PAQR4 promotes the development of hepatocellular carcinoma by activating PI3K/AKT pathway

A novel transcriptomic signature associated with lymphovascular invasion predicts clinical outcomes, tumor microenvironment, and therapeutic response in lung adenocarcinoma

PURPOSE

Since TNM staging has limitations for predicting post-operative outcomes and relapse, more effective prediction tools need to be researched and developed. Lymphovascular invasion, LVI, as a histopathological feature, has been widely shown to have a correlation with poor prognosis and early recurrence of lung adenocarcinoma (LUAD). However, LVI assessment is limited by subjective bias, and therefore its efficacy in practical clinical application needs further clarification. The aim of this study was to formulate a new signature based on LVI-related genes to predict prognosis and recurrence in patients with lung adenocarcinoma.

METHODS

Clinicopathological information, gene sequencing data and whole slide images (WSIs) of LUAD patients were downloaded from the Cancer Genome Atlas (TCGA) databases. LVI statue were evaluated by professional pathologists, and then the differentially expressed genes (LVI DEGs) associated with LVI were screened. The least absolute shrinkage and selection operator (LASSO) and Step Cox regression models were used to construct LVI-associated risk scores (LVRS), including PAQR4, ARGHEF6, CKS1B, CFTR and SEC14L4. The validity of the LVRS score was evaluated on multiple external datasets and our JSSZL cohort dataset. Using LVRS scores and clinical information, nomogram were constructed for use by clinicians. In addition, we further explored the relationship between LVRS score and clinicopathological features, immune infiltration, tumor mutational load, and immunotherapy response, and confirmed the expression of key genes in LVRS score in lung adenocarcinoma tissues using qRT-PCR and immunohistochemistry (IHC) techniques.

RESULTS

Based on the LVRS, patients could be classified into high-LVRS and low-LVRS groups. It was found that OS and PFS were significantly worse in the high-LVRS group than in the low-LVRS group (p < 0.001). By ROC curve analysis, it could be found that the nomogram combining LVRS and clinical information could accurately predict the prognosis of LUAD patients with the area under the curve of 1,3,5-year survival rate could reach 0.754, 0.741 and 0.735. The results of univariate and multivariate analysis showed that LVRS was an independent prognostic factor. At the same time, there were significant differences in the mutation profiles and immune microenvironment between the high-LVRS and low-LVRS groups, with the high-LVRS group having a significantly higher mutation rate than the low-LVRS group and exhibiting immunological "cold" features. By the experimental results, higher expression levels of PAQR4 and CKS1B were found in LUAD tissues, while lower expression levels of ARGHEF6, CFTR and SEC14L4 were observed.

CONCLUSIONS

The LVRS established in this study serves as a valid tool to predict the prognosis and recurrence status of lung adenocarcinoma patients and has a predictive effect on the response to postoperative treatment. The establishment of LVRS may offer some theoretical support to clinical treatment strategies for patients with lung adenocarcinoma following surgical intervention.

Integrative pan-cancer analysis reveals the importance of PAQR family in lung cancer

BACKGROUND

The progestin and adipoQ receptors (PAQRs) family contains 11 genes involved in the regulation of metabolism and cancer development. However, a comprehensive understanding of the role of PAQRs in cancer remains largely scarce, and the associations between their expression levels and immune signatures also need to be researched.

METHODS

Here, we applied pan-cancer analysis to explore the associations between PAQRs expression and survival, tumor microenvironment (TME), and drug sensitivity from the UCSC Xena and CellMiner databases. Besides, we further studied the expression, survival and somatic mutations of PAQRs in lung cancer (LC) from TCGA database.

RESULTS

The results showed that PAQRs had significant heterogeneity with some upregulation and some downregulation in most tumors. Specifically, compared with PAQR3/5/6/9 and MMD2, ADIPOR1/2, PAQR4/7/8 and MMD had higher levels of average expression in all tumor types. PAQRs expression was greatly correlated with survival, immune subtypes, TME, and drug sensitivity. Furthermore, this research concentrated on analyzing the relationship of PAQRs expression with LC prognosis, and proved that ADIPOR2, PAQR4/9 and MMD were independent prognostic factors for LC patients. Finally, based on somatic mutation data, the genetic mutations in LC patients were majorly missense mutations, and TP53 and TTN had the top two highest mutation frequencies.

CONCLUSION

Collectively, PAQRs may serve as robust biomarkers to predict the prognosis and guide immunotherapy of tumors, especially LC, which enables novel ways for improving cancer treatment.

Small RNA sequencing and identification of Andrographis paniculata miRNAs with potential cross‑kingdom human gene targets

Cross-species post-transcriptional regulatory potential of plant derived small non-coding microRNAs (miRNAs) has been well documented by plenteous studies. MicroRNAs are transferred to host cells via oral ingestion wherein they play a decisive role in regulation of host genes; thus, miRNAs have evolved as the nascent bioactive molecules imparting pharmacological values to traditionally used medicinal plants. The present study aims to investigate small RNA profiling in order to uncover the potential regulatory role of miRNAs derived from Andrographis paniculata, one of the most widely used herb by tribal communities for liver disorders and document the pharmacological properties of A. paniculata miRNAs. In this study, high-throughput sequencing method was used to generate raw data, ~ 60 million sequences were generated from A. paniculata leaves. Using computational tools and bioinformatics approach, analyses of 3,480,097 clean reads resulted in identification of 3440 known and 51 putative novel miRNAs regulating 1365 and 192 human genes respectively. Remarkably, the identified plausible novel miRNAs apa-miR-5, apa-miR-1, apa-miR-26, and apa-miR-30 are projected to target significant host genes including CDK6, IKBKB, TRAF3, CHD4, MECP2, and ADIPOQ. Subsequent annotations revealed probable involvement of the target genes in various pathways for instance p38-MAPK, AKT, AMPK, NF-Kβ, ERK, WNT signalling, MYD88 dependant cascade, and pathways in cancer. Various diseases such as human papilloma virus infection, Alzheimer's, Non-alcoholic Fatty Liver, Alcoholic liver diseases, HepatoCellular Carcinoma (HCC), and numerous other cancers were predominantly found to be linked with target genes. Our findings postulate novel interpretations regarding modulation of human transcripts by A. paniculata miRNAs and exhibit the regulation of human diseases by plant-derived miRNAs. Though our study elucidates miRNAs as novel therapeutic agents, however, experimental validations for assessment of therapeutic potential of these miRNAs are still warranted.

VEZF1, destabilized by STUB1, affects cellular growth and metastasis of hepatocellular carcinoma by transcriptionally regulating PAQR4

Hepatocellular carcinoma (HCC) is an aggressive solid malignancy, and recurrence and metastasis are major incentives contributing to its poor outcome. Vascular endothelial zinc finger 1 (VEZF1) has been recognized as an oncoprotein in certain types of cancer, but the expression pattern and regulatory mechanism in HCC remains unclear. This study focused on the functional effect and regulatory basis of VEZF1 in HCC. Microarray analysis identified the differentially expressed VEZF1 in HCC, and we validated its raised expression in HCC clinical samples. Artificial modulation of VEZF1 (knockdown and overexpression) was conducted to explore its role in HCC progression both in vitro and in vivo. It was shown that silencing of VEZF1 suppressed, whereas its overexpression promoted HCC cellular proliferation and metastasis abilities. Mechanistically, VEZF1 transcriptionally activated progestin and adipoQ receptor 4 (PAQR4) to accelerate HCC progression. Furthermore, VEZF1 is confirmed as a substrate of stress-inducible phosphoprotein 1 homology and U-box containing protein 1 (STUB1), and its stability is impacted by STUB1-mediated ubiquitination degradation. Conjointly, our work suggested that VEZF1, destabilized by STUB1, participates in HCC progression by regulating PAQR4. The STUB1/VEZF1/PAQR4 mechanism might provide novel insights on guiding early diagnosis and therapy in HCC patients.

ALKBH5 prevents hepatocellular carcinoma progression by post-transcriptional inhibition of PAQR4 in an m6A dependent manner

BACKGROUND

N6-methyladenosine (m6A) is a prevalent modification of mRNA and is known to play important roles in tumorigenesis in many types of cancer. The function of N6-methyladenosine (m6A) RNA methylation depends on a variety of methyltransferases and demethylases. AlkB homolog 5 (ALKBH5) is a demethylase, and its biological function has not been completely explored in HCC.

RESULTS

ALKBH5 is downregulated and has antitumor effects in HCC cells. In addition, Progestin and AdipoQ Receptor 4 (PAQR4) was identified as a downstream target of ALKBH5 based on transcriptome sequencing and validation studies. We found that ALKBH5 decreases PAQR4 mRNA and protein expression in an N6-methyladenosine (m6A)-dependent manner. The study also showed that ALKBH5 changes PAQR4 expression via the m6A reader IGF2BP1. In both in vivo and in vitro experiments, PAQR4 showed a strong association with the development of HCC. Finally, we found that PAQR4 interacts with AKT and enhances PI3K/AKT pathway activation.

CONCLUSIONS

ALKBH5 inhibits HCC growth by downregulating PAQR4 expression in an m6A-dependent manner, therefore suppressing PI3K/AKT pathway activation.

Long non-coding RNAs (lncRNAs) in hepatocellular carcinoma progression: Biological functions and new therapeutic targets

Liver is an important organ in body that performs vital functions such as detoxification. Liver is susceptible to development of cancers, and hepatocellular carcinoma (HCC) is among them. 75-85% of liver cancer cases are related to HCC. Therefore, much attention has been directed towards understanding factors mediating HCC progression. LncRNAs are epigenetic factors with more than 200 nucleotides in length located in both nucleus and cytoplasm and they are promising candidates in cancer therapy. Directing studies towards understanding function of lncRNAs in HCC is of importance. LncRNAs regulate cell cycle progression and growth of HCC cells, and they can also induce/inhibit apoptosis in tumor cells. LncRNAs affect invasion and metastasis in HCC mainly by epithelial-mesenchymal transition (EMT) mechanism. Revealing the association between lncRNAs and downstream signaling pathways in HCC is discussed in the current manuscript. Infectious diseases can affect lncRNA expression in mediating HCC development and then, altered expression level of lncRNA is associated with drug resistance and radio-resistance. Biomarker application of lncRNAs and their role in prognosis and diagnosis of HCC are also discussed to pave the way for treatment of HCC patients.

Pancancer Analysis of the Prognostic and Immunotherapeutic Value of Progestin and AdipoQ Receptor 4

AdipoQ receptor 4 (PAQR4) belongs to the family of progestin and AdipoQ receptors. PAQR4 plays an oncogenic role in lung and breast cancer. However, systematic pancancer analyses of PAQR4 have not been performed. The purpose was to investigate the prognostic and immunological significance of PAQR4 across 31 tumor types. Data were obtained from the following sources: TCGA, GEO, UALCAN, TIMER, GEPIA2, KM plotter, and TISIDB databases. The results proved that PAQR4 expression was significantly elevatory in most cancer types. We then explored the utility of PAQR4 as a prognostic indicator across all cancers. Using Cox proportional risk regression models, it has been demonstrated that PAQR4 is an independent risk factor in. High PAQR4 expression was not associated with other prognostic indicators, including overall survival, disease-free interval, disease-specific survival, and progression-free period. Subsequently, we explored the immunological value of PAQR4 and found that PAQR4 expression significantly correlated with tumor mutational burden, microsatellite instability, neoantigen, and immune checkpoint genes in tumors. It also significantly negatively correlated with most tumors' ESTIMATE scores, indicating that PAQR4 can influence the cellular composition of the tumor microenvironment. Our findings suggest the immunotherapeutic potential of PAQR4 in tumors. Finally, we explored the role of PAQR4 in tumor drug resistance and found that PAQR4 expression affected the sensitivity to multiple chemotherapeutic agents. A significant role for PAQR4 in tumor immunity is evident in these studies, as well as its potential role in cancer diagnosis, prognosis, and treatment precision.

Pan-cancer analysis of the prognostic and immunological role of PAQR4

Progestin and adipoQ receptor family member 4 (PAQR4) is a protein-coding gene. Recent studies have shown that PAQR4 is related to the development of multiple cancers. However, there is no systematic pan-cancer analysis of this gene. In this study, the expression of PAQR4, correlations with clinical prognosis, immune situation, and its potential molecular functions and mechanisms in pan-cancer were explored by bioinformatics analysis. The Cancer Genome Atlas was applied to investigate the relations between PAQR4 and clinical features, prognostic effects, and tumor immune microenvironment. R software was used to perform statistical analysis and figure creation. The expression of PAQR4 in BLCA and KIRC was validated by qRT-PCR and immunohistochemistry, and its function was explored by cellular experiments. Bioinformatics analysis revealed that PAQR4 was up-regulated in multiple cancers and related to poor prognosis. The high expression of PAQR4 was closely associated with high tumor stage, immune cell infiltration, tumor mutation burden, and microsatellite instability in different cancer types. In addition, the high expression of PAQR4 also indicated involvement in the immune regulatory pathways. The involvement of PAQR4 in the immune regulation of different tumors was confirmed by GSEA enrichment analysis. Moreover, PAQR4 was highly expressed in bladder cancer and renal clear cell carcinoma tissues and cell lines. Cell proliferation, migration, and invasion of bladder cancer and renal clear cell carcinoma cell lines were significantly decreased after the knockdown of PAQR4. This study elucidated the role of PAQR4 in carcinogenesis as well as tumor immunity. PAQR4 may serve as a potential prognostic biomarker in a variety of cancers.

KDM5B regulates the PTEN/PI3K/Akt pathway to increase sorafenib-resistance in hepatocellular carcinoma

Lysine-specific demethylase 5B (KDM5B) exerts its tumor-promoting functions in numerous malignancies, although the possible mechanisms by which KDM5B promotes cancer aggressiveness in hepatocellular carcinoma (HCC) have been preliminarily explored, the role of this gene in regulating sorafenib-resistance in HCC has not been studied. Thus, the present study was designed to resolve this problem, and our data suggested that KDM5B was significantly upregulated in the HCC tissues collected from patients with sorafenib treatment history. Consistently, continuous low-dose sorafenib administration increased KDM5B expression levels in the sorafenib-resistant HCC cells compared to their sorafenib-sensitive counterparts. Next, by performing the functional experiments, we found that KDM5B positively regulated sorafenib-resistance and cancer stem cell (CSC) properties in HCC cells in vitro and in vivo. Furthermore, upregulation of KDM5B-degraded phosphatase and tensin homolog (PTEN), results in the activation of the downstream oncogenic PI3K/Akt pathway. Subsequently, the rescuing experiments verified that the promoting effects of KDM5B overexpression on chemoresistance and cancer stemness in HCC cells were all abrogated by PI3K (p110) knockdown and PTEN overexpression. Collectively, those data hinted that KDM5B influenced CSC properties and sorafenib-resistance in HCC cells through modulating the PTEN/PI3K/Akt pathway, and KDM5B could be used as a potential target for the treatment of HCC in clinic.

Sortilin 1 regulates hepatocellular carcinoma progression by activating the PI3K/AKT signaling

Background

Sortilin 1 (SORT1) has been reported as an oncogene in several human tumors. Nonetheless, the biological functions of SORT1 in hepatocellular carcinoma (HCC) remain poorly understood.

Methods

Western blotting was employed for the determination of protein expression. Hepatocellular carcinoma cell viability, apoptosis, migration, and invasion were measured via CCK-8, flow cytometry, wound healing, and Transwell assays.

Results

Sortilin 1 was upregulated in HCC and closely associated with unsatisfactory outcomes of HCC patients. Furthermore, in vitro and in vivo assays revealed that SORT1 knockdown significantly diminished HCC cell proliferation and metastasis but accelerated HCC cell apoptosis; moreover, SORT1 depletion also restrained the growth of xenografted HCC tumors. Mechanistically, SORT1 activated PI3K/AKT signaling in HCC cells, thereby promoting the malignant behaviors of HCC cells.

Conclusion

This study demonstrated that SORT1 might promote HCC progression by activating PI3K/AKT signaling, indicating that SORT1 might be a promising target and biomarker for HCC treatment and prognosis.