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Ferroptosis, a novel regulated cell death induced by iron-dependent lipid peroxidation, plays an important role in tumor development and drug resistance. Long noncoding RNAs (lncRNAs) are associated with various types of cancer. However, the precise roles of many lncRNAs in tumorigenesis remain elusive. Here we explored the transcriptomic profiles of lncRNAs in primary CRC tissues and corresponding paired adjacent non-tumor tissues by RNA-seq and found that LINC00239 was significantly overexpressed in colorectal cancer tissues. Abnormally high expression of LINC00239 predicts poorer survival and prognosis in colorectal cancer patients. Concurrently, we elucidated the role of LINC00239 as a tumor-promoting factor in CRC through in vitro functional studies and in vivo tumor xenograft models. Importantly, overexpression of LINC00239 decreased the anti-tumor activity of erastin and RSL3 by inhibiting ferroptosis. Collectively, these data suggest that LINC00239 plays a novel and indispensable role in ferroptosis by nucleotides 1–315 of LINC00239 to interact with the Kelch domain (Nrf2-binding site) of Keap1, inhibiting Nrf2 ubiquitination and increasing Nrf2 protein stability. Considering the recurrence and chemoresistance constitute the leading cause of death in colorectal cancer (CRC), ferroptosis induction may be a promising therapeutic strategy for CRC patients with low LINC00239 expression.

Fibrosis exists in almost all organs/tissues of the human body, plays an important role in the occurrence and development of diseases and is also a hallmark of the aging process. However, there is no effective prevention or therapeutic method for fibrogenesis. As a serine/threonine (Ser/Thr)-protein kinase, glycogen synthase kinase-3β (GSK-3β) is a vital signaling mediator that participates in a variety of biological events and can inhibit extracellular matrix (ECM) accumulation and the epithelial-mesenchymal transition (EMT) process, thereby exerting its protective role against the fibrosis of various organs/tissues, including the heart, lung, liver, and kidney. Moreover, we further present the upstream regulators and downstream effectors of the GSK-3β pathway during fibrosis and comprehensively summarize the roles of GSK-3β in the regulation of fibrosis and provide several potential targets for research. Collectively, the information reviewed here highlights recent advances vital for experimental research and clinical development, illuminating the possibility of GSK-3β as a novel therapeutic target for the management of tissue fibrosis in the future.

Background Repair pathway genes play an important role in the development of lung cancer. The study aimed to assess the correlation between single nucleotide polymorphisms (SNPs) in DNA repair gene (GTF2H1 and RAD54L2) and the risk of lung cancer. Methods Five SNPs in GTF2H1 and four SNPs in RAD54L2 in 506 patients with lung cancer and 510 age-and gender-matched healthy controls were genotyped via the Agena MassARRAY platform. The influence of GTF2H1 and RAD54L2 polymorphisms on lung cancer susceptibility was assessed using logistic regression analysis by calculating odds ratios (ORs) and their corresponding 95% confidence intervals (CIs). Results RAD54L2 rs9864693 GC genotype increased the risk of lung cancer (OR = 1.33, 95%CI: 1.01–1.77, p = 0.045). Stratified analysis found that associations of RAD54L2 rs11720298, RAD54L2 rs4687592, RAD54L2 rs9864693 and GTF2H1 rs4150667 with lung cancer risk were found in subjects aged ≤ 59 years. Precisely, a protective effect of RAD54L2 rs11720298 on the occurrence of lung cancer was observed in non-smokers and drinkers. GTF2H1 rs4150667 was associated with a decreased risk of lung cancer in subjects with BMI ≤ 24 kg/m2. RAD54L2 rs4687592 was associated with an increased risk of lung cancer in drinkers. In addition, GTF2H1 rs3802967 was associated with a reduced risk of lung squamous cell carcinoma. Conclusion Our study first revealed that RAD54L2 rs9864693 was associated with an increased risk of lung cancer in the Chinese Han population. This study may increase the understanding of the effect of RAD54L2 and GTF2H1 polymorphisms on lung cancer occurrence.

Background: Lung cancer is the leading source of cancer-caused disability-adjusted life years. Medical cost burden impacts the well-being of patients through reducing income, cutting daily expenses, curtailing leisure activities, and depleting exhausting savings. The COmprehensive Score for Financial Toxicity (COST) was created and validated by De Souza and colleagues. Our study intends to measure the financial burdens of cancer therapy and investigate the link between financial toxicity and health-related quality of life (HRQoL) in an advanced lung cancer population.Methods: Patients aged ≥ 18 years with confirmed stage III to IV lung cancer were eligible. The COST questionnaire verified by de Souza et al. was used to identify financial toxicity. Multivariable linear regression analysis with log transformation univariate analysis and Pearson correlations were used to perform the analysis.Results: The majority of the patients (90.8%, n = 138/152) had an annual income of $50,000 ($7,775). The cohort's insurance situation was as follows: 64.5% of the cohort had social insurance, 20.4% had commercial insurance, and 22.0% had both. Patients who were younger age (50–59, P < 0.001), employed but on sick leave, and had lower income reported increased levels of financial toxicity (P < 0.05). The risk factors for high financial toxicity: (i) younger age (50–59), (ii) Conclusion: Poorer psychological status and specific demographics are linked to increased financial toxicity (lower COST). Financial toxicity has a modest relationship with HRQoL and may have a clear link with HRQoL measurements.

The basic fibroblast growth factor (bFGF) plays an important role in the wound repair process. However, lacking of better biomaterials to carry bFGF still is a challenge in skin repair and regeneration. In this study, the human-like collagen (HLC) cross-linked with transglutaminase (TG) to fabricate a HLC/TG hydrogel to load bFGF. The physical properties of hydrogel, such as interior structure, mechanical property, were characterized

Forkhead box O4 (FOXO4), a member of FOXO family, has been highlighted as an essential transcriptional regulator in many diverse carcinomas. Accumulated studies have demonstrated that FOXO4 is downregulated and associated with tumorigenesis, invasiveness, and metastasis of most human cancer. FOXO4 alteration is also closely linked to the prognosis of various types of cancer. The aim of this review is to comprehensively present the clinical and pathological significance of FOXO4 in human cancer. Additionally, the potential clinical applications of future FOXO4 research are discussed. Collectively, the information reviewed here should increase the potential of FOXO4 as a therapeutic target for cancer.

A massively parallel array of monoclonal antibodies enables rapid antibody development and target discovery across species., Antibodies are essential for elucidating gene function. However, affordable technology for proteome-scale antibody generation does not exist. To address this, we developed Proteome Epitope Tag Antibody Library (PETAL) and its array. PETAL consists of 62,208 monoclonal antibodies (mAbs) against 15,199 peptides from diverse proteomes. PETAL harbors binders for a great multitude of proteins in nature due to antibody multispecificity, an intrinsic antibody feature. Distinctive combinations of 10,000 to 20,000 mAbs were found to target specific proteomes by array screening. Phenotype-specific mAb-protein pairs were found for maize and zebrafish samples. Immunofluorescence and flow cytometry mAbs for membrane proteins and chromatin immunoprecipitation–sequencing mAbs for transcription factors were identified from respective proteome-binding PETAL mAbs. Differential screening of cell surface proteomes of tumor and normal tissues identified internalizing tumor antigens for antibody-drug conjugates. By finding high-affinity mAbs at a fraction of current time and cost, PETAL enables proteome-scale antibody generation and target discovery.

DEAD (Asp-Glu-Ala-Asp) cassette helicase 21 (DDX21) is an ATP-dependent RNA helicase that is overexpressed in various malignancies. There is increasing evidence that DDX21 is involved in carcinogenesis and cancer progression by promoting cell proliferation. However, the functional role of DDX21 in gastric cancer is largely unknown. In this study, we observed that DDX21 was significantly up-regulated in gastric cancer tissues compared to paired adjacent normal tissues. The expression of DDX21 was closely related to the pathological stage of gastric cancer. In vitro and in vivo studies had shown that knockdown of DDX21 inhibited gastric cancer cell proliferation, colony formation, G1/S cell cycle transition and xenograft growth, while ectopic expression of DDX21 promoted these cell functions. Mechanically, DDX21 induced gastric cancer cell growth by up-regulating levels of Cyclin D1 and CDK2. Taken together, these results revealed a novel role for DDX21 in the proliferation of gastric cancer cells via the Cyclin D1 and CDK2 pathways. Therefore, DDX21 can be used as a therapeutic target for gastric cancer.

Forkhead box O (FOXO) family has recently been highlighted as important transcriptional regulators associated with many diverse carcinomas. Although redundant functionality between FOXO family members with cancer is known, regulatory ability of FOXO4 for tumorigenesis and tumor metastasis is still on the way. FOXO4 significantly regulates cell cycle, resists oxidative stress, and responses to hypoxia. FOXO4 alteration is closely linked to the progression of human cancer. In this review, we introduce the regulation of FOXO4 in physiological and pathological conditions. Particularly, the pathophysiological processes and molecular pathways regulated by FOXO4 in the development and progression of cancer are also summarized. Moreover, whether FOXO4 acts as a tumor-suppressor or pro-tumoral factor in tumors and the potential directions of future FOXO4 research are discussed. The information reviewed here may assist in the experimental design and increase the potential of FOXO4 as a therapeutic target for cancer.

Growth arrest-specific 6, also known as Gas6, is a human gene encoding the Gas6 protein, which was originally found to be upregulated in growth-arrested fibroblasts. Gas6 is a member of the vitamin K-dependent family of proteins expressed in many human tissues and regulates several biological processes in cells, including proliferation, survival and migration, by binding to its receptors Tyro3, Axl and Mer (TAM). In recent years, the roles of Gas6/TAM signalling in cancer cells and the tumour microenvironment have been studied, and some progress has made in targeted therapy, providing new potential directions for future investigations of cancer treatment. In this review, we introduce the Gas6 and TAM receptors and describe their involvement in different cancers and discuss the roles of Gas6 in cancer cells, the tumour microenvironment and metastasis. Finally, we introduce recent studies on Gas6/TAM targeting in cancer therapy, which will assist in the experimental design of future analyses and increase the potential use of Gas6 as a therapeutic target for cancer.

Fibrosis is a universally age-related disease that involves nearly all organs. It is typically initiated by organic injury and eventually results in organ failure. There are still few effective therapeutic strategy targets for fibrogenesis. Forkhead box proteins O1 and O3 (FOXO1/3) have been shown to have favorable inhibitory effects on fibroblast activation and subsequent extracellular matrix production and can ameliorate fibrosis levels in numerous organs, including the heart, liver, lung, and kidney; they are therefore promising targets for anti-fibrosis therapy. Moreover, we can develop appropriate strategies to make the best use of FOXO1/3's anti-fibrosis properties. The information reviewed here should be significant for understanding the roles of FOXO1/3 in fibrosis and should contribute to the design of further studies related to FOXO1/3 and the fibrotic response and shed light on a potential treatment for fibrosis.

Macrophages are a specific mononuclear cell group abundant in almost every organ of higher animals. This group is a pivotal part of the immune system and is involved in immune responses against exogenous antigen invasion. Recently, accumulating evidence has demonstrated that macrophages participate in wound repair and tissue regeneration. In this review, we will first introduce the influences of regeneration after injury in various tissues and organs among macrophage-depleted animal models. Second, the possible relationship between macrophages and reparation capacities will be discussed. Finally, we provide a general idea about the roles of macrophages in the injury- regeneration process and then discuss the current challenges and prospects of their clinical application. The information compiled here may be useful for regenerative research and may promote macrophages as a therapeutic target in regenerative medicine.

Tissue-engineered skin equivalent (TESE) is an optimized alternative for the treatment of skin defects. Designing and fabricating biomaterials with desired properties to load cells is critical for the approach. In this study, we aim to develop a novel TESE with recombinant human collagen (rHC) hydrogel and fibroblasts to improve full-thickness skin defect repair. First, the bioactive effect of rHC on fibroblast proliferation, migration and phenotype was assayed. The results showed that rHC had good biocompatibility and could stimulate fibroblasts migration and secrete various growth factors. Then, rHC was cross-linked with transglutaminase (TG) to prepare rHC hydrogel. Rheometer tests indicated that 10% rHC/TG hydrogel could reach a oscillate stress of 251 Pa and remained stable. Fibroblasts were seeded into rHC/TG hydrogel to prepare TESE. Confocal microscope and scanning electronic microscope observation showed that seeded fibroblasts survived well in the hydrogel. Finally, the therapeutic effect of the newly prepared TESE was tested in a mouse full-thickness skin defect model. The results demonstrated that TESE could significantly improve skin defect repair in vivo. Conclusively, TESE prepared from rHC and fibroblasts in this study exhibits great potential for clinical application in the future.

The sex-determining region Y-box 7 (Sox7) is an important member of the SOX F family, which is characterized by a high-mobility-group DNA-binding domain. Previous studies have demonstrated the role of SOX7 in cardiovascular development. SOX7 expression could be detected in normal adult tissues. Furthermore, the expression levels of SOX7 were different in different tumors. Most studies showed the downregulation of SOX7 in tumors, while some studies reported its upregulation in tumors. In this review, we first summarized the upstream regulators (including transcription factors, microRNAs (miRNAs), long noncoding RNAs (lncRNAs) and some exogenous regulators) and downstream molecules (including factors in the Wnt/β-catenin signaling pathway and some other signaling pathways) of SOX7. Then, the roles of SOX7 in multiple tumors were presented. Finally, the significance of divergent SOX7 expression during cardiovascular development was briefly discussed. The information compiled in this study characterized SOX7 during tumorigenesis and cardiovascular development, which should facilitate the design of future research and promote SOX7 as a therapeutic target.

Background Safe and effective hemostatic materials are important for reducing mortality resulting from excessive hemorrhage. In this work, new biomaterials with hemostatic effects were created by fusing the gene coding for RADA-16, a self-assembling peptide with the sequence RADARADARADARADA, to the 3′-end of the open reading frame (ORF) encoding elastin-like polypeptides through gene recombination. Results The fusion proteins, termed 36R, 60R and 96R, were solubly over-expressed in Escherichia coli BL21 (DE3) based on genetic manipulation of the high-efficiency prokaryotic expression vector pET28a (+) and bacterial transformation. Western Blot analysis showed that the over-expressed proteins were the target fusion proteins. The target proteins 36R with 94.72% purity, 60R with 96.91% purity and 96R with 96.37% purity were prepared using an inverse phase transition cycle at 65 °C followed by His-tag affinity chromatography. The proliferation results of the mouse fibroblast cell line L929 and hippocampus neuron cell line HT22 indicated that the fusion proteins did not cause obvious cell toxicity. The lyophilized spongy film of the purified 36R, 60R and 96R could stop the hemorrhage of a 2 × 2 mm bleeding wound in the mouse liver after 27.21 ± 1.92 s, 18.65 ± 1.97 s and 15.85 ± 1.21 s, respectively. The hemostasis time was 21.23 ± 1.84 s for rat-tail collagen and 14.44 ± 1.33 s for RADA-16 lyophilized on gauze. The hemostatic time of three treated groups were all significantly superior to that of the negative control without any hemostasis treatment, which spontaneously stopped bleeding after 37.64 ± 1.34 s. Statistical analysis showed that the spongy film with purified 96R exhibited an exciting hemostatic effect that was superior to rat-tail collagen and close to that of RADA-16 lyophilized on gauze. Conclusions These results revealed that the fusion proteins achieved by gene recombination technology could serve as a promising hemostatic material. Electronic supplementary material The online version of this article (10.1186/s12896-018-0422-5) contains supplementary material, which is available to authorized users.

The understanding of adipose tissue development is crucial for the treatment of obesity-related diseases. Adipogenesis has been extensively investigated at the gene and protein levels in recent years. However, the alterations in protein glycosylation during this process remains unknown, particularly that of parthenogenetic embryonic stem cells (pESCs), a type of ESCs with low immunogenicity and no ethical concerns regarding their use. Protein glycosylation markedly affects cell growth and development, cell-to-cell communication, tumour growth and metastasis. In the present study, the adipogenic potentials of J1 ESCs and pESCs were first compared and the results demonstrated that pESCs had lower adipogenic potential compared with J1 ESCs. Lectin microarray was then used to screen the alteration of protein glycosylation during adipogenesis. The results revealed that protein modification of GlcNAc and α-1-2-fucosylation increased, whereas α-1-6-fucosylation, α-2-6-sialylation and α-1-6-mannosylation decreased in J1 ESCs and pESCs during this process. In addition, α-1-3-mannosylation decreased only in pESCs. Lectin histochemistry and quantitative polymerase chain reaction of glycosyltransferase confirmed the results obtained by lectin microarray. Therefore, protein glycosylation of ESCs was significantly altered during adipogenesis, indicating that protein glycosylation analysis is not only helpful for studying the mechanism of adipogenesis, but may also be used as a marker to monitor adipogenic development.

Claudin-5 is a tight junction (TJ) protein in the blood-brain barrier (BBB) that has recently attracted increased attention. Numerous studies have demonstrated that claudin-5 regulates the integrity and permeability of the BBB. Increased claudin-5 expression plays a neuroprotective role in neurological diseases, particularly in cerebral ischemic stroke. Moreover, claudin-5 might be a potential marker for early hemorrhagic transformation detection in ischemic stroke. In light of the distinctive effects of claudin-5 on the nervous system, we present the elaborate network of roles that claudin-5 plays in ischemic stroke. In this review, we first introduce basic knowledge regarding the BBB and the claudin family, the characterization and regulation of claudin-5, and association between claudin-5 and other TJ proteins. Subsequently, we describe BBB dysfunction and neuron-specific drivers of pathogenesis of ischemic stroke, including inflammatory disequilibrium and oxidative stress. Furthermore, we summarize promising ischemic stroke treatments that target the BBB via claudin-5, including modified rt-PA therapy, pharmacotherapy, hormone treatment, receptor-targeted therapy, gene therapy, and physical therapy. This review highlights recent advances and provides a comprehensive summary of claudin-5 in the regulation of the BBB and may be helpful for drug design and clinical therapy for treatment of ischemic stroke.

The epithelial-mesenchymal transition (EMT) is an acknowledged cellular transition process in which epithelial cells acquire mesenchymal-like properties that endow cancer cells with increased migratory and invasive behavior. Forkhead box O (FOXO) proteins have been shown to orchestrate multiple EMT-associated pathways and EMT-related transcription factors (EMT-TFs), thereby modulating the EMT process. The focus of the current review is to evaluate the latest research progress regarding the roles of FOXO proteins in cancer EMT. First, a brief overview of the EMT process in cancer and a general background on the FOXO family are provided. Next, we present the interactions between FOXO proteins and multiple EMT-associated pathways during malignancy development. Finally, we propose several novel potential directions for future research. Collectively, the information compiled herein should serve as a comprehensive repository of information on this topic and should aid in the design of additional studies and the future development of FOXO proteins as therapeutic targets.

Background Gastric cancer (GC), the second leading cause of cancer mortality behind lung cancer worldwide, is caused by both genetic and environmental factors. In this study, we evaluated the association between the genetic polymorphisms of methylenetetrahydrofolate reductase (MTHFR), methionine synthesis reductase (MTR), and methyltransferase reductase (MTRR) genes and ischemic stroke risk in Chinese population. Methods A case–control study was conducted including 681 patients with GC and 756 healthy controls. Chi‐squared test/Fisher's exact test and genetic model were used to evaluate associations. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated using unconditional logistic regression. Results In the allele model, using the chi‐square test, we found that the rs1532268 in MTRR with a minor allele T was significantly associated with increased risk of GC (OR = 1.24, 95% CI, 1.00–1.53; p = 0.048). In the genetic model analysis, we identified that the single‐nucleotide polymorphism of the rs1801133 in MTHFR could increase the GC risk in the recessive model (OR = 1.31, 95% CI, 1.01–1.70; p = 0.042) and log‐additive model (OR = 1.19, 95% CI, 1.02–1.38; p = 0.025). In MTHFR, a strong linkage of rs2274976 and rs1801133 was detected. The haplotype “GC” in the MTHFR gene was found to prominently increase the risk of GC (OR = 1.26, 95% CI: 1.07–1.47; p = 0.005). Other haplotypes did not display the correlativity. Conclusion This study suggested that MTR and MTHFR polymorphisms may contribute to increase the risk of GC.

CD306, also known as soluble leukocyte-associated immunoglobulin-like receptor-2 (LAIR-2), is a member of an immunoglobulin superfamily with the shared characteristic of an immunoglobulin-like C2-type domain. CD306 is speculated to be secretory and has 84% similarity with the extracellular domain of CD305, which binds to the same ligands as CD306. However, data on its distribution are absent due to the lack of an efficient method to detect it. In this study, we successfully cloned the cDNA of CD306 from the peripheral blood mononuclear cells (PBMCs) of patients with hemorrhagic fever with renal syndrome. The fusion proteins were expressed and purified, and three strains of monoclonal antibodies (mAbs) against CD306 were prepared and characterized. The sandwich ELISA for detecting CD306 was established and optimized with sensitivity up to 15 pg/ml, and the assay showed high specificity for the detection of CD306. With this method, a right skewed frequency distribution of CD306 in the sera of healthy subjects was determined. The concentrations of CD306 in sera and urine were detected in patients with different diseases. Aberrantly high levels of CD306 were found in the sera of pregnant women and patients with inflammation and rheumatic heart disease and in the urine of pregnant women. Meanwhile, there was a positive correlation between CD306 and soluble CD305 expression and secretion levels in sera and urine samples from patients, and both proteins inhibited CD305-mediated immunosuppressive functions. Our results demonstrate that CD306 represents a potentially useful predictor for disease diagnosis and that the method developed has potential for clinical application.

With the increasing occurrence of vascular diseases and poor long-term patency rates of current small diameter vascular grafts, it becomes urgent to pursuit biomaterial as scaffold to mimic blood vessel morphologically and mechanically. In this study, novel human-like collagen (HLC, produced by recombinant E. coli)/chitosan tubular scaffolds were fabricated by cross-linking and freeze-drying process. The scaffolds were characterized by scanning electron microscope (SEM), X-ray photoelectron spectroscopy (XPS), and tensile test, respectively. Human venous fibroblasts were expanded and seeded onto the scaffolds in the density of 1 x 10(5) cells/cm(2). After a 15-day culture under static conditions, the cell-polymer constructs were observed using SEM, confocal laser scanning microscopy (CLSM), histological examination, and biochemical assays for cell proliferation and extracellular matrix production (collagen and glycosaminoglycans). Furthermore, the scaffolds were implanted into rabbits' livers to evaluate their biocompatibility. The results indicated that HLC/chitosan tubular scaffolds (1) exhibited interconnected porous structure; (2) achieved the desirable levels of pliability (elastic up to 30% strain) and stress of 300 +/- 16 kPa; (3) were capable of enhancing cell adhesion and proliferation and ECM secretion; (4) showed superior biocompatibility. This study suggested the feasibility of HLC/chitosan composite as a promising candidate scaffold for blood vessel tissue engineering.

Despite of progresses in tissue engineering based on cell/scaffold strategy, uneven cell distribution as well as tissue formation in the scaffold, limited cell seeding efficiency and inflammatory reaction triggered by the degradation of scaffold remain problems to be resolved. In this study, we proposed a novel cell-macroaggregate cultivation system, and explored a feasible strategy to construct three-dimensional cartilage tissue with shape of human nasal alar by using cell macroaggregate. Isolated chondrocytes was cultured at high density to form a monolayer chondrocyte sheet as well as expanded for seeding on the sheet to produce mechanically operable cell macroaggregate. Chondrocyte macroaggregates were then fabricated into transplants with shape of nasal alar by using Internal support or External scaffold techniques; results of in vivo chondrogenesis were investigated in immunocompetent animal. Chondrocyte macroaggregates presented long survival time and good viability; constructs fabricated using both techniques can develop into tissues with characteristic structure of native cartilage, glycosaminoglycans as well as type II collagen were highly produced in the ECM of engineered cartilages. By placing hyaluronan ester film as Internal support, the predetermined shape of the chondrocyte macroaggregate can be well maintained. In contrast, due to the poor mechanical stability of grafts fabricated in External scaffold group, obvious deformation occurred in harvested specimens. The experiment proved the usefulness of chondrocyte macroaggregate in cartilage regeneration, and provided a new strategy to engineer cartilage with special shape by using cell macroaggregate/biodegradable support.

Tissue engineered bone has become a bone substitute for the treatment of bone defects in animal research. This study investigated the osteogenesis capacity of coral-MSCs-rhBMP-2 composite with the auto-bone-graft as control. Coral-MSCs-rhBMP-2 composite were fabricated by coral (as main scaffold), rhBMP-2 (as growth factor), and MSCs (cultured from iliac marrow as seed cells). Critical-sized defects (d = 15 mm) were made on forty rabbits crania and treated by different composite scaffolds: iliac autograft (n = 8), coral (n = 8), rhBMP-2/coral (n = 8), and MSCs/rhBMP-2/coral (n = 8). The defects were evaluated by gross observation, radiographic examination, histological examination, and histological fluorescence examinations after 8 and 16 weeks. The results showed that repair of bone defect was the least in coral group, and significant ingrowth of new bone formation and incorporation could be seen with 77.45% +/- 0.52% in radiopacity in MSCs/rhBMP-2/coral group, which was similar to that in iliac autograft group (84.61% +/- 0.56% in radiopacity). New bone formation in MSCs/rhBMP-2/coral group was more than that in rhBMP-2/coral group. And osteogenesis rate in MSCs/rhBMP-2/coral group (10.23 +/- 1.45 microm) was much faster than that in rhBMP-2/coral group (5.85 +/- 2.19 microm) according to histological fluorescence examination. Newly formed bone partly came from induced MSCs in composite scaffold according to bromodeoxyuridine immunohistochemical examination. These data implicated that MSCs could produce synergic effect with coral-rhBMP-2, and the tissue engineered bone of coral-MSCs-rhBMP-2 is comparable to auto-bone-graft for the repair of critical-sized bone defect.

Skin grafts, including skin flaps, are widely used in plastic and reconstructive surgery to cover wounds and tissue defects resulting from mechanic or burn injury. Ischemic necrosis is the main complication in skin graft surgery due to inefficient revascularization. Though the surgical delay procedure has been proved to be the only effective technique to prevent skin flap ischemic necrosis by mechanism of inducing adaption to hypoxia, but it is time consuming, costly, and having high risk of infection due to repeated surgery. Recent research demonstrated that, in addition to protecting cells against apoptosis, the expression of survivin correlates with intratumoral microvessel density in several different types of tumors and survivin could upregulate several proangiogenic factors, including VEGF, Egr-1 and Siah-1. Moreover, Survivin DeltaEx3, one of the survivin alternative splice variants, is necessary for activating the small GTPase Rac1 during endothelial tube formation and required for in vivo endothelial cell invasion. Therefore, we postulate that intracellular delivery of survivin or Survivin DeltaEx3 by fusion with protein transduction domain would enhance skin flap survival through accelerating revascularization by both inhibiting the apoptosis of microvascular endothelial cells and promoting skin flap angiogenesis. If the hypothesis was proved to be practical, the fusion proteins would be widely used in plastic and reconstructive surgery to prevent skin flap from ischemic necrosis in the future.

Purpose: The purpose of this study was to develop a tissue-engineered bone graft model in the shape of a human mandibular condyle. Materials and Methods: Natural coral with a pore size of 150 to 220 μm and porosity of about 36% was molded into the shape of a human mandibular condyle. Culture-expanded rabbit marrow mesenchymal stem cells were induced by recombinant human bone morphogenetic protein-2 (rhBMP2) to improve osteoblastic phenotype. Then marrow-derived osteoblasts were seeded into natural coral at a density of 2 × 108/mL and incubated in vitro for 3 days before implantation. The cell–coral complexes were implanted subcutaneously into the backs of nude mice and incubated in vivo for 2 months before harvesting. Implantation of coral alone acted as control. The specimens were processed for gross inspection, radiographic examination, and histologic and scanning electronic microscopic observation. Results: The results showed that new bone grafts in the shape of a human mandibular condyle were successfully developed 2 months after implantation and maintained the initial shape of the natural coral scaffold. New bone could be observed histologically on the surface and in the pores of natural coral in all specimens in the cell-seeding group (6 of 6), whereas in the control group there was no evidence of osteogenesis process (0 of 4). Conclusion: This study suggests the feasibility of using porous coral as scaffold material transplanted with marrow-derived osteoblasts to restore bone graft in the shape of human mandibular condyle and shows the potential of using this method for the reconstruction of bone defects. © 2002 American Association of Oral and Maxillofacial Surgeons J Oral Maxillofac Surg 60:1155-1159, 2002

In 20 male Sprague-Dawley rats, 10 pieces of L-shaped coral combined with type I collagen and recombinant human bone morphogenetic protein-2 (rhBMP-2) and 10 discs (diameter 5 mm) were wrapped in the gracilis muscle, and left pedicled on the femoral vessels. Untreated coral was buried in muscle at a distant control site in 4 animals. After 3 weeks, autografts were examined for the shape of new bone, vascular patency, and induction of bone. In all grafts in viable tissue, heterotopic bone was formed. The shape of the new bone was the same as that of the coral, and there was no significant inflammatory reaction. Part of the coral in the composite was absorbed. Bone was not formed in any of the control sites. Coral and type 1 collagen are effective as a carrier for BMP to prefabricate vascular osteomuscular autografts with designed shape. There is a potential clinical application for BMP to bioengineer microvascular free flaps with intrinsic skeletal muscle for maxillofacial reconstruction.

Hypoxia is a common phenomenon in human solid tumors and has been considered as an important, independent negative prognostic factor for response to treatment and survival of tumor patients. Hypoxia-inducible factor-1 (HIF-1) is the central transcription factor which is activated by hypoxia and modulates the expression of many genes involved in cell metabolism, proliferation, apoptosis, angiogenesis. Recently, it has been reported that HIF-1 contributes to tumor radioresistance by upregulating survivin expression under hypoxic conditions. Moreover, in hypoxic tumor cells, HIF-1 dependent signal transduction pathway is activated and could be further enhanced by radiation, thereby providing survival signals to adjacent vascular endothelial cells by upregulation of VEGF and bFGF and resulting in tumor radioresistance through vascular radioprotection. Recent research revealed that the stability of HIF-1alpha, one of the two subunits of HIF-1, determines the whole HIF-1 activity and the C-terminal transactivation domain of HIF-1alpha could reduce HIF-1 activity when overexpressed in tumor cells by disruption of the assembly of HIF-1 transcription complex. Therefore, we postulate that fusion with protein transduction domains would overcome the inability of C-terminal transactivation domain of HIF-1alpha to cross cellular membrane. Thus the recombinant fusion proteins could serve as cell-permeable HIF-1 antagonists, function as both inhibitors of tumor angiogenesis and tumor radiosensitizers, and would be widely used in clinical settings to improve tumor response to radiotherapy.

A higher degree of mineralization is found within scaffold groups implanted with cells compared to scaffold alone demonstrating greater bone regenerative potential of cell-scaffold constructs Tissue engineered bone analysed using ESEM and SAXS demonstrates bone formation within the scaffold to be preferentially aligned around the scaffold struts. The mineral particles are not shown to orientate around the osteons within the native bone.

Colon cancer is a type of malignant tumor that causes considerable mortality worldwide. Epithelial cellular adhesion molecule (EpCAM), a tumor-associated antigen of colon tumors, is a target for colon cancer therapy. EpCAM-specific monoclonal antibodies (mAbs) have been applied in human colon cancer since the 1990s; however, the therapeutic effects are limited. EpCAM activates nuclear signaling pathways by releasing its intracellular domain (EpICD). The released EpICD stimulates the Wnt/β-catenin signaling pathway, which is also strongly associated with tumorigenesis. EpCAM is also a target gene of the Wnt/β-catenin signaling pathway. EpCAM and the Wnt/β-catenin signaling pathway form a functional interaction cycle in colon cancer. Thus, we propose a new therapeutic drug for colon cancer: an EpCAM single-chain fragment variable antibody (scFv)-truncated protamine-siRNA. EpCAM scFv can recognize and bind colon cancer cells through its EpCAM antigen activity. Furthermore, the specific siRNA transferred into colon cancer cells specifically inhibits Wnt/β-catenin signal transmission. Therefore, this new drug may efficiently interrupt the functional cycle between EpCAM and Wnt/β-catenin signaling and be an effective therapeutic strategy for colon cancer.

In recent years, a large number of researchers have paid much attention on small interfering RNA (siRNA) after the advent of RNA interference technology, which has been harnessed as an efficient way of sequence-specific gene silencing in gene therapy, enables elucidation of gene functions, and the identification of new drug targets. Despite tremendous progress has been made in novel delivery systems and vectors via formulation of polyplexes and conjugations, such as cationic polymers (LPEI, BPEI), cationic liposome (DOTAP), peptides (CPP), unmet needs still exist. Many cationic agents used for condensing siRNA often exhibits severe cytotoxicity, which limits clinical applications, and is obliged to be handled. Thus great interest in searching for novel and sophisticated polymeric vectors has been spurred. Herein we proposed a genetically synthetic protein-based polymer, which is also referred to as elastin-like polypeptides (ELPs) excerpted from human tropoelastin highly repetitive sequence, Val-Pro-Gly-Xaa-Gly, where the "guest residue" Xaa is any amino acid except Pro. Thus, if we alternate the "guest residue" Xaa to Lys or Arg, to a significant extent, it can emerge as a powerful cationic polymer for siRNA delivery carrier, and hopefully it will be put into practice in the near future.

Due to the limited regenerative capacity of cartilage tissues, articular cartilage defect caused by various lesions remains a problem to be resolved. Tissue engineering provided a valuable alternative to current therapeutic approaches, which is expected to greatly reduce the need of joint replacement. Scaffold, acting as cell carrier, plays an important role in maintaining cells in defect sites, thus facilitates the chondrogenesis. However, an open operation is often needed to implant the cell/scaffold composite, to find a less invasive way to delivering the complex into the defect site would be desirable. Different from synthetic and other nature derived scaffold, platelet-rich plasma (PRP) is a fraction of plasma which contains multiple growth factors and could be clotted when mixed with thrombin. Therefore, we hypothesized that PRP could be used as an autologous cell carrier to inject and fix chondrocytes into the defect site of articular cartilage. With the assistance of arthroscope, the defect could be precisely located, and injectable PRP-Cell composite would make the operation micro-invasive and simple.

The affected individual of hair loss demands help, because hair is viewed as a sign of youth and good health. Nowadays treatment of alopecia includes drug therapy and hair transplantation. Some drugs may promote hair growth, at least temporarily, but the treatment is effective only in milder alopecia, instead of extensive alopecia. Furthermore, the side effect of long period medication could not be avoided. Hair transplantation involves harvesting small pieces of hair-bearing scalp grafts from a donor site and relocating them to a bald area. This method does not increase the number of existing hairs, but only redistributes them. The operation is sophisticated and time-consuming, thus the patient suffers a lot during the process. The discovery of hair follicle stem cells (FSC) brings gospel to the affected individual of hair loss because of its capacity of generating new hair when they interact with mesenchymal dermal papilla cells (DPC). Besides, both FSC and DPC have strong proliferative capacity and the patient's own cells could be expanded considerably in vitro. Thus we hypothesize that the microencapsulation of the two kinds of cells in alginate gels could be implanted into the bald scalp of the patient since alginate gels is effective in cell transplantation. The strategy may provide a more convenient and valid alternative to hair loss if the hypothesis proved to be practical.

To evaluate repair of critical-sized cranial defect with tissue engineered bone fabricated by coral, bone mesenchymal stem cells (MSCs) and sustainedly released recombinant human bone morphogenetic protein 2 (rhBMP-2) by collagen.Three scaffolds of rhBMP-2 + coral, collagen + rhBMP-2 + coral and MSCs+collagen+rhBMP-2+coral were fabricated. Forty New Zealand rabbits were made the models of critical-sized defects and divided into 5 groups according to different implants: group I, auto-ilium; group II, coral; group III, rhBMP-2+coral; group IV, collagen+rhBMP-2+coral; and group V , MSCs+collagen+rhBMP-2+coral. Repair of bone defect was evaluated after 8 and 16 weeks of implantation by gross observation, X-ray, HE staining and Masson's trichrome staining.Repair of bone defect in group V was similar to that in group I, and was better than that in group IV; and group III was worse. The gross appearance showed that defect region filled with bony tissue which had similar strength to adjacent bone and formed bone union with surrounding bone. The X-ray result displayed high radiopacity (80.45% +/- 2.52% in the 16th week). Histological observation showed new lamellar bone tissue and with few pore blank area. However, only transparent fibrous tissue filled the defect in group II.Collagen may be a suitable sustained release system for rhBMP-2. And MSCs may have important effect on enhancing repair of bone defect. Tissue engineered bone fabricated by MSCs+collagen+rhBMP-2+coral may be a useful material for bone defect repair.

To find out if it was possible to prefabricate bone graft in the shape of a human mandibular ramus that possessed a pedicle that carried blood. The pore size of the natural coral was about 200 microm with a porosity of about 36%. The natural coral was made into the shape of a human mandibular ramus. Marrow-derived osteoblasts were seeded into porous natural coral scaffolds in a density of 2 x 10(8)/mL in 300 microL cell suspension. After two days of in vitro incubation, five cell-coral complexes were implanted into cell donor rabbits under the inferior epigastric blood vessels to prefabricate a vascularised bone graft of specific shape. Two months later the bone formation was observed by gross inspection and histological examination. Two months after operation, a well-vascularised bone graft in the shape of the initial coral scaffold and with a blood-carrying pedicle had been regenerated successfully. Osteogenesis followed the pattern of endochondral bone formation. New bone could be seen on the surface and in the pores of coral on histological examination. We have shown that it is possible to fabricate vascularised bone graft in a predetermined shape using tissue engineering. This kind of bone graft may have future clinical application.