RESUMO
Lung cancer remains the leading cause of cancer death throughout the world. Despite new chemotherapeutic, immunomodulating and molecularly targeted agents, patients with locally advanced or metastatic disease still have a poor prognosis. This trial looked to combine antiangiogenic therapy with a first-line cytotoxic chemotherapy doublet, hoping to extend median progression-free survival (PFS) while minimizing toxicity in patients with advanced nonsquamous non-small-cell lung cancer (NSCLC). In this single institution, single-arm study, 51 patients (age >18 yo) were followed from 2007 to 2012. Patients with stage IV nonsquamous NSCLC and patients with recurrent unresectable disease (nonradiation candidates) were eligible. Treatment consisted of carboplatin AUC 5 IV 30-60 minutes, pemetrexed 500/mg2 IV 10 minutes, bevacizumab 15 mg/kg IV (90 minutes 1st dose, 60 minutes 2nd dose, 30 minutes subsequent doses). Treatment was administered every 21 days and planned for 6 cycles, in the absence of disease progression or unacceptable toxicities. Growth factor support was not permitted prophylactically but allowed for toxicities, as were dose reductions. Maintenance treatment for those with stable disease or better consisted of Bevacizumab 15 mg/kg every 3 weeks for up to 1 year. Between November 2007 and March 2012, 51 patients were followed in the phase II trial of carboplatin, pemetrexed, and bevacizumab. Patients were enrolled over a 24-month period. After the end of treatment visits, subjects were followed at least every 3 months for survival data. The median follow-up period was 49 weeks (6 weeks to 178), and the median number of treatment cycles was 6 (range, 1-6). Among the 50 patients assessable for response, median overall survival was 49 weeks (95% CI, 0-62.7) with median PFS of 28 weeks (95% CI, 0-132.4). A complete or partial response was seen in 28 (59.5%) patients. Grade 3-4 treatment-related adverse events occurred in 9 (17.6%) of 51 patients; the most common were thrombocytopenia (4 [7.8%]) and neutropenia (3 [5.9%]). Three (5.8%) of 51 patients were discontinued because of treatment-related adverse events (grade 3 diarrhea, thrombocytopenia, dehydration, fatigue, and grade 4 respiratory distress), and 1 patient (1.9%) was found to be ineligible due to anticoagulation use. A novel 3-drug combination for advanced nonsquamous NSCLC shows promising efficacy with modest toxicity.
RESUMO
BACKGROUND: Agnogenic myeloid metaplasia (AMM) is one of the Philadelphia chromosome negative myeloproliferative disorder and is diagnosed by hyperplasia of atypical megakaryocytes, hepatosplenomegaly, extramedullary hematopoiesis and bone marrow fibrosis. Fibrosis is considered to be a secondary consequence of enhanced levels of fibrogenic growth factors such as TGF beta1, bFGF and PDGF produced by enhanced numbers of megakaryocytes, while the primary cause is considered to be the enhanced proliferation of a defective stem cell. We have previously reported that thrombopoietin (TPO) is elevated in patients with AMM. Others have reported that Mpl protein is decreased in these patients. Since TPO is essential for the development of megakaryocytes, and Mpl protein is the receptor for TPO, we extended the study of TPO/Mpl to in vitro and in vivo cell culture systems to better understand the mechanism that leads to reduced Mpl protein in AMM patients. RESULTS: Plasma TPO levels were significantly elevated and Mpl protein levels were significantly reduced in AMM patients in concordance with previous studies. Platelet Mpl transcripts in AMM were however similar to those in controls. We also cloned Mpl cDNA from AMM patients and tested for their ability to make functional proteins in vitro and in the in vivo system of 293 T human embryonic kidney cells. Their expression including the glycosylated forms was similar to those from the controls. We also measured the level of translation initiation factor, eIF4E and found it to be increased in patients with AMM demonstrating that the reduced Mpl protein may not be due to translation defects. CONCLUSIONS: Our studies using the in vitro and in vivo systems further confirm that reduced Mpl protein levels are not due to defects in its transcription/translation. Reduced Mpl protein could be due to its increased internalisation owing to enhanced plasma TPO or in vivo intrinsic defects in patients with AMM.
