Citations

Abstract Rationale: Mycobacterium avium complex pulmonary disease (MAC-PD) is associated with substantial morbidity, and standard daily multidrug therapy is difficult to tolerate. Objectives To characterize response to a three-times-weekly (TIW) regimen of clarithromycin, ethambutol, and rifampin. Methods A 1-yr prospective noncomparative trial of TIW treatment was conducted during 2000–2003 in 17 U.S. cities. Participants were 91 HIV-negative adults, diagnosed with moderate to severe MAC-PD, who originally participated in a trial of an inhaled IFN-γ treatment. Improvement in sputum culture, high-resolution computed tomography (HRCT), and symptoms were assessed. Results Treatment response rates (and median response times) were 44% (2 mo or longer) for culture, 60% (5.5–11.5 mo) for HRCT, and 53% (8.5 mo) for symptoms. Having noncavitary, compared with cavitary, disease increased culture response by 4.0 times (95% confidence interval [CI], 1.7–9.2) and HRCT response by 4.9 times (95% CI, 1.9–13.0). Culture response was 1.5 times (95% CI, 1.1–2.2) higher for older subjects and 2.2 times (95% CI, 1.0–4.7) higher for previously untreated subjects. Being smear-negative increased culture response by 2.3 times (95% CI, 1.1–5.2) but decreased HRCT response by 4.4 times (95% CI, 1.7–11.5). Increasing ethambutol use by 5 mo increased culture response by 1.5 times (95% CI, 1.0–2.1) but decreased symptom response. Not having chronic obstructive pulmonary disease, bronchiectasis, or poor lung function increased symptom response by 1.9 to 3.9 times. Conclusions TIW therapy was less effective for MAC-PD patients with cavitary disease and a history of chronic obstructive pulmonary disease, bronchiectasis, or previous treatment for MAC-PD. Further research is needed to study the long-term outcomes of TIW treatment.

Abstract Purpose: Prostate stem cell antigen (PSCA) is expressed by a majority of prostate cancers and is a promising therapeutic target. PSCA protein and mRNA expression was examined in prostate cancer bone, lymph node, and visceral metastases to assess the potential of PSCA as an immunotherapeutic target in advanced prostate cancer. Experimental Design: Immunohistochemical analysis of PSCA protein expression and quantitative mRNA expression analysis of PSCA was done on clinical specimens of prostate cancer bone, lymph node, and visceral metastases. PSCA protein and mRNA expression levels were quantified and compared between available matched pairs of bone and lymph node or visceral metastases. Results: Bone metastases stained with higher intensity of PSCA compared with lymph node or liver metastases in seven of eight (87.5%) matched pairs (P = 0.035). PSCA mRNA expression was equal or greater than that of LAPC-9, a PSCA expressing xenograft, in 12 of 24 (50%) cases of prostate cancer metastases and was significantly correlated with PSCA protein expression (σ = 0.84, P = 0.0019). Overall, PSCA protein expression was detected in 41 of 47 (87.2%), four of six (66.7%), and two of three (66.7%) cases of bone, lymph node, and liver metastases, respectively. Mean PSCA staining intensity was significantly higher in prostate cancer bone metastases compared with lymph node metastases (2.0 ± 0.02 versus 0.83 ± 0.31, P = 0.014). Conclusions: Prostate cancer metastases express PSCA. However, greater PSCA staining intensity and level of PSCA mRNA expression was associated with bone metastases compared with lymph node metastases. This study suggests that PSCA is a promising tumor marker and potential therapeutic target for patients with metastatic prostate cancer.