Biomedical subjects

M Rubenstein

Publications and source records attributed to M Rubenstein.

At least 37 records · Page 2Linked to original sources

PubMed1995

Orthotopic placement of the Dunning R3327 AT-3 prostate tumor in the Copenhagen X Fischer rat.

Orthotopic placement of in vitro propagated Dunning R3327 AT-3 tumor cells resulted in a greater percentage of tumor takes and a two-fold shift in the exponential growth curve compared to flank implantation. The orthotopic tumor appeared to disseminate preferentially to regional lymph nodes, rather than to the lungs which is characteristic of flank tumors. The results suggest an important role of stromal-epithelial interactions in the growth of this tumor.

Adenocarcinoma, Papillary↗

PubMed1993

Renal cell carcinoma: the size variable.

Three hundred and thirty-seven renal cell carcinomas treated at University of Illinois Affiliated Hospitals were reviewed. There was an inverse correlation between tumor size and survival.

Carcinoma, Renal Cell↗

PubMed1993

A genetic analysis of the Werner syndrome region on human chromosome 8p.

Werner syndrome (WRN) is an inherited disorder that produces symptoms of premature aging. This disease is caused by a recessive mutation that has previously been mapped to chromosome 8p. We have now used genetic linkage analysis to map the WRN gene relative to chromosome 8 reference loci, to screen candidate genes, and to identify a novel dinucleotide repeat polymorphic marker closely linked to WRN. The WRN locus was mapped relative to the marker loci, PLAT, ANK1, D8S135, and D8S87 of the comprehensive chromosome 8 linkage map. The heregulin (HRG) and the fibroblast growth factor receptor 1 genes (FGFR1) have been mapped to chromosome 8p and are involved in cellular growth. Recombination events were detected between WRN and the HRG and FGFR1 genes, excluding them as candidates for the WRN gene. A polymorphic marker generated in this study, WT251, is linked to WRN at a recombination fraction of 0.006, with a lod score of 16.5.

Base Sequence↗

PubMed1993

Differential effect of xanthopterin and biopterin on cell growth.

1. Xanthopterin inhibited proliferation of primary renal proximal tubule cells (RPTC) and LLC-PK1 cells while in a growth phase but when incubated at confluence the cells were relatively insensitive. 2. The growth of malignant human prostate PC-3 cells was also inhibited by xanthopterin in a concentration and time dependent manner. 3. Dunning R3327 AT-3 rat prostate tumor cells which were exposed to xanthopterin in vitro before their in vivo inoculation resulted in smaller tumours while in vivo administration of xanthopterin following implantation also resulted in smaller tumors. 4. Xanthopterin exerts differential effects on cell growth dependent upon the cell origin and their state of proliferation.

Animals↗

PubMed1993

Immunopriming of tumor infiltrating lymphocytes with neoadjuvant cyclophosphamide.

Tumor infiltrating lymphocytes (TIL) are increasingly employed in immunotherapy protocols. When modified and expanded they can be utilized in new therapeutic protocols. TIL augmentation can be in vitro and in vivo. The purpose of this article is to review the various methods of TIL augmentation and report our experience with a neoadjuvant technique of cyclophosphamide immunopriming of TILs.

Adjuvants, Immunologic↗

PubMed1992

Genetic linkage of Werner's syndrome to five markers on chromosome 8.

Werner's syndrome (WS) is a rare autosomal recessive disease in which the affected individuals display symptoms of premature ageing. The substantial phenotypic overlap between WS and normal ageing indicates that these two conditions may have pathogenetic mechanisms in common. The WS mutation has pleiotropic effects, and patients and their cells show many differences compared with normals. Despite extensive study of the clinical and biochemical features of this disorder, the primary genetic defect remains unknown. We have undertaken a genetic linkage study in an effort to identify the locus of the primary defect. Here we report close genetic linkage of the WS mutation to a group of markers on chromosome 8.

Chromosome Mapping↗

PubMed1992

Microsurgical approach to the abdominal thoracic duct in the rat: considerations in the collection of lymphocytes.

In experiments involving the collection of thoracic duct lymphocytes the anatomy of the abdominal thoracic duct in the rat has been further defined. In general, the abdominal thoracic duct lies posterior and to the left of the aorta between the renal arteries and the diaphragm. There are variations in the microsurgical approach to the classically described location of this organ that should be noted by investigators attempting to identify and dissect this structure.

Animal Welfare↗

PubMed1992

The effect of BCG on thoracic duct lymphocytes.

Adoptive immunotherapy is becoming increasingly more important in the management of advanced malignancies. This report describes the results of immunomodulation therapy with BCG in the Dunning tumor. In addition it describes new techniques in the harvesting of lymphocytes. Thoracic duct lymphocytes from 34 rats were evaluated for the effect of the presence of the Dunning R-3327 AT-3 tumor as well as for the response to bacillus Calmette Guerin (BCG). Both tumor and BCG resulted in significant changes in the helper/suppressor T cell ratios.

Animals↗

PubMed1992

Coordinate loss of growth regulatory factors following castration of rats carrying the Dunning R3327 G prostatic tumor.

Hormonal manipulation of prostate cancer is an effective therapy for metastatic disease. Unfortunately, following an initial response tumors reestablish themselves as hormone independent variants and progress. This study was designed to assess the interrelationship of cytokeratin P (Cyto P), vimentin, epidermal growth factor receptor (rEGF) and tissue testosterone following androgen deprivation therapy. Animals bearing the hormone dependent Dunning R3327 G subline prostatic adenocarcinoma were surgically castrated and progressing tumors from both hormone intact and castrated groups were quantitatively assayed for immunohistologic reactivity against the described markers. The results demonstrate a significant (p < 0.05) decrease in cytokeratin (Cyto P), rEGF and testosterone levels following castration. When the expression of both rEGF and Cyto P are related to the tissue testosterone content, it is observed that the ratio between rEGF and testosterone remains essentially unchanged (0.65 +/- 0.21 to 0.65 +/- 0.41), suggesting that in the Dunning R3327 G subline, rEGF expression is coordinately under androgen control. At least some cytokeratin expression also appears to be particularly sensitive to androgen levels, since the ratio between Cyto P and testosterone decreased from 0.92 +/- 0.39 to 0.35 +/- 0.41 following castration. In contrast, following castration, the expression of vimentin was unaffected.

Adenocarcinoma↗

PubMed1991

Bone scan as a stratification variable in advanced prostate cancer.

The serial technetium 99 (99Tc) bone scans of 76 patients with Stage D-2 prostate cancers were reviewed. Sites of metastases in skeletal areas in decreasing order were vertebrae, ribs, pelvis, long bones, and skull. Patients with one or two involved skeletal areas had a significantly longer progression-free interval and survival time than patients with three or more bony areas of uptake. Bone scans might be used as a stratification variable in future prospective clinical trials of Stage D-2 prostate cancer.

Aged↗

PubMed1991

Characterization of cellular infiltrates in the rat urinary bladder following BCG and thiotepa intravesical therapy.

We examined rat urinary bladders following intravesical administration of BCG and thiotepa. BCG administration resulted in a relatively greater increase in the mucosal infiltration of mononuclear cells relative to polymorphonuclear cells (P less than 0.01) compared to the thiotepa treated bladders. This finding suggests that the mode of action of the therapeutic effects of these agents may be different. These results may also suggest that the mechanism of action of BCG might be immunologic in nature.

Administration, Intravesical↗

PubMed1991

Cytoreductive surgery impedes metastasis and enhances the immune response: a preliminary report.

In an effort to determine the effect of cytoreductive surgery on the metastatic process, MAT-LyLu flank tumors were excised from Copenhagen x Fischer rats and the effects of this surgery on metastatic lung lesions were observed. Cytoreduction resulted in a decrease in lung lesions (P less than 0.05). Adjuvant cyclophosphamide (CTX) further enhanced this beneficial effect. A concurrent increase in the helper/suppressor ratios suggested that this beneficial response might be mediated by the host's immune response.

Animals↗

PubMed1991

GM-CSF restoration of a differentiated (growth factor-regulated) phenotype in an anaplastic tumor.

GM-CSF (granulocyte-macrophage-derived colony-stimulating factor) is a differentiation agent that stimulates bone marrow activity in patients receiving chemotherapy. GM-CSF (1 microgram/ml daily for 10 days), administered intralesionally, was evaluated to determine whether it would restore a more differentiated phenotype to an anaplastic, rapidly growing, hormone-independent variant (R3327 MAT-LyLu) of the Dunning prostatic adenocarcinoma. Immunohistology was used to quantitate the expression of epithelial growth factor receptors (rEGF) and the tissue testosterone content. GM-CSF therapy significantly (P less than 0.05) restored rEGF expression and tissue testosterone to levels associated with better differentiated, slower growing, androgen-dependent Dunning variants (R3327 H and G). GM-CSF may have a role in treatment of prostatic cancers by promoting androgen and epithelial growth factor regulation.

Adenocarcinoma↗

PubMed1991

Tumor infiltrating lymphocytes: the effect of bacillus Calmette Guerin on helper/suppressor-T cell ratios of treated and untreated tumors.

Copenhagen X Fischer rats bearing single and bilateral Dunning R3327 AT-3 tumors were either treated or not treated at a single site with bacillus Calmette Guerin (BCG). One week later tumors were removed, tumor infiltrating lymphocytes (TIL's) isolated, and then characterized for total-T, helper-T and suppressor-T cell subsets utilizing monoclonal antibodies. The purpose was to determine the effect of BCG on TIL's in treated as well as untreated tumors. In summary: 1) BCG treatment significantly alters TIL distributions at both injected and noninjected sites; 2) a noninjected contralateral tumor compromises the effectiveness of BCG therapy at the suppressor T cell level; 3) contralateral tumors, whether inoculated or not, have similar TIL distributions.

Animals↗

PubMed1990

An immunohistologic characterization of human prostatic atypical hyperplasia.

In an effort to better distinguish the morphologic relationship of atypical hyperplasia of the prostate to benign prostatic hypertrophy and prostatic cancer, 43 prostate specimens were analyzed with ten immunohistologic markers. Two cytokeratin antibodies appeared useful (Cyto M and Cyto P, with the latter slightly more discriminatory). In summary, it appears that atypical hyperplasia is immunohistopathologically related to both benign prostatic hypertrophy and prostatic cancer, having characteristics of both.

Aged↗

PubMed1990

Efficacy of immunopriming prior to isolation of tumor infiltrating lymphocytes for use in adoptive immunotherapy.

Adoptive immunotherapy is dependent upon the leukocytic subsets isolated as tumor infiltrating lymphocytes (TIL) prior to in vitro expansion with interleukin-2. To favorably influence T-cell subset representation in TIL the efficacy of bacillus Calmette Guerin (BCG) and cyclophosphamide (CTX) priming was evaluated in rats bearing Dunning R3327-AT prostatic tumors. When assessed by immunohistochemistry, both agents significantly (p less than 0.001) increased helper-T representation and decreased that by suppressor-T cells. As a result helper/suppressor (H/S) T cell ratios of TIL from untreated tumors (0.73 +/- 0.11) were significantly (p less than 0.001) elevated by both BCG (1.93 +/- 0.39) and CTX (1.40 +/- 0.25). Immunopriming might enhance adoptive immunotherapy by increasing the H/S ratio of TIL prior to their culture.

Animals↗

PubMed1990

Effect of early and delayed difluoromethylornithine pretreatment upon cyclophosphamide chemotherapy.

The Dunning R3327 MAT-LyLu prostatic adenocarcinoma was utilized to study the effectiveness of an early versus delayed difluoromethylornithine (DFMO)-induced polyamine-depleted environment on cyclophosphamide (CTX) chemotherapy. DFMO (2%) was administered either at the time of tumor inoculation (early) or 36 h after tumor implantation (delayed). CTX (50 mg/kg) was administered to both DFMO groups in two doses; the first 36 h after initiation of DFMO therapy, and the second 1 week later. Each protocol (early and delayed) for combined DFMO/CTX chemotherapy significantly reduced tumor sizes with the earlier DFMO protocol appearing slightly more effective (p less than 0.001 and 0.02, respectively). DFMO administered alone was not significantly effective with either protocol.

Adenocarcinoma↗

PubMed1989

Evaluation of cytokeratin markers to differentiate between benign and malignant prostatic tissue.

Cytokeratins are intermediate filaments found within basal and secretory epithelial cells. Antisera raised against cytokeratins are available but frequently differ in specificity. Many are incompletely characterized for their reactivity against epithelial components. Cytokeratin (Cyto) P is a polyclonal antisera specific for 56 and 64 kd cytokeratins. Cyto M is a pool of monoclonals reacting against 40, 46, 50, 52, 58, and 65-67 kd cytokeratins. Initially, utilizing immunohistologic techniques, we evaluated these two antisera for their ability to distinguish between prostatic tissues of benign (benign prostatic hypertrophy [BPH]) or malignant (carcinoma of the prostate [CAP]) origin in the 34 cases evaluated. Specimens were analyzed for both Cyto P and Cyto M reactivity, as well as for the degree of reactivity. Lastly, in an effort to determine the morphologic relationship of atypical hyperplasia (AH) with either BPH or CAP, nine additional prostate specimens were analyzed. Cyto P was reactive in 8 of 8 (100%) BPH specimens and in 2 of 26 (8%) CAP specimens. Mean Cyto P degree of reactivity in the positive specimens was greater in BPH than in CAP (2.6 vs. 1.0). Cyto M reactivity was present in 8 of 8 (100%) BPH specimens and in 23 of 25 (92%) CAP specimens. Mean Cyto M degree of reactivity in the positive specimens was greater in CAP than in BPH (3.6 vs. 2.8). Cyto P was reactive in 3 of 9 (33%) AH specimens, with a mean degree of reactivity of 2.7. Cyto M was reactive in 9 of 9 (100%) AH specimens, with a mean degree of reactivity of 3.9. Cyto P reacted with only the basal cells, whereas Cyto M reacted with basal as well as secretory cells. These differences appeared to be the result of the differential reactivity of basal cells, which are present in BPH but absent in CAP. In summary, Cyto P and Cyto M are potentially useful markers in differentiating BPH from CAP, and it appears that AH is immunohistopathologically related to both.

Aged↗