Topotecan plus ifosfamide in patients with platinum refractory advanced/metastatic non-small cell lung cancer: a phase II trial.

A number of second line treatments have been proposed in patients with advanced pretreated non-small cell lung cancer (NSCLC). However, either single agents or two or three drug combinations achieved very poor results with no superiority of any combination over monotherapy. We have treated 42 patients (30 males) affected by advanced/metastatic NSCLC progressing during front line cisplatin-based chemotherapy with a combination of topotecan (1.2 mg/m2) plus ifosfamide (1200 mg/m2) for 3 consecutive days every 3 weeks. The median age was 63 years (range 43-76); cell types were: squamous carcinoma (n=17), adenocarcinoma (n=16), large cell carcinoma (n=3), broncho-alveolar carcinoma (n=2) and undifferentiated carcinoma (n=4). All patients were treated with a platinum containing chemotherapy: 39 patients with cisplatin, 2 patients with carboplatin and 1 patient with oxaliplatin, respectively. The ECOG PS was 0 in 8 patients (19%), 1 in 11 patients (26%), and 2 in 23 patients (55%). The median number of courses administered was 3 (range 1-8). Grade 3-4 neutropenia was the dose limiting toxicity, observed in 36% of patients. Moreover, grade 3-4 anemia and thrombocytopenia were observed in 17% and in 12% of patients, respectively. One PS 2 patient died of grade 4 hematological toxicity after the first cycle. No complete response was observed. Six (14.2%) subjects obtained a partial response (PR). In addition, 1 (2.4%) minimal response (MR) plus 14 (34%) stable diseases (SD) and 21 (51%) progressive diseases (PD) were observed. Median time to disease progression and median survival were 9 weeks (range 1-13) and 26 weeks (range 1-91+), respectively. The 1-year survival rate was 14%. Combination of topotecan and ifosfamide demonstrated antitumor activity in patients with relapsing or refractory NCSLC with a modest side effect profile and an overall disease control (PR + MR + SD) of 50.7%. Nevertheless, the still low response rate and the shortness of median survival indicates the need for more effective second line treatments in this disease.

Ontogeny, distribution, and possible functional implications of an unusual aquaporin, AQP8, in mouse liver.

Aquaporins are channel proteins widely expressed in nature and known to facilitate the rapid movement of water across numerous cell membranes. A mammalian aquaporin, AQP8, was recently discovered and found to have a very distinct evolutionary pathway. To understand the reason for this divergence, here we define the ontogeny and exact subcellular localization of AQP8 in mouse liver, a representative organ transporting large volumes of water for secretion of bile. Northern blotting showed strong AQP8 expression between fetal day 17 and birth as well as at weaning and thereafter. Interestingly, this pattern was confirmed by immunohistochemistry and coincided both temporally and spatially with that of hepatic glycogen accumulation. As seen by reverse-transcription polymerase chain reaction (RT-PCR) and immunohistochemistry, fasting was accompanied by remarkable down-regulation of hepatic AQP8 that paralleled the expected depletion of glycogen content. The level of hepatic AQP8 returned to be considerable after refeeding. Immunoelectron microscopy confirmed AQP8 in hepatocytes where labeling was over smooth endoplasmic reticulum (SER) membranes adjacent to glycogen granules and in canalicular membranes, subapical vesicles, and some mitochondria. In conclusion, in addition to supporting a role for AQP8 in canalicular water secretion, these findings also suggest an intracellular involvement of AQP8 in preserving cytoplasmic osmolality during glycogen metabolism and in maintaining mitochondrial volume. AQP8 may have evolved separately to feature these intracellular roles as no other known aquaporin shows this specialization.