The role of exosomes in cancer-related programmed cell death

The important role of cuproptosis and cuproptosis-related genes in the development of thyroid carcinoma revealed by transcriptomic analysis and experiments

OBJECTIVE

Programmed Cell Death (PCD) processes have been suggested to play a role in the development of cancers. The study aimed to investigate the enrichment of different types of PCD and identify important PCD-related genes in Thyroid Carcinoma (THCA).

METHODS

The whole study is based on transcriptomic analysis and Immunohistochemistry (IHC) experiments. For transcriptomic analysis, the transcriptomic data of THCA (n = 493) and normal thyroid samples (n = 58) was used. The enrichment score of different types of PCD in THCA samples was calculated and the most enriched PCD process was identified. Then the expression of PCD-related genes in control and THCA samples were compared and the association between cuproptosis and characteristics of Tumor Microenvironment (TME) in THCA tissues was explored. IHC experiment was performed to confirm gene expressions in THCA and para-tumor samples.

RESULTS

Enrichment analysis showed that cuproptosis was the most enriched type of PCD process and associated with malignancy in THCA. The expression of a cuproptosis-related gene, CDKN2A, was found and confirmed to be higher in THCA than normal samples and associated with poor outcomes and higher clinical stages of patients with THCA. Moreover, CDKN2A expression was associated with immunosuppressive TME in THCA.

CONCLUSION

Our findings indicated the important role of cuproptosis and a cuproptosis-related gene, CDKN2A, in the development and progression of THCA, which might provide novel insights into the understanding of pathophysiology of THCA.

In silico identification of multidrug resistance gene (MDR)-targeted transposon miRNAs in human cancer

miRNAs are small RNA molecules that regulate gene expression and play important roles in various biological processes in cells. The discovery of miRNAs is also of great importance in cancer research. miRNAs enable the development of new approaches in cancer treatment by regulating gene expression in cancer cells and have an important place in cancer development, treatment, and diagnosis. Multidrug resistance (MDR) in cancer is associated with the overexpression of ATP-binding cassette (ABC) transporter proteins in cancer cells. MDR contributes to the dysregulation of ABC transporter proteins, and miRNAs mediate MDR in various cancers, resulting in drug resistance. In this study, it was aimed to identify new miRNA sequences in genes associated with multidrug resistance in cancer using in silico method. After obtaining the mature human miRNA sequences in the miRBASE database, BLAST analyses were performed with these sequences for five multidrug resistance genes (ABCB1, ABCC3, ABCC10, ABCC11, ABCG2) known to be associated with cancer. The RNAhybrid tool was used to find the minimum free energy hybridization of gene and miRNA. The target genes of pre-miRNAs and the metabolic pathways in which the target genes play a role were identified with GeneMANIA, SRplot, miRTargetLink programs. Phylogenetic trees of miRNAs belonging to genes were created using the MEGA X software. Secondary structures of pre-miRNA sequences were determined using the RNAfold Web Server program. According to the data obtained from the study, 107 miRNAs associated with multidrug resistance were identified in human cancers. Transmembrane transporter, drug transport and response to drug functions, and metabolic activities of miRNA-related pathways of MDR genes in various cancer types were determined. Multidrug resistance (MDR) in cancer is often associated with overexpression of ABC transporter proteins, which can lead to failure of cancer treatments. Additionally, the relationship of miRNAs with ABC transporter proteins constitutes an important research area to understand the mechanisms of drug resistance and develop new treatment strategies.

Picrasidine I Regulates Apoptosis in Melanoma Cell Lines by Activating ERK and JNK Pathways and Suppressing AKT Signaling

World Health Organization data indicate a continuous increase in melanoma incidence, with metastatic melanoma characterized by poor prognosis and drug resistance. The exploration of therapeutics derived from natural products remains an active area of in vitro research. The aim of this study was to determine the antitumor effects of picrasidine I, a natural compound extracted from Picrasma quassioides, against two melanoma cell lines. We selected two metastatic melanoma cell lines, HMY-1 and A2058, for molecular studies, including Western blotting, 4',6-diamidino-2-phenylindole staining, and flow cytometry. Picrasidine I demonstrated cytotoxic effects against the HMY-1 and A2058 melanoma cell lines. It induced cell cycle arrest in the sub-G1 phase and downregulated cell cycle-related proteins (e.g., cyclin A2, D1, cyclin-dependent kinases 4, and 6). In the intrinsic apoptosis pathway, picrasidine I activated proapoptotic proteins (e.g., Bax, Bak, t-Bid, BimL/S) and suppressed the expression of antiapoptotic proteins (e.g., Bcl-2, Bcl-xL), with an observed increase in the quantity of depolarized cells. In addition, the apoptotic effects of picrasidine I were linked to the activation of the c-Jun N-terminal kinase and extracellular signal-regulated kinase pathways and the inhibition of the protein kinase B signaling pathway. A human apoptosis array indicated claspin inhibition upon picrasidine I treatment, suggesting the potential involvement of picrasidine I in apoptosis and cell cycle regulation. Our findings suggest that picrasidine I has potential as a candidate for treating advanced melanoma, and thus these findings warrant further investigation. The modulation of claspin expression by picrasidine I could be investigated further as a potential biomarker to predict its efficacy in related to advanced stages of melanoma.

Discovering the role of microRNAs and exosomal microRNAs in chest and pulmonary diseases: a spotlight on chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease (COPD) is a progressive respiratory condition and ranks as the fourth leading cause of mortality worldwide. Despite extensive research efforts, a reliable diagnostic or prognostic tool for COPD remains elusive. The identification of novel biomarkers may facilitate improved therapeutic strategies for patients suffering from this debilitating disease. MicroRNAs (miRNAs), which are small non-coding RNA molecules, have emerged as promising candidates for the prediction and diagnosis of COPD. Studies have demonstrated that dysregulation of miRNAs influences critical cellular and molecular pathways, including Notch, Wnt, hypoxia-inducible factor-1α, transforming growth factor, Kras, and Smad, which may contribute to the pathogenesis of COPD. Extracellular vesicles, particularly exosomes, merit further investigation due to their capacity to transport various biomolecules such as mRNAs, miRNAs, and proteins between cells. This intercellular communication can significantly impact the progression and severity of COPD by modulating signaling pathways in recipient cells. A deeper exploration of circulating miRNAs and the content of extracellular vesicles may lead to the discovery of novel diagnostic and prognostic biomarkers, ultimately enhancing the management of COPD. The current review focus on the pathogenic role of miRNAs and their exosomal counterparts in chest and respiratory diseases, centering COPD.

Targeting NQO1 induces ferroptosis and triggers anti-tumor immunity in immunotherapy-resistant KEAP1-deficient cancers

Immunotherapy has revolutionized cancer treatment, yet the efficacy of immunotherapeutic approaches remains limited. Resistance to ferroptosis is one of the reasons for the poor therapeutic outcomes in tumors with Kelch-like ECH-associated protein 1 (KEAP1) mutations. However, the specific mechanisms by which KEAP1-mutant tumors resist immunotherapy are not fully understood. In this study, we showed that the loss of function in KEAP1 results in resistance to ferroptosis. We identified NAD(P)H Quinone Dehydrogenase 1 (NQO1) as a transcriptional target of nuclear factor erythroid 2-related factor 2 (NRF2) and revealed that inducing NQO1-mediated ferroptosis in KEAP1-deficient tumors triggers an antitumor immune cascade. Additionally, it was found that NQO1 protein levels could serve as a candidate biomarker for predicting sensitivity to immunotherapy in clinical tumor patients. We validated these findings in several preclinical tumor models. Overall, KEAP1 mutations define a unique disease phenotype, and targeting its key downstream molecule NQO1 offers new hope for patients with resistance to immunotherapy.

Research progress in in vivo tracing technology for extracellular vesicles

Cells have the capability to discharge extracellular vesicles (EVs) into a range of bodily fluids. Extracellular vesicles (EVs) encapsulate biological molecules such as proteins and nucleic acids, playing a role in facilitating cell-cell communication. They actively engage in a myriad of physiological and pathological processes. In vivo tracing of EVs in organisms significantly contributes to elucidating the biological mechanisms of EV-based therapy. The development of molecular imaging technology makes it possible to trace EVs in vivo. Experiments frequently employ a range of molecular imaging techniques, encompassing bioluminescence imaging, fluorescence imaging, magnetic resonance imaging, single photon emission computed tomography, positron emission tomography, photoacoustic imaging, and multimodal imaging. These methods have their own advantages and disadvantages. In this review, typical applications of in vivo tracing of EVs are reviewed.