To evaluate (64)Cu-TP3805 as a novel biomolecule, to PET image prostate cancer (PC), at the onset of which VPAC1, the superfamily of G-protein coupled receptors, is expressed in high density on PC cells, but not on normal cells. 25... more
To evaluate (64)Cu-TP3805 as a novel biomolecule, to PET image prostate cancer (PC), at the onset of which VPAC1, the superfamily of G-protein coupled receptors, is expressed in high density on PC cells, but not on normal cells. 25 patients undergoing radical prostatectomy were PET/CT imaged preoperatively with (64)Cu-TP3805. Standardized uptake values (SUVmax) were determined, malignant lesions (SUV > 1.0) counted, and compared with histologic findings. Whole mount pathology slides from 6 VPAC1 PET imaged patients, 3 BPH patients, one malignant and one benign lymph node underwent digital autoradiography (DAR) after (64)Cu-TP3805 incubation and compared to H&E stained slides. In 25 patient PET imaging, 212 prostate gland lesions had SUVmax > 1.0 vs.127 lesions identified by histology of biopsy tissues. The status of the additional 85 PET identified prostate lesions remains to be determined. In 68 histological slides from 6 PET imaged patients, DAR identified 105/107 PC foci, 1...
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Active Stat5a/b predicts early recurrence and disease-specific death in prostate cancer (PC), which both typically are caused by development of metastatic disease. Herein, we demonstrate that Stat5a/b induces epithelial-to-mesenchymal... more
Active Stat5a/b predicts early recurrence and disease-specific death in prostate cancer (PC), which both typically are caused by development of metastatic disease. Herein, we demonstrate that Stat5a/b induces epithelial-to-mesenchymal transition (EMT) of PC cells, as shown by Stat5a/b regulation of EMT marker expression (Twist1, E-cadherin, N-cadherin, vimentin, and fibronectin) in PC cell lines, xenograft tumors in vivo, and patient-derived PCs ex vivo using organ explant cultures. Jak2-Stat5a/b signaling induced functional end points of EMT as well, indicated by disruption of epithelial cell monolayers and increased migration and adhesion of PC cells to fibronectin. Knockdown of Twist1 suppressed Jak2-Stat5a/b-induced EMT properties of PC cells, which were rescued by re-introduction of Twist1, indicating that Twist1 mediates Stat5a/b-induced EMT in PC cells. While promoting EMT, Jak2-Stat5a/b signaling induced stem-like properties in PC cells, such as sphere formation and expression of cancer stem cell markers, including BMI1. Mechanistically, both Twist1 and BMI1 were critical for Stat5a/b induction of stem-like features, because genetic knockdown of Twist1 suppressed Stat5a/b-induced BMI1 expression and sphere formation in stem cell culture conditions, which were rescued by re-introduction of BMI1. By using human prolactin knock-in mice, we demonstrate that prolactin-Stat5a/b signaling promoted metastases formation of PC cells in vivo. In conclusion, our data support the concept that Jak2-Stat5a/b signaling promotes metastatic progression of PC by inducing EMT and stem cell properties in PC cells.
Pancreatic ductal adenocarcinoma (PDA) harbors an exceedingly poor prognosis, and is generally considered a therapy-recalcitrant disease due to poor response to conventional chemotherapy coupled with non-actionable genetic drivers (e.g.... more
Pancreatic ductal adenocarcinoma (PDA) harbors an exceedingly poor prognosis, and is generally considered a therapy-recalcitrant disease due to poor response to conventional chemotherapy coupled with non-actionable genetic drivers (e.g. KRAS mutations). However, PDA frequently loses p16ink4a, thereby leading to deregulation of CDK4/6. Surprisingly, in established cell models and xenografts, CDK4/6 inhibition has a modest effect on proliferation and resistance develops rapidly. To determine if such weak response was an intrinsic feature of PDA, we developed primary tumor explants that maintain the tumor environment and recapitulate feuture of primary PDA. The CDK4/6 inhibitor PD-0332991 was highly efficient at suppressing proliferation in 14 of the 15 explants. In the single resistant explant, we identified the rare loss of the RB tumor suppressor as the basis for resistance. Patient-derived xenografts (PDXs) were developed in parallel, and unlike the xenografts emerging from establi...
Uveal melanoma patients with metastatic disease usually die within one year, emphasizing an urgent need to develop new treatment strategies for this cancer. MEK inhibitors improve survival in cutaneous melanoma patients but show only... more
Uveal melanoma patients with metastatic disease usually die within one year, emphasizing an urgent need to develop new treatment strategies for this cancer. MEK inhibitors improve survival in cutaneous melanoma patients but show only modest efficacy in metastatic uveal melanoma patients. In this study, we screened for growth factors that elicited resistance in newly characterized metastatic uveal melanoma cell lines to clinical-grade MEK inhibitors, trametinib and selumetinib. We show that neuregulin 1 (NRG1) and hepatocyte growth factor (HGF) provide resistance to MEK inhibition. Mechanistically, trametinib enhances the responsiveness to NRG1 and sustained HGF-mediated activation of AKT. Individually targeting ERBB3 and cMET, the receptors for NRG1 and HGF, respectively, overcome resistance to trametinib provided by these growth factors and by conditioned medium from fibroblasts that produce NRG1 and HGF. Inhibition of AKT also effectively reverses the protective effect of NRG1 and...
Research Interests: Cancer, Humans, Mice, Melanoma, Animals, and 3 moreBenzimidazoles, Neuregulin 1, and Hepatocyte Growth Factor
Bypassing tyrosine kinases responsible for Stat5a/b phosphorylation would be advantageous for therapy development for Stat5a/b-regulated cancers. Here, we sought to identify small-molecule inhibitors of Stat5a/b for lead optimization and... more
Bypassing tyrosine kinases responsible for Stat5a/b phosphorylation would be advantageous for therapy development for Stat5a/b-regulated cancers. Here, we sought to identify small-molecule inhibitors of Stat5a/b for lead optimization and therapy development for prostate cancer (PC) and Bcr-Abl-driven leukemias. In silico screening of chemical structure databases combined with medicinal chemistry was used for identification of a panel of small-molecule inhibitors to block SH2-domain-mediated docking of Stat5a/b to the receptor-kinase complex and subsequent phosphorylation and dimerization. We tested the efficacy of the lead-compound, IST5-002, in experimental models and patient samples of two known Stat5a/b-driven cancers, prostate cancer (PC) and chronic myeloid leukemia (CML). The lead compound Inhibitor of Stat5-002 (IST5-002) prevented both Jak2 and Bcr-Abl-mediated phosphorylation and dimerization of Stat5a/b, and selectively inhibited transcriptional activity of Stat5a (IC50 1....
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To determine the possible role of Ki-67 antigen expression by visual and computed quantitation in diagnosing ampullary lesions. Twenty-two cases of ampullary lesions treated at Thomas Jefferson University Hospital between 1989 and 1994... more
To determine the possible role of Ki-67 antigen expression by visual and computed quantitation in diagnosing ampullary lesions. Twenty-two cases of ampullary lesions treated at Thomas Jefferson University Hospital between 1989 and 1994 were analyzed. Four cases of adenoma, 4 of epithelial dysplasia in adenoma, 7 of well-differentiated adenocarcinoma and 7 of high grade adenocarcinoma were included. For each case three consecutive sections were obtained from the paraffin-embedded blocks. The first slide was stained with hematoxylin & eosin for visual diagnosis; the other two were immunoprocessed to evaluate the expression of Ki-67 antigen. Visual quantitation of Ki-67 was evaluated by light microscopy, and computed quantitation was performed utilizing the SAMBA 4000 cell image analysis system. Immunohistochemical analysis of the ampullary lesions showed a positive correlation of Ki-67 expression, both by visual and computed quantitation, with biologic grade. The cell proliferation se...
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Experimental studies in the therapy of intravesically growing bladder tumors in mice have been hampered by an inability to monitor tumor growth before and during treatment. To establish a repeatable, noninvasive method to monitor the... more
Experimental studies in the therapy of intravesically growing bladder tumors in mice have been hampered by an inability to monitor tumor growth before and during treatment. To establish a repeatable, noninvasive method to monitor the intravesical growth of bladder tumors, MB49 murine bladder tumor cells were instilled into the bladders of syngeneic C57BL/6 mice. Following 3 weeks of growth, the bladders of tumor-bearing and control mice were imaged using a 20 mHz, 6.2 F catheter-based ultrasound transducer inserted rectally. Bladders of tumor implanted and control mice were identified by high resolution endoluminal ultrasound after distension with 0.15 ml. of normal saline. When compared with the results of histologic analysis, transrectal ultrasound (TRUS) accurately identified tumor presence, size, and location.
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Cryopreserved cell suspensions of freshly excised melanoma metastases from nine patients were injected s.c. into C.B-17 severe combined immunodeficiency (SCID) mice. All 9 tumors grew as s.c. masses and six of nine were successfully... more
Cryopreserved cell suspensions of freshly excised melanoma metastases from nine patients were injected s.c. into C.B-17 severe combined immunodeficiency (SCID) mice. All 9 tumors grew as s.c. masses and six of nine were successfully transplanted into other SCID mice. Transplant inocula as low as 5 x 10(5) cells resulted in 100% tumor incidence. Moreover, seven of nine tumors metastasized, five from the original s.c. implants and two from transplanted s.c. tumors. Metastases were detected mainly in the lungs but also were found in abdominal viscera (liver, spleen, and pancreas) and thoracic lymph nodes. Flow cytometric analysis showed that expression of a panel of melanoma antigens, melanoma-associated proteoglycan, ganglioside GD3, and ganglioside GD2, was maintained with SCID passage. The original tumor inocula contained a variable percentage of tumor-associated lymphocytes (1-76%). Flow cytometry analysis indicated that these were mainly CD3+ T-cells. However, there was no correla...
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Involvement of the 3p14.2 region of chromosome 3 in kidney cancers was suggested 20 years ago, when a reciprocal constitutional translocation, t(3;8)(p14.2;q24), was shown to segregate with bilateral clear cell renal carcinoma in 3... more
Involvement of the 3p14.2 region of chromosome 3 in kidney cancers was suggested 20 years ago, when a reciprocal constitutional translocation, t(3;8)(p14.2;q24), was shown to segregate with bilateral clear cell renal carcinoma in 3 generations of 1 family. The FHITgene that is interrupted at 3p14.2 by the t(3;8) translocation has been isolated, characterized, and shown to be frequently altered, mainly by internal deletion, in carcinomas or cancer-derived cell lines of the lung, stomach, pancreas, esophagus, cervix, and colon. Although up to 90% of sporadic clear cell renal carcinomas, representing 70% of adult renal carcinomas, exhibit loss of FHIT alleles, FHIT gene alterations have been documented for only a few renal cell carcinoma-derived cell lines. Nevertheless, more than 50% of clear cell carcinomas were recently shown to express little or no Fhit protein, unlike the normal kidney tubule epithelium, which is uniformly strongly positive for Fhit expression. We have extended ou...
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Evidence for alteration of the FHIT gene in a significant fraction of breast carcinomas has been reported, in apparent concordance with loss of heterozygosity (LOH) at chromosome region 3p14.2 in breast cancer and benign proliferative... more
Evidence for alteration of the FHIT gene in a significant fraction of breast carcinomas has been reported, in apparent concordance with loss of heterozygosity (LOH) at chromosome region 3p14.2 in breast cancer and benign proliferative breast disease. A significantly higher frequency of LOH at the FHIT locus was reported for BRCA2-/- tumors, possibly due to misrepaired double-strand breaks at this common fragile region. To determine whether such genomic alterations lead to Fhit inactivation, we have assessed the level of Fhit expression by immunohistochemical detection in sporadic tumors and cancers occurring in BRCA2 999del5 carriers. To determine whether Fhit inactivation may have prognostic significance, we have also assessed expression of breast cancer markers and clinical features in sporadic tumors relative to Fhit expression. Of 40 consecutive sporadic breast carcinomas studied for tumor markers, 50% showed reduced Fhit expression. In these sporadic cancers, loss of Fhit expre...
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Interleukin 10 (IL-10) has the physiological role of down-regulating cell-mediated immunity. We have recently reported that mRNA for IL-10 was present in most metastatic melanoma tissues. The purpose of this investigation was to determine... more
Interleukin 10 (IL-10) has the physiological role of down-regulating cell-mediated immunity. We have recently reported that mRNA for IL-10 was present in most metastatic melanoma tissues. The purpose of this investigation was to determine whether melanoma metastases produce IL-10 protein. Single-cell suspensions were prepared by enzymatic dissociation of 28 lymph node metastases and 7 s.c. metastases and cryopreserved. Of these 35 samples, 30 produced IL-10 after a 24-h incubation (median, 125.1 pg/ml). IL-10 production was slightly diminished after 25 Gy irradiation but almost completely abrogated after modification with the hapten dinitrophenyl. After 7 or 14 days in tissue culture, melanoma cells continued to produce IL-10 but only at about 10% of the levels of freshly dissociated tissues. Moreover, of eight melanoma cell lines established from these cultures, only one produced IL-10 protein. To determine whether IL-10 was produced by melanoma cells or tumor-associated leukocytes...
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The FHIT gene, encoded by 10 exons in a 1.1-kb transcript, encompasses approximately 1 Mb of genomic DNA, which includes the hereditary RCC t(3;8) translocation break at 3p14.2, the FRA3B common fragile region, and homozygous deletions in... more
The FHIT gene, encoded by 10 exons in a 1.1-kb transcript, encompasses approximately 1 Mb of genomic DNA, which includes the hereditary RCC t(3;8) translocation break at 3p14.2, the FRA3B common fragile region, and homozygous deletions in various cancer-derived cell lines. Because some of these genetic landmarks (e.g., the t(3;8) break between untranslated FHIT exons 3 and 4, a major fragile region that includes a viral integration site between exons 4 and 5, and cancer cell homozygous deletions in intron 5) do not necessarily affect coding exons and yet apparently affect expression of the gene product, we examined the FHIT locus and its expression in detail in more than 10 tumor-derived cell lines to clarify mechanisms underlying aberrant expression. We observed some cell lines with apparently continuous large homozygous deletions, which included one or more coding exons; cell lines with discontinuous deletions, some of which included or excluded coding exons; and cell lines that e...
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Embryonal carcinoma cells provide a convenient and manipulable model for early embryogenesis. Like their counterparts in the inner cell mass, they are refractory to infection by several viruses. In their undifferentiated state, EC cells... more
Embryonal carcinoma cells provide a convenient and manipulable model for early embryogenesis. Like their counterparts in the inner cell mass, they are refractory to infection by several viruses. In their undifferentiated state, EC cells are resistant to calcium-phosphate DNA transfection. This resistance is compounded by the inefficient and/or actively inhibited expression of transfected genes driven by certain viral promoters. Conversely, the differentiated derivatives do not share this resistance and readily express virally promoted genes. We have developed a protocol for liposome-mediated gene transfer in EC cells and compared its efficiency in wild-type and retinoid-resistant variants. Dose response experiments with the EC cell line PCC4.aza1R showed a linear progression of colony formation when transfected with the vector pSV3neo and selected in medium containing the antibiotic G418. DNA concentrations of 10 micrograms per plate resulted in over 600 colonies per 10(6) cells. Th...
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An in vivo model for human melanoma was established with the growth of CR3 and DE5 human melanoma tumor cells following i.v. injection into C.B.-17 severe combined immunodeficient mice depleted of murine natural killer (NK) cells. The... more
An in vivo model for human melanoma was established with the growth of CR3 and DE5 human melanoma tumor cells following i.v. injection into C.B.-17 severe combined immunodeficient mice depleted of murine natural killer (NK) cells. The ability of human NK cells to mediate antitumor activity in vivo was investigated by evaluating the number of lung nodules and survival of mice given injections of human NK cells i.v. early after injection of CR3 tumor cells. Under these conditions, human NK cells effectively reduced lung nodule counts and prolonged survival when coinjected with interleukin 2 (IL-2). Multiple injections of IL-2 given during the first 16 h post-NK injection did not further enhance the tumor reduction. Significantly increased antitumor activity against CR3 tumor cells in vivo was observed in mice receiving NK cells coinjected with IL-2 and interleukin 12 (IL-12) in comparison to NK cells and IL-2 only. However, coinjection of IL-12 with human NK cells alone did not reduce...
Research Interests: Cancer, Cell Division, Humans, Natural Killer cells, Mice, and 5 moreFemale, Melanoma, Animals, Male, and Interleukin
Intratumoral gene transfer may be a significant tool in active immunotherapy. The ability to insert functional genes into a tumor in vitro and in vivo using recombinant vaccinia vectors was examined in the murine bladder tumor model.... more
Intratumoral gene transfer may be a significant tool in active immunotherapy. The ability to insert functional genes into a tumor in vitro and in vivo using recombinant vaccinia vectors was examined in the murine bladder tumor model. Vaccinia recombinants expressing the influenza hemagglutinin or nucleoprotein antigens infected/transfected murine (MB-49 and MBT-2) and human (T24) bladder tumor cell lines in vitro. Systemic vaccinia immunity was induced with as few as 10 plaque-forming units of recombinant vaccinia instilled intravesically, and the encoded protein was expressed in vivo in tumor and urothelium. However, preimmunity to vaccinia did not inhibit intravesical tumor transfection. Thus, recombinant vaccinia virus is effective in introducing foreign antigens locally into tumor in vivo, supporting its use in clinical immunotherapy.
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Nearly all clear cell renal cell carcinomas (RCCs) exhibit loss of alleles on the short arm of chromosome 3. Loss and mutation at the von Hippel-Lindau (VHL) gene at 3p25 probably occurs in most RCCs and, since the VHL gene was recently... more
Nearly all clear cell renal cell carcinomas (RCCs) exhibit loss of alleles on the short arm of chromosome 3. Loss and mutation at the von Hippel-Lindau (VHL) gene at 3p25 probably occurs in most RCCs and, since the VHL gene was recently cloned, data on VHL involvement in RCCs is accumulating. However, the region 3p14-p12, a region that contains the familial RCC-associated t(3;8)(p14.2;q24) chromosome translocation and the small cell lung carcinoma-associated homozygous deletion at 3p13-12, has also been reported to exhibit allele loss in a large fraction of RCCs. In order to focus future studies on potential suppressor genes in the 3p14-p12 region, we have studied allele loss in 30 RCCs with 9 polymorphic simple sequence repeat markers spanning 3p21.1-p12. Partial losses in the 3p21-p12 region were observed, allowing determination of common regions of loss of heterozygosity overlap in 15 RCCs. Results suggested that most RCCs exhibit loss in a region which brackets the t(3;8) famili...
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The 1991 Bethesda System states that atypical squamous or glandular cells of undetermined significance should be further classified as reactive or premalignant/malignant. The validity of this qualification for identification of patients... more
The 1991 Bethesda System states that atypical squamous or glandular cells of undetermined significance should be further classified as reactive or premalignant/malignant. The validity of this qualification for identification of patients with cervical intraepithelial neoplasia (CIN) was tested. One hundred twenty-four cytologic smears with squamous atypia were reviewed retrospectively by two cytopathologists blind to the colposcopy results. The smears were classified as favoring either reactive or premalignant/malignant processes. Subjective criteria used in the classification were based on the pathologists' experience. All patients underwent colposcopy and selected biopsy under the direction of a gynecologic oncologist. Of the 124 atypical smears, 69 were classified as favoring reactive processes and 55 as favoring premalignant/malignant processes by cytopathologist 1. Cytopathologist 2 classified 68 as reactive and 56 as premalignant/malignant. Colposcopy and selected biopsy re...
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Metastatic involvement of pelvic lymph nodes in carcinoma of the prostate alters the prognosis and treatment of this disease. Our goal was to determine if additional techniques, such as immunohistochemical staining, could detect occult... more
Metastatic involvement of pelvic lymph nodes in carcinoma of the prostate alters the prognosis and treatment of this disease. Our goal was to determine if additional techniques, such as immunohistochemical staining, could detect occult microscopic metastatic nodal disease not seen with routine hematoxylin and eosin staining. We examined paraffin embedded lymph nodes from 43 patients with clinical stage A or B carcinoma of the prostate who were candidates for radical prostatectomy and who underwent modified pelvic lymph node dissection with frozen section hematoxylin and eosin staining. Immunohistochemical staining for prostate specific antigen and prostate specific acid phosphatase was performed on the lymph nodes. Monoclonal antibodies to cytokeratins were used to confirm the epithelial origin of the prostate cells. An average of 9 lymph nodes and 42 histological sections per patient were stained. Based on routine hematoxylin and eosin staining the pathological staging was stage A ...
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Previously, we had observed that more than 80% of clear cell renal carcinomas (RCCs) exhibited loss of heterozygosity (LOH) between the microsatellite markers D3S1285 (in 3p14.1) and D3S1295 (in 3p21.1), a region which includes the... more
Previously, we had observed that more than 80% of clear cell renal carcinomas (RCCs) exhibited loss of heterozygosity (LOH) between the microsatellite markers D3S1285 (in 3p14.1) and D3S1295 (in 3p21.1), a region which includes the protein tyrosine phosphatase gamma locus (PTPRG locus, PTP gamma gene) and the 3p14.2 break of the familial RCC-associated translocation, t(3;8)(p14.2;q24), which has been hypothesized to affect expression of an RCC suppressor gene or oncogene. Using seven microsatellite markers and four markers derived from a PTPRG YAC contig, we have further delineated the 3p14.2 region of LOH in RCCs. Eighty-nine % of clear cell RCCs (31 of 35) showed a common region of loss between the D3S1481 and D3S1312 loci which flank the 3p14.2 t(3;8) translocation breakpoint and the PTP gamma gene. The PTP gamma gene occupies approximately 780 kilobase pairs between markers D3S1480 and D3S1312, with its currently defined 5' end greater than 200 kilobase pairs centromeric to ...
Research Interests: Cancer, Humans, Female, Male, Aged, and 3 moreMiddle Aged, Base Sequence, and Protein Tyrosine Phosphatases
It has been proposed that cellular retinoic acid binding protein is essential for retinoid-induced differentiation of embryonal carcinoma line PCC4.aza1R. To assess the generality of this proposal, we have tested for the presence of... more
It has been proposed that cellular retinoic acid binding protein is essential for retinoid-induced differentiation of embryonal carcinoma line PCC4.aza1R. To assess the generality of this proposal, we have tested for the presence of cellular retinoic acid binding protein activities in several other embryonal carcinoma lines. Cytosolic extracts from all cells were found to possess binding proteins for retinoic acid and also for retinol, although levels varied widely among the different lines. There was no clear quantitative relationship between binding protein activities and the propensity of the cells for differentiation in tumor form or under various in vitro conditions. Our results suggest that other factors might modulate the response of embryonal carcinoma cells to retinoids and/or that alternate pathways for differentiation which do not involve retinoids and retinoid binding proteins exist in these cells. When embryonal carcinoma cells are stimulated to differentiate, the deriv...
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The transformation of a normal cell through dysplasia to the malignant state usually is associated with changes at the molecular level within the nucleus, cytoplasm and cell surface. These changes can be monitored by the loss of normal... more
The transformation of a normal cell through dysplasia to the malignant state usually is associated with changes at the molecular level within the nucleus, cytoplasm and cell surface. These changes can be monitored by the loss of normal cell surface antigens, such as the blood group antigen ABO(H) and major histocompatibility complex antigens, which in the human correlate with the histocompatibility locus antigens. A group of patients with bladder biopsy and diagnosis ranging from normal through severe dysplasia to papillary transitional cell carcinoma, invasive transitional cell carcinoma and carcinoma in situ were evaluated for the presence or absence of beta-2-microglobulin. This 11,000 molecular weight protein was used as an indirect marker for the major histocompatibility complex antigens on the cell surface. With immunoperoxidase as a marker, the presence of beta-2-microglobulin was seen in all patients with normal epithelium as well as benign disease. However, with progression...
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We have examined the effects of dietary retinoids upon the growth and differentiation of seven embryonal carcinoma lines in mice. The control diet contained 4000 IU/mg retinyl palmitate; the other diets contained 2 x 10(5) IU/mg retinyl... more
We have examined the effects of dietary retinoids upon the growth and differentiation of seven embryonal carcinoma lines in mice. The control diet contained 4000 IU/mg retinyl palmitate; the other diets contained 2 x 10(5) IU/mg retinyl palmitate, 50 mg/kg all-trans-retinoic acid (RA), 100 mg/kg RA, and no retinoid. The RA-containing diets had little influence on tumor latency or incidence but did suppress growth of many of the tumors. Decreased tumor mass was, in most but not all instances, accompanied by an increased proportion of differentiated cells. Increased differentiation was most commonly quantitative rather than qualitative; i.e., there was a larger proportion of the same types of differentiated cells seen in tumors from the control diet group rather than an increase in the spectrum of cell types observed. Notably, tumors from two differentiation-defective embryonal carcinoma lines were refractory to both the differentiation-inducing and growth-suppressing properties of di...
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The status of the T cell receptor beta and gamma genes in natural killer (NK) cells was investigated in two patients with a marked expansion of CD2+, CD3- NK cells. Both genes were found to be in the germline state. The T alpha and... more
The status of the T cell receptor beta and gamma genes in natural killer (NK) cells was investigated in two patients with a marked expansion of CD2+, CD3- NK cells. Both genes were found to be in the germline state. The T alpha and complete T beta gene transcripts were not detected, but a 1.0-kilobase T beta gene transcript could be demonstrated at low levels in freshly isolated cells and at a much higher level in interleukin-2 (IL-2)-cultured cells. The transcript coding for the delta chain of the CD3 complex was also absent. These cells were cultured in IL-2 with or without the addition of the differentiation-inducing agents: retinoic acid, N,N-hexamethylene bisacetamide, and sodium butyrate. The cultured cells retained their NK activity except in culture with sodium butyrate at greater than or equal to 1 mmol/L. Expression of CD3 or other T cell surface markers by the NK cells was not observed in these cultures. Either CD2+, CD3- NK cells are derived from a non-T lineage, or they...
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Urothelial recurrence of renal cell carcinoma after radical surgery is exceedingly rare. We report on a 48-year-old man who underwent upper urinary tract flexible endoscopy to define a filling defect, which was found to be a perforating... more
Urothelial recurrence of renal cell carcinoma after radical surgery is exceedingly rare. We report on a 48-year-old man who underwent upper urinary tract flexible endoscopy to define a filling defect, which was found to be a perforating renal cell carcinoma. After radical nephrectomy the patient had multiple recurrences on the urinary surfaces, ureter and urethra. Urothelial lesions were treated endoscopically. He remains free of tumor 42 months after the last treatment.
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Prostate cancer (PCa) is the second leading form of cancer death in men. In a subset of PCa patients increased chemokine signaling IL-8 and IL-6 correlates with androgen therapy-resistant prostate cancer (CRPC). IL-8 and IL-6 are produced... more
Prostate cancer (PCa) is the second leading form of cancer death in men. In a subset of PCa patients increased chemokine signaling IL-8 and IL-6 correlates with androgen therapy-resistant prostate cancer (CRPC). IL-8 and IL-6 are produced by prostate epithelial cells and promote PCa cell invasion, however the mechanisms restraining prostate epithelial cell cytokine secretion are poorly understood. Herein the cell-fate determinant factor DACH1 inhibited androgen therapy-resistant prostate cancer (CRPC) tumor growth in mice. Using Dach1fl/fl/Probasin-Cre bi-transgenic mice, we show IL-8 and IL-6 secretion was altered ~1000 fold by endogenous Dach1. Endogenous Dach1 is shown to serve as a key endogenous restraint to prostate epithelial cell growth and restrains migration via CXCL signaling. DACH1 inhibited expression, transcription and secretion of the CXCL genes (IL-8, IL-6) by binding to their promoter regulatory regions in chromatin. DACH1 is thus a newly defined determinant of beni...
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The FHIT gene, which encodes a 1-kb message and a 16.8-kDa protein that hydrolyses diadenosine triphosphate (ApppA) to ADP and AMP in vitro, covers a megabase genomic region at chromosome band 3p14.2. The gene encompasses the most active... more
The FHIT gene, which encodes a 1-kb message and a 16.8-kDa protein that hydrolyses diadenosine triphosphate (ApppA) to ADP and AMP in vitro, covers a megabase genomic region at chromosome band 3p14.2. The gene encompasses the most active of the common human chromosomal fragile regions, FRA3B. Over the years, it has been suggested that fragile sites might be especially susceptible to carcinogen damage and that chromosomal regions of nonrandom alterations in cancer cells may coincide with defined fragile sites. Within the FRA3B region, the characteristic induced chromosome gaps can occur across the entire region, but 60% of the gaps are centered on a 300-kb region flanking FHIT exon 5, the first protein-coding exon. Numerous hemizygous and homozygous deletions, translocations and DNA insertions occur within FHIT in cancer cell lines, uncultured tumors, and even in preneoplastic lesions, especially in tissues such as lung that are targets of carcinogens. This supports the proposed cancer-fragile site connection and suggests that the FHIT gene, expression of which is frequently altered in cells showing FHIT locus damage, is a tumor suppressor gene whose inactivation may drive clonal expansion of preneoplastic and neoplastic cells. Replacement of Fhit expression in Fhit-negative cancer cells abrogates their tumorigenicity in nude mice. Analysis of the approximately 300-kb DNA sequence encompassing FHIT exon 5 in the FRA3B epicenter has provided clues to the mechanism of repair of the fragile site double strand breaks. The mechanism involves recombination between LINE 1 elements with deletion of the intervening sequence, often including FHIT exons. These studies have also shown that FHIT alterations generally entail independent deletion of both FHIT alleles. Future studies will focus on two objectives: study of (1) the in vivo function of the Fhit protein and (2) mechanisms of break and repair in the FRA3B fragile region.
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Hyaline globules (extracellular collections of amorphous material) are identified in 10 of 59 renal cell carcinomas (RCC) and in 2 of 9 oncocytomas. Immunohistochemical characterization of these PAS-positive structures revealed the... more
Hyaline globules (extracellular collections of amorphous material) are identified in 10 of 59 renal cell carcinomas (RCC) and in 2 of 9 oncocytomas. Immunohistochemical characterization of these PAS-positive structures revealed the presence of basement membrane material in most cases. Collagen type IV and laminin were the predominant constituents, whereas fibronectin was detected only occasionally. Electron microscopic examination of the globules showed concentric multilayered accumulations of basement membrane material. No such structures were recognized in 8 renal pelvic transitional cell carcinomas nor in 2 metanephric adenomas. RCC associated hyaline globules were always negative for alpha1-antitrypsin (AAT), alpha-fetoprotein (AFP), amyloid A, cytokeratin, vimentin, or lysozyme. These features differ from those of the hyaline globules previously described in other malignant neoplasms, notably AAT-positive hyaline globules in ovarian tumors, and AFP-positive globules in yolk sac tumors. Identification and immunohistochemical characterization of hyaline globules in metastases may be helpful in determining the origin of occult primary tumors.
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Chromosomal abnormalities and gene mutations have become major determinants in the classification of kidney carcinomas. Most renal medullary carcinomas develop in patients with hereditary sickle cell disease, but sporadic cases... more
Chromosomal abnormalities and gene mutations have become major determinants in the classification of kidney carcinomas. Most renal medullary carcinomas develop in patients with hereditary sickle cell disease, but sporadic cases unassociated with sickle cell disease have also been described, for which underlying genetic abnormality is unknown. We evaluated 3 patients with renal medullary carcinoma (1 patient with sickle cell disease and 2 patients without sickle cell disease) for germ line and somatic mutations in genes commonly involved in pathogenesis of renal carcinomas using denaturing high-performance liquid chromatography and direct sequencing. Chromosomal abnormalities were studied by the conventional cytogenetic and SNP arrays analysis. Expression of hypoxia-inducible factor 1α was examined using immunohistochemistry. Two new mutations in the gene for fumarate hydratase were identified in 1 case of medullary renal carcinoma without sickle cell disease: a germ line mutation in...
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ABSTRACT PURPOSE To evaluate the discrimination of benign from malignant prostate outer gland tissue during contrast-enhanced sonography. METHOD AND MATERIALS 301 subjects with an elevated PSA or abnormal digital rectal examination were... more
ABSTRACT PURPOSE To evaluate the discrimination of benign from malignant prostate outer gland tissue during contrast-enhanced sonography. METHOD AND MATERIALS 301 subjects with an elevated PSA or abnormal digital rectal examination were evaluated with transrectal sonography during infusion of a microbubble contrast agent (Imagent; Imcor). Baseline imaging was performed with conventional gray scale, color and power Doppler. Contrast-enhanced imaging was performed with harmonic gray scale, including continuous harmonic imaging (CHI) and intermittent haramonic imaging (IHI) with interscan delay times of 0.2s, 0.5s, 1.0s, 2.0s, as well as with continuous color and power Doppler. Six biopsy cores were obtained in a modified sextant distribution with one core from the most suspicious area in each sextant. A sextant with no suspicious area was sampled with a laterally directed core. Each biopsy site was prospectively rated for suspicion of cancer on a 1-5 scale with each imaging technique. In order to compensate for clustering of data within each subject, clustered ROC analysis was performed. RESULTS Cancer was detected in 188 sextant cores from 93 of 301 subjects (31%). Clustered ROC analysis demonstrated the following values for area under the curve, Az: pre-contrast gray scale � 0.58, pre-contrast color Doppler � 0.53, pre-contrast power Doppler � 0.58, CHI � 0.62, IHI (0.2s) � 0.64, IHI (0.5s) � 0.63, IHI (1.0s) � 0.65, IHI (2.0s) � 0.61, contrast-enhanced color Doppler � 0.60, contrast enhanced power Doppler � 0.62. A statistically significant benefit was found for IHI over baseline gray scale and Doppler imaging (p < 0.05). CONCLUSIONS Contrast-enhanced transrectal sonography with IHI provides a statistically significant improvement in discrimination between benign and malignant areas of the prostate outer gland. However, as evidenced by relatively low ROC areas, contrast enhanced sonography cannot definitively differentiate benign from malignant tissue without biopsy confirmation.