Tuberous sclerosis complex (TSC) is characterized by developmental malformations of the cerebral cortex known as tubers, comprised of cells that exhibit enhanced mammalian target of rapamycin (mTOR) signaling. To date, there are no reports of mTORC1 and mTORC2 activation in fetal tubers or in neural progenitor cells lacking Tsc2. We demonstrate mTORC1 activation by immunohistochemical detection of substrates phospho-p70S6K1 (T389) and phospho-S6 (S235/236), and mTORC2 activation by substrates phospho-PKCα (S657), phospho-Akt (Ser473), and phospho-SGK1 (S422) in fetal tubers. Then, we show that Tsc2 shRNA knockdown (KD) in mouse neural progenitor cells (mNPCs) in vitro results in enhanced mTORC1 (phospho-S6, phospho-4E-BP1) and mTORC2 (phospho-Akt and phospho-NDRG1) signaling, as well as a doubling of cell size that is rescued by rapamycin, an mTORC1 inhibitor. Tsc2 KD in vivo in the fetal mouse brain by in utero electroporation causes disorganized cortical lamination and increased cell volume that is prevented with rapamycin. We demonstrate for the first time that mTORC1 and mTORC2 signaling is activated in fetal tubers and in mNPCs following Tsc2 KD. These results suggest that inhibition of mTOR pathway signaling during embryogenesis could prevent abnormal brain development in TSC.
Cytokines play an important role in the pathogenesis of cirrhosis and hepatocellular carcinoma (HCC), most cases of which are related to either hepatitis B virus (HBV) or hepatitis C virus (HCV). Prior studies have examined differences in individual cytokine levels in patients with chronic liver disease, but comprehensive cytokine profiling data across different clinical characteristics are lacking. We examined serum cytokine profiles of 411 patients with HCC (n = 102: 32% HBV, 54% HCV, 14% non-viral) and without HCC (n = 309: 39% HBV, 39% HCV, 22% non-viral). Multiplex analysis (Luminex 200 IS) was used to measure serum levels of 51 common cytokines. Random forest machine learning was used to obtain receiver operator characteristic curves and to determine individual cytokine importance using Z scores of mean fluorescence intensity for individual cytokines. Among HCC and non-HCC patients, cytokine profiles differed between HBV and HCV patients (area under curve (AUC) 0.82 for HCC, 0.90 for non-HCC). Cytokine profiles did not distinguish cirrhotic HBV patients with and without HCC (AUC 0.503) or HCV patients with and without HCC (AUC 0.63). In conclusion, patients with HBV or HCV infection, with or without HCC, have distinctly different cytokine profiles, suggesting potential differences in disease pathogenesis and/or disease characteristics.
BACKGROUND: African-Americans (AA) have a higher incidence of hepatocellular carcinoma (HCC) and lower survival. We characterized survival rates and clinical features associated with survival in AA vs. Caucasians with HCC over the past two decades. METHODS: HCC patients from three US medical centers were matched by year of diagnosis (1991–2016): AA (n = 578)/Caucasian (n = 578) and placed in one of two groups—HCC diagnosed prior to 2010 or 2010 and after. Data were obtained from chart review and the National Death Index. Multivariate and survival analysis controlling for key predictors were conducted. RESULTS: Prior to 2010, there was no difference in survival between Caucasians and AA (p = 0.61). After 2010, AA patients had poorer survival compared to Caucasians (35% vs. 44%, respectively, p = 0.044). Over time, survival improved for Caucasians (32% before 2010 vs. 44% after 2010, p = 0.003), but not AA (36% vs. 35%, p = 0.50). AA on presentation (in the after 2010 cohort) were more likely to have BCLC (Barcelona Clinic Liver Cancer) stage C (24% vs. 15%, p = 0.010) and less likely to receive treatment (85% vs. 93%, p = 0.002) compared to matched Caucasians. BCLC beyond stage A (aHR: 1.75, 95% CI: 1.26–2.43, p = 0.001) and child’s class C (aHR 2.05, 95% CI: 1.23–3.41, p = 0.006) were the strongest predictors of mortality, while race was not. CONCLUSIONS: African-Americans presented with more advanced HCC and had poorer survival compared to Caucasians after 2010. Tumor stage was an independent predictor of mortality, but ethnicity was not. Further efforts are needed to improve early HCC diagnosis for AA.
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