The prognostic effect of resection margin status following pancreatoduodenectomy for pancreatic ductal adenocarcinoma (PDAC) remains controversial, even with the implementation of standardized ...pathological assessment. We therefore investigated the impact of resection margin (RM) status and RM distance in curative resected PDAC on overall survival (OS), disease-free survival (DFS) and recurrence.
108 patients were retrieved from a prospectively maintained database of a certified pancreatic cancer center. Distribution and relationships between circumferential resection margin (CRM) involvement (CRM≤1mm; CRM>1mm; CRM≥2mm) and their prognostic impact on OS and DFS were assessed using Kaplan-Meier statistics and the Log-Rank test. Multivariate logistic regression was used explain the development of a recurrence 12 months after surgery.
63 out of 108 patients had medial RM and 32 posterior RM involvement. There was no significant difference in OS and DFS between CRM≤1mm and CRM>1mm resections. Clearance at the medial margin of ≥2mm had an impact on OS and DFS, (RM≥2mm vs. RM<2mm: median OS 29.8 vs 16.8 months, median DFS 19.6 vs. 10.3 months). Multivariate analysis demonstrated that age, medial RM ≥2mm, lymph node status and chemotherapy were prognostic factors for OS and DFS. Posterior RM had no influence on OS or DFS.
Not all RM seem to have the same impact on OS and DFS, and a clearance of 1mm for definition of a negative RM (i.e. CRM>1mm) seems not sufficient. Future studies should include more patients to stratify for potential confounders we could not account for.
This study was registered with the German Clinical Trials Registry (reference number DRKS0017425).
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
MicroRNAs (miRNAs: short non-coding RNAs) are emerging as a class of potential novel tumor markers, as their dysregulation is being increasingly reported in various types of cancers. In the present ...study, we investigated the transcription status of miRNA-148a (miR-148a) in human pancreatic ductal adenocarcinoma (PDAC) and its role in the regulation of the dual specificity protein phosphatase CDC25B. We observed that miR-148a exhibited a significant 4-fold down-regulation in PDAC as opposed to normal pancreatic ductal cells. In addition, we observed that stable lentiviral-mediated overexpression of miR-148a in the pancreatic cancer cell line IMIM-PC2, inhibited tumor cell growth and colony formation. Furthermore, CDC25B was identified as a potential target of miR-148a by in silico analysis using PicTar, Targetscan and miRanda in conjunction with gene ontology analysis. The proposed interaction between miR-148a and the 3′ untranslated region (UTR) of CDC25B was verified by in-vitro luciferase assays. We demonstrate that the activity of a luciferase reporter containing the 3′UTR of CDC25B was repressed in the presence of miR-148a mimics, confirming that miR-148a targets the 3′UTR of CDC25B. Finally, CDC25B was down-regulated at the protein level in miR-148a overexpressing IMIM-PC2-cells, and in transiently transfected pancreatic cell lines (as detected by Western blot analysis), as well as in patient tumor samples (as detected by immunohistochemistry). In summary, we identified CDC25B as a novel miR-148a target which may confer a proliferative advantage in PDAC.
The microRNA encoding genes
miR-34a
and
miR-34b/c
represent direct p53 target genes and possess tumor suppressive properties as they mediate apoptosis, cell cycle arrest, and senescence. We ...previously reported that the
miR-34a
gene is subject to epigenetic inactivation by CpG methylation of its promoter region in primary prostate cancer and melanomas, and in 110 different cancer cell lines of diverse origin. Here we analyzed the methylation status of
miR-34a
and
miR-34b/c
in additional primary tumors of divergent sites. We found methylation of
miR-34a
or
miR-34b/c
in formalin-fixed, paraffin-embedded (FFPE) tumor samples from 178 patients with the following frequencies: colorectal cancer (74%
miR-34a
, 99%
miR-34b/c
;
n
= 114), pancreatic cancer (64%, 100%;
n
= 11), mammary cancer (60%, 90%;
n
= 10), ovarian cancer (62%, 69%;
n
= 13), urothelial cancer (71%, 57%;
n
= 7), and renal cell cancer (58%, 100%;
n
= 12). Furthermore, soft tissue sarcomas showed methylation of
miR-34
gene promoters in FFPE samples (64%, 45%;
n
= 11), in explanted, cultured cells (53%, 40%;
n
= 40), and in frozen tissue samples (75%, 75%,
n
= 8). In the colorectal cancer samples a statistically significant correlation of
miR-34a
methylation and the absence of p53 mutation was detected. With the exception of sarcoma cell lines, the inactivation of
miR-34a
and
miR-34b/c
was concomitant in most cases. These results show that
miR-34
inactivation is a common event in tumor formation, and suggest that CpG methylation of
miR-34a
and
miR-34-b/c
may have diagnostic value. The mutual exclusiveness of
miR-34a
methylation and p53 mutation indicates that
miR-34a
inactivation may substitute for loss of p53 function in cancer.
Pancreatic ductal adenocarcinoma (PDAC) is known for its poor prognosis resulting from being diagnosed at an advanced stage. Accurate early diagnosis and new therapeutic modalities are therefore ...urgently needed. MicroRNAs (miRNAs), considered a new class of biomarkers and therapeutic targets, may be able to fulfill those needs. Combining tissue microdissection with global miRNA array analyses, cell type‐specific miRNA expression profiles were generated for normal pancreatic ductal cells, acinar cells, PDAC cells derived from xenografts and also from macrodissected chronic pancreatitis (CP) tissues. We identified 78 miRNAs differentially expressed between ND and PDAC cells providing new insights into the miRNA‐driven pathophysiological mechanisms involved in PDAC development. Having filtered miRNAs which are upregulated in the three pairwise comparisons of PDAC vs. ND, PDAC vs. AZ and PDAC vs. CP, we identified 15 miRNA biomarker candidates including miR‐135b. Using relative qRT‐PCR to measure miR‐135b normalized to miR‐24 in 75 FFPE specimens (42 PDAC and 33 CP) covering a broad range of tumor content, we discriminated CP from PDAC with a sensitivity and specificity of 92.9% 95% CI=(80.5, 98.5) and 93.4% 95% CI=(79.8, 99.3), respectively. Furthermore, the area under the curve (AUC) value reached of 0.97 was accompanied by positive and negative predictive values of 95% and 91%, respectively. In conclusion, we report pancreatic cell‐specific global miRNA profiles, which offer new candidate miRNAs to be exploited for functional studies in PDAC. Furthermore, we provide evidence that miRNAs are well‐suited analytes for development of sensitive and specific aid‐in‐diagnosis tests for PDAC.
MicroRNAs (miRNAs) are RNA molecules that are involved in the regulation of many cellular processes, including those related to human cancers. The aim of this study was to determine, as a proof of ...principle, whether specific candidate miRNAs could be detected in fine-needle aspirate (FNA) biopsies of pancreatic ductal adenocarcinoma (PDAC) and could accurately differentiate malignant from benign pancreatic tissues.
We used TaqMan(R) assays to quantify miRNA levels in FNA samples collected in RNARetain (n = 16) and compared the results with a training set consisting of frozen macrodissected pancreatic samples (n = 20).
Quantitative reverse-transcription PCR analysis confirmed that miRNA levels are affected in PDAC FNAs and correlate well with the changes observed in the training set of frozen pancreatic samples. Analysis of the amounts produced for a few specific miRNAs enabled identification of PDAC samples. The combination of miR-196a and miR-217 biomarkers further improved the ability to distinguish between healthy tissue, PDAC, and chronic pancreatitis in the training set (P = 8.2 x 10(-10)), as well as segregate PDAC FNA samples from other FNA samples (P = 1.1 x 10(-5)). Furthermore, we showed that miR-196a production is likely specific to PDAC cells and that its incidence paralleled the progression of PDAC.
To the best of our knowledge, this study is the first to evaluate the diagnostic potential of miRNAs in a clinical setting and has shown that miRNA analysis of pancreatic FNA biopsy samples can aid in the pathologic evaluation of suspicious cases and may provide a new strategy for improving the diagnosis of pancreatic diseases.
Improved non‐invasive strategies for early cancer detection are urgently needed to reduce morbidity and mortality. Non‐coding RNAs, such as microRNAs and small nucleolar RNAs, have been proposed as ...biomarkers for non‐invasive cancer diagnosis. Analyzing serum derived from nude mice implanted with primary human pancreatic ductal adenocarcinoma (PDAC), we identified 15 diagnostic microRNA candidates. Of those miR‐1246 was selected based on its high abundance in serum of tumor carrying mice. Subsequently, we noted a cross reactivity of the established miR‐1246 assays with RNA fragments derived from U2 small nuclear RNA (RNU2‐1). Importantly, we found that the assay signal discriminating tumor from controls was derived from U2 small nuclear RNA (snRNA) fragments (RNU2‐1f) and not from miR‐1246. In addition, we observed a remarkable stability of RNU2‐1f in serum and provide experimental evidence that hsa‐miR‐1246 is likely a pseudo microRNA. In a next step, RNU2‐1f was measured by qRT‐PCR and normalized to cel‐54 in 191 serum/plasma samples from PDAC and colorectal carcinoma (CRC) patients. In comparison to 129 controls, we were able to classify samples as cancerous with a sensitivity and specificity of 97.7% 95% CI = (87.7, 99.9) and 90.6% 95% CI = (80.7, 96.5), respectively area under the ROC curve 0.972. Of note, patients with CRC were detected with our assay as early as UICC Stage II with a sensitivity of 81%. In conclusion, this is the first report showing that fragments of U2 snRNA are highly stable in serum and plasma and may serve as novel diagnostic biomarker for PDAC and CRC for future prospective screening studies.
What's new?
Non‐coding RNAs hold significant promise as biomarkers for noninvasive early cancer detection, but their utility has not yet been demonstrated. Here, fragments of the non‐coding U2 small nuclear RNA (RNU2) were found to be highly preserved and abundant in serum and plasma from pancreatic ductal adenocarcinoma and colorectal cancer patients. Reliable detection of the fragments, particularly for UICC stage II colorectal cancers, suggests that RNU2 may be a valuable screening marker for these cancers.
Inactivating mutations of SMAD4 are frequent in metastatic colorectal carcinomas. In previous analyses, we were able to show that restoration of Smad4 expression in Smad4-deficient SW480 human colon ...carcinoma cells was adequate to suppress tumorigenicity and invasive potential, whereas in vitro cell growth was not affected. Using this cellular model system, we searched for new Smad4 targets comparing nuclear subproteomes derived from Smad4 re-expressing and Smad4 negative SW480 cells.
High resolution two-dimensional (2D) gel electrophoresis was applied to identify novel Smad4 targets in the nuclear subproteome of Smad4 re-expressing SW480 cells. The identified candidate protein Keratin 23 was further characterized by tandem affinity purification. Immunoprecipitation, subfractionation and immunolocalization studies in combination with RNAi were used to validate the Keratin 23-14-3-3ε interaction.
We identified keratins 8 and 18, heat shock proteins 60 and 70, plectin 1, as well as 14-3-3ε and γ as novel proteins present in the KRT23-interacting complex. Co-immunoprecipitation and subfractionation analyses as well as immunolocalization studies in our Smad4-SW480 model cells provided further evidence that KRT23 associates with 14-3-3ε and that Smad4 dependent KRT23 up-regulation induces a shift of the 14-3-3ε protein from a nuclear to a cytoplasmic localization.
Based on our findings we propose a new regulatory circuitry involving Smad4 dependent up-regulation of KRT23 (directly or indirectly) which in turn modulates the interaction between KRT23 and 14-3-3ε leading to a cytoplasmic sequestration of 14-3-3ε. This cytoplasmic KRT23-14-3-3 interaction may alter the functional status of the well described 14-3-3 scaffold protein, known to regulate key cellular processes, such as signal transduction, cell cycle control, and apoptosis and may thus be a previously unappreciated facet of the Smad4 tumor suppressive circuitry.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
CCR7 expression on tumor cells promotes lymphatic spread in several malignant tumors. However, a comprehensive characterization of the CCL19/CCL21–CCR7 axis in pancreatic ductal adenocarcinoma ...(PDAC), which is known for its high rates of lymph‐node metastases, is still lacking. CCR7 mRNA and CCR7 protein were found to be expressed in spheroid cultures of all six examined PDAC cell lines. In migration assays, CCR7 expressing PDAC cells showed enhanced migration toward CCL19 and CCL21, the two ligands of CCR7. In an orthotopic nude mouse model, CCR7‐transfected PT45P1 cells gave rise to significantly larger tumors and showed a higher frequency of lymph vessel invasion and lymph‐node metastases than mock‐transfected cells. In an analysis using quantitative real‐time PCR, CCR7 showed fourfold overexpression in microdissected PDAC cells compared to normal duct cells. Moderate‐to‐strong immunohistochemical CCR7 expression, found in 58 of 121 well‐characterized human PDACs, correlated with high rates of lymph vessel invasion. Conversely, PDACs completely lacking CCR7 expression showed only low rates of lymph vessel invasion and lymph‐node metastases. The evaluation of CCL21 expression by immunofluorescence staining revealed a significant upregulation of CCL21 in peritumoral and intratumoral lymph vessels compared to lymph vessels in disease‐free pancreata. In conclusion, our study revealed strong evidence that lack of CCR7 impairs the metastatic potential of PDAC. Lymph vessel invasion by CCR7 expressing PDAC cells may be additionally enhanced by upregulation of CCL21 in tumor‐associated lymph vessels, representing a previously unknown factor of lymphatic spread.
Background & Aims Endoscopic ultrasound–guided fine-needle aspiration (EUS-FNA) in combination with cytopathology is the optimal method for diagnosis and staging of pancreatic ductal adenocarcinoma ...(PDAC) and other pancreatic lesions. Its clinical utility, however, can be limited by high rates of indeterminate or false-negative results. We aimed to develop and validate a microRNA (miRNA)-based test to improve preoperative detection of PDAC. Methods Levels of miRNAs were analyzed in a centralized clinical laboratory by relative quantitative polymerase chain reaction in 95 formalin-fixed paraffin-embedded specimens and 228 samples collected by EUS-FNA during routine evaluations of patients with solid pancreatic masses at 4 institutions in the United States, 1 in Canada, and 1 in Poland. Results We developed a 5-miRNA expression classifier, consisting of MIR24, MIR130B, MIR135B, MIR148A, and MIR196, that could identify PDAC in well-characterized, formalin-fixed, paraffin-embedded specimens. Detection of PDAC in EUS-FNA samples increased from 78.8% by cytology analysis alone (95% confidence interval, 72.2%–84.5%) to 90.8% when combined with miRNA analysis (95% confidence interval, 85.6%–94.5%). The miRNA classifier correctly identified 22 additional true PDAC cases among 39 samples initially classified as benign, indeterminate, or nondiagnostic by cytology. Cytology and miRNA test results each were associated significantly with PDAC ( P < .001), with positive predictive values greater than 99% (95% confidence interval, 96%–100%). Conclusions We developed and validated a 5-miRNA classifier that can accurately predict which preoperative pancreatic EUS-FNA specimens contain PDAC. This test might aid in the diagnosis of pancreatic cancer by reducing the number of FNAs without a definitive adenocarcinoma diagnosis, thereby reducing the number of repeat EUS-FNA procedures.
Pancreatic cancer (PC) is a lethal disease with a poor prognosis. It is typically asymptomatic and therefore most often diagnosed at an advanced stage. A primary unresectable PC can become resectable ...in case of tumor regression turning palliative into neoadjuvant therapy. We present a 67-year old female patient who was diagnosed with a locally advanced adenocarcinoma of the pancreatic head. After receiving palliative intended chemotherapy with the FOLFIRINOX regimen, staging computed tomography revealed local resectability of the pancreatic head tumor. The patient underwent an uneventful total pancreatectomy. Pathohistological investigation revealed a pathologic complete response (pCR). pCR after FOLFIRINOX treatment in primary unresectable PC is extremely rare. It might enable surgical resection and can increase the survival rate.
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