The significance of CDT1 expression in non-cancerous and cancerous liver in cases with hepatocellular carcinoma.

We previously reported that chromatin licensing and DNA replication factor 1 (CDT1) expression was associated with the extent of proliferation of atypical hepatocytes and the time to postoperative recurrence in cases of hepatocellular carcinoma (HCC). This study aimed to clarify the clinical significance or pathogenesis of CDT1 expression in both non-cancerous and cancerous liver in HCC cases, including previously published data. We investigated the association between the expression of CDT1 in non-cancerous or cancerous liver tissues and histologic findings or biochemical examination results in 62 cases. We also examined the dual localization between CDT1 and FbxW7, P57kip2, P53 and c-Myc by confocal laser scanning microscopy. CDT1 mRNA expression was significantly higher in cancerous liver than in non-cancerous liver (p<0.0001). Elevated CDT1 mRNA expression indicates a significantly degree of inflammatory cell infiltration within lobules, along with elevated serum transaminase levels, and hepatic spare decline. CDT1 mRNA was highly expressed in a group of poorly differentiated cancer cells. CDT1 co-localized with P57kip2, Fbwx7, P53 and c-Myc in the nucleus or cytoplasm of hepatocytes and cancer cells. We found that CDT1 mRNA expression could represent the degree of hepatic spare ability and the high carcinogenic state.

EGF domain peptide of Developmentally regulated endothelial locus1 facilitates gene expression of extracellularly applied plasmid DNA.

BACKGROUND: The successful development of messenger RNA vaccines for SARS-CoV-2 opened up venues for clinical nucleotide-based vaccinations. For development of DNA vaccines, we tested whether the EGF domain peptide of Developmentally regulated endothelial locus1 (E3 peptide) enhances uptake of extracellularly applied plasmid DNA. METHODS: DNA plasmid encoding lacZ or GFP was applied with a conditioned culture medium containing E3 peptide to cell lines in vitro or mouse soleus muscles in vivo, respectively. After 48 h incubation, gene expression was examined by ß-galactosidase (ß-gal) assay and fluorescent microscope, respectively. RESULTS: Application of E3 peptide-containing medium to cultured cell lines induced intense ß-gal activity in a dose-dependent manner. Intra-gastrocnemius injection of E3 peptide-containing medium to mouse soleus muscle succeeded in the induction of GFP fluorescence in many cells around the injection site. CONCLUSIONS: The administration of E3 peptide facilitates transmembrane uptake of extracellular DNA plasmid which induces sufficient extrinsic gene expression.

Development of Capsular Fibrosis Beneath the Liver Surface in Humans and Mice.

Glisson's capsule is the connective tissue present in the portal triad as well as beneath the liver surface. Little is known about how Glisson's capsule changes its structure in capsular fibrosis (CF), which is characterized by fibrogenesis beneath the liver surface. In this study, we found that the human liver surface exhibits multilayered capsular fibroblasts and that the bile duct is present beneath the mesothelium, whereas capsular fibroblasts are scarce and no bile ducts are present beneath the mouse liver surface. Patients with cirrhosis caused by alcohol abuse or hepatitis C virus infection show development of massive CF. To examine the effect of alcohol on CF in mice, we first injected chlorhexidine gluconate (CG) intraperitoneally and then fed alcohol for 1 month. The CG injection induces CF consisting of myofibroblasts beneath the mesothelium. One month after CG injection, the fibrotic area returns to the normal structure. In contrast, additional alcohol feeding sustains the presence of myofibroblasts in CF. Cell lineage tracing revealed that mesothelial cells give rise to myofibroblasts in CF, but these myofibroblasts disappear 1 month after recovery with or without alcohol feeding. Capsular fibroblasts isolated from the mouse liver spontaneously differentiated into myofibroblasts and their differentiation was induced by transforming growth factor beta 1 (TGF-ß1) or acetaldehyde in culture. In alcohol-fed mice, infiltrating CD11b+ Ly-6CLow/- monocytes had reduced mRNA expression of matrix metalloproteinase 13 and matrix metalloproteinase 9 and increased expression of tissue inhibitor of matrix metalloproteinase 1, Tgfb1, and interleukin-10 during resolution of CF. Conclusion: The present study revealed that the structure of Glisson's capsule is different between human and mouse livers and that alcohol impairs the resolution of CF by changing the phenotype of Ly-6CLow/- monocytes.

The role of cellular interactions in the induction of hepatocyte polarity and functional maturation in stem cell-derived hepatic cells.

The unique microenvironment found within the liver in vivo plays a key role in the induction of functional maturation in the developing hepatocyte. During organogenesis, hepatocytes acquire a polar phenotype that allows them to perform their functions of bile production and transport, protein synthesis, metabolism, and detoxification simultaneously, independently, and efficiently. It is thought that the induction of polarity and functional maturation in hepatocytes is dependent on the complex interplay of cell-cell and cell-extracellular matrix (ECM) interactions. While this process is highly efficient in the human liver, it has been shown that hepatocytes rapidly lose their functions when placed in cell culture. This poses a challenge for the development of a bioartificial liver (BAL) support system, which utilizes a live cellular source to perform hepatic functions in the event of acute liver failure or primary nonfunction. However, once the molecular mechanisms underlying the induction of hepatocyte polarity are fully identified, it will be possible to develop highly functional hepatic cells from human pluripotent stem cells (hPSCs). This new cell line would be an ideal cellular source for a BAL system, as it would have both the functionality and longevity to support a patient through the entire clinical course of treatment. In this review, we explore the literature that has examined the potential mechanisms that induce polarity in the developing hepatocyte and discuss the future implications of this knowledge in a clinical setting from a bioengineering perspective.

Effects of Pyrrole-Imidazole Polyamides Targeting Human TGF-ß1 on the Malignant Phenotypes of Liver Cancer Cells.

Synthetic pyrrole-imidazole (PI) polyamides bind to the minor groove of double-helical DNA with high affinity and specificity, and inhibit the transcription of corresponding genes. In liver cancer, transforming growth factor (TGF)-ß expression is correlated with tumor grade, and high-grade liver cancer tissues express epithelial-mesenchymal transition markers. TGF-ß1 was reported to be involved in cancer development by transforming precancer cells to cancer stem cells (CSCs). This study aimed to evaluate the effects of TGF-ß1-targeting PI polyamide on the growth of liver cancer cells and CSCs and their TGF-ß1 expression. We analyzed TGF-ß1 expression level after the administration of GB1101, a PI polyamide that targets human TGF-ß1 promoter, and examined its effects on cell proliferation, invasiveness, and TGF-ß1 mRNA expression level. GB1101 treatment dose-dependently decreased TGF-ß1 mRNA levels in HepG2 and HLF cells, and inhibited HepG2 colony formation associated with downregulation of TGF-ß1 mRNA. Although GB1101 did not substantially inhibit the proliferation of HepG2 cells compared to untreated control cells, GB1101 significantly suppressed the invasion of HLF cells, which displayed high expression of CD44, a marker for CSCs. Furthermore, GB1101 significantly inhibited HLF cell sphere formation by inhibiting TGF-ß1 expression, in addition to suppressing the proliferation of HLE and HLF cells. Taken together, GB1101 reduced TGF-ß1 expression in liver cancer cells and suppressed cell invasion; therefore, GB1101 is a novel candidate drug for the treatment of liver cancer.

An Epidermal Growth Factor Motif of Developmental Endothelial Locus 1 Protein Inhibits Efficient Angiogenesis in Explanted Squamous Cell Carcinoma In Vivo.

BACKGROUND: Cancer gene therapy using a nonviral vector is expected to be repeatable, safe, and inexpensive, and to have longterm effectiveness. Gene therapy using the E3 and C1 (E3C1) domain of developmental endothelial locus-1 (Del1) has been shown to improve prognosis in a mouse transplanted tumor model. OBJECTIVE: In this study, we examined how this treatment affects angiogenesis in mouse transplanted tumors. MATERIALS AND METHODS: Mouse transplanted tumors (SCCKN human squamous carcinoma cell line) were injected locally with a nonviral plasmid vector encoding E3C1 weekly. Histochemical analysis of the transplanted tumors was then performed to assess the effects of E3C1 on prognosis. RESULTS: All mice in the control group had died or reached an endpoint within 39 days. In contrast, one of ten mice in the E3C1 group had died by day 39, and eight of ten had died or reached an endpoint by day 120 (p < 0.01). Enhanced apoptosis in tumor stroma was seen on histochemical analyses, as was inhibited tumor angiogenesis in E3C1-treated mice. In addition, western blot analysis showed decreases in active Notch and HEY1 proteins. CONCLUSION: These findings indicate that cancer gene therapy using a nonviral vector encoding E3C1 significantly improved life-span by inhibiting tumor angiogenesis.

Clinical hepatocyte transplantation.

A severe shortage of suitable allografts is a long-standing and worldwide problem for patients who are waiting for organ transplantation. Hepatocyte transplantation has been proposed as an alternative therapeutic approach for liver disease patients to address this urgent and unmet medical need. The cell replacement approach does not replace orthotopic liver transplantation (OLT), but rather it complements OLT especially for patients who do not require whole liver replacement, such as those with congenital metabolic disorders. This review article summarizes the current knowledge and limitations of clinical hepatocyte transplantation and aims to advance our understanding toward the goal of developing novel cell replacement therapies for patients who are on the OLT waiting list.

Evaluation of the mass transfer rate using computer simulation in a three-dimensional interwoven hollow fiber-type bioartificial liver.

OBJECTIVES: To determine the most efficient design of a hollow fiber-based bioreactor device for a bioartificial liver support system through comparative bioengineering evaluations. RESULTS: We compared two types of hollow fiber-based bioreactors, the interwoven-type bioreactor (IWBAL) and the dialyzer-type bioreactor (DBAL), by evaluating the overall mass transfer coefficient (K) and the convective coefficient (X). The creatinine and albumin mass transfer coefficients and convective coefficients were calculated using our mathematical model based on the homoporous theory and the modified Powell method. Additionally, using our model, we simulated the mass transport efficiency in clinical-scale BALs. The results of this experiment demonstrate that the mass transfer coefficients for creatinine and albumin increased proportionally with velocity with the IWBAL, and were consistently greater than that found with the DBAL. These differences were further enhanced in the simulation of the large-scale model. CONCLUSIONS: Our findings indicate that the IWBAL with its unique 30° cross hollow fiber design can provide greater solute removal and more efficient metabolism when compared to the conventional DBAL design.

Therapeutic potential of placenta-derived stem cells for liver diseases: current status and perspectives.

Over the last decade, there has been a growing interest in the human placenta as a unique source of stem cells. The placenta is a fetal organ that is normally discarded following delivery. Therefore, it is readily available as a source of cells without the ethical concerns normally associated with embryonic stem cells. These cells also carry less risk for age- and environmental-related DNA damage. In addition to these practical advantages of placenta-derived cells, amniotic epithelial cells possess unique stem cell-like biological characteristics. In contrast to other parts of the placenta, cells from the amniotic epithelium are derived from pluripotent epiblasts and possess the ability to differentiate into all three germ layers. From a translational perspective, amnion-derived stem cells are very attractive candidates for clinical application. These cells are genetically stable and do not demonstrate tumorigenicity upon transplantation, and may be endowed with immunomodulatory and/or anti-inflammatory properties. These unique characteristics have made amniotic epithelial cells attractive for use as stem cell-based therapies for liver disease. Human and rodent amniotic epithelial cells have already demonstrated their therapeutic efficacy in multiple animal models. Although the detailed mechanism by which the transplanted cells generate a therapeutic effect is not yet totally understood, these dramatic results have generated significant interest for consideration of these amnion-derived stem cells for clinical applications. This review covers recent findings of the therapeutic potential of amnion-derived stem cells for liver diseases, and provides perspectives for future developments.

Efficient human fetal liver cell isolation protocol based on vascular perfusion for liver cell-based therapy and case report on cell transplantation.

Although hepatic cell transplantation (CT) holds the promise of bridging patients with end-stage chronic liver failure to whole liver transplantation, suitable cell populations are under debate. In addition to hepatic cells, mesenchymal stem cells (MSCs) and hematopoietic stem cells (HSCs) are being considered as alternative cell sources for initial clinical cell work. Fetal liver (FL) tissue contains potential progenitors for all these cell lineages. Based on the collagenase incubation of tissue fragments, traditional isolation techniques yield only a fraction of the number of available cells. We report a 5-step method in which a portal vein in situ perfusion technique is used for tissue from the late second trimester. This method results in the high viabilities known for adult liver vascular perfusion, addresses the low cell yields of conventional digestion methods, and reduces the exposure of the tissue to collagenase 4-fold. We used donated tissue from gestational weeks 18 to 22, which yielded 1.8 ± 0.7 × 10(9) cells with an average viability of 78%. Because HSC transplantation and MSC transplantation are of interest for the treatment of hepatic failure, we phenotypically confirmed that in addition to hepatic progenitors, the resulting cell preparation contained cells expressing typical MSC and HSC markers. The percentage of FL cells expressing proliferation markers was 45 times greater than the percentage of adult hepatocytes expressing these markers and was comparable to the percentage of immortalized HepG2 liver hepatocellular carcinoma cells; this indicated the strong proliferative capacity of fetal cells. We report a case of human FL CT with the described liver cell population for clinical end-stage chronic liver failure. The patient's Model for End-Stage Liver Disease (MELD) score improved from 15 to 10 within the first 18 months of observation. In conclusion, this human FL cell isolation protocol may be of interest for further clinical translation work on the development of liver cell-based therapies.

Hepatic differentiation of amniotic epithelial cells.

UNLABELLED: Hepatocyte transplantation to treat liver disease is largely limited by the availability of useful cells. Human amniotic epithelial cells (hAECs) from term placenta express surface markers and gene characteristics of embryonic stem cells and have the ability to differentiate into all three germ layers, including tissues of endodermal origin (i.e., liver). Thus, hAECs could provide a source of stem cell-derived hepatocytes for transplantation. We investigated the differentiation of hAECs in vitro and after transplantation into the livers of severe combined immunodeficient (SCID)/beige mice. Moreover, we tested the ability of rat amniotic epithelial cells (rAECs) to replicate and differentiate upon transplantation into a syngenic model of liver repopulation. In vitro results indicate that the presence of extracellular matrix proteins together with a mixture of growth factors, cytokines, and hormones are required for differentiation of hAECs into hepatocyte-like cells. Differentiated hAECs expressed hepatocyte markers at levels comparable to those of fetal hepatocytes. They were able to metabolize ammonia, testosterone, and 17α-hydroxyprogesterone caproate, and expressed inducible fetal cytochromes. After transplantation into the liver of retrorsine (RS)-treated SCID/beige mice, naïve hAECs differentiated into hepatocyte-like cells that expressed mature liver genes such as cytochromes, plasma proteins, transporters, and other hepatic enzymes at levels equal to adult liver tissue. When transplanted in a syngenic animal pretreated with RS, rAECs were able to engraft and generate a progeny of cells with morphology and protein expression typical of mature hepatocytes. CONCLUSION: Amniotic epithelial cells possess the ability to differentiate into cells with characteristics of functional hepatocytes both in vitro and in vivo, thus representing a useful and noncontroversial source of cells for transplantation.

Selection of red fluorescent protein for genetic labeling of mitochondria and intercellular transfer of viable mitochondria.

The phenomenon of intercellular mitochondrial transfer has attracted great attention in various fields of research, including stem cell biology. Elucidating the mechanism of mitochondrial transfer from healthy stem cells to cells with mitochondrial dysfunction may lead to the development of novel stem cell therapies to treat mitochondrial diseases, among other advances. To visually evaluate and analyze the mitochondrial transfer process, dual fluorescent labeling systems are often used to distinguish the mitochondria of donor and recipient cells. Although enhanced green fluorescent protein (EGFP) has been well-characterized for labeling mitochondria, other colors of fluorescent protein have been less extensively evaluated in the context of mitochondrial transfer. Here, we generated different lentiviral vectors with mitochondria-targeted red fluorescent proteins (RFPs), including DsRed, mCherry (both from Discosoma sp.) Kusabira orange (mKOκ, from Verrillofungia concinna), and TurboRFP (from Entacmaea quadricolor). Among these proteins, mitochondria-targeted DsRed and its variant mCherry often generated bright aggregates in the lysosome while other proteins did not. We further validated that TurboRFP-labeled mitochondria were successfully transferred from amniotic epithelial cells, one of the candidates for donor stem cells, to mitochondria-damaged recipient cells without losing the membrane potential. Our study provides new insight into the genetic labeling of mitochondria with red fluorescent proteins, which may be utilized to analyze the mechanism of intercellular mitochondrial transfer.

Differences in the stemness characteristics and molecular markers of distinct human oral tissue neural crest-derived multilineage cells.

OBJECTIVES: Although multilineage cells derived from oral tissues, especially the dental pulp, apical papilla, periodontal ligament, and oral mucosa, have neural crest-derived stem cell (NCSC)-like properties, the differences in the characteristics of these progenitor cell compartments remain unknown. The current study aimed to elucidate these differences. MATERIAL AND METHODS: Sphere-forming apical papilla-derived cells (APDCs), periodontal ligament-derived cells (PDLDCs), and oral mucosa stroma-derived cells (OMSDCs) from the same individuals were isolated from impacted developing teeth. All sphere-forming cells were characterized through biological analyses of stem cells. RESULTS: All sphere-forming cells expressed neural crest-related markers. The expression of certain tissue-specific markers such as CD24 and CD56 (NCAM1) differed among tissue-derived cells. Surprisingly, the expression of only CD24 and CD56 could be discriminated in human tissues. Although APDCs and PDLDCs exhibited greater mineralized cell differentiation than OMSDCs, they exhibited poorer differentiation into adipocytes in vitro. In immunocompromised mice, APDCs formed hard tissues better than PDLDCs and OMSDCs. CONCLUSIONS: Although cells with NCSC-like properties present the same phenotype, they differ in the expression of certain markers and differentiation abilities. This study is the first to demonstrate the differences in the differentiation ability and molecular markers among multilineage human APDCs, PDLDCs, and OMSDCs obtained from the same patients, and to identify tissue-specific markers that distinguish tissues in the developing stage of the human tooth with immature apex.

Inhibition of Epithelial-Mesenchymal Transition Maintains Stemness in Human Amniotic Epithelial Cells.

Human amniotic epithelial cells (hAECs), which are a type of placental stem cell, express stem cell marker genes and are capable of differentiating into all three germ layers under appropriate culture conditions. hAECs are known to undergo TGF-ß-dependent epithelial-mesenchymal transition (EMT); however, the impact of EMT on the stemness or differentiation of hAECs has not yet been determined. Here, we first confirmed that hAECs undergo EMT immediately after starting primary culture. Comprehensive transcriptome analysis using RNA-seq revealed that inhibition of TGF-ß-dependent EMT maintained the expression of stemness-related genes, including NANOG and POU5F1, in hAECs. Moreover, the maintenance of stemness did not affect the nontumorigenic characteristics of hAECs. We showed for the first time that TGF-ß-dependent EMT negatively affected the stemness of hAECs, providing novel insight into cellular processes of placental stem cells.

A case of breast squamous cell carcinoma following breast augmentation with liquid silicone injection after 16 years.

BACKGROUND: Breast augmentation has been linked to various complications, including cancerous tumors. The majority type of breast cancer associated with breast augmentation is adenocarcinoma. Primary squamous cell carcinoma (SCC) of the breast is extremely rare in both augmented and non-augmented women. Due to the low incidence, the possible origin and the mechanism of carcinogenesis of the breast SCC are not well understood. Here, we report a rare case of pure SCC 16 years after breast augmentation with liquid silicone injection. CASE PRESENTATION: A 51-year-old Japanese woman was suffered from prolonged breast fluid retention in her left breast. Multiple unknown foreign bodies caused difficulties to investigate the inflammatory focus with ultrasonography. After unsuccessful surgical drainage and antibiotics treatments, the long-standing fluid retention was surgically removed and pathologically investigated. SCC was found in the removed tissue, and the patient underwent a total left mastectomy followed by postoperative chemotherapy. Pathological analysis revealed multiple cystic structures with a hard shell which enclosed high viscous liquid. A qualitative analysis using a Fourier transform infrared spectroscope defined the liquid as pure silicon, which possibly caused the squamous cell carcinogenesis. CONCLUSIONS: Although liquid silicone injection is not a current option for breast augmentation, the injected silicone could result in cancerous tumor generation after years. This case revealed that unphysiological substances could lead to unexpected biological reactions, which caused difficulties in diagnosis with our routine examination. It will be required that accumulate information from more cases and develop novel diagnostic equipment and biomarkers to address these artificial substance-derived tumors.

The proliferation of atypical hepatocytes and CDT1 expression in noncancerous tissue are associated with the postoperative recurrence of hepatocellular carcinoma.

Recently, we reported that extent of proliferation of atypical hepatocytes (atypical hepatocytes) was most important histological risk factor for development of hepatocellular carcinoma (HCC) from chronic hepatitis C or liver cirrhosis. Here, we aimed to clarify whether the atypical hepatocytes in noncancerous sections is also involved in postoperative recurrence. Furthermore, we investigated significant genes involved in the atypical hepatocytes. Association between the extent of atypical hepatocytes in noncancerous tissue and postoperative recurrence was validated in 356 patients with HCC. Next, we identified putative signature genes involved in extent of atypical hepatocytes. First, atypical hepatocytes or hepatocytes other than the atypical hepatocyte in noncancerous sections of 4 HCC patients were selectively collected by laser capture microdissection (LCM). Second, the gene expression profiles of the selected hepatocyte populations were compared using Ion AmpliSeq Transcriptome Human Gene Expression Kit (Thermo Fisher SCIENTIFIC, Waltham, MA, USA) analysis. Finally, we validated the mRNA expression of the extracted genes in noncancerous frozen liver tissue from 62 patients with HCC by RT-qPCR to identify the signature genes involved in both the extent of atypical hepatocytes and postoperative recurrence. Furthermore, the extent of atypical hepatocytes and CDT1 expression in noncancerous sections from 8 patients with HCC were also validated by selectively collecting samples using LCM. The extent of atypical hepatocytes was associated with postoperative recurrence. Of the genes that showed significant differences in expression levels between two populations, the expression of the chromatin licensing and DNA replication factor 1 (CDT1) gene was most strongly associated with the extent of atypical hepatocytes and was also associated with postoperative recurrence. Furthermore, CDT1-positive cells that exhibited stronger expression resembled those morphologically considered to be atypical hepatocytes. CDT1 and Ki-67 were colocalized in the nuclei of both hepatocytes and cancer cells. The hepatocytes in noncancerous livers were not uniform in each hepatocyte population, suggesting that the accumulation of genetic abnormalities was variable. We found that the strong degree of atypical hepatocytes and high CDT1 mRNA expression represent a high carcinogenic state of the liver. Thus, we consider the evaluation of degree of these could support the personalized medicine.

Distribution of Amniotic Epithelial Cells After Intraportal Infusion in a Rat Model.

BACKGROUND: Human amniotic epithelial cells (hAECs) are increasingly gaining attention as novel sources for cell transplantation. In clinical practice, intraportal infusion is considered one of the leading approaches for transplantation; however, this has not yet been validated for in vivo transplantation of hAECs. Thus, this study aims to investigate the distribution of hAECs post intraportal infusion and compare this distribution with other cell administration routes. METHODS: Wistar/ST rats were divided into 4 groups (n = 3 for each) based on cell administration route: group 1, intraportal; group 2, the spleen; group 3, tail veins; and group 4, penile veins. Subsequently, hAECs (1 × 107) stained with XenoLight DiR were infused into each recipient. Cell distribution was evaluated using an in vivo imaging system. RESULTS: DiR signals were detected in the rat livers of groups 1 and 2 with those in group 2 being much weaker than those in group 1. Necrosis of small intestine was observed in 2 cases in group 2. DiR signals were detected in the lungs in groups 3 and 4 because of systemic circulation; however, all the animals died within 20 minutes of infusions. CONCLUSIONS: Intraportal infusion is potentially applicable for safe and efficient transplantation of hAECs into the liver, whereas hAECs administration via the spleen carries a risk of thrombosis in a narrow portal vein system. Our results also indicate that hAECs administration via the systemic circulation could cause pulmonary embolism in clinical settings.

Human Amniotic Epithelial Cells Secretome: Components, Bioactivity, and Challenges.

Human amniotic epithelial cells (hAECs) derived from placental tissue have received significant attention as a promising tool in regenerative medicine. Several studies demonstrated their anti-inflammatory, anti-fibrotic, and tissue repair potentials. These effects were further shown to be retained in the conditioned medium of hAECs, suggesting their paracrine nature. The concept of utilizing the hAEC-secretome has thus evolved as a therapeutic cell-free option. In this article, we review the different components and constituents of hAEC-secretome and their influence as demonstrated through experimental studies in the current literature. Studies examining the effects of conditioned medium, exosomes, and micro-RNA (miRNA) derived from hAECs are included in this review. The challenges facing the application of this cell-free approach will also be discussed based on the current evidence.

Combination Cancer Therapy of a Del1 Fragment and Cisplatin Enhanced Therapeutic Efficiency In Vivo.

BACKGROUND/AIM: Combination cancer therapy is currently under investigation. This study examined the effect of cancer combination therapy using the E3 and C1 (E3C1) domains of developmental endothelial locus-1 (Del1) and cisplatin (CDDP) in murine transplanted tumors. MATERIALS AND METHODS: Mice with transplanted tumors (A431, SCCKN or SCC-4 cells) were injected intraperitoneally with CDDP and injected locally with nonviral plasmid vectors encoding E3C1. Histochemical analysis of the transplanted tumors was then performed to assess the effects on prognosis. RESULTS: The CDDP+E3C1 injected group had reduced tumor growth and longer survival compared to the CDDP injected group. In addition, cell death was observed in the tumor of the CDDP+E3C1 group.. Furthermore, angiogenesis and increased blood vessels were observed together with stromal development. CONCLUSION: The CDDP+E3C1 treatment resulted in improved survival and poor tumor stromal development in mice with transplanted tumors.

Clinical perspective on the use of human amniotic epithelial cells to treat congenital metabolic diseases with a focus on maple syrup urine disease.

Congenital metabolic diseases are a group of hereditary disorders caused by the deficiency of a single specific enzyme activity. Without appropriate therapy, affected patients suffer severe neurologic disability and eventual death. The current mainstays of management attempt to slow disease progression, but are not curative. Several of these diseases have demonstrated significant benefits from liver transplantation; however, this approach is limited by the morbidity associated with this invasive procedure and a shortage of donor organs. Therefore, there is a need to establish a new strategy for improving the quality of a life for these patients. One potential solution is regenerative therapy using hepatocytes generated from stem cells. Herein, we discuss pertinent issues necessary for clinical application of the human amniotic epithelial cell, a type of placental stem cell. Focusing on maple syrup urine disease as an example, where liver replacement is an effective therapy, we explore this approach from a clinician's perspective.