Although our most recent studies have identified Isorhapontigenin (ISO), a novel derivative of stilbene that isolated from a Chinese herb Gnetum cleistostachyum, for its inhibition of human bladder cancer (BC) growth, nothing is known whether ISO possesses an inhibitory effect on BC invasion. Thus, we addressed this important question in current study and discovered that ISO treatment could inhibit mouse invasive BC development following bladder carcinogen N-butyl-N- (4-hydroxybutyl) nitrosamine (BBN) exposure in vivo. We also found that ISO suppressed human BC cell invasion accompanied by up-regulation of the forkhead box class O 1 (FOXO1) mRNA transcription in vitro. Accordingly, FOXO1 was profoundly down-regulated in human BC tissues, and was negatively correlated with BC invasion. Forced expression of FOXO1 specifically suppressed high grade human BC cell invasion, while knockdown of FOXO1 promoted non-invasive BC cells becoming invasive BC cells. Moreover, knockout of FOXO1 significantly increased BC cell invasion and abolished the ISO inhibition of invasion in human BC cells. Further studies showed that the inhibition of STAT1 phosphorylation at Tyr701 was crucial for ISO up-regulation of FOXO1 transcription. Furthermore, this study revealed that metalloproteinase-2 (MMP-2) was a FOXO1 downstream effector, which was also supported by data obtained from mouse model of ISO inhibition BBN-induced mouse invasive BC formation. These findings not only provide a novel insight into the understanding of mechanism of BC’s propensity to invasion, but also identify a new role and mechanisms underlying the natural compound ISO that specifically suppresses such BC invasion through targeting the STAT1-FOXO1-MMP2 axis.

The outbreak of coronavirus disease 2019 (COVID-19), caused by the novel coronavirus severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has caused a threat to global health. The mortality rate of severely ill patients in the early stage is 32.5%. The exacerbation of the condition and death of patients are closely associated with inflammatory cytokine storms, which are caused by excessive activation of the immune and complement systems as well as the coinfection of other pathogens. However, the immunological characteristics and the mechanisms underlying inflammatory storms have not been well elucidated. Here, we analyzed the clinical and immunological characteristics of 71 confirmed COVID-19 patients. Based on the National Health Commission of China (NHCC) guidelines, patients were stratified into mild and severe types. We compared the clinical and laboratory data obtained from electronic medical records between the two types. In regard to the hematological parameters, COVID-19 patients showed decreased erythrocyte count, hemoglobin, hematocrit, lymphocyte count, eosinophil count, and complement C1q, whereas neutrophils, C-reactive protein, and procalcitonin were significantly increased, especially in severe cases. We also found that CD3+ CD4+ T lymphocytes, CD3+ CD8+ T lymphocytes, CD19+ B lymphocytes, and CD16+ CD56+ NK cells in the peripheral blood of all patients were decreased. In addition, CD3+ CD8+ T lymphocytes, CD16+ CD56+ NK cells, and complement C1q in severely ill patients decreased more significantly. Additionally, interleukin 6 (IL-6) elevation was particularly prominent in all patients, especially in severe cases. These results suggest that CD3+ CD8+ T lymphocytes, CD16+ CD56+ NK cells, C1q as well as IL-6 may play critical roles in the inflammatory cytokine storm. The dysregulation of these aforementioned immune parameters, along with bacterial coinfection, were the important causes of exacerbation of the patients’ condition and death. This study improves our understanding of the immune dysregulation of COVID-19 and provides potential immunotherapeutic strategies. IMPORTANCE The dysregulation of CD3+ CD8+ T lymphocytes, CD16+ CD56+ NK cells, C1q as well as IL-6, along with bacterial coinfection, were important causes of exacerbation of the patients’ condition and death.

Our recent studies found that isorhapontigenin (ISO) showed a significant inhibitory effect on human bladder cancer cell growth, accompanied with cell cycle G0/G1 arrest as well as down-regulation of Cyclin D1 expression at transcriptional level via inhibition of Sp1 transactivation in bladder cancer cells. In current studies, the potential ISO inhibition of bladder tumor formation has been explored in xenograft nude mouse model, and the molecular mechanisms underlying ISO inhibition of Sp1 expression and anti-cancer activities has been elucidated both in vitro and in vivo. Moreover, the studies demonstrated that ISO treatment induced the expression of miR-137, which in turn suppressed Sp1 protein translation by direct targeting Sp1 mRNA 3′UTR. Similar to ISO treatment, ectopic expression of miR-137 alone led to G0/G1 cell growth arrest and inhibition of anchorage-independent growth in human bladder cancer cells, which could be completely reversed by over-expression of GFP-Sp1. The inhibition of miR-137 expression attenuated ISO-induced the inhibition of Sp1/Cyclin D1 expression, and induction of G0/G1 cell growth arrest and suppression of cell anchorage-independent growth. Taken together, our studies have demonstrated that miR-137 induction by ISO targets Sp1 mRNA 3′UTR and inhibits Sp1 protein translation, which consequently results in reduction of Cyclin D1 expression, induction of G0/G1 growth arrest and inhibition of anchorage-independent growth in vitro and in vivo. Our results have provided novel insights into understanding the anti-cancer activity of ISO in the therapy of human bladder cancer.

Purpose The carcinogenic capacity of B[a]P/B[a]PDE is supported by epidemiologic studies. However, the molecular mechanisms responsible for B[a]P/B[a]PDE-caused lung cancer have not been well investigated. We evaluated here the role of novel target PHLPP2 in lung inflammation and carcinogenesis upon B[a]P/B[a]PDE exposure. Experimental Design We used the Western blotting, RT-PCR, [35S]methionine pulse and immunohistochemistry staining to determine PHLPP2 downregulation following B[a]P/B[a]PDE exposure. Both B[a]PDE-induced Beas-2B cell transformation model and B[a]P-caused mouse lung cancer model were used to elucidate the mechanisms leading to PHLPP2 downregulation and lung carcinogenesis. The important findings were also extended to in vivo human studies. Results We found that B[a]P/B[a]PDE exposure downregulated PHLPP2 expression in human lung epithelial cells in vitro and in mouse lung tissues in vivo. The ectopic expression of PHLPP2 dramatically inhibited cell transformation upon B[a]PDE exposure. Mechanistic studies showed that miR-205 induction was crucial for inhibition of PHLPP2 protein translation by targeting PHLPP2-3′-UTR. Interestingly, PHLPP2 expression was inversely associated with tumor necrosis factor alpha (TNFα) expression, with low PHLPP2 and high TNFα expression in lung cancer tissues compared with the paired adjacent normal lung tissues. Additional studies revealed that PHLPP2 exhibited its antitumorigenic effect of B[a]P/B[a]PDE through the repression of inflammatory TNFα transcription. Conclusions Our studies not only first time identify PHLPP2 downregulation by lung carcinogen B[a]P/B[a]PDE, but also elucidate a novel molecular mechanisms underlying lung inflammation and carcinogenesis upon B[a]P/B[a]PDE exposure.