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Biomedical subjects

Thomas A Gardner

Publications and source records attributed to Thomas A Gardner.

At least 19 recordsLinked to original sources

Adenoviral vectors expressing human endostatin-angiostatin and soluble Tie2: enhanced suppression of tumor growth and antiangiogenic effects in a prostate tumor model.

Angiogenesis is essential for prostate cancer development and metastasis. Antiangiogenic therapy targeting tumor neovasculature, therefore, represents a promising approach for prostate cancer treatment. We hypothesized that adenoviral-mediated delivery of a combination of antiangiogenic factors might have an enhanced antitumor response. We developed the adenoviral vectors Ad-hEndo-angio, expressing a unique, chimeric human endostatin-angiostatin fusion protein, and Ad-sTie2, expressing a soluble form of endothelium-specific receptor tyrosine kinase Tie2. Matrigel angiogenesis assays using Ad-hEndo-angio revealed significant inhibition of tubular network formation and endothelial sprouting compared to Ad-sTie2. In vivo studies in a bilateral PC-3 tumor xenograft model following either intratumoral or systemic administration of Ad-hEndo-angio led to enhanced tumor growth suppression compared to Ad-sTie2. A novel finding is that an intratumoral, combination therapy employing one-half the dose of Ad-hEndo-angio as well as Ad-sTie2 led to a complete regression of the injected, as well as the contralateral uninjected, tumor and prolonged the tumor-free survival in 80% of the animals. In addition, a novel, real-time, intravital imaging modality was used to monitor antiangiogenic responses following adenoviral-mediated gene transfer. These results suggest that a combinatorial antiangiogenic gene therapy approach involving Ad-hEndo-angio and Ad-sTie2 could become a novel form of treatment for localized human prostate cancer.

Adenoviridae↗

The combined percentage of Gleason patterns 4 and 5 is the best predictor of cancer progression after radical prostatectomy.

PURPOSE: Clinical outcome is variable in prostate cancer patients treated with radical prostatectomy. The Gleason histologic grade of prostatic adenocarcinoma is one of the strongest predictors of biologic aggressiveness of prostate cancer. We evaluated the significance of the relative proportion of high-grade cancer (Gleason patterns 4 and/or 5) in predicting cancer progression in prostate cancer patients treated with radical prostatectomy. PATIENTS AND METHODS: Radical prostatectomy specimens from 364 consecutive prostate cancer patients were totally embedded and whole mounted. Various clinical and pathologic characteristics were analyzed. All pathologic data, including Gleason grading variables, were collected prospectively. RESULTS: A multiple-factor analysis was performed that included the combined percentage of Gleason patterns 4 and 5, Gleason score, tumor stage, surgical margin status, preoperative prostate-specific antigen (PSA), extraprostatic extension, and total tumor volume. Using Cox regression analysis with bootstrap resampling for predictor selection, we identified the combined percentage of Gleason patterns 4 and 5 (P < .0001) and total tumor volume (P = .009) as significant predictors of PSA recurrence. CONCLUSION: The combined percentage of Gleason patterns 4 and 5 is one of the most powerful predictors of patient outcome, and appears superior to conventional Gleason score in identifying patients at increased risk of disease progression. On the basis of our results, we recommend that the combined percentage of Gleason patterns 4 and 5 be evaluated in radical prostatectomy specimens. The amount of high-grade cancer in a prostatectomy specimen should be taken into account in therapeutic decision making and assessment of patient prognosis.

Adenocarcinoma↗

Gene therapy for prostate cancer by controlling adenovirus E1a and E4 gene expression with PSES enhancer.

PSES is a chimeric enhancer containing enhancer elements from prostate-specific antigen (PSA) and prostate-specific membrane antigen (PSMA) genes that are prevalently expressed in androgen-independent prostate cancers. PSES shows strong activity equivalent to cytomegalovirus (CMV) promoter, specifically in PSA/PSMA-positive prostate cancer cells, the major cell types in prostate cancer in the absence of androgen. We developed a recombinant adenovirus (AdE4PSESE1a) by placing adenoviral E1a and E4 genes under the control of the bidirectional enhancer PSES and enhanced green fluorescent protein gene for the purpose of intratumoral virus tracking under the control of CMV promoter. Because of PSES being very weak in nonprostatic cells, including HEK293 and HER911 that are frequently used to produce recombinant adenovirus, AdE4PSESE1a can only be produced in the HER911E4 cell line which expresses both E1 and E4 genes. AdE4PSESE1a showed similar viral replication and tumor cell killing activities to wild-type adenovirus in PSA/PSMA-positive prostate cancer cells. The viral replication and tumor cell killing activities were dramatically attenuated in PSA/PSMA-negative cells. To test whether AdE4PSESE1a could be used to target prostate tumors in vivo, CWR22rv s.c. tumors were induced in nude mice and treated with AdE4PSESE1a via intratumoral and tail vein injection. Compared to tumors treated with control virus, the growth of CWR22rv tumors was dramatically inhibited by AdE4PSESE1a via tail vein injection or intratumoral injection. These data show that adenoviral replication can be tightly controlled in a novel fashion by controlling adenoviral E1a and E4 genes simultaneously with a single enhancer.

Adenoviridae↗

Synthesis of 2-amino-6-(4-[11C]methoxyphenylthio)-9-[2-(phosphonomethoxy)ethyl]purine bis(2,2,2-trifluoroethyl) ester as a novel potential PET gene reporter probe for HBV and HSV-tk in cancers.

Acyclic nucleoside 2-amino-6-(4-methoxyphenylthio)-9-[2-(phosphonomethoxy)ethyl]purine bis(2,2,2-trifluoroethyl) ester (ABE, 1) is a new hepatitis B virus (HBV) specific antiviral reagent and shows high anti-HBV activity. Carbon-11 labeled ABE may serve as a novel reporter probe for positron emission tomography (PET) to image HBV and herpes simplex virus thymidine kinase (HSV-tk) in cancers. The radiolabeling precursors 2-amino-6-(4-hydroxyphenylthio)-9-[2-(phosphonomethoxy)ethyl]purine bis(2,2,2-trifluoroethyl) ester (10) and 2-N-Boc protected analogue 2-N-bis(Boc)amino-6-(4-hydroxyphenylthio)-9-[2-(phosphonomethoxy)ethyl]purine bis(2,2,2-trifluoroethyl) ester (12), and the reference standard ABE were synthesized from bis(trifluoroethyl) (2-iodoethoxy)methylphosphonate (5), guanine (6), and 2-amino-6-chloropurine (8). The target radiotracer 2-amino-6-(4-[11C]methoxyphenylthio)-9-[2-(phosphonomethoxy)ethyl]purine bis(2,2,2-trifluoroethyl) ester ([11C]ABE, [11C]1) was prepared by O-[11C]methylation of the unprotected HO-precursor 10, or 2-N-Boc protected HO-precursor 12 with [11C]methyl triflate followed by a quick deprotection reaction, and isolated by solid-phase extraction (SPE) purification in 40-55% radiochemical yields.

Antiviral Agents↗

Thermal-based treatment options for localized prostate cancer.

It seems clear that thermal-based therapies of prostate cancer have the potential to completely eradicate the prostate gland. Technical modifications continue to improve our ability to use these modalities more effectively, which can be seen in the ever decreasing morbidity from damage to adjacent structures. These treatments offer potential major advantages over surgery and radiation-based treatment modalities.

Cryotherapy↗

Elevated activated partial thromboplastin time during administration of first-generation adenoviral vectors for gene therapy for prostate cancer: identification of lupus anticoagulants.

OBJECTIVES: To evaluate the cause and significance of elevated activated partial thromboplastin time (aPTT) in a group of patients who received a first-generation adenoviral vector (Ad-OC-TK) delivering a toxic gene to prostate cancer cells as part of a Phase I clinical trial at the University of Virginia. METHODS: Eleven subjects were injected intratumorally to metastatic lesions of prostate cancer in the prostatic fossa, retroperitoneal lymph nodes, or bone (iliac, ischium, or vertebrae). After the initial laboratory evaluation, patients with elevated aPTT underwent a series of additional tests, including mixing studies, coagulation factor, prekallikrein, and high-molecular-weight kininogen, and lupus anticoagulant studies (modified Russell viper venom time) with phospholipid correction, and a Staclot LA assay. RESULTS: Of the 11 subjects who were enrolled in the trial, 6 had elevated aPTT values. Of the 6 patients, 3 had aPTT elevation of more than 10 seconds above normal. Two of the subjects with higher values demonstrated an inhibitory pattern with the factor VIII and XI assays, and the lupus anticoagulant studies were positive. No clinical sequelae to the elevated aPTT values were observed. CONCLUSIONS: This is, to our knowledge, the first formal report of a first-generation adenoviral vector causing a slight transient elevation of the aPTT through the induction of an antiphospholipid antibody. No clinical sequelae related to elevated aPTT values were observed. The adenoviral protocol was safe; similar protocols should be aware of this phenomenon.

Adenoviridae↗

Pulmonary sequestration presenting as retroperitoneal cyst: case report.

A 21-year-old woman presented with flank pain, and an abdominal and pelvic CT scan demonstrated a left 7.4-cm simple cyst superior to the left kidney. She underwent laparoscopic cyst decortication complicated by a diaphragmatic injury and pneumothorax. The final pathology report described a retroperitoneal pulmonary sequestration (RPS). Urologists need to consider RPS in the differential diagnosis of a retroperitoneal cyst because of the associated morbidity of hemorrhage during surgical excision. With the widespread use abdominal imaging techniques, more cases of RPS are likely to be identified and referred for laparoscopic management.

Adult↗

Is it necessary to separate clinical stage T1c from T2 prostate adenocarcinoma?

OBJECTIVE: To test the hypothesis that prostate cancer patients with clinical stage cT1c and cT2 have similar outcomes and clinicopathological features, and should be grouped together. PATIENTS AND METHODS: From a series of men with prostate cancer who had a radical retropubic prostatectomy (RP), we assessed those with cT1c (223) and cT2 (65) adenocarcinoma. All RP specimens were totally embedded and whole-mounted; tumour volume was measured using the grid method. Clinical and pathological characteristics were analysed. RESULTS: Patients with cT2 tumours were more likely to have a higher Gleason score (P = 0.04) and final pathological stage (P = 0.05) than those with cT1c tumours. There was no significant difference in age (P = 0.92), preoperative PSA level (P = 0.17), prostate weight (P = 0.34), tumour volume (P = 0.16), surgical margin status (P = 0.86), multifocality (P = 0.92), the presence of perineural invasion (P = 0.09), or high-grade prostatic intraepithelial neoplasia (P = 0.99) between patients with clinical stage cT1c and those with cT2 tumours. There was no difference in PSA recurrence between patients with clinical stage T1c and those with cT2 tumours (P = 0.27). CONCLUSIONS: Patients with clinical stage cT2 tumours have a higher Gleason score and advanced pathological stage than tumours detected because of a high serum PSA level (cT1c). These results suggest that clinical stage cT1c tumours should be separated from clinical stage cT2 disease, but the PSA recurrence rate for both tumour stages is similar, indicating a need for further evaluation and refinement of the current clinical staging system.

Adenocarcinoma↗

Transcriptional targeting modalities in breast cancer gene therapy using adenovirus vectors controlled by alpha-lactalbumin promoter.

The breast-specific antigen alpha-lactalbumin is expressed in >60% of breast cancer tissues. To evaluate the effect of gene therapy for breast cancer by controlling adenovirus replication with human alpha-lactalbumin promoter, we investigated the activity of a 762-bp human alpha-lactalbumin promoter. Alpha-lactalbumin promoter showed significantly higher activity in MDA-MB-435S and T47D breast cancer cells than in normal breast cell lines or other tumor cell lines. We then developed two novel breast cancer-restricted replicative adenoviruses, AdALAE1a and AdE1aALAE1b. In AdALAE1a, expression of adenoviral E1a gene is under the control of alpha-lactalbumin promoter, and in AdE1aALAE1b, expression of both E1a and E1b genes is under the control of a single alpha-lactalbumin promoter. Both breast cancer-restricted replicative adenoviruses showed viral replication efficiency and tumor cell-killing capability similar to wild-type adenovirus in MDA-MB-435S and T47D cells. The replication efficiency and tumor cell-killing capability of both viruses were attenuated significantly in cells that did not support alpha-lactalbumin promoter. AdE1aALAE1b showed better breast cancer-restricted replication than AdALAE1a, suggesting that a transcriptional targeting modality with alpha-lactalbumin promoter controlling both E1a and E1b gene expression is superior to alpha-lactalbumin promoter controlling only E1a gene expression. Importantly, we found that AdE1aALAE1b could be used to target hormone-independent breast tumors in vivo by inhibiting the growth of MDA-MB-435S s.c. tumors. These data showed that alpha-lactalbumin promoter could regulate the replication of adenovirus to target hormone-independent breast cancers, suggesting that alpha-lactalbumin promoter can be used to develop a novel therapeutic modality for hormone-independent breast cancer.

Adenoviridae↗

Aberrant expression of CARM1, a transcriptional coactivator of androgen receptor, in the development of prostate carcinoma and androgen-independent status.

BACKGROUND: Coactivator-associated arginine methyltransferase 1 (CARM1) is a transcriptional coactivator of the androgen receptor (AR). It is involved in the regulation of the biologic functions of the AR. It remains to be determined whether CARM1 is involved in prostatic carcinogenesis. METHODS: The expression of CARM1 in normal prostate epithelium, high-grade prostatic intraepithelial neoplasia (PIN), and prostate carcinoma tissue was examined in 66 previously untreated patients with prostate carcinomas, as well as 12 patients with hormone-independent prostate carcinoma, using immunohistochemical methods. RESULTS: Cell staining was observed in the cytoplasm and the nucleus. In 66 patients without previous hormonal treatment, the percentage of cells that stained positively for CARM1 in benign prostate tissue specimens (mean values: cytoplasm, 23%; nucleus, 16%) was statistically significantly less than the percentage of positively stained cells in PIN (mean values: cytoplasm, 56%; nucleus, 30%; P < 0.001) and in prostatic adenocarcinoma specimens (mean values: cytoplasm, 79%; nucleus, 53%; P < 0.001). The difference between adenocarcinoma and PIN also was statistically significant (P < 0.001). The staining intensity for CARM1 was significantly lower in benign prostate tissue specimens compared with PIN and prostatic adenocarcinoma specimens (P < 0.001). In the 12 patients with androgen-independent prostatic adenocarcinoma, the expression of CARM1 was significantly increased when compared with patients without previous hormonal treatment. Expression of CARM1 was not correlated with age, Gleason score sum, pathologic stage, lymph node metastasis, extraprostatic extension, surgical margin status, vascular invasion, or perineural invasion. CONCLUSIONS: The authors found that overexpression of CARM1 was involved in the development of prostate carcinoma as well as androgen-independent prostate carcinoma. Since CARM1 is functionally different from most other transcriptional coactivators of the AR, it may serve as a new target for the treatment of hormone-independent prostate carcinoma.

Adenocarcinoma↗

[11C]Choline as a PET biomarker for assessment of prostate cancer tumor models.

[(11)C]Choline has been evaluated as a positron emission tomography (PET) biomarker for assessment of established human prostate cancer tumor models. [(11)C]Choline was prepared by the reaction of [(11)C]methyl triflate with 2-dimethylaminoethanol (DMAE) and isolated and purified by solid-phase extraction (SPE) method in 60-85% yield based on [(11)C]CO(2), 15-20 min overall synthesis time from end of bombardment (EOB), 95-99% radiochemical purity and specific activity >0.8 Ci/micromol at end of synthesis (EOS). The biodistribution of [(11)C]choline was determined at 30 min post iv injection in prostate cancer tumor models C4-2, PC-3, CWR22rv, and LNCaP tumor-bearing athymic mice. The results showed the accumulation of [(11)C]choline in these tumors was 1.0% dose/g in C4-2 mouse, 0.4% dose/g in PC-3 mice, 3.2% dose/g in CWR22rv mice, and 1.4% dose/g in LNCaP mice; the ratios of tumor/muscle (T/M) and tumor/blood (T/B) were 2.3 (T/M, C4-2), 1.4 (T/M, PC-3), 2.5 (T/M, CWR22rv), 1.2 (T/M, LNCaP) and 2.6 (T/B, C4-2), 2.6 (T/B, PC-3), 7.8 (T/B, CWR22rv), 3.2 (T/B, LNCaP), respectively. The micro-PET imaging of [(11)C]choline in prostate cancer tumor models was acquired from a C4-2, PC-3, CWR22rv, or LNCaP implanted mouse at 30 min post iv injection of 1 mCi of the tracer using a dedicated high resolution (<3 mm full-width at half-maximum) small FOV (field-of-view) PET imaging system, IndyPET-II scanner, developed in our laboratory, which showed the accumulation of [(11)C]choline in C4-2, PC-3, CWR22rv, or LNCaP tumor implanted in a nude athymic mouse. The initial dynamic micro-PET imaging data indicated the average T/M ratios were approximately 3.0 (C4-2), 2.1 (PC-3), 3.5 (CWR22rv), and 3.3 (LNCaP), respectively, which showed the tumor accumulation of [(11)C]choline in all four tumor models is high. These results suggest that there are significant differences in [(11)C]choline accumulation between these different tumor types, and these differences might offer some useful measure of tumor biological process.

Animals↗

Development of human chorionic gonadotropin subunit-beta promoter-based toxic gene therapy for testicular cancer.

OBJECTIVES: To develop a new toxic gene therapy using the tissue-specific human chorionic gonadotropin-beta (hCG-beta) promoter for testicular cancer. Although most patients presenting with disseminated testicular tumor are cured through the use of chemotherapy with or without surgery, those patients with relapse after initial therapy present a difficult clinical problem. The serum tumor marker hCG-beta is frequently elevated in patients with testicular cancer, and the pretreatment and post-treatment levels of serum hCG-beta are highly predictive of treatment outcome. METHODS: Human testicular embryonal carcinoma cell line, NEC 8, a human prostate cancer cell line, PC-3, and a human bladder cancer cell line, WH, were used in this study. A transient expression experiment was used to analyze the activity of a 729-bp hCG-beta promoter in all three cell lines. A recombinant adenovirus carrying thymidine kinase (Ad-hCG-beta-TK) under control of the hCG-beta promoter was generated. The tissue-specific activity of Ad-hCG-beta-TK was tested in vitro and in vivo. RESULTS: The hCG-beta promoter had significantly greater activity in the hCG-beta-producing cell line (NEC 8) than in the non-hCG-beta-producing cell lines (PC-3 and WH). In vitro, Ad-hCG-beta-TK with acyclovir significantly inhibited NEC 8 growth but not PC-3 or WH cell growth. In vivo, Ad-hCG-beta-TK with acyclovir significantly inhibited NEC 8 subcutaneous tumor growth in nude mice. CONCLUSIONS: In this study, we explored the possibility of developing a new therapeutic agent to target and induce the killing of testicular germ cell tumor selectively by using tissue-specific hCG-beta promoters.

Acyclovir↗

Cotargeting tumor and stroma in a novel chimeric tumor model involving the growth of both human prostate cancer and bone stromal cells.

Stromal-epithelial interaction contributes to local prostate tumor growth, androgen-independent progression and distant metastasis. We have established in vitro coculture and in vivo chimeric tumor models to evaluate the roles of stromal cells isolated from either osteosarcoma or normal bone, a site where prostate cancer cells frequently metastasize, in contributing to the growth and survival of human prostate cancer cells. We have evaluated extensively the effects of toxic gene therapy using luciferase-tagged chimeric human prostate cancer models both in vitro and in vivo. In the in vitro cocultured cell model, we assessed cancer cell growth and residual cellular proteins after targeting either prostate cancer epithelial cells alone or both prostate cancer and bone stromal cells. In the in vivo animal model, we measured tumor volume and serum prostate-specific antigen (PSA) in mice bearing chimeric prostate tumors comprised of human prostate tumor cells and normal bone stromal cells. Our results demonstrated that: (1) The rate of human prostate cancer cell growth in vitro is accelerated by coculturing with human and rat osteosarcoma or normal mouse bone marrow stromal cell lines. No growth stimulation was noted when cocultured with a human prostate epithelial cell line. (2) Disabling the growth of normal bone stromal cells using transgenic targeting with a bystander gene, herpes simplex virus thymidine kinase (hsv-TK), plus the pro-drug ganciclovir (GCV) or acyclovir markedly depressed the growth of cocultured human prostate cancer cells in vitro and human prostate cancer-mouse normal bone stroma chimeric tumors in vivo. (3) By cotargeting both human prostate cancer and normal mouse bone stromal cells in vitro with an adenoviral construct, Ad-hOC-TK (a replication-defective Ad5 vector with the bystander transgene hsv-TK under the control of a human osteocalcin (hOC) promoter) plus GCV4, we observed greater inhibition of tumor cell growth than by targeting a single cell compartment with Ad-PSA-TK (a vector construct similar to Ad-hOC-TK except that the transgene expression is under regulation by a full-length human PSA promoter). These results, taken together, established a basic principle that cotargeting both tumor and its supporting stroma is more efficacious than targeting a single cell compartment in the treatment of human prostate cancer bone metastasis. This principle can be applied to other clinical conditions of cancer growth where stroma contribute to the overall growth and survival potential of the cancer.

Adenoviridae↗

Tumor-specific gene therapy for uterine cervical cancer using MN/CA9-directed replication-competent adenovirus.

Although gene therapies using tissue-specific promoters have been reported to be a promising tool for treating cancers, few studies have explored this possibility for uterine cervical cancer. MN/CA9 is a transmembrane glycoprotein that was first identified in the human cervical carcinoma cell line, HeLa. Since MN/CA9 protein is highly expressed in uterine cervical cancer tissues, but not in normal cervix, we constructed a tumor-specific replication-competent adenoviral vector utilizing MN/CA9 promoter (Ad-MN/CA9-E1a), which can replicate only in MN/CA9-expressing cells. Infection of Ad-MN/CA9-E1a to MN/CA9-positive uterine cervical cancer cells (HeLa, C-33 A and SiHa) resulted in much stronger Ad5 E1a protein expressions compared with MN/CA9-negative cells (SK-RC-29), suggesting a tissue-specific replication of this recombinant adenovirus. In vitro cytotoxicity assay revealed that the growth of MN/CA9-positive cells was significantly inhibited with 0.01-1 MOI of Ad-MN/CA9-E1a, but the growth of MN/CA9-negative cells (SK-RC-29) could only be inhibited by as many as 100 MOI. Intratumoral injection of Ad-MN/CA9-E1a effectively induced growth delay of HeLa tumors in nude mice. These results suggest that a novel replication-competent adenoviral vector mediated by MN/CA9 promoter, Ad-MN/CA9-E1a, can selectively replicate in MN/CA9-expressing tumors with cytotoxic effects and may be utilized for the treatment of uterine cervical cancer.

Adenoviridae↗

Transitional cell carcinoma of the bladder following augmentation cystoplasty for the neuropathic bladder.

PURPOSE: Cancer following augmentation cystoplasty is a recognized risk factor. The procedure has only gained popularity in pediatric urology within the last 25 years, limiting the population being studied by statistical power and the lack of long-term followup. The majority of reported cases of post-augmentation malignancy have occurred in adults with multiple risk factors. Currently the most common indication for augmentation cystoplasty in children and adolescents is neuropathic bladder. We review 3 cases of transitional cell carcinoma (TCC) following augmentation cystoplasty in this unique population with no additional risk factors for bladder cancer. MATERIALS AND METHODS: We reviewed our clinical database of children and adolescents who underwent bladder augmentation since 1978 to evaluate the incidence of cancer. This study represents a captured population within a single institutional practice. There were 483 cases entered into the database, and particular attention was paid to 260 augmentations with at least 10 years of followup. We reviewed medical history, clinical outcomes, cancer risk factors, augmentation type and pathology of the 3 patients who presented with TCC after augmentation cystoplasty. RESULTS: Three patients presented with grade 2 to 3 TCC following bladder augmentation, all of whom underwent exploratory laparotomy and eventually died of metastatic disease. No patient had a history of smoking exposure greater than 10 packs per year or other known risk factors for bladder cancer. Two patients had an ileocecal augmentation and 1 had a cecal augmentation for neuropathic bladder. Patient age at augmentation was 8, 20 and 24 years, and age at diagnosis of TCC was 29, 37 and 44 years, respectively. Mean time from augmentation to TCC was 19 years. Assuming a 10-year lag period before the risk of cancer, in at least 1.2% of bladder augmentation cases in our database cancer has developed. CONCLUSIONS: This study supports the hypothesis that bladder augmentation appears to be an independent risk factor for TCC, with a lag time of less than 20 years. We recommend endoscopic surveillance of all patients with a history of bladder augmentation beginning 10 years after initial surgery.

Adult↗

Allelic loss of the active X chromosome during bladder carcinogenesis.

CONTEXT: Previous studies have shown that loss of the X chromosome is involved in the carcinogenesis of certain human malignancies. OBJECTIVE: To determine whether X-linked allelic losses occur during bladder tumorigenesis and whether such losses involve the active or the inactive X chromosome. DESIGN: We analyzed the deletion status of the X-linked human androgen receptor gene locus in 6 female patients who underwent radical cystectomies for muscle-invasive urothelial carcinoma of the urinary bladder. Four patients had coexisting urothelial carcinoma in situ. Analysis for inactivation of the X chromosome was carried out in parallel. RESULTS: Three cases were informative. Invasive tumor samples showed loss of heterozygosity involving the active allele at the androgen receptor locus in all 3 positive cases, whereas carcinoma in situ showed nonrandom X chromosome inactivation but not allelic deletion. CONCLUSIONS: Our data suggest that allelic loss of the activated X chromosome is involved in bladder carcinogenesis and cancer progression.

Carcinoma↗

Anatomic distribution of periprostatic adipose tissue: a mapping study of 100 radical prostatectomy specimens.

BACKGROUND: Because the prostatic capsule is often indistinct, recognition of extraprostatic extension by carcinoma depends heavily on the identification of carcinoma cells in the periprostatic adipose tissue. However, the distribution of adipose tissue along the prostatic surfaces has not been studied extensively. METHODS: The authors analyzed the periprostatic adipose tissue in specimens from 100 patients treated with radical retropubic prostatectomy and bilateral pelvic lymphadenectomy for prostatecarcinoma. Each specimen was totally embedded and examined by the whole mount method. The presence or absence of adipose tissue on the anterior, posterior, right, and left surfaces of the prostate was determined and analyzed. RESULTS: Periprostatic adipose tissue was present on 48% of all prostatic surfaces examined. The distribution of periprostatic adipose tissue varied among the different surfaces of the prostate, with the anterior, posterior, right, and left surfaces showing 44%, 36%, 59%, and 57% adipose tissue, respectively. The amount of periprostatic adipose tissue was similar among specimens from operations performed by different surgeons (P = 0.72). However, nerve-sparing procedures resulted in less adipose tissue (46%) than non-nerve-sparing procedures (54%) (P = 0.01). CONCLUSIONS: Less than half of the prostatic surfaces examined were covered by adipose tissue. The absence of adipose tissue over large areas of the prostatic surface, especially the posterior surface, makes the evaluation of extraprostatic extension difficult and unreliable. Further refinement of the prostate carcinoma staging system is needed.

Adipose Tissue↗

Phase I dose escalation clinical trial of adenovirus vector carrying osteocalcin promoter-driven herpes simplex virus thymidine kinase in localized and metastatic hormone-refractory prostate cancer.

Osteocalcin (OC), a major noncollagenous bone matrix protein, is expressed prevalently in prostate cancer epithelial cells, adjacent fibromuscular stromal cells, and osteoblasts in locally recurrent prostate cancer and prostate cancer bone metastasis [Matsubara, S., Wada, Y., Gardner, T.A., Egawa, M., Park, M.S., Hsieh, C.L., Zhau, H.E., Kao, C., Kamidono, S., Gillenwater, J.Y., and Chung, L.W. (2001). Cancer Res. 61, 6012-6019]. We constructed an adenovirus vector carrying osteocalcin promoter-driven herpes simplex virus thymidine kinase (Ad-OC-hsv-TK) to cotarget prostate cancer cells and their surrounding stromal cells. A phase I dose escalation clinical trial of the intralesional administration of Ad-OC-hsv-TK followed by oral valacyclovir was conducted at the University of Virginia (Charlottesville, VA) in 11 men with localized recurrent and metastatic hormone-refractory prostate cancer (2 local recurrent, 5 osseous metastasis, and 4 lymph node metastasis) in order to determine the usefulness of this vector for the palliation of androgen-independent prostate cancer metastasis. This is the first clinical trial in which therapeutic adenoviruses are injected directly into prostate cancer lymph node and bone metastasis. Results show that (1). all patients tolerated this therapy with no serious adverse events; (2). local cell death was observed in treated lesions in seven patients (63.6%) as assessed by TUNEL assay, and histomorphological change (mediation of fibrosis) was detected in all posttreated specimens; (3). one patient showed stabilization of the treated lesion for 317 days with no alternative therapy. Of the two patients who complained of tumor-associated symptoms before the treatment, one patient with bone pain had resolution of pain, although significant remission of treated lesions was not observed by image examination; (4). CD8-positive T cells were predominant compared with CD4-positive T cells, B cells (L26 positive), and natural killer cells (CD56 positive) in posttreated tissue specimens; (5). levels of HSV TK gene transduction correlated well with coxsackie-adenovirus receptor expression but less well with the titers of adenovirus injected; and (6). intrinsic OC expression and the efficiency of HSV TK gene transduction affected the levels of HSV TK protein expression in clinical specimens. Our data suggest that this form of gene therapy requires further development for the treatment of androgen-independent prostate cancer metastasis although histopathological and immunohistochemical evidence of apoptosis was observed in the specimens treated. Further studies including the development of viral delivery will enhance the efficacy of Ad-OC-hsv-TK.

Adenoviridae↗