Andrea Hasenfus

Progranulin antibodies in autoimmune diseases

Systemic vasculitides constitute a heterogeneous group of diseases. Autoimmunity mediated by B lymphocytes and their humoral effector mechanisms play a major role in ANCA-associated vasculitis (AAV) as well as in non-ANCA associated primary systemic vasculitides and in the different types of autoimmune connective tissue disorders and rheumatoid arthritis. In order to detect autoantibodies in systemic vasculitides, we screened protein macroarrays of human cDNA expression libraries with sera from patients with ANCA-associated and ANCA-negative primary systemic vasculitides. This approach led to the identification of antibodies against progranulin, a 88 kDA secreted glycoprotein with strong anti-inflammatory activity in the course of disease of giant-cell arteritis/polymyalgia rheumatica (14/65), Takayasus arteritis (4/13), classical panarteritis nodosa (4/10), Behcets disease (2/6) and in the course of disease in granulomatosis with polyangiitis (31/75), Churg-Strauss syndrome (7/23) and in microscopic polyangiitis (7/19). In extended screenings the progranulin antibodies were also detected in other autoimmune diseases such as systemic lupus erythematosus (39/91) and rheumatoid arthritis (16/44). Progranulin antibodies were detected only in 1 of 97 healthy controls. Anti-progranulin positive patients with systemic vasculitides, systemic lupus erythematosus or rheumatoid arthritis had significant lower progranulin plasma levels, indicating a neutralizing effect. In light of the anti-inflammatory effects of progranulin, progranulin antibodies might exert pro-inflammatory effects thus contributing to the pathogenesis of the respective autoimmune diseases and might serve as a marker for disease activity. This hypothesis is supported by the fact that a positive progranulin antibody status was associated with active disease in granulomatosis with polyangiitis.

Silencing of the SEC62 gene inhibits migratory and invasive potential of various tumor cells

Sec62 is part of the protein translocation apparatus in the membrane of the endoplasmic reticulum (ER). In yeast, Sec62 participates in the post‐translational translocation of proteins into the ER, but its function in mammals remains elusive. Previously we described the amplification and over‐expression of the SEC62 gene in prostate cancer cell lines and the protein has been described as a potential target gene in prostate cancer. In the current study we show that in the tumor tissue of prostate cancer patients Sec62 protein levels are elevated compared with tumor‐free tissue derived from the same patients or from prostates of control group patients and that the higher Sec62 protein content correlates with an increasing de‐differentiation of the cells. Therefore, up‐regulation of Sec62 protein content indeed is a phenomenon associated with prostate cancer progression. Analysis of a multi‐tissue tumor array showed that in addition to prostate cancer, overproduction of Sec62 is observed in various other tumors, most significantly in tumors of the lung and the thyroid. To examine the tumor‐related functions of Sec62, we silenced the SEC62 gene in the prostate cancer cell‐line PC3 as well as in a set of other tumor cell‐lines with two different siRNAs. In general, after silencing of SEC62 the cell migration and the invasive potential of the cells was blocked or at least dramatically reduced while cell viability was hardly affected. Thus, the SEC62 gene may indeed be considered as a target gene in the therapy of various tumors.

Orthotopic tumorgrafts in nude mice: A new method to study human prostate cancer.

In vivo model systems in prostate cancer research that authentically reproduce tumor growth are still sparse. While orthotopic implantation is technically difficult, particularly in the mouse, most models favor subcutaneous tumor growth. This however provides little information about natural tumor growth behavior and tumor stroma interaction. Furthermore, established prostate cancer cell lines grown as in vivo xenografts are not able to reflect the variety of tumor specific growth patterns and growth behavior in men. Primary cell cultures are difficult to handle and an induction of orthotopic tumors has not been successful yet. Therefore, a tumorgraft model using tumor tissue from prostatectomy specimens was developed.

Combination of p16 INK4a -Ki67 Immunocytology and HPV Polymerase Chain Reaction for the Noninvasive Analysis of HPV Involvement in Head and Neck Cancer

We recently read an interesting article by Linxweiler et al, who reported the use of p16-Ki67 immunocytochemistry combined with human papillomavirus (HPV) testing on cytological specimens for the assessment of HPV involvement in head and neck squamous cell carcinoma (HNSCC). Their findings regarding brush cytology and HPV testing are in agreement with the results of our previous study. In fact, we recently reported that abnormal brush cytology is strongly associated with a diagnosis of HNSCC and that HPV testing on cytobrushing specimens from patients with HNSCC is feasible and reliable. Linxweiler et al found a very high sensitivity (98%) and specificity (100%) for head and neck brush cytology, although the estimation of sensitivity based on an analytic population that was composed mostly of patients with cancer (50 of 65 patients) has to be regarded with caution. In fact, a recent work highlighted that disease prevalence affects test characteristics, including sensitivity. In addition, the high sensitivity reported by Linxweiler et al may depend on the fact that the samples were partly obtained during a panendoscopy, a procedure that guarantees a more thorough collection of cytological specimens compared with an ambulatory setting. Indeed, in an ambulatory setting, we collected 100 cytobrushing specimens from patients with HNSCC, and detected abnormal cells in only 77 of them (77%). Linxweiler et al also claimed that false-negative results regarding HPV status assessed on the cytological samples may be avoided by screening the samples for the presence of cancer cells prior to HPV testing. We performed the HPV test on 68 paired cytological-histological specimens from patients with HNSCC (Cohen kappa, 0.84) and based on our results, we only partly agree with the authors. In fact, among 9 morphologically negative cytobrushing specimens that corresponded to HPVpositive tumors, 3 specimens tested negative for HPV (thus representing false-negative results), whereas the other 6 were positive for HPV type 16, a finding that is in agreement with the respective tumor tissue. These findings demonstrate that cytological brushings may yield a reliable HPV test result despite the fact that they do not contain neoplastic cells. Although the performance of head and neck cytology can only be evaluated on a population-based sample, we believe that the study by Linxweiler et al represents a strong contribution toward promoting the use of brush cytology in patients with HNSCC for the assessment of HPV involvement in such tumors.

Combination of p16INK4a/Ki67 immunocytology and hpv polymerase chain reaction for the noninvasive analysis of HPV involvement in head and neck cancer: p16-Ki67 Dual Stain in HNSCC

High‐risk human papillomavirus (HPV) infection has been identified as a relevant risk for the development of head and neck squamous cell carcinomas (HNSCCs). As HPV status has also gained a role as a prognostic and predictive biomarker for this entity, there is a growing demand for valid HPV testing in HNSCC patients

The Fuhrman grading system has no prognostic value in patients with nonsarcomatoid chromophobe renal cell carcinoma

The prognostic value of the Fuhrman nuclear grading system has been questioned for chromophobe renal cell carcinoma (chRCC) because this subtype frequently displays nuclear and nucleolar pleomorphism. The present study reevaluates this grading system in a series of patients with nonsarcomatoid chRCC. We identified 176 patients (3.6%) with nonsarcomatoid chRCC in a total of 4897 patients who underwent surgery for renal cell carcinoma at 5 centers in Germany between 1990 and 2010. The mean follow-up was 51.1 months. The 3 groups (G1 versus G2 versus G3/4) were comparable in terms of age, sex, tumor diameter, and lymph node metastasis. They only differed significantly in tumor stage (P = .01) and the incidence of synchronous visceral metastasis (P = .04). The 5-year cancer-specific survival rates were 84.4% for G1 (n = 32), 84.3% for G2 (n = 108), and 74.1% for G3/4 tumors (n = 33) (P = .58). Accordingly, multivariate analysis including age, sex, tumor stage, and metastatic disease did not identify Fuhrman grading as an independent predictor of cancer-specific survival in patients with chRCC (P = .4). We were able to demonstrate in a large multicenter cohort that the Fuhrman grading system does not qualify as a prognostic tool in patients with chRCC.

Effect of 3q oncogenes SEC62 and SOX2 on lymphatic metastasis and clinical outcome of head and neck squamous cell carcinomas

Chromosome 3q26 amplification represents a frequent alteration in head and neck squamous cell carcinomas (HNSCCs). Overexpression of 3q26 encoded genes SEC62 and SOX2 was detected in various cancers, including HNSCCs, indicating their potential function as oncogenes. In our study, we elucidated the function of SEC62 and SOX2 in HNSCC patients, with a main focus on their effect on lymphatic metastasis and patient survival. We analyzed SEC62 and SOX2 expression in tissue specimens from 65 HNSCC patients and 29 patients with cervical cancer of unknown primary (CUP); a higher SEC62 and lower SOX2 expression was observed in the lymph node metastases from HNSCC patients compared with the respective primary tumor. Lymph node metastases from CUP patients showed higher SEC62 and lower SOX2 expression compared with lymph node metastases from HNSCC patients. When proceeding from the N1 to the N3 stage, SEC62 expression in the lymph node metastases showed an increase and SOX2 expression showed a decrease. Moreover, both genes showed a highly significant relevance as prognostic biomarkers, with the worst prognosis for patients with high SEC62 and low SOX2 expression levels. In functional analyses, knockdown of SEC62 resulted in an inhibition of HNSCC cell migration while, conversely, SEC62 and SOX2 overexpression stimulated cell migration. Taken together, our study showed that the expression of the 3q oncogenes SEC62 and SOX2 affects lymphatic metastasis and cell migration in HNSCC and CUP patients and has a high prognostic relevance in these diseases.

Histological and Biochemical Findings in Membranous Cataract

Background: In this report we present a patient with unilateral membranous cataract and describe the histological and biochemical findings accompanying this rare condition. Methods: The patient underwent an uneventful cataract extraction. Aqueous humor (20 µl) was aspirated from the anterior chamber intraoperatively and processed for fibroblast growth factor (FGF) and epidermal growth factor (EGF) using an immunoassay method (ELISA). The lens material was subjected to histological examination. Results: The patient had increased levels of FGF and EGF in the aqueous humor, as measured by ELISA. Histological examination of the lens material showed a marked fibrous metaplasia and thickening of the anterior lens capsule, while the lens epithelial cells were transformed to active myofibroblasts which generated a fibrous matrix of collagen lamellae. Unfortunately, visual function was not restored postoperatively due to underlying amblyopia. Conclusions: Our histological and biochemical findings suggest that FGF and EGF may play a key role in the formation of membranous cataract, and therefore their impact on lens physiology should be further investigated.

Identification of SEC62 as a potential marker for 3q amplification and cellular migration in dysplastic cervical lesions

BackgroundChromosome 3 amplification affecting the 3q26 region is a common genomic alteration in cervical cancer, typically marking the transition of precancerous intraepithelial lesions to an invasive phenotype. Though potential 3q encoded target genes of this amplification have been identified, a functional correlation of potential oncogenic function is still missing. In this study, we investigated copy number changes and the expression level of SEC62 encoded at 3q26.2 as a new potential 3q oncogene in dysplastic cervical lesions and analyzed its role in cervical cancer cell biology.MethodsExpression levels of Sec62 and vimentin were analyzed in liquid based cytology specimens from 107 women with varying grades of cervical dysplasia ranging from normal cases to cancer by immunofluorescence cytology. Additionally, a subset of 20 representative cases was used for FISH analyses targeting SEC62. To further explore the functional role of Sec62 in cervical cancer, HeLa cells were transfected with a SEC62 plasmid or SEC62 siRNA and analyzed for their proliferation and migration potential using real-time monitoring and trans-well systems as well as changes in the expression of EMT markers.ResultsFISH analyses of the swabbed cells showed a rising number of SEC62 gains and amplifications correlating to the grade of dysplasia with the highest incidence in high grade squamous intraepithelial lesions and squamous cell carcinomas. When analyzing the expression level of Sec62 and vimentin, we found a gradually increasing expression level of both proteins according to the severity of the dysplasia. In functional analyses, SEC62 silencing inhibited and SEC62 overexpression stimulated the migration of HeLa cells with only marginal effects on cell proliferation, the expression level of EMT markers and the cytoskeleton structure.ConclusionsOur study suggests SEC62 as a target gene of 3q26 amplification and a stimulator of cellular migration in dysplastic cervical lesions. Hence, SEC62 could serve as a potential marker for 3q amplification, providing useful information about the dignity and biology of dysplastic cervical lesions.

Histology and Function: Analyzing the Uvular Muscle

Objective Virtual surgery and virtual patients necessitate quantitative data on the area of interest. The study was conducted to exactly describe the embryonic and fetal uvular muscle (MU), relevant for clinical as well as virtual surgery and virtual patient generation. Method Serially sectioned viscerocrania of 10 aborted embryos and fetuses underwent three-dimensional reconstruction to obtain detailed anatomic data and perform finite element analyses. Results The MU was paired in 80% of cases, while 20% allowed no clear-cut distinction. The MU merged with the levator muscle beneath the palatal aponeurosis without a hard palate insertion. Superior longitudinal central fibers ran below the nasal mucosa, and few circular peripheral fibers crossed in the central third to the contralateral side. This was seen in 30% of the paired muscles and in all cases when no differentiation was possible; about 40% to 80% MU fibers crossed to the ipsi lateral and contralateral palatopharyngeus muscle behind the levator loop. MU fibers inserted 60% nasal and 40% oral to the basal membrane at the middle third of the macroscopic uvula, made of loose connective tissue and salivary glands. The results of the finite element simulation of the uvula showed no distinct patterns or distributions of local stress. Conclusions Detailed anatomical study supported the concept of mediocranial MU repositioning during corrective surgery, although the impact is minor to the levator muscles action. Future mathematical models describing effects of such a maneuver should integrate surrounding structures.