Drug-Repurposing Strategy for Dimethyl Fumarate

In the area of drug discovery, repurposing strategies represent an approach to discover new uses of approved drugs besides their original indications. We used this approach to investigate the effects of dimethyl fumarate (DMF), a drug approved for relapsing-remitting multiple sclerosis and psoriasis treatment, on early injury associated with diabetic retinopathy (DR). We used an in vivo streptozotocin (STZ)-induced diabetic rat model. Diabetes was induced by a single injection of STZ in rats, and after 1 week, a group of animals was treated with a daily intraperitoneal injection of DMF or a vehicle. Three weeks after diabetes induction, the retinal expression levels of key enzymes involved in DR were evaluated. In particular, the biomarkers COX-2, iNOS, and HO-1 were assessed via Western blot and immunohistochemistry analysis. Diabetic rats showed a significant retinal upregulation of COX-2 and iNOS compared to the retina of normal rats (non-diabetic), and an increase in HO-1 was also observed in the STZ group. This latter result was due to a mechanism of protection elicited by the pathological condition. DMF treatment significantly induced the retinal expression of HO-1 in STZ-induced diabetic animals with a reduction in iNOS and COX-2 retinal levels. Taken together, these results suggested that DMF might be useful to counteract the inflammatory process and the oxidative response in DR. In conclusion, we believe that DMF represents a potential candidate to treat diabetic retinopathy and warrants further in vivo and clinical evaluation.

Modulatory activity of ADNP on the hypoxia‑induced angiogenic process in glioblastoma

Glioblastoma multiforme (GBM) is a brain cancer with a poor prognosis that affects adults. This is a solid tumor characterized by a high rate of cell migration and invasion. The uncontrolled cell proliferation creates hypoxic niches in the tumor mass, which leads to the overexpression of hypoxia‑inducible factors (HIFs). This induces the activation of the vascular endothelial growth factor (VEGF), which is responsible for uncontrolled neoangiogenesis. Recent studies have demonstrated the anti‑invasive effect of pituitary adenylate cyclase‑activating peptide (PACAP) in GBM. PACAP effects on the central nervous system are also mediated through the activity‑dependent neuroprotective protein (ADNP) activation. To date, no evidence exists regarding its role in GBM. Therefore, the ADNP involvement in GBM was investigated. By analyzing ADNP expression in a human GBM sample through confocal microscopy, a high ADNP immunoreactivity was detected in most glial cells and its predominant expression in hypoxic areas overexpressing HIF‑1α was highlighted. To investigate the role of ADNP on the HIF‑VEGF axis in GBM, a human U87MG GBM cell line was cultured with a hypoxic mimetic agent, deferoxamine, and cells were treated with the smallest active fragment of ADNP, known as NAP. The protein expression and distribution of HIF‑1α and VEGF was detected using western blot analysis and immunofluorescence assay. Results demonstrated that ADNP modulates the hypoxic‑angiogenic pathway in GBM cells by reducing VEGF secretion, detected through ELISA assay, as well as modulating their migration, assessed through wound healing assay. Although deeper investigation is necessary, the present study suggested that ADNP could be involved in PACAP anti‑invasive effects in GBM.

PD-1, PD-L1 and cAMP immunohistochemical expressions are associated with worse oncological outcome in patients with bladder cancer

PURPOSE

In this study, we aimed to identify prognostic factors of cancer mortality in patients who received radical cystectomy and to identify genomic alterations in a sub-cohort of patients with locally advanced (pT3-4) and/or positive lymph nodes bladder cancer (BC).

METHODS

We collected 101 BC samples from 2010 to 2018 who previously received radical cystectomy. Immunohistochemical slides were evaluated for PPAR, cAMP, IMP3, Ki67, CDK4, POU5F1, Cyclin E and MDM2, p65, CD3, CD4, CD8, CD20, CD68, CD163, FOXP3, PD-1 and PD-L1 expression. We calculated a prognostic score (PS) based on the positivity to PD-1, PD-L1 and of cAMP (final score ranging from 0 to 3). DNA of each sample have been used for sequencing by NGS in a sub-cohort of 6 patients with locally advanced (pT3-4) and/or positive lymph nodes BC.

RESULTS

PD-1 ⁺ (HR [hazard ratio] 2.59; p = 0.04), PD-L1⁺ (HR = 6.46; p < 0.01) and cAMP⁺ (HR 3.04; p = 0.02) were independent predictors of cancer-specific mortality (CSM). Increase of PS (score = 0 as reference) was associated with CSM, 0.81 (p = 0.80), 4.72 (p = 0.01) and 10.51 (p < 0.0) for PS 1, 2 and 3, respectively. ERBB2 was the gene most frequently mutated.

CONCLUSION

BC exhibited heterogenous protein expression and variable genomic features. Identification of expression of PD-1, PD-L1 and cAMP could help in predicting oncological outcomes.

Insulin signaling, androgen receptor and PSMA immunohistochemical analysis by semi-automated tissue microarray in prostate cancer with diabetes (DIAMOND study)

In the last years, many studies have highlighted the hypothesis that diabetes and hyperglycemia could be relevant for prostate cancer (PC) development and progression. We aimed to identify the prognostic value of tissue expression of androgen receptor (AR), Prostate-Specific Membrane Antigen (PSMA), Ki-67, insulin receptors (IR)  α and β, insulin growth factor-1 (IGF-1) receptor, in patients with PC and to evaluate their association with diabetes. We retrospectively collected data from 360 patients who underwent radical prostatectomy for PC or surgery for benign prostatic hyperplasia (BPH), between 2010 and 2020. We constructed tissue microarray for immunohistochemistry (IHC) analysis. In the final cohort (76 BPH and 284 PC), 57 (15.8%) patients had diabetes, 17 (22.37%) in BPH and 40 (14.08%) in PC (P = 0.08). IR-α was more expressed in patients with PC compared to the BPH Group (95.96% vs 4.04%; P <0.01). We found that AR was associated with increased risk of International Society of Urological Pathology (ISUP) score ≥4 (OR: 2.2; P <0.05), higher association with Ki-67 (OR: 2.2; P <0.05) and IR-α (OR: 5.7; P <0.05); IGF-1 receptor was associated with PSMA (OR: 2.8; P <0.05), Ki-67 (OR: 3.5; P <0.05) and IR-β (OR: 5.1; P <0.05). Finally, IGF-1 receptor was predictive of ISUP ≥ 4 (OR: 16.5; P =0.017) in patients with PC and diabetes. In the present study we highlighted how prostate cancer patients have a different protein expression in the tissue. This expression, and in particular that relating to IGF-1R, is associated with greater tumor aggressiveness in those patients with diabetes. We suppose that these results are attributable to an alteration of the insulin signal which therefore determines a greater mitogenic activity that can influence tumor progression.

SRSF-1 and microvessel density immunohistochemical analysis by semi-automated tissue microarray in prostate cancer patients with diabetes (DIAMOND study)

OBJECTIVE

To study the association between insulin receptors (isoforms α and β), insulin growth factor-1 (IGF1) and serine/arginine splicing factor 1 (SRSF-1) in patients with prostate cancer (PC) and diabetes.

MATERIALS AND METHODS

We retrospectively analyzed data from 368 patients who underwent surgery for PC or benign prostatic hyperplasia (BPH) between 2010 and 2020 at the Department of Urology, University of Catania. Tissue microarray slides were constructed and they were stained for androgen receptor (AR), insulin receptor-α and -β, IGF1 (IGF1-R), Ki-67, and prostate specific membrane antigen (PSMA) expression using validated score.

RESULTS

The final cohort was represented by 100 patients with BPH and 268 with PC, with a median age of 68 years. We found that SRSF-1 expression was associated with AR (odds ratio [OR]: 1.66), PSMA (OR: 2.13), Ki-67 (OR: 5.99), insulin receptor (IR)-α (OR: 2.38), IR-β (OR: 3.48), IGF1-R (OR: 1.53), and microvascular density (MVD) was associated with PSMA (OR: 3.44), Ki-67 (OR: 2.23), IR-α (OR: 2.91), IR-β (OR: 3.02), IGF1-R (OR: 2.95), and SRSF-1 (OR: 2.21). In the sub cohort of PC patients, we found that SRSF-1 expression was associated with AR (OR: 2.34), Ki-67 (OR: 6.77), IR-α (OR: 2.7), and MVD (OR: 1.98). At the Kaplan-Meier analysis, SRSF-1⁺ patients had worse 5- and 9-year biochemical recurrence (36% and 6%) respect to SRSF-1^- (67% and 7%; p < .01) and similarly MVD⁺ patients (44% and 7%) respect to MVD^- (64% and 8%; p < .01). Restricting the analysis only in patients with PC and diabetes, we found that SRSF-1⁺ was associated with Ki-67⁺ (OR: 8.75; p < .05) and MVD⁺ (OR: 7.5; p < .05).

CONCLUSIONS

PC exhibits widespread heterogeneity in protein expression. In particular, the expressions of the SRSF-1 protein and of the MVD are associated with a worse prognosis and in particular with a greater cell proliferation. These results, although preliminary, may offer new future scientific insights with the aim of highlighting possible genetic alterations linked to a greater expression of SRSF-1 and associated with a worse prognosis.

Morphological Evidence of Telocytes in Skeletal Muscle Interstitium of Exercised and Sedentary Rodents

Skeletal muscle atrophy, resulting from states of hypokinesis or immobilization, leads to morphological, metabolic, and functional changes within the muscle tissue, a large variety of which are supported by the stromal cells populating the interstitium. Telocytes represent a recently discovered population of stromal cells, which has been increasingly identified in several human organs and appears to participate in sustaining cross-talk, promoting regenerative mechanisms and supporting differentiation of local stem cell niche. The aim of this morphologic study was to investigate the presence of Telocytes in the tibialis anterior muscle of healthy rats undergoing an endurance training protocol for either 4 weeks or 16 weeks compared to sedentary rats. Histomorphometric analysis of muscle fibers diameter revealed muscle atrophy in sedentary rats. Telocytes were identified by double-positive immunofluorescence staining for CD34/CD117 and CD34/vimentin. The results showed that Telocytes were significantly reduced in sedentary rats at 16 weeks, while rats subjected to regular exercise maintained a stable Telocytes population after 16 weeks. Understanding of the relationship between Telocytes and exercise offers new chances in the field of regenerative medicine, suggesting possible triggers for Telocytes in sarcopenia and other musculoskeletal disorders, promoting adapted physical activity and rehabilitation programmes in clinical practice.

Engineered cartilage regeneration from adipose tissue derived-mesenchymal stem cells: A morphomolecular study on osteoblast, chondrocyte and apoptosis evaluation

The poor self-repair capacity of cartilage tissue in degenerative conditions, such as osteoarthritis (OA), has prompted the development of a variety of therapeutic approaches, such as cellular therapies and tissue engineering based on the use of mesenchymal stem cells (MSCs). The aim of this study is to demonstrate, for the first time, that the chondrocytes differentiated from rat adipose tissue derived-MSCs (AMSCs), are able to constitute a morphologically and biochemically healthy hyaline cartilage after 6 weeks of culture on a Collagen Cell Carrier (CCC) scaffold. In this study we evaluated the expression of some osteoblasts (Runt-related transcription factor 2 (RUNX2) and osteocalcin), chondrocytes (collagen I, II and lubricin) and apoptosis (caspase-3) biomarkers in undifferentiated AMSCs, differentiated AMSCs in chondrocytes cultured in monolayer and AMSCs-derived chondrocytes seeded on CCC scaffolds, by different techniques such as immunohistochemistry, ELISA, Western blot and gene expression analyses. Our results showed the increased expression of collagen II and lubricin in AMSCs-derived chondrocytes cultured on CCC scaffolds, whereas the expression of collagen I, RUNX2, osteocalcin and caspase-3 resulted decreased, when compared to the controls. In conclusion, this innovative basic study could be a possible key for future therapeutic strategies for articular cartilage restoration through the use of CCC scaffolds, to reduce the morbidity from acute cartilage injuries and degenerative joint diseases.

Genetic blockade of the dopamine D3 receptor enhances hippocampal expression of PACAP and receptors and alters their cortical distribution

Dopamine D3 receptors (D3Rs) are implicated in several aspects of cognition, but their role in aversive conditioning has only been marginally uncovered. Investigations have reported that blockade of D3Rs enhances the acquisition of fear memories, a phenomenon tightly linked to the neuropeptide pituitary adenylate cyclase-activating peptide (PACAP). However, the impact of D3R ablation on the PACAPergic system in regions critical for the formation of new memories remains unexplored. To address this issue, levels of PACAP and its receptors were compared in the hippocampus and cerebral cortex (CX) of mice devoid of functional D3Rs (D3R(-/-)) and wild-types (WTs) using a series of comparative immunohistochemical and biochemical analyses. Morphometric and stereological data revealed increased hippocampal area and volume in D3R(-/-) mice, and augmented neuronal density in CA1 and CA2/3 subfields. PACAP levels were increased in the hippocampus of D3R(-/-) mice. Expression of PACAP receptors was also heightened in mutant mice. In the CX, PACAP immunoreactivity (IR), was restricted to cortical layer V in WTs, but was distributed throughout layers IV-VI in D3R(-/-) mice, along with increased mRNAs, protein concentration and staining scores. Consistently, PAC1, VPAC1 and VPAC2 IRs were variably redistributed in CX, with a general upregulation in cortical layers II-IV in knockout animals. Our interpretation of these findings is that disturbed dopamine neurotransmission due to genetic D3R blockade may enhance the PACAP/PAC1-VPAC axis, a key endogenous system for the processing of fear memories. This could explain, at least in part, the facilitated acquisition and consolidation of aversive memories in D3R(-/-) mice.