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Biomedical subjects

M Shalev

Publications and source records attributed to M Shalev.

At least 19 recordsLinked to original sources
PubMed2001

Phase I/II trial evaluating combined radiotherapy and in situ gene therapy with or without hormonal therapy in the treatment of prostate cancer--a preliminary report.

PURPOSE: To report the preliminary results of a Phase I/II study combining radiotherapy and in situ gene therapy (adenovirus/herpes simplex virus thymidine kinase gene/valacyclovir) with or without hormonal therapy in the treatment of prostate cancer. METHODS AND MATERIALS: Arm A: low-risk patients (T1-T2a, Gleason score <7, pretreatment PSA <10) were treated with combined radio-gene therapy. A mean dose of 76 Gy was delivered to the prostate with intensity-modulated radiotherapy. Arm B: high-risk patients (T2b-T3, Gleason score >or=7, pretreatment PSA >or=10) were treated with combined radio-gene therapy and hormonal therapy. Hormonal therapy was comprised of a 4-month leuprolide injection and 2-week use of flutamide. Arm C: Stage D1 (positive pelvic lymph node) patients received the same regimen as Arm B, with the additional 45 Gy to the pelvic lymphatics. Treatment-related toxicity was assessed using Cancer Therapy Evaluation Program common toxicity score and Radiation Therapy Oncology Group (RTOG) toxicity score. RESULTS: Thirty patients (13 in Arm A, 14 in Arm B, and 3 in Arm C) completed the trial. Median follow-up was 5.5 months. Eleven patients (37%) developed flu-like symptoms (Cancer Therapy Evaluation Program Grade 1) of fatigue and chills/rigors after gene therapy injection but recovered within 24 h. Four patients (13%) and 2 patients (7%) developed Grade 1 and 2 fever, respectively. There was no patient with weight loss. One patient in Arm B developed Grade 3 elevation in liver enzyme, whereas 11 and 2 patients developed Grade 1 and 2 abnormal liver function tests. There was no Grade 2 or above hematologic toxicity. Three patients had transient rise in creatinine. There was no RTOG Grade 3 or above lower gastrointestinal toxicity. Toxicity levels were as follows: 4 patients (13%), Grade 2; 6 patients (20%), Grade 1; and 20 patients (67%), no toxicity. There was 1 patient with RTOG Grade 3 genitourinary toxicity, 12 patients (40%) with Grade 2, 8 patients (27%) with Grade 1, and 9 patients (30%) with no toxicity. No patient dropped out from the trial or had to withhold treatment because of severe toxicity. CONCLUSIONS: This is the first trial of its kind in the field of prostate cancer that aims to expand the therapeutic index of radiotherapy by combining in situ gene therapy. Initial experience has demonstrated the safety of this approach. There is no added toxicity to each therapy used alone. Long-term follow-up and larger cohort studies are warranted to evaluate long-term toxicity and efficacy.

Adenoviridae↗
PubMed2001

Prostate-specific antigen response and systemic T cell activation after in situ gene therapy in prostate cancer patients failing radiotherapy.

In an extended phase I/II study we evaluated 36 prostate cancer patients with local recurrence after radiotherapy who received single or repeated cycles of replication-deficient adenoviral vector (ADV)-mediated herpes simplex virus-thymidine kinase (HSV-tk) plus ganciclovir (GCV) in situ gene therapy with respect to serum PSA levels, alterations in immune cells, and numbers of apoptotic cells in needle biopsies. An initial cycle of HSV-tk plus GCV gene therapy caused a significant prolongation of the mean serum PSA-doubling time (PSADT) from 15.9 to 42.5 months (p = 0.0271) and in 28 of the injected patients (77.8%) there was a mean PSA reduction (PSAR) of 28%. It took a mean of 8.5 months for the PSA to return to the initial PSA (TR-PSA) value. A repeated cycle of gene therapy failed to significantly extend PSADT but did result in significant increases in PSAR (29.4%) and TR-PSA (10.5 months). Moderately increased serum adenovirus antibody titers were generally observed 2 weeks after initial vector injection. Also at this time there was a statistically significant increase in the mean percent of CD8(+) T cells positive for the HLA-DR marker of activation in peripheral blood (p = 0.0088). Studies using prostate biopsies obtained at the same time point demonstrated that vector DNA was detectable by PCR in most samples yet all patients remained positive for prostate cancer in at least one biopsy core. Further analysis demonstrated a correlation between the level of CD8(+) cells and the number of apoptotic cells in biopsies containing cancer cells (p = 0.042). We conclude that repeated cycles of in situ HSV-tk plus GCV gene therapy can be administered to prostate cancer patients who failed radiotherapy and have a localized recurrence. Biological responses to this experimental therapy including increases in PSADT, PSAR, and TR-PSA, and activated CD8(+) T cells present in the peripheral blood, were demonstrated. Interestingly, the density of CD8(+) cells in posttreatment biopsies correlated with the number of apoptotic cells.

Adenoviridae↗
PubMed2001

Preoperative plasma levels of transforming growth factor beta(1) (TGF-beta(1)) strongly predict progression in patients undergoing radical prostatectomy.

PURPOSE: Elevated local and circulating levels of transforming growth factor beta(1) (TGF-beta(1)) have been associated with prostate cancer invasion and metastasis. We tested the hypothesis that preoperative plasma TGF-beta(1) levels would independently predict cancer stage and prognosis in patients who undergo radical prostatectomy. PATIENTS AND METHODS: The study group consisted of 120 consecutive patients who underwent radical prostatectomy for clinically localized prostate cancer (median follow-up, 53.8 months). Preoperative plasma levels of TGF-beta(1) were measured and correlated with pathologic parameters and clinical outcomes. TGF-beta(1) levels also were measured in 44 healthy men without cancer, in 19 men with prostate cancer metastatic to regional lymph nodes, and in 10 men with prostate cancer metastatic to bone. RESULTS: Plasma TGF-beta(1) levels in patients with lymph node metastases (14.2 +/- 2.6 ng/mL) and bone metastases (15.5 +/- 2.4 ng/mL) were higher than those in radical prostatectomy patients (5.2 +/- 1.3 ng/mL) and healthy subjects (4.5 +/- 1.2 ng/mL) (P <.001). In a preoperative analysis, preoperative plasma TGF-beta(1) level and biopsy Gleason sum both were predictors of organ-confined disease (P =.006 and P =.006, respectively) and PSA progression (P <.001 and P =.021, respectively). In a postoperative multivariate analysis, preoperative plasma TGF-beta(1) level, pathologic Gleason sum, and surgical margin status were predictors of PSA progression (P =.020,P =.020, and P =.022, respectively). In patients who progressed, preoperative plasma TGF-beta(1) levels were higher in those with presumed distant compared with local-only failure (P =.019). CONCLUSION: Plasma TGF-beta(1) levels are markedly elevated in men with prostate cancer metastatic to regional lymph nodes and bone. In men without clinical or pathologic evidence of metastases, the preoperative plasma TGF-beta(1) level is a strong predictor of biochemical progression after surgery, presumably because of an association with occult metastatic disease present at the time of radical prostatectomy.

Adult↗
PubMed2001

Intracavernous injections: still the gold standard for treatment of erectile dysfunction in elderly men.

The objective of this work was to determine the effectiveness of intracavernous injections (ICI) of vasoactive drugs in elderly men with erectile dysfunction and to compare the results obtained with the injection of two different drug combinations. It was a case control study. The sample consisted of 300 men, 63-85 y of age (mean 67.1) with erectile dysfunction of organic origin. Among the patients 180 underwent first trial with injection of prostaglandin E1 (PE). Further on these 180 patients and another 120 (in total 300 patients) were treated with a triple combination of papaverine hydrochlorate, phentolamine messylate and prostaglandin E1 (PPR). The number of responders to the injection of either PE alone or the drug combination was recorded. The quality of the erections was evaluated in the outpatient clinic by the medical staff and through patient's report after home trial. The average volume of either PE or PPR necessary to obtain a functional erection was measured. We observed a statistically significant association between the results obtained after the injection of PPR as compared to PE (chi2 with 2 d.f.: 34.666; P= < 0.001). A functional erection was obtained in 224/300 (74.7%) after the injection of PPR as compared to 87/180 men (48.3%) treated with PE. The average volume of PPR necessary to obtain a functional erection was 0.35+/-0.14 ml whereas that of PE was 1.3+/-0.3 ml. intracavernous injection of vasoactive drugs is still one of the most successful therapies for patients suffering from organic impotence. It is less effective in the older age group as compared to younger. However, if this form of therapy is chosen for aged men the triple combination therapy (PPR) yields a higher response rate than that obtained with prostaglandin alone.

Aged↗
PubMed2001

The prognostic value of DNA ploidy in small renal cell carcinoma.

The objective was to study the prognostic value of Deoxyribonucleic Acid (DNA) ploidy status in small renal cell carcinomas (RCC). The nuclear DNA content of renal cell carcinoma tissues from patients who underwent radical or partial nephrectomy has been analyzed by flow cytometry. The results of the DNA ploidy have been correlated to the size of tumors and disease progression. Of the 50 patients with RCC studied, 8 (16%) progressed. Tumors with non-diploid DNA patterns were found in 24 (48%) of the 50 patients and in 4 of the 8 patients who progressed. Overall the median tumor size in our series was 50 mm. A tumor diameter of 50 mm or less was measured in 26 patients (group I) and above 50 mm in 24 (group II). Non-diploid DNA patterns were found in 11 (42.3%) and 13 (54.2%) patients in groups I and II, respectively. This difference between the groups was not significant. Only one patient in group I (3.8%) developed metastatic disease and died 72 months after the operation. In group II, 7 patients (29.2%) presented tumor progression and 5 died of metastatic disease. The survival probability in group I was 95% at 5 and 8 years (95% CI 70% to 99%) and for group II 94% at 5 years (95% CI 67%-99%) and 67% at 8 years (95% CI 39%-83%). DNA ploidy is an inaccurate predictor of tumor behavior in patients with RCC, even in small tumors. Tumor size is a more significant predictor of outcome.

Adult↗