Abnormal expression of MAPK, EGFR, CK17 and TGk in the skin lesions of chloracne patients exposed to dioxins

Objective

Chloracne is one of the most sensitive and specific hallmark of dioxin intoxication. Although its clinical features are clearly described, poor understanding of the molecular pathways of dioxin-induced chloracne hampers a rational approach to therapy. The aim of the present study was to investigate the role of EGFR, MAPK, CK17, and TGk in the pathogenesis of chloracne related to dioxin exposures.

Methods

Epidermal tissues of twelve chloracne patients exposed to dioxins were compared with tissues from 12 healthy controls. These skin tissues were obtained by punch biopsies. p-EGFR and p-MAPK were examined by immunofluorescence. The mRNA and protein levels of CK17 and TGk were examined by fluorescence in situ hybridization and immunohistochemistry, respectively.

Results

p-EGFR and p-MAPK were found in all chloracne tissues, whereas no expression was found in the controls. CK17 mRNA and protein were also found in all chloracne lesions, but none in controls (P = 0.000). TGk mRNA and protein were detected in both groups, but the distribution was distinct. The positive signals in the controls were mainly in the stratum granulosum, while in the chloracne tissues, the positive signals were found more significantly in the stratum granulosum and stratum spinosum.

Conclusions

The results demonstrate that in the human skin the activation of mitogen-activated protein kinase pathway and up-regulation of CK17 and TGK may play roles in the pathogenesis of chloracne related to dioxin exposures.     

PTK (protein tyrosine kinase)-6 and HER2 and 4, but not HER1 and 3 predict long-term survival in breast carcinomas

The HER receptors are of therapeutic and prognostic significance in breast cancer, and their function is modulated by cytoplasmic tyrosine kinases like PTK6 (brk). We performed a retrospective study on archival breast cancer samples from patients with long follow-up and compared the protein expression between individual HERs and between HERs and the PTK6. Univariate and multivariate analyses were used to study the prognostic value of parameters. Metastases-free survival of patients for longer than 240 months was inversely associated (P< or =0.05) with nodal status, tumour size, and oestrogen receptor status, but was also directly associated with high protein expression levels of HER4 and PTK6 in Kaplan-Meier analysis. In multivariate analysis for metastases-free survival of >240 months, the stepwise selected parameters were tumour size (relative risk 3.1), PTK6 expression (0.4), and number of positive lymph nodes (1.2). Furthermore, we demonstrated a timedependence of the prognostic value attributed to the parameters. The HER receptors (HER2,4), but not PTK6, were independent prognostic markers for metastases-free survival at 60 months, whereas at 240 months PTK6 is the strongest prognostic marker. We demonstrate that PTK6 is a prognostic marker of metastases-free survival in breast cancer, and is independent of the classical morphological and molecular markers of lymph node involvement, tumour size, and HER2 status.     

Genome-wide association study of Alzheimer's disease

In addition to apolipoprotein E (APOE), recent large genome-wide association studies (GWASs) have identified nine other genes/loci (CR1, BIN1, CLU, PICALM, MS4A4/MS4A6E, CD2AP, CD33, EPHA1 and ABCA7) for late-onset Alzheimer''s disease (LOAD). However, the genetic effect attributable to known loci is about 50%, indicating that additional risk genes for LOAD remain to be identified. In this study, we have used a new GWAS data set from the University of Pittsburgh (1291 cases and 938 controls) to examine in detail the recently implicated nine new regions with Alzheimer''s disease (AD) risk, and also performed a meta-analysis utilizing the top 1% GWAS single-nucleotide polymorphisms (SNPs) with P<0.01 along with four independent data sets (2727 cases and 3336 controls) for these SNPs in an effort to identify new AD loci. The new GWAS data were generated on the Illumina Omni1-Quad chip and imputed at ∼2.5 million markers. As expected, several markers in the APOE regions showed genome-wide significant associations in the Pittsburg sample. While we observed nominal significant associations (P<0.05) either within or adjacent to five genes (PICALM, BIN1, ABCA7, MS4A4/MS4A6E and EPHA1), significant signals were observed 69–180 kb outside of the remaining four genes (CD33, CLU, CD2AP and CR1). Meta-analysis on the top 1% SNPs revealed a suggestive novel association in the PPP1R3B gene (top SNP rs3848140 with P=3.05E–07). The association of this SNP with AD risk was consistent in all five samples with a meta-analysis odds ratio of 2.43. This is a potential candidate gene for AD as this is expressed in the brain and is involved in lipid metabolism. These findings need to be confirmed in additional samples.     

酪氨酸激酶Syk两种蛋白异构体在乳腺癌细胞内的分布

目的 观察长脾脏酪氨酸激酶[Syk（L）]和短脾脏酪氮酸激酶[Syk（S）]在乳腺癌细胞中的分布。方法 采用胞核、胞质分离技术和Western blot的方法检测乳腺癌细胞系BT474和MIM68中两种Syk蛋白异构体的细胞内分布。构建表达Syk（L）或Syk（S）的MIM35稳定细胞克隆，采用细胞胞核、胞质分离方法和免疫组织化学的方法观察Syk（L）及Syk（S）在细胞内的分布。结果 在乳腺癌细胞系BT474和MIM68中，Syk（L）在细胞质、细胞核内均有表达，Syk（S）只表达在细胞质中。MB435-Syk（L）稳定细胞株中的Syk（L）在细胞质、细胞核内均有表达，MB435-Syk（S）稳定细胞株中的Syk（S）只分布在细胞质内。结论 在乳腺癌细胞中，Syk（L）可由细胞质移位到细胞核内，而Syk（S）只存在于细胞质中。Syk（L）的抑癌功能可能与它的细胞核内功能有关。     

Hexachlorobenzene-induced early changes in ornithine decarboxylase and protein tyrosine kinase activities, polyamines and c-Myc, c-Fos and c-Jun proto-oncogenes in rat liver.

Hexachlorobenzene (HCB) is a lipophilic chemical compound that is widely distributed in the environment. HCB is known to cause liver tumors in experimental animals. In the present study the in vivo effect of HCB treatment on ornithine decarboxylase (ODC) and protein tyrosine kinase (PTK) activities, free polyamine content, and c-Myc, c-Fos, and c-Jun protein levels in rat liver were investigated. HCB (1000 mg/kg body weight) increased hepatic immunodetectable c-Myc, c-Fos, and c-Jun levels after 6 h, and ODC activity and spermine and putrescine content after 18 and 24 h, while maximum stimulation of PTK activity occurred at 12 h. PTK and ODC activities varied in a dose-dependent manner. The time-course of c-Myc, c-Fos, and c-Jun protein levels was different for each proto-oncogene. They were all elevated at the second day of treatment, while only c-Fos and c-Jun remained elevated after 10 days of HCB exposure. These data jointly suggest that the increase in ODC activity may be the consequence of proto-oncogene induction. The alterations in PTK activity suggest that the growth factor signal transduction pathway may be involved in the regulation of the proto-oncogene levels or/and ODC activity. The decrease in PTK activity after the first day, even in the presence of alpha-D-Difluoromethylornithine (DFMO), an inhibitor of ODC activity, suggests that it is not regulated by polyamines. These results may be relevant to the early molecular events involved in HCB tumor promoter activity in rat liver.     

Progress of targeted and immunotherapy for hepatocellular carcinoma and the application of next-generation sequencing

Hepatocellular carcinoma (HCC), leading cancer worldwide, has a high degree of genetic heterogeneity; next-generation sequencing (NGS) technology has contributed significantly to the discovery of driving genes as well as high-frequency mutations in HCC. The detection of gene alterations may allow us to predict prognosis and adverse drug reactions for individuals, paving the way for personalized medicine in HCC patients. In this review, we summarized the common systemic therapy regimens for HCC and the predictive efficacy of genetic biomarkers on the prognosis of patients under these treatments. Finally, we put forward a future perspective on the potential of NGS technology for the guidance of targeted therapy and immunotherapy in HCC.     

Signal Transduction of Chemokine Platelet Factor 4 in Human Erythroleukemia Cells

Previous data have demonstrated that CXC-chemokine platelet factor 4 (PF4) inhibits the proliferation of the human erythroleukemia cell line (HEL). However, the mechanism of action is unclear at present. The signaling transduction induced by PF4 in the HEL was compared with that induced by transforming growth factor beta1 (TGF-beta1), which is also a potent inhibitor of HEL growth. It was found that PF4 had no inhibitory effect on intracellular calcium levels in resting HEL cells. When HEL cells were stimulated with interleukin-3 (IL-3), a rapid increase in the intracellular level of free calcium occurred within 15 to 20 seconds, and this increase was followed by a sustained increase that gradually declined until resting levels were reached 30 to 40 minutes later. PF4 dramatically decreased the transient rise of [Ca2+] and protein kinase C (PKC) activity of HEL cells induced by IL-3. However, PF4 had no inhibitory effect on PKC activation in resting HEL cells. Furthermore, PF4 was found to down-regulate significantly protein tyrosine kinase (PTK) activity. In contrast, TGF-beta1 induced an increase in intracellular free calcium concentration and PKC and PTK activity in HEL cells. Furthermore, PF4 significantly increased the messenger RNA (mRNA) level of p21waf1 in HEL cells. These data demonstrate that PF4 acts on HEL cells through a signaling transduction pathway, which is different from that of TGF-beta1 and is related to the up-regulatory mRNA level of p21waf1 in HEL cells.     

PTK2 and PTPN11 expression in myelodysplastic syndromes

OBJECTIVE:

The aim of this study was to evaluate the expression of protein tyrosine kinase 2 and protein tyrosine phosphatase non-receptor type 11, which respectively encode focal adhesion kinase protein and src homology 2 domain-containing protein-tyrosine phosphatase 2, in hematopoietic cells from patients with myelodysplastic syndromes.

METHODS:

Protein tyrosine kinase 2 and tyrosine phosphatase non-receptor type 11 expressions were analyzed by quantitative polymerase chain reaction in bone marrow cells from patients with myelodysplastic syndromes and healthy donors.

RESULTS:

Protein tyrosine kinase 2 and tyrosine phosphatase non-receptor type 11 expressions did not significantly differ between normal cells and myelodysplastic cells.

CONCLUSIONS:

Our data suggest that despite the relevance of focal adhesion kinase and src homology 2 domain-containing protein-tyrosine phosphatase 2 in hematopoietic disorders, their mRNA expression do not significantly differ between total bone marrow cells from patients with myelodysplastic syndromes and healthy donors.     

准分子激光治疗性角膜切削术后兔角膜蛋白多糖的变化

目的通过观察准分子激光治疗性角膜切削术后角膜蛋白多糖的变化,探讨角膜上皮下雾状混浊与蛋白多糖的关系。方法对12只(24只眼)新西兰大白兔行准分子激光屈光性角膜切削术,切削深度130μm,制作角膜上皮下雾状混浊动物模型。8周后对2~3级角膜上皮下雾状混浊行准分子激光治疗性角膜切削术。用裂隙灯显微镜对角膜上皮下雾状混浊评分,并进行角膜蛋白多糖超微结构组织化学染色观察。结果准分子激光治疗性角膜切削术后角膜上皮下雾状混浊减轻或消除,异常蛋白多糖明显减少。结论准分子激光治疗性角膜切削术可有效治疗准分子激光屈光性角膜切削术后角膜上皮下雾状混浊,角膜上皮下雾状混浊与异常蛋白多糖密切相关。     

桂枝挥发油对LPS致急性肺损伤大鼠模型蛋白酪氨酸激酶活性的影响

目的探讨桂枝挥发油对LPS致大鼠急性肺损伤模型蛋白酪氨酸激酶活性的影响;方法采用LPS 1 mg/kg尾静脉注射构建大鼠急性肺损伤模型,取肺组织,采用ELISA方法检测不同干预组肺组织中PTK含量,比较组间差异;结果研究表明,SD大鼠正常肺组织中PTK含量为(44.21±31.51)pmol/mL;模型组含量为(173.58±97.95)pmol/mL,较空白组显著增高,具有极显著的统计学意义(P＜0.001);VORC高、中、低3个剂量组PTK含量均较模型组显著降低(P＜0.05),有一定的量效关系.结论桂枝挥发油能够抑制LPS所致大鼠急性肺损伤肺组织中PTK的异常增高,对PTK活性的抑制可能是桂枝挥发油发挥抗炎作用的主要机制之一.