Relationship between nuclear morphometry, DNA content and resectability of pancreatic cancer

Prognostic significance of DNA cytometry for adjuvant therapy response in pancreatic cancer

BACKGROUND AND OBJECTIVES

The continuous progress in treatment options for pancreatic adenocarcinoma has lead to a re-evaluation of prognostic markers. In this study the prognostic relevance of DNA Index and classical histopathological parameters with regard to disease-free (DFS) and overall survival (OS) was analyzed within the CONKO-001 patient population.

METHODS

One hundred forty three fresh-frozen paraffin-embedded tissue samples of the resected tumor specimen of the CONKO-001 patient population were available for DNA index analysis to evaluate its impact on patient outcome.

RESULTS

Median DFS (7.3 vs. 14.3 months; P = 0.004) and median OS (16.6 vs. 29.2 months; P = 0.011) were significantly decreased in patients with a high DNA index (>1.4). Multivariate analysis revealed both DNA index (DFS: P = 0.002; OS: P = 0.019) and tumor grading (DFS: P = 0.004; OS: P = 0.004) as individual prognostic markers for DFS and OS. The following prognostic subgroups were identified: good (low DNA Index + G1/2 tumor grading), intermediate (low DNA Index + G3 tumor grading or high DNA Index + G1/2 tumor grading), poor (high DNA Index + G3 tumor grading).

CONCLUSION

The DNA index/tumor grading constellation may serve as a helpful guide for personalized treatment recommendations for adjuvant therapy of patients with pancreatic adenocarcinoma.

Ploidy and DNA index as prognostic factors in resected pancreatic ductal adenocarcinoma - a review of the literature

In Poland, pancreatic cancer is the seventh most common cause of cancer-related death amongst men and the sixth amongst women. Pancreatic cancer has an extremely poor prognosis. Radical surgery still remains the only way of curing pancreatic cancer, and this is possible to perform in just 20% of cases, i.e. those that present localised disease upon diagnosis. An average survival of ∼20 months post-resection and adjuvant chemotherapy has been observed in 10–15% of patients with tumours limited to the pancreas at the time of presentation. It is necessary to define strong prognostic factors to determine individual treatment and prognosis. In this paper we submit a review of the literature concerning the prognostic impact of the ploidy and the DNA index on the survival of patients who underwent resection of pancreatic ductal adenocarcinoma. However, the presented studies have produced conflicting results. Pancreatic cancer still remains a great challenge in medicine.

Evaluation of DNA ploidy in relation with established prognostic factors in patients with locally advanced (unresectable) or metastatic pancreatic adenocarcinoma: a retrospective analysis

Background

Most patients with ductal pancreatic adenocarcinoma are diagnosed with locally advanced (unresectable) or metastatic disease. The aim of this study was to evaluate the prognostic significance of DNA ploidy in relation with established clinical and laboratory variables in such patients.

Methods

Two hundred and twenty six patients were studied retrospectively. Twenty two potential prognostic variables (demographics, clinical parameters, biochemical markers, treatment modality) were examined.

Results

Mean survival time was 38.41 weeks (95% c.i.: 33.17–43.65), median survival 27.00 weeks (95% c.i.: 23.18–30.82). On multivariate analysis, 10 factors had an independent effect on survival: performance status, local extension of tumor, distant metastases, ploidy score, anemia under epoetin therapy, weight loss, pain, steatorrhoea, CEA, and palliative surgery and chemotherapy. Patients managed with palliative surgery and chemotherapy had 6.7 times lower probability of death in comparison with patients without any treatment. Patients with ploidy score > 3.6 had 5.0 times higher probability of death in comparison with patients with ploidy score < 2.2 and these with ploidy score 2.2–3.6 had 6.3 times higher probability of death in comparison with patients with ploidy score < 2.2.

Conclusion

According to the significance of the examined factor, survival was improved mainly by the combination of surgery and chemotherapy, and the presence of low DNA ploidy score.

Computational framework for simulating fluorescence microscope images with cell populations

Fluorescence microscopy combined with digital imaging constructs a basic platform for numerous biomedical studies in the field of cellular imaging. As the studies relying on analysis of digital images have become popular, the validation of image processing methods used in automated image cytometry has become an important topic. Especially, the need for efficient validation has arisen from emerging high-throughput microscopy systems where manual validation is impractical. We present a simulation platform for generating synthetic images of fluorescence-stained cell populations with realistic properties. Moreover, we show that the synthetic images enable the validation of analysis methods for automated image cytometry and comparison of their performance. Finally, we suggest additional usage scenarios for the simulator. The presented simulation framework, with several user-controllable parameters, forms a versatile tool for many kinds of validation tasks, and is freely available at http://www.cs.tut.fi/sgn/csb/simcep.

Vav promotes differentiation of human tumoral myeloid precursors

Vav is one of the genetic markers that correlate with the differentiation of hematopoietic cells. In T and B cells, it appears crucial for both development and functions, while, in non-lymphoid hematopoietic cells, Vav seems not involved in cell maturation, but rather in the response of mature cells to agonist-dependent proliferation and phagocytosis. We have previously demonstrated that the amount and the tyrosine phosphorylation of Vav are up-regulated in both whole cells and nuclei of tumoral promyelocytes induced to granulocytic maturation by ATRA and that tyrosine-phosphorylated Vav does not display any ATRA-induced GEF activity but contributes to the regulation of PI 3-K activity. In this study, we report that Vav accumulates in nuclei of ATRA-treated APL-derived cells and that the down-modulation of Vav prevents differentiation of tumoral promyelocytes, indicating that it is a key molecule in ATRA-dependent myeloid maturation. On the other hand, the overexpression of Vav induces an increased expression of surface markers of granulocytic differentiation without affecting the maturation-related changes of the nuclear morphology. Consistent with an effect of Vav on the transcriptional machinery, array profiling shows that the inhibition of the Syk-dependent tyrosine phosphorylation of Vav reduces the number of ATRA-induced genes. Our data support the unprecedented notion that Vav plays crucial functions in the maturation process of myeloid cells, and suggest that Vav can be regarded as a potential target for the therapeutic treatment of myeloproliferative disorders.

Expression of MGMT, hMLH1 and hMSH2 and its clinopathological significance in pancreatic carcinoma tissues

AIM: To study the expression of MGMT, hMLH₁ and hMSH₂ and their clinicopathological significances in the tissues of chronic pancreatitis and pancreatic adenocarcinoma.

METHODS: The expression levels of MGMT, hMLH₁ and hMSH₂ were assayed by immunohistochemical method of avidin-biotin complex on the formalin-fixed and routinely paraffin-embedded sections of surgical resected specimen with chronic pancreatitis (n = 10) and pancreatic carcinoma (n = 51).

RESULTS: The positive rates and the scores of MGMT, hMLH₁ and hMSH₂ were significantly higher in chroinic pancreatitis than those of pancreatic carcinoma (MGMT: 100.0% vs 39.2%,3.8±0.8 vs 1.8±1.4; hMLH1: 100.0% vs 45.1%, 3.8±1.0 vs 1.7±1.6; hMSH2: 90.0% vs 50.9%, 3.5±0.9 vs 1.9±1.7). The positive rates and the scores of MGMT, hMLH₁ and hMSH₂ were significantly higher in well-differentiated adenocarcinomas than those of poorly differentiated adenocarcinomas (P < 0.05 or P < 0.01). The positive rates and the scores of MGMT, hMLH₁ and hMSH₂ were higher in metastasis-free cases than those of ones with metastasis, but no statistic difference was found (P>0.05). There was also no difference among the expression of three proteins and the other clinicopathological characteristics of pancreatic carcinoma.

CONCLUSION: The expression of MGMT, hMLH₁ or hMSH₂ may be related to the carcinogenesis and progression, and have inhibifory effects on the carcinogenesis and progression of pancreatic carcinoma.