KCNN4 Promotes the Stemness Potentials of Liver Cancer Stem Cells by Enhancing Glucose Metabolism

MiR-301b-3p targets and regulates EBF3 to impact the stem-like phenotype of breast cancer cells through glycolysis

BACKGROUND

Cancer stem cells are essential for the development of tumors, their recurrence, metastasis, and resistance to treatment. Previous studies have shown that the silencing of EBF3 promotes the progression of malignant tumors, but its impact on the stem-like phenotype of tumor cells remains unexplored. Therefore, this work aims to investigate the influence of EBF3 on the stem-like phenotype of breast cancer (BC) cells and its underlying molecular mechanisms.

METHODS

Bioinformatics analysis was utilized to predict EBF3 and miR-301b-3p expression and their binding sites in BC tissues. qRT-PCR was conducted to assess EBF3 and miR-301b-3p expression in BC cells. Cell viability was assessed using CCK-8 assay, while sphere-forming ability was assayed by sphere formation experiments. Western blot analysis was employed to assess the expression of stem cell-related markers and proteins associated with the glycolysis metabolic pathway. ECAR experiments and analysis of glycolysis metabolite production were performed to evaluate cellular glycolysis capacity. Dual-luciferase reporter assays and RIP were utilized to validate the binding relationship between EBF3 and miR-301b-3p.

RESULTS

EBF3 was downregulated in BC tissues and cells, and overexpression of EBF3 repressed the glycolysis capacity of BC cells, thereby suppressing stem-like phenotype. Furthermore, miR-301b-3p was identified as a direct target of EBF3, and its expression was increased in BC. Cell experiments revealed that miR-301b-3p suppressed EBF3 expression, thereby promoting the glycolysis capacity and stem-like phenotype of BC cells.

CONCLUSION

miR-301b-3p enhanced glycolysis and promoted the stem-like phenotype of BC cells by targeting EBF3. These findings can offer new therapeutic approaches for BC.

Expression of KCNN4 in adult-type diffuse gliomas and its correlations with clinicopathological features and patient prognosis

BACKGROUND

The KCa3.1 channel (KCNN4) is extensively investigated as an oncogene in human cancers. The current study aimed to explore the clinicopathological significance of KCNN4 expression in patients with primary adult-type diffuse gliomas.

METHODS

Demographic, RNA-seq, and follow-up data of 477 patients were retrospectively reviewed. Patients were divided into the experimental and validation groups (278 and 199). KCNN4-related genes were determined by Pearson correlation analysis, and enrichment analyses and tumor-infiltrating immune cell assessments were applied to explore the potential mechanisms of KCNN4 involving glioma progression. The Kaplan-Meier method and the Cox regression analysis were used to evaluate the prognostic value of KCNN4 expression.

RESULTS

KCNN4 showed significantly higher expression level in glioblastoma, IDH-wildtype, followed by astrocytoma, IDH-mutant and oligodendroglioma, IDH-mutant and 1p/19q-codeleted (p < 0.001). Enrichment analyses and tumor-infiltrating immune cell assessments suggested that KCNN4 could involve glioma progression through extracellular regulation, affecting immune response, and modulating subcellular trafficking. At last, the Kaplan-Meier analysis showed that high KCNN4 expression was significantly correlated with poor progression-free and overall survival (p < 0.001 for both). While multivariate Cox regression analysis obtained an insignificant result.

CONCLUSIONS

KCNN4 was identified to be overexpressed in glioma cells and its expression level is positively related to tumor malignancy. It potentially participates in glioma biology by affecting extracellular regulation, subcellular trafficking, and immune escape. Additionally, high KCNN4 expression was correlated with poor survival outcomes of patients. The results can shed new light on the mechanisms of glioma progression, and provide a potential therapeutic target for treating gliomas.

Unveiling the link between lactate metabolism and rheumatoid arthritis through integration of bioinformatics and machine learning

Rheumatoid arthritis (RA) is a persistent autoimmune condition characterized by synovitis and joint damage. Recent findings suggest a potential link to abnormal lactate metabolism. This study aims to identify lactate metabolism-related genes (LMRGs) in RA and investigate their correlation with the molecular mechanisms of RA immunity. Data on the gene expression profiles of RA synovial tissue samples were acquired from the gene expression omnibus (GEO) database. The RA database was acquired by obtaining the common LMRDEGs, and selecting the gene collection through an SVM model. Conducting the functional enrichment analysis, followed by immuno-infiltration analysis and protein-protein interaction networks. The results revealed that as possible markers associated with lactate metabolism in RA, KCNN4 and SLC25A4 may be involved in regulating macrophage function in the immune response to RA, whereas GATA2 is involved in the immune mechanism of DC cells. In conclusion, this study utilized bioinformatics analysis and machine learning to identify biomarkers associated with lactate metabolism in RA and examined their relationship with immune cell infiltration. These findings offer novel perspectives on potential diagnostic and therapeutic targets for RA.

IGF2BP2 promotes glycolysis and hepatocellular carcinoma stemness by stabilizing CDC45 mRNA via m6A modification

A growing number of studies have shown the prognostic importance of Cell division cycle protein 45 (CDC45) in hepatocellular carcinoma (HCC). This study aims to investigate the biological function and mechanism of CDC45 in HCC. The differential expression and prognostic significance of CDC45 in HCC and normal tissues were analyzed by bioinformatics. CDC45 was knocked down and the biological effects of CDC45 in HCC in vitro and in vivo were measured. Subsequently, using RNA m6A colorimetry and Methylated RNA Immunoprecipitation (MeRIP), the levels of m6A modification of total RNA and CDC45 were evaluated in cells. RIP was applied to establish that CDC45 and insulin-like growth factor 2 mRNA-binding protein 2 (IGF2BP2) interact. A test using actinomycin D was performed to gauge the stability of the CDC45 mRNA. Furthermore, the regulatory role of IGF2BP2 on CDC45 expression in HCC progression was explored by overexpressing IGF2BP2. High expression of CDC45 was correlated with poor prognosis in HCC patients. Knocking down CDC45 inhibited HCC cell proliferation, migration, invasion, EMT, stemness, and glycolysis, and promoted apoptosis, which was verified through in vitro experiments. Additionally, IGF2BP2 was highly expressed in HCC cells, and it was found to interact with CDC45. Knocking down IGF2BP2 resulted in reduced stability of CDC45 mRNA. Moreover, overexpression of IGF2BP2 promoted HCC cell proliferation, migration, invasion, EMT, stemness, and glycolysis, while inhibiting apoptosis, which was reversed by knocking down CDC45. In general, IGF2BP2 promoted HCC glycolysis and stemness by stabilizing CDC45 mRNA via m6A modification. [Figure: see text].

SKCa- and Kv1-type potassium channels and cancer: Promising therapeutic targets?

Ion channels are transmembrane structures that allow the passage of ions across cell membranes such as the plasma membrane or the membranes of various organelles like the nucleus, endoplasmic reticulum, Golgi apparatus or mitochondria. Aberrant expression of various ion channels has been demonstrated in several tumor cells, leading to the promotion of key functions in tumor development, such as cell proliferation, resistance to apoptosis, angiogenesis, invasion and metastasis. The link between ion channels and these key biological functions that promote tumor development has led to the classification of cancers as oncochannelopathies. Among all ion channels, the most varied and numerous, forming the largest family, are the potassium channels, with over 70 genes encoding them in humans. In this context, this review will provide a non-exhaustive overview of the role of plasma membrane potassium channels in cancer, describing 1) the nomenclature and structure of potassium channels, 2) the role of these channels in the control of biological functions that promotes tumor development such as proliferation, migration and cell death, and 3) the role of two particular classes of potassium channels, the SKCa- and Kv1- type potassium channels in cancer progression.

Potassium channels as novel molecular targets in hepatocellular carcinoma (Review)

Hepatocellular carcinoma (HCC) poses a serious health burden worldwide. It is often not diagnosed until the patient is at an advanced stage of the disease, when treatment options are limited and the prognosis is poor. Therefore, novel treatment strategies are urgently required. Potassium (K+) channels have an important role in HCC, including regulating the proliferation, migration, invasion and drug resistance of HCC cells. The aim of the present review was therefore to survey the relevant publications that have investigated K+ channels not only as markers for the early diagnosis of HCC, but also as potential therapeutic targets for the treatment of HCC. Several of these channels have been indicated to be the sites of action for natural products previously known to inhibit HCC; however, more systematic studies are required to determine which K+ channels may be utilized for the clinical treatment of HCC, particularly in the advanced stages of the disease and in cases where patients are resistant to the existing drugs.

FOXM1/NCAPH activates glycolysis to promote colon adenocarcinoma stemness and 5-FU resistance

Chemotherapy using 5-fluorouracil (5-FU) is currently considered the most effective treatment for advanced colon adenocarcinoma (COAD). However, drug resistance remains a major obstacle in treating COAD. Non-SMC condensin I complex subunit H ( NCAPH ) is known to have a certain impact on the development of COAD, but its precise involvement in the mechanism of 5-FU resistance has not been demonstrated. Bioinformatics analysis was utilized to assay the expression of NCAPH and Forkhead box M1 ( FOXM1 ) in COAD tumor tissues, which was then verified in COAD cell lines. The resistance of COAD cells to 5-FU was measured by CCK-8 assay, stemness was tested by cell sphere formation assay, and glycolysis ability was measured by cellular energy analysis metabolism. Chromatin Immunoprecipitation and dual-luciferase reporter assays were done to confirm the specific interaction between FOXM1 and NCAPH . The expression levels of FOXM1 and NCAPH were significantly upregulated in COAD tissues and cells, and they were involved in regulating the glycolytic signaling pathway. Inhibition of the glycolytic pathway could reverse the effect of NCAPH overexpression on COAD stemness and resistance. FOXM1 was identified as a transcription factor of NCAPH , and it regulated COAD glycolysis, cell stemness, and 5-FU resistance by activating NCAPH expression. FOXM1-mediated upregulation of NCAPH expression promoted COAD cell stemness and resistance via the glycolytic pathway. This study provides a possible mechanism for the FOXM1/NCAPH axis in the glycolytic pathway, cell stemness, and resistance in COAD.

Potassium Channels, Glucose Metabolism and Glycosylation in Cancer Cells

Potassium channels emerge as one of the crucial groups of proteins that shape the biology of cancer cells. Their involvement in processes like cell growth, migration, or electric signaling, seems obvious. However, the relationship between the function of K+ channels, glucose metabolism, and cancer glycome appears much more intriguing. Among the typical hallmarks of cancer, one can mention the switch to aerobic glycolysis as the most favorable mechanism for glucose metabolism and glycome alterations. This review outlines the interconnections between the expression and activity of potassium channels, carbohydrate metabolism, and altered glycosylation in cancer cells, which have not been broadly discussed in the literature hitherto. Moreover, we propose the potential mediators for the described relations (e.g., enzymes, microRNAs) and the novel promising directions (e.g., glycans-orinented drugs) for further research.

Potassium channels, tumorigenesis and targeted drugs

Potassium channels play an important role in human physiological function. Recently, various molecular mechanisms have implicated abnormal functioning of potassium channels in the proliferation, migration, invasion, apoptosis, and cancer stem cell phenotype formation. Potassium channels also mediate the association of tumor cells with the tumor microenvironment. Meanwhile, potassium channels are important targets for cancer chemotherapy. A variety of drugs exert anti-cancer effects by modulating potassium channels in tumor cells. Therefore, there is a need to understand how potassium channels participate in tumor development and progression, which could reveal new, novel targets for cancer diagnosis and treatment. This review summarizes the roles of voltage-gated potassium channels, calcium-activated potassium channels, inwardly rectifying potassium channels, and two-pore domain potassium channels in tumorigenesis and the underlying mechanism of potassium channel-targeted drugs. Therefore, the study lays the foundation for rational and effective drug design and individualized clinical therapeutics.

A prospective diagnostic and prognostic biomarker for hepatocellular carcinoma that functions in glucose metabolism regulation: Solute carrier family 37 member 3

Hepatocellular carcinoma (HCC) is the most common type of liver cancer. Due to the insidious onset of HCC, early diagnosis is relatively difficult. HCC also exhibit strong resistance to first-line therapeutic drugs. Therefore, novel precise diagnostic and prognostic biomarkers for HCC are urgently needed. We employed a combination methods of bioinformatic analysis, cell functional experiments in vitro and a xenograft tumour model in vivo to systematically investigate the role of solute carrier family 37 member 3 (SLC37A3) in HCC progression. First, bioinformatic analysis demonstrated that SLC37A3 expression was significantly increased in HCC tissues compared with normal tissues. SLC37A3 expression was also associated with tumour stages and various clinical and pathological features. Similar trends in SLC37A3 expression levels were verified in HCC cells and by using IHC experiments. Next, survival analysis showed that the overall, 1-year, 3-year and 5-year survival rates were decreased in HCC patients with high SLC37A3 expression compared with HCC patients low SLC37A3 expression. Xenograft tumour experiments also suggested that SLC37A3 knockdown significantly inhibited HCC tumourigenesis in vivo. Cell functional experiments suggested that SLC37A3 knockdown inhibited HCC cell proliferation and metastasis, but promoted apoptosis. Furthermore, RNA-seq analysis of SLC37A3-knockdown HCC cells indicated that the type 1 diabetes mellitus (T1DM)-related signalling pathway was significantly altered. The expression levels of insulin secretion-related and glycolysis/gluconeogenesis-related genes were also altered, suggesting that SLC37A3 might be involved in the regulation of glucose homeostasis. In summary, SLC37A3 represents a prospective diagnostic and prognostic biomarker for HCC that functions in glucose metabolism regulation.

A potent ion channel blocker, hydroquinidine, exhibits strong anti-cancer activity on colon, pancreatic, and hepatocellular cancer cells

BACKGROUND

Despite recent advances in drug discovery, cancer is still one of the most lethal health problems worldwide. In most cases, standard therapy methods and multi-modal treatments fail, and new therapeutic approaches are required. Ion channels are essential in multiple cellular processes regulating cell division, differentiation, and death. Recent studies on ion-channel modulators emphasize their potential to suppress tumor growth. In that regard, we reasoned that an underinvestigated potassium channel modulator, Hydroquinidine (HQ), may exhibit an anti-carcinogenic activity.

METHODS AND RESULTS

HQ's potential as an anti-neoplastic compound was examined using colony formation assay, wound healing assay, soft agar assay, and Annexin-V assay in the colon, pancreatic, and hepatocellular carcinomas. Our findings unveiled a remarkable anti-cancer activity of HQ by decreasing colony-forming ability, migration capacity, tumorigenicity, and proliferation and stimulating cellular death. HQ significantly reduced the formed colonies and tumorigenicity for all cells. It displayed a significant anti-migrative effect on hepatocellular carcinoma cells and promoted apoptosis in pancreatic and liver cancer cells. The altered gene expression profile upon HQ treatment was in accordance with observed cellular effects. Cells incubated with HQ downregulated the genes acting in cell division and survival, whereas the expression level of genes functioning in cell cycle arrest and apoptosis was elevated.

CONCLUSION

Our data indicate HQ's competency to limit cancer growth and suggest its utilization as a novel potent anti-carcinogenic agent. Future studies are necessary to provide new insights into the HQ action mechanism and to evaluate its capacity in in-vivo.

Single-cell pair-wise relationships untangled by composite embedding model

In multicellular organisms, cell identity and functions are primed and refined through interactions with other surrounding cells. Here, we propose a scalable machine learning method, termed SPRUCE, which is designed to systematically ascertain common cell-cell communication patterns embedded in single-cell RNA-seq data. We applied our approach to investigate tumor microenvironments consolidating multiple breast cancer datasets and found seven frequently observed interaction signatures and underlying gene-gene interaction networks. Our results implicate that a part of tumor heterogeneity, especially within the same subtype, is better understood by differential interaction patterns rather than the static expression of known marker genes.

The Emerging Role of Tumor Microenvironmental Stimuli in Regulating Metabolic Rewiring of Liver Cancer Stem Cells

Primary liver cancer (PLC) is one of the most devastating cancers worldwide. Extensive phenotypical and functional heterogeneity is a cardinal hallmark of cancer, including PLC, and is related to the cancer stem cell (CSC) concept. CSCs are responsible for tumor growth, progression, relapse and resistance to conventional therapies. Metabolic reprogramming represents an emerging hallmark of cancer. Cancer cells, including CSCs, are very plastic and possess the dynamic ability to constantly shift between different metabolic states depending on various intrinsic and extrinsic stimuli, therefore amplifying the complexity of understanding tumor heterogeneity. Besides the well-known Warburg effect, several other metabolic pathways including lipids and iron metabolism are altered in PLC. An increasing number of studies supports the role of the surrounding tumor microenvironment (TME) in the metabolic control of liver CSCs. In this review, we discuss the complex metabolic rewiring affecting liver cancer cells and, in particular, liver CSCs. Moreover, we highlight the role of TME cellular and noncellular components in regulating liver CSC metabolic plasticity. Deciphering the specific mechanisms regulating liver CSC-TME metabolic interplay could be very helpful with respect to the development of more effective and innovative combinatorial therapies for PLC treatment.

IKCa channels control breast cancer metabolism including AMPK-driven autophagy

Ca²⁺-activated K⁺ channels of intermediate conductance (IK) are frequently overexpressed in breast cancer (BC) cells, while IK channel depletion reduces BC cell proliferation and tumorigenesis. This raises the question, of whether and mechanistically how IK activity interferes with the metabolic activity and energy consumption rates, which are fundamental for rapidly growing cells. Using BC cells obtained from MMTV-PyMT tumor-bearing mice, we show that both, glycolysis and mitochondrial ATP-production are reduced in cells derived from IK-deficient breast tumors. Loss of IK altered the sub-/cellular K⁺- and Ca²⁺- homeostasis and mitochondrial membrane potential, ultimately resulting in reduced ATP-production and metabolic activity. Consequently, we find that BC cells lacking IK upregulate AMP-activated protein kinase activity to induce autophagy compensating the glycolytic and mitochondrial energy shortage. Our results emphasize that IK by modulating cellular Ca²⁺- and K⁺-dynamics contributes to the remodeling of metabolic pathways in cancer. Thus, targeting IK channel might disturb the metabolic activity of BC cells and reduce malignancy.