Autophagy-enhancing drug carbamazepine diminishes hepatocellular death in fibrinogen storage disease.

Fibrinogen storage disease (FSD) is a rare autosomal-dominant hereditary disorder characterized by hypofibrinogenemia and accumulation of fibrinogen aggregates within the hepatocellular endoplasmatic reticulum (ER). Some FSD patients present with elevated amino-transferases and fibrosis/cirrhosis similar to alpha-1-antitrypsin deficiency (ATD), also an ER storage disease. Pharmacological stimulation of autophagy has been shown to mediate clearance of protein aggregates and halt progression of liver fibrosis in in vivo models of ATD. Our aim was to evaluate the presence of autophagy and a possible response to autophagy-enhancing therapy in patients with FSD. Hepatic fibrosis was assessed by transient elastography in 2 newly identified FSD families with fibrinogen Aguadilla and Brescia mutations, encompassing 8 affected members. Available liver biopsies were assessed for autophagy. Two patients, who had had elevated alanine amino-transaminase levels (2-5 above upper limit of normal), were treated with the autophagy enhancer carbamazepine (CBZ). Transient elastography did not show evidence of significant fibrosis in any affected family members. Quantitative electron microscopy of one patient showed a 5.15-fold increase of late stage autophagocytic vacuoles compared to control livers. CBZ at low anticonvulsive treatment levels led to rapid normalization of alanine-aminotransferase and decrease of caspase-cleaved and uncleaved cytokeratin-18 fragments (M30 and M65). These effects reversed after discontinuation of treatment. Response to CBZ may be mediated by pharmacologically enhanced autophagy resulting in reduction of aggregate-related toxicity in FSD. These results suggest clinical applicability of pharmacological stimulation of autophagy in FSD, but potentially also in other related disorders.

Arteriolar vascular smooth muscle cell differentiation in benign nephrosclerosis.

BACKGROUND: Benign nephrosclerosis (bN) is the most prevalent form of hypertensive damage in kidney biopsies. It is defined by early hyalinosis and later fibrosis of renal arterioles. Despite its high prevalence, very little is known about the contribution of arteriolar vascular smooth muscle cells (VSMCs) to bN. We examined classical and novel candidate markers of the normal contractile and the pro-fibrotic secretory phenotype of VSMCs in arterioles in bN. METHODS: Sixty-three renal tissue specimens with bN and eight control specimens were examined by immunohistochemistry for the contractile markers caldesmon, alpha-smooth muscle actin (alpha-SMA), JunB, smoothelin and the secretory marker S100A4 and by double stains for caldesmon or smoothelin with S100A4. RESULTS: Smoothelin immunostaining showed an inverse correlation with hyalinosis and fibrosis scores, while S100A4 correlated with fibrosis scores only. Neither caldesmon, alpha-SMA nor JunB correlated with hyalinosis or fibrosis scores. Cells in the arteriolar wall were exclusively positive either for caldesmon/smoothelin or S100A4. CONCLUSIONS: This is the first systematic analysis of VSMC differentiation in bN. The results suggest that smoothelin is the most sensitive marker for the contractile phenotype and that S100A4 could be a novel marker for the secretory phenotype in vivo. The other markers did not seem to differentiate these phenotypes in bN. Thus, VSMC phenotype markers should be defined in the context of the vessel segment and disease under examination. S100A4 could not only be a marker of pro-fibrotic secretory VSMCs in bN but also an important mediator of arteriolar fibrosis.

Lobular neoplasia and invasive lobular breast cancer: Inter-observer agreement for histological grading and subclassification.

Lobular neoplasia (LN), invasive lobular breast cancer (ILBC) and related pleomorphic variants represent a distinct group of neoplastic mammary gland lesions. This study assessed the inter-observer agreement of histological grading in a series of ILBC and LN. 54 cases (36x ILBC, 18x LN) were evaluated by 17 observers. 3978 classification calls on various histological features, including nuclear grade, proliferative activity (Ki67 immunohistochemistry, categorical scoring), histological grade and pleomorphism were obtained. Pairwise Cohen's kappa values were calculated and compared between various features and different observer subsets with variable histomorphological experience. In ILBC, pairwise inter-observer agreement for histological grade ranged from poor to almost perfect concordance and was higher in advanced and experienced histopathologists compared with beginners (P < 0.001). Agreement for proliferation (Ki67) ranged from slight to almost perfect concordance and was also higher in advanced and experienced histopathologists (P < 0.001). Considering different features, agreement for proliferation (Ki67) was superior to agreement for histological grade and nuclear grade, even among advanced and experienced histopathologists (P < 0.001). In LN, agreement for B-classification ranged from poor to almost perfect concordance and was higher in advanced and experienced histopathologists (P < 0.001). Considering different features, agreement for proliferation (Ki67 in LN) was superior to subclassification agreement based on conventional features, such as acinar distention and nuclear grade (P < 0.001). In summary, pairwise inter-observer concordance of histological grading of ILBC and LN is dependent on histomorphological experience. Assessment of proliferation by Ki67 immunohistochemistry is associated with favorable inter-observer agreement and can improve histological grading of ILBC as well as LN.

High frequency of lobular breast cancer in distant metastases to the orbit.

Metastasis to the periocular soft tissue of the orbit is a rare manifestation of metastatic cancer. Infiltrating lobular breast cancer (ILBC) is a special breast cancer subtype, which accounts for 10-15% of all mammary carcinomas and for ~1% of all malignancies. Here, we report on a high frequency of lobular breast cancer in patients with orbital metastases identified in an original series of metastatic tumor specimens and by a systematic literature review. A series of 14 orbital metastases was compiled from formalin-fixed paraffin-embedded archival tissues. All cases were subjected to histological re-review and detailed immunophenotypical characterization. In addition, we performed a meta-analysis of 68 previously published case reports describing orbital metastases, with special reference to breast cancer subtypes. Based on clinical history, histomorphology, immunophenotype, and/or comparison with matched primary tumors, orbital metastases were derived from breast cancer in 8/14 cases, seven of which were classified as metastatic lobular breast cancer. Other entities included non-small cell lung cancer (4/14), infiltrating ductal breast cancer (1/14), prostate cancer (1/14) and adenocarcinoma of the esophagus (1/14). In line with this original series of orbital metastases, lobular breast cancer was the most common malignancy in 72 patients with orbital metastases described in 68 independent case reports. In conclusion, lobular breast cancer represents the cancer subtype with the highest prevalence among orbital metastases. The high frequency of ILBC in orbital metastases illustrates the special metastatic behavior of this tumor entity and may have implications for the understanding of the organotropism of metastatic lobular breast cancer.

Renal phospholipidosis possibly induced by ranolazine.

A 76-year-old male Caucasian patient was treated in our hospital for acutely decompensated heart failure due to restrictive cardiomyopathy. Acute-on-chronic kidney failure developed with serum creatinine rising from 160 to 345 µmol/L (1.8-3.9 mg/dL); therefore, a kidney biopsy was performed. Besides secondary focal-segmental glomerulosclerosis and minimal amyloidosis, histological analysis showed zebra bodies in the cytoplasm of some podocytes, suggesting renal phospholipidosis (PL). Possible causes for this storage disorder encompass Fabry's disease, in rare cases silicosis, and an iatrogenic drug-induced aetiology. The main suspects are cationic amphiphilic drugs, such as amiodarone and chloroquine. The only cationic amphiphilic drug our patient had taken was the anti-anginal ranolazine, a compound not yet associated with PL. The patient had taken ranolazine for diastolic dysfunction over a period of 9 months until 6 weeks before renal biopsy. In the absence of a hereditary disorder, silicosis and well-known pharmaceutical triggers, a causative role of ranolazine seems likely, and this drug should be considered in the differential diagnosis of drug-induced PL.

Synovial sarcoma of the kidney in a young patient with a review of the literature.

Synovial sarcoma (SS) is a soft tissue, generally deep seated neoplasms that occurs generally in the proximity of large joints. We report of a case of a 33-year-old man who was diagnosed with primary SS of the kidney which is an extremely rare tumor that accounts for less than 2% of malignant renal tumors. Contemporary management of renal synovial sarcoma includes surgical resection and ifosfamide-based chemotherapy and they remain the mainstay of therapy of synovial sarcoma, which is often applied, combined as part of an aggressive treatment approach. Fewer than 50 patients have been described in the English literature. Physicians should be aware of the possibility of malignancy in cystic renal masses and raise the suspicion of synovial sarcoma, especially when patients with renal masses are young adults. Along with the case report a literature review on primary synovial sarcomas of the kidney is provided with focus on the renal tumors' differential diagnosis.

Comprehensive analysis of glomerular mRNA expression of pro- and antithrombotic genes in atypical haemolytic-uremic syndrome (aHUS).

Atypical haemolytic-uremic syndrome (aHUS) is, in most cases, due to hereditary or acquired defects in complement regulation and a life-threatening disease. Despite the rapidly grown knowledge about the primary defects in aHUS, the pathogenesis that links complement dysregulation with microthrombus formation in aHUS is still unknown. Thus, we examined the glomerular microvascular expression of pro- and antithrombotic genes. Glomeruli were microdissected from 12 archival paraffin-embedded biopsies with aHUS and from seven control biopsies. Glomerular mRNA expression was quantified by single real-time PCR reactions after preamplification. In addition immunostains were performed for plasminogen activator inhibitor 1 (PAI-1) and for tissue plasminogen activator (tPA). Results were compared between cases and controls and with clinical data. Glomeruli in aHUS had increased mRNA expression of antifibrinolytic, prothrombotic PAI-1, antithrombotic thrombomodulin (THBD) and CD73 and decreased expression of profibrinolytic, antithrombotic tPA compared to controls. Impaired fibrinolysis due to increased microvascular expression of the antifibrinolytic PAI-1 in combination with the decreased expression of the profibrinolytic tPA seems to be a final common pathway in renal thrombotic microangiopathy that is also effective in aHUS. The concomitant induction of antithrombotic transcripts likely indicates counterregulatory efforts, demonstrating that the capillary bed is not a passive victim of complement attack. Future research should investigate if and how complement activation could induce the reported shift in the expression of PAI-1 and tPA.

Glomerular mRNA expression of prothrombotic and antithrombotic factors in renal transplants with thrombotic microangiopathy.

BACKGROUND: Thrombotic microangiopathy (TMA) in renal transplants (rTx-TMA) is a serious complication and is usually either recurrent TMA (RecTMA) due to humoral rejection (HR-TMA) or due to calcineurin inhibitor toxicity (CNI-TMA). Although the triggers are known, our knowledge about the thrombogenic transcriptome changes in the microvessels is rudimentary. METHODS: We examined the expression of several prothrombotic and antithrombotic genes in 25 biopsies with rTx-TMA (6 RecTMA, 9 HR-TMA, and 10 CNI-TMA) and 8 controls. RNA from microdissected glomeruli of paraffin-embedded tissue was isolated and mRNA transcripts were quantified with real-time polymerase chain reaction after preamplification. Results were correlated with clinicopathologic parameters. RESULTS: Glomerular mRNA expression of KLF2, KLF4, and tPA was lower and that of PAI-1 was higher in rTx-TMA than in the controls. Glomerular mRNA expression of KLF2 and KLF4 correlated with that of tPA and inversely with that of PAI-1 in rTx-TMA. The mRNA expression of complement regulators CD46 and CD59 were higher in rTx-TMA than in the controls. Only in HR-TMA were glomerular ADAMTS13 and CD55 down-regulated. CONCLUSIONS: The glomerular capillary bed seems to contribute to all subtypes of rTx-TMA by down-regulation of the endothelial transcription factors KLF2 and KLF4, indicating dedifferentiation with subsequent up-regulation of PAI-1 and down-regulation of tPA, resulting in inhibition of local fibrinolysis. Decreased glomerular expression of ADAMTS13 and CD55 could be an additional pathway toward microthrombosis exclusively in HR-TMA.

Rationale and design of the RIACT-study: a multi-center placebo controlled double blind study to test the efficacy of RItuximab in Acute Cellular tubulointerstitial rejection with B-cell infiltrates in renal Transplant patients: study protocol for a randomized controlled trial.

BACKGROUND: Acute kidney allograft rejection is a major cause for declining graft function and has a negative impact on the long-term graft survival. The majority (90%) of acute rejections are T-cell mediated and, therefore, the anti-rejection therapy targets T-cell-mediated mechanisms of the rejection process. However, there is increasing evidence that intragraft B-cells are also important in the T-cell-mediated rejections. First, a significant proportion of patients with acute T-cell-mediated rejection have B-cells present in the infiltrates. Second, the outcome of these patients is inferior, which has been related to an inferior response to the conventional anti-rejection therapy. Third, treatment of these patients with an anti-CD20 antibody (rituximab) improves the allograft outcome as reported in single case observations and in one small study. Despite the promise of these observations, solid evidence is required before incorporating this treatment option into a general treatment recommendation. METHODS/DESIGN: The RIACT study is designed as a randomized, double-blind, placebo-controlled, parallel group multicenter Phase III study. The study examines whether rituximab, in addition to the standard treatment with steroid-boli, leads to an improved one-year kidney allograft function, compared to the standard treatment alone in patients with acute T-cell mediated tubulointerstitial rejection and significant B-cell infiltrates in their biopsies. A total of 180 patients will be recruited. DISCUSSION: It is important to clarify the relevance of anti-B cell targeting in T-cell mediated rejection and answer the question whether this novel concept should be incorporated in the conventional anti-rejection therapy. TRIAL REGISTRATION: Clinical trials gov. number: NCT01117662.