A pancreatic carcinoma cell line, AsPC-1, underwent apoptosis in vitro when heat-treated for 60 min at 43 degrees C. Apoptotic AsPC-1 cells liberated a monocyte chemotactic factor into the culture supernatant 24 to 30 h after the heat-treatment. This factor was immunologically identified as the cross-linked homodimer of S19 ribosomal protein (RP S19), since the majority of the chemotactic activity was absorbed by both anti--RP S19 rabbit antibodies and an anti--isopeptide bond monoclonal antibody immobilized on agarose beads. Intracellular transglutaminase activity increased during the apoptotic process, reaching the peak strength between 18 and 24 h after the heat-treatment. A recombinant RP S19 acquired the monocyte chemotactic capacity when incubated with the apoptotic cell extract obtained at the 18th hour. The chemotactic activity acquirement as well as the transglutaminase activity were blocked by treatment of the extract with anti--type II transglutaminase rabbit antibodies. When the recombinant RP S19 was treated with an authentic type II transglutaminase, the dimerization of RP S19 concomitant with the generation of the monocyte chemotactic activity was observed. Peptide-map analyses involving amino acid sequencing demonstrated that the inter-molecular isopeptide bond was heterogeneous: Gln12 or Gln137 and Lys29 or Lys122 were cross-linked. Site-directed mutagenic analysis indicated that the cross-linking of Gln137, but not other residues such as Gln12, Lys29, and Lys122, was essential for expression of the chemotactic activity.
LAT for HCCs (even those less than 3 cm in diameter) adjacent less than 5 mm to the main or sectional portal vein possibly promotes intrahepatic dissemination.
Although preoperative FOLFOX administration in patients with colorectal liver metastases caused macroscopic blue liver, microscopic sinusoidal dilatation in the liver parenchyma, and a significant decrease in liver function, there was no increase in the morbidity and mortality rates, in comparison to findings in patients without preoperative chemotherapy.
The characteristic histological feature of pancreatic mucinous cystic neoplasm (MCN) is ovarian-like stroma (OS) underlying the epithelium and existence of estrogen receptors and progesterone receptors in the nucleus of OS. We experienced a case of pancreatic MCN which was activated during pregnancy and confirmed the existence of estrogen receptors and progesterone receptors. In cases with potential factors for malignancy, surgical resection of MCN may be needed during pregnancy. On the other hand, in cases without these, as female sex hormones may have an influence on the behavior of pancreatic MCN during pregnancy, the timing of surgery should be decided on a case-by-case basis, taking into consideration the status of the malignancy, the stage of the pregnancy, and the condition of the mother and fetus.
We report a novel 3-dimensional model for visualizing tumor cell migration across a nylon mesh-supported gelatin matrix. To visualize migration across these model barriers, cell proteolytic activity of the pericellular matrix was detected using Bodipy-BSA (fluorescent upon proteolysis) and DQ collagen (fluorescent upon collagenase activity). For 3-dimensional image reconstruction, multiple optical images at sequential z axis positions were deconvoluted by computer analysis. Specificity was indicated using well-known inhibitors. Using these fluorescent proteolysis markers and imaging methods, we have directly demonstrated proteolytic and collagenolytic activity during tumor cell invasion. Moreover, it is possible to visualize migratory pathways followed by tumor cells during matrix invasion. Using cells of differing invasive potentials (uPAR-negative T-47D wild-type and uPAR-positive T-47D A2--1 cells), we show that the presence of the T-47D-A2--1 cells facilitates the entry of T-47D wild-type cells into the matrix. In some cases, wild-type cells follow T-47D A2--1 cells into the matrix whereas other T-47D-wild-type cells appear to enter without the direct intervention of T-47D A2--1 cells. Thus, we have developed a new 3-dimensional model of tumor cell invasion, demonstrated protein and collagen disruption, mapped the pathways followed by tumor cells during migration through an extracellular matrix, and illustrated cross-talk among tumor cell populations during invasion.
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