A bird's eye view on the use of whole exome sequencing in rare congenital ophthalmic diseases

Phenotypic and genotypic heterogeneity in congenital ocular diseases, especially in anterior segment dysgenesis (ASD), have created challenges for proper diagnosis and classification of diseases. Over the last decade, genomic research has indeed boosted our understanding in the molecular basis of ASD and genes associated with both autosomal dominant and recessive patterns of inheritance have been described with a wide range of expressivity. Here we describe the molecular characterization of a cohort of 162 patients displaying isolated or syndromic congenital ocular dysgenesis. Samples were analyzed with diverse techniques, such as direct sequencing, multiplex ligation-dependent probe amplification, and whole exome sequencing (WES), over 20 years. Our data reiterate the notion that PAX6 alterations are primarily associated with ASD, mostly aniridia, since the majority of the cohort (66.7%) has a pathogenic or likely pathogenic variant in the PAX6 locus. Unexpectedly, a high fraction of positive samples (20.3%) displayed deletions involving the 11p13 locus, either partially/totally involving PAX6 coding region or abolishing its critical regulatory region, underlying its significance. Most importantly, the use of WES has allowed us to both assess variants in known ASD genes (i.e., CYP1B1, ITPR1, MAB21L1, PXDN, and PITX2) and to identify rarer phenotypes (i.e., MIDAS, oculogastrointestinal-neurodevelopmental syndrome and Jacobsen syndrome). Our data clearly suggest that WES allows expanding the analytical portfolio of ocular dysgenesis, both isolated and syndromic, and that is pivotal for the differential diagnosis of those conditions in which there may be phenotypic overlaps and in general in ASD.

Cyclometalated and NNN Terpyridine Ruthenium Photocatalysts and Their Cytotoxic Activity

The cyclometalated terpyridine complexes [Ru(η2-OAc)(NC-tpy)(PP)] (PP = dppb 1, (R,R)-Skewphos 4, (S,S)-Skewphos 5) are easily obtained from the acetate derivatives [Ru(η2-OAc)2(PP)] (PP = dppb, (R,R)-Skewphos 2, (S,S)-Skewphos 3) and tpy in methanol by elimination of AcOH. The precursors 2, 3 are prepared from [Ru(η2-OAc)2(PPh3)2] and Skewphos in cyclohexane. Conversely, the NNN complexes [Ru(η1-OAc)(NNN-tpy)(PP)]OAc (PP = (R,R)-Skewphos 6, (S,S)-Skewphos 7) are synthesized in a one pot reaction from [Ru(η2-OAc)2(PPh3)2], PP and tpy in methanol. The neutral NC-tpy 1, 4, 5 and cationic NNN-tpy 6, 7 complexes catalyze the transfer hydrogenation of acetophenone (S/C = 1000) in 2-propanol with NaOiPr under light irradiation at 30 °C. Formation of (S)-1-phenylethanol has been observed with 4, 6 in a MeOH/iPrOH mixture, whereas the R-enantiomer is obtained with 5, 7 (50-52% ee). The tpy complexes show cytotoxic activity against the anaplastic thyroid cancer 8505C and SW1736 cell lines (ED50 = 0.31-8.53 µM), with the cationic 7 displaying an ED50 of 0.31 µM, four times lower compared to the enantiomer 6.

Dihydrotanshinone I exhibits antitumor effects via β-catenin downregulation in papillary thyroid cancer cell lines

Thyroid cancer is the most common endocrine carcinoma and, among its different subtypes, the papillary subtype (PTC) is the most frequent. Generally, PTCs are well differentiated, but a minor percentage of PTCs are characterized by a worse prognosis and more aggressive behavior. Phytochemicals, naturally found in plant products, represent a heterogeneous group of bioactive compounds that can interfere with cell proliferation and the regulation of the cell cycle, taking part in multiple signaling pathways that are often disrupted in tumor initiation, proliferation, and progression. In this work, we focused on 15,16-dihydrotanshinone I (DHT), a tanshinone isolated from Salvia miltiorrhiza Bunge (Danshen). We first evaluated DHT biological effect on PTC cells regarding cell viability, colony formation ability, and migration capacity. All of these parameters were downregulated by DHT treatment. We then investigated gene expression changes after DHT treatment by performing RNA-seq. The analysis revealed that DHT significantly reduced the Wnt signaling pathway, which plays a role in various diseases, including cancer. Finally, we demonstrate that DHT treatment decreases protein levels of β-catenin, a final effector of canonical Wnt signaling pathway. Overall, our data suggest a possible use of this nutraceutical as an adjuvant in the treatment of aggressive papillary thyroid carcinoma.

GSK2801 Reverses Paclitaxel Resistance in Anaplastic Thyroid Cancer Cell Lines through MYCN Downregulation

Anaplastic thyroid cancer (ATC) is a very rare, but extremely aggressive form of thyroid malignancy, responsible for the highest mortality rate registered for thyroid cancer. Treatment with taxanes (such as paclitaxel) is an important approach in counteracting ATC or slowing its progression in tumors without known genetic aberrations or those which are unresponsive to other treatments. Unfortunately, resistance often develops and, for this reason, new therapies that overcome taxane resistance are needed. In this study, effects of inhibition of several bromodomain proteins in paclitaxel-resistant ATC cell lines were investigated. GSK2801, a specific inhibitor of BAZ2A, BAZ2B and BRD9, was effective in resensitizing cells to paclitaxel. In fact, when used in combination with paclitaxel, it was able to reduce cell viability, block the ability to form colonies in an anchor-independent manner, and strongly decrease cell motility. After RNA-seq following treatment with GSK2801, we focused our attention on MYCN. Based on the hypothesis that MYCN was a major downstream player in the biological effects of GSK2801, we tested a specific inhibitor, VPC-70619, which showed effective biological effects when used in association with paclitaxel. This suggests that the functional deficiency of MYCN determines a partial resensitization of the cells examined and, ultimately, that a substantial part of the effect of GSK2801 results from inhibition of MYCN expression.

Enantioselective Cytotoxicity of Chiral Diphosphine Ruthenium(II) Complexes Against Cancer Cells

The chiral cationic complex [Ru(η¹‐OAc)(CO)((R,R)‐Skewphos)(phen)]OAc (2^R), isolated from reaction of [Ru(η¹‐OAc)(η²‐OAc)(R,R)‐Skewphos)(CO)] (1^R) with phen, reacts with NaOPiv and KSAc affording [RuX(CO)((R,R)‐Skewphos)(phen)]Y (X=Y=OPiv 3^R; X=SAc, Y=OAc 4^R). The corresponding enantiomers 2^S‐4^S have been obtained from 1^S containing (S,S)‐Skewphos. Reaction of 2^R and 2^S with (S)‐cysteine and NaPF₆ at pH=9 gives the diastereoisomers [Ru((S)‐Cys)(CO)(PP)(phen)]PF₆ (PP=(R,R)‐Skewphos 2^R‐Cys; (S,S)‐Skewphos 2^S‐Cys). The DFT energetic profile for 2^R with (S)‐cysteine in H₂O indicates that aquo and hydroxo species are involved in formation of 2^R‐Cys. The stability of the ruthenium complexes in 0.9 % w/v NaCl solution, PBS and complete DMEM medium, as well as their n‐octanol/water partition coefficient (logP), have been evaluated. The chiral complexes show high cytotoxic activity against SW1736, 8505 C, HCT‐116 and A549 cell lines with EC₅₀ values of 2.8–0.04 μM. The (R,R)‐Skewphos derivatives show higher cytotoxicity compared to their enantiomers, 4^R (EC₅₀=0.04 μM) being 14 times more cytotoxic than 4^S against the anaplastic thyroid cancer 8505 C cell line.

Effects of Dihydrotanshinone I on Proliferation and Invasiveness of Paclitaxel-Resistant Anaplastic Thyroid Cancer Cells

ATC is a very rare, but extremely aggressive form of thyroid malignancy, responsible for the highest mortality rate registered for thyroid cancer. In patients without known genetic aberrations, the current treatment is still represented by palliative surgery and systemic mono- or combined chemotherapy, which is often not fully effective for the appearance of drug resistance. Comprehension of the mechanisms involved in the development of the resistance is therefore an urgent issue to suggest novel therapeutic approaches for this very aggressive malignancy. In this study, we created a model of anaplastic thyroid cancer (ATC) cells resistant to paclitaxel and investigated the characteristics of these cells by analyzing the profile of gene expression and comparing it with that of paclitaxel-sensitive original ATC cell lines. In addition, we evaluated the effects of Dihydrotanshinone I (DHT) on the viability and invasiveness of paclitaxel-resistant cells. ATC paclitaxel-resistant cells highlighted an overexpression of ABCB1 and a hyper-activation of the NF-κB compared to sensitive cells. DHT treatment resulted in a reduction of viability and clonogenic ability of resistant cells. Moreover, DHT induces a decrement of NF-κB activity in SW1736-PTX and 8505C-PTX cells. In conclusion, to the best of our knowledge, the results of the present study are the first to demonstrate the antitumor effects of DHT on ATC cells resistant to Paclitaxel in vitro.

Dihydrotanshinone exerts antitumor effects and improves the effects of cisplatin in anaplastic thyroid cancer cells

Anaplastic thyroid cancer (ATC) is the most aggressive type of thyroid cancer and is responsible for 20‑50% of thyroid cancer‑associated deaths. The absence of response to conventional treatments makes the search for novel therapeutics a clinical challenge. In the present study, the effects of 15,16‑dihydrotanshinone I (DHT), a tanshinone extracted from Salvia miltiorrhiza Bunge (Danshen), which has previously been shown to possess anticancer activity, were examined in two human ATC cell lines. DHT significantly reduced cell viability, which was coupled with an increase in apoptosis. DHT administration also reduced the colony‑forming ability and proliferation of these cells in soft agar and downregulated the expression of epithelial‑to‑mesenchymal transition‑related genes. In addition, DHT significantly reduced MAD2 expression, a target of HuR with a relevant role in ATC. Finally, cotreatment with cisplatin and DHT has a greater effect on cell viability than each compound alone. In conclusion, to the best of our knowledge, the present study is the first to demonstrate that DHT exerts antitumor effects on ATC cells by reducing MAD2 expression levels. Moreover, a synergistic effect of DHT with cisplatin was shown. Further in vivo studies are required to assess this phytochemical compound as a potential adjuvant for the treatment of ATC.

Longitudinal Dynamics of Circulating Tumor Cells and Circulating Tumor DNA for Treatment Monitoring in Metastatic Breast Cancer

Liquid biopsy-based biomarkers, including circulating tumor cells (CTCs) and circulating tumor DNA (ctDNA), are increasingly important for the characterization of metastatic breast cancer (MBC). The aim of the study was to explore CTCs and ctDNA dynamics to better understand their potentially complementary role in describing MBC.

METHODS

The study retrospectively analyzed 107 patients with MBC characterized with paired CTCs and ctDNA assessments and a second prospective cohort, which enrolled 48 patients with MBC. CTCs were immunomagnetically isolated and ctDNA was quantified and then characterized through next-generation sequencing in the retrospective cohort and droplet digital polymerase chain reaction in the prospective cohort. Matched pairs variations at baseline, at evaluation one (EV1), and at progression were tested through the Wilcoxon test. The prognostic role of ctDNA parameters was also investigated.

RESULTS

Mutant allele frequency (MAF) had a significant decrease between baseline and EV1 and a significant increase between EV1 and progression. Number of detected alterations steadily increased across timepoints, CTCs enumeration (nCTCs) significantly increased only between EV1 and progression. MAF dynamics across the main altered genes was then investigated. Plasma DNA yield did not vary across timepoints both in the retrospective cohort and in the prospective cohort, while the short fragments fraction showed a potential role as a prognostic biomarker.

CONCLUSION

nCTCs and ctDNA provide complementary information about prognosis and treatment benefit. Although nCTCs appeared to assess tumor biology rather than tumor burden, MAF may be a promising biomarker for the dynamic assessment of treatment response and resistance.

Refining neutropenia risk assessment in patients treated with first-line endocrine therapy (ET) and cyclin-dependent kinase 4/6 inhibitors (CDK4/6i) for metastatic breast cancer (MBC) through a cell-free DNA workflow (cfDNA)

1027

Background: The combination of ET and CDK4/6i is the current standard of care for hormone receptor (HR)-positive/HER2-negative MBC (luminal MBC), with neutropenia being the main dose limiting toxicity. We previously observed the potential association between leucocyte count (WBC) and different fractions of cell free circulating DNA (cfDNA) (Bortot et al 2020). The present study aimed to evaluate the feasibility of a cfDNA-based workflow as a new tool to assess the risk of treatment induced neutropenia. Methods: The study analyzed a prospective cohort 83 luminal MBC patients (pts) treated with first line ET and CDK4/6i in the CRO-2018-56 multicenter study from 2018 to 2021. cfDNA was characterized through droplet digital PCR (ddPCR) based on different ACTB DNA fragments lengths: short (s), medium (m) and long (l). Blood samples were collected before treatment start (BL) and at the first clinical evaluation after 3 months (E1). Associations between clinical characteristics, neutropenia and cfDNA were explored through Kruskal Wallis, time to G3 neutropenia (NG3) (TTN) was analyzed through log-rank and Cox regression. Results: Neutropenia was G3 in 44 out of 83 pts (53%) and G4 in 2 pts (2%). Median TTN was 1.8 months, 60% of NG3 occurred within 3.7 months. Overall, 74 pts (89%) resolved toxicity within 7 days, 10 pts (12%) reduced CDK4/6i dose after NG3. BL neutrophils count (Neu) and WBC were significantly lower in pts that developed NG3 (P = 0.0013 and P = 0.0020 respectively). De novo metastatic pts had numerically higher Neu (median 4825 vs 3895), but only a numerically lower risk of NG3 was observed (HR 0.53 P = 0.064). Although bone involvement was not associated with risk of developing NG3, the total number of metastatic lesions was associated with higher NG3 (P = 0.0016). In particular, > 5 metastatic lesions were associated with higher NG3 risk (p = 0.013). E1 ACTB_m was significantly lower with respect to BL in pts that experienced NG3 (median 100% vs 16%, P = 0.0136 in NG3 no vs yes) with a consistent impact on the risk of NG3 (HR: 2.81, P = 0.025). No associations were observed for the other ACTB fragment length fractions. BL Neu and ACTB_m dichotomized at the median were then combined to describe 4 distinct TTN risk groups (P = 0.0006). Interestingly, pts with low BL Neu and low E1 ACTB_m had a median TTN of 0.9 months, while pts with high BL Neu and high E1 ACTB_m have not experienced NG3 after a median follow-up of 16.1 months. Conclusions: The present study proofed the concept of using cfDNA to provide clinically meaningful data not only about tumor biology, but also for a comprehensive patient assessment. Based on these results, a prospective study focused on a multiparametric neutropenia risk assessment will be started.

Liquid biopsy for baseline evaluation of tumor burden in patients with hormone receptor-positive, HER2-negative metastatic breast cancer: A proof of principle study

e13008

Background: Liquid biopsy-based biomarkers, including circulating tumor DNA (ctDNA), are increasingly important for the characterization of metastatic breast cancer (MBC). Currently, CA15.3 is the most commonly used serum marker for monitoring disease burden. To date, no liquid biopsy-based biomarkers have been proposed for this scope in clinical practice. Methods: The CRO-2018-56 multicenter study prospectively enrolled 83 patients (pts) with luminal-like MBC treated with first line endocrine therapy (ET) and CDK4/6 inhibitors. All pts were characterized for ctDNA through droplet digital PCR (ddPCR) in from 2018 to 2021. Clinicopathological and laboratory characteristics at baseline were tested for associations with tumor markers, ACTB fragments lengths, methylation status of ESR1 main promoters (expressed as promA and promB ratio, i.e., met_ratio) and ESR1/PIK3CA mutational status through Kruskal-Wallis test and Chi-square test. Prognosis was tested in terms of Progression Free Survival (PFS) and Overall Survival (OS) through log-rank test. Results: At baseline, in 26 (31%) pts disease was diagnosed as de novo metastatic, 66 (80%) pts had < 3 of metastatic sites, and 41 (49%) pts had < 5 of metastatic lesions. Bone metastases were detected in 53 (64%) pts, liver metastases in 21 (25%) pts, and lung lesions in 30 (36%) pts. A ctDNA-detected ESR1 mutation and a PIK3CA mutation were found in 15% of pts and in 34% pts, respectively. Met_ratio was > 1.5 in 35 (42%) of pts. Median CA15.3 was 48.2 U/mL and median CEA was 3.8 U/mL. Number of liver metastases and number of metastatic sites were significantly higher in pts with ESR1 mutation (respectively, P = 0.0055 and P = 0.0208). CA15.3 and ctDNA yield were significantly higher in pts with number of metastatic sites ≥ 3, (respectively, P = 0.0164, and P = 0.0239), while number of metastatic sites ≥ 3 and number of metastatic lesions ≥ 5 were significantly associated with CEA > 3.8 U/mL (respectively, P = 0.039, and P = 0.029). Presence of bone metastases was significantly associated with PIK3CA mutation (P = 0.040), while number of metastatic sites ≥ 3 was significantly associated with ESR1 mutation (P = 0.022). No association with tumor burden was observed for different ACTB DNA fragments lengths. Met_ratio > 1.5 was significantly associated with lower number of metastatic lesions (P = 0.031). Number of metastatic sites ≥ 3, high ctDNA yield and CEA were associated with worse OS (respectively P = 0.0465, P = 0.0250 and P = 0.0474), while only CEA impacted on PFS (P = 0.0097). Conclusions: In pts with luminal-like MBC, some liquid biopsy-based biomarkers (i.e., ctDNA-detected ESR1 and PIK3CA mutations, ctDNA yield) were significantly associated with the burden of disease. The potential clinical validity and utility of these results deserve to be tested in an expansion cohort.

Cationic carboxylate and thioacetate ruthenium(ii) complexes: synthesis and cytotoxic activity against anaplastic thyroid cancer cells

The cationic acetate ruthenium complex [Ru(η1-OAc)(CO)(dppb)(phen)]OAc (1) is easily prepared in 83% yield from [Ru(η1-OAc)(η2-OAc)(CO)(dppb)] (dppb = 1,4-bis(diphenylphosphino)butane) and 1,10-phenanthroline (phen) in MeOH. The derivative 1 undergoes easy substitution of the coordinated acetate by reaction with NaOPiv, KSAc, and KSCN in MeOH, affording the corresponding complexes [RuX(CO)(dppb)(phen)]X (X = OPiv, 2; SAc, 3; and NCS, 4), whereas its reaction with NaCl and NH4PF6 affords [RuCl(CO)(dppb)(phen)]PF6 (5). Carboxylate complexes 1 and 2 show high solubility in water, enabling easy exchange of the coordinated carboxylate by water and other ligands (CH3CN, glutathione). Cationic complexes 1-5, compared to Cisplatin, display a strong cell viability decrease in two human anaplastic thyroid cancer cell lines (SW1736 and 8505C), ranging from 3.10 μM to 0.09 μM EC50 values. The most active compounds 1-3 show a marked increment of apoptosis and decrease of cancer cell aggressiveness, making them promising candidates for further evaluation studies.

Plasma-Based Longitudinal Evaluation of ESR1 Epigenetic Status in Hormone Receptor-Positive HER2-Negative Metastatic Breast Cancer

Background

Endocrine therapy (ET) is the mainstay of treatment for hormone receptor-positive human epidermal growth factor receptor 2 (HER2)-negative metastatic breast cancer; however, adaptive mechanisms emerge in about 25–30% of cases through alterations in the estrogen receptor ligand-binding domain, with a consequent ligand-independent estrogen receptor activity. Epigenetic-mediated events are less known and potentially involved in alternative mechanisms of resistance. The aim of this study was to test the feasibility of estrogen receptor 1 (ESR1) epigenetic characterization through liquid biopsy and to show its potential longitudinal application for an early ET sensitivity assessment.

Methods

A cohort of 49 women with hormone receptor-positive HER2-negative MBC was prospectively enrolled and characterized through circulating tumor DNA using methylation-specific droplet digital PCR (MS-ddPCR) before treatment start (BL) and after 3 months concomitantly with computed tomography (CT) scan restaging (EV1). ESR1 epigenetic status was defined by assessing the methylation of its main promoters (promA and promB). The most established cell-free tumor DNA (ctDNA) factors associated with ET resistance [ESR1 and phosphatidylinositol-4,5-bisphosphate 3-kinase, catalytic subunit alpha (PIK3CA) mutations] were assessed through next-generation sequencing. Associations were tested through Mann–Whitney U test, matched pairs variations through Wilcoxon signed rank test, and survival was analyzed by log-rank test.

Results

The ET backbone was mainly based on aromatase inhibitors (AIs) (70.83%) in association with CDK4/6 inhibitors (93.75%). Significantly lower promA levels at baseline were observed in patients with liver metastases (P = 0.0212) and in patients with ESR1 mutations (P = 0.0091). No significant impact on PFS was observed for promA (P = 0.3777) and promB (P = 0.7455) dichotomized at the median while a ≥2-fold increase in promB or in either promA or promB at EV1 resulted in a significantly worse prognosis (respectively P = 0.0189, P = 0.0294). A significant increase at EV1 was observed for promB among patients with PIK3CA mutation (P = 0.0173). A trend was observed for promB in ESR1 wild-type patients and for promA in the ESR1 mutant subgroup.

Conclusion

The study proofed the concept of an epigenetic characterization strategy based on ctDNA and is capable of being integrated in the current clinical workflow to give useful insights on treatment sensitivity.

Critical Involvement of Calcium-Dependent Cytosolic Phospholipase A2α in Aortic Valve Interstitial Cell Calcification

The involvement of calcium-dependent cytosolic phospholipase A2α (cPLA2α) in aortic valve calcification is not exhaustively elucidated. Here, cPLA2α expression in aortic valve interstitial cell (AVIC) pro-calcific cultures simulating either metastatic or dystrophic calcification was estimated by qPCR, Western blotting, and counting of cPLA2α-immunoreactive cells, with parallel ultrastructural examination of AVIC calcific degeneration. These evaluations also involved pro-calcific AVIC cultures treated with cPLA2α inhibitor dexamethasone. cPLA2α over-expression resulted for both types of pro-calcific AVIC cultures. Compared to controls, enzyme content was found to increase by up to 300% and 186% in metastatic and dystrophic calcification-like cultures, respectively. Increases in mRNA amounts were also observed, although they were not as striking as those in enzyme content. Moreover, cPLA2α increases were time-dependent and strictly associated with mineralization progression. Conversely, drastically lower levels of enzyme content resulted for the pro-calcific AVIC cultures supplemented with dexamethasone. In particular, cPLA2α amounts were found to decrease by almost 88% and 48% in metastatic and dystrophic calcification-like cultures, respectively, with mRNA amounts showing a similar trend. Interestingly, these drastic decreases in cPLA2α amounts were paralleled by drastic decreases in mineralization degrees, as revealed ultrastructurally. In conclusion, cPLA2α may be regarded as a crucial co-factor contributing to AVIC mineralization in vitro, thus being an attractive potential target for designing novel therapeutic strategies aimed to counteract onset or progression of calcific aortic valve diseases.

BAZ1B is a candidate gene responsible for hypothyroidism in Williams syndrome

Williams syndrome (WS) is a rare neurodevelopmental disorder associated to a hemizygous deletion of 28 genes located on chromosome 7q11.23. WS affected subjects frequently suffer from several endocrine abnormalities including hypothyroidism due to defects in thyroid morphology. To date, several genes involved in thyroid dysgenesis have been identified, nonetheless, none of them is located in the 7q11.23 region. Thus, the hypothyroidism-linked molecular features in WS are not yet known. In this study we focused on one of the WS deleted gene, BAZ1B, demonstrating that its downregulation in thyroid cells leads to cell viability and survival decrement. Taking together, our results show that BAZ1B could be the mainly responsible for thyroid defects observed in some of WS patients and that these alterations are activated by PTEN-mediated mechanisms.

Tacrolimus Therapeutic Drug Monitoring in Stable Kidney Transplantation and Individuation of CYP3A5 Genotype

The posology of tacrolimus (TAC) is usually guided by its therapeutic drug monitoring. Some patients reach target concentrations (CTs) quickly, others more slowly. In a retrospective study, 20 kidney transplant recipients were included (mean age, 50.7 ± 14.1 years; weight 64.0 ± 14.2 kg; patients clinically stable for over a year). We studied cytochrome CYP3A5 genotype, in particular CYP3A5 6986A>G, the most important polymorphism related to the metabolism of TAC (wild genotype CYP3A5 *1 genotype, and CYP3A5 *3 variants). One year after transplantation, the CTs were 5.0 to 8.0 ng/mL. The patients were divided into group A (TAC doses < 6.0 mg/d) and group B (TAC doses > 6.0 mg/d). All were tested for the CYP3A5 gene sequence to characterize their polymorphism. Patients with CYP3A5 *1/*1 and *1/*3 were extensive metabolizers, and those with CYP3A5 *3/*3 were poor metabolizers. In group A and group B, the average TAC doses at the time of therapeutic drug monitoring were 3.0 ± 1.4 ng/mL (0.05 ± 0.03 mg/kg) and 12.8 ± 3.7 ng/mL (0.2 ± 0.1 mg/kg), respectively (P < .001). Group A was the poor metabolizers genotype, while in group B, the extensive metabolizers genotype was present. Patients with the CYP3A5 *1/*1 or *1/*3 genotype required 1.5 to 2 times higher doses than patients *3/*3 to reach CT. This genetic test allows clinicians to know, before the kidney transplant, the patient's TAC metabolism pattern and then to optimize the drug exposure.

The HuR CMLD-2 inhibitor exhibits antitumor effects via MAD2 downregulation in thyroid cancer cells

Hu antigen R (HuR) is indeed one of the most studied RNA-binding protein (RBP) since its fundamental role both in tumorigenesis and cancer progression. For this reason, downregulation in HuR protein levels or inhibition of HuR biological function are, nowadays, attractive goals in cancer research. Here, we examined the antitumor effects of CMLD-2 in four thyroid cancer cell lines (SW1736, 8505 C, BCPAP and K1). Indeed, CMLD-2 competitively binds HuR protein disrupting its interaction with RNA-targets. 35 μM CLMD-2 produced a significant downregulation in thyroid cancer cell viability, coupled to an increase in apoptosis. Moreover, CMLD-2 treatment hindered both migration and colony formation ability. MAD2 is a microtubules-associated protein known to be greatly overexpressed in cancer and correlating with tumor aggressiveness. Furthermore, MAD2 is known to be a HuR target. CMLD-2 treatment induced a strong MAD2 downregulation and rescue experiments depicted it as a key effector in HuR-mediated in cancer. Altogether, these data contributed to foster HuR inhibition as valid antineoplastic treatment in thyroid cancer, highlighting MAD2 as a novel therapeutic target.

Human telomerase reverse transcriptase in papillary thyroid cancer: gene expression, effects of silencing and regulation by BET inhibitors in thyroid cancer cells

PURPOSE

Mutations in TERT promoter have been detected in the more aggressive papillary thyroid cancers (PTCs). To elucidate the role of TERT as an eligible molecular target in these tumors, the expression of hTERT was analyzed in a series of PTCs and the effects of both pharmacological and RNA-interference-induced hTERT silencing were investigated in two human PTC cell lines (K1 and BCPAP).

METHODS

The expression levels of hTERT mRNA and protein were evaluated by real-time PCR and western blot assays, respectively. Effects of hTERT silencing on PTC cell lines were analyzed by MTT, migration and western blot assays. Pharmacological inhibition of hTERT was performed using two bromodomain and extra-terminal (BET) inhibitors, JQ1 and I-BET762.

RESULTS

hTERT expression results increased in 20 out of 48 PTCs, including tumors either positive or negative for the presence of hTERT promoter and/or BRAF mutations. In K1 and BCPAP cells, hTERT silencing determined a reduction in cell viability (~50% for K1 and ~70%, for BCPAP, vs control) and migration properties that were associated with a decrease of AKT phosphorylation and β-Catenin expression. Moreover, hTERT mRNA levels were down-regulated by two BET inhibitors, JQ1 and I-BET762, which at the same dosage (0.5 and 5 µM) reduced the growth of these thyroid cancer cells.

CONCLUSIONS

These findings demonstrate that hTERT may represent an excellent therapeutic target in subgroups of aggressive PTCs.

Successful and safe long-term treatment of cerebral aspergillosis with high-dose voriconazole guided by therapeutic drug monitoring

We report the case of a patient who had cerebral aspergillosis after otorhinolaryngologic surgery and who was successfully and safely treated with high-dose voriconazole (200 mg q6h) for more than 1 year thanks to a TDM-guided approach coupled with pharmacological review and with genotyping of CYP2C19 polymorphisms. The findings support the idea that personalized medicine based on TDM coupled with the need of avoiding drug-drug interactions may be helpful for maximizing the net benefit (probability of efficacy vs. probability of adverse events) of voriconazole in the management of long-term treatment of cerebral aspergillosis.

Genomic Deletion Involving the IMMP2L Gene in Two Cases of Autism Spectrum Disorder

Mutations/deletions of the IMMP2L gene have been associated with different cognitive/behavioral disturbances, including autism spectrum disorders (ASD). The penetrance of these defects is not complete since they often are inherited from a healthy parent. Using array-CGH in a cohort of 37 ASD patients, we found 2 subjects harboring a deletion inside the IMMP2L gene. In both cases, the IMMP2L gene deletion was inherited: from a healthy mother in one case and from a dyslectic father in the other. In the latter family, the IMMP2L deletion was also detected in the patient's brother, who showed delayed language development. In a cohort of 100 normal controls, no deletions including the IMMP2L gene were observed. However, a recent meta-analysis found no association between IMMP2L deletions and ASD. Our data would indicate that deletions involving the IMMP2L gene may contribute to the development of a subgroup of cognitive/behavioral disorders.

Anti-hTERT siRNA-Loaded Nanoparticles Block the Growth of Anaplastic Thyroid Cancer Xenograft

The high frequency of hTERT-promoting mutations and the increased expression of hTERT mRNA in anaplastic thyroid cancer (ATC) make TERT a suitable molecular target for the treatment of this lethal neoplasm. In this study, we encapsulated an anti-hTERT oligonucleotide in biocompatible nanoparticles and analyzed the effects of this novel pharmaceutical preparation in preclinical models of ATC. Biocompatible nanoparticles were obtained in an acidified aqueous solution containing chitosan, anti-hTERT oligoRNAs, and poloxamer 188 as a stabilizer. The effects of these anti-hTERT nanoparticles (Na-siTERT) were tested in vitro on ATC cell lines (CAL-62 and 8505C) and in vivo on xenograft tumors obtained by flank injection of CAL-62 cells into SCID mice. The Na-siTERT reduced the viability and migration of CAL-62 and 8505C cells after 48-hour incubation. Intravenous administration (every 48 hours for 13 days) of this encapsulated drug in mice hosting a xenograft thyroid cancer determined a great reduction in the growth of the neoplasm (about 50% vs. untreated animals or mice receiving empty nanoparticles), and decreased levels of Ki67 associated with lower hTERT expression. Moreover, the treatment resulted in minimal invasion of nearby tissues and reduced the vascularity of the xenograft tumor. No signs of toxicity appeared following this treatment. Telomere length was not modified by the Na-siTERT, indicating that the inhibitory effects of neoplasm growth were independent from the enzymatic telomerase function. These findings demonstrate the potential suitability of this anti-TERT nanoparticle formulation as a novel tool for ATC treatment. Mol Cancer Ther; 17(6); 1187-95. ©2018 AACR.

BET bromodomain inhibitor JQ1 modulates microRNA expression in thyroid cancer cells

Anaplastic thyroid carcinoma (ATC) represents the most lethal thyroid cancer sub-type, currently unresponsive to standard treatments. Recently, bromodomain and extra-terminal (BET) proteins have emerged as attractive therapeutic targets in several diseases, including cancer. In different cancer models, the anti-neoplastic activity of BET inhibitors such as JQ1, I-BET762 and I-BET151 have already been established, due to both direct and indirect effects. miRNAs are 20-22 nucleotide transcriptional regulators which play important roles in proliferation, differentiation and apoptosis. Hitherto, the relationship between JQ1 and miRNAs has not been explored. The goal of this study was to delineate JQ1-associated miRNA regulation in ATC cells. Two ATC-derived cell lines (SW1736 and 8505c) were treated with either 5 µM JQ1 or vehicle for 48 or 72 h. A non-tumorigenic thyroid cell line (Nthy-ori 3-1) was used as a control. miRNome analysis displayed a JQ1-related dysregulation of several miRNAs, 7 of which turned out to be commonly dysregulated in both cell lines at both time-points. Furthermore, miR-4516 turned out to be downregulated in both ATC cell lines, when compared to the non-tumorigenic ones and notably, JQ1 treatment in both ATC cell lines induced its upregulation, restoring, in some way, its basal expression levels. We, therefore, focused on miR-4516 expression and STAT3 levels, since it was previously predicted to be a putative target of this microRNA. Consistently, phospho-STAT3 and its target p21Waf1/Cip1 turned out to be downregulated and upregulated in both JQ1-treated ATC cell lines, respectively. Thus, our data revealed that modulation of miRNA expression is one of the multiple mechanisms of the effect of JQ1 in thyroid cancer cells.

Evaluation of somatic genomic imbalances in thyroid carcinomas of follicular origin by CGH-based approaches

Application of distinct technologies of cancer genome analysis has provided important information for the molecular characterization of several human neoplasia, including follicular cell-derived thyroid carcinoma. Among them, comparative genomic hybridization (CGH)-based procedures have been extensively applied to evaluate genomic imbalances present in these tumours, obtaining data leading to an increase in the understanding of their complexity and diversity. In this review, after a brief overview of the most commonly used CGH-based technichs, we will describe the major results deriving from the most influential studies in the literature which used this approach to investigate the genomic aberrations of thyroid cancer cells. In most studies a small number of patients have been analyzed. Deletions and duplications at different chromosomal regions were detected in all investigated cohorts. A higher number of genomic imbalances has been detected in anaplastic or poorly differentiated thyroid carcinomas compared to well differentiated ones. Limitations in the interpretation of the results, as well the potential impact in the clinical practice are discussed. Though a quite heterogeneous picture arises from results so far available, CGH array, combined with other methodologies as well as an accurate clinical management, may offer novel opportunities for a better stratification of thyroid cancer patients.

Effects of BP-14, a novel cyclin-dependent kinase inhibitor, on anaplastic thyroid cancer cells

Anaplastic thyroid carcinoma (ATC) is an extremely aggressive human malignancy characterized by a marked degree of invasiveness, absense of features of thyroid differentiation and resistance to current medical treatment. It is well known that ATCs are characterized by deregulation of genes related to cell cycle regulation, i.e., cyclin-dependent kinases (CDKs) and endogenous cyclin-dependent kinase inhibitors (CDKIs). Therefore, in the present study, the effect of a novel exogenous cyclin-dependent kinase inhibitor, BP-14, was investigated in three human ATC cell lines. The ATC-derived cell lines FRO, SW1736 and 8505C were treated with BP-14 alone or in combination with the mTOR inhibitor everolimus. In all ATC cell lines, treatment with BP-14 decreased cell viability and, in two of them, BP-14 modified expression of genes involved in epithelial-mesenchymal transition. Thus, our data indicate that BP-14 is a potential new compound effective against ATC. Combined treatment with BP-14 and the mTOR inhibitor everolimus had a strong synergistic effect on cell viability in all three cell lines, suggesting that the combined used of CDK and mTOR inhibitors may be a useful strategy for ATC treatment.

Synergy between HDAC and PARP Inhibitors on Proliferation of a Human Anaplastic Thyroid Cancer-Derived Cell Line

Anaplastic thyroid carcinoma (ATC) is a very aggressive human malignancy, having a marked degree of invasiveness and no features of thyroid differentiation. It is known that either HDAC inhibitors or PARP inhibitors have antiproliferative effects on thyroid cancer cells. Therefore, in this study the possible synergy between the two types of compounds has been investigated. The ATC-derived cell line SW1736 has been treated with the HDAC inhibitor suberoylanilide hydroxamic acid (SAHA) and the PARP inhibitor PJ34, alone or in combination. In terms of cell viability, the combination index value was always lower than 1 at various tested dosages, indicating, therefore, synergy in a wide range of doses for both compounds. Synergy was also observed in induction of apoptosis. In terms of thyroid-specific gene expression, synergy was observed for TSHR mRNA levels but not for NIS, TTF1, TTF2, and PAX8 mRNA levels. Altogether, these data suggest that the combined use of HDAC and PARP inhibitors may be a useful strategy for treatment of ATC.

Racemic synthesis and solid phase peptide synthesis application of the chimeric valine/leucine derivative 2-amino-3,3,4-trimethyl-pentanoic acid

The synthesis of non natural amino acid 2-amino-3,3,4-trimethyl-pentanoic acid (Ipv) ready for solid phase peptide synthesis has been developed. Copper (I) chloride Michael addition, followed by a Curtius rearrangement are the key steps for the lpv synthesis. The racemic valine/leucine chimeric amino acid was then successfully inserted in position 5 of neuropeptide S (NPS) and the diastereomeric mixture separated by reverse phase HPLC. The two diastereomeric NPS derivatives were tested for intracellular calcium mobilization using HEK293 cells stably expressing the mouse NPS receptor where they behaved as partial agonist and pure antagonist.

Glomerular clusterin is associated with PKC-alpha/beta regulation and good outcome of membranous glomerulonephritis in humans

Mechanisms for human membranous glomerulonephritis (MGN) remain elusive. Most up-to-date concepts still rely on the rat model of Passive Heymann Nephritis that derives from an autoimmune response to glomerular megalin, with complement activation and membrane attack complex assembly. Clusterin has been reported as a megalin ligand in immunodeposits, although its role has not been clarified. We studied renal biopsies of 60 MGN patients by immunohistochemistry utilizing antibodies against clusterin, C5b-9, and phosphorylated-protien kinase C (PKC) isoforms (pPKC). In vitro experiments were performed to investigate the role of clusterin during podocyte damage by MGN serum and define clusterin binding to human podocytes, where megalin is known to be absent. Clusterin, C5b-9, and pPKC-alpha/beta showed highly variable glomerular staining, where high clusterin profiles were inversely correlated to C5b-9 and PKC-alpha/beta expression (P=0.029), and co-localized with the low-density lipoprotein receptor (LDL-R). Glomerular clusterin emerged as the single factor influencing proteinuria at multivariate analysis and was associated with a reduction of proteinuria after a follow-up of 1.5 years (-88.1%, P=0.027). Incubation of podocytes with MGN sera determined strong upregulation of pPKC-alpha/beta that was reverted by pre-incubation with clusterin, serum de-complementation, or protein-A treatment. Preliminary in vitro experiments showed podocyte binding of biotinilated clusterin, co-localization with LDL-R and specific binding inhibition with anti-LDL-R antibodies and with specific ligands. These data suggest a central role for glomerular clusterin in MGN as a modulator of inflammation that potentially influences the clinical outcome. Binding of clusterin to the LDL-R might offer an interpretative key for the pathogenesis of MGN in humans.

ANCA-positive periaortic vasculitis: does it fall within the spectrum of vasculitis?

Retroperitoneal fibrosis (RPF) is a disease of unknown aetiology that has sometimes been reported in association with connective tissue disorders and systemic vasculitis. We report here two cases of antineutrophil cytoplasmic antibody (ANCA)-positive RPF showing clinical evidence of rapidly progressive glomerulonephritis. Although treatment with prednisone and cyclophosphamide led to a remission of RPF in both cases, renal function was restored in only one patient and the other progressed to chronic renal failure. The paper reviews the literature concerning ANCA-positive RPF and discusses the relationship between ANCA-positive vasculitis and RPF.

Interferon-alpha in combination with ribavirin as initial treatment for hepatitis C virus-associated cryoglobulinemic membranoproliferative glomerulonephritis

Mixed cryoglobulinemia (MC) and glomerulonephritis are the most important extrahepatic manifestations of chronic hepatitis C virus (HCV) infection. In HCV-infected patients with MC, renal involvement worsens the overall prognosis because of a high incidence of infection or cardiovascular disease. The relationship between MC and HCV infection has prompted the use of antiviral therapy. Two patients with chronic HCV infection, type-II MC and membranoproliferative glomerulonephritis (MPGN), presenting as nephrotic syndrome were treated with interferon (IFN)-alpha (3 MU 3 times per week) and ribavirin (15 mg/kg daily) for 6 months. Laboratory tests included measurement of anti-HCV antibodies, HCV RNA, and HCV genotyping, and characterization of circulating cryoglobulins. A pretreatment renal biopsy was performed, and the histopathologic lesions were scored according to the index of disease activity. Viremia and cryoglobulinemia were suppressed in both patients. However, a complete remission of proteinuria was observed in 1 patient only. The evaluation of the renal biopsy specimens revealed a mild MPGN (activity score: 5/24) in the patient with remission of proteinuria and a severe MPGN (activity score: 15/24) in the patient who maintained a nephrotic-range proteinuria. Although a fully satisfactory treatment is not yet available, we feel that a reasonable therapeutic strategy for HCV-infected patients with MC nephritis could be as follows: (1) antiviral treatment alone for patients with a low-grade kidney involvement, and (2) a short-term course of steroids and cytotoxic drugs followed by antiviral therapy for acute exacerbations and/or rapidly progressive GN.

Fluorescent in situ hybridisation on tissue sections: a quantitative approach with confocal laser scanning microscopy

The use of fluorescent detection methods in association with digital microscopy technologies is an innovative approach for tissue localisation of messenger RNA. The success of such methods relies on the tissue preservation, local availability of the probe and on the existence of high resolution tridimensional analysis systems. Cryostatic sections, mild denaturation, short oligonucleotide probes (20mer) and confocal laser scanning microscopy allow the fulfillment of all these conditions avoiding photobleaching and tissue autofluorescence. In this paper, we describe in detail a method for in situ hybridisation set up with digoxigenin-coupled oligonucleotide complementary to beta-actin mRNA as a probe and an anti-hapten fluorescent antibody as second step for detecting specific hybridisation. Fluorescence was analysed by means of a confocal laser scanning microscope (CLSM) that provides images with low out-of-focus blurring also with relatively low numerical aperture (NA) objectives. We propose also an easy method to perform semi-quantitative thresholding analysis which allows to discriminate between background and specific signal.

Hypertension as an etiopathological factor in the development of cerebral atrophy in hemodialyzed patients

Twenty-five patients on long-term regular hemodialysis treatment (RDT) at our dialysis unit who underwent diagnostic cerebral computed tomography (CCT) participated in a study aimed at clarifying the pathogenesis of cerebral atrophy occasionally found at their original scan. The upper age limit was 55 years to exclude the physiological involutive brain changes occurring with age. Cerebral atrophy (CA), as defined morphologically (enlargement of cerebral sulci or an increased Evan's Index), was detected in all cases. Seventeen patients underwent magnetic resonance imaging (MRI) to define possible white matter changes more accurately. No significant correlation was found between the degree of atrophy and the following uremia-altered hematoseric parameters: creatinine, hematocrit, cholesterol, triglyceridemia, albumin, PTH, calcium, inorganic phosphate. There was no correlation between degree of atrophy and number of months the patients had been on RDT or time that passed between the finding of a creatinine clearance <30 ml/min and the start of RDT. Very high correlations were found between the degree of CA and predialytic blood pressure values, and between CA and the duration of hypertension (n = 13, r = 0.66, p < 0.013). Thus, hypertension seems to be an early cause of cerebral parenchymal damage in RDT patients, and should be promptly corrected.

[Physiopathology, clinical aspects and prevention of renal insufficiency caused by contrast media]

Contrast-media associated nephropathy (CMAN) consists in a sudden impairment of glomerular filtration rate following exposure to radiographic contrast materials. Damage may be limited to an asymptomatic mild increase of blood creatinine, or reach the highest levels of nitrogen retention compatible with acute renal failure. Some preexisting clinical conditions or pathologies may lead to CMAN: not only renal insufficiency, diabetes mellitus, multiple myeloma, congestive heart failure and severe hypertension, but also simple dehydration and a growing series of immunologic diseases are recognized as predisposing condition. The exact mechanism responsible for renal injury is still doubtful but recently animal models have shown substantial ischemic changes that may be added to the traditional presumed pathogenesis of direct tubular toxicity and intra-tubular obstruction. As renal ischemia stimulates both endogenous vasoconstrictor and vasodilator substances, it is now supposed that CMAN acts similarly to non-steroidal anti-inflammatory agents, selectively inhibiting the vasodilatory prostaglandin phase and therefore causing a derangement of the physiologic vasoconstriction/vasodilatation balance of renal circulation. The role of oxygen free radicals to contribute to renal dysfunction is considered. Low osmolality non ionic contrast media when compared to conventional high osmolality ionic contrast media have reduced but not eliminated CMAN. Simple but effective lines of prevention include the previous selection of patients predisposed to CMAN for concomitant pathology, suspension of FANS or any other recognized nephrotoxic substance, the least amount of contrast media compatible with radiologic visualization of the patient's problem, careful hydration of the patient before contrast injection and sustained diuresis afterwards. The usefulness of pre-treatment with Ca-channel blockers or atrial natriuretic factors remains sub judice.

[Treatment of arterial hypertension in diabetic nephropathy. Certainties and hypotheses]

Clinical observation has long emphasized the importance of arterial hypertension in the course of diabetic nephropathy and recent studies suggest that hypertension might play a decisive pathogenetic role in the course of the disease, hence the necessity of correcting the hypertension of diabetic patients has by now been universally accepted. There is, however, still some uncertainty concerning the usefulness of acting preventively on so-called microhypertension; in other words, whether early antihypertensive drug treatment can prevent diabetic nephropathy. This paper discusses the criteria to be followed in the choice of antihypertensive medication during diabetic nephropathy giving special attention to pathophysiological considerations. Moreover, it also discusses the effects of antihypertensive drugs currently regarded as first-choice agents, i.e. calcium antagonists and the angiotensin converting enzyme inhibitors, on intrarenal hemodynamics.

Renal effects of captopril, indomethacin and nifedipine in nephrotic patients after an oral protein load

BACKGROUND

In this study we investigated whether the increase in proteinuria induced by an oral protein load may be prevented by the angiotensin-converting enzyme inhibitor (ACEI) captopril in patients with nephrotic syndrome, and whether the effects of captopril on renal haemodynamics and/or glomerular selectivity are comparable to those obtained with the nonsteroidal anti-inflammatory drug (NSAID) indomethacin and the calcium-channel blocker (CaCB) nifedipine.

METHODS

Twelve subjects underwent the following treatments: (1) low-protein meal (0.2 g protein/kg body wt), (2) high-protein meal (1.3 g protein/kg body wt), (3) high-protein meal plus oral captopril (50 mg), (4) high-protein meal plus oral nifedipine (10 mg), (5) high-protein meal plus oral indomethacin (50 mg). Urine and blood samples were obtained after meals and tested for total protein, immunoglobulin G and albumin. GFR and renal plasma flow (RPF) were calculated from iothalamate and p-aminohippuric acid clearances respectively.

RESULTS

Mean arterial pressure decreased significantly after both captopril (-4%, P = 0.001) and nifedipine (-5%, P = 0.0019). Compared with the low-protein meal, mean values of GFR and RPF increased significantly after the high-protein meal alone (+21%, P = 0.0002; +10%, P = 0.0491 respectively), and after captopril (+18%, P = 0.0025; +24%, P = 0.0034 respectively) or nifedipine administration (+30%, P = 0.0001; +21%, P = 0.0036 respectively), whereas they remained unchanged after the high-protein meal plus indomethacin administration. FF did not change significantly under the five experimental conditions. The increase in urinary protein excretion induced by the meat load (total protein +18%, P = 0.0102; albumin +26%, P = 0.0316; IgG +28%, P = 0.0203) was entirely blocked by both captopril and indomethacin, whereas it was further increased by nifedipine administration.

CONCLUSIONS

Both captopril and indomethacin, but not nifedipine, are able to prevent the increase in urinary protein excretion rate following a meat meal. The antiproteinuric effect of captopril is comparable to that of indomethacin, but the renal haemodynamic changes induced by these drugs differ considerably, because the filtration capacity and the renal functional reserve were preserved by captopril and decreased by indomethacin. The reduction in systemic blood pressure following administration of both captopril and nifedipine does not account for changes in proteinuria, since, with a similar degree of blood pressure lowering, urinary protein excretion is reduced by captopril and increased by nifedipine.

Progression of cerebral atrophy in patients on regular hemodialysis treatment: long-term follow-up with cerebral computed tomography

Fifteen patients (10 males, 5 females) on regular hemodialysis treatment (average age 43.6 +/- 4.0 years, average time on dialysis 100.7 +/- 62.8 months) underwent cerebral computed tomography between 1981 and 1984. Ten patients showed mild cerebral atrophy (CA) on the basis of cortical sulci exceeding 3 mm in breadth and an Evans ratio exceeding 0.31, for a total of 14 degrees of CA (mean 0.9 +/- 1). The same 15 patients underwent a second cerebral computed tomography during 1991/92 (101 +/- 23.7 months later). At that time, the patients exhibited a degree of CA of 2.6 +/- 1.4, for a total of 39 degrees with an overall increase of 25 degrees. Since CA is not detected before the age of 55 years in the normal population, we conclude that the CA in this patient group can only be attributed to uremia-related pathology and that it tends to worsen as regular hemodialysis treatment continues. Nevertheless, no evident cognitive, affective, or behavioural changes were verified in these patients. To our knowledge, this is the first presentation of radiologically documented progression of CA in the same patient population over time.

Significance of albuminuria in the follow-up of acute poststreptococcal glomerulonephritis

The present study was aimed at assessing the diagnostic value of urinary albumin (uA) excretion rate in the long-term follow-up of patients suffering from acute post-streptococcal glomerulonephritis (APSGN). 26 patients, who had presented primarily with nephritic syndrome and showing increased uA without a concomitant rise in total proteinuria (uTP) were followed-up for 131 months on average (range 36-288). At the last check, 14 patients did not show urinary abnormalities, 9 had a persistent increase in uA, 1 increased uTP and 2 renal insufficiency. Urinary and clinical signs of the disease were not seen during observation periods prolonged for 79 months on average (range 20-156) after normalization of uA. No pathological findings were remarked in biopsy specimens obtained in 3 patients when uA was normalized; in contrast, when both uTP and uA (12 cases) or when isolated uA (14 cases) were increased a pattern of diffuse mesangial proliferative glomerulonephritis was constantly observed. These results indicate that the abnormal uA excretion rate during long-term follow-up of APSGN allows to identify a subset of patients with persistent renal disease; conversely, the occurrence of normal uA seems to point to a good diagnostic and prognostic significance.

[The treatment of arterial hypertension in diabetes mellitus. Choices and problems]

Recent studies indicate that arterial hypertension in diabetes mellitus is a paramount pathogenetic step in the evolution and acceleration of diabetic macro- and microangiopathy and in particular in the development of nephropathy and uremia. This paper deals with the clinical problems of antihypertensive treatment in diabetic patients and discusses the antihypertensive repertory with the aim at determining the best drug choice in the individual case. In the light of our present pathophysiologic knowledges of the intrarenal effects of the various classes of antihypertensive drugs the possibility of preventing diabetic nephropathy is discussed.

A diffusion immunogold procedure for accurate ultrastructural investigation of renal cell membrane epitopes

A role for renal antigenic targets has been supposed and sometimes convincingly demonstrated in the development of various types of experimental glomerulonephritides. In this report we describe a reliable protocol for accurate ultrastructural investigation of antigens on the renal cell surface by means of a pre-embedding technique associated with colloidal gold staining. Sprague-Dawley rats were injected with a monoclonal antibody specific for a 90-kD cell membrane glycoprotein and killed 12 or 48 h later; after prefixation, renal fragments were cryoprotected and snap-frozen. Cryostat sections were incubated with a 5-nm colloidal gold-goat antimouse antibody, postfixed in osmium tetroxide reduced with potassium ferrocyanide and embedded in Durcupan ACM. At the glomerular level, gold granules were localized on the endothelial cell surface. In the proximal tubules uniform labelling was noticed on the brush border microvilli, followed by later marking of the basolateral membranes. By this pre-embedding immunogold method we obtained suitable histological preservation and fine resolution of the cell membrane immunoreactive sites. This procedure represents a useful tool for ultrastructural studies on the interaction of circulating antibodies with renal cell surface antigens.

Late recurrence of systemic vasculitis after kidney transplantation involving the kidney allograft

A patient is described in whom a recurrence of vasculitis was observed in the kidney allograft six years after transplantation and one year after withdrawal of corticosteroid therapy. This case shows that systemic vasculitis may recur at any time after transplantation which implies a continuous and careful monitoring of these patients.