Oncofetal Protein Research Articles

Oncofetal protein IMP3: a new diagnostic biomarker for laryngeal carcinoma

An accurate diagnosis of laryngeal squamous cell carcinoma (LSCC) is essential for patient management. The diagnosis of LSCC, especially in superficial biopsies, can present a diagnostic challenge for pathologists. The ability to diagnose LSCC would be greatly improved by the detection of a tumor-associated antigen. IMP3 is an oncofetal protein associated with aggressive and advanced tumors and is specifically expressed in malignant tumors but not found in benign tissues. The aim of this study was to determine the expression and diagnostic value of IMP3 in LSCC to determine whether it can serve as a diagnostic biomarker. A total of 238 cases (laryngectomy, n = 121; biopsy, n = 117) consisting of 11 laryngeal carcinoma in situ/severe dysplasia and 227 invasive LSCC were examined by immunohistochemistry for IMP3 expression. IMP3 showed strong cytoplasmic staining in 217 (92%) of 238 LSCCs regardless of histologic grade. In addition, 58 (89%) of 65 small biopsies (≤5 mm in greatest dimension) containing a minute amount of carcinoma were positive for IMP3. In contrast to malignant tumors, IMP3 expression was not found in any of the adjacent benign squamous epithelium (0/118 cases; 0%), mild or moderate dysplasia (0/139 cases; 0%), or pseudoepitheliomatous hyperplasia (0/99 cases; 0%). In summary, we are the first to describe that IMP3 is a highly sensitive and specific biomarker for LSCC. The expression of IMP3 in LSCC can be used as a positive biomarker to increase the level of confidence in establishing a definitive diagnosis of a malignancy in laryngeal biopsy.

Oncofetal Gene SALL4 in Aggressive Hepatocellular Carcinoma

BackgroundHepatocellular carcinoma is the third leading cause of cancer-related deaths worldwide. In the heterogeneous group of hepatocellular carcinomas, those with characteristics of embryonic stem-cell and progenitor-cell gene expression are associated with the worst prognosis. The oncofetal gene SALL4, a marker of a subtype of hepatocellular carcinoma with progenitor-like features, is associated with a poor prognosis and is a potential target for treatment.MethodsWe screened specimens obtained from patients with primary hepatocellular carcinoma for the expression of SALL4 and carried out a clinicopathological analysis. Loss-of-function studies were then performed to evaluate the role of SALL4 in hepatocarcinogenesis and its potential as a molecular target for therapy. To assess the therapeutic effects of a peptide that targets SALL4, we used in vitro functional and in vivo xenograft assays.ResultsSALL4 is an oncofetal protein that is expressed in the human fetal liver and silenced in the adult liver, but it is reexpressed in a subgroup of patients who have hepatocellular carcinoma and an unfavorable prognosis. Gene-expression analysis showed the enrichment of progenitor-like gene signatures with overexpression of proliferative and metastatic genes in SALL4-positive hepatocellular carcinomas. Loss-of-function studies confirmed the critical role of SALL4 in cell survival and tumorigenicity. Blocking SALL4–corepressor interactions released suppression of PTEN (the phosphatase and tensin homologue protein) and inhibited tumor formation in xenograft models in vivo.ConclusionsSALL4 is a marker for a progenitor subclass of hepatocellular carcinoma with an aggressive phenotype. The absence of SALL4 expression in the healthy adult liver enhances the potential of SALL4 as a treatment target in hepatocellular carcinoma. (Funded by the Singapore National Medical Research Council and others.)

IGF2BP1 promotes mesenchymal cell properties and migration of tumor-derived cells by enhancing the expression of LEF1 and SNAI2 (SLUG)

The oncofetal IGF2 mRNA-binding protein 1 (IGF2BP1) controls the migration and invasiveness of primary as well as tumor-derived cells in vitro. Whether the protein also modulates epithelial-mesenchymal-transition (EMT), a hallmark of tumor progression involved in tumor cell dissemination, remained elusive. In this study, we reveal that IGF2BP1 enhances mesenchymal-like cell properties in tumor-derived cells by promoting the expression of the transcriptional regulators LEF1 and SLUG (SNAI2). IGF2BP1 associates with LEF1 transcripts and prevents their degradation in a 3′-UTR-dependent manner resulting in an upregulation of LEF1 expression. LEF1 promotes transcription of the mesenchymal marker fibronectin by associating with the fibronectin 1 promoter. Moreover, LEF1 enforces the synthesis of the ‘EMT-driving’ transcriptional regulator SNAI2. Accordingly, IGF2BP1 knockdown causes MET-like (mesenchymal-epithelial-transition) morphological changes, enhances the formation of cell–cell contacts and reduces cell migration in various mesenchymal-like tumor-derived cells. However, in epithelial-like tumor-derived cells characterized by a lack or low abundance of IGF2BP1, the protein fails to induce EMT. These findings identify IGF2BP1 as a pro-mesenchymal post-transcriptional determinant, which sustains the synthesis of ‘EMT-driving’ transcriptional regulators, mesenchymal markers and enhances tumor cell motility. This supports previous reports, suggesting a role of IGF2BP1 in tumor cell dissemination.

Glypican-3 is a potential prognostic biomarker for hepatocellular carcinoma after curative resection

Glypican-3 (GPC3), an oncofetal protein, is overexpressed in hepatocellular carcinoma (HCC). The diagnostic efficacy of GPC3 for HCC has been evaluated intensively in recent years; however, the prognostic value of GPC3 for HCC has not been well clarified. The purpose of this study was to investigate the relationship between GPC3 and postoperative patient survival in a prospective database. GPC3 protein was detected by immunohistochemistry. The relationship between GPC3 expression level and patients' clinicopathologic factors was analyzed. Kaplan-Meier survival analysis was used to calculate patients' survival and was compared by using the log rank test. The Cox regression model was used to identify the risk factors associated with prognosis. GPC3 was expressed in 84% of HCC tissues. GPC3 protein expression was correlated with thenumber of tumors (P = .015), serum alpha-fetoprotein (AFP) level (P = .011), and TNM stage (P=.006). High GPC3 expression was an independent risk factor for poor postoperative disease-free survival (hazard ratio [HR] = 0.469; 95% confidence interval [CI] 0.303-0.727; P = .001); and overall survival (HR = 0.435; 95% CI, 0.257-0.736; P = .002). Stratification analysis indicated that GPC3 had a good predictive value for tumor recurrence in patients with HCC who have normal serum AFP levels. Also, GPC3 expression status could predict the outcomes of patients with stage I disease. GPC3 is a potential and reliable biomarker for predicting tumor recurrence and overall survival in HCC patients after curative resection.

Abstract 3008: IGF2 mRNA binding protein 1 drives growth, metastasis and chemoresistance in osteosarcoma.

Abstract Osteosarcoma (OSA) is the most common bone tumor in children arising in the metaphyseal regions of the appendicular skeleton and frequently metastasizing to the lungs. Standard treatment for OSA of surgical resection with neoadjuvant and adjuvant chemotherapy using multi-agent dose intensive therapy has resulted in survival rates of 75%, however for patients with metastasis at diagnosis, the survival rate is only 20%. Consequently, increased understanding of the mechanisms that contribute to metastasis and resistance to therapy is needed. Unfortunately, the availability of OSA samples for study is extremely limited. However, over 10,000 canine patients spontaneously develop OSA annually and canine tumors share common histological features, genetic mutations and gene expression profiles with human OSA. To identify factors that contribute to metastasis and chemotherapeutic resistance of OSA, we assessed the gene expression signatures of normal bone and groups of primary canine OSA tumors surgically resected from dogs with short and long disease free intervals (DFI) following standard treatment of amputation and therapy with doxorubicin or platinum-based drugs. Since the average DFI following treatment in canine osteosarcoma is approximately 200 days, these groups included tumors from dogs with DFI<100 days and DFI>300 days. We identified IGF2 mRNA binding protein 1 (IGF2BP1) as a gene with elevated expression in osteosarcomas from patients with a DFI<100 days compared to the DFI>300 group (7-fold, p=0.047) and normal bone (920-fold, p<0.001). IGF2BP1 is an oncofetal protein that binds multiple mRNA targets to regulate their nuclear transport, stability, translation and subcellular localization. In five human OSA cell lines we measured an average 14-fold increase in IGF2BP1 mRNA transcripts compared to normal human osteoblasts. More importantly, we measured elevated mRNA transcripts (five-fold, p=0.0368) and protein levels (seven-fold) in the MG63.2 cell line, a metastatic variant of the MG63 human OSA cell line, implicating IGF2BP1 in metastasis of osteosarcoma. IGF2BP1 knockdown in shRNA-expressing MG63.2 clones reduced cell invasion by 42% (p<0.05). In addition, IGF2BP1 knockdown in MG63.2 cells resulted in a three-fold (p<0.001) decrease in cellular proliferation compared to cells stably expressing a non-targeted shRNA construct. A similar experiment was performed in vivo using a subcutaneous model in nude mice (n=5/group) where the IGF2BP1 knockdown tumors from two independent shRNA constructs displayed significantly delayed tumor appearance and reduced tumor volume compared to control at days 9 (p<0.05), 12 and 14 (p<0.001) following tumor cell inoculation. Finally, IGF2BP1 knockdown resulted in a two-fold increase in doxorubicin sensitivity in MG63.2 cells (95% confidence interval). Overall, these data suggest IGF2BP1 drives OSA growth, metastasis and chemotherapeutic resistance. Citation Format: Brian T. Kalet, Liza E. O'Donoghue, Dawn L. Duval. IGF2 mRNA binding protein 1 drives growth, metastasis and chemoresistance in osteosarcoma. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 3008. doi:10.1158/1538-7445.AM2013-3008

Abstract 827: Identification of the insulin-like growth factor 2 mRNA binding protein (IGF2BP1) as an important regulator of cIAP1 translation and apoptosis in rhabdomyosarcomas.

Abstract Rhabdomyosarcoma, a neoplasm characterized by undifferentiated myoblats-like cells, is the most common soft tissue sarcoma of childhood and represents 3-4% of all childhood cancers. IGF2BP1 is an oncofetal protein that was first identified in the rhabdomyosarcoma RD cell line and was shown to be overexpressed in a variety of cancers. Our group has previously identified IGF2BP1 as a potential translation modulator of the cellular inhibitor of apoptosis protein 1 (cIAP1), a key regulator of the NFκB signaling pathway and of caspase-8 mediated cell death in mammalian cells. In this study, we report that IGF2BP1 and cIAP1 expression is upregulated in a panel of rhabdomyosarcoma cell lines. We also show that IGF2BP1 is a positive regulator of cIAP1 translation, specifically through an internal ribosome entry site (IRES) mechanism. Finally, we report that altering the levels of cIAP1 in two rhabdomyosarcoma cell lines, RH36 and RH41, either by IGF2BP1 knock-down or by a Smac mimetic coumpound, sensitizes these cells to TNFα-mediated cell death. Our results identify IGF2BP1 and cIAP1 as important regulators of apoptosis in rhabdomyosarcomas. Citation Format: Mame Daro Faye, Tyson Graber, Stephanie Langlois, Kyle Cowan, Martin Holcik. Identification of the insulin-like growth factor 2 mRNA binding protein (IGF2BP1) as an important regulator of cIAP1 translation and apoptosis in rhabdomyosarcomas. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 827. doi:10.1158/1538-7445.AM2013-827

Alkaline Phosphatase ALPPL-2 Is a Novel Pancreatic Carcinoma-Associated Protein

Pancreatic ductal adenocarcinoma (PDAC) is a highly aggressive malignancy with a very low median survival rate. The lack of early sensitive diagnostic markers is one of the main causes of PDAC-associated lethality. Therefore, to identify novel pancreatic cancer biomarkers that can facilitate early diagnosis and also help in the development of effective therapeutics, we developed RNA aptamers targeting pancreatic cancer by Cell-systematic evolution of ligands by exponential enrichment (SELEX) approach. Using a selection strategy that could generate aptamers for 2 pancreatic cancer cell lines in one selection scheme, we identified an aptamer SQ-2 that could recognize pancreatic cancer cells with high specificity. Next, by applying 2 alternative approaches: (i) aptamer-based target pull-down and (ii) genome-wide microarray-based identification of differentially expressed mRNAs in aptamer-positive and -negative cells, we identified alkaline phosphatase placental-like 2 (ALPPL-2), an oncofetal protein, as the target of SQ-2. ALPPL-2 was found to be ectopically expressed in many pancreatic cancer cell lines at both mRNA and protein levels. RNA interference-mediated ALPPL-2 knockdown identified novel tumor-associated functions of this protein in pancreatic cancer cell growth and invasion. In addition, the aptamer-mediated identification of ALPPL-2 on the cell surface and cell secretions of pancreatic cancer cells supports its potential use in the serum- and membrane-based diagnosis of PDAC.

Glycoprotein 96 and α-Fetoprotein Cross-Linking Complexes Elicited Specific Antitumor Immunity

Hepatocellular carcinoma (HCC) is one of the most common malignant gastroenterological cancers over the world. α-fetoprotein (AFP) is an oncofetal protein produced during HCC development that could generate weaker and less reproducible antitumor protection, and it may serve as a target for immunotherapy. Therefore, it is imperative to enhance its immunogenicity and develop therapeutic vaccines to eliminate AFP-expressing tumors. In this study, by way of glutaraldehyde cross-linking, we constructed a potential therapeutic protein vaccine, glycoprotein 96 (gp96)/AFP. Our results demonstrated that AFP and gp96 synergistically exhibited significant increase in AFP-specific CD8⁺ T-cell responses and impressive cytotoxic antitumor effect against AFP-expressing tumors. Priming mice with the reconstructed vaccine, we elicited robust strong protective immunity. Our study suggests that tumor vaccine by cross-linking tumor antigen and gp96 is a promising approach to cancer therapy.

The oncofetal protein IMP3: a novel biomarker and triage tool for premalignant atypical endometriotic lesions

To determine whether the oncofetal protein IMP3 is detectable in endometriomas with or without histological atypia and whether IMP3 staining can be used as a triage tool to identify foci of atypical endometriosis in doubtful cases. Retrospective study. Academic department and referral center for endometriosis. A consecutive series of 516 women who underwent excision of 874 endometriomas. Histological review by three expert pathologists and immunohistochemical staining for IMP3. Test performance of IMP3 immunohistochemistry versus first-round histology. The prevalence of atypical endometriosis was 1.7% (95% confidence interval [CI], 0.9%-3.3%) based on the number of women and 1.0% (95% CI, 0.5%-1.9%) based on the number of cysts. Three cases of atypical endometriosis were identified at first-round histological examination. Immunohistochemistry detected seven of the eight cases diagnosed as preneoplastic atypia at second-round histology and one case diagnosed as reactive atypia at second-round histology. The sensitivity of first-round histology was 33.3%, compared with 88.9% of IMP3 immunohistochemistry. Immunohistochemical staining for IMP3 expression is a simple, inexpensive, and sensitive test that can be used in routine clinical practice as a triage tool to discriminate between cytological/structural atypia and confounding benign conditions.

Expression of the oncofetal protein IGF2BP3 in endometrial clear cell carcinoma: assessment of frequency and significance

Insulin-like growth factor-II messenger RNA-binding protein 3 (IGF2BP3 or IMP3) is a biomarker whose expression has been found to be a negative prognostic factor in several neoplasms including ovarian clear cell carcinoma (CCC). In this study, we analyzed the frequency and clinicopathologic significance of IMP3 expression, as assessed by immunohistochemistry and as scored using a modified H-score system, in a cohort of 50 endometrial CCCs. Cases with scores of 0 to 100, 101 to 200, and 201 to 300 were classified as negative/mildly positive (n = 17), moderately positive (n = 20), and strongly positive (n = 13), respectively. A distinctive pattern of increased staining at the myoinvasive front (relative to the main tumor) was evident in 46% of the cases with evaluable foci of myometrial invasion. Moderate/strong IMP3 staining was associated with a tumor architectural pattern that has been reported to be of poor prognostic significance: at least 10% of the tumor composed of solid architecture or individual infiltrating tumor cells (P = .01). Increasing levels of IMP3 expression showed a trend toward decreasing relapse-free survival (RFS; median survival, 75.6, 81.3, and 48.4 months for the negative/mildly, moderately, and strongly positive groups, respectively [P = .09]). However, IMP3 expression was not significantly associated with reduced overall survival or RFS in a multivariate analytic model. The finding in a subset of our cases of increased IMP3 expression at the tumoral myoinvasive front is consistent with a role for IMP3 in invasiveness, as is the trend toward reduced RFS in cases expressing IMP3 at high levels. These preliminary findings suggest that IMP3 expression may be involved in the pathogenesis of CCC and is worthy of further exploration.

Molecular evaluation of Glypican 3 gene expression in Egyptian patients with Hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is one of the most deadly cancers worldwide and it represents a major world health problem. The burden of hepatocellular carcinoma (HCC) has been increasing in Egypt with a doubling in the incidence rate in the past 10 years. . The genetic alterations that take place in the transformation of normal cells to neoplastic cells give an insight into the molecular mechanism of the disease. Glypican 3 (GPC3) is protein that plays a role in the control of cell division and growth regulation. It acts as a tumor suppressor gene in some tissues, while acting as an oncofetal protein in other tissues. The aim of this work was to study gene expression of GPC 3 in HCC patients in Egypt. This was an internally controlled case series where HCC tumor tissue and non-tumor tissue from the same patient were analyzed for the expression of GPC 3. This study showed that statistically no significant positive correlation between AFP and GPC3 was observed. So, GPC 3 may serve as a potential marker for the diagnosis and prognosis HCC. Keywords : HCC, Glypican 3

Oncofetal protein IMP3: a useful diagnostic biomarker for leiomyosarcoma

Oncofetal protein IMP3: a useful diagnostic biomarker for leiomyosarcoma

Expression of insulin-like growth factor II mRNA-binding protein 3 predicts early recurrence and poor prognosis in intrahepatic cholangiocarcinoma

IntroductionInsulin-like growth factor-II mRNA-binding protein 3 (IMP3), a newly identified oncofetal RNA-binding protein, plays a pivotal role in the regulation of cell growth and migration during early stages of embryogenesis, and is found to be expressed in various human cancers. In this study, we elucidated the clinicopathological significance of IMP3 expression in intrahepatic cholangiocarcinoma (ICC). MethodsFrom March 1995 to December 2003, 61 surgically resected, unifocal primary ICCs were studied. IMP3 protein expression was detected by immunohistochemical staining. ResultsIMP3 protein was expressed in 25 of 61 ICCs (41.0%). In addition to correlating with tumor grade (p = 0.0276), tumor stage (p = 0.0059), lymphovascular invasion (p = 0.0198), serum carbohydrate antigen 19-9 level (p = 0.0146), IMP3 expression predicted early tumor recurrence (ETR) (p = 0.0059) and was a strong indicator of worse disease-free survival (p = 0.0001) and overall survival (p = 0.0007). Even though we did not find that IMP3 expression exerted prognostic impact independent of tumor stage, multivariate analysis confirmed that IMP3 expression was an independent risk factor of high-stage tumor and ETR (p = 0.0170, and p = 0.0052, respectively), and thus it contributed to poor prognosis in ICC patients. ConclusionsIMP3 expression can serve as a novel maker for ETR and prognostic prediction, and may be a target for adjuvant therapy of patients with ICC after tumor resection.

Preparation and Characterization of Monoclonal Antibody Against Glypican-3

Glypican-3 (GPC3) has been reported as a novel serum and histochemical marker for hepatocellular carcinoma (HCC) by several groups. As an oncofetal protein, it is expressed abundantly in the fetal liver, inactive in the normal adult liver, and frequently reactivated in HCC. Immunology reagents are urgently needed to proceed with mechanism-related research, clinical validation, and application. In this report, monoclonal antibodies (MAbs) against GPC3 were made from hyperimmune BALB/c mice by injecting 100 μg of purified antigen intraperitoneally. Hybridomas were screened by indirect enzyme-linked immunosorbent assay (ELISA) using purified protein. Finally 13 mouse hybridomas producing MAbs to GPC3 were established. The MAbs obtained were fully characterized using Western blot analysis, immunofluorescence, and immunohistochemistry. The results showed that these antibodies could be used for preliminary application of the next step mechanism-related research and GPC3 expression level analysis.

IMP3 can predict aggressive behaviour of lung adenocarcinoma

BackgroundLung cancer most often presents as an inoperable tumour and the diagnosis is usually performed on a small biopsy/cytology specimen. In the group of non small cell lung cancer - not otherwise specified, adenocarcinoma phenotype can be determined immunohistochemically using TTF-1 and Napsin A. Expression of oncofetal protein IMP3 in human cancer is associated with poor differentiation and aggressive behaviour. In the present study expression of IMP3 was correlated with expression of TTF-1 and Napsin A, histological subtype and clinical stage of lung adenocarcinoma. We were interested whether distant metastases are associated with IMP3 overexpression, regardless of the histologic subtype of adenocarcinoma.MethodsIn retrospective study, consecutive series of 105 patients with advanced lung adenocarcinoma diagnosed from 2006 to 2009 in Clinical Hospital Center Split, Croatia, were analysed. Clinical data were collected from the Pulmology Department and time of death from the Mortality Registry. Paraffin blocks of bronchoscopic biopsies were collected from the Institute of Pathology and 15 cases excluded from the analysis due to insufficient material. Expression of IMP3, Napsin A and TTF-1 were analysed by indirect enzyme immunohistochemistry. Statistical analysis was performed and P values less than 0.05 considered significant.ResultsOf 90 patients, 71 (78%) were males and 19 (22%) females. Median age for males was 61.5 years (min-max 43–83) and for females 61 years (min-max 44–86). Pleural effusion was found in 15 (16.6%) and distant metastases in 45 (50%) cases. According to histological subtypes, there were 34 acinar, 2 lepidic, 2 papillary and 52 solid subtypes. IMP3 overexpression was found in 63 cases (70%) and was correlated with solid subtype (P = 0.002) and negative/weak Napsin A expression (P = 0.004). Strong Napsin A expression correlated with TTF-1 expression (P = 0.003) and lower histological grades (P = 0.031). Patients with IMP3 overexpression more often had distant metastases than patients with negative IMP3, 55.5% versus 33.3% (P = 0.033). Non solid subtypes with IMP3 overexpression developed distant metastasis more common than non solid subtypes with negative IMP3, 72% versus 35% (P = 0.028).ConclusionsExpression of IMP3 correlates with solid subtype and with distant metastases regardless of histological subtype of lung adenocarcinoma.Virtual slideshttp://www.diagnosticpathology.diagnomx.eu/vs/1966211581795258ZusammenfassungHintergrundDas Lungenkarzinom kommt meistens als nicht resektabler Tumor vor und die Diagnose kann nur in kleinen Biopsaten oder zytologisch gestellt werden. In der Gruppe der nicht kleinzelligen Lungenkarzinome kann der nicht anders spezifizierte Adenokarzinom Phänotyp mit Hilfe der Antikörper TTF-1 und Napsin A diagnostiziert werden. Die Expression des onkoföetalen Proteins IMP3 ist bei humanen Karzinomen mit agressivem Verhalten und metastatischem Potential verbunden. In dieser Studie korreliert die Expression von IMP3 mit TTF-1, Napsin A, histologischem Typ und klinischem Staging des Lungenkarzinoms. Wir waren daran interessiert, ob Fernmetastasen mit IMP3 Überexpression assoziiert sind, unabhängig von der histologischen Subtyp von Adenokarzinom.MethodeIn der retrospektiven Studie wurden die von 2006 bis 2009 im Klinischem Krankenhaus Split, Kroatien diagnostizerte Adenokarzinome der Lunge von 105 Patienten analysiert. Die klinischen Daten stammten aus der Abteilung für Pulmologie und im Falle des Todes vom Todesregister. Die Paraffinblöcke der primären Lungenbiopsate dieser Patienten wurden im Institut für Pathologie mit der indirekter Enzym - Immunohistochemie mittels Kombination der Antikörper gegen IMP3, Napsin A und TTF1 untersucht. 15 Fälle aus der Analyse aufgrund unzureichender Material ausgeschlossen. Es wurde eine statistische Untersuchung durchgeführt und Werte weniger als 0.05 P wurden als statistisch signifikant bezeichnet.ErgebnisseVon 90 Patienten mit Lungencarcinom waren 71 (78%) mänlich, durchschnittliches Alter war für Männer 61.5 Jahre (min-max 43–83) und 61 Jahre für Frauen (min-max 44–86). Pleurale Effusionen fand man in 15 Fällen (16.6%) und Fernmetastasen in 45 (50%) Fällen. Histologische Sybtypen waren: 2 lepidic Karzinome, 34 azinäre Karzinome, 2 papilläre und 52 solide Karzinome. IMP3 war exprimiert in 63 Fälle (70%). Positive IMP3 Expression war mit solidem Typ (P = 0.002) und negativer Napsin A Expression (P = 0.004) assoziert. Napsin A Expression war mit niedrigem Gradus (P = 0.031) und positiver TTF-1 Expression (P = 0.003) assoziert. Patienten mit IMP3 Überexpression öfter hatten Fernmetastasen als Patienten mit negativen IMP3, 55.5% versus 33.3% (P = 0.033). Non solide Subtyp mit IMP3 Überexpression entwickelten Fernmetastasen Meer häufiger als nicht festem Subtyp mit negativen IMP3, 72% versus 35% (P = 0.028).SchlussworteDie Expression von IMP3 ist mit negaativer Expression von Napsin A, solidem Subtyp und Metastasen verbunden und hat praktische predictive Werte in der pathologischen Diagnose des Adenokarzinoms der Lunge. Die Expression von IMP3 korreliert mit soliden Subtyp und mit Fernmetastasen unabhängig von histologische Subtyp Lungenadenokarzinom.

KOC (K homology domain containing protein overexpressed in cancer) overexpression and progression-free survival after curative intent resection of pancreatic ductal adenocarcinoma.

48 Background: Pancreatic ductal adenocarcinoma (PDAC) is the fourth leading cause of cancer mortality in the United States. Unfortunately, effective screening and early detection mechanisms are currently unavailable, thereby 80% of patients present with distant metastasis. Of the subset of patients eligible for curative intent surgery, the 5-year survival rate is only 20%. Negative surgical margins, tumor size, stage, and node negative disease are traditional prognostic indicators. However, these can be limited in their ability to predict patient specific prognosis. KOC is an oncofetal RNA-binding protein involved in RNA stabilization and cell growth during embryogenesis. Previous studies have revealed that KOC mRNA is inappropriately overexpressed in pancreatic cancer and that increased expression correlates with tumor stage. In this study, we attempt to identify whether KOC expression in patients who undergo curative intent surgery correlates with progression free survival. Methods: Tissue microarrays prepared from formalin-fixed, paraffin-embedded specimens of patients with PDAC who underwent curative intent surgery were assessed by immunohistochemistry. Results: A total of 35 patients were included. Comparisons between groups on progression free survival are estimated using the Kaplan-Meier method and the log-rank test. KOC was overexpressed in 23.6% of tumors. It was found that there were zero patients with a high KOC expression and no distant metastasis. Patients with a high KOC expression were more than 3 times more likely to progress compared to those with a low KOC expression (HR=3.54, 95% CI: 1.34, 9.36, p=0.011). Conclusions: KOC is a useful prognostic biomarker for predicting those patients with PDAC who have a high risk for early progression and distant metastasis. Identifying patients with high KOC expression upon initial diagnosis can serve as a way to risk stratify patients to aggressive treatment regimens upfront and early exposure to clinical trials.

Insulin-like growth factor 2 mRNA-binding proteins (IGF2BPs): post-transcriptional drivers of cancer progression?

The insulin-like growth factor-2 mRNA-binding proteins 1, 2, and 3 (IGF2BP1, IGF2BP2, IGF2BP3) belong to a conserved family of RNA-binding, oncofetal proteins. Several studies have shown that these proteins act in various important aspects of cell function, such as cell polarization, migration, morphology, metabolism, proliferation and differentiation. In this review, we discuss the IGF2BP family’s role in cancer biology and how this correlates with their proposed functions during embryogenesis. IGF2BPs are mainly expressed in the embryo, in contrast with comparatively lower or negotiable levels in adult tissues. IGF2BP1 and IGF2BP3 have been found to be re-expressed in several aggressive cancer types. Control of IGF2BPs’ expression is not well understood; however, let-7 microRNAs, β-catenin (CTNNB1) and MYC have been proposed to be involved in their regulation. In contrast to many other RNA-binding proteins, IGF2BPs are almost exclusively observed in the cytoplasm where they associate with target mRNAs in cytoplasmic ribonucleoprotein complexes (mRNPs). During development, IGF2BPs are required for proper nerve cell migration and morphological development, presumably involving the control of cytoskeletal remodeling and dynamics, respectively. Likewise, IGF2BPs modulate cell polarization, adhesion and migration in tumor-derived cells. Moreover, they are highly associated with cancer metastasis and the expression of oncogenic factors (KRAS, MYC and MDR1). However, a pro-metastatic role of IGF2BPs remains controversial due to the lack of ‘classical’ in vivo studies. Nonetheless, IGF2BPs could provide valuable targets in cancer treatment with many of their in vivo roles to be fully elucidated.Electronic supplementary materialThe online version of this article (doi:10.1007/s00018-012-1186-z) contains supplementary material, which is available to authorized users.

MDR1-P-glycoprotein behaves as an oncofetal protein that promotes cell survival in gastric cancer cells

P-glycoprotein (P-gp), traditionally linked to cancer poor prognosis and multidrug resistance, is undetectable in normal gastric mucosa and overexpressed in gastric cancer (GC). We propose that P-gp may be involved in Helicobacter pylori (Hp)-related gastric carcinogenesis by inhibiting apoptosis. Aim of the study was to evaluate the expression of P-gp in fetal stomach and in Hp-related gastric carcinogenesis, the epigenetic control of the multi-drug resistance-1 (MDR1) gene, the localization and interaction between P-gp and Bcl-xL and the effect of the selective silencing of P-gp on cell survival. P-gp and Bcl-xl expression was evaluated by immunohistochemistry on 28 spontaneously abortive human fetuses, 66 Hp-negative subjects, 138 Hp-positive chronic gastritis (CG) of whom 28 with intestinal metaplasia (IM) and 45 intestinal type GCs. P-gp/Bcl-xL colocalization was investigated by confocal immunofluorescence microscopy and protein–protein interaction by co-immunoprecipitation, in basal conditions and after stress-induced apoptosis, in GC cell lines AGS and MKN-28 and hepatocellular carcinoma cell line Hep-G2. The role of P-gp in controlling apoptosis was evaluated by knocking down its expression with a specific small interfering RNAs in stressed AGS and MKN-28 cell lines. P-gp is expressed in the gastric mucosa of all human fetuses while, it is undetectable in adult normal mucosa and re-expressed in 30/110 Hp-positive non-IM-CG, 28/28 IM-CG and 40/45 GCs. P-gp expression directly correlates with that of Bcl-xL and with the promoter hypomethylation of the MDR1 gene. In GC cell lines, P-gp is localized on the plasma membrane and mitochondria where it colocalizes with Bcl-xL. Co-immunoprecipitation confirms the physical interaction between P-gp and Bcl-xL in AGS, MKN-28 and Hep-G2, at both basal level and after stress-induced apoptosis. The selective silencing of P-gp sensitizes GC cells to stress-induced apoptosis. P-gp behaves as an oncofetal protein that, by cross-talking with Bcl-xL, acts as an anti-apoptotic agent in Hp-related gastric carcinogenesis.

Poster 58: IMP3: A Putative Protein Signaling Eminent Malignant Transformation

Insulin-like growth factor II mRNA-binding protein 3 (IMP3) is a protein that is involved in highly proliferative growth states ie, embryogenesis and carcinogenesis. By virtue of its binding to a key growth regulatory component, IGF II leader-3 mRNA, IMP3 controls essential growth regulatory aspects including RNA binding, trafficking and stabilization, cellular maturation and migration. Recently, IMP3's potential to function as an oncofetal protein has been recognized along with the potential for IMP3 expression to serve as an indicator of eminent malignant transformation.

Congenital Deficiency versus Hereditary Persistence of Human Alpha-fetoprotein: A Meta-analysis and Overview of Potential Biomedical Consequences

Human alpha-fetoprotein (AFP) is a 70 kD tumor-associated fetal protein (oncofetal protein) which has been utilized clinically as a biomarker for both multiple cancers and for fetal defects including neural tube defects and chromosomal abnormalities. Extreme low and high levels of serum AFP in conjunction with gene mutations have now been established in disorders such as congenital deficiency (CD) and hereditary persistence (HP) of AFP. The objectives of the present review are to compare the clinical manifestations and analyze the mutational basis of these two AFP genetic disorders in accordance with presently accepted models of AFP gene regulation. The regulatory elements of AFP gene expression i.e., enhancers, promoters, and silencers are described in light of the genetic alterations expressed by the CD- and HP-AFP patients. By use of structure/function peptide mapping of the full-length AFP amino acid sequence, the potential biomedical consequences exhibited by CD-AFP and HP-AFP patients are presented and discussed. A new prospective on placental dysfunction in these AFP genetic disorders has also been introduced. Using AFP reference levels in maternal serum, cord blood, newborn blood, pediatric and adult serum, AFP serum concentrations are presented that could alert the obstetrician of potential CD-AFP during pregnancy. Knowledge of such serum values could provide tools to allow clinicians to distinguish between adult HP-AFP and malignant/non-malignant diseases such as liver and germ cell tumors, cirrhosis, hepatitis, and various liver disorders. Knowledge of AFP reference levels might serve to guide the clinician in avoiding: a) misguided diagnoses; b) unnecessary treatments and therapies; and c) undue anxieties and stress during pregnant and non-pregnant states.