Molecular mechanism of the miR-7/BCL2L1/P53 signaling axis regulating the progression of hepatocellular carcinoma

Mitochondrial genome-derived circRNAs: Orphan epigenetic regulators in molecular biology

Mitochondria are vital for cellular activities, influencing ATP production, Ca2+ signaling, and reactive oxygen species generation. It has been proposed that nuclear genome-derived circular RNAs (circRNAs) play a role in biological processes. For the first time, this study aims to comprehensively explore experimentally confirmed human mitochondrial genome-derived circRNAs (mt-circRNAs) via in-silico analysis. We utilized wide-ranging bioinformatics tools to anticipate their roles in molecular biology, involving miRNA sponging, protein antagonism, and peptide translation. Among five well-characterized mt-circRNAs, SCAR/mc-COX2 stands out as particularly significant with the potential to sponge around 41 different miRNAs, which target several genes mostly involved in endocytosis, MAP kinase, and PI3K-Akt pathways. Interestingly, circMNTND5 and mecciND1 specifically interact with miRNAs through their unique back-splice junction sequence. These exclusively targeted miRNAs (has-miR-5186, 6888-5p, 8081, 924, 672-5p) are predominantly associated with insulin secretion, proteoglycans in cancer, and MAPK signaling pathways. Moreover, all mt-circRNAs intricately affect the P53 pathway through miRNA sequestration. Remarkably, mc-COX2 and circMNTND5 appear to be involved in the RNA's biogenesis by antagonizing AGO1/2, EIF4A3, and DGCR8. All mt-circRNAs engaged with IGF2BP proteins crucial in redox signaling, and except mecciND1, they all potentially generate at least one protein resembling the immunoglobulin heavy chain protein. Given P53's function as a redox-sensitive transcription factor, and insulin's role as a crucial regulator of energy metabolism, their indirect interplay with mt-circRNAs could influence cellular outcomes. However, due to limited attention and infrequent data availability, it is advisable to conduct more thorough investigations to gain a deeper understanding of the functions of mt-circRNA.

Investigating the molecular mechanism of Qizhu anticancer prescription in inhibiting hepatocellular carcinoma based on high-resolution mass spectrometry and network pharmacology

ETHNOPHARMACOLOGICAL RELEVANCE

Of all primary liver cancer cases, hepatocellular carcinoma (HCC) accounts for about 90%. Most patients with HCC receive a diagnosis in the medium-to-late stages or with chronic liver disease, have lost the opportunity for radical treatment, such as surgical resection, and their 5-year survival rate is low. Qizhu Anticancer Prescription (QZACP) is an empirical formula composed of traditional Chinese herbs that can clinically relieve HCC symptoms, inhibit the progression of HCC, reduce recurrence rate, and prolong survival; however, its exact mode of action remains unknown.

AIM OF THE STUDY

This study's purpose was to investigate the mode of action of QZACP in the prevention and treatment of HCC.

MATERIALS AND METHODS

Initially, drug components in the QZACP decoction were analyzed using high-resolution mass spectrometry. A subcutaneous tumor xenograft model in nude mice was constructed to further analyze the active components of QZACP that had entered tumor tissues through oral administration. Potential targets of QZACP in the prevention and treatment of HCC were identified and then confirmed in vivo via network pharmacology and molecular docking. In addition, regulatory effects of QZACP on HCC cell proliferation and the cell cycle were detected using a CCK-8 assay and flow cytometry.

RESULTS

High-resolution mass spectrometry revealed that the QZACP decoction contained deacetyl asperulosidic acid methyl ester (DAAME), paeoniflorin, calycosin-7-glucoside, liquiritin, glycyrrhizic acid, astragaloside IV, saikosaponin A, curdione, and atractylenolide II. In nude mice, QZACP could effectively inhibit the growth of subcutaneous tumors, where DAAME, paeoniflorin, liquiritin, and glycyrrhizic acid could enter liver cancer tissues after oral administration. Among these, DAAME was the most highly expressed in HCC tissues and may be an important active component of QZACP for inhibiting HCC. Utilizing network pharmacology, the targets of action of these four drug components were identified. After verification using western blotting, STAT3, VEGFA, JUN, FGF2, BCL2L1, AR, TERT, MMP7, MMP1, ABCB1, CA9, and ESR2 were identified as targets of QZACP inhibition in HCC. In vitro experiments revealed that QZACP inhibited the proliferation of HCC cells while inducing G0/G1 phase cell cycle arrest. In vivo experiments demonstrated that DAAME significantly inhibited HCC growth. After intersection of the 24 DAAME targets predicted using network pharmacology with the 435 HCC disease targets, only CA9 was identified as a DAAME-HCC crossover target. Molecular docking results revealed that the binding site of DAAME and CA9 had good stereo-complementarity with a docking score of -8.1 kcal/mol. Western blotting and immunohistochemical results also confirmed that DAAME significantly decreased CA9 protein expression in HCC.

CONCLUSIONS

QZACP inhibits HCC by reducing the expression of STAT3, VEGFA, JUN, FGF2, BCL2L1, AR, TERT, MMP7, MMP1, ABCB1, CA9, and ESR2. DAAME may be an important active component of QZACP for the prevention and treatment of HCC, inhibiting it by targeting the expression of CA9.

Gene expression signatures of stepwise progression of Hepatocellular Carcinoma

The molecular pathogenesis of Hepatocellular Carcinoma (HCC) is a complex process progressing from premalignant stages to cancer in a stepwise manner. Mostly, HCC is detected at advanced stages, leading to high mortality rates. Hence, characterising the molecular underpinnings of HCC from normal to cancer state through precancerous state may help in early detection and improve its prognosis and treatment. In this work, we analysed the transcriptomic profile of tumour and premalignant samples from HCC or chronic liver disease patients, who had undergone either total or partial hepatectomy. The normal samples from patients with metastatic cancer/polycystic liver disease/ cholangiocarcinoma were also included. A gene co-expression network approach was applied to identify hierarchical changes: modules, pathways, and genes related to different trajectories of HCC and patient survival. Our analysis shows that the progression from premalignant conditions to tumour is accompanied by differences in the downregulation of genes associated with HNF4A activity and the immune system and upregulation of cell cycle genes, bringing about variability in patient outcomes. However, an increase in immune and cell cycle activity is observed in premalignant samples. Interestingly, co-expression modules and genes from premalignant stages are associated with survival. THBD, a classical marker for dendritic cells, is a predictor of survival at the premalignant stage. Further, genes linked to microtubules, kinetochores, and centromere are altered in both premalignant and tumour conditions and are associated with survival. Our analysis revealed a three-way molecular axis of liver function, immune pathways, and cell cycle driving HCC pathogenesis.

The pivotal role of EMT-related noncoding RNAs regulatory axes in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) remains a major health problem worldwide, being the leading cause of cancer-related deaths, with limited treatment options, especially in its advanced stages. Tumor resistance is closely associated with the activation of the EMT phenomenon and its reversal, being modulated by different molecules, including noncoding RNAs (ncRNAs). Noncoding RNAs have the potential to function as both tumor suppressors and oncogenic molecules, controlling the malignant potential of HCC cells. Basically, these molecules circulate in the tumor microenvironment, encapsulated in exosomes. Their impact on cell biology is more significant than originally expected, which makes related research rather complex. The temporal and spatial expression patterns, precise roles and mechanisms of specific ncRNAs encapsulated in exosomes remain primarily unknown in different stages of the disease. This review aims to highlight the recent advances in ncRNAs related to EMT and classifies the described mechanism as direct and indirect, for a better summarization. Moreover, we provide an overview of current research on the role of ncRNAs in several drug resistance-related pathways, including the emergence of resistance to sorafenib, doxorubicin, cisplatin and paclitaxel therapy. Nevertheless, we comprehensively discuss the underlying regulatory mechanisms of exosomal ncRNAs in EMT-HCC via intercellular communication pathways.