Dual-reporter fluorescent probe for precise identification of liver cancer by sequentially responding to carboxylesterase and polarity.

Early treatment significantly improves the survival rate of liver cancer patients, so the development of early diagnostic methods for liver cancer is urgent. Liver cancer can develop from viral hepatitis, alcoholic liver, and fatty liver, thus making the above diseases share common features such as elevated viscosity, reactive oxygen species, and reactive nitrogen species. Therefore, accurate differentiation between other liver diseases and liver cancer is both a paramount practical need and challenging. Numerous fluorescent probes have been reported for the diagnosis of liver cancer by detecting a single biomarker, but these probes lack specificity for liver cancer in complex biological systems. Obviously, using multiple liver cancer biomarkers as the basis for judgment can dramatically improve diagnostic accuracy. Herein, we report the first fluorescent probe, LD-TCE, that sequentially detects carboxylesterase (CE) and lipid droplet polarity in liver cancer cells with high sensitivity and selectivity, with linear detection of CE in the range of 0-6 U/mL and a 65-fold fluorescence enhancement in response to polarity. The probe first reacts with CE and releases weak fluorescence, which is then dramatically enhanced due to the decrease in lipid droplet polarity in liver cancer cells. This approach allows the probe to enable specific imaging of liver cancer with higher contrast and accuracy. The probe successfully achieved the screening of liver cancer cells and the precise identification of liver cancer in mice. More importantly, it is not disturbed by liver fibrosis, which is a common pathological feature of many liver diseases. We believe that the LD-TCE is expected to be a powerful tool for early diagnosis of liver cancer.

A highly sensitive Golgi-targeted fluorescent probe for the simultaneous detection of malondialdehyde and formaldehyde in living systems and foods.

Malondialdehyde (MDA) and formaldehyde (FA) are highly active carbonyl substances widely present in both biological and abiotic systems. The detection of MDA and FA is of great significance for disease diagnosis and food safety monitoring. However, due to the similarity in structural properties between MDA and FA, very few probes for synergistically detecting MDA and FA were reported. In addition, functional abnormalities in the Golgi apparatus are closely related to MDA and FA, but currently there are no fluorescent probes that can detect MDA and FA in the Golgi apparatus. Therefore, we constructed a simple Golgi-targetable fluorescent probe GHA based on hydrazine moiety as the recognition site to produce a pyrazole structure after reaction with MDA and to generate a CN double bond after reaction with FA, allowing MDA and FA to be distinguished due to different emission wavelengths during the recognition process. The probe GHA has good specificity and sensitivity. Under the excitation of 350 nm, the blue fluorescence was significantly enhanced at 424 nm when the probe reacted with MDA, and the detection limit was 71 nM. At the same time, under the same excitation of 350 nm, the reaction with FA showed a significant enhancement of green fluorescence at 520 nm, with a detection limit of 12 nM for FA. And the simultaneous and high-resolution imaging of MDA and FA in the Golgi apparatus of cells was achieved. In addition, the applications of the probe GHA in food demonstrated it can provide a powerful method for food safety monitoring. In summary, this study offers a promising tool for the synergistic identification and determination of MDA and FA in the biosystem and food, facilitating the revelation of their detailed functions in Golgi apparatus and the monitoring of food safety.

Clinical value of circulating tumour cells in evaluating the efficacy of continuous hepatic arterial infusion among colorectal cancer patients.

Few studies have been conducted to evaluate the efficacy of HAIC using circulating tumour cells (CTCs). In this study, a total of 100 patients who received HAIC treatment and CTC detection were selected. The results showed that after HAIC treatment, the levels of CTC, carbohydrate antigen 19-9 (CA19-9) and carcinoembryonic antigen (CEA) decreased. Postoperative progression-free survival (PFS) rates between patients with positive and negative preoperative CTC results, and for CA19-9, CEA were significantly different. The positive rate of CTCs was 61% before chemotherapy and 23% after chemotherapy, and the correlation coefficient between the two was 0.385. Those whose CTC values increased after chemotherapy had shorter PFS rates. CTCs are an independent predictor of recurrence. Patients with CTC-positive results are more susceptible to recurrence. The CTC count in peripheral blood has a close bearing on the postoperative chemotherapy efficacy of patients with CRC and affects patients' PFS.

ATF3/EGR1 regulates myocardial ischemia/reperfusion injury induced autophagy and inflammation in cardiomyocytes.

Myocardial ischemia/reperfusion injury (MIRI) is an irreversible adverse event during the management of coronary heart disease that lacks effective controls. The underlying mechanism of MIRI still requires further investigation. Recent studies have suggested that overexpression of ATF3 protects against MIRI by regulating inflammatory responses, ferroptosis, and autophagy. The downstream target of ATF3, EGR1, also showed cardioprotective properties against MIRI by promoting autophagy. Therefore, further investigating the effect of ATF3/EGR1 pathway on MIRI-induced inflammation and autophagy is needed. Cardiomyocyte MIRI model was established by challenging H9C2 cells with hypoxia/reoxygenation (H/R). The ATF3 overexpression-H/R cell model by transfecting ATF3 plasmid into the H9C2 cell line. The transcription levels of ATF3 and EGR1 were determined using RT-qPCR, the levels of TNF-α and IL-6 were determined using ELISA kits, the protein expression of LC3 I, LC3 II, and P62 was determined via WB, and microstructure of H9C2 cell was observed by transmission electron microscopy (TEM). Overexpression of ATF3 significantly downregulated Egr1 levels, indicating that EGR1 might be the target of ATF3. By upregulating ATF3 levels, the extracellular levels of the inflammatory cytokines TNF-α and IL-6 significantly decreased, and the protein expression of the autophagy markers LC3 I, LC3 II, and P62 significantly increased. TEM results revealed that the cell line in the H/R-ATF3 group exhibited a higher abundance of autophagosome enclosures of mitochondria. The results indicated that ATF3/EGR1 may alleviate inflammation and improve autophagy in an H/R-induced MIRI model of cardiomyocytes.

The mechanisms of tumor necrosis factor α in regulating Krüpple-like factor 4 expression in SK-BR-3 breast cancer cells.

OBJECTIVE: To explore the expression and functional role of Krüpple-like factor 4 (KLF4) protein stimulated by tumor necrosis factor α (TNF-α) in SK-BR-3 breast cancer cells. METHODS: SK-BR-3 cells were stimulated with various concentrations of TNF-α at 0, 1, 5, 10, and 20 ng/mL. Expression levels of KLF4 protein were detected by Western blotting. In the detection of apoptosis, flow cytometry, and DAPI staining were used for detecting the level of apoptosis. RESULTS: KLF4 expression was markedly elevated following stimulation of SK-BR-3 with TNF-α. At the same time, the expression of KLF4 protein increased gradually with the increase of TNF-α stimulation concentration. TNF-α stimulation of SK-BR-3 cells increased apoptosis as measured by apoptosis levels. By overexpressing KLF4 protein in SK-BR-3 cells, it similarly increased apoptosis and promoted cell death of SK-BR-3 cells. CONCLUSION: TNF-α promotes KLF4 expression, while TNF-α promotes apoptosis in SK-BR-3 cells, a process that may be due to elevated KLF4 protein expression.

ABCG2 is an itaconate exporter that limits antibacterial innate immunity by alleviating TFEB-dependent lysosomal biogenesis.

Itaconate is a metabolite that synthesized from cis-aconitate in mitochondria and transported into the cytosol to exert multiple regulatory effects in macrophages. However, the mechanism by which itaconate exits from macrophages remains unknown. Using a genetic screen, we reveal that itaconate is exported from cytosol to extracellular space by ATP-binding cassette transporter G2 (ABCG2) in an ATPase-dependent manner in human and mouse macrophages. Elevation of transcription factor TFEB-dependent lysosomal biogenesis and antibacterial innate immunity are observed in inflammatory macrophages with deficiency of ABCG2-mediated itaconate export. Furthermore, deficiency of ABCG2-mediated itaconate export in macrophages promotes antibacterial innate immune defense in a mouse model of S. typhimurium infection. Thus, our findings identify ABCG2-mediated itaconate export as a key regulatory mechanism that limits TFEB-dependent lysosomal biogenesis and antibacterial innate immunity in inflammatory macrophages, implying the potential therapeutic utility of blocking itaconate export in treating human bacterial infections.

Recent advances in small-molecule fluorescent probes with the function of targeting cancer receptors.

Cancer is "the sword of Damocles" that threatens human life and health. Therefore, the diagnosis and treatment of cancer have been receiving much attention. Many overexpressed receptors on the surface of cancer cells provide us with an effective way to specifically identify the cancer cells, and receptor targeting strategies are becoming one of the hot ideas to enhance the ability of fluorescent probes to target tumors. Fluorescent probes connected to ligands are targeted at cancer cell surfaces through receptor-mediated endocytosis. Receptor-targeting probes can image and track cancer cells, determine tumor boundaries, monitor deep lesions, and play a role in clinical medicine, such as fluorescent imaging-guided surgery. In this review, based on the perspective of small molecule fluorescent probes, we reviewed the design ideas, photophysical properties, and applications of receptor-targeting probes for detecting biomarkers in imaging and tracing cancer cells and prospected the future developmental direction of such probes. We hope that this review will provide more ideas for the design and development of active targeting probes for receptors and lead to more applications in the medical field.

Anti-PRL-3 Monoclonal Antibody inhibits the Growth and Metastasis of colorectal adenocarcinoma.

Background: Colon cancer is the one of leading causes of cancer-related death. Chemotherapy, radiotherapy and immunotherapy will be the mainstream in inoperable advanced cancer in clinics. Precision treatment is still lack in colon cancer. Materials and Methods: We developed a series of mAbs targeting PRL-3 through different types of immunogens. The binding domains of mAbs were identified through the ELISA and Western blotting experiments. The antitumor activity of mAbs was verified by cell proliferation, migration and invasion experiments. Xenograft subcutaneous and metastatic models and patient derived Xenograft (PDX) model were established. Results: mAb 12G12 targeting 77-120AA exhibited inhibition in migration and invasion experiments. 12G12 inhibited the migration of multiple types of cancer cells, including colon cancer, gastric cancer, esophagus cancer, liver cancer, lung cancer and pancreatic cancer cells. 12G12 decreased the tumor growth and metastasis in Xenograft subcutaneous and metastatic tumor model, respectively. The antitumor activity of mAb 12G12 was also confirmed in PDX model of gastric cancer. PRL-3 interacted with Golgi protein TMED10. Knockdown of TMED10 expression attenuated the cell migration triggered by purified GST-PRL-3 protein. Conclusion: Our results confirmed the antitumor activity of mAb 12G12 in colorectal adenocarcinoma and provided a new potential targeted therapy of colon cancer.

Multifunctional Theranostic Probe Based on the Pim-1 Kinase Inhibitor with the Function of Tracking pH Fluctuations during Treatment.

Currently, kinase inhibitors have been applied in the diagnosis or treatment of cancer with their unique advantages. It is of great significance to develop some comprehensive theranostic reagents based on kinase inhibitors to improve the performance of reagents for biomedical applications. Besides, tracking changes in the intracellular environment (e.g., pH) during cancer development and drug delivery is also critical for cancer research and treatment. Therefore, it is an urgent desire to design some novel multifunctional reagents based on kinase inhibitor strategies that can trace changes in the microenvironment of cancer cells. In this paper, a multifunctional theranostic reagent based on Pim-1 kinase inhibitor 5-bromobenzofuran-2-carboxylic acid is proposed. The theranostic probe binds to tumor-specific Pim-1 kinase, releases strong fluorescence, and produces cytotoxicity, thus achieving cell screening and killing effects. Furthermore, the probe can specifically target lysosomes and sensitively respond to pH. It can be used to track the pH changes in the intracellular environment under conditions of autophagy and external stimulation, as a visual tool to monitor pH fluctuations during cancer treatment. In conclusion, this simple but multifunctional theranostic reagent proposed in this work is expected to provide a promising method for cancer diagnosis and therapy.

Early-onset pancreatic neuroendocrine neoplasms: A distinct disease with improved survival compared with old individuals.

Background: The incidence, clinicopathologic characteristics, treatment patterns, and survival of early-onset pancreatic neuroendocrine neoplasms (EOPanNENs) have not been well explored. Methods: Patients diagnosed with PanNENs were identified from the SEER database between 2000 and 2018. EOPanNENs were defined as diagnosis in patients aged less than 50 years, while the remaining were defined as later-onset pancreatic neuroendocrine neoplasms (LOPanNENs). Incidence, clinical features, management, and prognosis were analyzed in our study. Multivariable analyses were performed to identify factors associated with overall survival (OS) in EOPanNENs and LOPanNENs, respectively. Results: A total of 5172 patients with PanNENs were included: 1267 (24.5%) in the EOPanNENs cohort and 3905 (75.5%) in the LOPanNENs cohort. The age-adjusted incidence rate significantly increased among later-onset cases, while it remained relatively stable in early-onset cases. EOPanNENs were more frequently to be female, unmarried, and with better tumor differentiation compared with LOPanNENs. Of note, early-onset patients presented with a higher rate of lymph node involvement, and they were more likely to receive surgical treatment. For local-regional disease at presentation, surgery alone was the most frequently used regimen over the last two decades. With regard to distant stage, a combination of surgery and chemotherapy was more often utilized. Risk factors for PanNENs survival were more correlated with LOPanNENs compared with EOPanNENs. The OS and cancer-specific survival (CSS) were significantly better in the EOPanNENs group. Further analyses showed that EOPanNENs ≤ 2cm were associated with more favorable survival outcomes than EOPanNENs>2cm. Conclusion: EOPanNENs are a clinically rare and distinct entity from LOPanNENs. The advantages in survival for the EOPanNENs cohort over time were largely driven by the indolent clinical courses including better tumor differentiation and intensified surgical treatment. Further investigations are warranted to better understand the characteristics of this disease subgroup.

A novel GSH-activable theranostic probe containing kinase inhibitor for synergistic treatment and selective imaging of tumor cells.

Theranostic probe is becoming a powerful tool for diagnosis and treatment of cancer. Although some theranostic probes have been successfully developed, there is still a great room for improvement in sensitive diagnosis and efficient treatment. Herein, we developed a novel GSH-activable theranostic probe NC-G, which uses 1,8-naphthalimide-4-sulfonamide as a fluorescence imaging group and crizotinib as a highly toxic kinase inhibitor to tumor cells. The probe not only has high sensitivity (DL = 74 nM) and specificity, but also can detect GSH sensitively in cells and zebrafish. In addition, probe NC-G can not only show more obvious fluorescence in tumor cells to achieve sensitive diagnosis of tumor cells, but also release the inhibitor crizotinib to achieve high toxicity to tumor cells. It is worth noting that the consumption of GSH can cause oxidative stress response of cells and the release of SO2 can induce cell apoptosis during the recognition process of the probe and GSH. Thus, the synergistic effect of crizotinib, GSH depletion, and SO2 release provides a highly effective therapeutic feature for tumor cells. Therefore, probe NC-G can serve as an excellent theranostic probe for sensitive imaging and highly effective treatment of tumor cells.

H2S-activated fluorescent probe enables dual-channel fluorescence tracking of drug release in tumor cells.

Nowadays, the selective release of therapeutic drugs into tumor cells has become an important way of tumor treatment due to the high side effects of chemotherapy drugs. As one of the gas mediators, hydrogen sulfide (H2S) is closely related to cancer. Due to the high content of H2S in tumor cells, it can be used as a signaling molecule that triggers the release of drugs to achieve the selective release of therapeutic drugs. In addition, dual-channel fluorescence imaging technology can be better applied to monitor the drug delivery process and distinguish the state before and after drug release, so as to better track the effect of drug therapy. Based on this, we used NBD amines (NBD-NHR) as the recognition group of H2S and connected the tyrosine kinase inhibitor crizotinib to construct an activated dual-channel fluorescent probe CZ-NBD. After the probe enters the tumor cells, it consumes H2S and releases crizotinib, which is highly toxic to the tumor cells. Importantly, the probe displays significant fluorescence changes in different cells, enabling not only the screening of tumor cells, but also tracking and monitoring drug release and tumor cell activity. Therefore, the construction of probe CZ-NBD provides a new strategy for drug release monitoring in tumor cells.

Anti-PAI-1 Monoclonal Antibody Inhibits the Metastasis and Growth of Esophageal Squamous Cell Carcinoma.

Plasminogen activator inhibitor (PAI-1) is highly expressed in esophageal squamous cell carcinoma (ESCC) and strongly contributes to metastasis, making it a potential target for ESCC therapy. However, the antibodies and inhibitors targeting PAI-1 have not shown good therapeutic effect in the in vivo experiments yet. Here, we generated a panel of novel monoclonal antibodies (mAbs) against PAI-1. Analysis of PAI-1 expression in 90 tissue specimens and 128 serum specimens from ESCC patients with these mAbs confirmed that PAI-1 levels was significantly correlated with metastasis and poor survival. In addition, we found that high PAI-1 expression contributed to the enhanced motility and invasiveness of two ESCC cell lines. Next, mAb-1E2 and mAb-2E3, which have highest affinity with PAI-1, were shown to possess strong inhibitory effects on ESCC migration and invasion. Anti-tumor and anti-metastatic effects of mAb-2E3 were further demonstrated in the experimental animal models. Finally, LRP1 was identified as key factor mediating the pro-invasive function of PAI-1 and the anti-invasive capacity of mAb-2E3 in ESCC cells. The mAb-2E3 markedly decreased STAT1 phosphorylation levels and blocked the binding between PAI-1 and LRP1-ClusterII domain. Collectively, mAb-2E3 developed by our lab may be an effective antibody drug which can be used for anti-metastatic therapy in ESCC.

Aiphanol, a multi-targeting stilbenolignan, potently suppresses mouse lymphangiogenesis and lymphatic metastasis.

The high incidence of lymphatic metastasis is closely related to poor prognosis and mortality in cancers. Potent inhibitors to prevent pathological lymphangiogenesis and lymphatic spread are urgently needed. The VEGF-C-VEGFR3 pathway plays a vital role in driving lymphangiogenesis and lymph node metastasis. In addition, COX2 in tumor cells and tumor-associated macrophages (TAMs) facilitates lymphangiogenesis. We recently reported that aiphanol, a natural stilbenolignan, attenuates tumor angiogenesis by repressing VEGFR2 and COX2. In this study, we evaluated the antilymphangiogenic and antimetastatic potency of aiphanol using in vitro, ex vivo and in vivo systems. We first demonstrated that aiphanol directly bound to VEGFR3 and blocked its kinase activity with an half-maximal inhibitory concentration (IC50) value of 0.29 µM in an in vitro ADP-GloTM kinase assay. Furthermore, we showed that aiphanol (7.5-30 µM) dose-dependently counteracted VEGF-C-induced proliferation, migration and tubular formation of lymphatic endothelial cells (LECs), which was further verified in vivo. VEGFR3 knockdown markedly mitigated the inhibitory potency of aiphanol on lymphangiogenesis. In 4T1-luc breast tumor-bearing mice, oral administration of aiphanol (5 and 30 mg· kg-1 ·d-1) dose-dependently decreased lymphatic metastasis and prolonged survival time, which was associated with impaired lymphangiogenesis, angiogenesis and, interestingly, macrophage infiltration. In addition, we found that aiphanol decreased the COX2-dependent secretion of PGE2 and VEGF-C from tumor cells and macrophages. These results demonstrate that aiphanol is an appealing agent for preventing lymphangiogenesis and lymphatic dissemination by synergistically targeting VEGFR3 and inhibiting the COX2-PGE2-VEGF-C signaling axis.

A multi-targeting natural product, aiphanol, inhibits tumor growth and metastasis.

Cancer is one of the main causes of death in humans worldwide, the development of more effective anticancer drugs that can inhibit the malignant progression of cancer cells is of great significance. Aiphanol is a natural product identified from the seeds of Arecaceae and the rhizome of Smilax glabra Roxb. Our preliminary studies revealed that it had potential antiangiogenic and antilymphangiogenic activity by directly targeting VEGFR2/3 and COX2 in endothelial cells. However, the influence of aiphanol on cancer cells per se remains largely undefined. In this study, the effects and related mechanisms of aiphanol on cancer growth and metastasis were evaluated in vitro and in vivo. Acute toxicity assay and pharmacokinetic analysis were utilized to investigate the safety profile and metabolism characteristics of aiphanol. We revealed that aiphanol inhibited the proliferation of various types of cancer cells and the growth of xenograft tumors in mice and zebrafish models. The possible mechanism was associated with the inactivation of multiple kinases, including FAK, AKT and ERK, and the upregulation of BAX and cleaved caspase-3 to promote cancer cell apoptosis. Aiphanol significantly inhibited cancer cell migration and invasion, which was related to the inhibition of epithelial-mesenchymal transition (EMT) and F-actin aggregation. Aiphanol effectively attenuated the metastasis of several types of cancer cells in vivo. In addition, aiphanol exerted no significant toxicity and had fast metabolism. Collectively, we demonstrated the anticancer effects of aiphanol and suggested that aiphanol has potential as a safe and effective therapeutic agent to treat cancer.

A genetically encoded fluorescent biosensor for detecting itaconate with subcellular resolution in living macrophages.

Itaconate is a newly discovered endogenous metabolite promoting an anti-inflammatory program during innate immune response, but the precise mechanisms underlying its effect remains poorly understood owing primarily to the limitations of available itaconate-monitoring techniques. Here, we develop and validate a genetically encoded fluorescent itaconate biosensor, BioITA, for directly monitoring itaconate dynamics in subcellular compartments of living macrophages. Utilizing BioITA, we monitor the itaconate dynamics in response to lipopolysaccharide (LPS) stimulation in the context of modulating itaconate transportation and metabolism. Moreover, we show that STING activation induces itaconate production, and injection of AAVs expressing cytosolic BioITA into mice allows directly reporting elevation of itaconate level in activated macrophages derived from LPS-injected mice. Thus, BioITA enables subcellular resolution imaging of itaconate in living macrophages.

ATF4-dependent fructolysis fuels growth of glioblastoma multiforme.

Excessive consumption of fructose in the Western diet contributes to cancer development. However, it is still unclear how cancer cells coordinate glucose and fructose metabolism during tumor malignant progression. We demonstrate here that glioblastoma multiforme (GBM) cells switch their energy supply from glycolysis to fructolysis in response to glucose deprivation. Mechanistically, glucose deprivation induces expression of two essential fructolytic proteins GLUT5 and ALDOB through selectively activating translation of activating transcription factor 4 (ATF4). Functionally, genetic or pharmacological disruption of ATF4-dependent fructolysis significantly inhibits growth and colony formation of GBM cells in vitro and GBM growth in vivo. In addition, ATF4, GLUT5, and ALDOB levels positively correlate with each other in GBM specimens and are poor prognostic indicators in GBM patients. This work highlights ATF4-dependent fructolysis as a metabolic feature and a potential therapeutic target for GBM.

A novel ratiometric fluorescent probe for the detection of nickel ions in the environment and living organisms.

Nickel resources are abundant in the world, and the application of nickel in production and life is more and more extensive. However, excessive nickel entering the environment will not only cause environmental pollution but also seriously endanger plants, animals and human health. Nickel compounds are carcinogenic and have been classified as a class 1 carcinogen. Nickel mainly exists in the form of divalent ions in the environment. However, there are few simple and effective methods for the detection of nickel ions, and these methods still have certain limitations. At present, the mechanisms of nickel influence in organisms are also unclear. Therefore, we constructed a ratiometric fluorescent probe Ra-Ni, which can achieve its own self-calibration and avoid the interference of other factors, thereby realizing the specific identification of nickel ions. The probe can detect nickel ions sensitively with a detection limit as low as 26.2 nM and can respond in a short time (< 2 min), which proves the great potential of the probe in the detection of nickel ions. At the same time, Ra-Ni has also been successfully used for imaging nickel ions in living cells and zebrafish, providing an effective tool for the study of physiological and pathological processes. The detection effect of nickel ions in actual water sample is also satisfactory, which further demonstrates the practicability of Ra-Ni in environmental applications.

Concise Biothiol-Activatable HPQ-NBD Conjugate as a Targeted Theranostic Probe for Tumor Cells.

Cancer, as a malignant tumor, seriously endangers human health. The study of cancer diagnosis and therapy has great practical significance. The development of theranostic agents has become a very important research topic. Nevertheless, some existing agents still have imperfections, such as complex structures and difficult syntheses. Therefore, it is urgent for researchers to develop simple novel theranostic agents. In this study, the precipitated fluorophore HAPQ was used as a simple drug molecule for the first time and combined with NBD-Cl to construct a simple and efficient theranostic probe (HAPQ-NBD). The theranostic probe can distinguish between tumor cells and normal cells based on the higher levels of biothiol in tumor cells. In addition, the probe can use biothiol as a control switch to release higher levels of precipitated fluorophore HAPQ in tumor cells, leading to selective high toxicity to tumor cells, thus achieving the goal of selectively killing tumor cells. The construction of probe HAPQ-NBD provides a practical tool for the diagnosis and therapy of cancer. It is expected that the development and utilization of precipitated fluorophore will provide a new method and strategy for cancer diagnosis and therapy.

A new-type HOCl-activatable fluorescent probe and its applications in water environment and biosystems.

The outbreak and spread of Corona Virus Disease 2019 (COVID-19) has led to a significant increase in the consumption of sodium hypochlorite (NaOCl) disinfectants. NaOCl hydrolyzes to produce hypochlorous acid (HOCl) to kill viruses, which is a relatively efficient chlorine-based disinfectant commonly used in public disinfection. While people enjoy the convenience of NaOCl disinfection, excessive and indiscriminate use of it will affect the water environment and threaten human health. Importantly, HOCl is an indispensable reactive oxygen species (ROS) in human body. Whether its concentration is normal or not is closely related to human health. Excessive production of HOCl in the body contributes to some inflammatory diseases and even cancer. Also, we noticed that the concentration of ROS in cancer cells is about 10 times higher than that in normal cells. Herein, we developed a HOCl-activatable biotinylated dual-function fluorescent probe BTH. For this probe, we introduced biotin on the naphthalimide fluorophore, which increased the water solubility and enabled the probe to aggregate in cancer cells by targeting specific receptor overexpressed on the surface of cancer cell membrane. After reacting to HOCl, the p-aminophenylether moiety of this probe was oxidatively removed and the fluorescence of the probe was recovered. As expected, in the PBS solution with pH of 7.4, BTH could give full play to the performance of detecting HOCl, and it has made achievements in detecting the concentration of HOCl in actual water samples. Besides that, BTH had effectively distinguished between cancer cells and normal cells through a dual-function discrimination strategy, which used biotin to enrich the probe in cancer cells and reacted with overexpressed HOCl in cancer cells. Importantly, this dual-function discrimination strategy could obtain the precision detection of cancer cells, thereby offering assistance for improving the accuracy of early cancer diagnosis.