Hypoxia-driven tumor stromal remodeling and immunosuppressive microenvironment in scirrhous HCC

The crosstalk between cellular survival pressures and N6-methyladenosine modification in hepatocellular carcinoma

BACKGROUND

Within the tumor microenvironment, survival pressures are prevalent with potent drivers of tumor progression, angiogenesis, and therapeutic resistance. N6-methyladenosine (m6A) methylation has been recognized as a critical post-transcriptional mechanism regulating various aspects of mRNA metabolism. Understanding the intricate interplay between survival pressures and m6A modification provides new insights into the molecular mechanisms underlying hepatocellular carcinoma (HCC) progression and highlights the potential for targeting the survival pressures-m6A axis in HCC diagnosis and treatment.

DATA SOURCES

A literature search was conducted in PubMed, MEDLINE, and Web of Science for relevant articles published up to April 2024. The keywords used for the search included hepatocellular carcinoma, cellular survival, survival pressure, N6-methyladenosine, tumor microenvironment, stress response, and hypoxia.

RESULTS

This review delves into the multifaceted roles of survival pressures and m6A RNA methylation in HCC, highlighting how survival pressures modulate the m6A landscape, the impact of m6A modification on survival pressure-responsive gene expression, and the consequent effects on HCC cell survival, proliferation, metastasis, and resistance to treatment. Furthermore, we explored the therapeutic potential of targeting this crosstalk, proposing strategies that leverage the understanding of survival pressures and m6A RNA methylation mechanisms to develop novel, and more effective treatments for HCC.

CONCLUSIONS

The interplay between survival pressures and m6A RNA methylation emerges as a complex regulatory network that influences HCC pathogenesis and progression.

The resistance to anoikis, mediated by Spp1, and the evasion of immune surveillance facilitate the invasion and metastasis of hepatocellular carcinoma

Anoikis-Related Genes (ARGs) lead to the organism manifesting resistance to anoikis and are associated with unfavorable prognostic outcomes across various malignancies.Therefore, it is crucial to identify the pivotal target genes related to anoikis in HCC .We found that ARGs were significantly correlated with prognosis and immune responses in HCC. The core gene, SPP1, notably promoted anoikis resistance and metastasis in HCC through both in vivo and in vitro studies. The PI3K-Akt-mTOR pathway played a critical role in anoikis suppression within HCC contexts. Our research unveiled SPP1's role in enhancing PKCα phosphorylation, which in turn activated the PI3K-Akt-mTOR cascade. Additionally, SPP1 was identified as a key regulator of MDSCs and Tregs migration, directly affecting their immunosuppressive capabilities.These findings indicate that in HCC, SPP1 promoted anoikis resistance and facilitated immune evasion by modulating MDSCs and Tregs.

Applications of single-cell multi-omics in liver cancer

Primary liver cancer, more specifically hepatocellular carcinoma (HCC), remains a significant global health problem associated with increasing incidence and mortality. Clinical, biological, and molecular heterogeneity are well-known hallmarks of cancer and HCC is considered one of the most heterogeneous tumour types, displaying substantial inter-patient, intertumoural and intratumoural variability. This heterogeneity plays a pivotal role in hepatocarcinogenesis, metastasis, relapse and drug response or resistance. Unimodal single-cell sequencing techniques have already revolutionised our understanding of the different layers of molecular hierarchy in the tumour microenvironment of HCC. By highlighting the cellular heterogeneity and the intricate interactions among cancer, immune and stromal cells before and during treatment, these techniques have contributed to a deeper comprehension of tumour clonality, hematogenous spreading and the mechanisms of action of immune checkpoint inhibitors. However, major questions remain to be elucidated, with the identification of biomarkers predicting response or resistance to immunotherapy-based regimens representing an important unmet clinical need. Although the application of single-cell multi-omics in liver cancer research has been limited thus far, a revolution of individualised care for patients with HCC will only be possible by integrating various unimodal methods into multi-omics methodologies at the single-cell resolution. In this review, we will highlight the different established single-cell sequencing techniques and explore their biological and clinical impact on liver cancer research, while casting a glance at the future role of multi-omics in this dynamic and rapidly evolving field.

Investigating autophagy and intricate cellular mechanisms in hepatocellular carcinoma: Emphasis on cell death mechanism crosstalk

Hepatocellular carcinoma (HCC) stands as a formidable global health challenge due to its prevalence, marked by high mortality and morbidity rates. This cancer type exhibits a multifaceted etiology, prominently linked to viral infections, non-alcoholic fatty liver disease, and genomic mutations. The inherent heterogeneity of HCC, coupled with its proclivity for developing drug resistance, presents formidable obstacles to effective therapeutic interventions. Autophagy, a fundamental catabolic process, plays a pivotal role in maintaining cellular homeostasis, responding to stressors such as nutrient deprivation. In the context of HCC, tumor cells exploit autophagy, either augmenting or impeding its activity, thereby influencing tumorigenesis. This comprehensive review underscores the dualistic role of autophagy in HCC, acting as both a pro-survival and pro-death mechanism, impacting the trajectory of tumorigenesis. The anti-carcinogenic potential of autophagy is evident in its ability to enhance apoptosis and ferroptosis in HCC cells. Pertinently, dysregulated autophagy fosters drug resistance in the carcinogenic context. Both genomic and epigenetic factors can regulate autophagy in HCC progression. Recognizing the paramount importance of autophagy in HCC progression, this review introduces pharmacological compounds capable of modulating autophagy-either inducing or inhibiting it, as promising avenues in HCC therapy.