Project description:Background: With less than a 5% survival rate pancreatic adenocarcinoma (PDAC) is almost uniformly lethal. In order to make a significant impact on survival of patients with this malignancy, it is necessary to diagnose the disease early, when curative surgery is still possible. Detailed knowledge of the natural history of the disease and molecular events leading to its progression is therefore critical. Methods and Findings: We have analysed the precursor lesions, PanINs, from prophylactic pancreatectomy specimens of patients from four different kindreds with high risk of familial pancreatic cancer who were treated for histologically proven PanIN-2/3. Thus, the material was procured before pancreatic cancer has developed, rather than from PanINs in a tissue field that already contains cancer. Genome-wide transcriptional profiling using such unique specimens was performed. Bulk frozen sections displaying the most extensive but not microdissected PanIN-2/3 lesions were used in order to obtain the holistic view of both the precursor lesions and their microenvironment. A panel of 76 commonly dysregulated genes that underlie neoplastic progression from normal pancreas to PanINs and PDAC were identified. In addition to shared genes some differences between the PanINs of individual families as well as between the PanINs and PDACs were also seen. This was particularly pronounced in the stromal and immune responses. Conclusions: Our comprehensive analysis of precursor lesions without the invasive component provides the definitive molecular proof that PanIN lesions beget cancer from a molecular standpoint. We demonstrate the need for accumulation of transcriptomic changes during the progression of PanIN to PDAC, both in the epithelium and in the surrounding stroma. An identified 76-gene signature of PDAC progression presents a rich candidate pool for the development of early diagnostic and/or surveillance markers as well as potential novel preventive/therapeutic targets for both familial and sporadic pancreatic adenocarcinoma. Gene expression of 13 PanIN samples was compared to profiling data of whole biopsies from normal donor pancreas (N1 to 4, two replicated samples) and sporadic PDAC (PDAC1 to 6).Ttwo PDAC samples (PDAC 3 and 4) and a replicate of one normal specimen (N4) were removed during the hybridisation quality assessment.

Project description:We obtained peripheral blood samples for women from Utah (USA) and Ontario (Canada) who had a family history of breast cancer (or did not), who carried a BRCA1/2 mutation (or did not), and who had developed breast cancer (or had not). We classified the women into two groups: [1] those who had a family history of breast cancer (irrespective of BRCA1/2 mutation status) and had developed an early-onset breast tumor and [2] those who had a family history of breast cancer but had not developed a breast tumor or who did not have a family history of breast cancer (some of whom had developed sporadic breast cancer and and others who had not). We then used machine-learning methods to assess how well we could classify these women into either group. The Utah samples served as a training set, and the Ontario samples served as an independent validation set from a geographically distinct population. For the Utah cohort, there are 124 samples total: 16 who had a family history of breast cancer and carried a BRCA mutation and had developed breast cancer, 23 with a family history of breast cancer but did not carry a BRCA1/2 mutation and had developed breast cancer, 22 with a family history of breast cancer and carried a BRCA1/2 mutation but had not developed breast cancer, 22 with a family history of breast cancer but did not carry a BRCA1/2 mutation and had not developed breast cancer, 22 with no family history of breast cancer and had developed breast cancer, and 19 with no family history of breast cancer and had not developed breast cancer. The Ontario cohort included 73 samples: 11 who had a family history of breast cancer and carried a BRCA mutation and had developed breast cancer, 17 with a family history of breast cancer but did not carry a BRCA1/2 mutation and had developed breast cancer, 14 with a family history of breast cancer and carried a BRCA1/2 mutation but had not developed breast cancer, 18 with a family history of breast cancer but did not carry a BRCA1/2 mutation and had not developed breast cancer, 8 with no family history of breast cancer and had developed breast cancer, and 5 with no family history of breast cancer and had not developed breast cancer. 36 of the Ontario samples were scanned and processed at Duke University; the remaining 37 samples were handled at Boston University. The batch-adjustment process was repeated twice independently: [1] all 124 Utah samples were adjusted jointly with the 36 Ontario samples that had been processed at Duke University (set 1) and [2] all 124 Utah samples were adjusted jointly with the 37 Ontario samples that had been processed at Boston University (set 2). This dataset represents set 1.

Project description:Background: With less than a 5% survival rate pancreatic adenocarcinoma (PDAC) is almost uniformly lethal. In order to make a significant impact on survival of patients with this malignancy, it is necessary to diagnose the disease early, when curative surgery is still possible. Detailed knowledge of the natural history of the disease and molecular events leading to its progression is therefore critical. Methods and Findings: We have analysed the precursor lesions, PanINs, from prophylactic pancreatectomy specimens of patients from four different kindreds with high risk of familial pancreatic cancer who were treated for histologically proven PanIN-2/3. Thus, the material was procured before pancreatic cancer has developed, rather than from PanINs in a tissue field that already contains cancer. Genome-wide transcriptional profiling using such unique specimens was performed. Bulk frozen sections displaying the most extensive but not microdissected PanIN-2/3 lesions were used in order to obtain the holistic view of both the precursor lesions and their microenvironment. A panel of 76 commonly dysregulated genes that underlie neoplastic progression from normal pancreas to PanINs and PDAC were identified. In addition to shared genes some differences between the PanINs of individual families as well as between the PanINs and PDACs were also seen. This was particularly pronounced in the stromal and immune responses. Conclusions: Our comprehensive analysis of precursor lesions without the invasive component provides the definitive molecular proof that PanIN lesions beget cancer from a molecular standpoint. We demonstrate the need for accumulation of transcriptomic changes during the progression of PanIN to PDAC, both in the epithelium and in the surrounding stroma. An identified 76-gene signature of PDAC progression presents a rich candidate pool for the development of early diagnostic and/or surveillance markers as well as potential novel preventive/therapeutic targets for both familial and sporadic pancreatic adenocarcinoma.

Dataset Information

Pancreas Registry and High Risk Registry

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets