The Experts below are selected from a list of 360 Experts worldwide ranked by ideXlab platform
Zhong Jiang - One of the best experts on this subject based on the ideXlab platform.
-
chromosome 12p abnormalities and IMP3 expression in prepubertal pure testicular teratomas
Human Pathology, 2016Co-Authors: Kristine M Cornejo, Mingsheng Wang, Liang Cheng, Alanna J Church, Zhong JiangAbstract:Although the histologic appearance of pure testicular teratomas (PTTs) is similar in children and adults, the prognosis is dramatically different. Prepubertal PTTs are rare, with a benign clinical course, whereas the adult cases typically have malignant outcomes. Chromosome 12p abnormalities are seen in most adult testicular germ cell tumors but have not been found in prepubertal PTTs. IMP3 is an oncofetal protein that is highly expressed in many malignancies. Recently, we demonstrated IMP3 is expressed in adult mature testicular teratomas but not in mature ovarian teratomas. The aim of this study was to evaluate prepubertal PTTs for chromosome 12p abnormalities and expression of IMP3. A total of 11 cases (excision, n=1; orchiectomy, n=10) were obtained from the surgical pathology archives of 2 large medical centers (1957-2013). All 11 cases were investigated for isochromosome 12p and 12p copy number gain using interphase fluorescence in situ hybridization analysis and were examined by immunohistochemistry for IMP3 expression. Patients ranged in age from 0.9 to 7.0 (mean, 2.4) years. A positive immunohistochemical stain for IMP3 (cytoplasmic staining) was identified in 5 (46%) of 11 cases. Isochromosome 12p was detected in 2 cases (18%) that also expressed IMP3. Somatic copy number alterations of 12p were not observed (0%). We are the first to describe 12p abnormalities and IMP3 expression in prepubertal PTTs. Our data demonstrate a small subset of PTTs harbor typical molecular alterations observed in adult testicular germ cell tumors. Although prepubertal PTTs are considered to be benign neoplasms, it may be a heterogeneous group.
-
differential expression of IMP3 between male and female mature teratomas immunohistochemical evidence of malignant nature
Histopathology, 2014Co-Authors: Steven Goodman, Liang Cheng, Liping Zhang, Zhong JiangAbstract:Aims Ovarian mature teratoma is a benign tumour, whereas mature teratoma in adult testicular germ cell tumours (TGCTs) is considered to be a malignant tumour. IMP3, an oncofetal protein, plays an important role in embryogenesis and carcinogenesis. IMP3 has been demonstrated to be a malignant biomarker that is mainly expressed in malignant neoplasms rather than benign tissues. The aim of this study was to analyse IMP3 expression in germ cell tumours, and compare its expression between male and female teratomas. Methods and results One hundred and seventy-eight cases (62 TGCTs, 52 ovarian teratomas, 27 metastatic testicular teratomas, and 37 cases of normal testicular tissue) obtained from the archives of two large academic medical centres were examined for IMP3 expression. Of the 62 TGCTs, 30 had mature teratoma components. IMP3 expression was present in 100% (30/30) of testicular mature teratoma components, and in 96% (26/27) of metastatic testicular teratomas. Other TGCT components also expressed IMP3 in 99% of cases (78/79). IMP3 expression was negative in all female mature teratomas. Conclusions We describe for the first time an immunostaining marker that has differential expression in male and female mature teratomas, indicating that their pathogenesis differs. High expression of IMP3 in adult mature testicular teratomas supports their malignant nature.
-
IMP3 signatures of fallopian tube a risk for pelvic serous cancers
Journal of Hematology & Oncology, 2014Co-Authors: Yiying Wang, Zhong Jiang, Yue Wang, Wenjing Zhang, Guang Yao, Wenxin ZhengAbstract:Background: Recent advances suggest fallopian tube as the main cellular source for women’ sp elvic serous carcinoma (PSC). In addition to TP53 mutations, many other genetic changes are involved in pelvic serous carcinogenesis. IMP3 is an oncofetal protein which has recently been observed to be overexpressed in benign-looking tubal epithelia. Such findings prompted us to examine the relationship between IMP3 over-expression, patient age and the likelihood of development of PSC. Methods: Fallopian tubes from three groups (low-risk, high-risk, and PSC) of patients with matched ages were studied. Age was recorded in 10 years intervals ranging from age 20 to older than 80. The number of IMP3 signatures (defined by 10 or more tubal secretory cells stained positively and continuously in benign appearing tubal mucosa) from both tubal fimbria and ampulla segments was measured. The data was analyzed by standard contingency table and Poisson distribution methods after age adjustment. IMP3 overexpression was also examined in serous tubal intraepithelial carcinoma and PSC. Results: The positive IMP3-stained cells are mainly tubal secretory cells. The absolute number of tubal IMP3 signatures increased significantly within each age group. Age remained a significant risk factor for serous neoplasia after age adjustment. IMP3 signatures were more frequent in the patients of both high-risk and PSC groups. The presence of IMP3 signatures in tubal mucosa was significantly associated with tubal or pelvic serous carcinogenesis (p<0.001). Conclusions: The findings suggest that tubal secretory cells with IMP3 signatures showing growth advantage could potentially serve as a latent precancer biomarker for tubal or pelvic serous carcinomas in women.
-
IMP3 expression is associated with poor outcome and epigenetic deregulation in intrahepatic cholangiocarcinoma
Human Pathology, 2014Co-Authors: Yuanyuan Gao, Zhong Jiang, Bruce A Woda, Michelle X Yang, Arthur M Mercurio, Jianjie Qin, Xinli Huang, Feng ZhangAbstract:IMP3 is a fetal protein not expressed in normal adult tissues. IMP3 is an oncoprotein and a useful biomarker for a variety of malignancies and is associated with reduced overall survival of a number of them. IMP3 expression and its prognostic value for patients with intrahepatic cholangiocarcinoma (ICC) have not been well investigated. The molecular mechanism underlying IMP3 expression in human cancer cells remains to be elucidated. Here we investigated IMP3 expression in ICC and adjacent nonneoplastic liver in 72 unifocal primary ICCs from a single institute by immunohistochemistry, immunoblotting, and real-time polymerase chain reaction. IMP3 was specifically expressed in cancer cells but not in the surrounding normal tissue, and 59 (82%) of 72 ICCs were IMP3 positive by immunohistochemistry. Among 35 cases with lymphovascular invasion, 26 (74%) showed IMP3 positivity in lymph node metastases. IMP3 expression was significantly correlated with tumor size, pathological grade, metastasis, and clinical stage. Kaplan-Meier analysis demonstrated an inverse correlation between IMP3 expression and overall survival rate. Multivariate analysis revealed that IMP3 was the only risk factor associated with survival. To further explore the mechanism of IMP3 expression in cancers, we identified 2 CpG islands at IMP3 proximal promoter. Interestingly, the IMP3 promoter was almost completely demethylated in ICCs in contrast to densely methylated promoter in normal liver tissues. IMP3 expression is a useful biomarker for ICCs and can provide an independent prognostic value for patients with ICC. To our knoweldge, this is the first direct evidence of epigenetic deregulation of IMP3 in human cancer.
-
oncofetal protein IMP3 a new cancer biomarker
Advances in Anatomic Pathology, 2014Co-Authors: Yuna Gong, Bruce A Woda, Zhong JiangAbstract:IMP3 is a member of a family of RNA-binding proteins that consists of IMP1, IMP2 and IMP3. These proteins contain 2 RNA recognition motifs and 4 K-homology domains that allow them to bind RNAs strongly and specifically. IMP3 is an oncofetal protein involved in embryogenesis and its expression is associated with a number of malignant neoplasms. IMP3 is associated with aggressive and advanced cancers and is specifically expressed in malignant tumors but is not found in adjacent benign tissues. Moreover, in vitro studies have shown that IMP3 promotes tumor cell proliferation, adhesion, and invasion. This review focuses on the studies of IMP3 expression in different cancers and emphasizes the potential utility of IMP3 in routine surgical pathology practice. We also discuss IMP3 as a prognostic biomarker for cancer patients' outcomes.
Marcoliver Riener - One of the best experts on this subject based on the ideXlab platform.
-
immunohistochemical expression of IMP3 and p53 in inflammatory lesions and neoplastic lesions of the gastric mucosa
International Journal of Clinical and Experimental Pathology, 2014Co-Authors: Johanna D Strehl, Josef Hoegel, Ines Hornicek, Arndt Hartmann, Marcoliver RienerAbstract:Aim: Expression of the oncofetal protein insulin like growth factor II messenger ribonucleic acid binding protein 3 (IMP3) has been shown to differentiate between benign and malignant lesions in several tissues. Our aim was to assess the immunohistochemical expression of IMP3 in inflammatory and neoplastic lesions of the gastric mucosa and to determine whether IMP3, alone or in combination with p53, could be used for identifying neoplasia of the gastric mucosa. Methods: IMP3 and p53 immunohistochemistry was performed on 57 cases of gastritis, 28 cases of dysplasia of the gastric mucosa and 63 cases of gastric carcinomas. Focal IMP3 positivity was detected in 86% of non-neoplastic lesions of the gastric mucosa. Using a simple product score (PS), 96% of non-neoplastic lesions of the gastric mucosa were assessed as IMP3(PS) negative. None of the low-grade dysplasia but 83% of high-grade dysplasia were IMP3(PS) positive. Gastric carcinomas showed IMP3(PS) positivity in 65%. Adding p53 to the diagnostic panel increased sensitivity significantly. Conclusion: High-grade dysplasia and gastric carcinomas can be distinguished from low-grade dysplasia and inflammatory lesions of the gastric mucosa with a high specificity and good sensitivity using a combination of the immunohistochemical markers IMP3 and p53.
-
insulin like growth factor ii mrna binding protein 3 IMP3 expression in hepatocellular carcinoma a clinicopathological analysis with emphasis on diagnostic value
Histopathology, 2012Co-Authors: David L Wachter, Arndt Hartmann, Florian R Fritzsche, Glen Kristiansen, Christopher Soll, Claus Hellerbrand, Kai Breuhahn, Abbas Agaimy, Marcoliver RienerAbstract:Wachter D L, Kristiansen G, Soll C, Hellerbrand C, Breuhahn K, Fritzsche F, Agaimy A, Hartmann A & Riener M-O (2012) Histopathology 60, 278–286 Insulin-like growth factor II mRNA-binding protein 3 (IMP3) expression in hepatocellular carcinoma. A clinicopathological analysis with emphasis on diagnostic value Aims: Patients with hepatocellular carcinoma (HCC) usually present with advanced disease and rarely qualify for curative therapy. Immunohistochemical markers that help to discriminate benign from malignant processes early, and that have prognostic significance, would be useful. Expression of the oncofetal protein insulin-like growth factor II mRNA-binding protein 3 (IMP3) in malignant cells of different tumour types correlates with reduced overall survival. Methods and results: Tissue microarrays (TMAs) containing 55 normal liver samples, 365 HCCs (122 with corresponding non-tumorous liver), 10 hepatocellular adenomas, 13 focal nodular hyperplasias and nine dysplastic nodules from western European patients were stained for IMP3. IMP3 was analysed in 61 core needle biopsies and findings were compared to glypican-3 and CD34. HCCs in TMAs were strongly positive for IMP3 in 18.4% of cases compared to absent expression in normal and non-tumorous liver tissue and benign liver tumours. Patients with IMP3 expression in HCCs showed significantly poorer overall survival in multivariate analysis (P = 0.044). Of the 61 core needle biopsies analysed, 32 (52.5%) of the HCCs were IMP3-positive. Conclusions: In core needle biopsies, IMP3 expression seems to be of limited use as a single marker for the diagnosis of HCC, given a sensitivity of 52%, but it may be helpful in combination with other markers.
-
diagnostic value of immunohistochemical IMP3 expression in core needle biopsies of pancreatic ductal adenocarcinoma
The American Journal of Surgical Pathology, 2011Co-Authors: David L Wachter, Josef Hoegel, Arndt Hartmann, Glen Kristiansen, Anne Schlabrakowski, Marcoliver RienerAbstract:The oncofetal protein, insulin-like growth factor II messenger ribonucleic acid-binding protein 3 (IMP3), has been analyzed in many different tumors. Various studies have found that IMP3 is a marker for malignancy and is correlated with increased tumor aggressiveness and reduced overall survival. The diagnosis of pancreatic ductal adenocarcinoma (PDAC) in core needle biopsies can be challenging, and immunohistochemical markers are needed. We studied IMP3 expression in 177 core needle biopsies of the pancreas, including 112 PDACs, 55 cases with chronic sclerosing pancreatitis, and 10 biopsies with tumor-free pancreatic tissue without inflammation. An additional 18 biopsies of PDAC metastases (16 liver biopsies and 2 lymph node biopsies) were analyzed. To study IMP3 expression in large tissue sections, 45 pancreatic resection specimens (26 with PDAC and 19 with chronic sclerosing pancreatitis) were investigated. In contrast to normal or inflamed pancreatic tissue, which was negative in 47 of 65 (72.3%) cases and weakly positive in 15 of 65 (23.1%) cases, strong IMP3 expression was found in 99 of 112 (88.4%) PDACs. Therefore, sensitivity and specificity of IMP3 expression in the differential diagnosis of PDAC and chronic sclerosing pancreatitis using core needle biopsies were found to be 88.4% and 94.6%, respectively. These results were confirmed in the pancreas resection specimens. Furthermore, strong IMP3 expression was found in 17 of 18 (94.4%) of the PDAC metastases that were analyzed. Our study shows that IMP3 is an easy to use and potentially new immunohistochemical marker for the diagnosis of PDAC in core needle biopsies.
-
IMP3 expression in lesions of the biliary tract a marker for high grade dysplasia and an independent prognostic factor in bile duct carcinomas
Human Pathology, 2009Co-Authors: Marcoliver Riener, Florian R Fritzsche, Pierrealain Clavien, Bernhard C Pestalozzi, Nicole Probsthensch, Wolfram Jochum, Glen KristiansenAbstract:The oncofetal protein IMP3 (insulin-like growth factor II mRNA binding protein 3) is expressed during embryogenesis and carcinogenesis. Various tumor types have been analyzed for IMP3 expression, which was exclusively found in tumor cells and correlated with increased tumor aggressiveness and reduced overall survival. To our knowledge, IMP3 expression has not been investigated in bile duct carcinomas. Using large tissue sections from resection specimens of the extrahepatic biliary tract, we analyzed IMP3 in normal bile ducts (n = 36), bile ducts with acute inflammation and reactive epithelial changes (n = 26), low-grade dysplasia (n = 9), and high-grade dysplasia (n = 11). Furthermore, IMP3 expression was assessed in bile duct carcinoma (n = 115) using clinically well-characterized tissue microarrays. The findings were correlated with clinical-pathologic parameters including survival. High-grade dysplasia was strongly positive for IMP3 in all cases studied compared with no or weak expression in normal, inflamed, and low-grade dysplastic bile ducts. Of the bile duct carcinomas 58.3% (67/115) were strongly positive for IMP3, which was associated with a higher proliferation rate (P = .004) and p53 positivity (P = .022). Patients with strong IMP3 expression had significantly reduced overall survival (P = .037) similarly to the subgroup of pT3 carcinomas (P = .007). In multivariate analysis, IMP3 expression was an independent prognostic factor for overall survival (P = .040, RR = 1.809). This comprehensive study shows that IMP3 is an independent prognostic biomarker in bile duct carcinoma. In addition, it may be a marker for high-grade dysplasia in the extrahepatic biliary tract.
Bruce A Woda - One of the best experts on this subject based on the ideXlab platform.
-
IMP3 expression is associated with poor outcome and epigenetic deregulation in intrahepatic cholangiocarcinoma
Human Pathology, 2014Co-Authors: Yuanyuan Gao, Zhong Jiang, Bruce A Woda, Michelle X Yang, Arthur M Mercurio, Jianjie Qin, Xinli Huang, Feng ZhangAbstract:IMP3 is a fetal protein not expressed in normal adult tissues. IMP3 is an oncoprotein and a useful biomarker for a variety of malignancies and is associated with reduced overall survival of a number of them. IMP3 expression and its prognostic value for patients with intrahepatic cholangiocarcinoma (ICC) have not been well investigated. The molecular mechanism underlying IMP3 expression in human cancer cells remains to be elucidated. Here we investigated IMP3 expression in ICC and adjacent nonneoplastic liver in 72 unifocal primary ICCs from a single institute by immunohistochemistry, immunoblotting, and real-time polymerase chain reaction. IMP3 was specifically expressed in cancer cells but not in the surrounding normal tissue, and 59 (82%) of 72 ICCs were IMP3 positive by immunohistochemistry. Among 35 cases with lymphovascular invasion, 26 (74%) showed IMP3 positivity in lymph node metastases. IMP3 expression was significantly correlated with tumor size, pathological grade, metastasis, and clinical stage. Kaplan-Meier analysis demonstrated an inverse correlation between IMP3 expression and overall survival rate. Multivariate analysis revealed that IMP3 was the only risk factor associated with survival. To further explore the mechanism of IMP3 expression in cancers, we identified 2 CpG islands at IMP3 proximal promoter. Interestingly, the IMP3 promoter was almost completely demethylated in ICCs in contrast to densely methylated promoter in normal liver tissues. IMP3 expression is a useful biomarker for ICCs and can provide an independent prognostic value for patients with ICC. To our knoweldge, this is the first direct evidence of epigenetic deregulation of IMP3 in human cancer.
-
oncofetal protein IMP3 a new cancer biomarker
Advances in Anatomic Pathology, 2014Co-Authors: Yuna Gong, Bruce A Woda, Zhong JiangAbstract:IMP3 is a member of a family of RNA-binding proteins that consists of IMP1, IMP2 and IMP3. These proteins contain 2 RNA recognition motifs and 4 K-homology domains that allow them to bind RNAs strongly and specifically. IMP3 is an oncofetal protein involved in embryogenesis and its expression is associated with a number of malignant neoplasms. IMP3 is associated with aggressive and advanced cancers and is specifically expressed in malignant tumors but is not found in adjacent benign tissues. Moreover, in vitro studies have shown that IMP3 promotes tumor cell proliferation, adhesion, and invasion. This review focuses on the studies of IMP3 expression in different cancers and emphasizes the potential utility of IMP3 in routine surgical pathology practice. We also discuss IMP3 as a prognostic biomarker for cancer patients' outcomes.
-
IMP3 a new biomarker to predict progression of cervical intraepithelial neoplasia into invasive cancer
The American Journal of Surgical Pathology, 2011Co-Authors: Xiaofang Yang, Bruce A Woda, Kenneth L Rock, Arthur M Mercurio, Karen Dresser, Naomi Y Jiang, Qin Liu, Zhong JiangAbstract:The expression of IMP3, an oncofetal protein, has been strongly associated with aggressive cancers. In this study, we investigated whether IMP3 can serve as a biomarker to predict invasive squamous cell carcinoma (SCC) in patients with cervical intraepithelial neoplasia (CIN) II and III. A total of 1249 patients with no dysplasia, CINs, or invasive SCC were studied for IMP3 expression. The 710 patients with CIN II and III in their cervical biopsies were further evaluated for invasive cancer-free survival analysis. The role of IMP3 in the regulation of cell proliferation and migration of HeLa cervical cancer cells was examined by modification of IMP3 expression with small interference RNA. Compared with CIN I or cervical tissues without dysplasia, IMP3 expression was significantly increased not only in invasive SCC but also most importantly in a subset of CIN III cases with concurrent invasive SCC. Importantly, invasive cancer was found only in patients with IMP3-positive CIN II and III, whereas no invasive cancer was detected in patients with IMP3-negative CIN II and III in their follow-up resections (P<0.0001). Reduction of IMP3 expression in cervical cancer cells significantly reduced cell migration without altering cell proliferation. IMP3 plays a critical role in the development of invasive SCC from cervical dysplasia. IMP3 can be used at the time of initial diagnosis of CIN to identify a group of patients with an increased chance of developing invasive cancer.
-
oncofetal protein IMP3 a new diagnostic biomarker to distinguish malignant mesothelioma from reactive mesothelial proliferation
The American Journal of Surgical Pathology, 2011Co-Authors: Min Shi, Kristine M Cornejo, Bruce A Woda, Kenneth L Rock, Armando E Fraire, Peiguo Chu, Karen Dresser, Zhong JiangAbstract:The distinction of malignant mesothelioma from reactive mesothelial proliferation remains to be a major challenge for surgical pathologists. In this study, we investigated whether insulin-like growth factor II messenger ribonucleic acid-binding protein 3 (IMP3), an oncofetal protein, can be used as a biomarker to distinguish between malignant and reactive mesothelial cells. A total of 109 cases (mesothelioma, n=45; reactive mesothelial proliferation, n=64) were examined by immunohistochemistry for IMP3 expression. IMP3 showed strong cytoplasmic staining in 33 of 45 (73%) mesothelioma cases. In contrast, the expression of IMP3 was undetectable in all (64 cases) benign reactive mesothelial proliferations. Among the IMP3-positive mesotheliomas, 27 (82%) exhibited diffuse IMP3 expression. The vast majority of IMP3-positive subtypes of mesotheliomas showed IMP3 expression in >50% of malignant cells, as this diffuse staining pattern occurred in 17 (81%) cases of epithelial, 4 (100%) cases of sarcomatoid, and 6 (75%) cases of mixed types of mesothelioma. In addition, 2 cases, which were initially diagnosed as atypical mesothelial proliferations and later confirmed to be mesotheliomas, showed diffuse IMP3 expression. Our findings suggest that IMP3 is a new positive biomarker for malignant mesothelioma. IMP3 immunohistochemical staining can be used as an adjunct tool in the distinction of malignant mesothelioma from reactive mesothelial proliferations.
-
an oncofetal protein IMP3 a new molecular marker for the detection of esophageal adenocarcinoma and high grade dysplasia
The American Journal of Surgical Pathology, 2009Co-Authors: Poonam Vohra, Peigou G Chu, Bruce A Woda, Kenneth L Rock, Zhong JiangAbstract:Accurate diagnosis of dysplasia and adenocarcinoma in patients with Barrett esophagus is critical for clinical decision-making and patient management. IMP3 is an oncofetal protein and has been demonstrated to be associated with aggressive tumor behavior. The aim of this study was to establish the expression pattern and diagnostic value of IMP3 in Barrett esophagus, dysplasia, and carcinoma. A total of 217 cases (resection, n=56; biopsy, n=161) with 302 lesions (invasive esophageal adenocarcinoma, n=147; metastatic esophageal adenocarcinoma, n=14; high-grade dysplasia of the esophagus, n=52; low-grade dysplasia of the esophagus gland, n=21; and Barrett esophagus, n=68) were examined by immunohistochemistry for IMP3 expression. IMP3 showed strong cytoplasmic granular staining in 138 of 147 (94%) of invasive esophageal adenocarcinomas, 13 of 14 (93%) of metastatic esophageal adenocarcinomas, and 49 of 52 (94%) of high-grade dysplasias. In contrast, 3/21 (14%) of low-grade dysplasia and 5/68 (7%) Barrett esophagus were positive for IMP3. Expression of IMP3 was not found in adjacent benign squamous and glandular mucosa. Our findings indicate that IMP3 is a highly sensitive and specific biomarker for the diagnosis of invasive esophageal adenocarcinoma and high-grade dysplasia. The data also suggest that IMP3, an oncofetal protein, may play an important role in malignant transformation in esophageal adenocarcinoma.
Alan Cochrane - One of the best experts on this subject based on the ideXlab platform.
-
interaction of human immunodeficiency virus type 1 integrase with cellular nuclear import receptor importin 7 and its impact on viral replication
Journal of Biological Chemistry, 2007Co-Authors: Zhujun Ao, Guanyou Huang, Zaikun Xu, Meaghan Labine, Alan CochraneAbstract:Next Section Abstract Similar to all other viruses, human immunodeficiency virus type 1 (HIV-1) depends heavily on cellular factors for its successful replication. In this study we have investigated the interaction of HIV-1 integrase (IN) with several host nuclear import factors using co-immunoprecipitation assays. Our results indicate that IN interacts specifically with host importin 7 (Imp7) in vivo, but does not interact with importin 8 (Imp8) or importin α (Rch1). In contrast, another HIV-1 karyophilic protein MAp17, which is capable of binding Rch1, fails to interact with Imp7, suggesting that IN and Map17 may interact with different cellular pathways during HIV-1 replication. Genetic analysis revealed that the C-terminal domain of IN is the region responsible for interaction between IN with Imp7, and an IN mutant (K240A,K244A/R263A,K264A) disrupted the Imp7 binding ability of the protein, indicating that both regions (235WKGPAKLLWKG and 262RRKAK) within the C-terminal domain of IN are required for efficient IN/Imp7 interaction. Using a vesicular stomatitis virus G glycoprotein pseudotyped HIV single-cycle replication system, we showed that the IN/Imp7 interaction-deficient mutant was unable to mediate viral replication and displayed impairment at both viral reverse transcription and nuclear import steps. Moreover, transient knockdown of Imp7 in both HIV-1 producing and target cells resulted in a 2.5–3.5-fold inhibition of HIV infection. Altogether, our results indicate that HIV-1 IN specifically interacts with Imp7, and this viral/cellular protein interaction contributes to efficient HIV-1 infection.
-
interaction of human immunodeficiency virus type 1 integrase with cellular nuclear import receptor importin 7 and its impact on viral replication
Journal of Biological Chemistry, 2007Co-Authors: Guanyou Huang, Meaghan Labine, Alan Cochrane, Han Yao, Xiaojian YaoAbstract:Similar to all other viruses, human immunodeficiency virus type 1 (HIV-1) depends heavily on cellular factors for its successful replication. In this study we have investigated the interaction of HIV-1 integrase (IN) with several host nuclear import factors using co-immunoprecipitation assays. Our results indicate that IN interacts specifically with host importin 7 (Imp7) in vivo, but does not interact with importin 8 (Imp8) or importin alpha (Rch1). In contrast, another HIV-1 karyophilic protein MAp17, which is capable of binding Rch1, fails to interact with Imp7, suggesting that IN and Map17 may interact with different cellular pathways during HIV-1 replication. Genetic analysis revealed that the C-terminal domain of IN is the region responsible for interaction between IN with Imp7, and an IN mutant (K240A,K244A/R263A,K264A) disrupted the Imp7 binding ability of the protein, indicating that both regions ((235)WKGPAKLLWKG and (262)RRKAK) within the C-terminal domain of IN are required for efficient IN/Imp7 interaction. Using a vesicular stomatitis virus G glycoprotein pseudotyped HIV single-cycle replication system, we showed that the IN/Imp7 interaction-deficient mutant was unable to mediate viral replication and displayed impairment at both viral reverse transcription and nuclear import steps. Moreover, transient knockdown of Imp7 in both HIV-1 producing and target cells resulted in a 2.5-3.5-fold inhibition of HIV infection. Altogether, our results indicate that HIV-1 IN specifically interacts with Imp7, and this viral/cellular protein interaction contributes to efficient HIV-1 infection.
Arthur M Mercurio - One of the best experts on this subject based on the ideXlab platform.
-
IMP3 stabilization of wnt5b mrna facilitates taz activation in breast cancer
Cell Reports, 2018Co-Authors: Sanjoy Samanta, Santosh Guru, Ameer L Elaimy, John J Amante, Lihua Julie Zhu, Arthur M MercurioAbstract:Summary Insulin-like growth factor-2 mRNA-binding protein 3 (IMP3) is an oncofetal protein associated with many aggressive cancers and implicated in the function of breast cancer stem cells (CSCs). The mechanisms involved, however, are poorly understood. We observed that IMP3 facilitates the activation of TAZ, a transcriptional co-activator of Hippo signaling that is necessary for the function of breast CSCs. The mechanism by which IMP3 activates TAZ involves both mRNA stability and transcriptional regulation. IMP3 stabilizes the mRNA of an alternative WNT ligand (WNT5B) indirectly by repressing miR145-5p, which targets WNT5B, resulting in TAZ activation by alternative WNT signaling. IMP3 also facilitates the transcription of SLUG, which is necessary for TAZ nuclear localization and activation, by a mechanism that is also mediated by WNT5B. These results demonstrate that TAZ can be regulated by an mRNA-binding protein and that this regulation involves the integration of Hippo and alternative WNT-signaling pathways.
-
IMP3 expression is associated with poor outcome and epigenetic deregulation in intrahepatic cholangiocarcinoma
Human Pathology, 2014Co-Authors: Yuanyuan Gao, Zhong Jiang, Bruce A Woda, Michelle X Yang, Arthur M Mercurio, Jianjie Qin, Xinli Huang, Feng ZhangAbstract:IMP3 is a fetal protein not expressed in normal adult tissues. IMP3 is an oncoprotein and a useful biomarker for a variety of malignancies and is associated with reduced overall survival of a number of them. IMP3 expression and its prognostic value for patients with intrahepatic cholangiocarcinoma (ICC) have not been well investigated. The molecular mechanism underlying IMP3 expression in human cancer cells remains to be elucidated. Here we investigated IMP3 expression in ICC and adjacent nonneoplastic liver in 72 unifocal primary ICCs from a single institute by immunohistochemistry, immunoblotting, and real-time polymerase chain reaction. IMP3 was specifically expressed in cancer cells but not in the surrounding normal tissue, and 59 (82%) of 72 ICCs were IMP3 positive by immunohistochemistry. Among 35 cases with lymphovascular invasion, 26 (74%) showed IMP3 positivity in lymph node metastases. IMP3 expression was significantly correlated with tumor size, pathological grade, metastasis, and clinical stage. Kaplan-Meier analysis demonstrated an inverse correlation between IMP3 expression and overall survival rate. Multivariate analysis revealed that IMP3 was the only risk factor associated with survival. To further explore the mechanism of IMP3 expression in cancers, we identified 2 CpG islands at IMP3 proximal promoter. Interestingly, the IMP3 promoter was almost completely demethylated in ICCs in contrast to densely methylated promoter in normal liver tissues. IMP3 expression is a useful biomarker for ICCs and can provide an independent prognostic value for patients with ICC. To our knoweldge, this is the first direct evidence of epigenetic deregulation of IMP3 in human cancer.
-
IMP3 protein promotes chemoresistance in breast cancer cells by regulating breast cancer resistance protein abcg2 expression
Journal of Biological Chemistry, 2013Co-Authors: Sanjoy Samanta, Bryan M Pursell, Arthur M MercurioAbstract:IMP3, a member of a family of insulin-like growth factor II (IGF-II) mRNA-binding proteins (IMPs), is expressed preferentially in triple-negative breast cancers, which are resistant to many chemotherapeutics. However, the mechanisms by which it impacts breast cancer have not been elucidated. We hypothesized a role for IMP3 in chemoresistance based on these observations. Depletion of IMP3 expression in triple-negative breast cancer cells increased their sensitivity to doxorubicin and mitoxantrone significantly but not to taxol. Given that doxorubicin and mitoxantrone are effluxed by breast cancer resistance protein (BCRP), we assessed whether IMP3 regulates BCRP. The data obtained demonstrate that IMP3 binds to BCRP mRNA and regulates BCRP expression. These findings are significant because they provide insight into the mechanism by which IMP3 contributes to aggressive cancers, and they highlight the potential for targeting this mRNA-binding protein for the clinical management of cancer.
-
regulation of IMP3 by egfr signaling and repression by erβ implications for triple negative breast cancer
Oncogene, 2012Co-Authors: Sanjoy Samanta, Ashraf Khan, Vishva Mitra Sharma, Arthur M MercurioAbstract:Insulin-like growth factor II (IGF-II) mRNA-binding protein 3 (IMP3) is emerging as a useful indicator of the progression and outcome of several cancers. IMP3 expression is associated with triple-negative breast carcinomas (TNBCs), which are aggressive tumors associated with poor outcome. In this study, we addressed the hypothesis that signaling pathways, which are characteristic of TNBCs, impact the expression of IMP3 and that IMP3 contributes to the function of TNBCs. The data obtained reveal that IMP3 expression is repressed specifically by estrogen receptor β (ERβ) and its ligand 3βA-diol but not by ERα. Epidermal growth factor receptor (EGFR) signaling and consequent activation of the mitogen-activated protein kinase pathway induce IMP3 transcription and expression. Interestingly, we discovered that the EGFR promoter contains an imperfect estrogen response element and that ERβ represses EGFR transcription. These data support a mechanism in which ERβ inhibits IMP3 expression indirectly by repressing the EGFR. This mechanism relates to the biology of TNBC, which is characterized by diminished ERβ and increased EGFR expression. We also demonstrate that IMP3 contributes to the migration and invasion of breast carcinoma cells. Given that IMP3 is an mRNA-binding protein, we determined that it binds several key mRNAs that could contribute to migration and invasion, including CD164 (endolyn) and MMP9. Moreover, expression of these mRNAs is repressed by ERβ and enhanced by EGFR signaling, consistent with our proposed mechanism for the regulation of IMP3 expression in breast cancer cells. Our findings show that IMP3 is an effector of EGFR-mediated migration and invasion and they provide the first indication of how this important mRNA-binding protein is regulated in cancer.
-
IMP3 a new biomarker to predict progression of cervical intraepithelial neoplasia into invasive cancer
The American Journal of Surgical Pathology, 2011Co-Authors: Xiaofang Yang, Bruce A Woda, Kenneth L Rock, Arthur M Mercurio, Karen Dresser, Naomi Y Jiang, Qin Liu, Zhong JiangAbstract:The expression of IMP3, an oncofetal protein, has been strongly associated with aggressive cancers. In this study, we investigated whether IMP3 can serve as a biomarker to predict invasive squamous cell carcinoma (SCC) in patients with cervical intraepithelial neoplasia (CIN) II and III. A total of 1249 patients with no dysplasia, CINs, or invasive SCC were studied for IMP3 expression. The 710 patients with CIN II and III in their cervical biopsies were further evaluated for invasive cancer-free survival analysis. The role of IMP3 in the regulation of cell proliferation and migration of HeLa cervical cancer cells was examined by modification of IMP3 expression with small interference RNA. Compared with CIN I or cervical tissues without dysplasia, IMP3 expression was significantly increased not only in invasive SCC but also most importantly in a subset of CIN III cases with concurrent invasive SCC. Importantly, invasive cancer was found only in patients with IMP3-positive CIN II and III, whereas no invasive cancer was detected in patients with IMP3-negative CIN II and III in their follow-up resections (P<0.0001). Reduction of IMP3 expression in cervical cancer cells significantly reduced cell migration without altering cell proliferation. IMP3 plays a critical role in the development of invasive SCC from cervical dysplasia. IMP3 can be used at the time of initial diagnosis of CIN to identify a group of patients with an increased chance of developing invasive cancer.
