Gene profile identifies zinc transporters differentially expressed in normal human organs and human pancreatic cancer

Deregulated expression of zinc transporters was linked to several cancers. However, the detailed expression profile of all human zinc transporters in normal human organs and in human cancer, especially in pancreatic cancer is not available. The objectives of this study are to investigate the complete expression patterns of 14 ZIP and 10 ZnT transporters in a large number of normal human organs and in human pancreatic cancer tissues and cell lines. We examined the expression patterns of ZIP and ZnT transporters in 22 different human organs and tissues, 11 pairs of clinical human pancreatic cancer specimens and surrounding normal/benign tissues, as well as 10 established human pancreatic cancer cell lines plus normal human pancreatic ductal epithelium (HPDE) cells, using real time RT-PCR and immunohistochemistry. The results indicate that human zinc transporters have tissue specific expression patterns, and may play different roles in different organs or tissues. Almost all the ZIPs except for ZIP4, and most ZnTs were down-regulated in human pancreatic cancer tissues compared to the surrounding benign tissues. The expression patterns of individual ZIPs and ZnTs are similar among different pancreatic cancer lines. Those results and our previous studies suggest that ZIP4 is the only zinc transporter that is significantly up-regulated in human pancreatic cancer and might be the major zinc transporter that plays an important role in pancreatic cancer growth. ZIP4 might serve as a novel molecular target for pancreatic cancer diagnosis and therapy.

MicroRNA-34b inhibits pancreatic cancer metastasis through repressing Smad3

Pancreatic cancer is characterized by extremely poor prognosis because of early recurrence and metastasis, and increasing evidence supports the critical role of microRNA in cancer progression. Here we identified that microRNA-34b functioned as a tumor-suppressing microRNA by targeting oncogenic Smad3 in pancreatic cancer. As a hypovascular tumor with a potential endoplasmic reticulum stress microenvironment, miR-34b was silenced after ER stress inducer thapsigargin (Tg) treatment and negatively regulated by ER stress chaperone glucose regulated protein 78 (GRP78) in pancreatic cancer cells. In human specimens, we found that miR-34b was down-regulated in pancreatic cancer tissues and low level of miR-34b expression was positively correlated with tumor-node-metastasis (TNM) stage, lymph-node metastasis and overall survival. Functional assays showed that over-expression of miR-34b inhibited pancreatic cancer progression in vitro and in vivo. In addition, Smad3 was demonstrated as a direct target of miR-34b and negatively regulated by miR- 34b at mRNA and protein levels. Luciferase assays confirmed that miR-34b could directly bind to the 3'untranslated region of Smad3. An inverse correlation between miR-34b and Smad3 was observed in 64 pancreatic cancer tissues. Our findings indicate that miR-34b acts as a tumor metastasis suppressor through negatively modulating Smad3, which may provide a potential therapeutic strategy for pancreatic cancer.

[Epiphysis preserving by physeal distraction for treatment of femur osteosarcoma in children]

OBJECTIVE

To analyze the effectiveness and application value of epiphysis preserving by the method of physeal distraction for treatment of femur osteosarcoma in children's limb saving surgery.

METHODS

Between January 2007 and January 2011, 6 patients with femur osteosarcoma underwent epiphysis preserving operation by physeal distraction. There were 4 males and 2 females with a mean age of 11.4 years (range, 9-14 years). The mean disease duration was 4.8 months (range, 1-9 months). The pathology confirmed osteosarcoma in all patients by core needle or open biopsy, including 1 case of osteogenic sarcoma, 1 case of chondroblastic osteogenic sarcoma, 1 case of osteoblastic osteogenic sarcoma, and 3 cases of no classified osteosarcoma. The clinical stage was IIA in 1 case and IIB in 5 cases according to the Enneking staging system. All patients received 2 cycles of neoadjuvant chemotherapy before operation. Then physeal distraction was performed for 4-7 days (mean, 5.7 days) based on Cañiadell technique. After 1-2 days of physeal distraction, massive allograft bones and interlocking intramedullary nails were used to reconstruct bone defect after tumor resection. All patients received another 4-6 cycles of chemotherapy and were followed up. Bone healing, limb discrepancy, and complications were recorded. Functional outcomes were assessed by the system of the Musculoskeletal Tumor Society (MSTS) and the range of motion (ROM) of both knee joints.

RESULTS

Superficial infection occurred in 1 case and was cured after dressing change, and primary healing was obtained in the other patients. All 6 patients were followed up 2.5 years on average (range, 1-5 years). Symptoms of pain and swelling disappeared. No complication of allograft rejection, loosening or breaking of fixation occurred. No relapse or metastasis happened during follow-up. Bone healing was observed at the metaphysis junction in 5 cases at 6-9 months after operation and in 1 case at 14 months. Delayed union happened at the diaphysis junction in all patients. Different amount of callus formation was seen at the surface of diaphysis junction, but the fracture line remained clear at 12-48 months after operation. At last follow-up, limb discrepancy was 1-3 cm in 4 patients and 3-5 cm in 2 patients; 3 patients had compensatory scoliosis, and 2 patients had claudication. The MSTS score was 27.20 +/- 1.92, showing significant difference (t= -4.12, P=0.00) when compared with preoperative score (19.60 +/- 2.74). The ROM of affected knee was (127.00 +/- 17.89)0, showing no significant differences when compared with preoperative ROM (109.00 +/- 12.45) degrees (t= -1.84, P=0.10) and with ROM of normal knee (126.00 +/- 9.62)degrees (t= 0.11, P=0.92).

CONCLUSION

Limb saving surgery by physeal distraction can be used in young patients with open epiphyseal plate, which has the advantages of simple operation, good effectiveness, and less complications.

Profilin 1 potentiates apoptosis induced by staurosporine in cancer cells

The correlation between the loss of Profilin 1 (Pfn1) with tumor progression indicated that Pfn1 is a tumor suppressor in human carcinoma. The molecular mechanisms underlying Pfn1 tumor suppression has yet to be elucidated. In this study, we showed that Pfn1 overexpression sensitizes cancer cells to apoptosis through the typical intrinsic apoptotic pathway. Mechanistically, the increased Pfn1 expression mediated the upregulation of p53R273H, one of the most common tumor-associated hotspot mutations of p53, with transactivation deletion in tumorigenesis and increased localization of p53R273H in cytoplasm. Further studies showed that mutant p53R273H was involved in apoptosis induced by Staurosporine (STS) via transcription-independent mitochondrial functions. We observed (i) the increased cytosolic localization of p53R273H, (ii) the activation of phosphorylation at Ser15, (iii) its mitochondrial localization; Pfn1 acted as a positive regulator of these processes. We also found that Pfn1 interacted with p53R273H and thus facilitated its exertion over the transcription-independent activity in the cytoplasm during drug action. Our results define a new function and mechanism of Pfn1 demonstrating that the combined effect with apoptotic agents led to a synergistic increase in apoptosis. In addition, p53R273H abrogating DNA binding was found to play a major role in the Pfn1- sensitized apoptosis through a transactivation-independent and cytosolic activity.

Up-regulation of MBD1 promotes pancreatic cancer cell epithelial-mesenchymal transition and invasion by epigenetic down-regulation of E-cadherin

Methyl-CpG binding domain protein 1 (MBD1) has been implicated in transcriptional regulation, heterochromatin formation, genomic stability, cell-cycle progression and development. It is also predicted that MBD1 might be involved in tumor development and progression. However, whether and how MBD1 is involved in tumorigenesis, especially in pancreatic cancer (PC), is currently unknown. We found that MBD1 was significantly up-regulated in PC tissues compared with the surrounding normal tissues according to RT-PCR data. Tissue microarray (TMA) based immunohistochemical study from 58 surgically resected PC specimens indicated that higher MBD1 expression correlated with lymph node metastasis and poor survival in PC patients. Gain- and loss-of-function studies in vitro validated MBD1 as a potent oncogene promoting PC cell invasion as well as epithelial-mesenchymal transition (EMT). Mechanistically, MBD1 is associated with Twist and NAD-dependent deacetylase sirtuin-1 (SIRT1), thereby forming the Twist-MBD1-SIRT1 complex on the CDH1 promoter, which resulted in reduced E-cadherin transcription activity and increased cell EMT ability. Significantly, targeting MBD1 reversed the EMT phenotype of PC and restored sensitivity to chemotherapy. Taken together, the results of our study revealed a novel function of MBD1 in PC invasion and metastasis by providing a molecular mechanism underlying MBD1-promoted EMT. Thus MBD1 may serve as a potential therapeutic target for PC.

[Epiphyseal distraction for preservation of epiphysis of osteosarcoma in children]

OBJECTIVE

To investigate the feasibility of the preservation of the epiphysis and joint function of the distal femur in children with osteosarcoma with epiphyseal distraction by external fixator.

METHODS

Between July 2007 and May 2011, 6 children with osteoblastic osteosarcoma of the distal femur underwent epiphyseal distraction by external fixator, combined with tumor resection and repair with massive allograft bone transplantation to preserve the epiphysis and joint function of the distal femur. There were 4 boys and 2 girls, aged from 9 to 14 years (mean, 10.5 years). According to Enneking clinical staging, 4 cases were in stage II A and 2 cases in stage II B. According to San-Julian et al. typing for metaphyseal tumor invasion, 3 cases were in type I and 3 cases in type II. The size of tumor ranged from 6 cm x 4 cm to 12 cm x 9 cm. All patients received 2 cycles of COSS 86 chemotherapy before operation and 4 cycles after operation.

RESULTS

Poor healing of incision was observed in 1 case because of rejection of allograft bone and good healing was obtained after the symptomatic treatment, healing of incision by first intention was achieved in the other children. All 6 cases were followed up 11 to 56 months (mean, 37.5 months). One case died of lung metastasis at 2 years after operation. X-ray films showed no complication of internal fixator loosening and broken or bone nonunion. According to the functional evaluation criteria of International Society of Limb Salvage (ISOLS) at last follow-up, the results were excellent in 3 cases, good in 2 cases, and fair in 1 case; the excellent and good rate was 83.3%. The length of operated limb was (62.97 +/- 7.51) cm, showing significant difference when compared with that of normal limb [(64.03 +/- 7.47) cm] (t=0.246 6, P=0.813 4).

CONCLUSION

On the premise of adaptable indication, effective chemotherapy, and thoroughly tumor resection, the epiphyseal distraction by external fixator can obtain satisfactory results in limb-length and limb function in children with osteoblastic osteosarcoma of the distal femur.

Comparative fasting bioavailability and pharmacokinetic properties of 2 formulations of glucosamine hydrochloride in healthy Chinese adult male volunteers

Glucosamine (CAS 66-84-2) hydrochloride is an amino monosaccharide indicated for the treatment of arthrosis, especially osteoarthritis of the knee joint. This study was conducted to assess and compare the pharmacokinetic (PK) properties, bioavailability of a newly developed dispersible tablet formulation (test) of glucosamine hydrochloride with those of an established branded capsule formulation (reference) in healthy Chinese adult male volunteers.This single-dose, randomized, open-label, 2-period crossover study was conducted in 18 healthy Chinese adult male volunteers under fasting condition. Plasma samples were collected at pre-specified times over a 12-h period following administration in each period and analyzed the plasma glucosamine concentrations by Liquid Chromatography coupled with Tandem Mass Spectrometry (LC/MS/MS) method. The mean (SD) PK parameters of Cmax, Tmax, AUC0-12, and AUC0-∞ after administration of the test and reference formulations were, respectively, as follows: Cmax, 907.01 (444.22) vs. 944.40 (429.89) ng/mL, Tmax, 3.03 (0.95) vs. 3.30 (0.99) hours, AUC0-12, 2891.41 (1352.30) vs. 2889.69 (925.48) ng/mL/h, and AUC0-∞, 3029.90 (1321.36) vs. 3091.87 (870.36) ng/mL/h. The mean (SD) t1/2 was 1.10 (0.52) hours for the test formulation and 1.50 (1.17) hours for the reference formulation. On ANOVA, neither period nor sequence effects were observed for any PK properties. The relative bioavailability of the test formulation was 98.3% assessed by AUC0-12. The 90% CIs of glucosamine for the log-transformed ratios of Cmax, AUC0-12, and AUC0-∞ were 78.4-113.9%, 80.8-108.5% and 80.8-105.8%, respectively, meeting the predetermined criteria for bioequivalence of SFDA.

SU-E-J-205: Modeling Fiducial Marker Movement in Prostate

PURPOSE

To understand fiducial marker movement in prostate and to improve prostate patient positioning with fiducial markers.

METHODS

Patient planning CT and positioning CBCT were retrospectively analyzed. CBCT images were automatically registered to the corresponding CT ones based on their bony structures in Eclipse. The coordinates of the markers in the CT and CBCT were recorded. The status of bladder and rectum fillings, and gas in rectum were indexed into four levels and recorded. An algorithm was developed to optimally register the (three) fiducial markers in CBCT with those in the CT so that only the information on prostate deformation and marker migration remained. A mathematical model was built to estimate the marker migration and the relative contribution to the deformation from the status change of bladder and rectum.

RESULTS

The registration error from our optimal registration algorithm indicates the minimal patient setup error by using fiducial markers. The results from our analyzed 3 patients were average(standard deviation) = 1.10(0.40), 1.27(0.67) and 0.62(0.38) mm, but there were some fractions when the registration errors were over 2 mm. From our mathematical model, it was found that the marker migration could be as large as 2.9 mm. If 2 mm tolerance is required in such as SBRT, then soft tissue based registration may be more appreciated when the optimal registration error is greater than 2 mm or from the date when the migration is greater than 2 mm because the migrated marker may not change the location thereafter. In addition, for one investigated patient, the relative contribution to the deformation from the bladder, rectum filling and gas in the rectum is 0.43:0.31:0.26. More patient data are in analysis, and other interesting results will be reported.

CONCLUSIONS

Fiducial marker migration can be over 2 mm. The migration will Result in a conclusion that small registration error does not mean good patient positioning.

Changes in cortical bone response to high-fat diet from adolescence to adulthood in mice

Diabetic obesity is associated with increased fracture risk in adults and adolescents. We find in both adolescent and adult mice dramatically inferior mechanical properties and structural quality of cortical bone, in agreement with the human fracture data, although some aspects of the response to obesity appear to differ by age.

INTRODUCTION

The association of obesity with bone is complex and varies with age. Diabetic obese adolescents and adult humans have increased fracture risk. Prior studies have shown reduced mechanical properties as a result of high-fat diet (HFD) but do not fully address size-independent mechanical properties or structural quality, which are important to understand material behavior.

METHODS

Cortical bone from femurs and tibiae from two age groups of C57BL/6 mice fed either HFD or low-fat diet (LFD) were evaluated for structural and bone turnover changes (SEM and histomorphometry) and tested for bending strength, bending stiffness, and fracture toughness. Leptin, IGF-I, and non-enzymatic glycation measurements were also collected.

RESULTS

In both young and adult mice fed on HFD, femoral strength, stiffness, and toughness are all dramatically lower than controls. Inferior lamellar and osteocyte alignment also point to reduced structural quality in both age groups. Bone size was largely unaffected by HFD, although there was a shift from increasing bone size in obese adolescents to decreasing in adults. IGF-I levels were lower in young obese mice only.

CONCLUSIONS

While the response to obesity of murine cortical bone mass, bone formation, and hormonal changes appear to differ by age, the bone mechanical properties for young and adult groups are similar. In agreement with human fracture trends, adult mice may be similarly susceptible to bone fracture to the young group, although cortical bone in the two age groups responds to diabetic obesity differently.

[Comparison study on different flaps in repairing defect caused by resection of cutaneous malignant melanoma in the heel region]

OBJECTIVE

To compare the clinical effectiveness of the medial plantar flap, the retrograde posterior tibial vascular flap, and the reverse sural neurocutaneous flap in repairing defect caused by resection of cutaneous malignant melanoma (CMM) in the heel region.

METHODS

The clinical data were retrospectively analysed from 24 patients with defect who had CMM in the heel region and were treated by radical excision and flap repairing between March 2007 and March 2010. Defects were repaired with the reverse sural neurocutaneous flaps of 8 cm x 7 cm-14 cm x 12 cm at size in 12 patients (group A), with the medial plantar flaps of 6 cm x 5 cm-8 cm x 7 cm at size in 7 patients (group B), and with the retrograde posterior tibial vascular flaps of 9 cm x 7 cm-15 cm x 13 cm at size in 5 patients (group C). There was no significant difference in gender, age, duration of illness, clinical stage, and size of CMM among 3 groups (P > 0.05). The donor site was sutured directly or by free skin graft.

RESULTS

No significant difference was found in the operation time and the intraoperative blood loss among 3 groups (P > 0.05). All skin flaps or grafts survived and wounds healed by first intention. The patients were followed up 1-3 years. The flaps had normal texture and color with no ulcer in 3 groups. At 1 year after operation, the sensory recovery rates of the flaps were 0, 100%, and 20% in groups A, B, and C, respectively, showing significant difference among 3 groups (P=0.001). The patients had normal appearance of heel and pain-free walking [10 (83%) in group A, 6 (86%) in group B, and 4 (80%) in group C] of heel region, showing no significant difference among 3 groups (Chi(2)=40.000, P=0.135). Heel pain existed in weightbearing walking of 3 groups, and there were significant differences in visule analogue scale (VAS) score (P < 0.05). There was no significant difference in range of motion of ankle joint among 3 groups (P > 0.05). Except 1 patient of relapse in group A at 1 month after operation, no relapse was observed in the other patients during follow-up.

CONCLUSION

The medial plantar flap, the retrograde posterior tibial vascular flap, and the reverse sural neurocutaneous flap can achieve the good clinical effectiveness in treating heel defect caused by the resection of CMM. And the medial plantar flap is the first choice in small skin defect of heel area.