Dose-volumetric parameters and prediction of severe acute esophagitis in patients with locally-advanced non small-cell lung cancer treated with neoadjuvant concurrent hyperfractionated-accelerated chemoradiotherapy

Background: To identify dose-volume parameters predictive for severity of acute esophagitis (CTC > grade 2) in locally-advanced non small-cell lung cancer (LA-NSCLC) patients treated with neoadjuvant concurrent hyperfractionated-accelerated chemoradiotherapy (HA-CRT) a retrospective analysis was performed. 88 patients were treated with HA-CRT followed by radical surgery. Predictive power of absolute oesophageal length, absolute and relative oesophageal volume included in the 95\%-isodose, patient-and tumor-related factors for severity of acute esophagitis was assessed. Findings: A total of 82 patients (93\%) developed radiation-induced acute esophagitis. Grade 1 was documented in 1 (1\%), grade 2 in 55 (67\%), grade 3 in 23 (28\%) and grade 4 in 3 (4\%) patients, respectively. Absolute oesophageal volume included in the 95\%-isodose (42.8 Gy) achieved 13.5 cm(3) (range: 3 - 29 cm(3)). Of the tested variables in univariate analysis, absolute oesophageal volume included in the 95\%-Isodose was found to be the only significant variable (p = 0.03) predicting severe acute esophagitis (CTC > grade 2). For this volume a gradation scale of the likelihood of severity was built. Conclusion: Increase of absolute oesophageal volume included in the 95\%-isodose correlates with severity of acute esophagitis in LA-NSCLC patients treated with neo-adjuvant concurrent HA-CRT

Dasatinib reverses Cancer-associated Fibroblasts (CAFs) from primary Lung Carcinomas to a Phenotype comparable to that of normal Fibroblasts

Cancer associated fibroblasts (CAFs) play a critical role for growth, invasion, and metastasis of cancer. Therefore, targeting CAFs with small molecule inhibitors may be an attractive anti-tumor strategy. The current study aims to identify small molecule kinase inhibitors affecting CAF's growth and to characterize the biological effects of active compounds on primary CAFs from lung cancer. We screened two individual CAF strains for their sensitivity to a panel of 160 kinase inhibitors. Five kinase inhibitors were identified inhibiting more than 50% of the growth of both cell lines. Three of them were inhibitors of PDGFR at nanomolar concentrations. Therefore, we further tested the FDA approved PDGFR inhibitors Dasatinib, Nilotinib, Sorafenib, and Imatinib. All 37 CAF strains investigated were highly sensitive to Dasatinib at clinically relevant concentrations. Imatinib was slightly less effective, whereas the inhibitory effects of Nilotinib and Sorafenib were significantly less pronounced

Highly variable response to cytotoxic chemotherapy in carcinoma-associated fibroblasts (CAFs) from lung and breast

<p>Abstract</p> <p>Background</p> <p>Carcinoma-associated fibroblasts (CAFs) can promote carcinogenesis and tumor progression. Only limited data on the response of CAFs to chemotherapy and their potential impact on therapy outcome are available. This study was undertaken to analyze the influence of chemotherapy on carcinoma-associated fibroblasts (CAFs) <it>in vitro </it>and <it>in vivo</it>.</p> <p>Methods</p> <p>The <it>in vivo </it>response of stromal cells to chemotherapy was investigated in 22 neoadjuvant treated breast tumors on tissue sections before and after chemotherapy. Response to chemotherapy was analyzed <it>in vitro </it>in primary cultures of isolated CAFs from 28 human lung and 9 breast cancer tissues. The response was correlated to <it>Mdm2</it>, <it>ERCC1 </it>and <it>TP53 </it>polymorphisms and <it>TP53 </it>mutation status. Additionally, the cytotoxic effects were evaluated in an <it>ex vivo </it>experiment using cultured tissue slices from 16 lung and 17 breast cancer specimens.</p> <p>Results</p> <p>Nine of 22 tumors showed a therapy-dependent reduction of stromal activity. Pathological response of tumor or stroma cells did not correlate with clinical response. Isolated CAFs showed little sensitivity to paclitaxel. In contrast, sensitivity of CAFs to cisplatinum was highly variable with a GI50 ranging from 2.8 to 29.0 μM which is comparable to the range observed in tumor cell lines. No somatic <it>TP53 </it>mutation was detected in any of the 28 CAFs from lung cancer tissue. In addition, response to cisplatinum was not significantly associated with the genotype of <it>TP53 </it>nor <it>Mdm2 </it>and <it>ERCC1 </it>polymorphisms. However, we observed a non-significant trend towards decreased sensitivity in the presence of <it>TP53 </it>variant genotype. In contrast to the results obtained in isolated cell culture, in tissue slice culture breast cancer CAFs responded to paclitaxel within their microenvironment in the majority of cases (9/14). The opposite was observed in lung cancer tissues: only few CAFs were sensitive to cisplatinum within their microenvironment (2/15) whereas a higher proportion responded to cisplatinum in isolated culture.</p> <p>Conclusion</p> <p>Similar to cancer cells, CAF response to chemotherapy is highly variable. Beside significant individual/intrinsic differences the sensitivity of CAFs seems to depend also on the cancer type as well as the microenvironment.</p