Prolonged response to liposomal irinotecan in a patient with stage IV pancreatic/bile duct cancer previously treated with FOLFIRINOX and gemcitabine plus nab-paclitaxel.

At 9%, and 2% when diagnosed at advanced stage, the 5-year relative survival rate for pancreatic ductal adenocarcinoma (pdac) is the lowest of any cancer. The currently approved treatment options for metastatic pdac in the United States are folfirinox [irinotecan-fluorouracil (5fu)-leucovorin (lv)-oxaliplatin], gemcitabine-nab-paclitaxel, and liposomal irinotecan plus 5fu-lv. Liposomal irinotecan is a novel formulation of irinotecan encapsulated within a lipid bilayer, which favours local metabolic activation. The napoli-1 trial demonstrated the efficacy of liposomal irinotecan in combination with 5fu and lv for the treatment of advanced pdac after progression on gemcitabine-based chemotherapy. The 1-year survival in those patients was 25%; however, none had had irinotecan-refractory disease before treatment with liposomal irinotecan. Furthermore, the U.S. National Comprehensive Cancer Network guidelines recommend liposomal irinotecan plus 5fu-lv in patients who have received prior fluoropyrimidine-based therapy if no prior irinotecan therapy has been given. Here, we report a male patient with stage iv cancer of pancreas or bile duct (site unconfirmed) who experienced a prolonged (51 weeks) response to liposomal irinotecan plus 5fu-lv despite prior disease progression on irinotecan. Several factors have previously been associated with long-term survival in patients receiving liposomal irinotecan therapy: no prior irinotecan-based chemotherapy, high Karnofsky performance status score, age 65 years or less, serum carbohydrate antigen 19-9 less than 59 U/mL, neutrophil-to-lymphocyte ratio 5 or less, and absence of liver metastasis. The patient in the present report had none of those characteristics indicative of long-term survival, except his age at diagnosis-47 years.

Suppression of the protein tyrosine phosphatase LAR reduces apolipoprotein B secretion by McA-RH7777 rat hepatoma cells.

Apolipoprotein B (apo B) secretion is reduced by insulin in rat hepatocytes. To evaluate possible mechanisms by which insulin action leads to inhibition of apo B secretion, we evaluated the effect of suppression of the protein-tyrosine phosphatase LAR on apo B secretion by McA-RH7777 (McA) rat hepatoma cells. A reduction in cellular LAR levels was accomplished by stable transfection of McA cells with LAR antisense cDNA. Previous studies indicate that LAR-antisense transfectants demonstrate increased insulin receptor signaling. In current studies, reduced LAR expression results in a 60% to 70% reduction in apo B secretion compared with null vector control. The reduction in apo B secretion correlated with a significant decrease in cellular apo B mRNA levels. Results suggests there is a relationship of protein tyrosine phosphorylation with regulation of apo B mRNA abundance in McA cells.