Platelet isoform of phosphofructokinase accelerates malignant features in breast cancer

ATPase copper transporting beta attenuates malignant features with high expression as an indicator of favorable prognosis in breast cancer

BACKGROUND

ATPase copper transporting beta (ATP7B) functions as a copper-transporting ATPase that ejects copper from cells. Although high expression of ATP7B has been reported to increase cisplatin resistance, its role in breast cancer (BC) remains unclear. This study aimed to elucidate the function of ATP7B in BC cells and its significance in patients with BC.

METHODS

The mRNA and protein expression levels of ATP7B were evaluated in BC and non-cancerous mammary cell lines. Polymerase chain reaction (PCR) array analysis was conducted to determine the correlation between ATP7B and 84 cancer-related genes. ATP7B knockdown was performed using small interfering RNA, and cell proliferation, invasiveness, and migration were analyzed. The associations between the mRNA and protein expression of ATP7B and clinicopathological factors were also investigated in 156 patients with BC.

RESULTS

ATP7B was found to be highly expressed in estrogen receptor-positive and human epidermal growth factor receptor 2-positive BC cell lines. PCR array analysis revealed a significant correlation between the expression level of ATP7B and those of cadherin 1, estrogen receptor 1, and MET proto-oncogene. ATP7B knockdown significantly increased the proliferation, invasiveness, and migration of MDA-MB-361 and MDA-MB-415 cells. Patients with high ATP7B expression at the mRNA and protein levels experienced favorable prognoses. In addition, ATP7B expression level was identified as an independent prognostic factor in multivariate analysis.

CONCLUSIONS

ATP7B is involved in promoting anti-cancer activities of tumor suppressors in BC cells across different subtypes and is considered a prognostic marker for BC.

E3 ubiquitin ligase SYVN1 as a promising therapeutic target for diverse human diseases

Numerous studies conducted in recent years indicate that mammalian E3 ubiquitin ligases serve as key regulators in the maintenance of cellular homeostasis by targeting the ubiquitination of substrate proteins and activating downstream signaling pathways. SYVN1, an E3 ubiquitin ligase, is characterized by its significant functions in regulating various biological processes, including molecular mechanisms related to gene expression, signaling pathways, and cell death, among others. Consequently, SYVN1 plays a crucial role in both normal human physiology and the pathogenesis of various diseases, such as oncogenesis, cardiovascular disorders, immune regulation, skeletal anomalies, and neurological diseases. This review synthesizes recent findings regarding the physiological and pathophysiological roles of SYVN1, offering new insights into potential strategies for the prevention and treatment of human diseases, as well as suggesting avenues for future drug development. In this Review, we summarize the latest findings regarding the physiological and pathophysiological roles of SYVN1, elucidating the mechanisms by which SYVN1 can regulate the progression of various diseases in humans. These important findings provide new avenues for further investigation of SYVN1 protein, new insights into potential strategies to prevent and treat human diseases, and new directions for future drug development.

Biomimetic Synthesis and Chemical Proteomics Reveal the Mechanism of Action and Functional Targets of Phloroglucinol Meroterpenoids

Natural products perennially serve as prolific sources of drug leads and chemical probes, fueling the development of numerous therapeutics. Despite their scarcity, natural products that modulate protein function through covalent interactions with lysine residues hold immense potential to unlock new therapeutic interventions and advance our understanding of the biological processes governed by these modifications. Phloroglucinol meroterpenoids constitute one of the most expansive classes of natural products, displaying a plethora of biological activities. However, their mechanism of action and cellular targets have, until now, remained elusive. In this study, we detail the concise biomimetic synthesis, computational mechanistic insights, physicochemical attributes, kinetic parameters, molecular mechanism of action, and functional cellular targets of several phloroglucinol meroterpenoids. We harness synthetic clickable analogues of natural products to probe their disparate proteome-wide reactivity and subcellular localization through in-gel fluorescence scanning and cell imaging. By implementing sample multiplexing and a redesigned lysine-targeting probe, we streamline a quantitative activity-based protein profiling, enabling the direct mapping of global reactivity and ligandability of proteinaceous lysines in human cells. Leveraging this framework, we identify numerous lysine-meroterpenoid interactions in breast cancer cells at tractable protein sites across diverse structural and functional classes, including those historically deemed undruggable. We validate that phloroglucinol meroterpenoids perturb biochemical functions through stereoselective and site-specific modification of lysines in proteins vital for breast cancer metabolism, including lipid signaling, mitochondrial respiration, and glycolysis. These findings underscore the broad potential of phloroglucinol meroterpenoids for targeting functional lysines in the human proteome.

Hitting the Sweet Spot: How Glucose Metabolism Is Orchestrated in Space and Time by Phosphofructokinase-1

Glycolysis is the central metabolic pathway across all kingdoms of life. Intensive research efforts have been devoted to understanding the tightly orchestrated processes of converting glucose into energy in health and disease. Our review highlights the advances in knowledge of how metabolic and gene networks are integrated through the precise spatiotemporal compartmentalization of rate-limiting enzymes. We provide an overview of technically innovative approaches that have been applied to study phosphofructokinase-1 (PFK1), which represents the fate-determining step of oxidative glucose metabolism. Specifically, we discuss fast-acting chemical biology and optogenetic tools that have delineated new links between metabolite fluxes and transcriptional reprogramming, which operate together to enact tissue-specific processes. Finally, we discuss how recent paradigm-shifting insights into the fundamental basis of glycolytic regulatory control have shed light on the mechanisms of tumorigenesis and could provide insight into new therapeutic vulnerabilities in cancer.

Role of Glucose Metabolic Reprogramming in Breast Cancer Progression and Drug Resistance

The involvement of glucose metabolic reprogramming in breast cancer progression, metastasis, and therapy resistance has been increasingly appreciated. Studies in recent years have revealed molecular mechanisms by which glucose metabolic reprogramming regulates breast cancer. To date, despite a few metabolism-based drugs being tested in or en route to clinical trials, no drugs targeting glucose metabolism pathways have yet been approved to treat breast cancer. Here, we review the roles and mechanisms of action of glucose metabolic reprogramming in breast cancer progression and drug resistance. In addition, we summarize the currently available metabolic inhibitors targeting glucose metabolism and discuss the challenges and opportunities in targeting this pathway for breast cancer treatment.

PFKP: More than phosphofructokinase

Phosphofructokinase (PFK) is one of the key enzymes that functions in glycolysis. Studies show that PFKP regulates cell proliferation, apoptosis, autophagy, cell migration/metastasis, and stemness through glycolysis and glycolysis-independent functions. PFKP performs its function not only in the cytoplasm, but also at the cell membrane, on the mitochondria, at the lysosomal membrane, and in the nucleus. The functions of PFKP are extensively studied in cancer cells. PFKP is also highly expressed in certain immune cells; nevertheless, the study of the PFKP's role in immune cells is limited. In this review, we summarize how the expression and activity of PFKP are regulated in cancer cells. PFKP may be applied as a prognostic marker due to its overexpression and significant functions in cancer cells. As such, specifically targeting/inhibiting PFKP may be a critical and promising strategy for cancer therapy.

Energy metabolism pathways in breast cancer progression: The reprogramming, crosstalk, and potential therapeutic targets

Breast cancer (BC) is a malignant tumor that seriously endangers health in women. BC, like other cancers, is accompanied by metabolic reprogramming. Among energy metabolism-related pathways, BC exhibits enhanced glycolysis, tricarboxylic acid (TCA) cycle, pentose phosphate pathway (PPP), glutamate metabolism, and fatty acid metabolism activities. These pathways facilitate the proliferation, growth and migration of BC cells. The progression of BC is closely related to the alterations in the activity or expression level of several metabolic enzymes, which are regulated by the intrinsic factors such as the key signaling and transcription factors. The metabolic reprogramming in the progression of BC is attributed to the aberrant expression of the signaling and transcription factors associated with the energy metabolism pathways. Understanding the metabolic mechanisms underlying the development of BC will provide a druggable potential for BC treatment and drug discovery.

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

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