Caroline Hammer

Possible role of Cdx2 in the serrated pathway of colorectal cancer characterized by BRAF mutation, high-level CpG Island methylator phenotype and mismatch repair-deficiency.

Colorectal cancer is a heterogeneous disease at the histomorphological, clinical and molecular level. Approximately 20% of cases may progress through the “serrated” pathway characterized by BRAF mutation and high‐level CpG Island Methylator Phenotype (CIMP). A large subgroup are additionally microsatellite instable (MSI) and demonstrate significant loss of tumor suppressor Cdx2. The aim of this study is to determine the specificity of Cdx2 protein expression and CpG promoter hypermethylation for BRAFV600E and high‐level CIMP in colorectal cancer. Cdx2, Mlh1, Msh2, Msh6, and Pms2 were analyzed by immunohistochemistry using a multi‐punch tissue microarray (TMA; n = 220 patients). KRAS and BRAFV600E mutation analysis, CDX2 methylation and CIMP were investigated. Loss of Cdx2 was correlated with larger tumor size (P = 0.0154), right‐sided location (P = 0.0014), higher tumor grade (P < 0.0001), more advanced pT (P = 0.0234) and lymphatic invasion (P = 0.0351). Specificity was 100% for mismatch repair (MMR)‐deficiency (P < 0.0001), 92.2% (P < 0.0001) for BRAFV600E and 91.8% for CIMP‐high. Combined analysis of BRAFV600E/CIMP identified Cdx2 loss as sensitive (80%) and specific (91.5%) for mutation/high status. These results were validated on eight well‐established colorectal cancer cell lines. CDX2 methylation correlated with BRAFV600E (P = 0.0184) and with Cdx2 protein loss (P = 0.0028). These results seem to indicate that Cdx2 may play a role in the serrated pathway to colorectal cancer as underlined by strong relationships with BRAFV600E, CIMP‐high and MMR‐deficiency. Whether this protein can only be used as a “surrogate” marker, or is functionally involved in the progression of these tumors remains to be elucidated.

Effects on hepatocellular carcinoma of doxorubicin-loaded immunoliposomes designed to target the VEGFR-2

To maintain a tumour vasculature in proportion of the tumour growth, the endothelial cells proliferate and up-regulate the expression of the VEGF receptor 2 (VEGFR-2), whose expression is restricted to this cell type. This specificity implies that one therapeutically target the tumour endothelium. We investigated the use of immunoliposomes (IL), containing conjugated Fab′ fragments of the monoclonal rat anti-VEGFR-2 antibody DC101 (DC101-IL) to cargo doxorubicin to the tumour endothelium. In vitro, fluorescein-labelled IL displayed a 7 fold better binding to VEGFR-2-positive 293T cells in comparison to unspecific liposomes. Balb/C mice were injected subcutaneously with syngeneic hepatocellular carcinoma cells. One set of animals was treated with DC101-IL filled with doxorubicin when the tumours were bigger than 400 mm3. A specific delivery of doxorubicin to endothelial cells of the tumour vessels could be demonstrated by the red fluorescence of doxorubicin with laser scanning microscopy, but neither a delay of tumour growth nor a shrinking of the tumour mass was observed. Yet necrosis in the tumours treated with doxorubicin containing vehicles was larger than in the tumours of the control groups. A second set of animals was treated with DC101-IL filled with doxorubicin when the tumours were smaller than 1 mm3. DC101-IL filled with doxorubicin led to a significant delay in tumour growth up to 7 weeks compared to empty DC101-IL, free doxorubicin, and HEPES/Glucose (HEPES/Glucose vs. DOX-DC101-IL, p = 0.001; unpaired, two-tailed Students t-test) and to a higher amount of necrotic areas in the tumours (p = 0.053; 1 way ANOVA with 4 groups). These findings suggest that IL designed to bind specifically to VEGFR-2 can be used to deliver doxorubicin to the tumour endothelium and may impair the “angiogenic switch” of the tumours.

The apoptotic and proliferation rate of tumour budding cells in colorectal cancer outlines a heterogeneous population of cells with various impacts on clinical outcome.

In colorectal cancer (CRC), tumour buds represent an aggressive cell type at the invasive front with apparently low proliferation. The aim of this study was to determine proliferation and apoptotic rates of buds in comparison to tumour centre, front and mucosa.

Proper paraffin slide storage is crucial for translational research projects involving immunohistochemistry stains

The use of paraffin slides and tissue microarrays (TMA) is indispensable for translational research. However, storage of paraffin slides over time has a substantial detrimental effect on the quality and reliability of immunohistochemistry stains. Particularly affected by this issue may be any collaborative efforts where paraffin slides or TMAs are shipped to central laboratories and then ‘biobanked’ for some time until use. This article summarizes some of the key issues affecting loss of antigenicity on paraffin slides and some simple storage solutions to help maintain high quality immunohistochemistry results when paraffin slides must be stored for a certain time prior to use.

The homeobox gene HLXB9 is upregulated in a morphological subset of poorly differentiated hepatocellular carcinoma

The prognostic outcome for hepatocellular carcinoma (HCC) remains poor. Disease progression is accompanied by dedifferentiation of the carcinoma, a process that is not well understood. The aim of this study was to get more insight into the molecular characteristics of dedifferentiated carcinomas using high throughput techniques. Microarray-based global gene expression analysis was performed on five poorly differentiated HCC cell lines compared with non-neoplastic hepatic controls and a set of three cholangiolar carcinoma (CC) cell lines. The gene with the highest upregulation was HLXB9. HLXB9 is a gene of the homeobox genfamily important for the development of the pancreas. RT-PCR confirmed the upregulation of HLXB9 in surgical specimens of carcinoma tissue, suggesting its biological significance. Interestingly, HLXB9 upregulation was primary observed in poorly differentiated HCC with a pseudoglandular pattern compared with a solid pattern HCC or in moderate or well-differentiated HCC. Additional the expression of translated HLXB9, the protein HB9 (NCBI: NP_001158727), was analyzed by western blotting. Expression of HB9 was only detected in the cytoplasm but not in the nuclei of the HCC cells. For validation CC were also investigated. Again, we found an upregulation of HLXB9 in CC cells accompanied by an expression of HB9 in the cytoplasms of these tumor cells, respectively. In conclusion, homeobox HLXB9 is upregulated in poorly differentiated HCC with a pseudoglandular pattern. The translated HB9 protein is found in the cytoplasm of these HCC and CC. We therefore assume HLXB9 as a possible link in the understanding of the development of HCC and CC, respectively.

Drug targeting using OX7-immunoliposomes: Correlation between Thy1.1 antigen expression and tissue distribution in the rat

OX7 monoclonal antibody F(ab′)2 fragments directed against Thy1.1 antigen can be used for drug targeting by coupling to the surface of drug-loaded liposomes. Such OX7-conjugated immunoliposomes (OX7-IL) were used recently for drug delivery to rat glomerular mesangial cells, which are characterized by a high level of Thy1.1 antigen expression. In the present study, the relationship between OX7-IL tissue distribution and target Thy1.1 antigen localization in different organs in rat was investigated. Western blot and immunohistofluorescence analysis revealed a very high Thy1.1 expression in brain cortex and striatum, thymus and renal glomeruli. Moderate Thy1.1 levels were observed in the collecting ducts of kidney, lung tissue and spleen. Thy1.1 was not detected in liver and heart. There was a poor correlation between Thy1.1 expression levels and organ distribution of fluorescence- or 14C-labeled OX7-IL. The highest overall organ density of OX7-IL was observed in the spleen, followed by lung, liver and kidney. Heart and brain remained negative. With respect to intra-organ distribution, a localized and distinct signal was observed in renal glomerular mesangial cells only. As a consequence, acute pharmacological (i.e. toxic) effects of doxorubicin-loaded OX7-IL were limited to renal glomeruli. The competition with unbound OX7 monoclonal antibody F(ab′)2 fragments demonstrated that the observed tissue distribution and acute pharmacological effects of OX7-IL were mediated specifically by the conjugated OX7 antibody. It is concluded that both the high target antigen density and the absence of endothelial barriers are needed to allow for tissue-specific accumulation and pharmacological effects of OX7-IL. The liposomal drug delivery strategy used is therefore specific toward renal glomeruli and can be expected to reduce the risk of unwanted side effects in other tissues.

Hepatocellular and cholangiolar carcinoma-derived cell lines reveal distinct sets of chromosomal imbalances.

Objectives: Hepatocellular carcinoma (HCC) and cholangiolar carcinoma (CC) cell lines are used to analyze the basic mechanisms of carcinogenesis and target therapies. However, it is not yet clear which chromosomal aberrations are to be typically expected in such cell lines. It is also not clear whether there are prerequisites for in vitro growth on the genomic and/or expression level. We therefore analyzed HCC and CC cell lines for typical genetic settings. Methods: The HCC cell lines HLE, HLF, Huh7, HepG2 and Hep3b and the CC cell lines EGI1, MzCha1 and TFK-1 were analyzed using high-density arrays for comparative genomic hybridization (aCGH; 244,000 oligonucleotides). Additional fluorescence in situ hybridization analyses were done to confirm the aCGH results and to add information regarding the aneuploidy of cell lines. Results: The gain of 1q, in particular q21-22, was detected in all HCC cell lines also as a partial loss of 13q. In contrast, a loss of 8p in combination with a relative gain of 8q was seen in all CC but no HCC cell lines. Interestingly, a gain of 17q was seen in all cell lines. These aberrations are also well documented for surgical tumor specimens. Besides these imbalances, the cell lines revealed imbalances for 11p, 12p, 14q, 16p, 16q, 21q and 22q, respectively, only rarely seen in surgical tumor specimens. These aberrations could be of importance for the in vitro cultivation of tumor cells. Structural aberrations were accompanied by aneuploidy in 3 of 5 HCC cell lines and 2 of 3 CC cell lines. Ploidy status was not correlated to any of the imbalances mentioned above. Conclusions: HCC and CC cell lines revealed characteristic chromosomal imbalances similar to those seen in surgical tumor specimens including chromosomes 1, 8, 13 and 17, respectively. These aberrations are characteristic of the histogenetic origin of the tumor cells. However, the chromosomal imbalances that occurred probably led to the ability of tumor cells to grow in vitro.

Lean-Management im Pathologielabor

Der zunehmende Zeitund Effizienzdruck im Gesundheitswesenmacht auch vor der Pathologie nicht halt. Zusätzlich unterliegt der Beruf des Pathologen durch die äußeren Faktoren Automatisierung, Digitalisierung, Molekularbiologie undpersonalisierteMedizin, die auf den ersten Blick als eine Art „apokalyptische Reiter“ verstanden werden könnten, einem zunehmenden Entwicklungsund Definitionsdruck. Universitäre Institutionen sind zusätzlich durch die Zusatzaufgaben von Ausbildung und Forschung gefordert. Um sich diesen Herausforderungen zu stellen, gibt es viele zielführendeWege.DasPrinzipdesLeanManagements ist einer davon. Die Anwendung des Lean-Konzepts auf Arbeitsprozesse in der klinischen Pathologie zur Standardisierung, Fehlerreduktion und Minimierung von Verschwendung ist nach wie vor nicht weit verbreitet. Obwohl Patientenproben keine Karosseriebauteile sind, lässt sich derenAufarbeitung in vielenFällen so standardisieren und optimieren, dass das eigentliche Kernstück, die Diagnostik, relativ gesehen mehr zeitlichen Raum einnehmen kann, bei gleichzeitiger Verkürzung der Durchlaufzeit. Folgende Dinge gilt es vor Beschreitung des Lean-Pfades zu beachten: Das Ziel muss klar definiert sein, „Navigationstools“ zur Kursüberprüfung und ggf. Kursanpassung und ein Team, dass die UmsetzungvonLeanunterstützt,müssen vorhanden sein [4]. Eigenverantwortung

Lean management in the pathology laboratory

Der zunehmende Zeitund Effizienzdruck im Gesundheitswesenmacht auch vor der Pathologie nicht halt. Zusätzlich unterliegt der Beruf des Pathologen durch die äußeren Faktoren Automatisierung, Digitalisierung, Molekularbiologie undpersonalisierteMedizin, die auf den ersten Blick als eine Art „apokalyptische Reiter“ verstanden werden könnten, einem zunehmenden Entwicklungsund Definitionsdruck. Universitäre Institutionen sind zusätzlich durch die Zusatzaufgaben von Ausbildung und Forschung gefordert. Um sich diesen Herausforderungen zu stellen, gibt es viele zielführendeWege.DasPrinzipdesLeanManagements ist einer davon. Die Anwendung des Lean-Konzepts auf Arbeitsprozesse in der klinischen Pathologie zur Standardisierung, Fehlerreduktion und Minimierung von Verschwendung ist nach wie vor nicht weit verbreitet. Obwohl Patientenproben keine Karosseriebauteile sind, lässt sich derenAufarbeitung in vielenFällen so standardisieren und optimieren, dass das eigentliche Kernstück, die Diagnostik, relativ gesehen mehr zeitlichen Raum einnehmen kann, bei gleichzeitiger Verkürzung der Durchlaufzeit. Folgende Dinge gilt es vor Beschreitung des Lean-Pfades zu beachten: Das Ziel muss klar definiert sein, „Navigationstools“ zur Kursüberprüfung und ggf. Kursanpassung und ein Team, dass die UmsetzungvonLeanunterstützt,müssen vorhanden sein [4]. Eigenverantwortung

Implementation of a ‘lean’ cytopathology service: towards routine same-day reporting

Objectives To systematically assess the effects of a Lean management intervention in an academic cytopathology service. Methods We monitored outcomes including specimen turnaround times during stepwise implementation of a lean cytopathology workflow for gynaecological and non-gynaecological cytology. Results The intervention resulted in a major reduction of turnaround times for both gynaecological (3rd quartile 4.1 vs 2.3 working days) and non-gynaecological cytology (3rd quartile 1.9 vs. 1.2 working days). Introduction of fully electronic reporting had additional effect over continuous staining of slides alone. The rate of non-gynaecological specimens reported the same day increased from 4.5% to 56.5% of specimens received before noon. Conclusions Lean management principles provide a useful framework for organization of a cytopathology workflow. Stepwise implementation beginning with a simplified gynaecological cytology workflow allowed involved staff to monitor the effects of individual changes and allowed for a smooth transition.