UC for 45 minutes. Cells were then washed with 4uC medium and fixed in 3 PFA in PBS. For analysis of surface vs internalised CTLA-4, CHO cells expressing CTLA-4 chimeras were incubated at 37uC withAuthor ContributionsConceived and designed the experiments: SK OSQ DMS. Performed the experiments: SK. Analyzed the data: SK OSQ DMS. Wrote the paper: SK OSQ DMS.CTLA-4 Trafficking
Pancreatic ductal adenocarcinoma (PDAC) is the most fatal form of pancreatic malignancy with a 5 year survival of less than 4 [1,2]. 1676428 Tumor heterogeneity, lack of early detection methods and refractoriness to conventional chemotherapy all contribute to the poor outcome [2]. Surgical resection has limited potential for cure, with less than 20 of patients eligible for surgery with curative intent, due to local spread or metastasis [3]. PDAC is thought to Met-Enkephalin site develop from PanIN lesions (pancreatic intraepithelial neoplasia) through progressive accumulation of somatic alterations in critical genes [4,5]. Despite a repertoire of information, studies linking somatic alterations in PDAC with patient survival are lacking. Over the years somatic mutations have been shown to be legitimate targets for anti-cancer drugs because of casual relationship with tumor formation and maintenance [6]. Histological indistinct tumors, based on the mutational profiles arereported to be differentially amenable to chemotherapeutics [7]. Specific chemotherapeutics, based 
on mutational status, in colorectal, lung, melanoma and other cancer types are already part of cancer treatments [8?2]. Despite KRAS being the most frequently mutated oncogene in pancreatic cancer with a reported frequency ranging between 20 and 100 , it has not been so far utilized in categorization of tumors for clinical purposes [13]. Though, some previous reports have suggested association of KRAS mutations in resected pancreatic cancers with prognosis [14,15]. Most of the earlier reports on KRAS mutations in pancreatic cancer were based on relatively small tumor numbers that lacked statistical power to determine association with the disease outcome. In order to address the issue of frequency of KRAS mutation in pancreatic cancer and impact of those mutations on disease outcome, we have in this study included a series of fully characterized 171 pancreatic tumors with complete patient data.Somatic Mutations in Pancreatic CancerResultsThe 163 patients with malignant tumors in this study comprised the following: i) 143 ductal adeno94-09-7 carcinomas that also included 5 adenosquamous and 4 anaplastic undifferentiated variants, ii) 16 rare carcinomas that were comprised of 2 acinar cell carcinomas, 2 (microcystic) tubulo-papillary carcinomas, 9 intraductal papillary mucinous neoplasm (IPMN, invasive type), 2 solid pseudopapillary neoplasms (Frantz tumors) and 1 cystadenocarcinoma, and iii) 4 papillary (ampulla of Vater) carcinomas. The non-malignant group was composed of 4 benign lesions in the form of serous cystic adenomas (SCA) and premalignant lesions in the form of 1 mucinous cystic neoplasm (MCN) and 3 non-invasive IPMN (Table 1 and Table S3). All patients except nine received standard Gemcitabine treatment. Out of remaining nine patients, eight received 5-fluorouracil/folinic acid and one patient received 5fluorouracil and interferon-alpha together with radiation therapy (Table S3). Mutation detection for KRAS gene was standardized using DNA from cell lines with known KRAS mutation. The sensitivity of SSCP, determined by titration.UC for 45 minutes. Cells were then washed with 4uC medium and fixed in 3 PFA in PBS. For analysis of surface vs internalised CTLA-4, CHO cells expressing CTLA-4 chimeras were incubated at 37uC withAuthor ContributionsConceived and designed the experiments: SK OSQ DMS. Performed the experiments: SK. Analyzed the data: SK OSQ DMS. Wrote the paper: SK OSQ DMS.CTLA-4 Trafficking
Pancreatic ductal adenocarcinoma (PDAC) is the most fatal form of pancreatic malignancy with a 5 year survival of less than 4 [1,2]. 1676428 Tumor heterogeneity, lack of early detection methods and refractoriness to conventional chemotherapy all contribute to the poor outcome [2]. Surgical resection has limited potential for cure, with less than 20 of patients eligible for surgery with curative intent, due to local spread or metastasis [3]. PDAC is thought to develop from PanIN lesions (pancreatic intraepithelial neoplasia) through progressive accumulation of somatic alterations in critical genes [4,5]. Despite a repertoire of information, studies linking somatic alterations in PDAC with patient survival are lacking. Over the years somatic mutations have been shown to be legitimate targets for anti-cancer drugs because of casual relationship with tumor formation and maintenance [6]. Histological indistinct tumors, based on the mutational profiles arereported to be differentially amenable to chemotherapeutics [7]. Specific chemotherapeutics, based on mutational status, in colorectal, lung, melanoma and other cancer types are already part of cancer treatments [8?2]. Despite 
KRAS being the most frequently mutated oncogene in pancreatic cancer with a reported frequency ranging between 20 and 100 , it has not been so far utilized in categorization of tumors for clinical purposes [13]. Though, some previous reports have suggested association of KRAS mutations in resected pancreatic cancers with prognosis [14,15]. Most of the earlier reports on KRAS mutations in pancreatic cancer were based on relatively small tumor numbers that lacked statistical power to determine association with the disease outcome. In order to address the issue of frequency of KRAS mutation in pancreatic cancer and impact of those mutations on disease outcome, we have in this study included a series of fully characterized 171 pancreatic tumors with complete patient data.Somatic Mutations in Pancreatic CancerResultsThe 163 patients with malignant tumors in this study comprised the following: i) 143 ductal adenocarcinomas that also included 5 adenosquamous and 4 anaplastic undifferentiated variants, ii) 16 rare carcinomas that were comprised of 2 acinar cell carcinomas, 2 (microcystic) tubulo-papillary carcinomas, 9 intraductal papillary mucinous neoplasm (IPMN, invasive type), 2 solid pseudopapillary neoplasms (Frantz tumors) and 1 cystadenocarcinoma, and iii) 4 papillary (ampulla of Vater) carcinomas. The non-malignant group was composed of 4 benign lesions in the form of serous cystic adenomas (SCA) and premalignant lesions in the form of 1 mucinous cystic neoplasm (MCN) and 3 non-invasive IPMN (Table 1 and Table S3). All patients except nine received standard Gemcitabine treatment. Out of remaining nine patients, eight received 5-fluorouracil/folinic acid and one patient received 5fluorouracil and interferon-alpha together with radiation therapy (Table S3). Mutation detection for KRAS gene was standardized using DNA from cell lines with known KRAS mutation. The sensitivity of SSCP, determined by titration.