Gastrointestinal disorders in Curry–Jones syndrome: Clinical and molecular insights from an affected newborn

Curry–Jones syndrome (CJS) is a pattern of malformation that includes craniosynostosis, pre‐axial polysyndactyly, agenesis of the corpus callosum, cutaneous and gastrointestinal abnormalities. A recurrent, mosaic mutation of SMO (c.1234 C>T; p.Leu412Phe) causes CJS. This report describes the gastrointestinal and surgical findings in a baby with CJS who presented with abdominal obstruction and reviews the spectrum of gastrointestinal malformations in this rare disorder. A 41‐week, 4,165 g, female presented with craniosynostosis, pre‐axial polysyndactyly, and cutaneous findings consistent with a clinical diagnosis of CJS. The infant developed abdominal distension beginning on the second day of life. Surgical exploration revealed an intestinal malrotation for which she underwent a Ladd procedure. Multiple small nodules were found on the surface of the small and large bowel in addition to an apparent intestinal duplication that seemed to originate posterior to the pancreas. Histopathology of serosal nodules revealed bundles of smooth muscle with associated ganglion cells. Molecular analysis demonstrated the SMO c.1234 C>T mutation in varying amounts in affected skin (up to 35%) and intestinal hamartoma (26%). Gastrointestinal features including structural malformations, motility disorders, and upper GI bleeding are major causes of morbidity in CJS. Smooth muscle hamartomas are a recognized feature of children with CJS typically presenting with abdominal obstruction requiring surgical intervention. A somatic mutation in SMO likely accounts for the structural malformations and predisposition to form bowel hamartomas and myofibromas. The mutation burden in the involved tissues likely accounts for the variable manifestations.     

MEVITEM—a phase I/II trial of vismodegib + temozolomide vs temozolomide in patients with recurrent/refractory medulloblastoma with Sonic Hedgehog pathway activation

BackgroundVismodegib specifically inhibits Sonic Hedgehog (SHH). We report results of a phase I/II evaluating vismodegib + temozolomide (TMZ) in immunohistochemically defined SHH recurrent/refractory adult medulloblastoma.MethodsTMZ-naïve patients were randomized 2:1 to receive vismodegib + TMZ (arm A) or TMZ (arm B). Patients previously treated with TMZ were enrolled in an exploratory cohort of vismodegib (arm C). If the safety run showed no excessive toxicity, a Simon’s 2-stage phase II design was planned to explore the 6-month progression-free survival (PFS-6). Stage II was to proceed if arm A PFS-6 was ≥3/9 at the end of stage I.ResultsA total of 24 patients were included: arm A (10), arm B (5), and arm C (9). Safety analysis showed no excessive toxicity. At the end of stage I, the PFS-6 of arm A was 20% (2/10 patients, 95% unilateral lower confidence limit: 3.7%) and the study was prematurely terminated. The overall response rates (ORR) were 40% (95% CI, 12.2-73.8) and 20% (95% CI, 0.5-71.6) in arm A and B, respectively. In arm C, PFS-6 was 37.5% (95% CI, 8.8-75.5) and ORR was 22.2% (95% CI, 2.8-60.0). Among 11 patients with an expected sensitivity according to new generation sequencing (NGS), 3 had partial response (PR), 4 remained stable disease (SD) while out of 7 potentially resistant patients, 1 had PR and 1 SD.ConclusionThe addition of vismodegib to TMZ did not add toxicity but failed to improve PFS-6 in SHH recurrent/refractory medulloblastoma. Prediction of sensitivity to vismodegib needs further refinements.     

抗SMO多克隆抗体对DU145前列腺癌细胞生长及侵袭力的影响

目的 探讨抗SMO多克隆抗体对DU145前列腺癌细胞生长及侵袭能力的影响。方法 预测SMO蛋白抗原表位并制备SMO抗体,评估其效价和特异性;实验分组包括空白对照组、兔IgG抗体处理组、抗SMO抗体处理组、shRNA空载对照组、TRPC-6蛋白shRNA稳转细胞处理组以及合并正常IgG抗体和抗SMO抗体处理组。MTT法和细胞凋亡实验检测抗SMO抗体对DU145细胞增殖和细胞凋亡的影响;Transwell实验检测抗SMO抗体对正常以及稳转TRPC-6shRNA蛋白的DU145细胞侵袭能力的影响。结果 制备的抗体效价为1∶51200,且抗体特异性良好;随着抗SMO抗体浓度的升高,细胞存活百分比逐渐下降(P<0.05),随着时间的发展,48h和72h之间的细胞存活百分比存在差异(P<0.05)。凋亡实验显示,早期凋亡细胞(Annexin V⁺/PI-)凋亡百分比在抗SMO抗体处理组较空白对照组中明显升高(P<0.05),随着抗体浓度的升高,凋亡百分比逐渐升高。Transwell实验显示,随着抗SMO抗体的处理,细胞的细胞侵袭抑制率逐渐升高(P<0.05),TRPC-6蛋白shRNA稳转DU145细胞处理组中,随着抗体浓度的升高,细胞的细胞侵袭抑制率逐渐升高(P<0.05)。结论 抗SMO多克隆抗体对正常以及TRPC-6蛋白shRNA稳转的DU145细胞生长以及侵袭能力均有明显的抑制作用,为临床治疗前列腺癌提供一个潜在的方向。     

Effect of Mono-2-ethyhexyl Phthalate on DNA Methylation in Human Prostate Cancer LNCaP Cells

Objective To evaluate whether mono(2‐ethylhexyl) phthalate(MEHP) affects genomic DNA methylation and the methylation status of some specific genes such as patched gene(PTCH) and smoothened gene(SMO) in LNCaP cells. Methods LNCaP cells were treated with MEHP(0, 1, 5, 10, and 25 μmol/L) for 3 days. An ELISA assay was preformed to detect genomic methylation, including 5‐methylcytosine(5‐mC) and 5‐hydroxymethylcytosine(5‐hmC) content. A pyrosequencing assay was applied to assess DNA methylation in PTCH and SMO gene promoters. The correlation between DNA methylation and gene expression was assessed. Results The proportion of cytosines with 5‐mC methylation in LNCaP cells was significantly decreased by MEHP(1, 5, 10, and 25 μmol/L) in a dose‐dependent manner(P 0.01). For genes in the Hedgehog pathway, there was no significant MEHP concentration‐dependent difference in the DNA methylation of PTCH and SMO. Conclusion MEHP might affect the progression of prostate cancer through its effect on global DNA methylation.     

支持向量机基础上的银屑病辅助诊断方法研究

介绍基于支持向量机的银屑病辅助诊断方法实现流程,包括数据收集和预处理、构建数据库群、特征提取、建立基于支持向量机的辅助诊断模型。通过实验验证该方法的有效性,其诊断精度较高,可以为银屑病数据分析、疾病预防提供技术支持。     

Smoothened (SMO) receptor mutations dictate resistance to?vismodegib in basal cell carcinoma

Basal cell carcinomas (BCCs) and a subset of medulloblastomas are characterized by loss‐of‐function mutations in the tumor suppressor gene, PTCH1. PTCH1 normally functions by repressing the activity of the Smoothened (SMO) receptor. Inactivating PTCH1 mutations result in constitutive Hedgehog pathway activity through uncontrolled SMO signaling. Targeting this pathway with vismodegib, a novel SMO inhibitor, results in impressive tumor regression in patients harboring genetic defects in this pathway. However, a secondary mutation in SMO has been reported in medulloblastoma patients following relapse on vismodegib to date. This mutation preserves pathway activity, but appears to confer resistance by interfering with drug binding.Here we report for the first time on the molecular mechanisms of resistance to vismodegib in two BCC cases. The first case, showing progression after 2 months of continuous vismodegib (primary resistance), exhibited the new SMO G497W mutation. The second case, showing a complete clinical response after 5 months of treatment and a subsequent progression after 11 months on vismodegib (secondary resistance), exhibited a PTCH1 nonsense mutation in both the pre‐ and the post‐treatment specimens, and the SMO D473Y mutation in the post‐treatment specimens only. In silico analysis demonstrated that SMOG497W undergoes a conformational rearrangement resulting in a partial obstruction of the protein drug entry site, whereas the SMO D473Y mutation induces a direct effect on the binding site geometry leading to a total disruption of a stabilizing hydrogen bond network. Thus, the G497W and D473Y SMO mutations may represent two different mechanisms leading to primary and secondary resistance to vismodegib, respectively.