[Progression from adenocarcinoma to small cell carcinoma of the prostate during endocrinotherapy: a case report].

A 72-year-old man had undergone surgical castration for metastatic prostate cancer (stage D2, the PSA value was 4,300 ng/ml) in September, 1997. He was well clinically for 16 months with undetected level of PSA. However, he presented with general malaise and gross hematuria in May, 1999. After admission to our hospital his condition rapidly deteriorated and he died one week later with respiratory failure. Autopsy revealed extensive involvement of the prostate and bladder by solid tumor with multiple metastases in lungs, liver, spleen, kidneys and bone. Histological examination revealed pure small cell carcinoma of the prostate.

Molecular analysis of multidrug resistance in feline lymphoma cells.

OBJECTIVE: To evaluate the mechanism of multidrug resistance in feline lymphoma cell lines. SAMPLE POPULATION: A feline lymphoma cell line (FT-1) and its adriamycin (ADM)-resistant subline (FT-1/ADM). PROCEDURES: The FT-1 cell line was cultivated in the presence of a gradually increasing concentration of ADM to generate its ADM-resistant subline (FT-1/ADM). Susceptibility of cells from the parental FT-1 cell line and the FT-1/ADM subline to antineoplastic drugs was determined. From the complementary DNA (cDNA) template of FT-1/ADM cells, feline MDR1 cDNA was amplified by use of polymerase chain reaction (PCR) and sequenced. Reverse transcription (RT)-PCR and Western blot analyses were performed to assess expression of the MDR1 gene and P-glycoprotein (P-gp) in FT-1/ADM cells, compared with that in FT-1 cells. RESULTS: A drug sensitivity assay revealed that FT-1/ADM cells were much more resistant to ADM and vincristine than the parental FT-1 cells. The feline MDR7 cDNA amplified by use of PCR was 3,489 base pairs long, corresponding to approximately 90% of the whole open reading frame of human MDR1 cDNA; its amino acid sequence was 91.5, 87.0, and 79.4% identical to that of human MDR1, mouse mdr1a, and mdr1b cDNA, respectively. By RT-PCR analysis, expression of MDR1 messenger RNA was clearly detected in FT-1/ADM cells but not in the parental FT-1 cells. Western blot analysis also revealed the expression of P-gp encoded by the MDR1 gene in FT-1/ADM cells but not in FT-1 cells. CONCLUSIONS: The basic structure of the feline MDR1 gene was essentially the same as that of multidrug-resistance genes of other species. Expression of P-gp appeared to be one of the mechanisms responsible for the development of multidrug resistance in feline lymphoma cell lines in vitro.

Living related liver transplantation: histopathologic analysis of graft dysfunction in 304 patients.

Between June 1990 and August 1997, 304 mainly pediatric patients underwent a total of 311 orthotopic living related liver transplantations (LRLTs) under tacrolimus immunosuppression at Kyoto University Hospital. Congenital biliary atresia was the most common underlying disease. The donor was a parent, and the left lateral segments were used as grafts in most cases. The average number of loci of HLA-A, -B, and -DR mismatches between the donor and the recipient were 2.1. Forty-three transplants were ABO-incompatible. Liver histology at the time of abnormal liver function after transplantation was analyzed. Preservation injury was rare and mild. Acute cellular rejection (ACR) occurred in 36% of transplants during the first 6 months. Average rejection activity index (the Banff schema) was 4.2 and severe rejection was rarely seen. The number of mismatching HLA loci and immunosuppression regimens affected the incidence of ACR. Chronic rejection (CR) occurred in 2% of transplants. Concerning humoral rejection, no hyperacute rejection was seen. However, hepatic artery thrombosis (delayed hyperacute rejection) was seen in an ABO-incompatible transplant. Acute hepatitis, including those related to cytomegalovirus and Epstein-Barr virus, occurred in 17% of transplants. Chronic hepatitis, including hepatitis B and C, developed in 3%. Acute or chronic cholangitis occurred in 16%, and a significantly higher incidence of cholangitis was found in ABO-incompatible transplants. Posttransplantation lymphoproliferative disease developed in 2%. In LRLT, milder preservation injury and less frequent ACR and CR were suggested, probably because of the short cold-ischemia time and the advantages of HLA histocompatibility, respectively.

Molecular cloning and functional expression of feline thrombopoietin.

Feline thrombopoietin (TPO) was molecularly cloned to establish a basis for cytokine therapy of thrombocytopenia in cats. cDNA clones covering the whole coding sequence of feline TPO were isolated from feline liver. The feline TPO cDNA obtained in this study contained an open reading frame encoding 349 amino acid residues. The predicted amino acid sequence of feline TPO shared 78.7, 69.9, 72.9 and 83.0% similarity with sequences of human, murine, rat and canine TPO, respectively. Four cysteine residues and two of four N-glycosylation sites that are conserved among species were also found at the corresponding positions in feline TPO. The feline TPO cDNA fragment encoding the whole amino acid coding region was recloned into an expression vector, and the resulting vector was transfected into 293T cells using the calcium phosphate method. The supernatant of the transfected 293T cells stimulated the proliferation of a human megakaryoblastic leukemia cell line (UT-7/TPO) cells in a dose dependent manner, indicating that the feline TPO cDNA obtained in this study encodes biologically active feline TPO.

Molecular cloning and functional expression of equine interleukin-1 receptor antagonist.

Equine interleukin-1 receptor antagonist (IL-1ra) was molecularly cloned to establish a basis for cytokine therapy of acute and chronic inflammatory diseases in the horse. cDNA clones encoding the whole coding sequence of equine IL-1ra were isolated from equine peripheral blood mononuclear cells (PBMC) that had been stimulated with lipopolysaccharide (LPS). The equine IL-1ra cDNA obtained in this study contained an open reading frame encoding 177 amino acid residues. The predicted amino acid sequence of equine IL-1ra shared 75.7, 75.3 and 76.3% similarity with sequences of human, murine and rabbit IL-1ras, respectively. An N-glycosylation site and five cysteine residues conserved in human, murine and rabbit IL-1ras were also found at the corresponding positions in equine IL-1ra. Recombinant glutathione S-transferase (GST)-equine IL-1ra fusion protein produced by Escherichia coli was purified. This protein was shown to inhibit the cytostatic or cytotoxic activity of IL-1 on A375S2 cells, indicating that the equine IL-1ra cDNA obtained in this study encodes biologically active equine IL-1ra.

Genetic and epigenetic resistance of SL/Ni mice to lymphomas.

The murine spontaneous B lymphoma is etiologically related to the expression of endogenous ecotropic murine leukemia virus (ETV). Although both SL/Kh and SL/Ni mouse strains show a high level of expression of ETV from early in life, the former is a pre-B lymphoma-prone strain and the latter is rather lymphoma-resistant. In order to identify the host background difference related to the lymphomagenesis, we performed a genetic cross study between these two strains. In the reciprocal F1 generation, the length of the lymphoma latent period was slightly but significantly longer in (SL/Ni xSL/Kh)F1 than in (SL/KhxSL/Ni)F1(P < 0.05). The incidence of overall lymphomas and that of acute pre-B lymphomas was lower in (SL/NixSL/Kh)F1 than in (SL/KhxSL/Ni)F1, although the difference was not statistically significant. These observations indicate that an epigenetic maternal resistance mechanism of SL/Ni mice plays a role in the lymphoma resistance. Furthermore, in the backcross combinations without maternal influence of SL/Ni, we observed a genetic mechanism of lymphoma resistance: an SL/Ni-derived recessive lymphoma-resistance gene mapped in the proximal segment of Chr. 4. We named this gene nir-1 (SL/Ni-lymphoma resistance-1). Thus, we have demonstrated epigenetic and genetic mechanisms of lymphoma resistance of the SL/Ni mouse with the high expression of endogenous ETV.

T lymphomagenesis is determined by a dominant host gene thymic lymphoma susceptible mouse-1 (TLSM-1) in mouse models.

Susceptibility to T lymphomas in mice is determined by a number of viral and host genetic factors. We analyzed the types and latent period of lymphomas spontaneously occurring in crosses between AKR/Ms, a T lymphoma-prone mouse strain, and SL/Kh, a pre-B lymphoma-prone strain. The incidence of T lymphomas in the F1 hybrids backcross to SL/Kh as well as F2 generation mice indicated that a dominant host gene thymic lymphoma susceptible mouse-1 (Tlsm-1) of AKR/Ms determined the type of lymphomas to be thymic. Linkage analysis with microsatellite markers assigned Tlsm-1 to the map position 61 cM from centromere of the chromosome 7. Close scrutiny of this region of AKXD recombinant inbred strains for spontaneous T lymphomas revealed the presence of Tlsm-1-like gene most likely between D7MIT71 (map position 62) and D7MIT13 (map position 70). On the other hand, a SL/Kh-derived recessive allele at a major histocompatibility complex (MHC)-linked locus accelerated development of both T and B lymphomas.

Genetic predisposition to pre-B lymphomas in SL/Kh strain mice.

Genetic predisposition of SL/Kh mice to spontaneous pre-B lymphomas was investigated in crosses between SL/Kh and NFS/N, another inbred strain of mice lacking endogenous ecotropic provirus and spontaneous lymphoma. (SL/Kh x NFS/N) F1 hybrids developed lymphomas similar to those in SL/Kh but at a lower frequency and with a longer latent period. Of 83 backcross mice to NFS/N, 22 developed hemopoietic tumors: 8 were diffuse lymphoblastic lymphomas; 2 were myeloid leukemias arising by 12 months of age; and 12 were follicular center cell lymphomas found later in life. Of 6 endogenous ecotropic proviruses in SL/Kh, 2 were expressed in (SL/Kh x NFS) F1 backcrossed to NFS. One, encoded by a 27-kilobase EcoRI fragment, was closely linked to Gpi-1a on chromosome 7 and its expression seemed to be a prerequisite for the occurrence of all types of hemopoietic tumors. Microsatellite analysis of the backcross generation revealed multiple host genetic factors determining susceptibility to tumors. An allele derived from SL/Kh, mapped in the major histocompatibility locus on chromosome 17, was essential for development of early onset tumors. This locus was designated as Esl-1 (early lymphoma of SL-1). On the other hand, follicular center cell lymphomas developed mostly in the backcross mice homozygous for the NFS/N derived allele at the D4MIT17-linked locus, designated as foc-1 (follicular center cell lymphoma-1), on chromosome 4.