Growth rate and myofibroblast differentiation of desmoid fibroblast-like cells are modulated by TGF-ß signaling.

Desmoid-like fibromatosis (DF) is a rare myofibroblastic benign tumor, often associated with local and repeated injuries, spontaneous regression and stabilization of disease progression suggesting the involvement of altered Wnt/ß-catenin signaling activation and/or aberrant response of the DF cells to external environmental stimuli. The aim of this study was to investigate the response of DF cells to microenvironmental factors such as inflammatory and growth factors or hormones. We observed that the inflammatory cytokine, transforming growth factor-ß (TGF-ß1) stimulated cell growth and myofibroblast differentiation of DF cells regardless of the presence of a ß-catenin mutation. The role of TGF-ß1 in cell growth and myogenic differentiation of in vitro cultures of primary DF cells and normal fibroblasts was investigated by gene and protein expression analyses. We demonstrated that TGF-ß1 exerted its role via the canonical Smad pathway with the phosphorylation of Smad3 being crucial for TGF-ß1 dependent DF cell growth and myofibroblastic differentiation. Furthermore we demonstrated that cell confluence is a critical determinant of TGF-ß1 inducing the DF myofibroblast differentiation, implying that the intercellular communications have an important role on the DF myofibroblast behavior. We observed the formation of an increased stress-fiber pattern in DF cells with increased projected cell area and stronger cell-cell contacts in presence of TGF-ß1. These results demonstrated that TGF-ß1 plays a crucial role in the DF cells growth and, together with cell-cell interactions, in DF myofibroblast conversion; we also highlighted that the cellular sensitivity to this cytokine was an intrinsic feature of the DF cells.

T([20]) repeat in the 3'-untranslated region of the MT1X gene: a marker with high sensitivity and specificity to detect microsatellite instability in colorectal cancer.

PURPOSE: Stratifying patients defective in mismatch repair (dMMR) with high microsatellite instability (MSI-H) in colorectal cancer (CRC) is of increasing relevance and may provide a more tailored approach to CRC adjuvant therapy. Here, we describe the discovery of a new MSI marker for colorectal cancer located in the 3'-untranslated region (3'UTR, T20 mononucleotide repeat) of the metallothionein 1X gene (MT1XT20). METHODS: We studied 340 consecutive CRCs using three multiplexed polymerase chain reactions amplifying BAT25, BAT26, TGFBR2, MybT22, BAT40, MT1XT20, NR21, NR24, CAT25, D2S123, D5S346, D17S250, D18S58, CSF1PO, D7S820, and D18S51. Fragments length was evaluated by automated capillary electrophoresis. RESULTS: Based on the NCI/ICG-HNPCC criteria for MSI classification, 40 CRCs were found to be MSI-high (11.8%), 46 (13.5%) CRCs were MSI-low, and 254 CRCs (74.7%) were stable (MSS). MT1XT20 showed very high sensitivity (97.3%) comparable to BAT26 (97.5%) and CAT25 (97.1%) and the best specificity (100%) as well as MybT22 and CAT25. Indeed, MT1XT20 instability was detected in 36 out of 37 cases (97.3%) of MSI-high colorectal cancers, whereas no MT1XT20 alterations were observed in 254 MSS or in 46 MSI-low cases. On the contrary, BAT40 was found to be unstable in 8/46 MSI-low cases, BAT25 in 6/46, BAT26 4/46, NR21 1/46, and NR24 in 1/45. CONCLUSIONS: Our results suggest that MT1XT20 represents a sensitive and specific marker for MSI testing and could be included in a complete set of MSI markers for the confident identification of familial or sporadic dMMR patients in CRCs.

Core needle biopsy of soft tissue tumors, CEUS vs US guided: a pilot study.

PURPOSE: The purpose of this study was to evaluate the usefulness of contrast-enhanced ultrasonography (CEUS) in the bioptic sampling of soft tissue tumors (STT) compared with unenhanced ultrasonography alone. METHODS: This is a prospective longitudinal study of 40 patients subjected to ultrasonography (US)-guided core needle biopsy (CNB) to characterize a suspected STT. Three series of bioptic samplings were carried out on each patient, respectively using unenhanced US alone and CEUS in both the areas of the tumor enhanced or not by the contrast medium. All bioptic samples underwent a histological evaluation and the results were analyzed by comparing the histology of the biopsy with the definitive diagnosis in 15 surgically excised samples. RESULTS: 27 (67.5 %) of the 40 patients completed the entire study procedure; in 19 cases (70.3 %) the three bioptic samplings gave unanimous results, also when compared to the surgical specimen; in seven cases (25.9 %) use of CEUS allowed to obtain additional or more accurate information about the mass in question, compared to simple US guidance without contrast; in one patient (3.7 %) sampling obtained using unenhanced ultrasonography guidance and in the areas enhanced by the contrast agent had precisely the same results of the surgical specimen. CONCLUSIONS: CEUS, due to its ability to evaluate microvascular areas, has proven to be a promising method in guiding bioptic sampling of soft tissue tumor, directing the needle to the most significant areas of the tumor. Given the small number of patients evaluated in our study, to achieve statistically significant results, it would be appropriate to obtain a larger sample size, since the very first results seem to be encouraging and to justify the increase of the population.