The current COVID-19 pandemic urges the extremely sensitive and prompt detection of SARS-CoV-2 virus. Here, we present a Human Angiotensin-converting-enzyme 2 (ACE2)-functionalized gold “virus traps” nanostructure as an extremely sensitive SERS biosensor, to selectively capture and rapidly detect S-protein expressed coronavirus, such as the current SARS-CoV-2 in the contaminated water, down to the single-virus level. Such a SERS sensor features extraordinary 106-fold virus enrichment originating from high-affinity of ACE2 with S protein as well as “virus-traps” composed of oblique gold nanoneedles, and 109-fold enhancement of Raman signals originating from multi-component SERS effects. Furthermore, the identification standard of virus signals is established by machine-learning and identification techniques, resulting in an especially low detection limit of 80 copies mL−1 for the simulated contaminated water by SARS-CoV-2 virus with complex circumstance as short as 5 min, which is of great significance for achieving real-time monitoring and early warning of coronavirus. Moreover, here-developed method can be used to establish the identification standard for future unknown coronavirus, and immediately enable extremely sensitive and rapid detection of novel virus.
3 August 2020 in Journal of Experimental & Clinical Cancer Research
Background: Collagens are the most abundant proteins in extra cellular matrix and important components of tumor microenvironment. Recent studies have showed that aberrant expression of collagens can influence tumor cell behaviors. However, their roles in hepatocellular carcinoma (HCC) are poorly understood. Methods: In this study, we screened all 44 collagen members in HCC using whole transcriptome sequencing data from the public datasets, and collagen type IV alpha1 chain (COL4A1) was identified as most significantly differential expressed gene. Expression of COL4A1 was detected in HCC samples by quantitative real-time polymerase chain reaction (qRT-PCR), western blot and immunohistochemistry (IHC). Finally, functions and potential mechanisms of COL4A1 were explored in HCC progression. Results: COL4A1 is the most significantly overexpressed collagen gene in HCC. Upregulation of COL4A1 facilitates the proliferation, migration and invasion of HCC cells through FAK-Src signaling. Expression of COL4A1 is upregulated by RUNX1 in HCC. HCC cells with high COL4A1 expression are sensitive to the treatment with FAK or Src inhibitor. Conclusion: COL4A1 facilitates growth and metastasis in HCC via activation of FAK-Src signaling. High level of COL4A1 may be a potential biomarker for diagnosis and treatment with FAK or Src inhibitor for HCC.
The online version contains supplementary material available at 10.1007/s40820-021-00620-8. The online version contains supplementary material available at 10.1007/s40820-021-00620-8.
The treatment of hyperprolactinemia is based on the use of dopamine agonists, mainly bromocriptine (BRC) and cabergoline (CAB). They reduce tumour size effectively and restore gonadal function. However, there is a difference in drug sensitivity between CAB and BRC in patients with prolactinoma, although the underlying mechanisms are still unknown. Thus, we investigated whether there are differences in tumour sensitivity to CAB and BRC and their possible differential mechanisms in two prolactinoma cell lines. In our study, we found that GH3 cells are more sensitive to BRC and that MMQ cells are more sensitive to CAB. Moreover, BRC and CAB elicited cell death via different pathways; BRC induced prolactinoma cell death mainly through the apoptosis pathway, and CAB induced pituitary prolactinoma cell death mainly via the autophagic cell death pathway. Using gene microarray analysis, we found that BRC induces the apoptosis of prolactinoma cells through the ERK/EGR1 signalling pathway, whereas CAB induces autophagic death by inhibiting the AKT/mTOR signalling pathway. Our study showed the difference in tumour sensitivity and differential mechanisms in BRC- and CAB-treated prolactinoma cells, which provides a theoretical basis for the accurate treatment of prolactinoma.
Mutations in epidermal growth factor receptor (EGFR) are the key drivers of lung cancer initiation and recurrence. The cancer cells undergo transformation to a reversible drug‐tolerant persister (DTP) state prior to the development of resistance against EGFR‐tyrosine kinase inhibitors (TKIs). Two DTP lung cancer cells with different proliferative capacities are established and identified dipeptidyl peptidase 4 (DPP4) as a potential therapeutic target. The DTP cells primarily relied on oxidative phosphorylation, which is accompanied by the up‐regulation of fatty acid metabolism. Mechanistically, DPP4 facilitates the uptake of fatty acids via carnitine palmitoyl transferase 1a (CPT1A, and enhances fatty acid oxidation. In addition, the DPP4‐mitogen‐activated protein kinase kinase (MEK)‐Nuclear factor erythroid‐2‐related factor 2 (Nrf2) signaling pathway maintains mitochondrial function by activating the antioxidant pathway. The combination of osimertinib and sitagliptin, a DPP4 inhibitor, not only suppressed tumor progression but also reduced the number of residual tumor cells and minimal residual disease. Notably, this combination therapy significantly lowered recurrence rates and extended the survival of tumor‐bearing mice compared to the monotherapies. The study provides new insights into the metabolic adaptations of DTP lung cancer cells in response to EGFR‐TKIs, offering novel therapeutic strategies for targeting these persister cells.