Raffaella Carletti

Prevention of diabetic nephropathy by compound 21, selective agonist of angiotensin type 2 receptors, in Zucker diabetic fatty rats

The aim of this study was to evaluate the effect of compound 21 (C21), a selective AT2 receptor agonist, on diabetic nephropathy and the potential additive effect of C21, when associated with losartan treatment, on the development of albuminuria and renal fibrosis in Zucker diabetic fatty (ZDF) rats. The experiments lasted 15 wk (from 5 to 20 wk of age) and were performed in 40 ZDF rats and 12 control lean rats. ZDF rats were divided into 4 groups: 1) 9 rats were treated with losartan; 2) 10 rats were treated with C21; 3) 9 rats were treated with losartan plus C21; and 4) 12 rats were maintained without any treatment. ZDF rats showed an increase in blood glucose level, albuminuria, renal fibrosis, macrophage infiltration, and TNF-α expression and a reduction of glomerular nephrin expression compared with control lean rats. C21 treatment reduced renal glomerular, tubulointerstitial, and perivascular fibrosis, and macrophage infiltration and TNF-α expression in ZDF rats. C21 treatment caused a decrease in albuminuria in ZDF rats up to 11 wk of age. Losartan decreased macrophage infiltration, TNF-α expression, and renal glomerular and perivascular fibrosis, restored glomerular nephrin expression, but did not affect tubulointerstitial fibrosis. Losartan treatment caused a decrease in albuminuria in ZDF rats up to 15 wk of age. At the end of the protocol, only the combination of C21 plus losartan significantly reduced albuminuria in ZDF rats. These data demonstrate that C21 has beneficial effects on diabetic nephropathy, suggesting the combination of C21 and losartan as a novel pharmacological tool to slow the progression of nephropathy in type II diabetes.

The rationale for liquid biopsy in colorectal cancer: a focus on circulating tumor cells

Capturing circulating tumor cells (CTCs) and/or circulating tumor DNA from blood, which represents a precious source of biological material derived from both primary and metastatic tumors, has been named a ‘liquid biopsy’. While the circulating tumor DNA might be more representative of the bulk of the metastatic tumor, CTCs are thought to reflect more of the metastases-initiating cells. Consequently, a liquid biopsy made of tumor cells and tumor DNA that is able to track cancer evolution, as a fingerprint of the patient’s individual tumor, and is easy to perform at every stage of the disease course, sounds attractive. This article mainly focuses on the applications of CTCs to track tumor dynamics in real time using colorectal cancer as a model system. The analysis of viable CTCs at DNA, RNA and protein levels, as well as their expansion in vitro, may allow deep investigation of the features of metastases-initiating cells.

Different regulation of miR‐29a‐3p in glomeruli and tubules in an experimental model of angiotensin II‐dependent hypertension: potential role in renal fibrosis

The aim of this study was to evaluate the role of the angiotensin II (Ang II) induced‐differential miRNA expression in renal glomerular and tubulo‐interstitial fibrosis in an experimental model of Ang II‐dependent hypertension. To clarify this issue, Sprague Dawley rats were treated with Ang II (200 ng/kg per minute, n = 15) or physiological saline (n = 14) for 4 weeks. Systolic blood pressure and albuminuria were measured every 2 weeks. At the end of the experimental period, renal glomerular and tubulo‐interstitial fibrosis was evaluated by histomorphometric analysis, after Sirius‐Red and Massons trichrome staining. Ang II increased systolic blood pressure (P < 0.0001), albuminuria (P < 0.01) and both glomerular and tubulo‐interstitial fibrosis (P < 0.01). Using laser capture microdissection and miRNA microarray analysis this study showed that miR‐29a‐3p was down‐regulated in renal tubules and up‐regulated in glomeruli. Real‐time polymerase chain reaction (PCR) experiments confirmed in Ang II‐treated rats a down‐regulation of miR‐29a‐3p in tubules (P < 0.01), while no significant changes were observed in glomeruli. Matrix metalloproteinase‐2 (MMP‐2) was identified as putative miR‐29a‐3p target (by TargetScan, miRanda, Tarbase software) and functionally confirmed by luciferase activity assay. These data demonstrate that the effects of Ang II on miR‐29a‐3p expression in renal tubules is different from the one exerted in the glomeruli and that miR‐29a‐3p targets MMP‐2. These results suggest that the development of renal fibrosis at glomerular and tubulo‐interstitial level depends on different molecular mechanisms.

Angiotensin Type-2 (AT-2)-Receptor activation reduces renal fibrosis in cyclosporine nephropathy: Evidence for blood-pressure independent effect.

Compound 21 (C21), selective agonist of angiotensin type-2 (AT-2) receptors, shows anti-inflammatory effects in experimental models of hypertension and nephroprotection in diabetes. The aim of the present study was to evaluate the effects of C21 in cyclosporine nephropathy, which is characterized mainly by tubulo-interstitial fibrosis. Ten days before and during the experimental periods, low-salt diet was administered to Sprague–Dawley rats. Cyclosporine-A (CsA; 15 mg/kg per day, intraperitoneal injection) and CsA plus C21 (0.3 mg/kg per day, intraperitoneal injection) were administered for 1 and 4 weeks. Control groups were left without any treatment. Blood pressure (plethysmographic method) and 24 h urinary albumin excretion were measured once a week. At the end of the experimental protocols, the kidneys were excised for histomorphometric analysis of renal fibrosis and for immunohistochemical evaluation of inflammatory infiltrates and type I and type IV collagen expression. After 1 and 4 weeks, the rats treated with CsA showed a significant increase (P<0.01) in blood pressure, no significant changes in urinary albumin excretion and a significant increase (P<0.01) in glomerular and tubulo-interstitial fibrosis and inflammatory infiltrates as compared with the control rats. Treatment with C21 did not modify the CsA dependent increase of blood pressure, which was higher than in control rats, but after 4 weeks of treatment significantly reduced (P<0.01) glomerular and tubulo-interstitial fibrosis, type 1 collagen expression and macrophage infiltration, as compared with rats treated with cyclosporine. The administration of C21 showed a protective effect on cyclosporine nephropathy, decreasing renal fibrosis and macrophage infiltration. These data suggest that C21 may counteract tubulo-interstitial fibrosis, the most potent predictor of the progression of renal diseases.

The Eisenmenger malformation: a morphologic study.

We studied 11 autopsied cases of the Eisenmenger malformation, comparing the findings with 11 hearts with intact ventricular septal structures, and nine hearts having perimembranous ventricular septal defects in the absence of aortic overriding. We found variable lengths for the subpulmonary infundibulum in the hearts with Eisenmenger defects. It was well developed in three hearts, of intermediate length in seven, and very short in one of the specimens. The muscular outlet septum was also of variable length compared with the free-standing subpulmonary infundibular sleeve. Except for one, all hearts had fibrous continuity between the aortic and tricuspid valvar leaflets, such that the ventricular septal defect was then perimembranous. In the remaining case, there was a completely subaortic muscular infundibulum, with the ventricular septal defect showing only muscular borders. The medial papillary muscle was absent in the majority of cases, but was well formed in three hearts, all with relatively short muscular outlet septums. We identified mild, intermediate, and severe degrees of rightward rotation of the aortic valve, and these findings correlated with the extent of aortic valvar overriding. In nine of the 11 hearts, the ventriculo-arterial connections were concordant, but there was double-outlet from the right ventricle in the other two specimens. Based on our anatomic and morphometric observations, we conclude that the hearts we have defined as having Eisenmenger defects show marked individual variation in their specific phenotypic anatomy.

Whole-exome analysis in osteosarcoma to identify a personalized therapy

Osteosarcoma is the most common pediatric primary non-hematopoietic bone tumor. Survival of these young patients is related to the response to chemotherapy and development of metastases. Despite many advances in cancer research, chemotherapy regimens for osteosarcoma are still based on non-selective cytotoxic drugs. It is essential to investigate new specific molecular therapies for osteosarcoma to increase the survival rate of these patients. We performed exomic sequence analyses of 8 diagnostic biopsies of patients with conventional high grade osteosarcoma to advance our understanding of their genetic underpinnings and to correlate the genetic alteration with the clinical and pathological features of each patient to identify a personalized therapy.We identified 18,275 somatic variations in 8,247 genes and we found three mutated genes in 7/8 (87%) samples (KIF1B, NEB and KMT2C). KMT2C showed the highest number of variations; it is an important component of a histone H3 lysine 4 methyltransferase complex and it is one of the histone modifiers previously implicated in carcinogenesis, never studied in osteosarcoma. Moreover, we found a group of 15 genes that showed variations only in patients that did not respond to therapy and developed metastasis and some of these genes are involved in carcinogenesis and tumor progression in other tumors.These data could offer the opportunity to get a key molecular target to identify possible new strategies for early diagnosis and new therapeutic approaches for osteosarcoma and to provide a tailored treatment for each patient based on their genetic profile.Osteosarcoma is the most common pediatric primary non-hematopoietic bone tumor. Survival of these young patients is related to the response to chemotherapy and development of metastases. Despite many advances in cancer research, chemotherapy regimens for osteosarcoma are still based on non-selective cytotoxic drugs. It is essential to investigate new specific molecular therapies for osteosarcoma to increase the survival rate of these patients. We performed exomic sequence analyses of 8 diagnostic biopsies of patients with conventional high grade osteosarcoma to advance our understanding of their genetic underpinnings and to correlate the genetic alteration with the clinical and pathological features of each patient to identify a personalized therapy. We identified 18,275 somatic variations in 8,247 genes and we found three mutated genes in 7/8 (87%) samples (KIF1B, NEB and KMT2C). KMT2C showed the highest number of variations; it is an important component of a histone H3 lysine 4 methyltransferase complex and it is one of the histone modifiers previously implicated in carcinogenesis, never studied in osteosarcoma. Moreover, we found a group of 15 genes that showed variations only in patients that did not respond to therapy and developed metastasis and some of these genes are involved in carcinogenesis and tumor progression in other tumors. These data could offer the opportunity to get a key molecular target to identify possible new strategies for early diagnosis and new therapeutic approaches for osteosarcoma and to provide a tailored treatment for each patient based on their genetic profile.

Clinical significance of epithelial‐to‐mesenchymal transition in laryngeal carcinoma: its role in the different subsites

During epithelial‐to‐mesenchymal transition, cancer cells lose adhesion capacity gaining migratory properties. The role of the process on prognosis has been evaluated in 50 cases of laryngeal carcinoma.

Multicolor flow cytometric analysis of TLR2 and TLR9 expression and function in NK cells from patients with ANCA-associated vasculitis

The primary objective of this study was to provide an assessment of NK cells in patients with ANCA‐associated vasculitis (AAV).

Subtotal resection of vestibular schwannoma: Evaluation with Ki-67 measurement, magnetic resonance imaging, and long-term observation

Purpose The aim of this study was to compare the postoperative clinical and radiological data of patients with vestibular schwannomas who were initially managed by near total resection (NTR) or subtotal resection (STR). The Ki-67 analysis results were compared with tumor regrowth to determine the presence of a correlation between this proliferative index and postoperative tumor regrowth. Study Design Seventeen adult patients (7 male, 10 female) were retrospectively reviewed. Nine (52.9%) and eight (47.1%) patients underwent NTR and STR, respectively. Postoperative clinical and radiological data associated with vestibular schwannoma growth were compared with the Ki-67 immunohistochemical analysis results. Results Evidence of clinically significant regrowth was observed in four (23.5%) patients. Patients who underwent NTR had a lower rate/incidence of tumor regrowth than did patients who underwent STR. Patients with a higher Ki-67 index had the highest tumor regrowth rates. Conclusions Our study indicates that assessment of the Ki-67 index may be useful for determining the probability of regrowth of vestibular schwannomas when only partial removal is accomplished.

Correction: The nuclear-cytoplasmic trafficking of a chromatin-modifying and remodelling protein (KMT2C), in osteosarcoma

[This corrects the article DOI: 10.18632/oncotarget.25755.].