Direct cellular reprogramming enables development of viral T antigen-driven Merkel cell carcinoma in mice

Merkel cell carcinoma (MCC) is an aggressive neuroendocrine skin cancer that frequently carries an integrated Merkel cell polyomavirus (MCPyV) genome and expresses viral transforming antigens (TAgs). MCC tumor cells also express signature genes detected in skin-resident, postmitotic Merkel cells, including atonal bHLH transcription factor 1 (ATOH1), which is required for Merkel cell development from epidermal progenitors. We now report the use of in vivo cellular reprogramming, using ATOH1, to drive MCC development from murine epidermis. We generated mice that conditionally expressed MCPyV TAgs and ATOH1 in epidermal cells, yielding microscopic collections of proliferating MCC-like cells arising from hair follicles. Immunostaining of these nascent tumors revealed p53 accumulation and apoptosis, and targeted deletion of transformation related protein 53 (Trp53) led to development of gross skin tumors with classic MCC histology and marker expression. Global transcriptome analysis confirmed the close similarity of mouse and human MCCs, and hierarchical clustering showed conserved upregulation of signature genes. Our data establish that expression of MCPyV TAgs in ATOH1-reprogrammed epidermal cells and their neuroendocrine progeny initiates hair follicle–derived MCC tumorigenesis in adult mice. Moreover, progression to full-blown MCC in this model requires loss of p53, mimicking the functional inhibition of p53 reported in human MCPyV-positive MCCs.

Transgenic expression of interferon-γ in mouse stomach leads to inflammation, metaplasia, and dysplasia

Gastric adenocarcinoma is one of the leading causes of cancer mortality worldwide. It arises through a stepwise process that includes prominent inflammation with expression of interferon-γ (IFN-γ) and multiple other pro-inflammatory cytokines. We engineered mice expressing IFN-γ under the control of the stomach-specific H(+)/K(+) ATPase β promoter to test the potential role of this cytokine in gastric tumorigenesis. Stomachs of H/K-IFN-γ transgenic mice exhibited inflammation, expansion of myofibroblasts, loss of parietal and chief cells, spasmolytic polypeptide expressing metaplasia, and dysplasia. Proliferation was elevated in undifferentiated and metaplastic epithelial cells in H/K-IFN-γ transgenic mice, and there was increased apoptosis. H/K-IFN-γ mice had elevated levels of mRNA for IFN-γ target genes and the pro-inflammatory cytokines IL-6, IL-1β, and tumor necrosis factor-α. Intracellular mediators of IFN-γ and IL-6 signaling, pSTAT1 and pSTAT3, respectively, were detected in multiple cell types within stomach. H/K-IFN-γ mice developed dysplasia as early as 3 months of age, and 4 of 39 mice over 1 year of age developed antral polyps or tumors, including one adenoma and one adenocarcinoma, which expressed high levels of nuclear β-catenin. Our data identified IFN-γ as a pivotal secreted factor that orchestrates complex changes in inflammatory, epithelial, and mesenchymal cell populations to drive pre-neoplastic progression in stomach; however, additional alterations appear to be required for malignant conversion.

Basal cell carcinomas in mice arise from hair follicle stem cells and multiple epithelial progenitor populations

Uncontrolled Hedgehog (Hh) signaling leads to the development of basal cell carcinoma (BCC), the most common human cancer, but the cell of origin for BCC is unclear. While Hh pathway dysregulation is common to essentially all BCCs, there exist multiple histological subtypes, including superficial and nodular variants, raising the possibility that morphologically distinct BCCs may arise from different cellular compartments in skin. Here we have shown that induction of a major mediator of Hh signaling, GLI2 activator (GLI2ΔN), selectively in stem cells of resting hair follicles in mice, induced nodular BCC development from a small subset of cells in the lower bulge and secondary hair germ compartments. Tumorigenesis was markedly accelerated when GLI2ΔN was induced in growing hair follicles. In contrast, induction of GLI2ΔN in epidermis led to the formation of superficial BCCs. Expression of GLI2ΔN at reduced levels in mice yielded lesions resembling basaloid follicular hamartomas, which have previously been linked to low-level Hh signaling in both mice and humans. Our data show that the cell of origin, tissue context (quiescent versus growing hair follicles), and level of oncogenic signaling can determine the phenotype of Hh/Gli-driven skin tumors, with high-level signaling required for development of superficial BCC-like tumors from interfollicular epidermis and nodular BCC-like tumors from hair follicle stem cells.

Study on the prevalence and incidence of urolithiasis in Germany comparing the years 1979 vs. 2000

OBJECTIVES

In 1979, we conducted a representative study to determine the prevalence and incidence of urolithiasis in Germany. Significant progress in stone therapy and changes in nutritional and environmental factors since then consequently led to a second study in 2001 under the same conditions as in 1979.

METHODS

A representative sample of 7500 persons from all over Germany was questioned on the occurrence of urinary stones during their lifetimes (prevalence) and on acute urolithiasis in 2000 (incidence). Additionally, data were collected on urinary stone therapy and metaphylaxis. The current data were then compared with those from 1979.

RESULTS

Prevalence has risen from 4% to 4.7% from 1979 to 2001. 9.7% of the 50-64 year old males in 2000 had already had urinary stones (females: 5.9%). The current recurrence rate of urinary stones was estimated to be 42%. In the year 2000, the incidence of urolithiasis in Germany was found to be 1.47% (1979: 0.54%). Over 40% of the stones were passed spontaneously.

CONCLUSION

There has been a marked increase in the prevalence and incidence of urolithiasis in Germany within the last 22 years. This probably results from improvements in clinical-diagnostic procedures, changes in nutritional and environmental factors and a general apathy towards metabolic clarification and metaphylaxis.

Study on the prevalence and incidence of urolithiasis in Germany comparing the years 1979 vs. 2000

OBJECTIVES

In 1979, we conducted a representative study to determine the prevalence and incidence of urolithiasis in Germany. Significant progress in stone therapy and changes in nutritional and environmental factors since then consequently led to a second study in 2001 under the same conditions as in 1979.

METHODS

A representative sample of 7500 persons from all over Germany was questioned on the occurrence of urinary stones during their lifetimes (prevalence) and on acute urolithiasis in 2000 (incidence). Additionally, data were collected on urinary stone therapy and metaphylaxis. The current data were then compared with those from 1979.

RESULTS

Prevalence has risen from 4% to 4.7% from 1979 to 2001. 9.7% of the 50-64 year old males in 2000 had already had urinary stones (females: 5.9%). The current recurrence rate of urinary stones was estimated to be 42%. In the year 2000, the incidence of urolithiasis in Germany was found to be 1.47% (1979: 0.54%). Over 40% of the stones were passed spontaneously.

CONCLUSION

There has been a marked increase in the prevalence and incidence of urolithiasis in Germany within the last 22 years. This probably results from improvements in clinical-diagnostic procedures, changes in nutritional and environmental factors and a general apathy towards metabolic clarification and metaphylaxis.

[ESWL centers and determination of urinary calculus etiology. Results of a survey of 150 ESWL centers]

Questionnaires were mailed anonymously to 150 German shock wave centers. Twenty questions addressed the following areas of interest: Facilities of the extracorporeal shock wave lithotripsy (ESWL) center (technical, personnel, laboratory, etc.) Cooperation at ESWL center with referring urologists Laboratory facilities versus actual metabolic work-up. The return rate was 114 of 150 (76%). Surprisingly, at 58% of the centers the average number of treatments is less than two per day. In 30% of the centers only chemical stone analysis is done! The final conclusion was that ESWL has largely replaced the causal metabolic work-up and subsequent metaphylaxis as a symptomatic measure against urolithiasis.

[Hinman syndrome. Pronounced renal failure as a sequela of pseudo-neurogenic disorder of bladder emptying]

The case of an eight year old girl is presented who was seen because of secondary enuresis and recurrent urinary tract infection. Detailed examinations revealed urinary retention and sustained renal insufficiency (Creatinine clearance: 11 ml/min x 1.73 m2) due to a pseudo-neurogenic bladder. After improvement of renal function by continuous bladder drainage, bladder dysfunction was successfully treated by medication (Phenoxybenzamine, Baclofen), conventional physical therapy and biofeedback.

[Ultrasonic diagnosis, computed tomography and lymphography of retroperitoneal lymphomas--re-evaluation of lymphography]

Regarding the present results and the review of literature, we are of the opinion that negative attitude towards lymphography is not justified. In diagnostic procedure, priority is given to sonography and computed tomography because of their non-invasiveness. Lymphography is indispensable in all cases where sonography or computed tomography show negative findings and where the therapy planning depends on evidence or exclusion of retroperitoneal lymphomas. In general the combination of both computed tomography and lymphography is the most sensitive and consequently, the safest method in the diagnosis of retroperitoneal lymphomas.

Extracorporeal shock wave lithotripsy of ureteral stones: clinical experience and experimental findings

ESWL of impacted ureteral or caliceal stones is not as successful as expected. To study this problem a model for extracorporeal shock wave lithotripsy of ureteral stones has been designed. After initial fragmentation of the outer shell of impacted stones during the first series of shock wave application those fragments are kept in place by external mucosal contact, creating a lot of new interfaces. Absorption or reflection of shock wave energy within this fragmented shell seems to be responsible for the poor success rate in these cases. In regard to our experimental and clinical results we advise pushing ureteral stones back into the renal collecting system by means of a ureteral catheter.