Cisplatin, ifosfamide, oral etoposide, and concurrent accelerated hyperfractionated thoracic radiation for patients with limited small-cell lung carcinoma: results of radiation therapy oncology group trial 93-12.

PURPOSE: The combination of cisplatin, ifosfamide, and oral etoposide (PIEo) given concurrently with accelerated hyperfractionated thoracic radiation was studied in patients with limited small-cell lung cancer in a phase II trial to assess response, survival, and toxicity. PATIENTS AND METHODS: Sixty-seven patients were accrued between March 1994 and April 1996. Chemotherapy doses were cisplatin 20 mg/m(2) and ifosfamide 1,200 mg/m(2) on days 1 to 3 and etoposide 40 mg/m(2) administered orally days 1 through 14. Radiation consisted of accelerated hyperfractionated thoracic radiation (AHTRT) 1.5 Gy bid x 30 fractions (total 45 Gy) days 1 through 19, concurrent with cycle 1 of chemotherapy. Three additional cycles of chemotherapy were given every 4 weeks after completion of chemoradiation. Prophylactic cranial radiation (25 Gy in 10 fractions) was offered to patients for whom complete response (CR) after completion of chemotherapy was achieved. RESULTS: An overall objective response rate of 78% (41 CRs [67%] and seven partial responses [11%]) was seen in 61 patients whose disease response could be evaluated. Median progression-free and overall survival estimates were 12.7 and 23.7 months, respectively. Two- and 3-year survival rates were estimated at 50% and 39%, respectively. Major toxic effects included grade 4 granulocytopenia in 34 (55%), grade 4 thrombocytopenia in 16 (26%), grade 3 to 5 fever/infection in six (10%; with one death resulting from sepsis), and grade 3/4 esophagitis in 27 patients (43%). Other nonhematologic toxic greater than grade 2 occurred in 11 patients (18%). CONCLUSION: Relative to conventional etoposide/cisplatin and concurrent AHTRT, chemoradiation with PIEo produced similar median and 2-year survival rates and a higher rate of acute esophageal toxicity. However, the locoregional control rate with a minimum follow-up of 2 years is excellent at 80%. It is conceivable that longer follow-up will prove this regimen more promising. Research efforts should focus on other methods to improve disease control in all potential sites of recurrence.     

Multidrug resistance in a small cell lung cancer line: rapid selection with etoposide and differential chemosensitization with cyclosporin A.

We developed a multidrug resistant small cell lung cancer line, VPR-2, by exposing H69 parent cells to etoposide (20 microM) for 1 h daily for 3 days every 21-28 days, a schedule similar to that used in the clinic. Resistance (20-fold) to the cytostatic and DNA cleavage activities of etoposide emerged after the third treatment, and this phenotype was stable in the absence of drug exposure for 2.5 years. VPR-2 cells exhibited cross resistance to intercalating agents and vinca alkaloids, but remained sensitive to X-radiation, cisplatin and 5-fluorouracil. The human mdr1 gene was overexpressed in the resistant line, but steady-state concentrations of etoposide were reduced only 1.5-fold. Topoisomerase II catalytic and etoposide stimulated DNA cleavage activity in nuclear extracts from both lines were identical despite retention of a 3-fold level of resistance to etoposide-induced strand breaks in isolated nuclei from VPR-2 cells. Cyclosporin A and verapamil, both of which bind to P-glycoprotein, enhanced accumulation of etoposide in VPR-2 cells, and H69 cells to a lesser extent. Yet only cyclosporin A was effective in differentially enhancing etoposide cytostasis in VPR-2 relative to H69. In VPR-2 whole cells, cyclosporin A enhanced etoposide-induced DNA single-strand break frequency 9-fold but had no effect in isolated nuclei. Rapid selection of this line with a clinically relevant drug exposure schema and stability of the resistant phenotype suggest these cells may have been a steady subpopulation of the parent line through years of serial passage in vitro.(ABSTRACT TRUNCATED AT 250 WORDS)     

Participation of CD45, NKR-P1A and ANK61 antigen in rat hepatic NK cell (pit cell)mediated target cell cytotoxicity

AIM Several triggering receptors have been described to be involved in natural killer (NK) cellmediated target cytotoxicity. In these studies, NK cells derived from blood or spleen were used. Pit cells are liver-specific NK cells that possess a higher level of natural cytotoxicity and a different morphology when compared to blood NK cells. The aim of this study was to characterize the role of the NK-triggering molecules NKR-P1A, ANK61 antigen, and CD45 in pit cell-mediated killing of target cells. METHODS 51 Cr-release and DNA fragmentation were used to quantify target cell lysis and apoptosis, respectively. RESULTS Flow cytometric analysis showed that pit cells expressed CD45, NKR-P1A, and ANK61 antigen. Treatment of pit cells with monoclonal antibody ( mAb ) to CD45 ( ANK74 ) not only inhibited CC531s or YAC-1 target lysis but also apoptosis induced by pit cells. The mAbs to NKRP1A (3.2.3) and ANK61 antigen (ANK61) had no effect on pit cell-mediated CC531s or YAC-1 target cytolysis or apoptosis, while they did increase the Fcγ receptor positive (FcγR+) P815 cytolysis and apoptosis. This enhanced cytotoxicity could he inhibited by 3,4-dichloroisocoumarin, an inhibitor of granzymes. CONCLUSION These results indicate that CD45 participates in pit cell-mediated CC531s and YAC-1 target cytolysis and apoptosis. NKR-P1A and ANK61 antigen on pit cells function as activation structures against FcγR+ P815 cells, which was mediated by the perforin/granzyme pathway.     

Sex differences in knee cartilage volume in adults: role of body and bone size,age and physical activity

OBJECTIVE: To test the hypothesis that sex differences in knee cartilage volume may be mediated through body and bone size, age and/or physical activity. METHODS: A cross-sectional convenience sample of 372 subjects (males 43%; mean age 45 yr, range 26-61) was studied. Articular cartilage volumes and bone size were determined at the patella, medial and lateral tibia by processing images acquired in the sagittal plane using T1-weighted fat saturation magnetic resonance imaging. Height, weight, physical activity (lower limb muscle strength, endurance fitness and questionnaire items) and radiographic osteoarthritis (ROA) were measured. RESULTS: Gender explained 33-42% of the variation in knee cartilage volumes (all P < 0.001). Males had 33-42% higher cartilage volume than females at all sites. In the whole group, the magnitude of sex differences decreased to 8-18% after adjustment for body height, weight and bone size, but remained significant (all P < 0.05). Further adjustment for physical activity had no effect on the sex differences. The sex differences in cartilage volume were greater in those aged over 50 compared with those aged under 50 (P < 0.05 for age-sex interaction at all sites) and were independent of ROA. CONCLUSIONS: Men have substantially higher knee cartilage volumes than women. These sex differences appear to be mediated in part by body and bone size but a significant amount remains unexplained. Furthermore, the differences become more marked over the age of 50 yr suggesting that both cartilage development and cartilage loss in later life contribute to sex differences in cartilage volume. Further longitudinal studies in large samples will be required to confirm these findings.     

A method for simultaneous study of the karyotype, morphology, and immunologic phenotype of mitotic cells in hematologic malignancies

A major problem in the cytogenetic analysis of hematologic neoplasms has been an inability to identify the cell from which the chromosomes were obtained. We describe a procedure that allows simultaneous analysis of karyotype and cell cytology in mitotic cells. The method differs from conventional cytogenetic analysis in that after mild hypotonic treatment, the cells are cytocentrifuged onto glass slides. In mitotic cells, this procedure often results in adequate spread of the chromosomes within the intact cell membrane. The cytoplasmic structure also remains intact, so that cytologic preparations are of good quality. Morphologic and immunologic identification of mitotic cells can be done using routine hematologic stains, such as Giemsa or Sudan black B, and various antisera using immunofluorescence techniques. The chromosomes can be simultaneously analyzed either without banding on slides stained with Giemsa or with Q-banding on slides stained with immunofluorescence techniques. Identification of numerical and structural karyotype aberrations thus is possible in morphologically identified cells.