SIAH1 ubiquitination-modified HMGCR inhibits lung cancer progression and promotes drug sensitivity through cholesterol synthesis

Targeting lipid metabolism via nanomedicine: A prospective strategy for cancer therapy

Lipid metabolism has been increasingly recognized to play an influencing role in tumor initiation, progression, metastasis, and therapeutic drug resistance. Targeting lipid metabolic reprogramming represents a promising therapeutic strategy. Despite their structural complexity and poor targeting efficacy, lipid-metabolizing drugs, either used alone or in combination with chemotherapeutic agents, have been employed in clinical practice. The advent of nanotechnology offers new approaches to enhancing therapeutic effects, includingthe targeted delivery and integration of lipid metabolic reprogramming with chemotherapy, photodynamic therapy (PDT), and immunotherapy. The integrated nanoformulation, nanomedicine, could significantly advance the field of lipid metabolism therapy. In this review, we will briefly introduce the concept of cancer lipid metabolism reprogramming, then elaborate the latest advances in engineered nanomedicine for targeting lipid metabolism during cancer treatment, and finally provide our insights into future perspectives of nanomedicine for interference with lipid metabolism in the tumor microenvironment.

Role of ubiquitination-driven metabolisms in oncogenesis and cancer therapy

Ubiquitination represents one of the most critical post-translational modifications, comprising a multi-stage enzyme process that plays a pivotal role in a myriad of cellular biological activities. The deregulation of the processes of ubiquitination and deubiquitination is associated with the development of cancers and other diseases. This typescript reviews the impact of ubiquitination on metabolic processes, elucidating the regulatory functions of ubiquitination on pivotal enzymes within metabolic pathways in pathological contexts. It underscores the role of ubiquitination-driven metabolism disorders in the etiology of cancers, and oncogenesis, and highlights the potential therapeutic efficacy of targeting ubiquitination-driven enzymes in cancer metabolism, their combination with immune checkpoint inhibitors, and their clinical applications.

IGF2BP3/ESM1/KLF10/BECN1 positive feedback loop: a novel therapeutic target in ovarian cancer via lipid metabolism reprogramming

Ovarian cancer (OC) is often detected at an advanced stage and has a high recurrence rate after surgery or chemotherapy. Thus, it is essential to develop new strategies for OC treatment. This study tended to investigate the effects of endothelial cell-specific molecule 1 (ESM1) in OC. The impact of ESM1 on lipid metabolism was investigated through the regulation of ESM1 expression. Differential genes regulated by ESM1 were screened by mRNA sequencing. The role of autophagy in ESM1 regulation on lipid metabolism was explored using autophagy inhibitor chloroquine (CQ). Co-IP, dual-luciferase reporter assay, actinomycin D treatment assay, and others were used to analyze the mechanism of ESM1 regulation on lipid metabolism. The xenograft mouse model was constructed to explore the impact of ESM1 regulation on OC development. The regulatory mechanism of ESM1 in OC patient samples was verified by using microarray analysis and the Log-rank (Mantel-Cox) test. After ESM1 silencing, cholesterol synthesis decreased and lipolysis increased. mRNA sequencing revealed that ESM1 regulation on lipid metabolism was related to Beclin 1 (BECN1). In vitro experiments, ESM1 inhibited lipolysis by suppressing BECN1-mediated autophagy. BECN1 expression was regulated by the transcription factor Kruppel-like factor 10 (KLF10). The competitive binding between BECN1 and HSPA5 promoted the ubiquitination degradation of HMGCR, thereby inhibiting cholesterol production. The intervention experiment with exogenous cholesterol showed a positive correlation between m6A reader IGF2BP3 expression and cholesterol content. Mechanistically, IGF2BP3 regulated the stability of ESM1 mRNA. In vivo experiments, ESM1 modified by m6A methylation promoted cholesterol synthesis and inhibited lipolysis. High expression of ESM1 predicted poor prognosis in OC patients. ESM1 regulated lipid metabolism through IGF2BP3/ESM1/KLF10/BECN1 positive feedback, which was a promising target for OC treatment.

The Role of Cholesterol Metabolism and Its Regulation in Tumor Development

BACKGROUND

Within the tumor microenvironment, tumor cells undergo metabolic reprogramming of cholesterol due to intrinsic cellular alterations and changes in the extracellular milieu. Furthermore, cholesterol reprogramming within this microenvironment influences the immune landscape of tumors, facilitating immune evasion and consequently promoting tumorigenesis. These biological changes involve modifications in numerous enzymes associated with cholesterol uptake and synthesis, including NPC1L1, SREBP, HMGCR, SQLE, and PCSK9.

REVIEW

This review systematically summarizes the role of cholesterol metabolism and its associated enzymes in cancer progression, examines the mechanisms through which dysregulation of cholesterol metabolism affects immune cells within the tumor microenvironment, and discusses recent advancements in cancer therapies that target cholesterol metabolism.

CONCLUSION

Targeting cholesterol metabolism-related enzymes can inhibit tumor growth, reshape immune landscapes, and rejuvenate antitumor immunity, offering potential therapeutic avenues in cancer treatment.

Targeting lipid metabolism of macrophages: A new strategy for tumor therapy

BACKGROUND

Lipid metabolism has been implicated in a variety of normal cellular processes and strongly related to the development of multiple diseases, including tumor. Tumor-associated macrophage (TAM) has emerged as a crucial regulator in tumorigenesis and promising target for tumor treatment.

AIM OF REVIEW

A thorough understanding of TAM lipid metabolism and its value in tumorigenesis may provide new ideas for TAM-based anti-tumor therapy. Key scientific concepts of review: TAMs can be divided into two main types, M1-like TAMs and M2-like TAMs, which play anti-tumor and pro-tumor functions in tumor occurrence and development, respectively. Accumulating evidence has shown that lipid metabolic reprogramming, including fatty acid uptake and utilization, cholesterol expulsion, controls the polarization of TAMs and affects the tumorgenesis. These advances in uncovering the intricacies of lipid metabolism and TAMs have yielded new insights on tumor development and treatment. In this review, we aim to provide an update on the current understanding of the lipid metabolic reprogramming made by TAMs to adapt to the harsh tumor microenvironment (TME). In particular, we emphasize that there is complex lipid metabolism connections between TAMs and distinct tumors, which influences TAM to bias from M1 to M2 phenotype in tumor progression, and ultimately promotes tumor occurrence and development. Finally, we discuss the existing issues on therapeutic strategies by reprogramming TAMs based on lipid metabolism regulation (or increasing the ratio of M1/M2-like TAMs) that could be applied in the future to clinical tumor treatment.

Taxus chinensis var. mairei (Lemée et Lévl) Cheng et L.K. Fu overcomes the resistance to osimertinib in EGFR-mutant non-small-cell lung cancer via suppression of ERK1/2-related cholesterol biosynthesis

ETHNOPHARMACOLOGICAL RELEVANCE

Acquired resistance to osimertinib limits its clinical efficacy in non-small cell lung cancer (NSCLC) with EGFR mutations. The widespread recognition of Taxus chinensis var. Mairei (Lemée et Lévl) Cheng et L.K. Fu (Chinese yew) as a natural anti-cancer medication is well-established. However, the specific contribution of Taxus chinensis var. Mairei (Lemée et Lévl) Cheng et L.K. Fu in addressing resistance to osimertinib is still uncertain.

AIM OF THE STUDY

Based on the biological behaviors and lipid metabolism, we investigated whether aqueous extract of Taxus chinensis var. Mairei (Lemée et Lévl) Cheng et L.K. Fu (AETC) could enhance the antitumor effect of osimertinib in NSCLC with an investigation on the precise mechanisms.

MATERIALS AND METHODS

The effect of AETC on enhancing osimertinib sensitivity was assessed via cell viability measurements, levels of reactive oxygen species (ROS), apoptosis, and lipid levels. Western blotting was used to verify the mechanisms of AETC responsible for overcoming the resistance to osimertinib via ERK1/2 overexpression and knockdown models. In vivo validation was conducted using subcutaneous xenografts from osimertinib-resistant cells in nude mice.

RESULTS

Osimertinib-resistant cells exhibited altered cholesterol biosynthesis, which was induced by ERK1/2 activation. The combination of AETC and osimertinib can synergistically decrease the levels of ROS in cells, enhance apoptosis, and inhibit the growth of osimertinib-resistant cells. Mechanistic experiments demonstrated that AETC can downregulate the key regulators of cholesterol biosynthesis by regulating ERK1/2, inhibiting the endogenous synthesis rate of cholesterol, and suppressing the level of lipids in osimertinib-resistant cells and xenograft tumors when combined with osimertinib, ultimately reversing resistance to osimertinib.

CONCLUSIONS

The resistance to osimertinib is significantly influenced by cholesterol biosynthesis, highlighting its pivotal role in this context. AETC can enhance osimertinib sensitivity via ERK/SREBP-2/HMGCR-mediated cholesterol biosynthesis. These results provide a promising therapeutic target and potential treatment option for resistance to osimertinib.

Advances of E3 ligases in lung cancer

Lung cancer is a leading cause of cancer-related death, and the most common type of lung cancer is non-small cell lung cancer, which accounts for approximately 85 % of lung cancer diagnoses. Recent studies have revealed that ubiquitination acts as a crucial part of the development and progression of lung cancer. The E1-E2-E3 three-enzyme cascade has a core function in ubiquitination, so targeted adjustments of E3 ligases could be used in lung cancer treatment. Hence, we elucidate research advances in lung cancer-related E3 ligases by briefly describing the structure and categorization of E3 ligases. Here, we provide a detailed review of the mechanisms by which lung cancer-related E3 ligases modify substrate proteins and regulate signaling pathways to facilitate or suppress cancer progression. We hope to show a new perspective on targeted precision therapy for lung cancer.