ABSTRACT
BACKGROUND AND PURPOSE: Simultaneous targeting of ß1 integrin receptor and epidermal growth factor receptor (EGFR) showed higher level of radiosensitization in head and neck cancers than monotherapies. As EGFR inhibition is similarly performed in colorectal cancer (CRC), we investigated the radiosensitizing and anti-invasive potential of ß1-integrin/EGFR inhibition in CRC cell lines grown in more physiological three-dimensional (3D) matrix-based cell cultures. MATERIALS AND METHODS: DLD-1 and HT-29 cells were used for 3D-colony formation, invasion and proliferation assays and Western blotting. ß1 integrin, focal adhesion kinase and EGFR were inhibited by AIIB2, TAE226 and Cetuximab, respectively. KRAS and BRAF knockdown were accomplished using small-interfering RNA technology. Single doses of X-rays ranged from 2Gy to 6Gy and 5-fluorouracil (5-FU) concentration was 10µM. RESULTS: Neither ß1-integrin/EGFR inhibition nor KRAS or BRAF depletion nor 5-FU significantly modified CRC cell radiosensitivity. Cetuximab, AIIB2 and Cetuximab/AIIB2 differentially modulated MAPK, JNK and AKT phosphorylation. AIIB2 and TAE226 significantly decreased cell invasion. CONCLUSIONS: Our data show inefficiency of Cetuximab and AIIB2 on top of radiochemotherapy. The functions of KRAS and BRAF in therapy resistance remain unanswered and warrant further preclinical molecular-driven investigations. One promising approach might be ß1 integrin targeting for reducing metastatic CRC cell spread.
Subject(s)
Colorectal Neoplasms/radiotherapy , ErbB Receptors/antagonists & inhibitors , Integrin beta1/metabolism , Radiation-Sensitizing Agents/pharmacology , Antineoplastic Agents/pharmacology , Cell Line, Tumor , Cell Proliferation/drug effects , Cetuximab/pharmacology , Colorectal Neoplasms/pathology , Fluorouracil/pharmacology , Focal Adhesion Kinase 1/metabolism , Focal Adhesion Protein-Tyrosine Kinases/metabolism , HT29 Cells , Humans , Neoplasm Invasiveness , RNA, Small Interfering/pharmacology , Radiation Tolerance/drug effectsABSTRACT
Ripening-dependent changes of pineapple volatiles were studied in a nontargeted profiling analysis. Volatiles were isolated via headspace solid phase microextraction and analyzed by comprehensive 2D gas chromatography and mass spectrometry (HS-SPME-GC×GC-qMS). Profile patterns presented in the contour plots were evaluated applying image processing techniques and subsequent multivariate statistical data analysis. Statistical methods comprised unsupervised hierarchical cluster analysis (HCA) and principal component analysis (PCA) to classify the samples. Supervised partial least squares discriminant analysis (PLS-DA) and partial least squares (PLS) regression were applied to discriminate different ripening stages and describe the development of volatiles during postharvest storage, respectively. Hereby, substantial chemical markers allowing for class separation were revealed. The workflow permitted the rapid distinction between premature green-ripe pineapples and postharvest-ripened sea-freighted fruits. Volatile profiles of fully ripe air-freighted pineapples were similar to those of green-ripe fruits postharvest ripened for 6 days after simulated sea freight export, after PCA with only two principal components. However, PCA considering also the third principal component allowed differentiation between air-freighted fruits and the four progressing postharvest maturity stages of sea-freighted pineapples.
Subject(s)
Ananas/chemistry , Volatile Organic Compounds/chemistry , Ananas/growth & development , Ananas/metabolism , Discriminant Analysis , Fruit/chemistry , Fruit/growth & development , Fruit/metabolism , Gas Chromatography-Mass Spectrometry/instrumentation , Gas Chromatography-Mass Spectrometry/methods , Multivariate Analysis , Odorants/analysis , Principal Component Analysis , Volatile Organic Compounds/metabolismABSTRACT
Pericolonic tumor deposits (PTDs) are associated with an adverse outcome in colorectal cancer. According to the International Union Against Cancer they are classified as N1 or V1/V2 depending on their shape. This recommendation, however, is not well supported by the literature. To elucidate the origin of PTDs, we performed a histomorphologic study of 69 PTDs, which were found in 7 of 21 colorectal specimens using the whole-mount step-section technique. Depending on the origin, the nodules were classified as venous invasions, lymphatic invasions, nerve sheath infiltrations, free PTDs, and continuous growth in 18 (26%), 3 (4%), 6 (9%), 34 (49%), and 8 (12%) of 69 PTDs, respectively. Polycyclic and oval-round shapes were identified in all categories. Continuous growth was found only within the inner third of the adhering fat, whereas the other morphologic features were found in all regions. The data of this study do not support PTD classification on the basis of their shape.
