Kuanoniamine C stimulates bortezomib-induced cell death via suppression of glucose-regulated protein 78 in osteosarcoma

Heat shock proteins as hallmarks of cancer: insights from molecular mechanisms to therapeutic strategies

Heat shock proteins are essential molecular chaperones that play crucial roles in stabilizing protein structures, facilitating the repair or degradation of damaged proteins, and maintaining proteostasis and cellular functions. Extensive research has demonstrated that heat shock proteins are highly expressed in cancers and closely associated with tumorigenesis and progression. The "Hallmarks of Cancer" are the core features of cancer biology that collectively define a series of functional characteristics acquired by cells as they transition from a normal state to a state of tumor growth, including sustained proliferative signaling, evasion of growth suppressors, resistance to cell death, enabled replicative immortality, the induction of angiogenesis, and the activation of invasion and metastasis. The pivotal roles of heat shock proteins in modulating the hallmarks of cancer through the activation or inhibition of various signaling pathways has been well documented. Therefore, this review provides an overview of the roles of heat shock proteins in vital biological processes from the perspective of the hallmarks of cancer and summarizes the small-molecule inhibitors that target heat shock proteins to regulate various cancer hallmarks. Moreover, we further discuss combination therapy strategies involving heat shock proteins and promising dual-target inhibitors to highlight the potential of targeting heat shock proteins for cancer treatment. In summary, this review highlights how targeting heat shock proteins could regulate the hallmarks of cancer, which will provide valuable information to better elucidate and understand the roles of heat shock proteins in oncology and the mechanisms of cancer occurrence and development and aid in the development of more efficacious and less toxic novel anticancer agents.

Kuanoniamine C Suppresses Adipogenesis and White Adipose Tissue Expansion by Modulating Mitochondrial Function

Obesity is characterized by the excessive accumulation of fat to adipose tissue, which is related to abnormal increasing white adipose tissue (WAT) in the body, and it upregulates the risk of multiple diseases. Here, kuanoniamine C, which is a pyridoacridine alkaloid, suppressed the differentiation of pre-adipose cells into white adipocytes via the modulation of mitochondrial function, and inhibited WAT expansion in the early phase of high-fat-diet-induced obesity model. Pharmacological analysis revealed that inhibition of mitochondrial respiratory complex II, which new target of kuanoniamine C, activated reactive oxygen species (ROS)-extracellular signal-regulated kinase (ERK)-β-catenin signaling, and this signaling was antagonized by insulin-, IBMX-, and dexamethasone-induced adipogenesis. Therefore, the kuanoniamine C might prevent abnormal WAT expansion even when eating a diet that is not calorie restricted.

Mechanism and Role of Endoplasmic Reticulum Stress in Osteosarcoma

Osteosarcoma is the most common malignant bone tumor, often occurring in children and adolescents. The etiology of most patients is unclear, and the current conventional treatment methods are chemotherapy, radiotherapy, and surgical resection. However, the sensitivity of osteosarcoma to radiotherapy and chemotherapy is low, and the prognosis is poor. The development of new and useful treatment strategies for improving patient survival is an urgent need. It has been found that endoplasmic reticulum (ER) stress (ERS) affects tumor angiogenesis, invasion, etc. By summarizing the literature related to osteosarcoma and ERS, we found that the unfolded protein response (UPR) pathway activated by ERS has a regulatory role in osteosarcoma proliferation, apoptosis, and chemoresistance. In osteosarcoma, the UPR pathway plays an important role by crosstalk with autophagy, oxidative stress, and other pathways. Overall, this article focuses on the relationship between ERS and osteosarcoma and reviews the potential of drugs or gene targets associated with ERS for the treatment of osteosarcoma.

Mass Spectrometric-Based Proteomics for Biomarker Discovery in Osteosarcoma: Current Status and Future Direction

Due to a lack of novel therapies and biomarkers, the clinical outcomes of osteosarcoma patients have not significantly improved for decades. The advancement of mass spectrometry (MS), peptide quantification, and downstream pathway analysis enables the investigation of protein profiles across a wide range of input materials, from cell culture to long-term archived clinical specimens. This can provide insight into osteosarcoma biology and identify candidate biomarkers for diagnosis, prognosis, and stratification of chemotherapy response. In this review, we provide an overview of proteomics studies of osteosarcoma, indicate potential biomarkers that might be promising therapeutic targets, and discuss the challenges and opportunities of mass spectrometric-based proteomics in future osteosarcoma research.

Screening a novel signature and predicting the immune landscape of metastatic osteosarcoma in children via immune-related lncRNAs

BACKGROUND

The immune microenvironment plays an essential role in osteosarcoma (OSs); however, differences in immune-related long non-coding ribonucleic acids (irlncRNAs) in children with localized OSs and metastatic OSs have not yet been investigated.

METHODS

The clinical data and the transcriptome of OSs were obtained from the Therapeutically Applicable Research to Generate Effective Treatments (TARGET) database, and the immune-related genes were derived from the imported dataset. The correlations between immune-related genes and lncRNAs were examined. Next, the differential expressions of the irlncRNA pairs (IRLPs) in localized OSs and distant metastatic OSs were analyzed, and a prognostic model was constructed based on the significant differentially expressed IRLPs. We also analyzed the association between the IRLPs' signature risk score and the infiltration of the immune cells. Finally, we investigated the correlation between risk score and drug resistance.

RESULTS

Thirty upregulated and 22 downregulated lncRNAs were identified in the localized and metastatic OSs samples. Univariate and multivariate cox regression analyses were undertaken to select 6 lncRNA pairs to establish the prognostic signature, the model was valuable in predicting OSs prognosis. Further, the expression of the finally selected irlncRNAs indicated that VPS9D1-AS1 (P=0.031), AP003086.2 (P=0.041), AL031847.1 (P=0.008), AL020997.3 (P=0.020), AC011444.1 (P=0.025), and AC006449.2 (P=0.003) were significantly upregulated in metastasis patients, but USP27X-AS1 (P=0.046), AL008721.2 (P=0.005), AC002091.1 (P=0.033), and AL118558.4 (P=0.049) were significantly overexpressed in localized patients. The overexpression of AC002091.1 (P=0.038) and AL118558.4 (P=0.004) resulted in better overall survival, but the upregulation of AC011444.1 (P=0.045), AL031847.1 (P=0.020), VPS9D1-AS1 (P=0.039), and AC006449.2 (0.006) led to a poor outcome. Differences in immune cell infiltration indicated that metastatic patients and localized have significant difference of 4 (CD4) T cells (P=0.006), monocytes (P=0.029), activated mast cells (P=0.018), and neutrophils (P=0.026), and a high abundance of activated dendritic cells (P=0.010) and activated mast cells (P=0.049) resulted in poor prognosis. Patients in the high-risk-score group were resistant to axitinib, but sensitive to dasatinib, bortezomib, and cisplatin.

CONCLUSIONS

In the present study, IRLPs were used to construct a novel and practical model for predicting the prognosis of localized and metastatic OSs in children.

LINC00665/miR-379-5p/GRP78 regulates cisplatin sensitivity in gastric cancer by modulating endoplasmic reticulum stress

Acquired resistance to cisplatin (DDP)-based chemotherapy greatly hinders the treatment of gastric cancer (GC). LINC00665 serves as an oncogene in GC. Hence, the current study was designed to investigate the regulatory effects of LINC00665 on DDP-resistance of GC. LINC00665 and miR-379-5p expression levels were detected by real-time quantitative polymerase chain reaction (RT-qPCR) and Glucose regulated protein 78 (GRP78) protein level was measured by western blot assay. Interactions between LINC00665 and miR-379-5p or between miR-379-5p and GRP78 were verified by dual luciferase reporter assay. Cell counting kit 8 (CCK-8) assay and flow cytometry assay respectively determine the proliferative ability and apoptosis of GC cells. Western blot analysis was also performed to detect the protein levels of C/EBP-homologous protein (CHOP), X box binding protein (XBP1) and apoptosis-related proteins. In addition, GRP78 expression was evaluated by immunofluorescence. It was observed that the expression levels of LINC00665 and GRP78 were upregulated, and the expression level of miR-379-5p was downregulated in DDP-sensitive and DDP-resistant GC cell lines. What's more, GRP78 expression and the cell growth inhibition rates of DDP-sensitive and DDP-resistant GC cells had a negative correlation. Additionally, miR-379-5p was a target miRNA of LINC00665, and GRP78 was a target mRNA of miR-379-5p. Functional studies revealed that knockdown of LINC00665 inhibited DDP-resistant GC cell proliferation, induced apoptosis as well as suppressed Endoplasmic reticulum (ER) stress. Mechanistically, knockdown of LINC00665 downregulated GRP78 expression by strengthening miR-379-5p. LINC00665 silencing could overcome DPP-resistance of GC cells by downregulating GRP78 via sponging miR-379-5p, indicating that LINC00665 might be a potential therapeutic target for DDP- resistant GC patients.

ACP-5862 suppresses esophageal squamous cell carcinoma growth through inducing apoptosis via activation of endoplasmic reticulum stress and ROS production

Esophageal squamous cell carcinoma (ESCC) is a common type of human oral malignancy with poor survival. Presently, it is necessary to find new and effective drugs for clinical therapy. This study aimed to identify the potential anti-tumor effects of ACP-5862, a major metabolite of acalabrutinib, on human ESCC progression, and to reveal the underlying mechanisms. Our findings suggested that ACP-5862 treatments markedly reduced the cell proliferation of ESCC cell lines in a time- and dose-dependent manner, while had no significant cytotoxicity to normal cells. Cell cycle arrest in G2/M phase was markedly induced by ACP-5862 in ESCC cells. Furthermore, apoptosis and endoplasmic reticulum (ER) stress were detected in ESCC cells treated with ACP-5862. Intriguingly, ACP-5862-induced apoptotic cell death was partly dependent on ER stress. Moreover, reactive oxygen species (ROS) was greatly triggered in ACP-5862-incubated ESCC cells, which was closely involved in apoptosis and ER stress mediated by ACP-5862. In addition, we showed that the expression of nuclear factor-erythroid 2-related factor-2 (Nrf-2) was considerably reduced in ACP-5862-treated cells. Importantly, ACP-5862 combined with Nrf-2 knockdown could further induce apoptosis and ER stress in ESCC cells compared with the ACP-5862 single group. Animal studies confirmed that repressing Nrf-2 promoted the anti-tumor effect of ACP-5862 on ESCC growth. Taken together, these findings demonstrated that ACP-5862 exerted anti-cancer effects on ESCC through inducing ER stress-mediated apoptosis via the ROS production. Meanwhile, ACP-5862 co-treated with Nrf-2 inhibitors may supply new and effective therapeutic strategies for ESCC treatment in future.