RPL15 promotes hepatocellular carcinoma progression via regulation of RPs-MDM2-p53 signaling pathway

Clinical significances of RPL15 gene expression in circulating tumor cells of patients with breast cancer

The preferred biomarkers for evaluating the outcomes of patients with breast cancer (BC) remain poorly understood. The present study aimed to investigate the predictive roles of circulating tumor cells (CTCs) and ribosomal protein L 15 (RPL15) expression in the prognosis of patients with BC. A total of 170 patients were included in the present study, all of whom were female. BC was diagnosed by combining clinical features, imaging and pathological findings. CanPatrol™ technology and triple color in situ RNA hybridization were used to detect CTC subtypes and RPL15 gene expression levels. CTCs were classified into epithelial CTCs, mesenchymal CTCs (MCTCs), and hybrid CTCs (HCTCs) according to cellular surface markers. Risk factors for recurrence and metastasis were validated by a multivariate COX regression model. Kaplan-Meier survival curves were used to determine the progression-free survival (PFS) of patients. The results showed that patients with advanced tumor-node-metastasis stage and triple negative BC had high MCTCs, HCTCs and RPL15 levels (P<0.05). Furthermore, the multivariate COX regression analysis revealed that MCTCs, HCTCs, HER2+ and positive RPL15 gene expression were key factors for recurrence and metastasis of patients (P<0.05). The PFS of patients with >2 MCTCs/5 ml blood, >5 HCTCs/5 ml blood, and positive RPL15 gene expression in CTCs were significantly shorter than that of patient with 2 MCTCs, 5 HCTCs, and negative RPL15 gene expression in CTCs (P<0.05). By contrast, the PFS of patients with positive HER2 also was significantly shorter than that of patients with negative HER2. Overall, the present data indicated that the PFS of patients with BC with >2 MCTC or >5 HCTCs, and positive RPL15 gene expression was shorter than that of those with 2 MCTCs or 5 HCTCs, and negative RPL15 gene expression. Additionally, the prognosis of patients with BC with negative HER2 is more favorable than the prognosis of patients with positive HER2 expression.

EIF2B5 promotes malignant progression of hepatocellular carcinoma by activating the PI3K/AKT signaling pathway through targeting RPL6

Hepatocellular carcinoma (HCC) is a highly aggressive malignancy with limited treatment options and poor prognosis. In this study, we demonstrated the critical role of EIF2B5 in driving HCC progression. We found EIF2B5 expression is significantly upregulated in HCC tumor tissues in several bioinformatics datasets, including The Cancer Genome Atlas, and that high expression of EIF2B5 predicts poor prognosis for HCC patients. Through a series of in vitro cell biology experiments, we found that EIF2B5 knockdown significantly attenuated Hep3B and HepG2 proliferation, migration, and invasion and increased cell cycle arrest, whereas EIF2B5 overexpression promoted HCC progression. Through mass spectrometry and immunoprecipitation validation, we found that EIF2B5 directly interacted with RPL6 and that when EIF2B5 was overexpressed in HCC cells, it promoted the expression of the downstream protein RPL6, which was able to activate the phosphatidylinositol kinase (PI3K)/serine-threonine kinase (AKT)/mammalian target of rapamycin (mTOR) pathway and thereby increase the proliferation and invasion ability of HCC cell lines, as verified by second-generation sequencing analysis and western blot. We further verified these findings using the mouse ectopic tumor assay, and the results showed that EIF2B5 knockdown significantly inhibited tumor progression in HCC mice. The present study suggests that EIF2B5 promotes malignant progression of HCC by interacting with RPL6 and activating the PI3K/AKT/mTOR signaling pathway and may serve as a potential target for the treatment of HCC.

Ribosomal Proteins as Exosomal Cargo: Random Passengers or Crucial Players in Carcinogenesis?

Many ribosomal proteins (RPs) have functions beyond their canonical role as constituents of the ribosome. They often relate to human pathologies, primarily, to carcinogenesis, and the expression of specific RPs is considerably changed in malignant cells. On the other hand, extracellular vesicles (including exosomes), which provide intercellular communication by transporting specific molecular cargo from donor to recipient cells, often contain specific sets of RPs. Thus, one can assume that oncogenic properties of RPs can be transferred from one cell to another by exosomes. Such kind transfer has been already documented with RPS3 and gastric cancer cells. However, it remains largely unclear how widespread is the above effect and to which extent it contributes to the tumor progression and metastasis. To shed light on this issue, a comparative analysis of the sets of RPs found in exosomes and of the available data on oncogenic properties of these proteins is conducted.

Ribosomal proteins in hepatocellular carcinoma: mysterious but promising

Ribosomal proteins (RPs) are essential components of ribosomes, playing a role not only in ribosome biosynthesis, but also in various extra-ribosomal functions, some of which are implicated in the development of different types of tumors. As universally acknowledged, hepatocellular carcinoma (HCC) has been garnering global attention due to its complex pathogenesis and challenging treatments. In this review, we analyze the biological characteristics of RPs and emphasize their essential roles in HCC. In addition to regulating related signaling pathways such as the p53 pathway, RPs also act in proliferation and metastasis by influencing cell cycle, apoptosis, angiogenesis, and epithelial-to-mesenchymal transition in HCC. RPs are expected to unfold new possibilities for precise diagnosis and individualized treatment of HCC.

Glycolytic pathway analysis and gene expression profiles of combination of aloe vera and paclitaxel on non-small cell lung cancer and breast cancer

The purpose of this study is to enhance the effectiveness of known anticancer medications using natural compounds. The study investigated the impact of combining AVE with PAX on non-small cell lung cancer (A549) and breast cancer (MCF7). In this study, A549 and MCF7 cells were treated with PAX (5 μM), AVE (24 μg/mL), and a combination of PAX and AVE (5 μM + 24 μg/mL). The glucose consumption rates of the cells were determined by extracellular acidification rate (ECAR) thanks to the SeaHorse XFe24 instrument. In addition, gene expression profiles were determined by performing Total RNA sequencing with the Novaseq 6000 instrument. Finally, the expressions of GAPDH, BAX, and BCL-2 genes involved in the apoptotic pathway were detected by RT-qPCR. The combined application of PAX and AVE reduced the ECAR value in both cell lines. According to the RT-qPCR results, the expression level of the apoptotic gene BAX increased in both cell lines (p < 0.05). Total RNA sequencing revealed that the combination effects of PAX and AVE play a role in the ribosome mechanism, thereby affecting the protein translation system in MCF7 while apoptosis and cell cycle have come to the forefront in A549.

Analysis of the Anticancer Mechanism of OR3 Pigment from Streptomyces coelicolor JUACT03 Against the Human Hepatoma Cell Line Using a Proteomic Approach

This study assessed OR3 pigment, derived from Streptomyces coelicolor JUACT03, for its anticancer potential on HepG2 liver cancer cells and its safety on HEK293 normal cells. OR3 induced apoptosis and inhibited HepG2 cell proliferation, confirmed by caspase activation, Sub-G1 phase cell cycle arrest, and reduced colony formation. Proteomic analysis revealed altered expression of proteins associated with ribosomal function, mRNA processing, nuclear transport, proteasome activity, carbohydrate metabolism, chaperone function, histone regulation, and vesicle-mediated transport. Downregulation of proteins in MAPKAP kinase1, EIF2, mTOR, and EIF4 pathways contributed to apoptosis and cell cycle arrest. Changes in c-MYC, FUBP1 target proteins and upregulation of Prohibitin-1 (PHB1) were also noted. Western blot analysis supported alterations in eIF2, mTOR, and RAN pathways, including downregulation of RAB 5, c-MYC, p38, MAPK1, and MAPK3. OR3 exhibited significant anti-angiogenic activity in the in ovo CAM assay. In summary, OR3 demonstrated strong anticancer effects, inducing apoptosis, hindering proliferation, and displaying antiangiogenic properties. These findings highlight OR3's potential as an anticancer drug candidate, warranting further in vivo exploration.

Identification and validation of autophagy-related genes in primary open-angle glaucoma

BACKGROUND

As the most common type of glaucoma, the etiology of primary open-angle glaucoma (POAG) has not been unified. Autophagy may affect the occurrence and development of POAG, while the specific mechanism and target need to be further explored.

METHODS

The GSE27276 dataset from the Gene Expression Omnibus (GEO) database and the autophagy gene set from the GeneCards database were selected to screen differentially expressed autophagy-related genes (DEARGs) of POAG. Hub DEARGs were selected by constructing protein-protein interaction (PPI) networks and utilizing GSE138125 dataset. Subsequently, immune cell infiltration analysis, genome-wide association study (GWAS) analysis, gene set enrichment analysis (GSEA) and other analyses were performed on the hub genes. Eventually, animal experiments were performed to verify the mRNA levels of the hub genes by quantitative real time polymerase chain reaction (qRT-PCR).

RESULTS

A total of 67 DEARGs and 2 hub DEARGs, HSPA8 and RPL15, were selected. The hub genes were closely related to the level of immune cell infiltration. GWAS analysis confirmed that the causative regions of the 2 hub genes in glaucoma were on chromosome 11 and chromosome 3, respectively. GSEA illustrated that pathways enriched for highly expressed HSPA8 and RPL15 contained immunity, autophagy, gene expression and energy metabolism-related pathways. qRT-PCR confirmed that the expression of Hspa8 and Rpl15 in the rat POAG model was consistent with the results of bioinformatics analysis.

CONCLUSIONS

This study indicated that HSPA8 and RPL15 may affect the progression of POAG by regulating autophagy and provided new ideas for the pathogenesis and treatment of POAG.

The role of dysregulated mRNA translation machinery in cancer pathogenesis and therapeutic value of ribosome-inactivating proteins

Dysregulated protein synthesis is a hallmark of tumors. mRNA translation reprogramming contributes to tumorigenesis, which is fueled by abnormalities in ribosome formation, tRNA abundance and modification, and translation factors. Not only malignant cells but also stromal cells within tumor microenvironment can undergo transformation toward tumorigenic phenotypes during translational reprogramming. Ribosome-inactivating proteins (RIPs) have garnered interests for their ability to selectively inhibit protein synthesis and suppress tumor growth. This review summarizes the role of dysregulated translation machinery in tumor development and explores the potential of RIPs in cancer treatment.

The Effects of Deregulated Ribosomal Biogenesis in Cancer

Ribosomes are macromolecular ribonucleoprotein complexes assembled from RNA and proteins. Functional ribosomes arise from the nucleolus, require ribosomal RNA processing and the coordinated assembly of ribosomal proteins (RPs), and are frequently hyperactivated to support the requirement for protein synthesis during the self-biosynthetic and metabolic activities of cancer cells. Studies have provided relevant information on targeted anticancer molecules involved in ribosome biogenesis (RiBi), as increased RiBi is characteristic of many types of cancer. The association between unlimited cell proliferation and alterations in specific steps of RiBi has been highlighted as a possible critical driver of tumorigenesis and metastasis. Thus, alterations in numerous regulators and actors involved in RiBi, particularly in cancer, significantly affect the rate and quality of protein synthesis and, ultimately, the transcriptome to generate the associated proteome. Alterations in RiBi in cancer cells activate nucleolar stress response-related pathways that play important roles in cancer-targeted interventions and immunotherapies. In this review, we focus on the association between alterations in RiBi and cancer. Emphasis is placed on RiBi deregulation and its secondary consequences, including changes in protein synthesis, loss of RPs, adaptive transcription and translation, nucleolar stress regulation, metabolic changes, and the impaired ribosome biogenesis checkpoint.

p21CIP/WAF1 saRNA inhibits proliferative vitreoretinopathy in a rabbit model

PURPOSE

Proliferative vitreoretinopathy (PVR) is a disease process resulting from proliferation of retinal pigment epithelial (RPE) cells in the vitreous and periretinal area, leading to periretinal membrane formation and traction and eventually to postoperative failure after vitreo-retinal surgery for primary rhegmatogenous retinal detachment (RRD). The present study was designed to test the therapeutic potential of a p21CIP/WAF1 (p21) inducing saRNA for PVR.

METHODS

A chemically modified p21 saRNA (RAG1-40-53) was tested in cultured human RPE cells for p21 induction and for the inhibition of cell proliferation, migration and cell cycle progression. RAG1-40-53 was further conjugated to a cholesterol moiety and tested for pharmacokinetics and pharmacodynamics in rabbit eyes and for therapeutic effects after intravitreal administration in a rabbit PVR model established by injecting human RPE cells.

RESULTS

RAG1-40-53 (0.3 mg, 1 mg) significantly induced p21 expression in RPE cells and inhibited cell proliferation, the progression of cell cycle at the G0/G1 phase and TGF-β1 induced migration. After a single intravitreal injection into rabbit eyes, cholesterol-conjugated RAG1-40-53 exhibited sustained concentration in the vitreal humor beyond at least 8 days and prevented the progression of established PVR.

CONCLUSION

p21 saRNA could represent a novel therapeutics for PVR by exerting a antiproliferation and antimigration effect on RPE cells.

Interaction of Camptothecin Anticancer Drugs with Ribosomal Proteins L15 and L11: A Molecular Docking Study

The antitumor drug topotecan (TPT) is a potent inhibitor of topoisomerase I, triggering DNA breaks lethal for proliferating cancer cells. The mechanism is common to camptothecins SN38 (the active metabolite of irinotecan) and belotecan (BLT). Recently, TPT was shown to bind the ribosomal protein L15, inducing an antitumor immune activation independent of topoisomerase I. We have modeled the interaction of four camptothecins with RPL15 derived from the 80S human ribosome. Two potential drug-binding sites were identified at Ile135 and Phe129. SN38 can form robust RPL15 complexes at both sites, whereas BLT essentially gave stable complexes with site Ile135. The empirical energy of interaction (ΔE) for SN38 binding to RPL15 is similar to that determined for TPT binding to the topoisomerase I-DNA complex. Molecular models with the ribosomal protein L11 sensitive to topoisomerase inhibitors show that SN38 can form a robust complex at a single site (Cys25), much more stable than those with TPT and BLT. The main camptothecin structural elements implicated in the ribosomal protein interaction are the lactone moiety, the aromatic system and the 10-hydroxyl group. The study provides guidance to the design of modulators of ribosomal proteins L11 and L15, both considered anticancer targets.

Spatially resolved transcriptomics revealed local invasion-related genes in colorectal cancer

Objective

Local invasion is the first step of metastasis, the main cause of colorectal cancer (CRC)-related death. Recent studies have revealed extensive intertumoral and intratumoral heterogeneity. Here, we focused on revealing local invasion-related genes in CRC.

Methods

We used spatial transcriptomic techniques to study the process of local invasion in four CRC tissues. First, we compared the pre-cancerous, cancer center, and invasive margin in one section (S115) and used pseudo-time analysis to reveal the differentiation trajectories from cancer center to invasive margin. Next, we performed immunohistochemical staining for RPL5, STC1, AKR1B1, CD47, and HLA-A on CRC samples. Moreover, we knocked down AKR1B1 in CRC cell lines and performed CCK-8, wound healing, and transwell assays to assess cell proliferation, migration, and invasion.

Results

We demonstrated that 13 genes were overexpressed in invasive clusters, among which the expression of CSTB and TM4SF1 was correlated with poor PFS in CRC patients. The ribosome pathway was increased, while the antigen processing and presentation pathway was decreased along CRC progression. RPL5 was upregulated, while HLA-A was downregulated along cancer invasion in CRC samples. Pseudo-time analysis revealed that STC1, AKR1B1, SIRPA, C4orf3, EDNRA, CES1, PRRX1, EMP1, PPIB, PLTP, SULF2, and EGFL6 were unpregulated along the trajectories. Immunohistochemic3al staining showed the expression of STC1, AKR1B1, and CD47 was increased along cancer invasion in CRC samples. Knockdown of AKR1B1 inhibited CRC cells' proliferation, migration, and invasion.

Conclusions

We revealed the spatial heterogeneity within CRC tissues and uncovered some novel genes that were associated with CRC invasion.