Nanotechnology-Based Weapons to Combat Human Papillomavirus Infection Associated Diseases

A replicative recombinant HPV16 E7 expression virus upregulates CD36 in C33A cells

Objective

In past decades, the role of high-risk HPV (HR-HPV) infection in cancer pathogenesis has been extensively studied. The viral E7 protein expressed in pre-malignant cells has been identified as an ideal target for immunological intervention. However, the cultivation of HPV in vitro remains a significant challenge, as well as the lack of methods for expressing the HPV E7 protein and generating replication-competent recombinant viral particles, which posed a major obstacle to further exploration of the function and carcinogenic mechanisms of the E7 oncoprotein. Therefore, it is imperative to investigate novel methodologies to construct replication-competent recombinant viral particles that express the HPV E7 protein to facilitate the study of its function.

Methods

We initiated the construction of recombinant viral particles by utilizing the ccdB-Kan forward/reverse screening system in conjunction with the Red/ExoCET recombinant system. We followed the infection of C33A cells with the obtained recombinant virus to enable the continuous expression of HPV16 E7. Afterwards, the total RNA was extracted and performed transcriptome sequencing using RNA-Seq technology to identify differentially expressed genes associated with HPV-induced oncogenicity.

Results

We successfully established replicative recombinant viral particles expressing HPV16 E7 stably and continuously. The C33A cells were infected with recombinant viral particles to achieve overexpression of the E7 protein. Subsequently, RNA-Seq analysis was conducted to assess the changes in host cell gene expression. The results revealed an upregulation of the CD36 gene, which is associated with the HPV-induced oncogenic pathways, including PI3K-Akt and p53 signaling pathway. qRT-PCR analysis further identified that the upregulation of the CD36 gene due to the expression of HPV16 E7.

Conclusion

The successful expression of HPV16 E7 in cells demonstrates that the replicated recombinant virus retains the replication and infection abilities of Ad4, while also upregulating the CD36 gene involved in the PI3K-Akt signaling and p53 pathways, thereby promoting cell proliferation. The outcome of this study provides a novel perspective and serves as a solid foundation for further exploration of HPV-related carcinogenesis and the development of replicative HPV recombinant vaccines capable of inducing protective immunity against HPV.

A pan-cancer analysis of FAT atypical cadherin 4 (FAT4) in human tumors

Objective

We performed a pan-cancer analysis to explore the potential mechanisms of FAT4 in 33 different tumors.

Methods

In this study, we selected 33 types of cancers based on the datasets of TCGA (the cancer genome atlas). We analyzed the expression of FAT4 in tumor and normal tissues. Meanwhile, we analyzed the expression levels of FAT4 in tissues from tumors of different stages. Kaplan-Meier survival analysis, Tumor Mutational Burden (TMB), Microsatellite Instability (MSI), immune infiltration analysis, Gene set enrichment analysis (GSEA), and FAT4-related gene enrichment analysis were performed.

Results

FAT4 expression in most tumor tissues was lower than in corresponding control tissues. FAT4 expression was different in different stages of bladder cancer (BLCA), kidney clear cell carcinoma (KIRC), and breast cancer (BRCA). In addition, the expression level of FAT4 in different types of tumors has an important impact on the prognosis of patients. FAT4 might influence the efficacy of immunotherapy via tumor burden and microsatellite instability. We observed a statistically positive correlation between cancer-associated fibroblasts and FAT4 expression in most tumors. GSEA of BLCA indicated that low FAT4 expression groups were mainly enriched in calcium signaling pathway and chemokine signaling pathway. GSEA analysis of KIRC suggested low FAT4 expression groups were mainly involved in olfactory transduction and oxidative phosphorylation. Kyoto Encyclopedia of Genes and Genomes (KEGG) indicated that the role of FAT4 in the pathogenesis of cancer may be related to human papillomavirus infection, Hippo signaling pathway, PI3K-Akt signaling pathway, etc. Gene Ontology (GO) enrichment analysis further showed that most of these genes were related to the pathways or cell biology, such as peptidyl-tyrosine phosphorylation, cell junction assembly, protein tyrosine kinase activity, etc.

Conclusion

Our study summarized and analyzed the antitumor effect of FAT4 in different tumors comprehensively, which aided in understanding the role of FAT4 in tumorigenesis from the perspective of clinical tumor samples. Pan-cancer analysis showed that FAT4 to be novel biomarkers for various cancers prognosis.