Effects of transforming growth factor β-1 infected human bone marrow mesenchymal stem cells on high- and low-metastatic potential hepatocellular carcinoma

Aggravation of hepatic ischemia‑reperfusion injury with increased inflammatory cell infiltration is associated with the TGF‑β/Smad3 signaling pathway

Ischemia‑reperfusion (IR) injury is a major challenge influencing the outcomes of hepatic transplantation. Transforming growth factor‑β (TGF‑β) and its downstream gene, SMAD family member 3 (Smad3), have been implicated in the pathogenesis of chronic hepatic injuries, such as hepatic fibrosis. Thus, the present study aimed to investigate the role of the TGF‑β/Smad3 signaling pathway on hepatic injury induced by IR in vivo. In total, 20 129S2/SvPasCrl wild‑type (WT) mice were randomized into two groups; 10 mice underwent IR injury surgery and 10 mice were sham‑operated. Histopathological changes in liver tissues and serum levels of alanine aminotransferase (ALT) were examined to confirm hepatic injury caused by IR surgery. The expression levels of TGF‑β1, Smad3 and phosphorylated‑Smad3 (p‑Smad3) were detected via western blotting. Furthermore, a total of five Smad3^‑/‑ 129S2/SvPasCrl mice (Smad3^‑/‑ mice) and 10 Smad3^+/+ littermates received IR surgery, while another five Smad3^‑/‑ mice and 10 Smad3^+/+ littermates received the sham operation. Histopathological changes in liver tissues and serum levels of ALT were then compared between the groups. Furthermore, hepatic apoptosis and inflammatory cell infiltration after IR were evaluated in the liver tissues of Smad3^‑/‑ mice and Smad3^+/+ mice. The results demonstrated that the expression levels of TGF‑β1, Smad3 and p‑Smad3 were elevated in hepatic tissue from WT mice after IR injury. Aggravated hepatic injury, increased apoptosis and enhanced inflammatory cell infiltration induced by hepatic IR injury were observed in the Smad3^‑/‑ mice compared with in Smad3^+/+ mice. Collectively, the current findings suggested that activation of the TGF‑β/Smad3 signaling pathway was present alongside the hepatic injury induced by IR. However, the TGF‑β/Smad3 signaling pathway may have an effect on protecting against liver tissue damage caused by IR injury in vivo.

Protective effect of Salvia miltiorrhiza polysaccharides on liver injury in chickens

This study investigated the effects of Salvia miltiorrhiza polysaccharides (SMPs) on the injury of chicken hepatocytes in vitro and in vivo. In in vitro studies primary cultured hepatocytes were isolated by 2-step collagenase perfusion. Carbon tetrachloride (CCL4) was added to the hepatocytes to establish a hepatocyte injury model. Hepatocytes were treated with different concentrations of SMPs to detect the protective effects of SMPs on CCL4-induced hepatocyte injury. The results of the control group showed that chicken hepatocytes grew well and their morphology was normal. After CCL4 treatment, the activity of alanine transaminase (ALT) and aspartate transaminase (AST) of hepatocytes increased compared with the normal control group. SMPs treatment downregulated the contents of ALT, AST, and malondialdehyde (MDA), and upregulated the contents of glutathione (GSH) and cytochrome P450 (CYP450). An acute chicken liver injury model was established in vivo with 2.0 mL/kg 50% CCL4. Oral administration of SMP at different doses exhibited preventive success. The results showed that compared with the control group, the contents of total protein (TP), albumin (Alb), and GSH in the liver injury model group were significantly decreased and the levels of liver index, ALT, AST, and MDA were significantly increased. In contrast, in the SMP group the contents of TP, Alb, and GSH were significantly increased, and the levels of liver index, ALT, AST, and MDA were significantly decreased compared with the model group. Therefore, we conclude that SMPs have good protective effect on chicken liver damage in vivo and in vitro.

Evaluation of the Effects of Cultured Bone Marrow Mesenchymal Stem Cell Infusion on Hepatocarcinogenesis in Hepatocarcinogenic Mice With Liver Cirrhosis

OBJECTIVES

Liver transplantation remains the only curative therapy for decompensated liver cirrhosis. However, it has several limitations, and not all patients can receive liver transplants. Therefore, liver regenerative therapy without liver transplantation is considered necessary. In this study, we attempted minimally invasive liver regenerative therapy by peripheral vein infusion of bone marrow-derived mesenchymal stem cells (BMSCs) cultured from a small amount of autologous bone marrow fluid and evaluated the effects of BMSCs on hepatocarcinogenesis in a mouse model.

METHODS

C57BL/6 male mice were injected intraperitoneally with N-nitrosodiethylamine once at 2 weeks of age, followed by carbon tetrachloride twice a week from 6 weeks of age onwards, to create a mouse model of highly oncogenic liver cirrhosis. From 10 weeks of age, mouse isogenic green fluorescent protein-positive BMSCs (1.0 × 10⁶/body weight) were infused once every 2 weeks, for a total of 5 times, and the effects of frequent BMSC infusion on hepatocarcinogenesis were evaluated.

RESULTS

In the histologic evaluation, no significant differences were observed between the controls and BMSC-administered mice in terms of incidence rate, number, or average size of foci and tumors. However, significant suppression of fibrosis and liver injury was confirmed in the group that received BMSC infusions.

DISCUSSION

Considering that BMSC infusion did not promote carcinogenesis, even in the state of highly oncogenic liver cirrhosis, autologous BMSC infusion might be a safe and effective therapy for human decompensated liver cirrhosis.

Revealing Different Lung Metastatic Potentials Induced Metabolic Alterations of Hepatocellular Carcinoma Cells via Proton Nuclear Magnetic Resonance Spectroscopy

Background: Hepatocellular carcinoma (HCC) causes death mainly by disseminated metastasis progression and major challenge of clinical management is to distinguish lethal metastatic stage from indolent stage. It is shown that metastatic progression is closely related to cellular metabolism. But detailed metabolic alterations and molecular mechanisms still kept unclear between subtypes of different lung metastatic potentials. Methods: The current work used NMR-based metabolomics in the study of HCC cells with high malignancy but differed in lung metastatic potentials. Cell extracts and cultured media from MHCC97L and MHCC97H were utilized to reveal metabolic alterations related to metastatic potentials. Multivariate analyses were performed to identify characteristic metabolites which were used subsequently to draw the map of relative biochemical pathways by combining KEGG database. Results: The NMR spectra of both MHCC97L and MHCC97H include various signals from necessary nutritional components and metabolic intermediates. A series of characteristic metabolites were determined from both cell extracts and media. The ability on nutrient uptake varied from cell lines. Most of amino acids decreased in high metastatic cell line, so altered amino acid metabolisms and energy metabolism were revealed in high metastatic MHCC97H cell line. The majority pathways involved six essential amino acids in which the observed branched-chain amino acids together with lysine contributed to biosynthesis or degradation. Basically MHCC97H cell line could induce more active events than that of MHCC97L to progress to high metastasis with certain molecular events. Characteristic metabolites-derived classifiers performed robustly during prediction and confirmed their critical role in supporting metastasis progression. Conclusions: Our results provide evidence that NMR-metabolomics analyses of cells are able to understand metastatic characteristics accountable for biological properties. The proposed characteristic metabolites will help to understand HCC metastatic characterizations and may be filtered as potential biomarkers.

Mesenchymal Stromal Cells: Emerging Roles in Bone Metastasis

Bone metastasis is the most advanced stage of many cancers and indicates a poor prognosis for patients due to resistance to anti-tumor therapies. The establishment of metastasis within the bone is a multistep process. To ensure survival within the bone marrow, tumor cells must initially colonize a niche in which they can enter dormancy. Subsequently, reactivation permits the proliferation and growth of the tumor cells, giving rise to a macro-metastasis displayed clinically as a bone metastatic lesion. Here, we review the evidences that suggest mesenchymal stromal cells play an important role in each of these steps throughout the development of bone metastasis. Similarities between the molecular mechanisms implicated in these processes and those involved in the homeostasis of the bone indicate that the metastatic cells may exploit the homeostatic processes to their own advantage. Identifying the molecular interactions between the mesenchymal stromal cells and tumor cells that promote tumor development may offer insight into potential therapeutic targets that could be utilized to treat bone metastasis.

Utility of miR‑133a‑3p as a diagnostic indicator for hepatocellular carcinoma: An investigation combined with GEO, TCGA, meta‑analysis and bioinformatics

Increasing evidence has demonstrated that microRNA (miR)‑133a‑3p is an important regulator of hepatocellular carcinoma (HCC). In the present study, the diagnostic role of miR‑133a‑3p in HCC, and the potential functional pathways, were both explored based on publicly available data. Eligible microarray datasets were collected from NCBI Gene Expression Omnibus (GEO) database and ArrayExpress database. The data related to HCC and matched adjacent normal tissues were also downloaded from The Cancer Genome Atlas (TCGA). Published studies reporting the association between miR‑133a‑3p expression and HCC were reviewed from multiple databases. By combining the data derived from three sources (GEO, TCGA and published studies), the authors analyzed the comprehensive relationship between miR‑133a‑3p expression and clinicopathological features of HCC. Eventually, putative targets of miR‑133a‑3p in HCC were selected for further bioinformatics prediction. A total of eight published microarray datasets were gathered, and the pooled results demonstrated that the expression of miR‑133a‑3p in the tumor group was lower than that in normal groups [standardized mean difference (SMD)=‑0.54; 95% confidence interval (CI), ‑0.74 to ‑0.35; P<0.001]. Consistently, the level of miR‑133a‑1 in HCC was reduced markedly compared to normal tissues (P<0.001) based on TCGA data, and the AUC value of low miR‑133a‑1 expression for HCC diagnosis was 0.670 (P<0.001). Furthermore, the combined SMD of all datasets (GEO, TCGA and literature) suggested that significant difference was observed between the HCC group and the normal control group, and lower miR‑133a‑3p expression in HCC group was noted (SMD=‑0.69; 95% CI, ‑1.10 to ‑0.29; P=0.001). In addition, the authors discovered five key genes of the calcium signaling pathway (NOS1, ADRA1A, ADRA1B, ADRA1D and TBXA2R) that may probably be targeted by miR‑133a‑3p in HCC. The study reveals that miR‑133a‑3p may function as a tumor suppressor in HCC. The prospective novel pathways and key genes of miR‑133a‑3p could offer potential biomarkers for HCC; however, the predictions require further confirmation.

Magnetic Resonance Gd-RGD Imaging Study of Hepatocellular Carcinoma with High and Low Metastatic Potential before and after Human Bone Marrow-derived Mesenchymal Stem Cell Intervention

Background:

Biotherapy based on human bone marrow-derived mesenchymal stem cells (BMSCs) is currently the focus of research, especially in the field of autologous stem cell transplantation. A novel type of metastasis-associated magnetic resonance (MR) molecular imaging probe was constructed, and the changes in metastasis and proliferation of hepatocellular carcinoma (HCC) before and after BMSC intervention were observed through MR imaging (MRI).

Methods:

Metastasis-associated MR molecular imaging probe, integrin α_vβ₃ ligand cRGD-PEG-DGL-DTPA-Gd (Gd-RGD), were constructed. After human BMSC intervention was performed for 6 weeks, tumor weight inhibition rates were calculated, and the RGD molecular probe was imaged through MRI with molecular imaging agent Gd-DTPA as control. The signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) in the MRI experiment were used as semi-quantitative indicators. Polymerase chain reaction method was performed to detect proliferation- and metastasis-associated indicators, transforming growth factor β-1 (TGFβ1), osteopontin (OPN), and integrin subunit α_v and β₃.

Results:

The highest tumor weight inhibition rates were observed 3 weeks after the BMSC transplantation. The MR Gd-RGD in the HCC tissues after the BMSC intervention showed less enhancement than Gd-DTPA. The Gd-DTPA MRI of control group had higher SNR and CNR than Gd-RGD MRI in the experimental groups (P < 0.05). For high metastatic potential hepatocellular carcinoma (MHCC97-H), significant differences were observed in the SNRs and CNRs of Gd-RGD MRI before and after the BMSC intervention (P < 0.05). For low metastatic potential hepatocellular carcinoma (MHCC97-L), the CNRs of Gd-RGD MRI were statistically different before and after BMSC intervention (P < 0.05). With regard to MHCC97-H, OPN, β₃, and TGFβ1 expression significantly decreased after BMSC intervention (P < 0.05). In MHCC97-L and OPN, β₃, TGFβ1, and α_v expression after BMSC intervention decreased, and the difference was statistically significant (P < 0.05).

Conclusions:

The CNR index of MRI is a good indicator for distinguishing high- and low-metastatic potential HCC tissues. After BMSC transplantation of MRI through the two kinds of tracer, the SNR and CNR indexes can distinguish two kinds of high and low metastatic potential HCC tissues, and Gd-RGD imaging is more suitable in distinguishing the metastatic potential changes through BMSC intervention.

Human-derived normal mesenchymal stem/stromal cells in anticancer therapies

The tumor microenvironment (TME) not only plays a pivotal role during cancer progression and metastasis, but also has profound effects on therapeutic efficacy. Stromal cells of the TME are increasingly becoming a key consideration in the development of active anticancer therapeutics. However, dispute concerning the role of stromal cells to fight cancer continues because the use of mesenchymal stem/stromal cells (MSCs) as an anticancer agent is dependent on the specific MSCs subtype, in vitro or in vivo conditions, factors secreted by MSCs, types of cancer cell lines and interactions between MSCs, cancer cells and host immune cells. In this review, we mainly focus on the role of human-derived normal MSCs in anticancer therapies. We first discuss the use of different MSCs in the therapies for various cancers. We then focus on their anticancer mechanism and clinical application.

Involvement of TGF-β1/Smad3 Signaling in Carbon Tetrachloride-Induced Acute Liver Injury in Mice

Transforming growth factor-beta1 (TGF-β1) is a major factor in pathogenesis of chronic hepatic injury. Carbon tetrachloride (CCl4) is a liver toxicant, and CCl4-induced liver injury in mouse is a classical animal model of chemical liver injury. However, it is still unclear whether TGF-β1 is involved in the process of CCl4-induced acute chemical liver injury. The present study aimed to evaluate the role of TGF-β1 and its signaling molecule Smad3 in the acute liver injury induce by CCl4. The results showed that CCl4 induced acute liver injury in mice effectively confirmed by H&E staining of liver tissues, and levels of not only liver injury markers serum ALT and AST, but also serum TGF-β1 were elevated significantly in CCl4-treated mice, compared with the control mice treated with olive oil. Our data further revealed that TGF-β1 levels in hepatic tissue homogenate increased significantly, and type II receptor of TGF-β (TβRII) and signaling molecules Smad2, 3, mRNA expressions and Smad3 and phospho-Smad3 protein levels also increased obviously in livers of CCl4-treated mice. To clarify the effect of the elevated TGF-β1/Smad3 signaling on CCl4-induced acute liver injury, Smad3 in mouse liver was overexpressed in vivo by tail vein injection of Smad3-expressing plasmids. Upon CCl4 treatment, Smad3-overexpressing mice showed more severe liver injury identified by H&E staining of liver tissues and higher serum ALT and AST levels. Simultaneously, we found that Smad3-overexpressing mice treated with CCl4 showed more macrophages and neutrophils infiltration in liver and inflammatory cytokines IL-1β and IL-6 levels increment in serum when compared with those in control mice treated with CCl4. Moreover, the results showed that the apoptosis of hepatocytes increased significantly, and apoptosis-associated proteins Bax, cytochrome C and the cleaved caspase 3 expressions were up-regulated in CCl4-treated Smad3-overexpressing mice as well. These results suggested that TGF-β1/Smad3 signaling was activated during CCl4-induced acute liver injury in mice, and Smad3 overexpression aggravated acute liver injury by promoting inflammatory cells infiltration, inflammatory cytokines release and hepatocytes apoptosis. In conclusion, the activation of TGF-β signaling contributes to the CCl4-induced acute liver injury. Thus, TGF-β1/Smad3 may serve as a potential target for acute liver injury therapy.

A novel antagonist of CXCR4 prevents bone marrow-derived mesenchymal stem cell-mediated osteosarcoma and hepatocellular carcinoma cell migration and invasion

Recent findings suggest that bone marrow-derived mesenchymal stem cells (BM-MSCs) are recruited into the microenvironment of developing tumors, where they contribute to metastatic processes. The aim of this study was to investigate the role of BM-MSCs in promoting osteosarcoma and hepatocellular carcinoma cell progression in vitro and the possible mechanisms involved in these processes. U2OS and SNU-398 are osteosarcoma and hepatocellular carcinoma cell lines, respectively, that can be induced to proliferate when cultured in the presence of BM-MSCs. To determine the effect of BM-MSCs on U2OS and SNU-398 cells, the AKT and ERK signaling pathways were investigated, and increases were observed in active P-Akt and P-Erk forms. Moreover, BM-MSCs caused an increase in tumor cell migration and invasion that was derived from the enhancement of CXCR4 levels. Thus, when tumor cells were treated with the CXCR4 antagonist AMD3100, a reduction in their migration and invasion was observed. Furthermore, a new CXCR4 inhibitor, Peptide R, which was recently developed as an anticancer agent, was used to inhibit BM-MSC-mediated tumor invasion and to overcome AMD3100 toxicity. Taken together, these results suggest that inhibiting CXCR4 impairs the cross-talk between tumor cells and BM-MSCs, resulting in reduced metastatic potential in osteosarcoma and hepatocellular carcinoma cells.