c-Rel is a Novel Oncogene in Lung Squamous Cell Carcinoma Regulating Cell Proliferation and Migration.

Lung squamous cell carcinoma (LUSC) accounts for approximately 25% to 30% of lung cancers, but largely no targeted therapy is available against it, calling for identification of new oncogenes in LUSC growth for new therapeutic targets. In this study, REL was identified through a screening for oncogenes that are highly amplified in human LUSC. Its expression was associated with poor prognosis in LUSC patients. Furthermore, knockdown of c-Rel in LUSC cell lines lead to significant decrease in cell proliferation and migration. Mechanistically, c-Rel knockdown suppressed NFκB pathway by blocking phosphorylation of IκB. Consistently, pharmaceutic inhibition of c-Rel also. In orthotopic xenograft lung cancer mouse model, c-Rel knockdown inhibited the tumor growth. Cancer cell proliferation and epithelial-mesenchymal-transition (EMT) of the tumors were impaired by c-Rel knockdown. Finally, it's confirmed in precision-cut tumor slices of LUSC that deletion of c-Rel inhibits the NFκB pathway and cancer cell growth. Accordingly, we hypothesize that c-Rel promotes the activation of the NFκB pathway by promoting the phosphorylation of IκB in LUSC. Our study reveals REL as a novel LUSC oncogene and provides new insights into the molecular regulation of LUSC, which will provide new therapeutic targets for the treatment of squamous lung cancer.

LncRNA HHIP-AS1 suppresses lung squamous cell carcinoma by stabilizing HHIP mRNA.

AIMS: Lung squamous cell carcinoma (LUSC) causes over 400,000 deaths annually, yet it lacks targeted therapy. A major antagonist of Hedgehog pathway, HHIP (Hedgehog Interacting Protein) plays an important role in LUSC; however, the regulatory mechanism remains unclear. Long non-coding RNA HHIP-AS1 plays suppressive or promotive roles in different cancers, but its role in LUSC remains unknown. This manuscript is to investigate regulatory mechanism of HHIP and the role of HHIP-AS1 in LUSC. MAIN METHODS: Precision-cut lung slices (PCLS) from human LUSC samples are cultured to mimic LUSC growth. Overexpression and knockdown in multiple LUSC cell lines and PCLS are achieved by lentivirus infection. Transcriptome profile and lung cancer activity are evaluated by RNA-sequencing, immunostaining and CCK8 assay etc. KEY FINDINGS: HHIP is regulated independently of Hh pathway in LUSC. Additionally, downregulation of HHIP-AS1 is associated with poor prognosis. Consistently, HHIP-AS1 inhibits LUSC growth by suppressing cell proliferation and migration. Transcriptome profiling of HHIP-AS1 knockdown (KD) cells uncovered HHIP downregulation. Interestingly, a comparison between the transcriptomes of HHIP-AS1 KD or HHIP KD cells manifested high similarity. Subsequently it's confirmed that HHIP-AS1 regulates HHIP in LUSC cells. Notably, HHIP-AS1 regulation on LUSC growth is achieved through stabilizing HHIP mRNA rather than regulating MIR-153-3P/PCDHGA9 or MIR-425-5P/DNYC1I2. Finally, it's confirmed in PCLS from human LUSC samples that HHIP-AS1 suppresses LUSC via regulating HHIP mRNA. SIGNIFICANCE: This study uncovers HHIP-AS1 as a novel tumor suppressor in LUSC and provides new insights into the molecular regulation of LUSC, which will help developing new therapeutic strategies.

Autophagy induction promoted by m6A reader YTHDF3 through translation upregulation of FOXO3 mRNA.

Autophagy is crucial for maintaining cellular energy homeostasis and for cells to adapt to nutrient deficiency, and nutrient sensors regulating autophagy have been reported previously. However, the role of eiptranscriptomic modifications such as m6A in the regulation of starvation-induced autophagy is unclear. Here, we show that the m6A reader YTHDF3 is essential for autophagy induction. m6A modification is up-regulated to promote autophagosome formation and lysosomal degradation upon nutrient deficiency. METTL3 depletion leads to a loss of functional m6A modification and inhibits YTHDF3-mediated autophagy flux. YTHDF3 promotes autophagy by recognizing m6A modification sites around the stop codon of FOXO3 mRNA. YTHDF3 also recruits eIF3a and eIF4B to facilitate FOXO3 translation, subsequently initiating autophagy. Overall, our study demonstrates that the epitranscriptome regulator YTHDF3 functions as a nutrient responder, providing a glimpse into the post-transcriptional RNA modifications that regulate metabolic homeostasis.

The adenosine analog prodrug ATV006 is orally bioavailable and has preclinical efficacy against parental SARS-CoV-2 and variants.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the virus driving the ongoing coronavirus disease 2019 (COVID-19) pandemic, continues to rapidly evolve. Because of the limited efficacy of vaccination in prevention of SARS-CoV-2 transmission and continuous emergence of variants of concern (VOCs), orally bioavailable and broadly efficacious antiviral drugs are urgently needed. Previously, we showed that the parent nucleoside of remdesivir, GS-441524, has potent anti-SARS-CoV-2 activity. Here, we report that esterification of the 5'-hydroxyl moieties of GS-441524 markedly improved antiviral potency. This 5'-hydroxyl-isobutyryl prodrug, ATV006, demonstrated excellent oral bioavailability in rats and cynomolgus monkeys and exhibited potent antiviral efficacy against different SARS-CoV-2 VOCs in vitro and in three mouse models. Oral administration of ATV006 reduced viral loads and alleviated lung damage when administered prophylactically and therapeutically to K18-hACE2 mice challenged with the Delta variant of SARS-CoV-2. These data indicate that ATV006 represents a promising oral antiviral drug candidate for SARS-CoV-2.