Although COVID-19 has become a major challenge to global health, there are currently no efficacious agents for effective treatment. Cytokine storm syndrome (CSS) can lead to acute respiratory distress syndrome (ARDS), which contributes to most COVID-19 mortalities. Research points to interleukin 6 (IL-6) as a crucial signature of the cytokine storm, and the clinical use of the IL-6 inhibitor tocilizumab shows potential for treatment of COVID-19 patient. In this study, we challenged wild-type and adenovirus-5/human angiotensin-converting enzyme 2-expressing BALB/c mice with a combination of polyinosinic-polycytidylic acid and recombinant SARS-CoV-2 spike-extracellular domain protein. High levels of TNF-α and nearly 100 times increased IL-6 were detected at 6 h, but disappeared by 24 h in bronchoalveolar lavage fluid (BALF) following immunostimulant challenge. Lung injury observed by histopathologic changes and magnetic resonance imaging at 24 h indicated that increased TNF-α and IL-6 may initiate CSS in the lung, resulting in the continual production of inflammatory cytokines. We hypothesize that TNF-α and IL-6 may contribute to the occurrence of CSS in COVID-19. We also investigated multiple monoclonal antibodies (mAbs) and inhibitors for neutralizing the pro-inflammatory phenotype of COVID-19: mAbs against IL-1α, IL-6, TNF-α, and granulocyte-macrophage colony-stimulating factor (GM-CSF), and inhibitors of p38 and JAK partially relieved CSS; mAbs against IL-6, TNF-α, and GM-CSF, and inhibitors of p38, extracellular signal-regulated kinase, and myeloperoxidase somewhat reduced neutrophilic alveolitis in the lung. This novel murine model opens a biologically safe, time-saving avenue for clarifying the mechanism of CSS/ARDS in COVID-19 and developing new therapeutic drugs.

Statins comprise a class of prescription drugs used for reducing cholesterol. Evidence has also showed that statins could reduce cancer incidence. However, the anti-tumor mechanism of statins has not been fully defined. Here, we found that atorvastatin inhibited proliferation of esophageal squamous cell carcinoma (ESCC) cells. The underlying mechanisms were explored by mass spectrometry. The proteome data revealed that atorvastatin inhibited the cAMP and Rap1 signal pathways, except for Ras signal pathway. Interestingly, phosphoproteome profiles suggested that ERKT185/Y187, CDK1T14, and BRAC1S1189 phosphorylation–mediated Th17 cell differentiation, Gap junction and the Platinum drug resistance pathway were down-regulated after atorvastatin treatment. The phosphorylation levels of ERKT185/Y187, CDK1T14 and BRAC1S1189 were confirmed by western blotting in KYSE150 cells. More importantly, atorvastatin suppresses ESCC tumor growth in PDX models. The molecular changes in tumor tissues were confirmed by immunohistochemistry. In conclusion, deep-proteome and phosphoproteome analysis reveal a comprehensive mechanism that contributes to atorvastatin’s anti-tumor effect.

The high incidence and mortality of esophageal squamous cell cancer (ESCC) is a major health problem worldwide. Precancerous lesions of ESCC may either progress to cancer or revert to normal epithelium with appropriate interventions; the bidirectional instability of the precancerous lesions of ESCC provides opportunities for intervention. Reports suggest that the upregulation of ornithine decarboxylase (ODC) is closely related to carcinogenesis. In this study, we investigated whether ODC may act as a target for chemoprevention in ESCC. Immunohistochemistry (IHC) assays indicate that ODC expression is higher in esophageal precancerous lesions compared with normal tissue controls. Its overexpression promotes cell proliferation and transformation of normal esophageal epithelial cells, and its activity is increased after N‐nitrosomethylbenzylamine (NMBA) induction in Shantou human embryonic esophageal cell line (SHEE) and human immortalized cells (Het1A) cells. In addition, p38 α, extracellular regulated kinase (ERK1/2) in the mitogen‐activated protein kinase pathway and protein kinase B (AKT)/mammalian target of rapamycin (mTOR)/ribosomal protein S6 kinase (p70S6K) pathways are activated in response to NMBA treatment. Difluoromethylornithine (DFMO) is an ODC inhibitor, which inhibits NMBA‐induced activation of p38 α, ERK1/2 and AKT/mTOR/p70S6K pathways; this has been verified by Western blotting. DFMO was also found to suppress the development of esophageal precancerous lesions in an NMBA‐induced rat model; IHC demonstrated p38 α, ERK1/2, and AKT/mTOR/p70S6K pathways to be downregulated in these rats. These findings indicate the mechanisms by which ODC inhibition suppresses the development of esophageal precancerous lesions by downregulating p38 α, ERK1/2, and AKT/mTOR/p70S6k signaling pathways, ODC may be a potential target for chemoprevention in ESCC.

AbstractCOVID-19 has become a major challenge to global health, and until now, no efficient antiviral agents have been developed. The SARS-CoV-2 infection is characterized by pulmonary and systemic inflammation in severe patients, and acute respiratory distress syndrome (ARDS) caused respiratory failure contributes to most mortalities. There is an urgent need for developing effective drugs and vaccines against SARS-CoV-2 and COVID-19 caused ARDS. However, most researchers cannot perform SARS-CoV-2 related researches due to lacking P3 or P4 facility. We developed a non-infectious, highly safety, time-saving SARS-CoV-2 components induced murine model to study the SARS-CoV-2 caused ARDS and cytokine storm syndrome (CSS). We also investigated mAbs and inhibitors which potentially neutralize the pro-inflammatory phenotype of COVID-19, and found that anti-IL-1α, anti-IL-6, anti-TNFα, anti-GM-CSF mAbs, p38 inhibitor, and JAK inhibitor partially relieved CSS. Besides, anti-IL-6, anti-TNFα, anti-GM-CSF mAbs and inhibitors of p38, ERK, and MPO somewhat reduced neutrophilic alveolitis in the lung. In all, we established the murine model mimic of COVID-19, opening a biosafety and less time-consuming avenue for clarifying the mechanism of ARDS and CSS in COVID-19 and developing the therapeutic drugs.

The overexpression of intratumoral Prohibitin 1 (PHB1), an evolutionarily conserved gene, has been associated with a 5‐year survival rate of less than 35% in muscle‐invasive bladder cancer patients. When localized to the mitochondria, PHB1 promotes tumor cell proliferation by supporting mitochondrial integrity, whereas nuclear PHB1 assists in inducing cell cycle arrest. As the subcellular localization of PHB1 dictates its function, the mechanisms governing the change in PHB1’s subcellular localization could be exploited to develop novel cancer therapeutics. PHB1 has a mitochondrial signal sequence, but previous work suggested that phosphorylation of PHB1 by Akt at Thr258 is required for mitochondrial localization. Our study confirms and expands this work by using immunofluorescence microscopy to visualize the subcellular location of PHB1 in a muscle‐invasive bladder cancer cell line (5637) after the use of Akt inhibitors. Akt inhibition liberated PHB1 from the mitochondria causing a significant increase in nuclear localization. However, blocking Akt disrupts multiple cellular processes, including those involving the function of PHB1, presenting a potentially confounding explanation for these results. To negate the off‐target effects of Akt inhibition, site‐directed mutagenesis was used to create two mutant PHB1 cDNA plasmids. In the first plasmid, Thr258 was mutated into an aspartate, T258D, which mimics Akt phosphorylation. The second mutation created an alanine, T258A, non‐phosphorylatable. Transfection of T258D showed elevated mitochondrial localization of PHB1, while non‐phosphorylatable T258A pooled in the cytoplasm and failed to enter the mitochondria. Therefore, we concluded that phosphorylation of Thr258 by Akt increases the mitochondrial localization of PHB1. Support or Funding Information R.J. McElroy Trust Student/Faculty Research FundWartburg College Undergraduate Research FundWartburg College Biology DepartmentMany generous donors to the Group Alpha Research Fund