The osteogenc potential of bone marrow has been proved by experiment. To investigate more in details, bone marrow was obtained from the trochanteric region of femur of NewZealand rabbit in 4 to 8 weeks old. After being cultured in vitro for one week, the hematopoietic component of the bone marrow had disappeared, thus the stromal cells were obtained. Then the stromal cells were subcultured in cultural fluid containing dexamethasone (10-8 mol/L) and natrium glycerophosphate (10mmol/L). Under the phasecontrast microscope, it was found that being cultured for 15 days. The stromal cells were lined up in one layer and late the secretion activity was increased and gradually transformed into multilayer structure and was congregated into diffused opaque clusters in twenty days. During culture, the cells were examined by tetracycline fluorescence label, histochemistry stains, transmission electron microscopy, scanning electron microscopy and energy dispersive X-ray microanalysis. The results showed that the morphological and biological characteristics of the cultured stromal cells derived from the bone marrow were similiar to those of osteoblasts and could synthesized mineralized new bone tissue in vitro.
ObjectiveTo summarize the therapeutic targets of pancreatic cancer (PC). MethodsThe related literatures about the therapeutic targets of PC were reviewed. ResultsPC was one of the most challenging tumor in worldwide, and was characterized as a highly aggressive disease with poor overall prognosis and a high mortality rate. The hallmark of PC was its poor response to radio-and chemo-therapy. Current chemotherapeutic regimens could not provide substantial survival benefit with a clear increase in overall survival. Recently, several new approaches which could significantly improve the clinical outcome of PC had been described, involving signal-transduction pathways, immune response, stroma reaction, and epigenetic changes. ConclusionsMany therapeutic targets are involved in the treatment of PC. As current therapies failed to significantly improve the progression and the survival of PC, new therapeutic approaches and clinical studies are strongly required.
Objective To investigate the influence on matrix metalloproteinases (MMP) 3, 9, and 13 levels of human articular cartilage cells after blocking stromal cell derived factor 1 (SDF-1)/ chemokine receptor 4 (CXCR4) signaling pathway withAMD3100 and to define the function mechanism of AMD3100. Methods A total of 144 cartilage blocks from 12 osteoarthritis (OA) patients undergoing total knee arthroplasty (OA cartilage group) and 144 normal cartilage blocks (Mankin score of 0 or 1) from 12 patients undergoing traumatic amputation (normal cartilage group). OA cartilage group was further divided into subgroups A1, B1, and C1, and normal cartilage group into subgroups A2, B2, and C2. The cartilage tissues were cultured in DMEM solution containing 100 ng/mL SDF-1 and 1 000 nmol/L AMD3100 in subgroup A, 100 ng/mL SDF-1 and 1 000 nmol/L MAB310 in subgroup B, and 100 ng/mL SDF-1 in subgroup C, respectively. The levels of MMP-3, 9, and 13 were measured by ELISA; the expressions of MMP-3, 9, and 13mRNA were tested by RT-PCR. Results ELISA and RT-PCR results showed that the levels of MMP-3, 9, and 13 and the expressions of MMP-3, 9, and 13 mRNA were significantly lower in subgroup A than in subgroups B and C at the same time points (P lt; 0.05); the levels of MMP-3, 9, and 13 and the expressions of MMP-3, 9, and 13 mRNA were significantly higher in OA cartilage group than in normal cartilage group at the same time points (P lt; 0.05). Conclusion SDF-1 could induce overexpression and release of MMP-3, 9, and 13 in the articular cartilage through the SDF-1/CXCR4 signaling pathway; AMD3100 could reduce the mRNA expressions and secretion of MMP-3, 9, and 13 in OA cartilage by blocking the SDF-1/CXCR4 signaling pathway; but AMD3100 could not make the secretion of MMP-3, 9, and 13 return to normal levels in OA cartilage.
Objective To find a kind of simple and effective method for purifying and label ing stromal vascular fraction cells (SVFs) so as to provide a theoretical basis for cl inical application of SVFs. Methods The subcutaneous adi pose tissue were harvested form volunteers. The adi pose tissue was digested with 0.065%, 0.125%, and 0.185% type I collagenase,respectively. SVFs were harvested after digestion and counted. After trypan blue staining, the rate of viable cells was observed. SVFs was labeled by 1, 1’-dioctadecyl-3, 3, 3’, 3’-2-tetramethy-lindocyanine perchlorate (DiI). The fluorescent label ing and growth was observed under an inverted fluorescence microscope. MTT assay was used to detect cell proliferation. Results The number of SVFs was (138.68 ± 11.64) × 104, (183.80 ± 10.16) × 104, and (293.07 ± 8.31) × 104 in 0.065% group, 0.125% group, and 0.185% group, respectively, showing significant differences among 3 groups (P lt; 0.01). The rates of viable cells were 91% ± 2%, 90% ± 2%, and 81% ± 2% in 0.065% group, 0.125% group, and 0.185% group, respectively, and it was significantly higher in 0.065% group and 0.125% group than in 0.185% group (P lt; 0.01), but no significant difference was found between 0.065% group and 0.125% group (P=0.881). Inverted fluorescence microscope showed that the cell membranes could be labeled by DiI with intact cell membrane, abundant cytoplasm, and good shape, but nucleus could not labeled. SVFs labeled by DiI could be cultured successfully and maintained a normal form. MTT assay showed that similar curves of the cell growth were observed before and after DiI labeled to SVFs. Conclusion The optimal collagenase concentration for purifying SVFs is 0.125%. DiI is a kind of ideal fluorescent dye for SVFs.
Objective To review research progress of adipose tissuederived stromal cells (ADSCs).Methods The recent articles on ADSCs were extensively reviewed, and the culture and differentiation ability of ADSCs were investigated.Results A population of stem cells could be isolated from adult adipose tissue, they were processed to obtain a fibroblast-like population of cells and could be maintained in vitro for extended periods with stable population doubling. The majority of the isolated cells were mesenchymal origin, with a few pericytes,endothelial cells and smooth muscle cells. ADSCs could be induced to differentiate intomultiple mesenchymal cell types, including osteogenic, chondrogenic, myogenic and adipogenic cells, they could also differentiate into nerve cells.Conclusion ADSCs can substitute mesenchymal stem cells and become an alternative stem cells source for tissue engineering.
Objective To introduce types and differentiation potentials of stem cells from adipose tissue, and its applications on regenerative medicine and advantages. Methods The literature of original experimental study and clinical research about bone marrow mesenchymal stem cells (BMSCs), adipose-derived stem cells (ADSCs), and dedifferentiated fat (DFAT) cells was extensively reviewed and analyzed. Results ADSCs can be isolated from stromal vascular fraction. As ADSCs have multi-lineage potentials, such as adipogenesis, osteogenesis, chondrogenesis, angiogenesis, myogenesis, and neurogenesis, they have already been successfully used in regenerative medicine areas. Dramatically, mature fat cells can be dedifferentiated and changed into fibroblast-like cells, named DFAT cells, via ceiling culture method. DFAT cells also had the same multi-lineage potentials as ADSCs, differentiating into adipocytes, osteocytes, chondrocytes, endothelial cells, muscle cells, and nerve cells. Compared with BMSCs which are commonly used as adult stem cells, ADSCs and DFAT cells have extensive sources and can be easily acquired. While compared with ADSCs, DFAT cells have good homogeneity and b proliferation capacity. Conclusion As a potential source of stem cells, adipose tissue will provide a new promising for regenerative medicine.
ObjectiveTo observe the effect of stromal vascular fraction cells (SVFs) from rat fat tissue combined with sustained release of recombinant human bone morphogenetic protein-2 (rhBMP-2) in promoting the lumbar fusion in rat model.MethodsSVFs were harvested from subcutaneous fat of bilateral inguinal region of 4-month-old rat through the collagenase I digestion. The sustained release carrier was prepared via covalent bond of the rhBMP-2 and β-tricalcium phosphate (β-TCP) by the biominetic apatite coating process. The sustained release effect was measured by BCA method. Thirty-two rats were selected to establish the posterolateral lumbar fusion model and were divided into 4 groups, 8 rats each group. The decalcified bone matrix (DBX) scaffold+PBS, DBX scaffold+rhBMP-2/β-TCP sustained release carrier, DBX scaffold+SVFs, and DBX scaffold+rhBMP-2/β-TCP sustained release carrier+SVFs were implanted in groups A, B, C, and D respectively. X-ray films, manual spine palpation, and high-resolution micro-CT were used to evaluate spinal fusion at 8 weeks after operation; bone mineral density (BMD) and bone volume fraction were analyzed; the new bone formation was evaluated by HE staining and Masson’s trichrome staining, osteocalcin (OCN) was detected by immunohistochemical staining.ResultsThe cumulative release amount of rhBMP-2 was about 40% at 2 weeks, indicating sustained release effect of rhBMP-2; while the control group was almost released within 2 weeks. At 8 weeks, the combination of manual spine palpation, X-ray, and micro-CT evaluation showed that group D had the strongest bone formation (100%, 8/8), followed by group B (75%, 6/8), group C (37.5%, 3/8), and group A (12.5%, 1/8). Micro-CT analysis showed BMD and bone volume fraction were significantly higher in group D than groups A, B, and C (P<0.05), and in group B than groups A and C (P<0.05). HE staining, Masson’s trichrome staining, and immunohistochemistry staining for OCN staining exhibited a large number of cartilage cells with bone matrix deposition, and an active osteogenic process similar to the mineralization of long bones in group D. The bone formation of group B was weaker than that of group D, and there was no effective new bone formation in groups A and C.ConclusionThe combination of sustained release of rhBMP-2 and freshly SVFs can significantly promote spinal fusion in rat model, providing a theoretical basis for further clinical applications.
Objective To investigate the feature of c-kit gene mutation in gastrointestinal stromal tumor (GIST) and its correlation with clinicolpathology, molecular targeted therapy,and prognosis. Methods The related literatures about the molecular genetic mechanism of GIST were reviewed. Results The c-kit gene mutation, which is prevalent in GIST, may be the early genomic events, and they are not the independent prognostic factor. However, different molecular subtype as a new indicator to regulate biological behaviors and assess prognosis of GIST is still controversial. Conclusions The study of genotype in GIST has advanced our understanding of pathogenesis, evaluating the prognosis and conducting treatment optimization. However, subsequent work remains to be done.
ObjectiveTo summarize the research status and biological characteristics of stromal fibroblast in breast cancer. MethodsRelevant literatures about the breast cancer stromal fibroblasts published recently were collected and reviewed. ResultsIn addition to cancer cells, breast cancer included stromal cells. The fibroblasts were the major components of breast cancer stromal, which had significantly different biological characteristics from normal fibroblasts. The fibroblasts were characterized by α-SMA positive, p53 gene mutation, secretion of various cytokines or chemokines in addition to the production of collagen substances, involving in breast cancer growth, migration, invasion and metastasis through a variety of signaling pathways. ConclusionThe biological characteristics of stromal fibroblasts in breast cancer may reflect lesion properties, be of great importance to diagnosis and differential diagnosis and prognosis prediction of breast cancer. More attentions will be paid to the target therapy for stromal fibroblasts in breast cancer.
ObjectiveTo explore the methods of separation, culture, and identification of breast cancer stromal fibroblasts (BCSFs), which could build up a good basis for the further research of function. MethodsBreast cancer tissues were obtained during breast cancer operation, and were cut into pieces with size of 1 mm×1 mm×1 mm under aseptic conditions, then the pieces of the tissues were digested by collagenase Ⅰ and hyaluronidase. Finally the cells separated from the tissues incubated at 37 ℃ with 5% CO2 and 95% air humidified incubator. Morphological characteristics of the fibroblasts were observed under light microscope. The certain proteins were examined by immunohistochemistry (using CK, Vimentin, α-SMA, and TE-7 antibody) and flow cytometric analysis (CD34 and CD45). ResultsThe separated cells begin to attach to the wall of flask within 24 h and reached almost confluency in about 7 d to 10 d . According to identification, the successful rate of separation and culture of BCSFs was 90%(18/20), and the characteristics of cells showed that morphological characteristics of the fibroblasts was flat spindle, rich cytoplasm, and a flat ovoid cystic nuclear. The fibroblasts in breast cancer tissues showed negative staining for cytokeratin, positive staining for vimentin, alpha-smooth muscle actin, and TE-7, and negative for CD34 and CD45 by flow cytometric analysis. ConclusionsThe fibroblasts in breast cancer tissues could be easily obtained by tissues cuting combined enzyme digestion and rocking technology in vitro. The present study provide an experimental foundation for further studies on fibroblasts in breast cancer.