Zebularine potentiates anti-tumor immunity by inducing tumor immunogenicity and improving antigen processing through cGAS-STING pathway.

DNA methylation is an important epigenetic mechanism involved in the anti-tumor immune response, and DNA methyltransferase inhibitors (DNMTi) have achieved impressive therapeutic outcomes in patients with certain cancer types. However, it is unclear how inhibition of DNA methylation bridges the innate and adaptive immune responses to inhibit tumor growth. Here, we report that DNMTi zebularine reconstructs tumor immunogenicity, in turn promote dendritic cell maturation, antigen-presenting cell activity, tumor cell phagocytosis by APCs, and efficient T cell priming. Further in vivo and in vitro analyses reveal that zebularine stimulates cGAS-STING-NF-κB/IFNß signaling to enhance tumor cell immunogenicity and upregulate antigen processing and presentation machinery (AgPPM), which promotes effective CD4+ and CD8+ T cell-mediated killing of tumor cells. These findings support the use of combination regimens that include DNMTi and immunotherapy for cancer treatment.

Unveiling the Role of Protein Kinase C θ in Porcine Epidemic Diarrhea Virus Replication: Insights from Genome-Wide CRISPR/Cas9 Library Screening.

Porcine epidemic diarrhea virus (PEDV), a member of the Alpha-coronavirus genus in the Coronaviridae family, induces acute diarrhea, vomiting, and dehydration in neonatal piglets. This study aimed to investigate the genetic dependencies of PEDV and identify potential therapeutic targets by using a single-guide RNA (sgRNA) lentiviral library to screen host factors required for PEDV infection. Protein kinase C θ (PKCθ), a calcium-independent member of the PKC family localized in the cell membrane, was found to be a crucial host factor in PEDV infection. The investigation of PEDV infection was limited in Vero and porcine epithelial cell-jejunum 2 (IPEC-J2) due to defective interferon production in Vero and the poor replication of PEDV in IPEC-J2. Therefore, identifying suitable cells for PEDV investigation is crucial. The findings of this study reveal that human embryonic kidney (HEK) 293T and L929 cells, but not Vero and IPEC-J2 cells, were suitable for investigating PEDV infection. PKCθ played a significant role in endocytosis and the replication of PEDV, and PEDV regulated the expression and phosphorylation of PKCθ. Apoptosis was found to be involved in PEDV replication, as the virus activated the PKCθ-B-cell lymphoma 2 (BCL-2) ovarian killer (BOK) axis in HEK293T and L929 cells to increase viral endocytosis and replication via mitochondrial apoptosis. This study demonstrated the suitability of HEK293T and L929 cells for investigating PEDV infection and identified PKCθ as a host factor essential for PEDV infection. These findings provide valuable insights for the development of strategies and drug targets for PEDV infection.

Long Non-coding RNA LINC01224 Promotes the Malignant Behaviors of Triple Negative Breast Cancer Cells via Regulating the miR-193a-5p/NUP210 Axis.

Triple negative breast cancer (TNBC) is a prevalent malignant tumor in women and is characterized by high incidence and mortality. Current evidence has suggested that multiple long noncoding RNAs (lncRNAs) play regulatory roles in TNBC, while the specific mechanism of LINC01224 in TNBC remains unclear. In this study, LINC01224 was highly expressed in TNBC cells. Moreover, LINC01224 downregulation inhibited TNBC cell proliferation, migration, and invasion, and promoted cell apoptosis. Additionally, LINC01224 stabilized NUP210 mRNA through interaction with miR-193a-5p, thereby aggravating the malignant phenotypes of TNBC. Overall, LINC01224 functions as a tumor promoter for TNBC.

LncRNA SNHG11 aggravates cell proliferation and migration in triple-negative breast cancer via sponging miR-2355-5p and targeting CBX5.

Triple-negative breast cancer (TNBC) is one of the most common malignances worldwide. Concurrently, the incidence of TNBC has continued to rise in recent years. It is reported that long non-coding RNAs (lncRNAs) are involved in biological processes in numerous cancers including TNBC. Small nucleolar RNA host gene 11 (SNHG11) has already been studied and reported in some cancers. However, the role of SNHG11 in TNBC remains unknown. RT-qPCR was used to measure gene expression in the current study. CCK-8, colony formation, flow cytometry, Transwell and western blotting experiments were also performed to determine the biological function of SNHG11 in TNBC cells. Luciferase reporter and RIP assays were performed to measure relationship between genes. In the present study, the results indicated SNHG11 was highly expressed in TNBC tissues and cell lines. Moreover, SNHG11 aggravated cell proliferation and migration, and whereas it attenuated cell apoptosis in TNBC. Furthermore, SNHG11 sponged microRNA 2355-5p (miR-2355-5p) in TNBC. Silencing SNHG11 increased miR-2355-5p expression. In addition, chromobox 5 (CBX5) was identified to be targeted by miR-2355-5p in TNBC. It was also suggested that CBX5 silencing suppressed cell proliferation and migration. Furthermore, overexpressed CBX5 recovered the inhibitive influence of SNHG11 silencing on proliferative and migrative abilities of TNBC cells. Overall, SNHG11 acted as a tumor promoter in TNBC and regulated TNBC cell growth by modulating the miR-2355-5p/CBX5 axis, which indicated that it may be used as a biomarker for TNBC treatment.

MiR-370-5p inhibits the progression of breast cancer via targeting LUC7L3.

Breast cancer is one of the most common malignancies and one of the leading causes of cancer-induced mortality among women. Over the past decades, the occurrence of breast cancer has been a significant increase. As documented in numerous researches, microRNAs (miRNAs) play vital roles in a wide range of biological processes associated with the occurrence and development of breast cancer. Nevertheless, the role of miR-370-5p in breast cancer remains obscure, and the possible molecular regulatory mechanism needs to be further explored. In this study, our results delineated that miR-370-5p was downregulated in breast cancer tissues and cell lines. Besides, miR-370-5p overexpression suppressed cell proliferation and invasion in breast cancer. MiR-370-5p downregulation exerted an opposite result. In addition, LUC7L3 was identified as a target gene for miR-370-5p. Similar with the results induced by miR-370-5p overexpression, LUC7L3 knockdown attenuated the proliferation and invasion ability of breast cancer cells. Moreover, the alternation of LUC7L3 expression reversed the regulatory effects of miR-370-5p on cell phenotypes in breast cancer. Overall, miR-370-5p may exert antitumor effect on breast cancer. Hence, miR-370-5p may serve as a novel therapeutic marker for the treatment of patients with breast cancer.

Activation of lncRNA lnc-SLC4A1-1 induced by H3K27 acetylation promotes the development of breast cancer via activating CXCL8 and NF-kB pathway.

This study aimed to investigate the effect and potential modulation mechanism of lnc-SLC4A1-1 on breast cancer (BC) carcinogenesis. The expression of lnc-SLC4A1-1 in tissue and serum samples from BC patients, as well as BC cell lines, was detected by real-time quantitative reverse transcription-polymerase chain reactions (qRT-PCRs). Next, the expression of lnc-SLC4A1-1 was silenced or upregulated in BC cells, then cell proliferation, apoptosis, migration and invasion were detected using MTT, flow cytometry analysis and Transwell assay. Meanwhile, the expression of apoptosis-related proteins and epithelial-mesenchymal transition-related proteins were detected by western blotting. Furthermore, potential mechanism of lnc-SLC4A1-1 was explored by chromatin immunoprecipitation and RNA immunoprecipitation assays. CXCL8 was overexpressed to evaluate the relationship between lnc-SLC4A1-1 and CXCL8. Lnc-SLC4A1-1 was significantly up-regulated in BC tissue, serum samples and cell lines. In BC cells, lnc-SLC4A1-1 knockdown promoted cell apoptosis and suppressed cell proliferation, migration and invasion. Furthermore, lnc-SLC4A1-1 is transcriptionally activated by H3K27 acetylation, and lnc-SLC4A1-1 interacted with transcription factor (NF)-κB p65, thereby regulating CXCL8 expression. Meanwhile, CXCL8 overexpression partly reversed the effects of lnc-SLC4A1-1 knockdown on cell viability, apoptosis, migration and invasion in BC cells. Lnc-SLC4A1-1 could promote the development of BC by regulating NF-κB/CXCL8. Highlights Lnc-SLC4A1-1 was overexpressed in BC tissues, blood and cell lines. Lnc-SLC4A1-1 was transcriptionally activated by H3K27 acetylation. Lnc-SLC4A1-1 interacted with NF-κB to promote CXCL8 expression. Lnc-SLC4A1-1 could promote the development of BC.

MicroRNA-1270 modulates papillary thyroid cancer cell development by regulating SCAI.

PURPOSE: We intended to evaluate expression and mechanisms of human microRNA 1270 (hsa-miR-1270) in papillary thyroid cancer (PTC). METHODS: In PTC cell lines and human PTC tumors, hsa-miR-1270 expressions were evaluated by qRT-PCR. Hsa-miR-1270 was downregulated in TPC1 and K1 cells via lentiviral transduction. Its effects on PTC cancer cell proliferation, migration and in vivo transplantation were assessed, respectively. Potential targeting of hsa-miR-1270 on downstream gene, Suppressor Of Cancer Cell Invasion (SCAI), was assessed. In hsa-miR-1270-downregulated PTC cells, SCAI was further downregulated to examine its associating role in hsa-miR-1270-mediated regulation on cancer cell proliferation and migration. RESULTS: Hsa-miR-1270 was aberrantly upregulated in PTC cell lines and human PTC tumors. In TPC1 and K1 cells, lentivirus-mediated hsa-miR-1270 downregulation suppressed cancer cell proliferation, migration and in vivo transplantation. Hsa-miR-1270 binds SCAI and inversely regulated SCAI gene expression in PTC cells. SCAI downregulation removed the suppressing effects of hsa-miR-1270 downregulation in human PTC cells. CONCLUSION: Hsa-miR-1270 downregulation may suppress human PTC cell development both in vitro and in vivo. The regulatory mechanism of hsa-miR-1270 in PTC may be primarily associated with SCAI.