Coexistence of multiple rare spinal abnormalities in type 1 neurofibromatosis: a case report and literature review.

Orthopaedic involvement is the most common clinical presentation of Neurofibromatosis type 1 (NF-1) patients with the spinal abnormalities more frequently affected. In the spinal deformities of NF-1 patients, despite the scoliosis is the most frequent finding, several distinctive radiographic features, such as dural ectasia, defective pedicles, and spondylolisthesis, are relatively less common. Here, we reported a 16-year-old boy diagnosed with NF-1 who presented with dural ectasia, defective pedicles, and spondylolisthesis concomitantly, described the surgical treatment and provided a literature review. The boy complained of low back and leg pain for two months. On clinical examination, the patient showed multiple café au lait spots on his back and no neurological deficit. He had a family history of neurofibromatosis as his father suffering from NF-1. Imaging results demonstrated mild scoliosis, posterior scalloping of the lumber spine, L5 spondylolisthesis on plain radiographs, and marked dural ectasia of L3-L5 on MRI. Furthermore, the CT scan showed presence of thin pedicles at L3, bilateral symmetrical pedicle clefts at L4, and pars interarticularis fractures at L5. The patient received a long level posterior fusion from L1 to S1 with pedicle screws. Iliac crest autogenous graft mixed with artificial bone were used to achieve solid arthrodesis. At nine-month follow-up, the patient was asymptomatic and able to live a normal life. Our observation demonstrated that familiarity with those distinctive features in NF-1 patients could be contributed to making an early diagnosis and optimizing treatment.

Protective effects of quercetin on cadmium-induced cytotoxicity in primary cultures of rat proximal tubular cells.

OBJECTIVE: To investigate the protective effects of quercetin on cadmium-induced cytotoxicity in primary cultures of rat proximal tubular (rPT) cells. METHODS: Primary cultures of rPT cells undergoing exponential growth were incubated with 1.0 µg/mL quercetin and/or cadmium (2.5, 5.0 µmol/L), in a serum-free medium at 37 °C at different time intervals. Commercial kits were used and flow cytometric analyses were performed on rPT cell cultures to assay apoptosis and oxidative stress. RESULTS: Exposure of rPT cells to cadmium acetate (2.5, 5.0 µmol/L) induced a decrease in cell viability, caused an increase in apoptotic rate and apoptotic morphological changes. Simultaneously, elevation of intracellular reactive oxygen species, malondialdehyde and calcium levels, depletion of mitochondrial membrane potential and intracellular glutathione, and inhibition of Na+, K+-ATPase, Ca2+-ATPase, glutathione peroxidase (GSH-Px), catalase (CAT), and superoxide dismutase (SOD) activities were revealed during the cadmium exposure of rPT cells. However, simultaneous supplementation with 1 µg/mL quercetin protected rPT cells against cadmium-induced cytotoxicity through inhibiting apoptosis, attenuating lipid peroxidation, renewing mitochondrial function and elevating the intracellular antioxidants (non-enzymatic and enzymic) levels. CONCLUSION: The present study has suggested that quercetin, as a widely distributed dietary antioxidant, contributes potentially to prevent cadmium-induced cytotoxicity in rPT cells.

Epigenetic inactivation of secreted frizzled-related protein 2 in esophageal squamous cell carcinoma.

AIM: To investigate the expression and methylation status of the secreted frizzled-related protein 2 (SFRP2) in esophageal squamous cell carcinoma (ESCC) and explore its role in ESCC carcinogenesis. METHODS: Seven ESCC cell lines (KYSE 30, KYSE150, KYSE410, KYSE510, EC109, EC9706 and TE-1) and one immortalized human esophageal epithelial cell line (Het-1A), 20 ESCC tissue samples and 20 paired adjacent non-tumor esophageal epithelial tissues were analyzed in this study. Reverse-transcription polymerase chain reaction (RT-PCR) was employed to investigate the expression of SFRP2 in cell lines, primary ESCC tumor tissue, and paired adjacent normal tissue. Methylation status was evaluated by methylation-specific PCR and bisulfite sequencing. The correlation between expression and promoter methylation of the SFRP2 gene was confirmed with treatment of 5-aza-2'-deoxycytidine. To assess the potential role of SFRP2 in ESCC, we established stable SFRP2-transfected cells and examined them with regard to cell proliferation, colony formation, apoptosis and cell cycle in vivo and in vitro. RESULTS: SFRP2 mRNA was expressed in the immortalized normal esophageal epithelial cell line but not in seven ESCC cell lines. By methylation-specific PCR, complete methylation was detected in three cell lines with silenced SFRP2 expression, and extensive methylation was observed in the other four ESCC cell lines. 5-aza-2'-deoxycytidine could restore the expression of SFRP2 mRNA in the three ESCC cell lines lacking SFRP2 expression. SFRP2 mRNA expression was obviously lower in primary ESCC tissue than in adjacent normal tissue (0.939 ± 0.398 vs 1.51 ± 0.399, P < 0.01). SFRP2 methylation was higher in tumor tissue than in paired normal tissue (95% vs 65%, P < 0.05). The DNA methylation status of the SFRP2 correlated inversely with the SFRP2 expression. To assess the potential role of SFRP2 in ESCC, we established stable SFRP2 transfectants and control counterparts by introducing pcDNA3.1/v5 hisA -SFRP2 or pcDNA3.1/v5 hisA -empty vector into KYSE30 cells lacking SFRP2 expression. After transfection, the forced-expression of SFRP2 was confirmed by the RT-PCR. In comparison with the control groups, stably-expressed SFRP2 in KYSE 30 cells significantly reduced colony formation in vitro (47.17% ± 15.61% vs 17% ± 3.6%, P = 0.031) and tumor growth in nude mice (917.86 ± 249.35 mm(3)vs 337.23 ± 124.43 mm(3), P < 0.05). Using flow cytometry analysis, we found a significantly higher number of early apoptotic cells in SFRP2-transfected cells than in the control cells (P = 0.025). The mean cell number in the S and G2-M phases of the cell cycle was also significantly lower in SFRP2-transfected KYSE30 cells compared with mock transfected counterparts. CONCLUSION: Silencing of SFRP2 expression through promoter hypermethylation may be a factor in ESCC carcinogenesis through loss of its tumor-suppressive activity.

Aberrant methylation of the 3q25 tumor suppressor gene PTX3 in human esophageal squamous cell carcinoma.

AIM: To identify the novel methylation-silenced gene pentraxin 3 (PTX3) in esophageal squamous cell carcinoma (ESCC). METHODS: PTX3 mRNA expression was examined in six human ESCC cell lines, one human immortalized normal esophageal epithelial cell line, primary ESCC tumor tissue, and paired adjacent nontumor tissue using reverse transcription polymerase chain reaction (RT-PCR). Semi-quantitative immunohistochemistry was used to examine cellular localisation and protein levels. Methylation specific PCR and bisulphite genomic sequencing were employed to investigate the methylation of the candidate gene. RESULTS: In the majority of ESCC cell lines, we found that PTX3 expression was down-regulated due to gene promoter hypermethylation, which was further confirmed by bisulphite genomic sequencing. Demethylation treatment with 5-aza-2'-deoxycytidine restored PTX3 mRNA expression in ESCC cell lines. Methylation was more common in tumor tissues (85%) than in adjacent nontumor tissues (25%) (P < 0 .01). CONCLUSION: PTX3 is down-regulated through promoter hypermethylation in ESCC, and could potentially serve as a biomarker of ESCC.