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Lipid metabolism rearrangements in nonalcoholic fatty liver disease (NAFLD) contribute to disease progression. NAFLD has emerged as a major risk for hepatocellular carcinoma (HCC), where metabolic reprogramming is a hallmark. Identification of metabolic drivers might reveal therapeutic targets to improve HCC treatment. Here, we investigated the contribution of transcription factors E2F1 and E2F2 to NAFLD-related HCC and their involvement in metabolic rewiring during disease progression. In mice receiving a high-fat diet (HFD) and diethylnitrosamine (DEN) administration, E2f1 and E2f2 expressions were increased in NAFLD-related HCC. In human NAFLD, E2F1 and E2F2 levels were also increased and positively correlated. E2f1 -/- and E2f2 -/- mice were resistant to DEN-HFD-induced hepatocarcinogenesis and associated lipid accumulation. Administration of DEN-HFD in E2f1 -/- and E2f2 -/- mice enhanced fatty acid oxidation (FAO) and increased expression of Cpt2, an enzyme essential for FAO, whose downregulation is linked to NAFLD-related hepatocarcinogenesis. These results were recapitulated following E2f2 knockdown in liver, and overexpression of E2f2 elicited opposing effects. E2F2 binding to the Cpt2 promoter was enhanced in DEN-HFD-administered mouse livers compared with controls, implying a direct role for E2F2 in transcriptional repression. In human HCC, E2F1 and E2F2 expressions inversely correlated with CPT2 expression. Collectively, these results indicate that activation of the E2F1-E2F2-CPT2 axis provides a lipid-rich environment required for hepatocarcinogenesis. SIGNIFICANCE These findings identify E2F1 and E2F2 transcription factors as metabolic drivers of hepatocellular carcinoma, where deletion of just one is sufficient to prevent disease. GRAPHICAL ABSTRACT http//cancerres.aacrjournals.org/content/canres/81/11/2874/F1.large.jpg.Lymph node (LN) metastasis is one of the most malignant clinical features in patients with esophageal squamous cell carcinoma (ESCC). Understanding the mechanism of LN metastasis will provide treatment strategies for ESCC patients. Long noncoding RNAs (lncRNA) play a critical role in the development and progression of human cancers. However, the role and mechanism of lncRNAs in LN metastasis remain largely unknown. Here we show that VEGF-C mRNA stability-associated long noncoding RNA (VESTAR) is involved in LN metastasis of ESCC. VESTAR was overexpressed in ESCC tissues and was predictive of poor prognosis in patients with ESCC. In ESCC, NXF1 and SRSF3 facilitated nuclear export of VESTAR to the cytoplasm, which was associated with LN metastasis. Depletion of VESTAR inhibited ESCC-associated lymphangiogenesis and lymphatic metastasis. Mechanistically, VESTAR directly bound and stabilized VEGF-C mRNA. VESTAR also interacted with HuR, a positive regulator of VEGF-C mRNA stability, and increased HuR binding to VEGF-C mRNA. Our study reveals a novel lncRNA-guided mechanism of LN metastasis in ESCC and may provide a potential target for treatment of ESCC lymphatic metastasis.Current clinical trials of combined EGFR-tyrosine kinase inhibitors (TKIs) and immune checkpoint blockade (ICB) therapies show no additional effect. This raises questions regarding whether EGFR-TKIs attenuate ICB-enhanced CD8+ T lymphocyte function. Here we show that the EGFR-TKI afatinib suppresses CD8+ T lymphocyte proliferation, and we identify CAD, a key enzyme of de novo pyrimidine biosynthesis, to be a novel afatinib target. Afatinib reduced tumor-infiltrating lymphocyte numbers in Lewis lung carcinoma (LLC)-bearing mice. Early afatinib treatment inhibited CD8+ T lymphocyte proliferation in NSCLC patients, but their proliferation unexpectedly rebounded following long-term treatment. This suggests a transient immunomodulatory effect of afatinib on CD8+ T lymphocytes. Sequential treatment of afatinib with anti-PD1 immunotherapy substantially enhanced therapeutic efficacy in MC38 and LLC-bearing mice, while simultaneous combination therapy showed only marginal improvement over each single treatment. These results suggest that afatinib can suppress CD8+ T lymphocyte proliferation by targeting CAD, proposing a timing window for combined therapy that may prevent the dampening of ICB efficacy by EGFR-TKIs.Chemotherapy-induced cognitive impairment (CICI) is often reported as a neurotoxic side effect of chemotherapy. CD38-IN-78c Although CICI has emerged as a significant medical problem, meaningful treatments are not currently available due to a lack of mechanistic understanding underlying CICI pathophysiology. Using the platinum-based chemotherapy cisplatin as a model for CICI, we show here that cisplatin suppresses nicotinamide adenine dinucleotide (NAD+) levels in the adult female mouse brain in vivo and in human cortical neurons derived from induced pluripotent stem cells in vitro. Increasing NAD+ levels through nicotinamide mononucleotide (NMN) administration prevented cisplatin-induced abnormalities in neural progenitor proliferation, neuronal morphogenesis, and cognitive function without affecting tumor growth and anti-tumor efficacy of cisplatin. Mechanistically, cisplatin inhibited expression of the NAD+ biosynthesis rate-limiting enzyme nicotinamide phosphoribosyl transferase (Nampt). Selective restoration of Nampt expression in adult-born neurons was sufficient to prevent cisplatin-induced defects in dendrite morphogenesis and memory function. Taken together, our findings suggest that aberrant Nampt-mediated NAD+ metabolic pathways may be a key contributor in cisplatin-induced neurogenic impairments, thus causally leading to memory dysfunction. Therefore, increasing NAD+ levels could represent a promising and safe therapeutic strategy for cisplatin-related neurotoxicity.Although macrophages (MΦ) are known to play a central role in neuropathic pain, their contribution to cancer pain has not been established. Here we report that depletion of sciatic nerve resident MΦs (rMΦ) in mice attenuates mechanical/cold hypersensitivity and spontaneous pain evoked by intraplantar injection of melanoma or lung carcinoma cells. MΦ-colony stimulating factor (M-CSF) was upregulated in the sciatic nerve trunk and mediated cancer-evoked pain via rMΦ expansion, transient receptor potential ankyrin 1 (TRPA1) activation, and oxidative stress. Targeted deletion of Trpa1 revealed a key role for Schwann cell TRPA1 in sciatic nerve rMΦ expansion and pain-like behaviors. Depletion of rMΦs in a medial portion of the sciatic nerve prevented pain-like behaviors. Collectively, we identified a feed-forward pathway involving M-CSF, rMΦ, oxidative stress and Schwann cell TRPA1 that operates throughout the nerve trunk to signal cancer-evoked pain.