Blocking TrkB-BDNF signal pathway decreases the livability of neuroblastoma cells / 中国当代儿科杂志

<p><b>OBJECTIVE</b>Brain-derived neurotrophic factor (BDNF) and its specific tryrosin kinase receptor-B (TrkB) are highly correlated to the chemoresistance of neuroblastoma (NB) cells and poor prognosis. This study observed the changes of the sensibility of NB cells to chemotherapy drug cisplatin (CDDP) before and after blockage of TrkB-BDNF signal pathway by specific tyrosin kinase inhibitor K252a.</p><p><b>METHODS</b>Human NB cell line SH-SY5Y (SY5Y) was routinely cultured. Expression of TrkB was induced with nM all trans-retinoid acid (ATRA). Then BDNF, CDDP or K252a were added to the cultured SY5Y cells. Cell livability was assessed by methyl thiazolyl tetrazolium (MTT) assay. TrkB autophosphorylation was determined by Western blot analysis. Cell apoptosis rate was detected by flow cytometry (FCM). The conformation of apoptosis cells was observed by transmission electron microscopy (TEM).</p><p><b>RESULTS</b>The livability and apoptosis rate in SY5Y cells treated with ATRA, BDNF and CDDP were not different from the blank control group. However, after K252a together with ATRA, BDNF and CDDP treatment, the sensibility of SY5Y cells to chemotherapy drug CDDP increased, the livability decreased and the apoptosis rate increased in SY5Y cells when compared with the blank control group (P <0.01). K252a treatment resulted in blockage of TrkB autophosphorylation.</p><p><b>CONCLUSIONS</b>The blockage of TrkB-BDNF signal pathway by K252a use can increase sensibility of NB cells to chemotherapy and thus decrease the livability of NB cells.</p>

Expression of fusion gene PAX3/PAX7-FKHR and chromosomal aberration in rhabdomyosarcoma / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To detect the PAX3/PAX7-FKHR fusion transcripts to identify genetic alteration in embryonal rhabdomyosarcoma (ERMS) and alveolar rhabdomyosarcoma (ARMS) tissues.</p><p><b>METHODS</b>One-step reverse transcription- polymerase chain reaction (RT-PCR) were used to detect the expression of the PAX3/PAX7-FKHR fusion transcrips in 16 cases of rhabdomyosarcoma (7 cases of ARMS, 9 cases of ERMS) and 16 specimens were compared to the surrounding normal tissue. Comparative genomic hybridization (CGH) was employed to detect the genomic imbalance (DNA loss or amplification) in 16 RMS cases.</p><p><b>RESULTS</b>PAX3-FKHR fusion transcripts were positive in 3/7 and PAX 7-FKHR fusion transcripts were positive in 2/7 of ARMS patients, respectively, and were all negative in ERMS and Control tumors. There were different chromosome variations for each RMS, chromosome amplification was frequently seen in 1p36 (69%), 5q32 (56%), 8q21 (63%), 13q14 (69%), 19q (63%), 20q (56%). Chromosome loss was frequently seen in 3p21-pter (56%), 9p23-pter (50%), 10q (69%), 16/16q24 (56%).</p><p><b>CONCLUSION</b>One-step RT-PCR assay for detection specific fusion gene provides a useful tool for confirmation of the diagnosis of RMS in diagnostically difficult cases and in retrospective studies. Chimeric gene transcript resulting from specific chromosomal translocations is a reliable index for the molecular diagnosis of RMS.</p>

Solid cystic papillary tumor of pancreas in eight children / 中国医学科学杂志(英文版)

<p><b>OBJECTIVE</b>To estimate the clinical and pathological features of pancreatic solid cystic papillary tumor (SCPT) in children.</p><p><b>METHODS</b>From 2000 to 2005, 8 cases with SCPT of the pancreas were analyzed retrospectively. All cases but one were females. Average age was 12.8 years. By case review, we discussed the clinical and pathological features of SCPT in children.</p><p><b>RESULTS</b>The chief complains were abdominal pain and palpable mass. There were 3 cases in the head, 1 case in the body, and 4 cases in the tail of pancreas. The procedures employed included local resection (1 case), distal pancreatectomy (5 cases), pancreaticoduodenectomy (1 case), and biopsy (1 case). Histological examination showed solid with cystic areas and papillary protrusions in the 8 cases; as for immunohistochemical examinations, the positive rate was 100% for alpha-antitrypsin (AACT), 87.5% for vinmentin, and 62.5% for neuron-specific enolase (NSE). The patients were followed up for 2 months to 4 years but one was lost by follow-up and all were alive postoperatively. SCPT in 2 cases relapsed.</p><p><b>CONCLUSION</b>Occurring predominantly in young females, SCPT is usually curable by surgical resection with a favorable prognosis.</p>

Genomic imbalance and chromosome disorders in hepatoblastoma / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To establish stable techniques of comparative genomic hybridization (CGH) and apply them to elucidate the genetic characteristics of hepatoblastoma (HB), and to explore the characteristics and clinical significance of loss of heterozygosity (LOH) at 1p36 in HB.</p><p><b>METHODS</b>CGH was employed to detect the genomic imbalance (DNA loss or amplification) in 20 cases of HB, and PCR-simple repeated sequence polymorphism was employed in 30 cases of HB to detect the loss of heterozygosity for 6 satellites at chromosome 1p36.</p><p><b>RESULTS</b>There were different chromosome variations for each HB. chromosome amplification was frequently seen in 1q, 2q,2p, 8q, 8p, 12q and 22q. Chromosome loss was often seen in 1p, 4q, 4p, 16q, 17p and 18q. The frequency of LOH at 6 loci on chromosome 1 was 63.3% totally (19/30), with the highest D1S199 (66.7%) and D1S450 next to it (46.7%).</p><p><b>CONCLUSION</b>There were chromosome zones with DNA amplification or loss in hepatoblastoma. There are extensive LOH at 1p36 in hepatoblastoma. The corresponding amplification of oncogene and loss of antioncogene may take part in the development of hepatoblastoma.</p>

Effects of tyrosine kinase receptor B and brain-derived neurotrophic factor on chemoresistance in neuroblastoma / 中华儿科杂志

<p><b>OBJECTIVE</b>Neuroblastoma (NB) is a pediatric solid tumor derived from neural crest precursor cells. It is resistant to current therapeutic protocols, including high dose chemotherapy. The mechanisms of chemoresistance are very complex. The recent studies have shown that the levels of tyrosine kinase receptor B (TrkB) and brain-derived neurotrophic factor (BDNF) are high in NB tumors with poor prognosis. The aim of this research was to explore the effects of TrkB and BDNF levels on the chemotherapeutic sensitivity in neuroblastoma by using the NB cell line SH-SY5Y in vitro.</p><p><b>METHODS</b>The expression of TrkB protein was detected with Western-blot after the treatment with different concentrations of all trans-retinoic acid (ATRA). Cell survival rate was analyzed using MTT. Apoptosis was detected using flow cytometry (FCM) and a transmission electron microscope (TEM).</p><p><b>RESULTS</b>(1) The expression of TrkB protein was undetectable in SY5Y. It was positive, however, after the treatment with ATRA (1, 10, 100 nmol/L) for five days. The level of TrkB protein was increased with adding of ATRA at different concentrations. (2) The difference of the survival and apoptotic rate between the BDNF (10 ng/ml) + ATRA (10 nmol/L) + cisplatin (CP, 5 microg/ml) group (survival rate 46.51% +/- 13.44%, apoptosis rate 11.79% +/- 1.53%) and the CP alone group (survival rate 38.51% +/- 9.66%, apoptosis rate 14.95% +/- 2.06%) was not statistically significant (P > 0.05). The survival rate of the BDNF (50 ng/ml and 100 ng/ml) + ATRA (10 nmol/L) + CP (5 microg/ml) group (66.85% +/- 18.39%, 94.30% +/- 10.71%) was greatly higher than CP alone group (P < 0.05, P < 0.01), whereas the apoptotic rate (9.36% +/- 1.03%, 5.20% +/- 1.99%) was significantly lower than that of the CP alone group (P < 0.01, P < 0.01). The survival rates of BDNF (100 ng/ml) + ATRA (10 nmol/L) + CP (5 microg/ml) group were higher than those of BDNF (50 ng/ml) + ATRA (10 nmol/L) + CP (5 microg/ml) group (P < 0.01), whereas the apoptotic rates were lower than those of BDNF (50 ng/ml) + ATRA (10 nmol/L) + CP (5 microg/ml) group (P < 0.05). There were no significant difference between the ATRA (1 nmol/L) + BDNF (50 ng/ml) + CP group (survival rate 45.33% +/- 11.83%, apoptosis rate 12.48% +/- 2.48%) and the CP alone group in the survival and apoptotic rates (P > 0.05). The survival rates of the ATRA (10 nmol/L, 100 nmol/L) + BDNF (50 ng/ml) + CP (61.62% +/- 18.53%, 105.02% +/- 5.55%) group were greatly higher than those of the CP alone group (P < 0.05, P < 0.01), whereas the apoptotic rate (9.36% +/- 1.03%, 5.05% +/- 1.88%) was significantly lower than that of the CDDP alone group (P < 0.05, P < 0.01). The survival rates of the ATRA (100 nmol/L) + BDNF (50 ng/ml) + CP group were higher than those of the ATRA (10 nmol/L) + BDNF (50 ng/ml) + CP group (P < 0.01), whereas the apoptotic rates were lower than the ATRA (10 nmol/L) + BDNF (50 ng/ml) + CP group (P < 0.01). (3) Some of the cells showed apoptotic changes in the CP alone group, whereas the intranuclear chromoplasma was well-distributed, the nuclear membrane was clear, and mitochondria, ribosome and solvent were present in the ATRA (10 nmol/L) + BDNF (50 ng/ml) + CP group.</p><p><b>CONCLUSIONS</b>The sensitivity of SY5Y to CP was affected by TrkB and BDNF. The higher the level of TrkB and BDNF was, the lower the sensitivity of SY5Y to CP.</p>

Diagnosis and treatment of mediastinal enterogenous cysts in children / 中国医学科学杂志(英文版)

<p><b>OBJECTIVE</b>To investigate the diagnosis and therapy of mediastinal enterogenous cysts in children.</p><p><b>METHODS</b>Clinical data of 17 cases with mediastinal enterogenous cysts within 19 years in our hospital were retrospectively analyzed.</p><p><b>RESULTS</b>One case was intramural esophageal cyst and 16 cases were enteric cysts, two among which were complicated with abdominal enteric duplications. Most cases presented with symptoms of respiratory distress. Twelve cases were complicated with vertebral anomalies. Ultrasound of 12 cases and magnetic resonance imaging of 4 cases were helpful in confirming the cystic nature of these lesions. Eight cases had technetium-99m pertechnetate scintigraphy of posterior mediastinum.</p><p><b>CONCLUSIONS</b>Most patients present with symptoms of respiratory distress, complicated with vertebral anomalies. Ultrasonography and magnetic resonance imaging may be helpful in confirming the cystic nature of these lesions. Technetium-99m pertechnetate scintigraphy is the most effective method for differentiation of the disease from other mediastinal cysts.</p>

Clinical Characteristics of Solid Cystic Papillary Tumor in Children / 实用儿科临床杂志

Objective To explore clinical characteristics of diagnosis and treatment of solid-cystic papillary tumor(SCPT) of the pancreas in children.Methods There were retrospectively analyzed about the 7 patients treated in our hospital for SCPT,with the ave-rage age of 11.5 years.All patients complained abdominal pain following a trauma(71.4%) or overeating(28.6%).The main presentation was abdominal mass.Of the 7 patients,4 received distal pancreatectomy,2 pancreatico-duodenectomy,and 1 only biopsy.Results The nicks of all patients were primany hed.All patients were pathologically confirmed as SCPT after operation.All patients were followed up for 4 monthes to 4.5 years,the recent result was well.Conclusions SCPT is a low-grade malignant tumor,which is often asymptomatic,but the patients with symptoms generally suffer from an abdominal mass or abdominal pain.The prognosis is excellent after operation.

THE COMPARISON OF THE CROSS-SECTION AREA AND VOLUME OF THE GRAY AND WHITE SUBSTANCE OF THE SPINAL CORD IN MAN CAT DOG AND RABBIT / 西安交通大学学报(医学版)

The spinal cords of three men, nine cats, three dogs and four rabbits were chosen for the present investigation. It was found that the thoracic segment of the spinal cord is longer than the other segments in man and animals. The volume of the gray substance in the lumber enlargment are larger than that in the cervical enlargment in man, cat, dog and rabbit, The cross—section areas of the white substance of the spinal cord in man increase clearly at the cranial level but that of the rabbit does not.Based on the measurements we found that the move of the gray substance anteriorly in man and cat may be the mark of evolution of the mammals. Perheps the spinal eord of eat is a satisfectory specimen in neuro anatomical and neurophysiological laboratory.