Zhixiong Cai

Galectin-4 serves as a prognostic biomarker for the early recurrence / metastasis of hepatocellular carcinoma

Galectin‐4 is a multifunctional lectin found at both intracellular and extracellular sites. It could serve as a tumor suppressor intracellularly and promote tumor metastases extracellularly during colorectal cancer development. However, galectin‐4 expression and its prognostic value for patients with hepatocellular carcinoma (HCC) have not been well investigated. Here we report that galectin‐4 was significantly downregulated in early recurrent/metastatic HCC patients, when compared to non‐recurrent/metastatic HCC patients. Low expression of gelectin‐4 was well associated with larger tumor size, microvascular invasion, malignant differentiation, more advanced TNM stage, and poor prognosis. Cancer cell migration and invasion could be significantly reduced through overexpression of galectin‐4, but upregulated by knocking down of galectin‐4 in vitro. Moreover, the serum galectin‐4 level could be significantly elevated solely by hepatitis B virus infection. Combined with clinicopathological features, the higher serologic level of galectin‐4 was well associated with more aggressive characteristics of HCC. Taken together, galectin‐4 expression closely associates with HCC progression and might have potential use as a prognostic biomarker for HCC patients.

Tumor Microenvironment Activable Self-Assembled DNA Hybrids for pH and Redox Dual-Responsive Chemotherapy/PDT Treatment of Hepatocellular Carcinoma

Smart self‐assembled “Turn‐ON” DNA hybrids are employed, which could respond to tumor microenvironment stimuli for cancer cell specific real‐time fluorescence imaging, tumor‐specific synergistic photodynamic therapy and chemotherapy in hepatocellular carcinoma.

Horseradish peroxidase and aptamer dual-functionalized nanoprobe for the amplification detection of alpha-methylacyl-CoA racemase.

Alpha-methylacyl-CoA racemase (AMACR) is over-expressed in many cancer types and can serve as a novel diagnostic biomarker. Development of convenient and sensitive detection methods of AMACR is of particular importance for cancer diagnosis. Aptamers are a type of recognition elements, which possess many advantages over antibody, making them suitable for applications in biosensing and biotechnology. In this work, we use the efficient surface modification of gold nanoparticles (AuNPs) to prepare the horseradish peroxidase (HRP) and aptamer dual-functionalized nanoprobe. The immobilization of HRP and thiol-terminated aptamer on the surface of AuNPs can be achieved through electrostatic interaction and the formation of Au-S bond, respectively. This nanoprobe, which is used as discriminating and catalytic probe, can be combined with enzyme immunoassay method to increase the detection sensitivity of AMACR. The detection limit can reach as low as 4.6 pg mL(-1) due to the dual signal amplification from enzymatic cycling and the high loading of enzymes on AuNPs. This sensitivity is about three orders of magnitude higher than that of AMACR aptamer based fluorescence method, which is also comparable to or one order of magnitude higher than that of ELISA. Furthermore, this method is more simple and effective, which not only avoids the conjugation between recognition element and the catalytic enzyme, but also achieves greater signal amplification. This assay could be used as a sensitive and selective platform for the detection of target protein.

α-Methylacyl-CoA racemase (AMACR) serves as a prognostic biomarker for the early recurrence/metastasis of HCC

Aims Hepatocellular carcinoma (HCC) is one of the most common malignancies worldwide, and it is still lacking effective prognostic biomarkers so far. Previous results of the iTRAQ-based quantitative proteomics study (iTRAQ-2DLC-MS/MS) have shown that α-methylacyl-CoA racemase (AMACR) might be a promising prognostic biomarker for the early recurrence/metastasis of hepatocellular carcinoma (HCC). Here a large-scale cohort clinical study was performed to evaluate its prognostic potential. Methods HCC samples from patients (n=158) were used for the construction of tissue microarray. The expression level of AMACR was determined by immunohistochemical staining. A large-scale cohort clinical study between the expression of AMACR and some major clinical parameter has been performed to assess the prognostic potential of AMACR for the early recurrence/metastasis of HCC. Results Some important clinical parameters such as α-fetoprotein, tumour numbers, dissemination to regional lymph nodes, tumour capsule and portal vein tumour thrombosis are significantly associated with the low expression of AMACR. The expression of AMACR was an independent factor for the survival of patients with HCC. The median survival time was 17 months in the low-expression group compared with 45 months in the high-expression group. Conclusions This study reveals that the AMACR might be a potential prognostic marker for predicting early recurrence/metastasis of HCC after hepatectomy.

Chemotherapeutic Drug Based Metal-Organic Particles for Microvesicle-Mediated Deep Penetration and Programmable pH/NIR/Hypoxia Activated Cancer Photochemotherapy

Abstract A novel metal–organic particle (MOP) based nanodrug formed by mild self‐assembly of chemotherapeutic drugs, including banoxantrone and doxorubicin, through Cu(II)‐mediated coordination effects, is reported. In this nanodrug, Cu(II) acts as a bridge to join AQ4N and DOX, and then, self‐assembly of [‐AQ4N‐Cu(II)‐(DOX)2‐Cu(II)‐]n complexes forms nanosized MOPs (referred to as ADMOPs) through multiple interactions including host–metal–guest coordination, hydrophobic interactions, π‐stacking, and van der Waals force. The ADMOPs reported here have several important features over conventional drugs, including tumor microenvironment pH‐sensitive drug release that can be tracked by “turning on” the fluorescence of AQ4N or DOX through proton competition with Cu(II) to break the coordination bonds and much deeper penetration into solid tumors via microvesicle‐mediated intercellular transfer. Most strikingly, the ADMOPs can serve as stimuli‐responsive nanocarriers to efficiently load the photosensitizer phthalocyanine due to their inherent highly porous characteristics. Thus, the ADMOPs significantly enhance the chemotherapeutic efficacy by “on‐demand” photodynamic therapy, which further induces a hypoxic environment that enhances the reduction of AQ4N to systematically increase the therapeutic efficiency. Taken together, the designed ADMOPs composed of chemotherapeutic drugs may serve as a potential programmable controlled synergistic agent for cancer therapy.

Overexpression of annexin A4 indicates poor prognosis and promotes tumor metastasis of hepatocellular carcinoma

The prognosis of hepatocellular carcinoma (HCC) after surgical resection remains unsatisfactory for the majority of HCC patients who developed early recurrence or metastasis. There is still a lack of reliable biomarkers that can be used to predict the possibility of recurrence/metastasis in HCC patients after operation. In the current study, annexin A4, a calcium-dependent phospholipid-binding protein, has been found to be significantly elevated in HCC patients with early recurrence/metastasis, and had a strong correlation with portal vein tumor thrombosis (p = 0.03) and advanced BCLC stage (p = 0.002). Cox proportional hazards regression analysis revealed that annexin A4 was an independent prognostic predictor for both early recurrence/metastasis (HR = 1.519, p = 0.032) and overall survival (HR = 1.827, p = 0.009) after surgical resection. Meanwhile, Kaplan–Meier analysis showed that Patients with high-expression levels of annexin A4 had higher recurrence rate and shorter overall survival than those with low expression (log-rank test, p < 0.001). Furthermore, in vitro studies have demonstrated that overexpression of annexin A4 facilitated HCC cell migration and invasion via regulating epithelial–mesenchymal transition (EMT). In conclusion, annexin A4 has played important roles in the progression of HCC, and might act as a potential prognostic biomarker for HCC.

Adipose tissue-derived stem cells promote the reversion of non-alcoholic fatty liver disease: An in vivo study

Non-alcoholic fatty liver disease (NAFLD) is the most common cause of liver injury and seriously affects human health. In the present study, we aimed to investigate whether adipose tissue-derived stem cell (ADSC) transplantation in combination with dietary modification was capable of reversing the progression of NAFLD. After establishing a rat model of NAFLD by feeding them a high-fat diet (HFD), ADSCs were transplanted via the portal vein into rats with HFD-induced NAFLD, and simultaneously fed a modified diet. Thereafter, gross liver morphology, the hepatosomatic (HSI) index and indicators of liver function, including alanine aminotransferase (ALT), aspartate aminotransferase (AST) and total bilirubin (TBIL) were evaluated. Subsequently, the serum levels of total cholesterol (TC), triglycerides (TGs) and fatty acids (FAs) were also assayed. Furthermore, H&E and oil red O staining were used to confirm the pathological effects of NAFLD in the rat livers. Although dietary modification alone caused liver function to recover, ADSC transplantation in combination with dietary modification further decreased the HSI index, the serum levels of ALT, TBIL, TC, TGs, FAs, reduced lipid accumulation to normal levels, and reversed the hepatic pathological changes in the rat livers. Taken together, these findings suggest that ADSC transplantation assists in the reversion of NAFLD by improving liver function and promoting lipid metabolism, thereby exerting hepatoprotective effects. Thus, we suggest that ADSC transplantation is a promising, potential therapeutic strategy for NAFLD treatment.

Polydopamine-assisted versatile modification of a nucleic acid probe for intracellular microRNA imaging and enhanced photothermal therapy

MicroRNAs play an important role in various biological processes, and their aberrant expression is closely associated with various human diseases, especially cancer. Real-time monitoring of microRNAs in living cells may help us to understand their role in cellular processes, which can further provide a basis for diagnosis and treatment. In this study, polydopamine was used to assist the versatile modification of a nucleic acid probe for intracellular microRNA imaging and enhanced photothermal therapy. Polydopamine can be covalently linked with a thiol-terminated nucleic acid probe through the Michael addition reaction under slightly alkaline conditions. This modification is mild and can be performed directly in an aqueous solution, which can better resist hydrolysis than the traditional modification processes, resulting in a nanoprobe with better stability and higher loading of nucleic acids. This prepared nanoprobe can easily enter cells without transfection agents and then realize the imaging of intracellular miRNA through fluorescence restoration. Moreover, the coating of PDA can enhance the photothermal conversion efficiency of the nanoprobe, making it suitable for photothermal therapy of cancer. It is expected that the PDA-based versatile modification can help to construct a promising platform for tumor imaging and treatment.

Co-culture system of hepatocytes and endothelial cells: two in vitro approaches for enhancing liver-specific functions of hepatocytes

Although hepatocyte transplantation and bioartificial liver support system provide new promising opportunities for those patients waiting for liver transplantation, hepatocytes are easily losing liver-specific functions by using the common in vitro cultured methods. The co-culture strategies with mimicking the in vivo microenvironment would facilitate the maintenance of liver-specific functions of hepatocytes. Considering that hepatocytes and endothelial cells (ECs) account for 80–90% of total cell populations in the liver, hepatocytes and ECs were directly co-cultured with hepatic stellate cells (HSCs) or adipose tissue-derived stem cells (ADSCs) at a ratio of 700:150:3 or 14:3:3 in the present study, and the liver-specific functions were carefully analyzed. Our results showed that the two co-culture systems presented the enhanced liver-specific functions through promoting secretion of urea and ALB and increasing the expressions of ALB, CYP3A4 and HNF4α, and the vessel-like structure in the co-culture system consisted of hepatocytes, ECs and ADSCs. Hence, our results suggested that the directly co-culture of hepatocytes and ECs with HSCs or ADSCs could significantly improve liver-specific functions of hepatocytes, and the co-culture system could further promote angiogenesis of ECs at a later stage. Therefore, this study provides potential interesting in vitro strategies for enhancing liver-specific functions of hepatocytes.

Photo-responsive hollow silica nanoparticles for light-triggered genetic and photodynamic synergistic therapy

The development of multifunctional carriers incorporating genetic and photodynamic therapy (PDT) for synergistic antitumor treatment has attracted intensive interests very recently. However, most of the currently reported systems employ passive gene release strategies depending on tumor microenvironment, which are negatively affected by the heterogeneity of cancer cells, thus resulting in limited controllability in therapeutic progress. Herein, a novel photo-responsive hollow silica nanoparticle (HNP)-based gene and photosensitizer (PS) co-delivery nanovehicle is designed for dual-wavelength light-triggered synergistic gene and PDT therapy. The resultant HNP conjugated with PDMAEMA polycation through a 405-nm light-cleavable Cou-linker, namely, HNP-Cou-PD, exhibits excellent gene condensation capacity, good biocompatibility, outstanding PS loading ability, and light-triggered gene release properties. HNP-Cou-PD with Chlorin e6 (Ce6) loaded inside the silica cavity and a plasmid encoding caspase-8 gene (CSP8) attached to the PDMAEMA outside layer (Ce6-HNP-Cou-PD/CSP8) has been proven to possess better antitumor effects under the irradiation of pre-405-nm and post-670-nm light both in vitro and in vivo because of the light-triggered intracellular gene release and reactive oxygen species (ROS) generation. Therefore, HNP-Cou-PD designed as a gene and PS co-delivery carrier might have promising applications in the future to precisely treat various types of cancers. STATEMENT OF SIGNIFICANCE Multifunctional carriers incorporating genetic and photodynamic therapy (PDT) have drawn intense attention very recently, ascribing to their enhanced anticancer effects. However, in the present gene and PDT synergistic system, gene release strategies passively relying on tumor microenvironment often result in no or poor controllability compared with PDT (a spatial and temporal therapeutic modal), which may hinder their synergistic efficacy, especially in an on-demand manner. To resolve this problem, we designed a hollow silica nanoparticle-based dual-wavelength light-responsive gene and photosensitizer (PS) co-delivery platform to achieve photo-triggered gene and PDT synergistic therapy. We believe that our work may have extensive application prospects in precise treatment of various cancers and be of interest to the readership.