Epidermal growth factor receptor signaling pathway is frequently altered in ampullary carcinoma at protein and genetic levels

Our objective was to explore alteration of the epidermal growth factor receptor (EGFR) signaling pathway in ampullary carcinoma. Immunohistochemical studies were employed to evaluate expression of amphiregulin as well as expression and activation of EGFR. A lab-developed assay was used to identify mutations in the EGFR pathway genes, including KRAS, BRAF, PIK3CA, PTEN, and AKT1. A total of 52 ampullary carcinomas were identified, including 25 intestinal-type and 24 pancreatobiliary-type tumors, with the intestinal type being associated with a younger age at diagnosis (P=0.03) and a better prognosis (P<0.01). Expression of amphiregulin correlated with better differentiation (P<0.01), but no difference was observed between two major histologic types. Expression and activation of EGFR was more commonly seen in the pancreatobiliary type (P<0.01). Mutations were detected in 50% of the pancreatobiliary type and 60% of the intestinal type. KRAS was the most common gene mutated in the pancreatobiliary type (42%) as well as the intestinal type (52%). Other mutations detected included PIK3CA, SMAD4 and BRAF. KRAS mutations at codons 12 and 13 did not adversely affect overall survival. In conclusion, EGFR expression and activation were different between intestinal- and pancreatobiliary-type ampullary carcinoma. KRAS mutation was common in both histologic types; however, the incidence appeared to be lower in the pancreatobiliary type compared with its pancreatic counterpart, pancreatic ductal adenocarcinoma. Mutational analysis of the EGFR pathway genes may provide important insights into personalized treatment for patients with ampullary carcinoma.

Oncogenic Ras induces inflammatory cytokine production by upregulating the squamous cell carcinoma antigens SerpinB3/B4

Mounting evidence indicates that oncogenic Ras can modulate cell autonomous inflammatory cytokine production, although the underlying mechanism remains unclear. Here we show that squamous cell carcinoma antigens 1 and 2 (SCCA1/2), members of the Serpin family of serine/cysteine protease inhibitors, are transcriptionally up-regulated by oncogenic Ras via MAPK and the ETS family transcription factor PEA3. Increased SCCA expression leads to inhibition of protein turnover, unfolded protein response, activation of NF-κB, and is essential for Ras-mediated cytokine production and tumor growth. Analysis of human colorectal and pancreatic tumor samples reveals a positive correlation between Ras mutation, enhanced SCCA expression, and IL-6 expression. These results indicate that SCCA is a Ras-responsive factor that has a role in Ras-associated cytokine production and tumorigenesis.

Differentiation of pancreatic ductal adenocarcinoma from chronic pancreatitis by PAM4 immunohistochemistry

CONTEXT

PAM4 is a monoclonal antibody that shows high specificity for pancreatic ductal adenocarcinoma (PDAC) and its neoplastic precursor lesions. A PAM4-based serum immunoassay is able to detect 71% of early-stage patients and 91% with advanced disease. However, approximately 20% of patients diagnosed with chronic pancreatitis (CP) are also positive for circulating PAM4 antigen. The specificity of the PAM4 antibody is critical to the interpretation of the serum-based and immunohistochemical assays for detection of PDAC.

OBJECTIVE

To determine whether PAM4 can differentiate PDAC from nonneoplastic lesions of the pancreas.

DESIGN

Tissue microarrays of PDAC (N = 43) and surgical specimens from CP (N = 32) and benign cystic lesions (N = 19) were evaluated for expression of the PAM4 biomarker, MUC1, MUC4, CEACAM5/6, and CA19-9.

RESULTS

PAM4 and monoclonal antibodies (MAbs) to MUC1, MUC4, CEACAM5/6, and CA19-9 were each reactive with the majority of PDAC cases; however, PAM4 was the only monoclonal antibody not to react with adjacent, nonneoplastic parenchyma. Although PAM4 labeled 19% (6 of 32) of CP specimens, reactivity was restricted to pancreatic intraepithelial neoplasia associated with CP; inflamed tissues were negative in all cases. In contrast, MUC1, MUC4, CEACAM5/6, and CA19-9 were detected in 90%, 78%, 97%, and 100% of CP, respectively, with reactivity also present in nonneoplastic inflamed tissue.

CONCLUSIONS

PAM4 was the only monoclonal antibody able to differentiate PDAC (and pancreatic intraepithelial neoplasia precursor lesions) from benign, nonneoplastic tissues of the pancreas. These results suggest the use of PAM4 for evaluation of tissue specimens, and support its role as an immunoassay for detection of PDAC.

Fibrogenesis in pancreatic cancer is a dynamic process regulated by macrophage-stellate cell interaction

Pancreatic cancer occurs in the setting of a profound fibrotic microenvironment that often dwarfs the actual tumor. Although pancreatic fibrosis has been well studied in chronic pancreatitis, its development in pancreatic cancer is much less well understood. This article describes the dynamic remodeling that occurs from pancreatic precursors (pancreatic intraepithelial neoplasias (PanINs)) to pancreatic ductal adenocarcinoma, highlighting similarities and differences between benign and malignant disease. Although collagen matrix is a commonality throughout this process, early stage PanINs are virtually free of periostin while late stage PanIN and pancreatic cancer are surrounded by an increasing abundance of this extracellular matrix protein. Myofibroblasts also become increasingly abundant during progression from PanIN to cancer. From the earliest stages of fibrogenesis, macrophages are associated with this ongoing process. In vitro co-culture indicates there is cross-regulation between macrophages and pancreatic stellate cells (PaSCs), precursors to at least some of the fibrotic cell populations. When quiescent PaSCs were co-cultured with macrophage cell lines, the stellate cells became activated and the macrophages increased cytokine production. In summary, fibrosis in pancreatic cancer involves a complex interplay of cells and matrices that regulate not only the tumor epithelium but the composition of the microenvironment itself.

Poorly differentiated neuroendocrine carcinomas of the pancreas: a clinicopathologic analysis of 44 cases

BACKGROUND

In the pancreas, poorly differentiated neuroendocrine carcinomas include small cell carcinoma and large cell neuroendocrine carcinoma and are rare; data regarding their pathologic and clinical features are very limited.

DESIGN

A total of 107 pancreatic resections originally diagnosed as poorly differentiated neuroendocrine carcinomas were reassessed using the classification and grading (mitotic rate/Ki67 index) criteria put forth by the World Health Organization in 2010 for the gastroenteropancreatic system. Immunohistochemical labeling for neuroendocrine and acinar differentiation markers was performed. Sixty-three cases were reclassified, mostly as well-differentiated neuroendocrine tumor (NET) or acinar cell carcinoma, and eliminated. The clinicopathologic features and survival of the remaining 44 poorly differentiated neuroendocrine carcinomas were further assessed.

RESULTS

The mean patient age was 59 years (range, 21 to 82 y), and the male/female ratio was 1.4. Twenty-seven tumors were located in the head of the pancreas, 3 in the body, and 11 in the tail. The median tumor size was 4 cm (range, 2 to 18 cm). Twenty-seven tumors were large cell neuroendocrine carcinomas, and 17 were small cell carcinomas (mean mitotic rate, 37/10 and 51/10 HPF; mean Ki67 index, 66% and 75%, respectively). Eight tumors had combined components, mostly adenocarcinomas. In addition, 2 tumors had components of well-differentiated NET. Eighty-eight percent of the patients had nodal or distant metastatic disease at presentation, and an additional 7% developed metastases subsequently. Follow-up information was available for 43 patients; 33 died of disease, with a median survival of 11 months (range, 0 to 104 mo); 8 were alive with disease, with a median follow-up of 19.5 months (range, 0 to 71 mo). The 2- and 5-year survival rates were 22.5% and 16.1%, respectively.

CONCLUSIONS

Poorly differentiated neuroendocrine carcinoma of the pancreas is a highly aggressive neoplasm, with frequent metastases and poor survival. Most patients die within less than a year. Most (61%) are large cell neuroendocrine carcinomas. Well-differentiated NET and acinar cell carcinoma are often misdiagnosed as poorly differentiated neuroendocrine carcinoma, emphasizing that diagnostic criteria need to be clearly followed to ensure accurate diagnosis.

Endomyometriosis ("Uterus-like mass") in an XY Male: Case Report With Molecular Confirmation and Literature Review

Male endometriosis and endomyometriosis (also termed "uterus-like mass") are 2 unusual manifestations of endometriosis. We report a case of male endomyometriosis with immunohistochemical and molecular confirmation. A 52-year-old man presented with stabbing pelvic pain. Computed tomography scan showed a mass in the right inguinal area, at the site of prior hernia repair. The lesion was tubular in shape, with a thick muscular wall and a central blood-filled lumen. Microscopically, the tissue showed layers of concentric smooth muscle, with endometrial glands and stroma lining the lumen. Many theories have been proposed regarding the etiology of both endomyometriosis and male endometriosis, including remnant rests of Müllerian tissue and metaplasia. Cases of male endometriosis typically have been linked to estrogen therapy for prostate cancer. Our patient had a history of cirrhosis and took spironolactone, possibly leading to an altered hormonal state that interacted with a reactive/metaplastic process at a site of prior surgery.

Synthesis and characterization of two-dimensional Nb4C3 (MXene)

By etching Nb₄AlC₃ powders in hydrofluoric acid, a phase-pure, highly conductive, Nb₄C₃ MXene – the second with formula M₄X₃ – was produced. The latter's structure was investigated using pair distribution function analysis.

Endoscopic mucosal resection of Barrett’s esophagus detects high prevalence of subsquamous intestinal metaplasia

AIM: To report the prevalence of Subsquamous intestinal metaplasia (SSIM) in patients undergoing endoscopic mucosal resection (EMR) for staging of Barrett’s esophagus (BE).

METHODS: Thirty-three patients with BE associated neoplasia underwent EMR at our institution between September 2009 and September 2011; 22 of these patients met study inclusion criteria. EMR was targeted at focal abnormalities within the BE segment. EMR was performed in standardized fashion using a cap-assisted band ligation technique, and resection specimens were assessed for the presence of SSIM. Demographic and clinical data were analyzed to determine predictors of SSIM.

RESULTS: SSIM was detected in 59% of patients. SSIM was detected in 73% of patients with short segment (< 3 cm) BE, and in 45% of patients with long-segment (≥ 3 cm) BE (P = NS). There was no association between presence/absence of SSIM and age, gender, or stage of BE-associated neoplasia.

CONCLUSION: EMR detects SSIM in a majority of patients with BE-associated neoplasia. While the long-term clinical significance of SSIM remains uncertain, these results highlight the importance of EMR as an optimal diagnostic tool for staging of BE and detection of SSIM, and should further limit concerns that SSIM is purely a post-ablation phenomenon.

Direct targeting of SUZ12/ROCK2 by miR-200b/c inhibits cholangiocarcinoma tumourigenesis and metastasis

Background:

The multidrug resistance and distant metastasis of cholangiocarcinoma result in high postoperative recurrence and low long-term survival rates. It has been demonstrated that the ectopic expression of miR-200 suppresses the multidrug resistance and metastasis of cancer. However, the expression and function of miR-200 in cholangiocarcinoma has not yet been described.

Methods:

In this study, we identified dysregulated microRNAs (miRNAs, miR) in cholangiocarcinoma tissue by microarray analysis, and subsequent real-time PCR and northern blot analyses validated the expression of candidate miR. We performed functional analyses and investigated the relationship between miR-200b/c expression and the properties of cholangiocarcinoma cells. A dual luciferase assay was applied to examine the effect of miRNAs on the 3′-UTR of target genes, and we demonstrated the function of the target gene by siRNA transfection identifying the downstream pathway via western blotting.

Results:

We found significantly downregulated expression of four miR-200 family members (miR-200a/b/c/429) and then confirmed that ectopic miR-200b/200c inhibits the migration and invasion of cholangiocarcinoma cells both in vitro and in vivo. We found that miR-200b/c influenced the tumourigenesis of cholangiocarcinoma cells including their tumour-initiating capacity, sphere formation, and drug resistance. We further found that miR-200b/c regulated migration and invasion capacities by directly targeting rho-kinase 2 and regulated tumorigenic properties by directly targeting SUZ12 (a subunit of a polycomb repressor complex).

Conclusion:

Our study shows that miR-200b/c has a critical role in the regulation of the tumorigenic and metastatic capacity of cholangiocarcinoma and reveals the probable underlying mechanisms.

Diagnostic and therapeutic implications of a novel immunohistochemical panel detecting duodenal mucosal invasion by pancreatic ductal adenocarcinoma

BACKGROUND

We investigated a series of pancreaticoduodenectomy and duodenal biopsies with a panel of immunohistochemical markers to identify duodenal mucosal invasion by pancreatic ductal adenocarcinoma (PDAC), including markers of poor prognosis and targets of promising novel immunotherapies.

MATERIALS AND METHODS

Eighteen consecutive pancreaticoduodenectomy specimens with duodenal mucosal invasion by PDAC were examined for expression of MUC1, MUC4, MUC5AC, MUC6, mesothelin, MUC2, CDX2, and DPC4 on formalin-fixed, paraffin-embedded sections of duodenal-ampullary-pancreatic junctions. Expression of all but MUC6 was also assessed in duodenal biopsies from 12 patients with duodenal mucosal invasion by PDAC.

RESULTS

The duodenal mucosa expressed MUC1 (crypts), MUC2 (goblet cells), MUC6 (Brunner glands), CDX2, and DPC4. PDACs in the duodenal mucosa from the resection (n=16-18) and biopsy (n=12) specimens were marked as follows: MUC1 100% (30/30), MUC4 83% (24/29), MUC5AC 83% (25/30), mesothelin 82% (23/28), MUC2 7% (2/30), and CDX2 36% (10/28). Loss of DPC4 expression was seen in 16 of 29 (55%) cases. Reactive mucosa adjacent to PDAC expressed MUC4, MUC5AC and mesothelin in 65% (17/26), 19% (5/27), and 19% (5/26) of cases, respectively. While MUC5AC and mesothelin had high diagnostic accuracy for detection of PDAC, MUC2, CDX2 and DPC4 expression demonstrated negative correlation with PDAC, with absent expression being highly specific for PDAC.

CONCLUSION

Immunohistochemical labeling for PDAC biomarkers may aid the diagnosis of PDAC in duodenal biopsy, especially in situations where diagnosis of a pancreatic mass is challenging.

A gEUD-based inverse planning technique for HDR prostate brachytherapy: feasibility study

PURPOSE

The purpose of this work was to study the feasibility of a new inverse planning technique based on the generalized equivalent uniform dose for image-guided high dose rate (HDR) prostate cancer brachytherapy in comparison to conventional dose-volume based optimization.

METHODS

The quality of 12 clinical HDR brachytherapy implants for prostate utilizing HIPO (Hybrid Inverse Planning Optimization) is compared with alternative plans, which were produced through inverse planning using the generalized equivalent uniform dose (gEUD). All the common dose-volume indices for the prostate and the organs at risk were considered together with radiobiological measures. The clinical effectiveness of the different dose distributions was investigated by comparing dose volume histogram and gEUD evaluators.

RESULTS

Our results demonstrate the feasibility of gEUD-based inverse planning in HDR brachytherapy implants for prostate. A statistically significant decrease in D10 or/and final gEUD values for the organs at risk (urethra, bladder, and rectum) was found while improving dose homogeneity or dose conformity of the target volume.

CONCLUSIONS

Following the promising results of gEUD-based optimization in intensity modulated radiation therapy treatment optimization, as reported in the literature, the implementation of a similar model in HDR brachytherapy treatment plan optimization is suggested by this study. The potential of improved sparing of organs at risk was shown for various gEUD-based optimization parameter protocols, which indicates the ability of this method to adapt to the user's preferences.

CpG7909 adjuvant enhanced immunogenicity efficacy in mice immunized with ESAT6-Ag85A fusion protein, but does not confer significant protection against Mycobacterium tuberculosis infection

AIMS

This study aimed to investigate the ability of CpG7909 adjuvant to enhance immunogenicity and protective efficacy of a subunit vaccine composed of ESAT6-Ag85A fusion protein (Pe685a) of Mycobacterium tuberculosis.

METHODS AND RESULTS

ELISA was used to detect specific antibody and IFN-γ expression in sera; ELISPOT, to detect IFN-γ expression in splenocytes; MTT assay and FACS, to detect T-lymphocytes proliferation in spleens; and RT-PCR, to detect cytokines expression in lungs of mice after immunization. Bacterial load and histopathological lesions in lungs or spleens of mice challenged with Myco. tuberculosis H37Rv strain were analysed. Compared with incomplete Freund's adjuvant, CpG7909 induced more potent production of Pe685a-specific IgG2a/IgG1 antibody and higher expression of IFN-γ in sera, stimulated more generation of antigen-specific IFN-γ-secreting splenocytes, enhanced frequencies of CD3(+) CD4(+) and CD3(+) CD8(+) T-lymphocytes in spleen and increased transcription of TNF-α, IFN-γ, IL-6 and TLR9 in lung. However, lower bacterial load in lung and less severe lung pathology were not observed in CpG7909 group mice.

CONCLUSIONS

CpG7909 is able to enhance immunological effects of Pe685a subunit vaccine, but does not confer significant protective efficacy against Myco. tuberculosis infection.

SIGNIFICANCE AND IMPACT OF THE STUDY

CpG7909 as an adjuvant of subunit vaccine against Myco. tuberculosis is worthy of further investigation.

Comparison of prediction equations to estimate glomerular filtration rate in Chinese patients with chronic kidney disease

AIM

We sought to evaluate the applicability of formulae based on serum creatinine (SC) levels in Chinese patients with chronic kidney disease (CKD).

MATERIALS AND METHODS

Three hundred and twenty-seven patients with CKD who had undergone (99m) Tc-DTPA glomerular filtration rate (GFR) estimation were enrolled. The Cockcroft-Gault equation, SC-reciprocal equation, Gate equation, Hull equation, Jelliffe-1973 equation, Jelliffe-1971 equation, Mawer equation, Bjornsson equation, reexpressed 6-variable MDRD equation and reexpressed 4-variable MDRD equation were compared. Using the (99m) Tc-DTPA GFR as the standard GFR (sGFR), the accuracy of estimated GFR was compared with sGFR in various stages of CKD.

RESULTS

Median per cents of the absolute difference ranged from 28.16% to 39.39%, accuracy with a deviation less than 30% ranging from 39.4% to 53.5%, accuracy with a deviation less than 50% ranging from 63.0% to 80.7%. None of the equations had accuracy up to the 70% level with a deviation less than 30% from sGFR. Bland-Altman analysis demonstrated that mean difference ranged from -2.42 to 16.39 mL/min/1.73 m(2), whereas precision ranged from 82.66 to 106.15 mL/min/1.73 m(2). However, the agreement limits of all the equations exceeded the prior acceptable tolerances defined as 60 mL/min/1.73 m(2). Linear regression showed that the slopes of regression line ranged from 0.37 to 0.54 and intercepts ranged from -12.10 to 3.86. When the overall performance as well as bias and accuracy were compared in different stages of CKD, GFR estimated by Jelliffe-1973 equation, Cockcroft-Gault equation and Bjornsson equation showed promising results.

CONCLUSION

When SC was measured by the enzymatic method, GFR estimation equations showed great bias in Chinese CKD patients. At present, the Jelliffe-1973 equation and Cockcroft-Gault equation may be more accurate in the Chinese ethnic group.

Colorectal cancer gene expression profiling using nanostring nCounter analysis

3555

Background: A more accurate method of identifying stage 2 and 3 colorectal cancer (CRC) patients at highest risk for recurrence after surgical resection is needed. Gene expression signatures utilizing microarray-derived gene expression data from fresh frozen primary CRCs to predict risk of recurrence have been developed by us and others. Advances in technology platforms for gene expression measurements and their applicability to formalin-fixed, paraffin-embedded (FFPE) specimens offer new opportunity to develop clinically useful diagnostics based on molecular profiles. Methods: 58 patient FFPE samples of all stages stored from 1-12 years were collected from the Vanderbilt GI SPORE Translational Pathology and Imaging Core and annotated with appropriate clinicopathologic data. 414 genes were selected from our 34-gene prognostic classifier and other published CRC gene signatures, as well as gene elements associated with intestinal stem cell biology and epithelial-to-mesenchymal transition (EMT). RNA was extracted from the tumors, and gene expression analysis was completed using the nCounterplatform. Results: Quality of extracted RNA from tumor blocks was similar among the tumors and adequate for analysis. No significant differences were seen in signal strength (p=0.94, Kruskal-Wallis test) or intra-class variation (correlation coefficient = 0.99) across material extracted from new and old blocks. Fold change values for the 70 most highly differentially expressed genes on the nCounter platform correlated well with Affymetrix U133 plus 2 microarray (R2=0.819). Genes associated with EMT clustered according to prognosis, with poorer prognoses seen in patients with high TWIST expression or low E-cadherin and SMAD4 expression. There was a trend toward better survival outcomes with high expression of E-cadherin and SMAD4 (p=0.072, log-rank test). Conclusions: This preliminary study demonstrates the feasibility of this approach to determine gene expression patterns in FFPE tumor tissue samples. Our data suggest that this approach may be applied to identify clinically applicable prognostic gene expression profiles that may be validated in archived patient samples that are well annotated with patient outcome data.

Temporal alterations and cellular mechanisms of transmural repolarization during progression of mouse cardiac hypertrophy and failure

AIM

The remodelling of transmural dispersion of repolarization (TDR) in human heart failure (HF) and in different animal models of cardiac hypertrophy or HF remains a controversial topic. We hypothesize that TDR may exhibit temporal alterations, depending on the stage of the disease.

METHODS

We systematically investigated the temporal alterations of TDR during the development of cardiac hypertrophy and HF in the mouse pressure-overload model using electrophysiological and molecular biology techniques.

RESULTS

A progressive prolongation of QT interval and changes in the amplitude of the J wave at 2, 5, 9 and 13 weeks were found in anesthetized aorta-banded mice. Action potential duration (APD) at 90% repolarization (APD90) in subendocardial myocytes of the left ventricular free wall remained unchanged at the hypertrophic stage (2 and 5 weeks), but was significantly prolonged in HF mice at 9 and 13 weeks. However, APD90 in subepicardial myocytes exhibited a significant prolongation at 2 weeks and did not progressively extend from 2 weeks to 13 weeks in banded mice. Thus, non-parallel prolongation of APD in subendocardial and subepicardial myocytes led to a reduction in TDR at hypertrophic stage and an amplification of TDR at HF stage. Further experiments revealed that asynchronous down-regulation of voltage-dependent potassium currents (I(to,f), I(K,slow) and I(ss)) and L-type calcium currents (I(Ca-L)) in subendocardial and subepicardial myocytes may contribute to the dynamic remodelling of transmural APD.

CONCLUSION

The two distinct TDR modes were revealed during the progression of mouse cardiac hypertrophy and failure, indicating that the remodelling of TDR depends on the stage of the disease.

Abstract 1141: MAb-PAM4 can differentiate between pancreatic ductal adenocarcinoma and chronic pancreatitis

Background: Due to the asymptomatic nature of pancreatic ductal adenocarcinoma (PDAC) in its early stages of growth, and its relatively low incidence, screening methods have not received high attention. However, with recent studies providing the ability to identify specific patient groups at high risk for PDAC, a rationale exists for longitudinal surveillance as a means to improve early detection specifically in these high-risk settings. Individuals with a family history of PDAC, those patients with long-standing chronic pancreatitis (CP), patients with new-onset diabetes who meet certain other conditions, or those with FAMMM syndrome, etc., could be evaluated on a long-term basis for the detection of early malignant changes by use of a MAb-PAM4-based immunoassay procedure.

Methods: We have developed and validated (in over 600 patient specimens) an enzyme immunoassay (EIA) based upon use of MAb-PAM4 for quantitation of antigen in the serum of patients diagnosed with pancreatic ductal adenocarcinoma. In addition, the antibody has been used for immunohistochemical evaluation of malignant, benign, and normal pancreatic tissues.

Results: 71% of patients with confirmed early-stage disease and 91% with advanced disease were positive by EIA for circulating PAM4-antigen. Overall specificity was 81% with respect to benign pancreatic disease. Of 126 patients diagnosed with benign conditions of the pancreas, 24 (19%) were positive for the PAM4-antigen, with the majority of these cases being diagnosed with chronic pancreatitis [18 of 80 positive (23%)], all of whom had surgical resection performed for severity and/or duration of disease activity. ROC curve analyses of PAM4 assays revealed a statistically significant difference between the PDAC and CP groups (P&lt;0.0001), with an area under the curve of 0.84 ± 0.02 (95% CI: 0.79-0.89). The positive likelihood ratio for differentiating PDAC from benign conditions of the pancreas was 4.00, which was significant (P&lt;0.001). It is very important to emphasize that the “true” specificity of this assay is likely underestimated. Immunohistochemistry data have shown the PAM4-biomarker is absent from normal pancreas and benign, non-neoplastic lesions of the pancreas. In over 50 surgical specimens of CP, the PAM4-biomarker was identified only within PanIN lesions that are associated with long-term CP, and not by the inflamed tissue.

Conclusions: Our results suggest that PAM4-positive CP patients (and likely other PAM4-positive patients diagnosed with benign conditions of the pancreas) may very likely have pancreatic neoplasia (invasive and/or precursor lesions), and therefore should be followed closely. Indeed, such studies might reveal new cutoff values or kinetic changes that would support early surgical intervention. (Supported in part by NIH grant CA096924.)

Citation Format: David V. Gold, Chanjuan Shi, Guy Newsome, David M. Goldenberg. MAb-PAM4 can differentiate between pancreatic ductal adenocarcinoma and chronic pancreatitis. [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 1141. doi:10.1158/1538-7445.AM2013-1141

Management of combined hepatocellular-cholangiocarcinoma: a case report and literature review

Combined hepatocellular-cholangiocarcinoma (cHCC-CC) is a rare type of primary liver cancer comprising histopathological features of both hepatocellular carcinoma (HCC) and cholangiocarcinoma (CC). Because of its rarity and controversial diagnostic criteria, it continues to be poorly understood with a lack of well-delineated treatment options for recurrent or metastatic disease. We report a case of cHCC-CC in a 31-year-old woman with no risk factors for HCC or CC with recurrent pulmonary metastasis treated with systemic chemotherapy.

Human epididymis protein 4 is up-regulated in gastric and pancreatic adenocarcinomas

Upper gastrointestinal neoplasia in the esophagus, stomach, and pancreas is associated with the formation of preneoplastic metaplasias. We have previously reported the up-regulation of human epididymis protein 4 (HE4) in all metaplasias in the stomach of humans and mice. We have now sought to evaluate the expression of HE4 in metaplasias/preneoplastic precursors and cancers of the human stomach, pancreas, and esophagus. Tissue microarrays for gastric cancers, pancreatic cancers, and esophageal adenocarcinoma were stained with antibodies against HE4. Immunostaining was quantified by digital imaging, and the results were evaluated to assess the expression in metaplasias, the expression in cancer pathological subtypes, and the effects of expression on survival in patients with cancer. In patients with gastric cancer from Korea, HE4 was detected in 74% of intestinal and 90% of diffuse cancers, whereas in a gastric cancer cohort from Johns Hopkins, HE4 was detected in 74% of intestinal-type and 92% of diffuse cancers. Nevertheless, in both cohorts, there was no impact of HE4 expression on overall survival. In the esophagus, we observed the expression of HE4 in scattered endocrine cells within Barrett esophagus samples, but Barrett columnar metaplasias and HE4 were detected in only 2% of esophageal adenocarcinomas. Finally, in the pancreas, HE4 expression was not observed in pancreatic intraepithelial neoplasia lesions, but 46.8% of pancreatic adenocarcinomas expressed HE4. Still, we did not observe any influence of HE4 expression on survival. The results suggest that HE4 is up-regulated during gastric and pancreatic carcinogenesis.

Human positive coactivator 4 is a potential novel therapeutic target in non-small cell lung cancer

Transcriptional positive coactivator 4 (PC4) is a multifunctional nuclear protein that has important roles in DNA transcription, replication, repair and heterochromatinization. However, the role of PC4 in cancer remains to be clarified. Several studies propose that PC4 may act as a putative tumor suppressor. Here, we demonstrate for the first time that PC4 may represent a potential therapeutic target in non-small cell lung cancer (NSCLC). PC4 protein expression is significantly upregulated in NSCLC carcinoma tissues compared with their adjacent noncancerous counterparts as shown by immunohistochemical staining and western blotting in 104 pairs of formalin-fixed human NSCLC specimens and 6 fresh NSCLC samples. Knockdown of PC4 expression by sequence-specific small interfering RNA (siRNA) in human NSCLC cells (A549, H460 and H358) significantly inhibits the growth of cancer cells by the induction of cell cycle arrest and the increase of cell apoptosis in vitro. Interrupting the PC4 signaling pathway by injection of the PC4 siRNA liposome complex produced an effective regression of pre-established A549 cell xenografts in mice through growth inhibition and increased apoptosis. These results indicated that PC4 could be an attractive new therapeutic target for the treatment of NSCLC.