FOXF2 oppositely regulates stemness in luminal and basal-like breast cancer cells through the Wnt/beta-catenin pathway.

The stemness of cancer cells contributes to tumorigenesis, the heterogeneity of malignancies, cancer metastasis, and therapeutic resistance. However, the roles and regulatory mechanisms maintaining stemness among breast cancer subtypes remain elusive. Our previous studies have demonstrated that ectopic expression and dynamic alteration of the mesenchymal transcription factor forkhead box F2 (FOXF2) differentially regulates breast cancer progression and metastasis organotropism in a cell subtype-specific manner. Here, we reveal the underlying mechanism by which FOXF2 enhances stemness in luminal breast cancer cells but suppresses that in basal-like breast cancer (BLBC) cells. We show that luminal breast cancer and BLBC cells with FOXF2-regulated stemness exhibit partial mesenchymal stem cell properties that toward osteogenic differentiation and myogenic differentiation, respectively. Furthermore, we show that FOXF2 activates the Wnt signaling pathway in luminal breast cancer cells but represses this pathway in BLBC cells by recruiting nuclear receptor coactivator 3 (NCoA3) and nuclear receptor corepressor 1 (NCoR1) to the promoters of Wnt family member 2B (WNT2B) and frizzled class receptor 1 (FZD1) genes to activate and repress their transcription, respectively. We propose that targeting the Wnt signaling pathway is a promising strategy for the treatment of breast cancers with dysregulated expression of FOXF2.

A composite single-nucleotide polymorphism prediction signature for extranodal natural killer/T-cell lymphoma.

Current prognostic scoring systems based on clinicopathologic variables are inadequate in predicting the survival and treatment response of extranodal natural killer/T-cell lymphoma (ENKTL) patients undergoing nonanthracyline-based treatment. We aimed to construct a classifier based on single-nucleotide polymorphisms (SNPs) for improving predictive accuracy and guiding clinical decision making. Data from 722 patients with ENKTL from international centers were analyzed. A 7-SNP-based classifier was constructed using LASSO Cox regression in the training cohort (n = 336) and further validated in the internal testing cohort (n = 144) and in 2 external validation cohorts (n = 142 and n = 100). The 7-SNP-based classifier showed good prognostic predictive efficacy in the training cohort and the 3 validation cohorts. Patients with high- and low-risk scores calculated by the classifier exhibited significantly different progression-free survival (PFS) and overall survival (OS) (all P < .001). The 7-SNP-based classifier was further proved to be an independent prognostic factor by multivariate analysis, and its predictive accuracy was significantly better than clinicopathological risk variables. Application of the 7-SNP-based classifier was not affected by sample types. Notably, chemotherapy combined with radiotherapy significantly improved PFS and OS vs radiotherapy alone in high-risk Ann Arbor stage I patients, whereas there was no statistical difference between the 2 therapeutic modalities among low-risk patients. A nomogram was constructed comprising the classifier and clinicopathological variables; it showed remarkably better predictive accuracy than either variable alone. The 7-SNP-based classifier is a complement to existing risk-stratification systems in ENKTL, which could have significant implications for clinical decision making for patients with ENKTL.

A case report of syndrome of inappropriate antidiuretic hormone secretion with Castleman's disease and lymphoma.

BACKGROUND: Syndrome of inappropriate antidiuretic hormone secretion (SIADH) is a common cause of hyponatremia in hospitalized patients and is often described in patients with small-cell carcinoma of the lung. In this report, we described both Castleman's disease and lymphoma coexisting in one patient with SIADH. CASE PRESENTATION: A 70-year-old Chinese woman with a history of diabetes mellitus and insulin therapy had severe hyponatremia and gastrointestinal symptoms. Through a series of examinations, common causes such as pulmonary carcinoma were excluded. An abdominal mass was detected by computed tomography. Although the peripheral lymph node biopsy showed the pathological result as Castleman's disease, the pathology of the abdominal lymph node revealed diffuse large B-cell lymphoma. After chemotherapy, the hyponatremia was treated during a period of follow-up. CONCLUSION: This patient presented with the rare clinical condition of inappropriate antidiuretic hormone secretion alongside Castleman's disease and lymphoma. Asymptomatic hyponatremia may persist for some time suggesting that clinical physicians should pay attention to the mild cases of hyponatremia. We also hypothesized that Castleman's disease is a condition of pre-lymphoma with both having the ability to cause SIADH. The possibility of lymphoma as well as Castleman's disease triggering the development of SIADH should also be taken into consideration for conducting recurrent biopsies.

[Clinical features and outcome analyses of newly-diagnosed multiple myeloma with extramedullary involvements].

OBJECTIVE: To explore the clinical features and prognostic factors of newly-diagnosed multiple myeloma (MM) with extramedullary (EM) involvements. METHODS: The clinical features, efficacies, survival rates and prognostic factors were retrospectively analyzed in 46 MM patients with EM (group A) from January 2000 to October 2011. And another 53 MM patients without EM (group B) were selected as the controls. RESULTS: The median age of Group A was 58 years. Compared with group B, the incidence of EM was associated with a higher level of ß2-microglobulin (ß2-MG) and extensive bone disease. The most common location of EM was soft tissues. And the total effective rates of groups A and B were 58.5% (24/41) and 78.8% (41/52) respectively. The difference was statistically significant (P = 0.042). The median follow-up time was 28(2-88) months. The estimated overall survival (OS) of the patients with EM was significantly shorter than those without EM (42.6 vs 53.9 months, P = 0.009). Log-rank univariate analysis showed that the number of osteolytic lesions ≥ 3, ß2-MG ≥ 5.5 mg/L, hemoglobin ≤ 110 g/L and albumin ≤ 30 g/L were poor prognostic factors in MM patients with EM. Multivariate analysis with Cox model showed only the number of osteolytic lesions ≥ 3 (OR = 2.327, 95%CI: 1.282 - 4.224) and ß2-MG ≥ 5.5 mg/L (OR = 2.677, 95%CI: 1.092 - 6.566) were statistically significant. CONCLUSIONS: Multiple EM lesions may be involved in MM patients. For the patients with EM, the response to conventional chemotherapy is poor and the prognosis is unfavorable, especially for those with a high level of ß2-MG or the number of osteolytic lesions ≥ 3.

Analysis of albumin as a prognostic factor in HHV-8/HIV-negative Castleman disease from a multicenter study.

As a rare lymphoproliferative disorder, many patients with HHV-8/HIV-negative Castleman disease (CD) have hypoalbuminemia. However, data is limited on whether hypoalbuminemia is an independent predictor of CD. We retrospectively collected data from 230 patients diagnosed at 12 medical centers in China and the U.S. Different classifications included 147 patients with unicentric CD (UCD) and 83 with idiopathic multicentric CD (iMCD). Adjusted smooth curve fitting showed that the relationship between albumin and all-cause death of patients with CD and iMCD was linear. Cox proportional hazards regression modeling showed a negative association between the risk of death and albumin level (hazard ratio [HR]: 0.84; 95% CI, 0.76, 0.93). Using the Kaplan-Meier method, we determined that hypoproteinemia was a risk factor for poorer prognosis in patients with CD, UCD, and iMCD. Albumin was independently and negatively associated with the risk of death in CD patients, especially those with iMCD.

A CpG Methylation Classifier to Predict Relapse in Adults with T-Cell Lymphoblastic Lymphoma.

PURPOSE: Adults with T-cell lymphoblastic lymphoma (T-LBL) generally benefit from treatment with acute lymphoblastic leukemia (ALL)-like regimens, but approximately 40% will relapse after such treatment. We evaluated the value of CpG methylation in predicting relapse for adults with T-LBL treated with ALL-like regimens. EXPERIMENTAL DESIGN: A total of 549 adults with T-LBL from 27 medical centers were included in the analysis. Using the Illumina Methylation 850K Beadchip, 44 relapse-related CpGs were identified from 49 T-LBL samples by two algorithms: least absolute shrinkage and selector operation (LASSO) and support vector machine-recursive feature elimination (SVM-RFE). We built a four-CpG classifier using LASSO Cox regression based on association between the methylation level of CpGs and relapse-free survival in the training cohort (n = 160). The four-CpG classifier was validated in the internal testing cohort (n = 68) and independent validation cohort (n = 321). RESULTS: The four-CpG-based classifier discriminated patients with T-LBL at high risk of relapse in the training cohort from those at low risk (P < 0.001). This classifier also showed good predictive value in the internal testing cohort (P < 0.001) and the independent validation cohort (P < 0.001). A nomogram incorporating five independent prognostic factors including the CpG-based classifier, lactate dehydrogenase levels, Eastern Cooperative Oncology Group performance status, central nervous system involvement, and NOTCH1/FBXW7 status showed a significantly higher predictive accuracy than each single variable. Stratification into different subgroups by the nomogram helped identify the subset of patients who most benefited from more intensive chemotherapy and/or sequential hematopoietic stem cell transplantation. CONCLUSIONS: Our four-CpG-based classifier could predict disease relapse in patients with T-LBL, and could be used to guide treatment decision.

A gene-expression-based signature predicts survival in adults with T-cell lymphoblastic lymphoma: a multicenter study.

We aimed to establish a discriminative gene-expression-based classifier to predict survival outcomes of T-cell lymphoblastic lymphoma (T-LBL) patients. After exploring global gene-expression profiles of progressive (n = 22) vs. progression-free (n = 28) T-LBL patients, 43 differentially expressed mRNAs were identified. Then an eleven-gene-based classifier was established using LASSO Cox regression based on NanoString quantification. In the training cohort (n = 169), high-risk patients stratified using the classifier had significantly lower progression-free survival (PFS: hazards ratio 4.123, 95% CI 2.565-6.628; p < 0.001), disease-free survival (DFS: HR 3.148, 95% CI 1.857-5.339; p < 0.001), and overall survival (OS: HR 3.790, 95% CI 2.237-6.423; p < 0.001) compared with low-risk patients. The prognostic accuracy of the classifier was validated in the internal testing (n = 84) and independent validation cohorts (n = 360). A prognostic nomogram consisting of five independent variables including the classifier, lactate dehydrogenase levels, ECOG-PS, central nervous system involvement, and NOTCH1/FBXW7 status showed significantly greater prognostic accuracy than each single variable alone. The addition of a five-miRNA-based signature further enhanced the accuracy of this nomogram. Furthermore, patients with a nomogram score ≥154.2 significantly benefited from the BFM protocol. In conclusion, our nomogram comprising the 11-gene-based classifier may make contributions to individual prognosis prediction and treatment decision-making.

FOXF2 reprograms breast cancer cells into bone metastasis seeds.

Bone metastases occur in most advanced breast cancer patients and cause serious skeletal-related complications. The mechanisms by which bone metastasis seeds develop in primary tumors and specifically colonize the bone remain to be elucidated. Here, we show that forkhead box F2 (FOXF2) functions as a master transcription factor for reprogramming cancer cells into an osteomimetic phenotype by pleiotropic transactivation of the BMP4/SMAD1 signaling pathway and bone-related genes that are expressed at early stages of bone differentiation. The epithelial-to-osteomimicry transition regulated by FOXF2 confers a tendency on cancer cells to metastasize to bone which leads to osteolytic bone lesions. The BMP antagonist Noggin significantly inhibits FOXF2-driven osteolytic bone metastasis of breast cancer cells. Thus, targeting the FOXF2-BMP/SMAD axis might be a promising therapeutic strategy to manage bone metastasis. The role of FOXF2 in transactivating bone-related genes implies a biological function of FOXF2 in regulating bone development and remodeling.

Prognostic and predictive value of a microRNA signature in adults with T-cell lymphoblastic lymphoma.

New prognostic factors are needed to establish indications for haematopoietic stem cell transplantation (HSCT) in first complete remission (CR1) for T-cell lymphoblastic lymphoma (T-LBL) patients. We used microarray to compare T-LBL tissue samples (n = 75) and fetal thymus tissues (n = 20), and identified 35 differentially expressed miRNAs. Using 107 subjects as the training group, we developed a five-miRNA-based classifier to predict patient survival with LASSO Cox regression: lower risk was associated with better prognosis (disease-free survival (DFS): hazard ratio (HR) 4.548, 95% CI 2.433-8.499, p < 0.001; overall survival (OS): HR 5.030, 95% CI 2.407-10.513, p < 0.001). This classifier displayed good performance in the internal testing set (n = 106) and the independent external set (n = 304). High risk was associated with more favorable response to HSCT (DFS: HR 1.675, 95% CI 1.127-2.488, p = 0.011; OS: HR 1.602, 95% CI 1.055-2.433, p = 0.027). When combined with ECOG-PS and/or NOTCH1/FBXW7 status, this classifier had even better prognostic performance in patients receiving HSCT (DFS: HR 2.088, 95% CI 1.290-3.379, p = 0.003; OS: HR 1.996, 95% CI 1.203-3.311, p = 0.007). The five-miRNA classifier may be a useful prognostic biomarker for T-LBL adults, and could identify subjects who could benefit from HSCT.

Occurrence of lymphoma in non-gonadal organ during pregnancy: a report on four cases and literature review.

Lymphoma rarely occurs during pregnancy, making this condition difficult to define. Lymphomas that occur in reproductive organs during pregnancy exhibit unique clinical characteristics. Among the limited cases, non-Hodgkin's lymphoma (NHL) shows a considerably higher incidence rate than Hodgkin's lymphoma (HL); NHL also displays clinical characteristics, such as high aggressiveness, advanced stage, and poor outcome. This study reports on four cases of lymphomas in non-gonadal organs (HL, n=2; NHL, n=2) during pregnancy. The tumors rapidly progressed in all patients during pregnancy but remitted at the end of pregnancy and/or therapy. The two HL cases were nodular sclerosis classical HL and treated with chemotherapy after terminating the pregnancy. One of the NHL cases was primary cutaneous follicular center lymphoma, a B cell-derived indolent lymphoma. The patient was followed up without any therapy after terminating her pregnancy. The other case was a follicular lymphoma grade 3B, which was treated with chemotherapy after delivery. We also conducted a literature review of 165 lymphoma cases occurring during pregnancy reported from 1976 to 2013 to reveal the correlation between pregnancy and lymphoma progression. Immunohistochemistry studies were performed to determine the expression of estrogen/progesterone receptors (ER/PR), and ER was weakly positive and sporadic. We concluded that lymphomas occurring during pregnancy should be managed with a prompt and reasonable treatment. High estrogen level in maternal body may affect lymphoma progression.

Clinical significance and prognostic value of Vav1 expression in Non-small cell lung cancer.

Vav1 has been reported to be involved in human cancers, however, the expression and clinical significance of Vav1 in NSCLC are not fully understood. In the present study, we examined the expression of Vav1 in 170 NSCLC patients who underwent radical resection by the immunohistochemical analyses. The association between the Vav1 expression and clinicopathological variables was analyzed. The multivariate Cox proportional hazards model was conducted to determine the prognostic value of Vav1 on the long-term survival. The results showed that the elevated Vav1 expression was correlated positively with lymph node metastasis (P<0.001), T stage (P<0.001) and poor histological differentiation (P<0.001). Patients with negative or low Vav1 expression had better prognoses than those with high Vav1 expression (P<0.001). Multivariate analysis indicated that Vav1 was independent prognostic factor for overall survival (OS) (HR 2.079, 95% CI 1.564 to 2.762, P<0.001) and disease-free survival (DFS) (HR 1.810, 95% CI 1.391 to 2.356, P<0.001). Our findings showed that overexpressed Vav1 was correlated with aggressive tumor behavior. Val1 was an independent factor for NSCLC prognosis, which may serve as a novel prognostic factor and potential target to improve the long-term outcome of NSCLC.

[Analysis of Clinicopathological Characteristics and Prognosis of 112 Patients with Primary Waldeyer's Ring Lymphoma].

OBJECTIVE: To investigate the clinical and pathological characteristics of patients with primary Waldeyer's ring lymphomas (PWRL), and to analyze its therapeutic efficacy and prognostic factors. METHODS: A total of 112 patients with PWRL confirmed by pathological and immunohistochemical methods between January 2009 and January 2014 were studied. Clinical data were collected and analyzed retrospectively. RESULTS: PWRL accounted for 3.9% of lymphoma over the same period. Median age of patients with PWRL was 51.5 years old. The affected areas were tonsil, nasopharynx, tongue base and oropharynx, which accounted for 63.4% (71/112), 22.3% (25/112), 5.3% (6/112) and 4.5% (5/112) respectively. The most common pathological types of these four areas were diffused large B-cell lymphoma (DLBCL) and extranodal NK/T cell lymphoma (NKTCL) which accounted for 58% and 15.2%. The overall response rate (CR/CRu = 51.4%; PR = 30.8%) in all patients was 82.2%, the estimated 5-year overall survival (OS) rate were 71.6%. The 5-year OS rate were 94.7% in the group used Rituximab. Meanwhile, chemotherapy combined with radiotherapy could improve the outcome of T-cell PWRL patients and the 5-year OS rate were 88.9%. Age, disease stages, pathological types, IPI scores, LDH level, ß2-MG level and the efficacy of initial therapy were prognostic factors with statistical significance. Cox multivariate analysis showed that age of more than 60 years, LDH level, pathological types and the efficacy of the initial therapy were independently associated with OS. CONCLUSION: PWRL has a relatively good prognosis. The pathological types affect the prognosis directly and guide treatment. Combined modality therapy should be chosen for patients with PWRL. Patients with T-cell PWRL should accept chemotherapy combined with radiotherapy, while rituximab may be better for B-cell PWRL. The efficacy of initial therapy is crucial for the outcome of patients. Age and LDH level are also important prognostic factors.

Short-term ex vivo expansion sustains the homing-related properties of umbilical cord blood hematopoietic stem and progenitor cells.

BACKGROUND AND OBJECTIVES: The homing of stem cells to the bone marrow microenvironment following transplantation is a specific movement eventually leading to the stem cells lodging in specialized niches of hematopoiesis. The present study was designed to develop an ex vivo expansion system capable of preserving the homing potential of hematopoietic stem/progenitor cells (HSPC). DESIGN AND METHODS: Umbilical cord blood (UCB) CD34+ cells were expanded in QBSF-60 serum-free medium with a simple early-acting combination of cytokines and were re-selected from the expanded products at different time points. The homing-related characteristics and expansion rate of CD34+ cells were simultaneously examined. RESULTS: It was observed that the number of HSPC increased significantly under our expansion protocol. The expression of CD49d, CD44, CD11a and CD49e on expanded CD34+ cells increased or remained at the same levels as those on freshly isolated CD34+ UCB cells, while the expression of CD54 on expanded CD34+ cells was lower during the second week of culture than at the start. The spontaneous and SDF-1-induced adhesion of CD34+ cells was increased during the first 10 days of culture, with the adhesion rates reaching peak levels (62.8 12.8% and 90.5 11.7% for spontaneous and induced adhesion, respectively) on day 10. Neither spontaneous nor SDF-1-induced migration had changed significantly by day 7. INTERPRETATION AND CONCLUSIONS: These data demonstrate that, although ex vivo expansion may alter cell properties, our one-week expansion protocol can preserve most of the homing-related characteristics and activities of UCB HSPC.

[The effects of the short-term ex vivo expansion on the adhesion characteristics and chemotactic function of expanded ex vivo CD34(+) cells].

OBJECTIVE: To study the effect of ex vivo expansion on the adhesion activities and chemotactic function of umbilical cord blood (UCB) hematopoietic stem and progenitor cells (HSPCs). METHODS: CD34(+) cells isolated from fresh UCB samples were cultured in serum-free and stroma-free culture system. After 7, 10 and 14 days' culture, CD34(+) cells were re-selected from the expanded products. Stromal cell- derived factor-1 (SDF-1) 100 ng/ml was added into the experimental CD34(+) cells and the absorbance at 570 nm of all groups was examined. 20 micro g/ml fibronectin (Fn) was added and the spontaneous adhesion between CD34(+) and FN was detected by MTT method. The homing-related functions including expression of homing-related adhesion molecules (CAM), adhesion activity and chemotactic function of the re-selected CD34(+) cells were evaluated and compared with those of the initial fresh CD34(+) cells. RESULTS: (1) The expression of CD49d, CD44, CD11a and CD49e on expanded CD34(+) cells increased or sustained the same levels as those of the fresh isolated UCB CD34(+) cells, while the expression of CD62L, CD54 and CD31 on expanded CD34(+) cells declined during the culture. (2) The spontaneous adhesion between CD34(+) and FN and SDF-1-induced adhesion continuously increased in the course of the first 10-day culture. The spontaneous adhesion rate and SDF-1-induced adhesion rate on day 0, day 7 and day 10 were 28% and 63%, 60% and 70%, 63% and 90% respectively. (3) The migration efficiency of re-selected CD34(+) cells on day 7 was almost the same compared to that of fresh CD34(+) cells. CONCLUSION: The expanded HSPCs sustain most of the homing-related characteristics and activities during one-week culture while extended culture may partly impair their intrinsic homing potential.

[The effects of cytokines mediated ex vivo expansion on the cell adhesion molecule expression of cord blood hematopoietic stem and progenitor cells].

OBJECTIVE: To compare the expression of cell adhesion molecules (CAMs) among VLA-4 (CD49 d), VLA-5 (CD49e), LFA-1 (CD11a), L-selectin (CD62L), and PECAM-1 (CD31) which are more related to the homing of hematopoietic stem and progenitor cells (HSPC) on the ex vivo expanded CD34+ subset with that of fresh isolated AC133+ cells. METHODS: AC133+ cells selected from fresh cord blood (CB) samples were cultured in QBSF-60 serum-free media in the presence of Flt-3 ligand + SCF + TPO (FST), with initial addition of IL-3 for up to 2 week. Expansion potential and the expression of above CAMs were evaluated at day 0, day 7, day 10 and day 14. RESULTS: (1) Simultaneously numerical expansion of various HSPC was constantly observed during the culture, and the fold expansion of AC133+ cells and CD34+ cells on day 14 were 33.50 and 64.56 respectively; (2) The number of CD34+ subsets expressing the above adhesions were all increased at different degrees (from 20 fold to 160 fold). (3) The expressions of CD11a, CD49d, and CD49e on ex vivo expanded CD34+ cells were increased as compared to their baseline levels, but the percentage of CD62L+ and CD31+ subpopulations in CD34+ cells were decreased. CONCLUSIONS: Our short-term culture system can not merely support the simultaneous expansion of CB derived AC133+ cells, but the expanded hematopoietic progenitors may well sustained the expression of homing-related adhesion molecules.

[Prognostic factors of nasal NK/T-cell lymphoma].

OBJECTIVE: To investigate the prognostic predictors of nasal NK/T cell lymphoma. METHODS: Records of 80 patients with nasal NK/T cell lymphoma were analyzed retrospectively. The correlation between clinical and haematological factors and prognosis was analyzed with univariate and multivariate analysis. RESULTS: After treatment, 33 of 80 patients achieved complete response, the 5-year overall survival and progression free survival were 52.5% and 32.5%, respectively. In univariate analysis, Eastern Cooperative Oncology Group performance status, Ann Arbor stage, local tumor invasion out of the nasal cavity, international prognostic index, complete response rate to the primary treatment, treatment model, lactate dehydrogenase (LDH),ß2-microglobulin level, globulin and white blood cell were found to be the prognostic factors. Multivariate analysis indicated that unfavorable prognostic factors included complete response rate to the primary treatment (χ(2) = 17.109, P < 0.01), LDH(χ(2) = 15.695, P < 0.01), and local tumor invasion out of the nasal cavity (χ(2) = 13.503, P < 0.01). CONCLUSION: Complete response rate to the primary treatment, elevated plasma LDH and tumor invasion out of the nasal cavity may be independent prognostic factors for NK/T cell lymphoma.

[Changes of the migration ability of the cord blood CD(34)(+) cells during short-term ex vivo expansion].

OBJECTIVE: To study the effect of ex vivo expansion on the migration ability and the CXCR4 expression of umbilical cord blood (CB) hematopoietic stem/progenitor cells (HSPC). METHODS: CD(34)(+) cells isolated from fresh CB samples were cultured in a serum-free and stroma-free culture system. On day 7, 10 and 14, CD(34)(+) cells were re-selected from the expanded cells, and the expression of CXCR4 and the transmigration ability of these CD(34)(+) cells were evaluated respectively and compared with those of the precultured fresh CD(34)(+) cells. RESULTS: (1) SDF-1 induced a higher migration percentage of fresh or expanded CB CD(34)(+) cells than that of uninduced ones. (2) Both of the uninduced and SDF-1-induced migrations were slightly reduced in the first week and then much more reduced in the second week expansion (P < 0.05). (3) The number of the CD(34)(+)CXCR4(+) cells were significantly increased during the culture period, but there was a downtrend of CXCR4 expression on CD(34)(+) subset; the expression levels on day 10 and 14 were lower than that on day 0. CONCLUSIONS: The expanded HSPC would sustain the chemotactic activity during one-week-culture, but with further extended culture time their intrinsic homing potential would be partly impaired.

[Effect of platelet factor 4 on the adherence of cord blood CD34(+) cells].

OBJECTIVE: To investigate the effects of platelet factor 4 (PF4) on the adherence, and the expressions of adherent molecules CD(49d) and CXCR4 and the receptor of SDF-1 of fresh and expanded cord blood CD(34)(+) cells. METHODS: CD(34)(+) cells were isolated from cord blood using MACS immune magnetic beads. The adherent ability was assayed by using crystal violet staining and the expression of adherent molecule CD(49d) and CXCR4 by FACS. RESULTS: (1) PF4 could increase the adherent ability of the fresh cord blood CD(34)(+) cells, the effect being positively correlated with the dose of PF4. (2) SDF-1 at concentration of 100 ng/ml increased the adherent ability of the fresh cord blood CD(34)(+) cells. (3) The spontaneous and the SDF-1 induced adherent ability of the cord blood CD(34)(+) cells began to decrease after being cultured for 10 days without PF4, while in the presence of PF4 at 100 ng/ml, the ability of the cord blood CD(34)(+) cell adhering to the stroma layer still remained at higher level. At day 14, the adherent ability was (262.04 +/- 64.81)% and (64.35 +/- 8.29)% in PF4 group and control group, respectively, if it was defined as 100% at day 0. SDF-1 at concentration of 100 ng/ml induced adherent ability was (138.31 +/- 32.39)% and (67.66 +/- 12.44)% in PF4 group and control group, respectively. (4) The expression of CD(49d) and CXCR4 increased 13.02% and 17.33%, respectively, when incubated with PF4. CONCLUSIONS: PF4 could increase the adherent ability and promote the expression of CD(49d) and CXCR4 of the cord blood CD(34)(+) cells, suggesting that PF4 promote the circulating stem cells homing to the marrow in the process of stem cells transplantation.

[Studies on the homing-related adhesion activities of UCB HSPC in short-term ex vivo expansion].

OBJECTIVE: To study the effect of ex vivo expansion on the adhesion activities of umbilical cord blood hematopoietic stem and progenitor cells (HSPC). METHODS: Fresh UCB CD(34)(+) cells were cultured in a serum and stroma-free culture system. At day 7, day 10 and day 14, CD(34)(+) cells were re-selected from the expanded products. The expression of adhesion molecules (CAMs) such as VLA-4, VLA-5, LFA-1, ICAM-1, HCAM, L-selectin and PECAM-1, and the adhesion activity of the expanded CD(34)(+) cells were evaluated and compared with those of precultured fresh CD(34)(+) cells. RESULTS: (1) The CD(34)(+) cells expressing homing-related CAMs were increased (from 15-fold increase for CD(34)(+) CD(54)(+) subset to 72-fold increase for CD(34)(+) CD(49e)(+) subset at day 14). (2) The expressions of CD(49d), CD(44), CD(11a) and CD(49e) on the expanded CD(34)(+) cells were increased or sustained the same levels as those on fresh UCB CD(34)(+) cells, while the expression of CD(62L), CD(54) and CD(31) on expanded CD(34)(+) cells declined with the cultivating. (3) Spontaneous adhesion and SDF-1-induced adhesion tended to be increased in the course of the first 10 day's culture. CONCLUSIONS: The culture system used in this study could substantially support the expansion of HSPCs expressing the above CAMs, and the expanded HSPCs would sustain their intrinsic adhesion potentials.