Interaction between tumor cells and immune cells in the tumor microenvironment is important in cancer development. Immune cells interact with the tumor cells to shape this process. Here, we use ...single-cell RNA sequencing analysis to delineate the immune landscape and tumor heterogeneity in a cohort of patients with HBV-associated human hepatocellular carcinoma (HCC). We found that tumor-associated macrophages suppress tumor T cell infiltration and TIGIT-NECTIN2 interaction regulates the immunosuppressive environment. The cell state transition of immune cells towards a more immunosuppressive and exhaustive status exemplifies the overall cancer-promoting immunocellular landscape. Furthermore, the heterogeneity of global molecular profiles reveals co-existence of intra-tumoral and inter-tumoral heterogeneity, but is more apparent in the latter. This analysis of the immunosuppressive landscape and intercellular interactions provides mechanistic information for the design of efficacious immune-oncology treatments in hepatocellular carcinoma.
Cancer stemness, referring to the stem-cell-like phenotype of cancer cells, has been recognised to play important roles in different aspects of hepatocarcinogenesis. A number of well-established ...cell-surface markers already exist for liver cancer stem cells, with potential new markers of liver cancer stem cells being identified. Both genetic and epigenetic factors that affect various signalling pathways are known to contribute to cancer stemness. In addition, the tumour microenvironment-both physical and cellular-is known to play an important role in regulating cancer stemness, and the potential interaction between cancer stem cells and their microenvironment has provided insight into the regulation of the tumour-initiating ability as well as the cellular plasticity of liver CSCs. Potential specific therapeutic targeting of liver cancer stemness is also discussed. With increased knowledge, effective druggable targets might be identified, with the aim of improving treatment outcome by reducing chemoresistance.
Hepatocellular carcinoma (HCC) is heterogeneous, rendering its current curative treatments ineffective. The emergence of single-cell genomics represents a powerful strategy in delineating the complex ...molecular landscapes of cancers. In this study, we demonstrated the feasibility and merit of using single-cell RNA sequencing to dissect the intra-tumoral heterogeneity and analyze the single-cell transcriptomic landscape to detect rare cell subpopulations of significance. Exploration of the inter-relationship among liver cancer stem cell markers showed two distinct major cell populations according to EPCAM expression, and the EPCAM+ cells had upregulated expression of multiple oncogenes. We also identified a CD24+/CD44+-enriched cell subpopulation within the EPCAM+ cells which had specific signature genes and might indicate a novel stemness-related cell subclone in HCC. Notably, knockdown of signature gene CTSE for CD24+/CD44+ cells significantly reduced self-renewal ability on HCC cells in vitro and the stemness-related role of CTSE was further confirmed by in vivo tumorigenicity assays in nude mice. In summary, single-cell genomics is a useful tool to delineate HCC intratumoral heterogeneity at better resolution. It can identify rare but important cell subpopulations, and may guide better precision medicine in the long run.
•Single-cell transcriptomics dissected the intra-tumoral heterogeneity of hepatocellular carcinoma (HCC).•HCC single cells showed two distinct major cell populations according to EPCAM expression.•CD24+/CD44+-enriched cell subpopulation was identified within the EPCAM+ cells.•CTSE was the most upregulated signature gene in CD24+/CD44+-enriched cells.•Knockdown of CTSE significantly reduced self-renewal ability in vitro and tumorigenicity in vivo.
BACKGROUND AND PURPOSE:The current coronavirus disease 2019 (COVID-19) pandemic represents a global public health crisis, disrupting emergency healthcare services. We determined whether COVID-19 has ...resulted in delays in stroke presentation and affected the delivery of acute stroke services in a comprehensive stroke center in Hong Kong.
METHODS:We retrospectively reviewed all patients with transient ischemic attack and stroke admitted via the acute stroke pathway of Queen Mary Hospital, Hong Kong, during the first 60 days since the first diagnosed COVID-19 case in Hong Kong (COVID-19January 23, 2020–March 24, 2020). We compared the stroke onset to hospital arrival (onset-to-door) time and timings of inpatient stroke pathways with patients admitted during the same period in 2019 (pre–COVID-19January 23, 2019–March 24, 2019).
RESULTS:Seventy-three patients in COVID-19 were compared with 89 patients in pre–COVID-19. There were no significant differences in age, sex, vascular risk factors, nor stroke severity between the 2 groups (P>0.05). The median stroke onset-to-door time was ≈1-hour longer in COVID-19 compared with pre–COVID-19 (154 versus 95 minutes, P=0.12), and the proportion of individuals with onset-to-door time within 4.5 hours was significantly lower (55% versus 72%, P=0.024). Significantly fewer cases of transient ischemic attack presented to the hospital during COVID-19 (4% versus 16%, P=0.016), despite no increase in referrals to the transient ischemic attack clinic. Inpatient stroke pathways and treatment time metrics nevertheless did not differ between the 2 groups (P>0.05 for all comparisons).
CONCLUSIONS:During the early containment phase of COVID-19, we noted a prolongation in stroke onset to hospital arrival time and a significant reduction in individuals arriving at the hospital within 4.5 hours and presenting with transient ischemic attack. Public education about stroke should continue to be reinforced during the COVID-19 pandemic.
To evaluate the effectiveness of a multilevel and multimodal school-based education program.
A cluster randomized controlled trial with 14 secondary schools in Hong Kong and a total of 3713 students ...(intervention: 1545 vs control: 2168; 40.2% boys; mean age ± SD: 14.72 ± 1.53 years) were included in the final analysis. The intervention included a town hall seminar, small class workshops, a slogan competition, a brochure, and an educational Web site. Their parents and teachers were offered sleep education seminars. The control schools did not receive any sleep program. Data were collected before and 5 weeks after the intervention.
The students in the intervention group had significantly improved sleep knowledge compared with the control group (mean difference: 3.64 95% confidence interval (CI): 3.21 to 4.07; Cohen's d = 0.51) as measured by using a sleep knowledge questionnaire. Weekday sleep duration was reduced in both groups, and the significant difference in weekday sleep duration was lost in the intention-to-treat analysis (mean difference: 0:01 95% CI: -0:00 to 0:04). In addition, the intervention group had a lower incidence of consuming caffeine-containing energy drinks (adjusted odds ratio: 0.46 95% CI: 0.22 to 0.99) and had better behavioral (mean difference: -0.56 95% CI: -1.02 to -0.10; Cohen's d = 0.13) and mental health (mean difference: -0.30 95% CI: -0.15 to -0.46; Cohen's d = 0.11) outcomes.
A school-based sleep education program was effective in enhancing sleep knowledge and improving behavioral and mental health, but it had no significant impact on sleep duration or pattern among adolescents.
There is ongoing debate on whether screening for nonalcoholic fatty liver disease (NAFLD) is worthwhile in high‐risk groups. Because of shared risk factors, NAFLD is highly prevalent in patients with ...coronary artery disease. We aimed to test the hypothesis that NAFLD screening in patients requiring coronary angiogram would identify high‐risk patients and predict long‐term clinical outcomes. This was a prospective cohort study. NAFLD screening was performed by abdominal ultrasonography before coronary angiogram in 612 consecutive patients. At baseline, 356 (58.2%) patients had NAFLD. NAFLD patients, compared with those without, were more likely to have >50% stenosis in one or more coronary arteries (84.6% vs. 64.1%; P < 0.001) and therefore require percutaneous coronary intervention (68.3% vs. 43.4%; P < 0.001). During 3,679 patient‐years of follow‐up, 47 (13.2%) NAFLD patients and 59 (23.0%) patients without NAFLD died (age‐ and sex‐adjusted hazard ratio aHR: 0.36; 95% confidence interval CI: 0.18‐0.70; P = 0.003). Composite cardiovascular outcomes (cardiovascular deaths, nonfatal myocardial infarction, heart failure, or secondary interventions) were similar between groups (36.5% vs. 37.1%; aHR, 0.90; 95% CI: 0.69‐1.18). Older age and diabetes were the only independent factors associated with cardiovascular events. Only 2 patients, both in the NAFLD group, died of primary liver cancer. No other patients developed liver‐related complications. Conclusion: In patients with clinical indications for coronary angiogram, the presence of NAFLD is associated with coronary artery stenosis and need for coronary intervention, but not increased mortality or cardiovascular complications. Liver cancer and cirrhotic complications are rare. Our data do not support NAFLD screening in this patient group at present, but studies with a longer duration of follow‐up are needed. (Hepatology 2016;63:754–763)
Background and Aims
Hepatitis B virus (HBV) integrations are common in hepatocellular carcinoma (HCC). In particular, alterations of the telomerase reverse transcriptase (TERT) gene by HBV ...integrations are frequent; however, the molecular mechanism and functional consequence underlying TERT HBV integration are unclear.
Approach and Results
We adopted a targeted sequencing strategy to survey HBV integrations in human HBV‐associated HCCs (n = 95). HBV integration at the TERT promoter was frequent (35.8%, n = 34/95) in HCC tumors and was associated with increased TERT mRNA expression and more aggressive tumor behavior. To investigate the functional importance of various integrated HBV components, we employed different luciferase reporter constructs and found that HBV enhancer I (EnhI) was the key viral component leading to TERT activation on integration at the TERT promoter. In addition, the orientation of the HBV integration at the TERT promoter further modulated the degree of TERT transcription activation in HCC cell lines and patients’ HCCs. Furthermore, we performed array‐based small interfering RNA library functional screening to interrogate the potential major transcription factors that physically interacted with HBV and investigated the cis‐activation of host TERT gene transcription on viral integration. We identified a molecular mechanism of TERT activation through the E74 like ETS transcription factor 4 (ELF4), which normally could drive HBV gene transcription. ELF4 bound to the chimeric HBV EnhI at the TERT promoter, resulting in telomerase activation. Stable knockdown of ELF4 significantly reduced the TERT expression and sphere‐forming ability in HCC cells.
Conclusions
Our results reveal a cis‐activating mechanism harnessing host ELF4 and HBV integrated at the TERT promoter and uncover how TERT HBV‐integrated HCCs may achieve TERT activation in hepatocarcinogenesis.
Hepatocarcinogenesis involves complex genetic and cellular dysregulations which drive the formation of hepatocellular carcinoma (HCC), the predominant form of primary liver cancer, with extensive ...heterogeneity. In contrast to the broad spectrum of molecularly driven therapies available for defined patient groups in certain cancer types, unfortunately the treatment options for HCC are highly limited. The lack of representative molecular and cellular signatures in the heterogeneous HCC tumors that can effectively guide the choice of the most appropriate treatment among the patients unavoidably limits the treatment outcome. Advancement and wide availability of the next-generation sequencing technologies have empowered us to examine and capture not only the detailed genetic alterations of the HCC cells but also the precise composition of different cell types within the tumor microenvironment and their interactions with the HCC cells at an unprecedented level. The information generated has provided new insight and better defined the inter-patient intertumoral heterogeneity, intra-patient intratumoral heterogeneity as well as the plasticity of HCC cells. These collectively provide a robust scientific basis in guiding the development and use of targeted therapy and immunotherapy. To complement, liquid biopsy coupled with high-sensitivity sequencing could potentially be adopted as a more practical and safer approach to detect and reflect the tumor heterogeneity in HCC patients in guiding the choice of treatment and monitoring disease progression.
We investigated the effect and mechanism of hypoxic microenvironment and hypoxia-inducible factors (HIFs) on hepatocellular carcinoma (HCC) cancer stemness.
HCC cancer stemness was analysed by ...self-renewal ability, chemoresistance, expression of stemness-related genes and cancer stem cell (CSC) marker-positive cell population. Specific small ubiquitin-like modifier (SUMO) proteases 1 (SENP1) mRNA level was examined with quantitative PCR in human paired HCCs. Immunoprecipitation was used to examine the binding of proteins and chromatin immunoprecipitation assay to detect the binding of HIFs with hypoxia response element sequence. In vivo characterisation was performed in immunocompromised mice and stem cell frequency was analysed.
We showed that hypoxia enhanced the stemness of HCC cells and hepatocarcinogenesis through enhancing HIF-1α deSUMOylation by SENP1 and increasing stabilisation and transcriptional activity of HIF-1α. Furthermore, we demonstrated that SENP1 is a direct target of HIF-1/2α and a previously unrecognised positive feedback loop exists between SENP1 and HIF-1α.
Taken together, our findings suggest the significance of this positive feedback loop between HIF-1α and SENP1 in contributing to the increased cancer stemness in HCC and hepatocarcinogenesis under hypoxia. Drugs that specifically target SENP1 may offer a potential novel therapeutic approach for HCC.
Vitamin D seems to protect against cardiovascular disease, but the reported effects of vitamin D on patient outcomes in CKD are controversial. We conducted a prospective, double blind, randomized, ...placebo-controlled trial to determine whether oral activated vitamin D reduces left ventricular (LV) mass in patients with stages 3-5 CKD with LV hypertrophy. Subjects with echocardiographic criteria of LV hypertrophy were randomly assigned to receive either oral paricalcitol (1 μg) one time daily (n=30) or matching placebo (n=30) for 52 weeks. The primary end point was change in LV mass index over 52 weeks, which was measured by cardiac magnetic resonance imaging. Secondary end points included changes in LV volume, echocardiographic measures of systolic and diastolic function, biochemical parameters of mineral bone disease, and measures of renal function. Change in LV mass index did not differ significantly between groups (median interquartile range, -2.59 -6.13 to 0.32 g/m(2) with paricalcitol versus -4.85 -9.89 to 1.10 g/m(2) with placebo). Changes in LV volume, ejection fraction, tissue Doppler-derived measures of early diastolic and systolic mitral annular velocities, and ratio of early mitral inflow velocity to early diastolic mitral annular velocity did not differ between the groups. However, paricalcitol treatment significantly reduced intact parathyroid hormone (P<0.001) and alkaline phosphatase (P=0.001) levels as well as the number of cardiovascular-related hospitalizations compared with placebo. In conclusion, 52 weeks of treatment with oral paricalcitol (1 μg one time daily) significantly improved secondary hyperparathyroidism but did not alter measures of LV structure and function in patients with severe CKD.
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