Podocalyxin-like protein 1 expression is useful to differentiate pancreatic ductal adenocarcinomas from adenocarcinomas of the biliary and gastrointestinal tracts

Metastases of adenocarcinomas from the pancreas, liver, and gastrointestinal tract are difficult to distinguish from each other because of their similar morphological and immunohistochemical features. So far, no specific marker for pancreatic ductal adenocarcinomas has been described. Podocalyxin-like protein 1 (PODXL-1) is expressed on vascular endothelium, hematopoietic precursor cells, and renal podocytes. We found that 44% (71/160) of pancreatic ductal adenocarcinomas expressed PODXL-1 in a membranous pattern. There was no expression in intrahepatic cholangiocarcinomas (0/18, P < .001), rarely in adenocarcinomas of the extrahepatic bile ducts (1/13, P = .009), and none in duodenal adenocarcinomas (0/5, P = .070). PODXL-1 expression was seen in only 9% of hepatocellular carcinomas (5/56, P < .001), 9% (4/47, P < .001) of gastric carcinomas, 10% of esophageal adenocarcinomas (2/20, P = .003), and 6% of colonic adenocarcinomas (1/17, P = .001). When used as a differential diagnostic marker, ampullary carcinoma needs to be excluded, as 30% (6/20, P = .24) of ampullary carcinomas stain positive, especially those of the signet-ring type (3/3). Adenocarcinomas of the lung and prostate, and liver metastases of colorectal carcinomas lacked PODXL-1 expression. It is concluded that immunoreactivity for PODXL-1 favors a pancreatic origin if ampullary carcinoma is excluded.     

High expression of GRK3 is associated with favorable prognosis in pancreatic ductal adenocarcinoma

Background

It was found that G-protein-coupled receptor kinase 3 (GRK3) played key biological roles in some cancers. However, its associations with clinicopathologic features and prognosis in pancreatic ductal adenocarcinoma (PDAC) remain unknown.

Gene expression profiles of microdissected pancreatic ductal adenocarcinoma

In a search for new molecular markers of pancreatic ductal adenocarcinoma (PDAC), we compared the gene expression profiles of seven pancreatic carcinomas and one carcinoma of the papilla Vateri with those of duct cells from three non-neoplastic pancreatic tissues. In addition, the human pancreatic duct cell line and five PDAC cell lines (AsPC-1, BxPC-3, Capan-1, Capan-2, HPAF) were examined. RNA was extracted from microdissected tissue or cultured cell lines and analysed using a custom-made Affymetrix Chip containing 3023 genes, of which 1000 were known to be tumour associated. Hierarchical clustering revealed 81 differentially expressed genes. Of all the genes, 26 were downregulated in PDAC and 14 were upregulated in PDAC. In PDAC cell lines versus normal pancreatic duct cells, 21 genes were downregulated and 20 were upregulated. Of these 81 differentially expressed genes, 15 represented human genes previously implicated in the tumourigenesis of PDAC. From the genes that were so far not known to be associated with PDAC tumorigenesis, we selected ADAM9 for further validation because of its distinct overexpression in tumour tissue. Using immunohistochemistry, the over-expressed gene, ADAM9, was present in 70% of the PDACs analysed. In conclusion, using microarray technology we were able to identify a set of genes whose aberrant expression was associated with PDAC and may be used to target the disease.     

Expression of urocortin in pancreatic ductal adenocarcinoma and pancreatic intraepithelial neoplasia

Urocortin (UCN) is a 40‐aminoacid neuropeptide that regulates angiogenesis and inhibits cell proliferation. Our aim was to examine the relationship of UCN expression to the clinicopathological parameters of pancreatic ductal adenocarcinoma (PDAC) and histological grade of pancreatic intraepithelial neoplasia (PanIN). Tissue microarray was used to analyze UCN protein expression in 89 surgical specimens including 21 PanIN, 3 PDAC arising from PanIN, and 65 PDAC without PanIN. UCN immunoscores ranging from 0 to 12 were obtained by multiplying intensity (scored on a 3‐point scale) by the percentage of stained cells (scored on a 4‐point scale). Strong expression of UCN was detected in 5 specimens of non‐neoplastic pancreatic ductal epithelia. UCN immunoscore was significantly higher in PanIN‐1 than in PanIN‐2 and PanIN‐3 (p = 0.038) and significantly higher in well‐differentiated PDAC or early American Joint Committee on Cancer (AJCC) stage PDAC than in poorly differentiated or advanced stage PDAC (p = 0.025, p = 0.018). Higher expression of UCN correlates with PDAC tumor grade and AJCC pathologic stage as well as PanIN grade. Immunohistochemical assessment of UCN may help clinicians predict tumor recurrence rate and help pathologists make a proper diagnosis.     

PNMA1 promotes cell growth in human pancreatic ductal adenocarcinoma

Paraneoplastic Ma1 (PNMA1) is a member of an expanding family of ‘brain/testis’ proteins involved in an autoimmune disorder defined as paraneoplastic neurological syndrome (PNS). Although it is widely studied in PNS, little is known about the underlying clinical significance and biological function of PNMA1 in tumors. Here, we find that elevated PNMA1 expression is more commonly observed in pancreatic ductal adenocarcinoma (PDAC) cell lines, compared with normal pancreatic cell and tissues from pancreatic ductal adenocarcinoma patient. Besides, higher PNMA1 expression is closely correlated with large tumor size. Suppression of endogenous PNMA1 expression decreases cell viability and promotes cell apoptosis. Subsequent studies reveal that the PI3K/AKT, MAPK/ERK pathway and members of the anti-apoptotic Bcl-2 family may be involved in the pro-survival and anti-apoptotic effect of PNMA1 on PDAC. Taken together, this study provides evidence that PNMA1 is involved in tumor growth of pancreatic carcinoma and PNMA1-related pathways might represent a new treatment strategy.     

Expression and functional perspectives of miR-184 in pancreatic ductal adenocarcinoma

Pancreatic ductal adenocarcinoma (PDAC) is one of the most aggressive malignant tumors, with its 5-year survival rate lower than 5%. MicroRNAs (miR) have been known as important regulators for the tumorigenesis, progression, invasion and metastasis of various cancers. MiR-184 was found to be abnormally expressed in various cancers including glioma and oral carcinoma. The expression and functional role of miR-184 in PDAC, however, remains unclear. PDAC cell line PANC-1 was transfected with miR-184 inhibitor. Real-time PCR was used to detect the expression of miR-184 in untreated PANC-1, miR-184 inhibitor transfected PANC-1 and controlled normal pancreatic ductal epithelial cell line HPDE6c7. MTT assay was used to detect the effect of miR-184 on the proliferation of PANC-1 cells, while invasion assay and Western blotting were employed to describe the effect on cell invasion ability and expression of caspase-3, respectively. In PANC-1 cells, miR-184 was abundantly expressed. The transfection of inhibitor effectively suppressed the expression of miR-184, and further inhibited both cell proliferation and invasion abilities, in addition to the up-regulation of pro-apoptotic protein caspase 3 expression. The up-regulation of miR-184 in PDAC may facilitate the proliferation and invasion ability, and inhibit apoptosis of tumor cells, thus potentiating the occurrence and development of PDAC. MiR-184, therefore, is a potential molecular target for therapy.     

长链非编码RNA CCHE1在胰腺导管腺癌中的表达及临床意义

目的 检测长链非编码RNA(lncRNA)CCHE1在胰腺导管腺癌(PDAC)细胞和组织中的表达,探讨lncRNA CCHE1与PDAC临床病理特征及预后间的关系.方法 RT-PCR检测PDAC组织及配对癌旁组织以及PDAC细胞和胰腺导管上皮细胞中lncRNA CCHE1的表达;利用单因素方差分析探讨lncRNA CC...     

Cyclin D1 expression in ductal carcinoma in situ, atypical ductal hyperplasia and usual ductal hyperplasia: an immunohistochemical study

The cell cycle regulatory gene, Cyclin D1, plays a critical role in the growth and progression of several types of human cancer, including breast cancer. Immunohistochemical study of Cyclin D1 expression has been extensively reported in invasive ductal carcinoma (IDC). In contrast, there have been few reports concerning Cyclin D1 expression in ductal carcinoma in situ (DCIS) and their positive rates are variable. The differences in the reported frequency may be largely due to the differences in antibodies used, immunohistochemical methods and the positive cut-off point. However, we speculated that the strictness of diagnosis of DCIS might be somewhat responsible for these differences in frequency. Therefore, we selected cases of DCIS by carefully eliminating cases of predominantly intraductal carcinoma (PIC). Moreover, to clarify whether Cyclin D1 expression is involved in multistep carcinogenesis or the progression of human breast cancer, we immunohistochemically investigated Cyclin D1 expression in 57 DCIS, 10 atypical ductal hyperplasia (ADH), 70 usual ductal hyperplasia (UDH), 44 PIC and 92 IDC. Cyclin D1 expression was detected in 41 DCIS cases (72%), 22 PIC cases (50%) and 40 IDC cases (43%). No expression of Cyclin D1 was observed in either ADH or UDH. There were no significant correlations between Cyclin D1 expression and histological grade or estrogen receptor expression in DCIS. These results suggest that Cyclin D1 expression may play an important role in the early stages of carcinogenesis, and that immunohistochemical detection of Cyclin D1 expression may be helpful in differentiating low-grade DCIS from ADH.     

EGFR expression in pancreatic intraepithelial neoplasia and ductal adenocarcinoma

Pancreatic ductal adenocarcinoma (PDA) is an aggressive malignant tumor with poor prognosis. Epidermal growth factor receptor (EGFR) is an important cell adhesion and signaling pathway mediator. The aim of this study was to evaluate the expression of EGFR in both pancreatic intraepithelial neoplasia (PanIN) and PDA and their relationship to clinicopathologic characteristics. Formalin-fixed, paraffin-embedded tissues including 81 cases with pancreatic ductal adenocarcinoma, 27 with normal pancreas, 16 with PanIN-1A, 18 with PanIN-1B, 11 with PanIN-2, and 24 with PanIN-3 were used for construction of tissue microarrays. Imunohistochemistry for EGFR was performed. Normal pancreatic ducts, PanIN-1A, and PanIN-1B did not show EGFR overexpression. EGFR overexpression was observed in 18.2% (2/9) of PanIN-2, 41.7% (10/14) of PanIN-3, and 64.2% (52/81) of PDA, respectively. Significantly higher EGFR overexpression was observed in PDAs than in PanIN lesions (P<0.05). No statistically significant correlation was observed between EGFR overexpression and patient age, sex, tumor location, size, histological grade, vascular invasion, lymph node metastasis and stage at presentation, respectively. In conclusion, EGFR expression increased from PanIN to PDA. EGFR may be involved in early stage in development of PDA.     

Frequency of mismatch repair deficiency in pancreatic ductal adenocarcinoma

Pancreatic ductal adenocarcinoma (PDAC) has an ominous prognosis and there are only few treatment options. It is therefore crucial to investigate possible predictive markers that may improve the treatment of this disease. Mismatch repair (MMR) deficiency (d-MMR), meaning MMR protein loss (l-MMR) and/or microsatellite instability (MSI), is predictive of response to immunotherapy, but its frequency has to our knowledge not been elucidated in Scandinavian PDACs. Our aims were to examine the frequency of d-MMR in a Danish cohort of PDACs. We constructed multi-punch tissue microarrays (TMAs) using primary tumor tissue. Immunohistochemistry (IHC) for the DNA MMR proteins MLH1, MSH2, MSH6 and PMS2 was performed, and their expression was evaluated using a scoring system from 0 to 4. If the overall score was between 0–2 or if IHC was inconclusive for technical reasons, IHC on whole-tissue sections and MSI using PCR was performed. A final score of 0, 1–2 or 3–4 defined the tumor as l-MMR, MMR reduced (r-MMR) or MMR proficient. In total, 4/164 (2.4 %), 2/164 (1.2 %) and 3/164 (1.8 %) were l-MMR, r-MMR, or inconclusive based on IHC. MSI testing of these specimens showed that two of the four l-MMR tumors were MSI-high, while the remaining cases were microsatellite stable (MSS). In conclusion, in this study of Danish PDACss, d-MMR was found in a small proportion of the tumors. For these patients, individualized treatment using immunotherapy could be considered.     

Prognostic significance of immunohistochemical RhoA expression on survival in pancreatic ductal adenocarcinoma: a high-throughput analysis

Among all human carcinomas, pancreatic cancer has one of the worst survival rates. Most patients will die of this cancer shortly after diagnosis, and currently, surgery is the only potential cure. Ductal adenocarcinoma is the most common histologic type. The search for prognostic parameters has progressed from mere physical or histomorphological tumor properties to molecular parameters. These, in turn, might point toward new therapeutic strategies. The K-ras oncogene is known to play a role in early stages of ductal adenocarcinoma carcinogenesis, and ras homologues are differentially expressed in cancerous versus normal ductal cells. RhoA belongs to a family of ras homologues comprising RhoA, RhoB, and RhoC. It is a guanosine triphosphatase associated with the cytoskeleton that seems to be involved in epithelial mesenchymal transition, a process of dedifferentiation. Immunohistologic RhoA expression was studied in a tissue microarray of 94 pancreatic ductal adenocarcinomas and correlated with clinicopathologic parameters and follow-up. RhoA protein expression, measured as labeling intensity or evaluated as percentage of reactive tumor cells, correlated with overall survival. A multivariate analysis demonstrated that RhoA protein expression is independent from other known prognostic parameters such as tumor size or grade. Moreover, a score combining RhoA expression with tumor size and grade resulted in a highly significant increase in the prognostic value for the overall survival of patients with pancreatic ductal adenocarcinoma.     

Correlation of clinicopathological features and leucine-rich repeat-containing G-protein-coupled receptor 5 expression in pancreatic ductal adenocarcinoma

Pancreatic ductal adenocarcinoma (PDAC) is the most common form of pancreatic cancer. Previous studies have established leucine-rich repeat-containing G-protein-coupled receptor 5 (LGR5) as a cancer stem cell marker in gastrointestinal cancers. However, few reports have examined LGR5 in PDAC. Here we examined LGR5 expression and its clinicopathological significance in PDAC. We evaluated LGR5 expression in 78 PDAC patients who underwent surgical resection in our institution using RNAscope, a newly described RNA in situ hybridization technique. All 78 PDAC cases expressed LGR5 in cancer tissues, and LGR5 expression was prominent in the gland-forming part. LGR5 expression was significantly higher in patients with low histological grade (G1–G2) (p < 0.001) and early clinical stage (p = 0.004). Univariate analysis showed that low LGR5 expression (p = 0.034) was significantly associated with worse overall survival. However, LGR5 expression did not remain a predictor of prognosis in multivariate analysis (p = 0.639). All PDAC cases showed LGR5 expression to varying degrees, indicating LGR5 might be a cancer stem cell marker of PDAC, as in gastrointestinal cancer. Reduced LGR5 expression in tumor cells was associated with worse prognosis in PDAC. Further studies are required to elucidate the relationship between tumor progression and LGR5 expression in PDAC.     

PD-L1 expression in pancreatic adenosquamous carcinoma: PD-L1 expression is limited to the squamous component

Aim

We examined the programmed death-ligand 1 (PD-L1) expression in surgically resected pancreatic adenosquamous carcinoma (PASC) samples. Furthermore, the detection rate was also assessed using biopsy cases obtained from endoscopic ultrasound-guided fine needle aspiration (EUS-FNA).

Molecular pathogenesis of pancreatic ductal adenocarcinoma

The statistics are alarming; pancreatic ductal adenocarcinoma (PDA) will be the second leading cause of death amongst all cancers by 2020. More worrisome is that incidence is on the rise, and without more effective cancer control of this disease, the trajectory of the virtually indistinguishable rates of incidence and mortality will remain the reality for years to come. Advances in genomics are beginning to clarify the key issues about the pathogenesis of this aggressive tumour type. New insights into classic pathogenic driver genes, such as KRAS, CDKN2A, TP53 and SMAD4, are portraying alternative roles for these genes beyond their function at the preneoplastic level including metastatic dissemination and chemoresistance. Clinically relevant molecular subtypes have recently emerged, which will aid oncologists in making more informed treatment decisions to improve outcomes in the future. A wealth of data surrounding these issues has been generated over the last 5 years. Below, we attempt to bring readers up to speed on recent research findings in PDA.     

HBXIP protein overexpression predicts the poor prognosis of pancreatic ductal adenocarcinomas

Background: Hepatitis B virus X-interacting protein (HBXIP) is associated with a variety of tumors. The purpose of this study was to investigate the clinicopathological significance of HBXIP expression in pancreatic ductal adenocarcinoma (PDAC) and to explore its potential as a biomarker for PDAC.Methods: Immunohistochemical (IHC) staining was performed on 126 PDAC tissues, 36 paraneoplastic tissues and 22 normal pancreatic tissues. The relationship between high levels of HBXIP expression and pathological features of PDAC patients was evaluated by chi-squared values.Results:The positive rate of HBXIP protein in PDAC tissues was 85.7% (108/126), which was significantly higher than that of adjacent pancreatic tissue (41.7%, 15/36) and normal pancreas (18.2%, 4/22). In addition, strong positive expression of HBXIP was associated with tumor size, positive lymph node metastasis, clinical stage and 80-month overall survival. Patient's age, gender, degree of differentiation, Ki-67 expression index, and calcification were, however, not associated with high levels of HBXIP expression.Conclusions:We present association between HBXIP expression and the pathological features of patients with PDAC.