycemia and Chemoresistance in Breast Cancer: From Cellular Mechanisms to Treatment Response

Female breast cancer is a complex, multifactorial disease. Studies have shown that hyperglycemia is one of the most important contributing factors to increasing the risk of breast cancer that also has a major impact on the efficacy of chemotherapy. At the cellular level, hyperglycemia can promote the proliferation, invasion, and migration of breast cancer cells and can also induce anti-apoptotic responses to enhance the chemoresistance of tumors via abnormal glucose metabolism. In this article, we focus on the latest progress in defining the mechanisms of chemotherapy resistance in hyperglycemic patients including the abnormal behaviors of cancer cells in the hyperglycemic microenvironment and the impact of abnormal glucose metabolism on key signaling pathways. To better understand the advantages and challenges of breast cancer treatments, we explore the causes of drug resistance in hyperglycemic patients that may help to better inform the development of effective treatments.

Akt regulates RSK2 to alter phosphorylation level of H2A.X in breast cancer

Histone H2AX (H2A.X) is a variant of the histone H2A family. Phosphorylation of H2A.X is a marker of DNA strand breaks and the presence or absence of H2A.X is closely related to tumor susceptibility and drug resistance. The present study found that the activity of the serine/threonine kinase Akt was negatively associated with H2A.X phosphorylated at the Ser16 site (H2A.X S16ph), but the mechanism of the inverse relationship remains elusive. The aim of the present study was to elucidate the mechanism of action between Akt and H2A.X S16ph and the exact role of this mechanism. Western blot analysis was performed to detect the regulatory association between p-Akt and H2A.X S16ph/p-RSK2, and immunoprecipitation and chromatin immunoprecipitation were performed to prove that Akt, RSK2 and H2A.X combine and interact in human breast cancer cells. The changes of cellular proliferation and migration induced by the interaction of Akt, RSK2 and H2A.X was determined by MTT, soft agar colony formation and cell migration experiments. The effect of interaction of Akt, RSK2 and H2A.X on cancer-promoting genes, such as PSAT-1 was determined via reverse transcription-quantitative PCR analysis. The current study indicated that the serine/threonine kinase ribosomal S6 kinase 2 (RSK2) as a kinase of H2A.X could be phosphorylated by Akt at Ser19 site. Moreover, Akt positively regulated the phosphorylation of RSK2 to inhibit phosphorylation of H2A.X, thereby affecting the affinity between RSK2 and substrate histone, promoting the survival and migration of breast cancer cells. In conclusion, Akt-mediated phosphorylation of RSK2 regulated the phosphorylation of H2A.X, thereby promoting oncogenic activity. This finding provides new insights to understand the pathogenesis and treatment mechanisms of breast cancer.

Lactate Metabolism and Immune Modulation in Breast Cancer: A Focused Review on Triple Negative Breast Tumors

Triple negative breast cancer (TNBC) is an aggressive subtype of breast cancer associated with poor prognosis, early recurrence, and the lack of durable chemotherapy responses and specific targeted treatments. The recent FDA approval for immune checkpoint inhibition in combination with nab-paclitaxel for the treatment of metastatic TNBC created opportunity to advocate for immunotherapy in TNBC patients. However, improving the current low response rates is vital. Most cancers, including TNBC tumors, display metabolic plasticity and undergo reprogramming into highly glycolytic tumors through the Warburg effect. Consequently, accumulation of the metabolic byproduct lactate and extracellular acidification is often observed in several solid tumors, thereby exacerbating tumor cell proliferation, metastasis, and angiogenesis. In this review, we focus on the role of lactate acidosis in the microenvironment of glycolytic breast tumors as a major driver for immune evasion with a special emphasis on TNBCs. In particular, we will discuss the role of lactate regulators such as glucose transporters, lactate dehydrogenases, and lactate transporters in modulating immune functionality and checkpoint expression in numerous immune cell types. This review aims to spark discussion on interventions targeting lactate acidosis in combination with immunotherapy to provide an effective means of improving response to immune checkpoint inhibitors in TNBC, in addition to highlighting challenges that may arise from TNBC tumor heterogeneity.

Current Progresses and Challenges of Immunotherapy in Triple-Negative Breast Cancer

With improved understanding of the immunogenicity of triple-negative breast cancer (TNBC), immunotherapy has emerged as a promising candidate to treat this lethal disease owing to the lack of specific targets and effective treatments. While immune checkpoint inhibition (ICI) has been effectively used in immunotherapy for several types of solid tumor, monotherapies targeting programmed death 1 (PD-1), its ligand PD-L1, or cytotoxic T lymphocyte-associated protein 4 (CTLA-4) have shown little efficacy for TNBC patients. Over the past few years, various therapeutic candidates have been reviewed, attempting to improve ICI efficacy on TNBC through combinatorial treatment. In this review, we describe the clinical limitations of ICI and illustrate candidates from an immunological, pharmacological, and metabolic perspective that may potentiate therapy to improve the outcomes of TNBC patients.

Liver Expression of IGF2 and Related Proteins in ZBED6 Gene-Edited Pig by RNA-Seq

Simple Summary

Zinc finger BED-type containing 6 (ZBED6), as a regulatory factor, has different regulatory mechanisms in animal development. The intron of insulin-like growth factor 2 (IGF2) regulates the development of animal muscle and adipose by combining with the binding site of ZBED6. As a member of the insulin-like growth factor family, IGF2 plays an important role in embryonic growth and development, cell proliferation, muscle growth and genome imprinting. In order to further study the regulatory mechanism of ZBED6 on IGF2, we detected the expression of IGF2 and related genes in ZBED6 single allele knockout (ZBED6-SKO) pig tissues and analyzed differently expressed genes of the transcriptome of ZBED6-SKO pig liver. The results showed that the partial knockout of ZBED6 could affect the secretion of IGF2 in pig liver but had no significant difference at the protein level. This research provides a new idea for the interaction between IGF2 and ZBED6.

Abstract

Zinc finger BED-type containing 6 (ZBED6), a highly conservative transcription factor of placental mammals, has conservative interaction of insulin-like growth factor 2 (IGF2) based on the 16 bp binding sites of ZBED6 on the IGF2 sequence. IGF2 is related to embryo growth and cell proliferation. At the same time, its functions in muscle and adipose in mammals have been widely mentioned in recent studies. To further investigate the mechanism of ZBED6 on IGF2, we detected the expression of IGF2 and related genes in ZBED6 single allele knockout (ZBED6-SKO) pig tissues and analyzed the transcriptome of ZBED6-SKO pig liver. Through RNA-seq, we captured nine up-regulated genes and eight down-regulated genes which related to lipid metabolism. The results showed that the mRNA of IGF2 had an upward trend after the partial knockout of ZBED6 in liver and had no significant difference in protein expression of IGF2. In summary, ZBED6-SKO could affect the secretion of IGF2 in pig liver and its own lipid metabolism. Our research has provided basic information for revealing the regulatory mechanism of the interaction between ZBED6 and IGF2 in mammals.

USP6NL mediated by LINC00689/miR-142-3p promotes the development of triple-negative breast cancer

Background

Triple-negative breast cancer (TNBC), in part because of the high metastasis rate, is one of the most prevalent causes of malignancy-related mortality globally. Ubiquitin specific peptidase 6 N-terminal like (USP6NL) has been unmasked to be implicated in some human cancers. However, the precise biological function of USP6NL in TNBC has not been defined.

Methods

RNA expression was examined by real-time quantitative PCR (RT-qPCR), while USP6NL protein level was tested through western blot. Besides, cell proliferation was assessed by using colony formation assay, whereas cell apoptosis estimated by flow cytometry analysis, JC-1 assay and TUNEL assay. Transwell assays were adopted to detect the migration and invasion of indicated TNBC cells. Immunofluorescence (IF) assay evaluated epithelial-mesenchymal transitions (EMT) progress in TNBC. Further, RNA immunoprecipitation (RIP), RNA pull down and luciferase reporter assays were implemented for measuring the mutual interplay among USP6NL, miR-142-3p and long intergenic non-protein coding RNA 689 (LINC00689).

Results

Elevated USP6NL level was uncovered in TNBC cells. RNA interference-mediated knockdown of USP6NL inhibited TNBC cell growth, motility and EMT. Further, USP6NL was proved as the target of a tumor-inhibitor miR-142-3p, and LINC00689 augmented USP6NL expression by absorbing miR-142-3p. Importantly, miR-142-3p deficiency or USP6NL overexpression fully abolished the inhibitory effect of LINC00689 silence on TNBC cellular behaviors.

Conclusion

All data revealed the important role of USP6NL/LINC00689/miR-142-3p signaling in TNBC. The findings might provide a new and promising therapeutic biomarker for treating patients with TNBC.

Flavonoids against the Warburg phenotype-concepts of predictive, preventive and personalised medicine to cut the Gordian knot of cancer cell metabolism

The Warburg effect is characterised by increased glucose uptake and lactate secretion in cancer cells resulting from metabolic transformation in tumour tissue. The corresponding molecular pathways switch from oxidative phosphorylation to aerobic glycolysis, due to changes in glucose degradation mechanisms known as the 'Warburg reprogramming' of cancer cells. Key glycolytic enzymes, glucose transporters and transcription factors involved in the Warburg transformation are frequently dysregulated during carcinogenesis considered as promising diagnostic and prognostic markers as well as treatment targets. Flavonoids are molecules with pleiotropic activities. The metabolism-regulating anticancer effects of flavonoids are broadly demonstrated in preclinical studies. Flavonoids modulate key pathways involved in the Warburg phenotype including but not limited to PKM2, HK2, GLUT1 and HIF-1. The corresponding molecular mechanisms and clinical relevance of 'anti-Warburg' effects of flavonoids are discussed in this review article. The most prominent examples are provided for the potential application of targeted 'anti-Warburg' measures in cancer management. Individualised profiling and patient stratification are presented as powerful tools for implementing targeted 'anti-Warburg' measures in the context of predictive, preventive and personalised medicine.

Enforced C-Src Activation Causes Compartmental Dysregulation of PI3K and PTEN Molecules in Lipid Rafts of Tongue Squamous Carcinoma Cells by Attenuating Rac1-Akt-GLUT-1-Mediated Sphingolipid Synthesis

Pharmacologic intervention to affect the membrane lipid homeostasis of lipid rafts is a potent therapeutic strategy for cancer. Here we showed that gallic acid (GA) caused the complex formation of inactive Ras-related C3 botulinum toxin substrate 1 (Rac1)-phospho (p)-casein kinase 2 α (CK2α) (Tyr 255) in human tongue squamous carcinoma (TSC) cells, which disturbed the lipid raft membrane-targeting of phosphatidylinositol 3-kinase (PI3K)-Rac1-protein kinase B (Akt) signal molecules by inducing the association of p110α-free p85α with unphosphorylated phosphatase tensin homolog deleted on chromosome 10 (PTEN) in lipid rafts. The effects on induction of inactive Rac1-p-CK2α (Tyr 255) complex formation and attenuation of p-Akt (Ser 473), GTP-Rac1, glucose transporter-1 (GLUT-1) lipid raft membrane-targeting, and cell invasive activity by GA were counteracted either by CK2α short hairpin RNA or cellular-Src (c-Src) inhibitor PP1. PP1 treatment, GLUT-1 or constitutively active Rac1 ectopic-expression blocked GA-induced decreases in cellular glucose, sphingolipid and cholesterol of lipid raft membranes, p85α-p110α-GTP-Rac1 complexes, glucosylceramide synthase activity and increase in ceramide and p110α-free p85α-PTEN complex levels of lipid raft membranes, which reversed the inhibition on matrix metalloproteinase (MMP)-2/-9-mediated cell invasion induced by GA. Using transient ectopic expression of nuclear factor-kappa B (NF-κB) p65, MMP-2/-9 promoter-driven luciferase, and NF-κB-dependent luciferase reporter genes and NF-κB specific inhibitors or Rac1 specific inhibitor NSC23766, we confirmed that an attenuation of Rac1 activity by GA confers inhibition of NF-κB-mediated MMP-2/-9 expression and cell invasion. In conclusion, GA-induced c-Src activation is a key inductive event for the formation of inactive Rac1-p-CK2α (Tyr 255) complexes, which disturbed lipid raft compartment of PI3K and PTEN molecules by impairing Akt-regulated GLUT-1-mediated sphingolipid synthesis, and finally resulting in inhibition of TSC cell invasion.

Long noncoding RNA KCNQ1OT1 promotes colorectal carcinogenesis by enhancing aerobic glycolysis via hexokinase-2

In this study, we investigated the mechanistic role and prognostic significance of the long coding RNA (lncRNA) KCNQ1OT1 in colorectal cancer (CRC). KCNQ1OT1 levels were significantly higher in CRC tissues than adjacent normal colorectal tissues (n=79). High KCNQ1OT1 expression correlated with poorer prognosis in CRC patients. KCNQ1OT1-silenced CRC cells showed reduced proliferation, colony formation, extracellular acidification, and lactate and glucose secretion. This suggests KCNQ1OT1 promotes CRC cell proliferation by increasing aerobic glycolysis. RNA pull-down assays with biotinylated KCNQ1OT1 followed by mass spectrometry analysis showed that KCNQ1OT1 directly binds to hexokinase 2 (HK2). This was confirmed by RNA immunoprecipitation assays using anti-hexokinase 2 antibody. HK2 protein levels were reduced in KCNQ1OT1 knockdown CRC cells, but were restored by treatment with the proteasomal inhibitor MG132. KCNQ1OT1 knockdown CRC cells also showed higher ubiquitinated-HK2 levels, suggesting KCNQ1OT1 enhances aerobic glycolysis by stabilizing HK2. HK2 overexpression in KCNQ1OT1 knockdown CRC cells restored proliferation and aerobic glycolysis. KCNQ1OT1 levels correlated positively with HK2 expression and prognosis in CRC patients. These findings show that KCNQ1OT1 promotes colorectal carcinogenesis by increasing aerobic glycolysis through HK2.

Metabolic reprogramming in triple-negative breast cancer

Since triple-negative breast cancer (TNBC) was first defined over a decade ago, increasing studies have focused on its genetic and molecular characteristics. Patients diagnosed with TNBC, compared to those diagnosed with other breast cancer subtypes, have relatively poor outcomes due to high tumor aggressiveness and lack of targeted treatment. Metabolic reprogramming, an emerging hallmark of cancer, is hijacked by TNBC to fulfill bioenergetic and biosynthetic demands; maintain the redox balance; and further promote oncogenic signaling, cell proliferation, and metastasis. Understanding the mechanisms of metabolic remodeling may guide the design of metabolic strategies for the effective intervention of TNBC. Here, we review the metabolic reprogramming of glycolysis, oxidative phosphorylation, amino acid metabolism, lipid metabolism, and other branched pathways in TNBC and explore opportunities for new biomarkers, imaging modalities, and metabolically targeted therapies.

The role of deubiquitinating enzymes in gastric cancer

The epigenetic regulation of gene expression (via DNA methylation, histone modification and microRNA interference) contributes to a variety of diseases, particularly cancer. Protein deubiquitination serves a key role in the mechanism underlying histone modification, and consequently influences tumor development and progression. Improved characterization of the role of ubiquitinating enzymes has led to the identification of numerous deubiquitinating enzymes (DUBs) with various functions. Gastric cancer (GC) is a highly prevalent cancer type that exhibits a high mortality rate. Latest analysis about cancer patient revealed that GC is sixth deadliest cancer type, which frequently occur in male (7.2%) than female (4.1%). Complex associations between DUBs and GC progression have been revealed in multiple studies; however, the molecular mechanism underpinning the metastasis and recurrence of GC is yet to be elucidated. Generally, DUBs were upregulated in gastric cancer. The relation of DUBs and tumor size, classification and staging was observed in GC. Besides, 5-yar survival rate of patients with GC is effeccted by expression level of DUBs. Among the highly expressed DUBs, specifically six DUBs namely UCHs, USPs, OTUs, MJDs, JAMMs and MCPIPs effect on this survival rate. Consequently, the association between GC and DUBs has received increasing attention in recent years. Therefore, in the present review, literature investigating the association between DUBs and GC pathophysiology was analyzed and critically appraised.

Second Generation mTOR Inhibitors as a Double-Edged Sword in Malignant Glioma Treatment

Glioblastomas (GBs) frequently display activation of the epidermal growth factor receptor (EGFR) and mammalian target of rapamycin (mTOR). mTOR exists as part of two multiprotein complexes, mTOR complex 1 (mTORC1) and 2 (mTORC2). In GBs, mTORC1 inhibitors such as rapamycin have performed poorly in clinical trials, and in vitro protect GB cells from nutrient and oxygen deprivation. Next generation ATP-competitive mTOR inhibitors with affinity for both mTOR complexes have been developed, but data exploring their effects on GB metabolism are scarce. In this study, we compared the ATP-competitive mTORC1/2 inhibitors torin2, INK-128 and NVP-Bez235 to the allosteric mTORC1 inhibitor rapamycin under conditions that mimic the glioma microenvironment. In addition to inhibiting mTORC2 signaling, INK-128 and NVP-Bez235 more effectively blocked mTORC1 signaling and prompted a stronger cell growth inhibition, partly by inducing cell cycle arrest. However, under hypoxic and nutrient-poor conditions mTORC1/2 inhibitors displayed even stronger cytoprotective effects than rapamycin by reducing oxygen and glucose consumption. Thus, therapies that arrest proliferation and inhibit anabolic metabolism must be expected to improve energy homeostasis of tumor cells. These results mandate caution when treating physiologically or therapeutically induced hypoxic GBs with mTOR inhibitors.

Clinicopathological Features of Triple-Negative Breast Cancer Epigenetic Subtypes

BACKGROUND/OBJECTIVE

Triple-negative breast cancer (TNBC) is a heterogeneous collection of breast tumors with numerous differences including morphological characteristics, genetic makeup, immune-cell infiltration, and response to systemic therapy. DNA methylation profiling is a robust tool to accurately identify disease-specific subtypes. We aimed to generate an epigenetic subclassification of TNBC tumors (epitypes) with utility for clinical decision-making.

METHODS

Genome-wide DNA methylation profiles from TNBC patients generated in the Cancer Genome Atlas project were used to build machine learning-based epigenetic classifiers. Clinical and demographic variables, as well as gene expression and gene mutation data from the same cohort, were integrated to further refine the TNBC epitypes.

RESULTS

This analysis indicated the existence of four TNBC epitypes, named as Epi-CL-A, Epi-CL-B, Epi-CL-C, and Epi-CL-D. Patients with Epi-CL-B tumors showed significantly shorter disease-free survival and overall survival [log rank; P = 0.01; hazard ratio (HR) 3.89, 95% confidence interval (CI) 1.3-11.63 and P = 0.003; HR 5.29, 95% CI 1.55-18.18, respectively]. Significant gene expression and mutation differences among the TNBC epitypes suggested alternative pathway activation that could be used as ancillary therapeutic targets. These epigenetic subtypes showed complementarity with the recently described TNBC transcriptomic subtypes.

CONCLUSIONS

TNBC epigenetic subtypes exhibit significant clinical and molecular differences. The links between genetic make-up, gene expression programs, and epigenetic subtypes open new avenues in the development of laboratory tests to more efficiently stratify TNBC patients, helping optimize tailored treatment approaches.

Insulin-like growth factor 2 mRNA binding protein 2 promotes aerobic glycolysis and cell proliferation in pancreatic ductal adenocarcinoma via stabilizing GLUT1 mRNA

Insulin-like growth factor 2 mRNA binding protein 2 (IGF2BP2) is a member of the IGF2BP protein family consisting of IGF2BP1~3 with the capacity of binding to many transcripts and regulating RNA stability, localization, and translation. In this study, we discovered that expression of IGF2BP2 was upregulated and led to a poor prognosis in pancreatic ductal adenocarcinoma (PDAC). IGF2BP2 protein was gradually elevated from normal pancreas, pancreatic intraepithelial neoplasia to PDAC in an LSL-KrasG12D/+;LSL-Trp53R172H/+;Pdx1-Cre mouse model. Furthermore, we demonstrated that IGF2BP2 promoted aerobic glycolysis and PDAC cell proliferation through directly binding to and stabilizing GLUT1 mRNA. In summary, our study unveiled an important role of IGF2BP2 in PDAC development by modulating aerobic glycolysis and as a potential therapeutic target for PDAC treatment.

Tre2 (USP6NL) promotes colorectal cancer cell proliferation via Wnt/β-catenin pathway

Background

Most colorectal cancer (CRC) patients are diagnosed at an advanced or metastatic stage with poor prognosis. Ubiquitin-specific protease 6 N-terminal-like protein (USP6NL) with high expression in CRC tissues regulates CRC cell proliferation via Wnt/β-catenin pathway. We hypothesized that USP6NL impacts CRC growth and inhibition of USP6NL may be a novel treatment strategy to improve CRC therapy.

Methods

USP6NL level in human CRC tissues and its association with tumor growth and metastasis were examined. Its roles and potential mechanisms in regulating tumor growth were studied by genetic and pharmacological manipulation of CRC cells in vitro and in vivo.

Results

Herein, we found that USP6NL was up-regulated in tumorous tissues of CRC patients. Our data suggested that knockdown of USP6NL in human CRC cell lines (HCT116 and LOVO cells) inhibited cell proliferation, induced G0/G1 cell cycle arrest, and prevented the tumorigenicity of HCT116 cells in nude mice, and which was associated with the prevention of Wnt/β-catenin pathway. On the contrary, USP6NL overexpression in human CRC cells (SW480) showed the opposite result. Our data suggested that the promoted cell proliferation, G1/S cell cycle progression, and the enhanced expression of β-catenin Cyclin D1 and C-myc while reduced P27 induced by the overexpression of USP6NL were significantly reversed by additional treatment of XAV939, indicating that activating Wnt/β-catenin pathway was the mechanism, by which USP6NL exerted carcinogenesis in CRC in vitro. Besides, our data suggested that knockdown of USP6NL increased the ubiquitination of β-catenin, indicating that USP6NL may serve as a deubiquitinase that regulated β-catenin accumulation in this process. Furthermore, 10058-F4 down-regulated USP6NL, inhibited CRC cell proliferation and induced cell cycle arrest. The result demonstrated a possible feedback loop between USP6NL, β-catenin and C-myc in regulating CRC cell growth.

Conclusion

USP6NL was an oncogene in CRC, and it may be a potential target for the treatment of CRC.

Inhibition of EGFR signaling with Spautin-1 represents a novel therapeutics for prostate cancer

Background

Prostate cancer (PCa) remains a challenge worldwide. Due to the development of castration-resistance, traditional first-line androgen deprivation therapy (ADT) became powerlessness. Epidermal growth factor receptor (EGFR) is a well characterized therapeutic target to treat colorectal carcinoma and non-small cell lung cancer. Increasing studies have unraveled the significance of EGFR and its downstream signaling in the progression of castration-resistant PCa.

Method

MTS, colony formation and Edu staining assays were used to analyze the cell proliferation of PCa cells. Flow cytometry was used to analyze PCa cell cycle distribution and cell apoptosis. Western blot was used to measure the expression of key proteins associated with cell cycle progression, apoptosis and EGFR signaling pathways. Transfection of exogenous small interfering RNA (siRNA) or plasmid was used to intervene specific gene expression. Nude mouse model was employed to test the in vivo effect of Spautin-1.

Results

The current study reveals that Spautin-1, a known inhibitor of ubiquitin-specific peptidase 10 (USP10) and USP13, inhibits EGFR phosphorylation and the activation of its downstream signaling. Inhibition of EGFR signaling induced by Spautin-1 leads to cell cycle arrest and apoptosis of PCa in a USP10/USP13 independent manner. The application of Spautin-1 reduces the expression of glucose transporter 1 (Glut1) and dramatically induces cell death under glucose deprivation condition. In vivo experiments show a potent anti-tumor effect of Spautin-1 alone and in combination with Enzalutamide.

Conclusion

This study demonstrates the therapeutic potential of EGFR signaling inhibition by the use of Spautin-1 for PCa treatment.

Electronic supplementary material

The online version of this article (10.1186/s13046-019-1165-4) contains supplementary material, which is available to authorized users.

Targeting cancer metabolism through synthetic lethality-based combinatorial treatment strategies

PURPOSE OF REVIEW

Targeting cancer metabolism for therapy has received much attention over the last decade with various small molecule inhibitors entering clinical trials. The present review highlights the latest strategies to target glucose and glutamine metabolism for cancer therapy with a particular emphasis on novel combinatorial treatment approaches.

RECENT FINDINGS

Inhibitors of glucose, lactate, and glutamine transport and the ensuing metabolism are in preclinical to clinical trial stages of investigation. Recent advances in our understanding of cell-intrinsic and cell-extrinsic factors that dictate dependence on these targets have informed the development of rational, synthetic lethality-based strategies to exploit these metabolic vulnerabilities.

SUMMARY

Cancer cells exhibit a number of metabolic alterations with functional consequences beyond that of sustaining cellular energetics and biosynthesis. Elucidating context-specific metabolic dependencies and their connections to oncogenic signaling and epigenetic programs in tumor cells represents a promising approach to identify new metabolic drug targets for cancer therapy.

Isoforms S and L of MRPL33 from alternative splicing have isoform‑specific roles in the chemoresponse to epirubicin in gastric cancer cells via the PI3K/AKT signaling pathway

Drug resistance is a major cause of cancer-associated mortality. Epirubicin-based chemotherapy initially benefits patients with metastatic or advanced gastric cancer; however, tumor recurrence can occur following several courses of treatment. Mitochondrial ribosomal protein L33 (MRPL33)-long (L) and MRPL33-short (S), isoforms of MRPL33 that arise from AS, have been reported to regulate cell growth and apoptosis in cancer; however, few studies have evaluated the roles of MRPL33-L and MRPL33-S in gastric cancer. In the present study, MRPL33-L was demonstrated to be significantly more abundant in gastric tumor tissues than the MRPL33-S isoform. MRPL33-S promoted chemosensitivity to epirubicin in gastric cancer as demonstrated by a chemoresponse assay; chemosensitivity was suppressed in response to MRPL33-L. Gene microarray analysis was performed to investigate the underlying mechanisms. Bioinformatic analysis revealed that overexpression of MRPL33-L and MRPL33-S served critical roles in transcription, signal transduction and apoptosis. In particular, the phosphoinositide 3-kinase (PI3K)/AKT serine/threonine kinase (AKT) signaling pathway was markedly regulated. A total of 36 target genes, including PIK3 regulatory subunit α, AKT2, cAMP response element-binding protein (CREB) 1, forkhead box 3, glycogen synthase kinase 3β and mammalian target of rapamycin, which are involved in the PI3K/AKT signaling pathway, were selected for further investigation via protein-protein interaction network and Kyoto Encyclopedia of Genes and Genomes pathway analyses. Furthermore, western blot analysis indicated that MRPL33-S promoted the chemoresponse to epirubicin by deactivating PI3K/AKT/CREB signaling and inducing apoptosis, while MRPL33-L had the opposite effects. In conclusion, the results of the present study revealed that isoforms S and L of MRPL33, which arise from alternative splicing, exhibited opposing roles in the chemoresponse to epirubicin in gastric cancer via the PI3K/AKT signaling pathway. These findings may contribute to the development of potential therapeutic strategies for the resensitization of patients with gastric cancer to epirubicin treatment.

Ovarian Cancer Relies on Glucose Transporter 1 to Fuel Glycolysis and Growth: Anti-Tumor Activity of BAY-876

The recent progresses in understanding of cancer glycolytic phenotype have offered new strategies to manage ovarian cancer and other malignancies. However, therapeutic targeting of glycolysis to treat cancer remains unsuccessful due to complex mechanisms of tumor glycolysis and the lack of selective, potent and safe glycolytic inhibitors. Recently, BAY-876 was identified as a new-generation inhibitor of glucose transporter 1 (GLUT1), a GLUT isoform commonly overexpressed but functionally poorly defined in ovarian cancer. Notably, BAY-876 has not been evaluated in any cell or preclinical animal models since its discovery. We herein took advantage of BAY-876 and molecular approaches to study GLUT1 regulation, targetability, and functional relevance to cancer glycolysis. The anti-tumor activity of BAY-876 was evaluated with ovarian cancer cell line- and patient-derived xenograft (PDX) models. Our results show that inhibition of GLUT1 is sufficient to block basal and stress-regulated glycolysis, and anchorage-dependent and independent growth of ovarian cancer cells. BAY-876 dramatically inhibits tumorigenicity of both cell line-derived xenografts and PDXs. These studies provide direct evidence that GLUT1 is causally linked to the glycolytic phenotype in ovarian cancer. BAY-876 is a potent blocker of GLUT1 activity, glycolytic metabolism and ovarian cancer growth, holding promise as a novel glycolysis-targeted anti-cancer agent.

Knockdown of PKM2 suppresses tumor progression in human cervical cancer by modulating epithelial-mesenchymal transition via Wnt/β-catenin signaling

Background

Pyruvate kinase isozyme type M2 (PKM2) is a key glycolytic enzyme and is upregulated in multiple human malignancies. However, the role of PKM2 in human cervical cancer (CC) remains elusive. Thus, this study explored the role of PKM2 in CC by detecting its expression patterns in human CC tissues and cell lines and investigated its effects on cell proliferation and invasion.

Materials and methods

Quantitative reverse transcription polymerase chain reaction (qRT-PCR), immunohistochemistry and western blotting assays were used to detect the expression of PKM2 in CC tissues and CC cells. In vitro, we overexpressed and knocked down PKM2 expression in CC cell lines and investigated the biological function and underlying mechanism of PKM2 in cervical carcinogenesis.

Results

The results showed that PKM2 mRNA and protein were highly expressed in CC tissues and cell lines. Furthermore, increasing PKM2 expression was closely correlated with the clinical stage (P=0.001) and lymph node metastasis (P=0.023). The functional roles of PKM2 were determined using Cell Counting Kit-8, colony formation, and transwell assays. The results showed that PKM2 knockdown inhibited cell proliferation and the migratory and invasive capacities of CC cells, suppressed epithelial–mesenchymal transition (EMT), and inhibited Wnt/β-catenin signaling in vitro. However, overexpression of PKM2 led to increased proliferation and invasion activity as well as the EMT in CC cells.

Conclusion

Taken together, our study results revealed that PKM2 may act as a molecular target for CC treatment.

Birth order and multiple sclerosis

Metabolic reprogramming is an emerging hallmark of cancer cells, in which cancer cells exhibit distinct metabolic phenotypes to fuel their proliferation and progression. The significant advancements made in the area of metabolic reprogramming make possible new strategies for overcoming malignant cancer, including triple-negative breast cancer. Triple-negative breast cancer (TNBC) is associated with high histologic grade, aggressive phenotype, and poor prognosis. Even though triple-negative breast cancer patients benefit from standard chemotherapy, they still face high recurrence rates and are more likely to develop resistance to chemotherapeutic drugs. Therefore, there is an urgent need to explore vulnerabilities of triple-negative breast cancer and develop novel therapeutic drugs to improve clinical outcomes for triple-negative breast cancer patients. Metabolic reprogramming may provide promising therapeutic targets for the treatment of triple-negative breast cancer. In this paper, we primarily discuss how triple-negative breast cancer cells reprogram their metabolic phenotype and that of stromal cells in the microenvironment to survive under nutrient-poor conditions. Considering that metastasis and chemoresistance are the main contributors to mortality in triple-negative breast cancer patients, we also focus on the role of metabolic adaption in mediating metastasis and chemoresistance of triple-negative breast cancer tumors.