Distinct progression pathways involving the dysfunction of DUSP6/MKP-3 in pancreatic intraepithelial neoplasia and intraductal papillary-mucinous neoplasms of the pancreas.

DUSP6/MKP-3 is identified as a candidate tumor suppressor gene for pancreatic cancer. The aim of this study was to elucidate the roles of DUSP6 in the pancreatic carcinogenesis through the pancreatic intraepithelial neoplasia and/or intraductal papillary-mucinous neoplasms, both of which are considered to be precursor lesions of invasive carcinoma of the pancreas, by comparing with involvements of other major tumor suppressive pathways. Expressions of DUSP6, CDKN2A, TP53, and SMAD4 were investigated by immunohistochemistry in a total of 206 lesions of dysplastic ductal precursors and carcinomas retrieved from 52 pancreata with invasive ductal carcinomas and 51 of those with intraductal papillary-mucinous neoplasms. The intensity of staining was evaluated in lesions at different atypical grades and statistically compared among them. Mutations of KRAS2 were analyzed by methods of the allele-specific oligonucleotide hybridization and nucleotide sequencing. In pancreata with invasive ductal carcinomas, expressions of DUSP6 were abrogated exclusively in the invasive carcinoma cells in contrast to its fairly preserved expressions in pancreatic intraepithelial neoplasia. In pancreata with intraductal papillary-mucinous neoplasms, abrogated expressions of DUSP6 were observed in a relatively small fraction of intraductal adenoma/borderlines and intraductal carcinomas. Most of the intraductal adenoma/borderline lesions with abrogation of DUSP6 harbored mutations of KRAS2. None of the molecules was associated with each other in any grade of lesions. Morphological variations of papillae of the intraductal papillary-mucinous neoplasms were evaluated and analyzed for their associations with abrogations of the molecules, which resulted in finding of no significant associations. Our results suggest that the abrogation of DUSP6 is associated exclusively with progression from pancreatic intraepithelial neoplasia to the invasive ductal carcinoma while it is potentially associated with initiation of intraductal papillary-mucinous neoplasms with mutated KRAS2, which is independent of other major tumor suppressive pathways in both types of neoplasms.     

双特异性蛋白磷酸酶6在肿瘤中作用的研究进展

双特异性蛋白磷酸酶6（dual specificity phosphatases 6,DUSP6）是一种双特异性蛋白磷酸酶,主要是负反馈调控反转录病毒相关的DNA序列-细胞外信号调节激酶1/2（retrovirus associated DNA sequences-extracellular signal regulated kinase,RAS-ERK1/2）信号通路。而DUSP6对于RAS-ERK1/2信号转导通路的负反馈调节一旦打破,就可能会引起肿瘤,甚至还会出现恶性分化。近年来DUSP6在肿瘤形成、浸润、转移和肿瘤治疗方面的作用,已成为新的研究热点,能有助于许多恶性肿瘤的临床病理的诊断及治疗预后的判断。     

Anti-inflammatory properties of the PI3K pathway are mediated by IL-10/DUSP regulation

Resolution of inflammation is an important hallmark in the course of infectious diseases. Dysregulated inflammatory responses may have detrimental consequences for the affected organism. Therefore, tight regulation of inflammation is indispensable. Among numerous modulatory signaling pathways, the PI3K/PTEN signaling pathway has been proposed recently to be involved in the regulation of innate immune reactions. Here, we attempted to elucidate molecular mechanisms that contribute to the modulatory properties of the PI3K signaling pathway in inflammation. PTEN-deficient macrophages, which harbor constitutively active PI3Ks, were analyzed in response to gram-negative bacteria and PAMPs such as LPS. PTEN-deficient cells showed reduced inflammatory cytokine production, which was accompanied by reduced MAPK signaling activation in early- as well as late-phase activation. Simultaneously, we found increased levels of the MKP DUSP1, as well as the anti-inflammatory cytokine IL-10. Our data suggest that differential DUSP1 regulation coupled with enhanced IL-10 production contributes to the anti-inflammatory properties of the PI3K pathway.     

Metastatic cancer involving pancreatic duct epithelium and its mimicry of primary pancreatic cancer

We investigated 47 autopsy cases of metastatic cancer involving the pancreas. Metastatic disease in nine cases involved the pancreatic duct epithelium. In two cases, metastatic cancer cells showed Pagetoid features. In three cases, pancreatic metastatic disease showed solitary proliferation with focal in situ carcinoma-like lesions mimicking primary pancreatic cancers. Each of these three cases had primary lung adenocarcinomas. Serial sections revealed abrupt borders between the in situ carcinoma-like lesions and the non-cancerous epithelium. Primary pancreatic cancers did not show Pagetoid features or abrupt borders between the cancerous and non-cancerous epithelium. We conclude that the possible diagnosis of pancreatic metastasis should be carefully ruled out in the histological detection of latent primary pancreatic cancer.     

CCL20/CCR6 expression profile in pancreatic cancer

Background  

CCL20 and its receptor CCR6 have been shown to play a role in the onset, development and metastatic spread of various gastrointestinal malignancies. In this study, the expression profile and clinical significance of the CCL20/CCR6 system in distinct benign, pre-malignant and malignant pancreatic tissues was investigated.     

An extensive tumor array analysis supports tumor suppressive role for nucleophosmin in breast cancer

Nucleophosmin (NPM) is a multifunctional protein involved in a complex network of interactions. The role of NPM in oncogenesis is controversial. The NPM gene (NPM1) is mutated or rearranged in a number of hematological disorders, but such changes have not been detected in solid cancers. However, experiments with cultured NPM-null cells and with mice carrying a single inactivated NPM allele indicate a tumor suppressor function for NPM. To resolve the role of NPM in solid cancers, we examined its expression and localization in histologically normal breast tissue and a large array of human breast carcinoma samples (n = 1160), and also evaluated its association with clinicopathological variables and patient survival. The intensity and localization (nucleolar, nuclear, cytoplasmic) of NPM varied across clinical samples. No mutations explaining the differences were found, but the present findings indicate that expression levels of NPM affected its localization. Our study also revealed a novel granular staining pattern for NPM, which was an independent prognostic factor of poor prognosis. In addition, reduced levels of NPM protein were associated with poor prognosis. Furthermore, luminal epithelial cells of histologically normal breast displayed high levels of NPM and overexpression of NPM in the invasive MDA-MB-231 cells abrogated their growth in soft agar. These results support a tumor suppressive role for NPM in breast cancer.     

PI3K/Akt/mTOR信号转导通路与肿瘤

近年来,信号转导通路与肿瘤已成为了研究热点,而无论在生理还是病理条件下磷脂酰肌醇3激酶和哺乳动物雷帕霉素靶蛋白(PI3K/Akt/mTOR)信号转导通路在抑制凋亡、促进增殖方面都是一条重要的信号转导通路,并且PI3 K/Akt/mTOR信号传导通路在肿瘤治疗的研究中同样也发挥着重要作用.因而,研究PI3K/Akt/mTOR信号转导通路和主要组成部分以及PI3K、Akt、mTOR抑制剂具有重要意义.     

马钱子碱通过抑制IL-6/STAT3信号通路诱导结肠癌SW480细胞凋亡

目的:探讨马钱子碱(brucine)在体外对人结肠癌SW480细胞生长和凋亡的影响及可能的分子机制。方法:实验以人结肠癌细胞系SW480细胞为研究对象,分为空白对照组、brucine(1μmol/L)处理组、IL-6(100μg/L)处理组和brucine(1μmol/L)与IL-6(100μg/L)联用组,用CCK-8法检测细胞活力抑制率;流式细胞术Annexin V/PI双染法检测细胞凋亡;Western blot法检测凋亡相关蛋白表达。细胞免疫荧光检测相关蛋白表达定位和强度。结果:Brucine处理组和brucine与IL-6联用组都能抑制结肠癌细胞的活力,brucine浓度相同时,联用组抑制率小于brucine处理组(P0.05)。与空白对照组相比,单用brucine处理组凋亡细胞明显增多(P0.05)。与单用brucine相比,brucine与IL-6联用组凋亡细胞明显减少(P0.05)。与对照组相比,brucine能降低p-STAT3蛋白水平。与空白对照组相比,单用brucine组p-STAT3的蛋白减少,抗凋亡蛋白Bcl-2表达减少,促凋亡蛋白Bax和执行凋亡的cleaved PARP明显增多;与空白对照组相比,单用IL-6处理组的p-STAT3明显增多(P0.05);而与单用brucine相比,brucine与IL-6联合应用组的p-STAT3蛋白增多,抗凋亡蛋白Bcl-2表达增多,促凋亡蛋白Bax和执行凋亡的cleaved PARP均相对减少(P0.05)。结论:体外细胞实验中brucine可能通过调节IL-6/STAT3通路,抑制结肠癌SW480细胞中STAT3的磷酸化激活,从而发挥抗肿瘤作用。     

IL—6信号转导与转录激活子活性研究

目的　探讨 Ｉ Ｌ６ 生物效应与胞内磷酸化蛋白和转录激活子活性变化之间的关系。方法　应用原位杂交和 Ａ Ｐ Ａ Ａ Ｐ 方法检测细胞内 Ｉ Ｌ６ Ｒ ｍ Ｒ Ｎ Ａ 和蛋白的表达;采用 Ｄ Ｎ Ａ 结合蛋白凝胶阻滞电泳分析 Ｉ Ｌ６ 信号转导与 Ａ Ｐ Ｒ Ｆ 活性的相关性;用免疫沉淀和 Ｓ Ｄ Ｓ Ｐ Ａ Ｇ Ｅ 观察 Ｉ Ｌ６ 信号转导中磷酸化蛋白的变化情况。结果　（１） Ｉ Ｌ６ 受体（ Ｉ Ｌ６ Ｒ） ｍ Ｒ Ｎ Ａ 和蛋白表达阳性的人骨髓瘤细胞系（ Ｓ Ｋ Ｏ００７） 体外对 Ｉ Ｌ６ 有增殖反应;（２） 胞内转录激活子活性与 Ｉ Ｌ６ 诱导时间和剂量有相关性,抗ｇｐ１３０ 单克隆抗体和酪氨酸蛋白激酶抑制剂均可特异性抑制转录激活子活性;（３） Ｉ Ｌ６ 诱导 Ｓ Ｋ Ｏ００７细胞后,胞浆内出现一组相对分子质量为（１３０ 、９０ 、５４ 、３６） ×１０３ 磷酸化蛋白,它们的磷酸化活性与转录激活子活性一样,也具有时间和剂量相关性。结论　结果提示,转录激活子和这组相对分子质量不同的酪氨酸磷酸化蛋白参与 Ｉ Ｌ６ 信号转导调节。     

Functional defects in the fanconi anemia pathway in pancreatic cancer cells

Biallelic BRCA2-mutations can cause Fanconi anemia and are found in approximately 7% of pancreatic cancers. Recently, several sequence changes in FANCC and FANCG were reported in pancreatic cancer. Functional defects in the Fanconi pathway can result in a marked hypersensitivity to interstrand crosslinking agents, such as mitomycin C. The functional implications of mutations in the Fanconi pathway in cancer have not been fully studied yet; these studies are needed to pave the way for clinical trials of treatment with crosslinking agents of Fanconi-defective cancers. The competence of the proximal Fanconi pathway was screened in 21 pancreatic cancer cell lines by an assay of Fancd2 monoubiquitination using a Fancd2 immunoblot. The pancreatic cancer cell lines Hs766T and PL11 were defective in Fancd2 monoubiquitination. In PL11, this defect led to the identification of a large homozygous deletion in FANCC, the first cancer cell line found to be FANCC-null. The Fanconi-defective cell lines Hs766T, PL11, and CAPAN1 were hypersensitive to the crosslinking agent mitomycin C and some to cis-platin, as measured by cell survival assays and G(2)/M cell-cycle arrest. These results support the practical exploration of crosslinking agents for non-Fanconi anemia patients that have tumors defective in the Fanconi pathway.     

miR-24-3p靶向KLF6基因调控IL-6/STAT3信号通路影响食管癌细胞的活力和凋亡

目的:探讨微小RNA-24-3p(miR-24-3p)对食管癌细胞活力和凋亡的影响及机制。方法:以人正常食管上皮细胞HEEC为对照,采用RT-qPCR检测食管癌细胞TE11、Eca109和EC9706中miR-24-3p和KLF6 mRNA的表达,Western blot检测KLF6蛋白的表达。用anti-miR-24-3p和KLF6 siRNA转染EC9706细胞,MTT检测细胞活力,流式细胞术检测细胞凋亡率,Western blot检测检测细胞中与增殖、凋亡相关的蛋白以及IL-6/STAT3信号通路相关蛋白的表达,ELISA法检测IL-6的表达。双萤光素酶报告基因实验验证miR-24-3p与KLF6靶向调控的关系。结果:食管癌癌细胞TE11、Eca109和EC9706中miR-24-3p表达上调(P<0.05),KLF6的mRNA和蛋白表达下调(P<0.05)。敲减EC9706细胞miR-24-3p表达可抑制其细胞活力,诱导其凋亡,并抑制细胞CDK4、cyclin D1、CDC25A、p-STAT3、IL-6及Bcl-2的表达,促进caspase-3和Bax的表达。结论...     

ACE、ACE/ACE2对胰腺癌的临床诊断价值初探

目的：探讨血清ACE、ACE2以及其比值对胰腺癌的临床诊断价值。方法：用ELISA方法检测15例胰腺癌患者、10例胰腺癌术后无复发患者、10例单纯CA199升高患者、10例胰腺炎患者及10例健康体检者血清ACE、ACE2、ACE/ACE2的含量,胰腺癌组分别与良性病变组和正常对照组比较。结果：胰腺癌组中ACE、ACE/ACE2分别为(275.340±247.042)、(0.482±0.398) pg/mL,相较胰腺癌术后无复发组、单纯CA199升高组、胰腺炎组和对照组明显升高,差异具有统计学意义(P<0.01)。CA199升高组ACE2水平为(628.343±114.383) pg/mL,明显低于对照组(948.89±496.498) pg/mL(P<0.05)。胰腺炎组ACE2为(515.078±157.815) pg/mL,显著低于对照组。但CA199升高组与胰腺炎组之间无统计学差异(P>0.05)。结论：血清ACE、ACE/ACE2在胰腺癌的诊断中有一定的临床应用价值,可为胰腺癌的诊断提供新的方法。     

Gastroschisis: a gene-environment model involving the VEGF-NOS3 pathway

Gastroschisis is a severe major malformation in which an infant is delivered with a portion of intestines and possible other abdominal organs extruding through a defect in the abdominal wall, usually to the right of the umbilical cord. Etiologies of gastroschisis are largely unknown, and even its pathogenesis is poorly understood. Several recent epidemiological studies have identified interactions between maternal smoking during pregnancy, genetic variants of endothelial nitric oxide synthase, and risk for gastroschisis. We present a brief review of the endothelial nitric oxide synthase pathway and its relationship to vasculogenesis, suggesting that disruption of this pathway by environmental exposures or by genetic variation may represent one pathogenetic model for gastroschisis.     

Geniposide regulates the miR-101/MKP-1/p38 pathway and alleviates atherosclerosis inflammatory injury in ApoE-/- mice

Atherosclerosis (AS) is the common pathological basis of chronic cardiovascular diseases and is associated with inflammation and lipid metabolism dysfunction. Geniposide, the main active ingredient of Gardenia jasminoides Ellis fruit, exhibits a variety of anti-inflammatory and anti-oxidative functions; however, its role in AS remains unclear. The aim of this study was to investigate the mechanisms of geniposide in alleviating inflammation and thereby attenuating the development of AS. ApoE^?/? mice were fed a high fat diet to induce AS and were treated with geniposide (50?mg/kg) for 12 weeks. Blood glucose and lipid levels were measured by biochemical analysis. H&E, Masson and Oil red O staining were performed to observe morphological changes and lipid deposition in the aorta and liver. Serum inflammatory cytokines were detected by ELISA. Dual-luciferase reporter gene assay was used to verify the target relationship between microRNA-101 (miR-101) and mitogen-activated protein kinase phosphatase-1 (MKP-1). The levels of miR-101, p-p38, and MKP-1 in the aorta were detected by qPCR and western blotting. The anti-inflammatory effect of geniposide in vitro was investigated in the RAW264.7 macrophage cell line. A miR-101 mimic and an inhibitor were used to study the effect of miR-101 on regulating the expression of the target MKP-1 and the downstream inflammatory cytokines. Geniposide treatment reduced lipid levels and plaque size in the mouse model of AS. Geniposide downregulated miR-101 to upregulate MKP-1 and suppress the production of inflammatory factors in vitro and in vivo. Geniposide suppressed the levels of inflammatory factors in the presence of the miR-101 mimic, whereas no obvious effect was observed in the miR-101 inhibitor group. We concluded that geniposide reduced the plaque size and alleviated inflammatory injury in ApoE^?/? mice and RAW264.7 cells. The specific anti-inflammatory mechanism was related to the miR-101/ MKP-1/p38 signaling pathway.     

IL-6/STAT3 signaling pathway is activated in plasma cell mastitis

Plasma cell mastitis (PCM), a particular type of mastitis, mainly occurs in females at nonpregnant and nonlactating stages. The infiltration of abundant plasma cells and lymphocytes is the hallmark of the disease. The incidence rate of PCM increased gradually and its pathogenesis remained unclear. In this study, we investigated the expression of IL-6/STAT3 signaling pathway, which is vital not only for the differentiation of plasma cells but also for survival of plasma cells and T lymphocytes, in 30 PCM cases, 10 acute mastitis cases and 10 normal breast tissues by immunohistochemical analysis. IL-6 level was significantly higher in PCM patients than in acute mastitis patients or normal group. The positive rate of IL-6 and p-STAT3 staining in PCM samples was 93.3% (28/30) and 70% (21/30), respectively, and there was a significant positive association between IL-6 and p-STAT3 staining (r=0.408, P=0.025). In PCM group, the rate of nipple retraction was 40% (12/30). Significantly higher IL-6 expression was found in PCM patients with nipple retraction than in other PCM patients. However, no significant difference in IL-6 or p-STAT3 staining was detected between PCM patients experiencing recurrence and other PCM patients. In addition, Bcl-2 level was higher in PCM patients than in acute mastitis patients or normal group, but there was no difference in Bcl-2 immunostaining between PCM patients experiencing recurrence and other PCM patients. These indicate that IL-6/STAT3 signaling is activated in PCM and may play an important role in the pathogenesis of PCM.     

Role of tumor associated macrophages in regulating pancreatic cancer progression

Pancreatic cancer has an overall 5-year survival rate of less than 5%. Unfortunately, patient survival has not substantially improved in the last couple of decades despite advances in treatment modalities that have been successful in other cancer types. The poor response of pancreatic cancer to therapy is a major obstacle faced by clinicians. Increasing attention is being paid to how tumor cells and non-tumor cells influence each other in the pancreatic tumor microenvironment. Tumor-associated macrophages (TAMs) are a highlight in this field because of their vast presence in the tumor microenvironment. TAMs promote angiogenesis, metastasis, and suppress the anti-tumor immune response. Here we review the current understanding of the role of TAMs in regulating the progression of pancreatic cancer.     

泛素-蛋白酶体途径降解胰腺癌细胞系中凝溶胶蛋白

目的 探讨胰腺癌中泛素-蛋白酶体途径对凝溶胶蛋白(gelsolin)的降解作用.方法 用特异性蛋白酶体抑制剂lactacystin处理胰腺癌细胞系BxPC-3和PANC-1,经Westem blot检测凝溶胶蛋白的表达,免疫沉淀细胞内凝溶胶蛋白,分析沉淀蛋白的泛素化.结果 BxPC-3细胞系经lactacystin作用12 h后,细胞内凝溶胶蛋白含量较对照组和处理前明显升高(P＜0.05),而且细胞内的凝溶胶蛋白表现出与泛素分子的相互作用.结论 泛素-蛋白酶体途径对凝溶胶蛋白的降解作用,可能是胰腺癌中凝溶胶蛋白表达降低的原因之一.