Comprehensive genetic and functional characterization of IPH-926: a novel CDH1-null tumour cell line from human lobular breast cancer.

Infiltrating lobular breast cancer (ILBC) is a clinically and biologically distinct tumour entity defined by a characteristic linear cord invasion pattern and inactivation of the CDH1 tumour suppressor gene encoding for E-cadherin. ILBCs also lack beta-catenin expression and show aberrant cytoplasmic localization of the E-cadherin binding protein p120-catenin. The lack of a well-characterized ILBC cell line has hampered the functional characterization of ILBC cells in vitro. We report the establishment of a permanent ILBC cell line, named IPH-926, which was derived from a patient with metastatic ILBC. The DNA fingerprint of IPH-926 verified genetic identity with the patient and had no match among the human cell line collections of several international biological resource banks. IPH-926 expressed various epithelial cell markers but lacked expression of E-cadherin due to a previously unreported, homozygous CDH1 241ins4 frameshift mutation. Detection of the same CDH1 241ins4 mutation in archival tumour tissue of the corresponding primary ILBC proved the clonal origin of IPH-926 from this particular tumour. IPH-926 also lacked beta-catenin expression and showed aberrant cytoplasmic localization of p120-catenin. Array-CGH analysis of IPH-926 revealed a profile of genomic imbalances that included many distinct alterations previously observed in primary ILBCs. Spectral karyotyping of IPH-926 showed a hyperdiploid chromosome complement and numerous clonal, structural aberrations. IPH-926 cells were anti-cancer drug-resistant, clonogenic in soft agar, and tumourigenic in SCID mice. In xenograft tumours, IPH-926 cells recapitulated the linear cord invasion pattern that defines ILBCs. In summary, IPH-926 significantly extends the biological spectrum of the established breast cancer cell lines and will facilitate functional analyses of genuine human ILBC cells in vitro and in vivo.

Erratum: Lazar-Karsten, P., et al. Generation and Characterization of Vascular Smooth Muscle Cell Lines Derived from a Patient with a Bicuspid Aortic Valve. Cells 2016, 5, 19.

The authors wish to make the following erratum to this paper [1].[...].

Generation and Characterization of Vascular Smooth Muscle Cell Lines Derived from a Patient with a Bicuspid Aortic Valve.

Thoracic aortic dilation is the most common malformation of the proximal aorta and is responsible for 1%-2% of all deaths in industrialized countries. In approximately 50% of patients with a bicuspid aortic valve (BAV), dilation of any or all segments of the aorta occurs. BAV patients with aortic dilation show an increased incidence of cultured vascular smooth muscle cell (VSMC) loss. In this study, VSMC, isolated from the ascending aorta of BAV, was treated with Simian virus 40 to generate a BAV-originated VSMC cell line. To exclude any genomic DNA or cross-contamination, highly polymorphic short tandem repeats of the cells were profiled. The cells were then characterized using flow cytometry and karyotyping. The WG-59 cell line created is the first reported VSMC cell line isolated from a BAV patient. Using an RT² Profiler PCR Array, genes within the TGFß/BMP family that are dependent on losartan treatment were identified. Endoglin was found to be among the regulated genes and was downregulated in WG-59 cells following treatment with different losartan concentrations, when compared to untreated WG-59 cells.

HMGA2 expression in the PC-3 prostate cancer cell line is autonomous of growth factor stimulation.

BACKGROUND: High-mobility group AT-hook 2 (HMGA2) protein acts as an oncofoetal transcriptional regulator. In mesenchymal tissues, its expression can be induced by a variety of growth factors such as fibroblast growth factor-1 (FGF1) and platelet-derived growth factor-BB (PDGF-BB) as well as by foetal bovine serum (FBS), thus enhancing proliferation. MATERIALS AND METHODS: To examine these effects in epithelial malignancies, we used the PC-3 prostate cancer cell line for assaying proliferation and HMGA2 expression in response to incubation with growth factors and FBS. The HMGA2 locus was investigated by fluorescence in situ hybridisation (FISH) for loss, amplification or re-arrangement. RESULTS: PC-3 is a cell line that moderately overexpresses HMGA2. None of the growth factors nor FBS caused significantly increased expression of HMGA2. In contrast, a significantly augmented proliferation rate was observed when applying FGF1 or PDGF-BB for 12 h. CONCLUSION: HMGA2 is expressed independently of external stimuli, whereas proliferation stimulated by growth factors is independent of further elevated HMGA2 expression.

MicroRNA miR-548d is a superior regulator in pancreatic cancer.

OBJECTIVES: This study aimed to identify microRNAs as novel biomarkers for improved diagnosis, prognosis prediction, and as a therapeutic target for pancreatic cancer. microRNAs may have a general role by acting as superordinated key regulators of tumorigenesis. METHODS: Individual cellular molecules of multiple pathways associated with pancreatic cancer were analyzed for common microRNA binding sites, thereby enabling the identification of key regulating microRNAs. The potential of the identified microRNAs was subsequently determined in cell culture experiments. RESULTS: Using bioinformatic pathway analyses, miR-548d was identified to target multiple components of pancreatic cancer-related pathways. The effect of microRNA on pancreatic cells was determined by overexpression studies using PANC-1 cells, resulting in impaired cell proliferation because of increased apoptosis and cell cycle arrest. In addition, miR-548d overexpression led to a sensitization to gemcitabine. CONCLUSIONS: MicroRNA miR-548d was identified as a potential superior regulator for the development and progression of pancreatic cancer by targeting multiple factors of crucial pathways. Therapeutically, microRNAs with superordinate function, such as miR-548d, may be promising diagnostic and therapeutic tools for the future treatment of pancreatic cancer.

Analysis of array-CGH data using the R and Bioconductor software suite.

BACKGROUND: Array-based comparative genomic hybridization (array-CGH) is an emerging high-resolution and high-throughput molecular genetic technique that allows genome-wide screening for chromosome alterations. DNA copy number alterations (CNAs) are a hallmark of somatic mutations in tumor genomes and congenital abnormalities that lead to diseases such as mental retardation. However, accurate identification of amplified or deleted regions requires a sequence of different computational analysis steps of the microarray data. RESULTS: We have developed a user-friendly and versatile tool for the normalization, visualization, breakpoint detection, and comparative analysis of array-CGH data which allows the accurate and sensitive detection of CNAs. CONCLUSION: The implemented option for the determination of minimal altered regions (MARs) from a series of tumor samples is a step forward in the identification of new tumor suppressor genes or oncogenes.