Formulation optimization of lyophilized aptamer-gold nanoparticles: Maintained colloidal stability and cellular uptake.

Anti-nucleolin (NCL) aptamer AS1411 is the first anticancer aptamer tested in clinical trials. Gold nanoparticles (AuNP) have been widely exploited for various biomedical applications due to their unique functional properties. In this study, we evaluated the colloidal stability and targeting capacity of AS1411-funtionalized AuNP (AuNP/NCL-Apt) against MCF-7 breast cancer cell line before and after lyophilization. Trehalose, mannitol, and sucrose at various concentrations were evaluated to determine their cryoprotection effects. Our results indicate that sucrose at 10 % (w/v) exhibits the best cryoprotection effect and minimal AuNP/NCL-Apt aggregation as confirmed by UV-Vis spectroscopy and dynamic light scattering (DLS) measurements. Moreover, the lyophilized AuNP/NCL-Apt at optimized formulation maintained its targeting and cytotoxic functionality against MCF-7 cells as proven by the cellular uptake assays utilizing flow cytometry and confocal laser scanning microscopy (CLSM). Quantitative PCR (qPCR) analysis of nucleolin-target gene expression also confirmed the effectiveness of AuNP/NCL-Apt. This study highlights the importance of selecting the proper type and concentration of cryoprotectant in the typical nanoparticle lyophilization process and contributes to our understanding of the physical and biological properties of functionalized nanoparticles upon lyophilization.

Clinical and molecular characteristics of Jordanian oropharyngeal cancer patients according to P16 expression: a retrospective study and a report of a novel biomarker.

The purpose of this study was to assess the clinicopathological features of oropharyngeal cancer patients in Jordan based on their HPV status. Sixty-nine biopsies from two hospitals were included. Tissue microarrays were prepared from formalin-fixed paraffin-embedded (FFPE) specimens and stained with antibodies for CDKN2A/P16, EGFR, PI3K, PTEN, AKT, pS473AKT, PS2mTOR, and TIMAP. The cohort was divided according to P16 expression. Chi-square test and survival analyses were employed to evaluate the variations among the study variables and determine the prognostic factors, respectively. P16 expression was found in 55.1% of patients; however, there was no significant association between P16 expression and the patients' clinicopathological features. The Kaplan-Meier test revealed that smoking in P16-positive group and younger age (< 58 years) negatively impacted disease-free survival (DFS) (P = 0.04 and P = 0.003, respectively). Multivariate Cox regression test indicated that smoking, age, PI3K, and AKT were negative predictors of DFS (P = 0.021, P = 0.002, P = 0.021, and P = 0.009, respectively), while TIMAP was a positive predictor (P = 0.045). Elevated P16 expression is found in more than half of the patients' specimens. DFS is negatively affected by younger age and the combined effect of smoking and P16 overexpression. TIMAP is overexpressed in P16-positive oropharyngeal cancer, and it is a favorable predictor of DFS.

Prevalence and characteristics of long COVID-19 in Jordan: A cross sectional survey.

Early in the pandemic, the spread of the emerging virus SARS-CoV-2 was causing mild illness lasting less than two weeks for most people, with a small proportion of people developing serious illness or death. However, as the pandemic progressed, many people reported suffering from symptoms for weeks or months after their initial infection. Persistence of COVID-19 symptoms beyond one month, or what is known as long COVID-19, is recognized as a risk of acute infection. Up to date, information on long COVID-19 among Jordanian patients has not been reported. Therefore, we sought to conduct this cross-sectional study utilizing a self-administered survey. The survey asks a series of questions regarding participant demographics, long COVID-19 symptoms, information about pre-existing medical history, supplements, vaccination history, and symptoms recorded after vaccination. Chi square analysis was conducted on 990 responders, and the results showed a significant correlation (P<0.05) between long COVID-19 syndrome and age, obesity, chronic illness, vitamin D intake, number of times infected by COVID-19, number of COVID-19 symptoms and whether the infection was pre or post vaccination. The long-term symptoms most enriched in those with long COVID-19 were tinnitus (73.4%), concentration problems (68.6%) and muscle and joint ache (68.3%).A binomial logistic regression analysis was done to explore the predictors of long COVID-19 and found that age 18-45, marital status, vitamin D, number of COVID-19 symptoms and signs after vaccination are positive predictors of long COVID-19, while zinc intake is a negative predictor. Although further studies on long-term persistence of symptoms are needed, the present study provides a baseline that allows us to understand the frequency and nature of long COVID-19 among Jordanians.

Correlation of PKM2 Expression With HER2/neu and Additional Breast Cancer Biomarkers and its Prognostic Significance.

BACKGROUND: Pyruvate kinase M2 (PKM2) has a central role in both tumor development and metastasis, and it has increasingly become a valuable subject for many cancer studies due to its important prognostic value in various tumor types. In this study, we aimed to elucidate the impact of PKM2 expression level on breast cancer prognosis and survival rates and its association with various clinicopathologic characteristics and tumor markers in breast cancer patients. MATERIALS AND METHODS: This retrospective study included sample tissues from patients with breast cancer who did not receive chemotherapy or radiotherapy before surgery. Expression levels of PKM2, estrogen receptor, progesterone receptor, human epidermal growth factor receptor 2 (HER2), and Ki-67 were analyzed using tissue microarray and immunohistochemistry. RESULTS: A total of 164 patients were included with an age range from 28 to 82 years. High PKM2 was observed in 48.8% of cases (80/164). A significant association was found between PKM2 expression and breast cancer molecular subtype and HER2 status ( P <0.001). In HER2-negative tumors, there was a significant association between PKM2 expression and tumor grade, TNM stage, pN stage, lymphovascular invasion, and estrogen receptor/progesterone receptor status. Survival analysis revealed that high PKM2 expression levels were associated with decreased overall survival rate in HER2-positive cases with high Ki-67 index. Moreover, in the HER2-positive group, low PKM2 expression level impacted the survival outcome of metastasis ( P =0.002). CONCLUSIONS: PKM2 is a valuable prognostic and a potential diagnostic and predictive marker in breast cancer. Moreover, the combination of PKM2 with Ki-67 provides excellent prognostic accuracy in HER2-positive tumors.

The modulation of Plasma Levels of Dopamine, Serotonin, and Brain-derived neurotrophic factor in response to variation in iron availability.

BACKGROUND AND AIM: In the context of iron deficiency anemia, central dopamine, serotonin, and brain-derived neurotrophic factor (BDNF) are intensively investigated. However, peripheral isoforms are poorly investigated. This study aimed to investigate the modulation of plasma levels of dopamine, serotonin, and BDNF among children with iron deficiency anemia. METHODS: A total of seventy-three iron-deficient (n=38) and iron-sufficient (n=35) children were included in the study.  Twenty-nine subjects were showing clinical presentations and were diagnosed with iron deficiency anemia and forty-four were asymptomatic normal children. Plasma levels of dopamine, serotonin, and brain-derived neurotrophic factor were determined by enzyme-linked immunosorbent assay. RESULTS: As compared to corresponding levels among control subjects, Anemic subjects were having significantly higher plasma dopamine and lower plasma brain-derived neurotrophic factor levels. A significant linear and monotonic association of plasma dopamine and brain-derived neurotrophic factor with hemoglobin concentration (r=-0.520, P < 0.001 and ρ = 0.411, P = 0.001), respectively. Furthermore, there were significantly higher plasma serotonin levels among iron-deficient subjects with a significant inverse linear association with serum ferritin levels (r = -0.337, P = 0.005). CONCLUSIONS: Iron deficiency anemia is associated with the modulation of peripheral dopamine, serotonin, and brain-derived neurotrophic factor. Upregulation of dopamine and downregulation of brain-derived neurotrophic factor are correlated to the anemic status. The upregulation of plasma serotonin levels is iron-dependent and, probably, is attributed to the impairment of its metabolic fate. Further investigation is required to explore the pathophysiological and clinical association of these peripheral biomolecules in the context of iron deficiency anemia. (www.actabiomedica.it).

TIMAP Upregulation Correlates Negatively with Survival in HER2- Negative Subtypes of Breast Cancer.

OBJECTIVE: TIMAP expression is regulated by transforming growth factor beta 1 (TGFß1); known for its role in breast cancer development and metastasis. Nevertheless, data on TIMAP protein expression and its association with breast cancer development are lacking. In this study, we aimed to investigate the variation in TIMAP protein expression in breast cancer tissue and its correlation with various clinicopathological characteristics of breast cancer patients and overall survival rate. METHODS: A total of 159 paraffin-embedded tissue blocks from women diagnosed with four breast cancer subtypes (49 HER2-only, 33 Luminal A, 39 Luminal B, and 38 triple negative) were used to construct tissue microarray (TMA), followed by TIMAP immunohistochemistry (IHC). TIMAP expression was scored by two pathologists and categorized as weak (1-33% expression), moderate (34-66%), and strong (67-100%). Chi-square test and Kaplan Meier survival test were performed to determine the association between TIMAP expression and clinicopathological features and overall survival rate, respectively. RESULTS: TIMAP protein was strongly expressed in 46 (93.9%) HER2-only, 32 (97%) luminal A, 37 (94.9%) luminal B, and 29 (76.3%) triple negative. TIMAP expression negatively associated with ER/PR expression (P=0.03), and it negatively impacted the overall survival in HER2 negative group (P=0.02). CONCLUSION: Our findings suggest that TIMAP protein expression is upregulated in all breast cancer subtypes. However, its prognostic role is exclusively observed in HER2- negative group, suggesting a potential of targeting TIMAP in future therapeutic strategies in this group.

TIMAP inhibits endothelial myosin light chain phosphatase by competing with MYPT1 for the catalytic protein phosphatase 1 subunit PP1cß.

Transforming growth factor-ß membrane associated protein (TIMAP) is an endothelial cell (EC)-predominant PP1 regulatory subunit and a member of the myosin phosphatase target (MYPT) protein family. The MYPTs preferentially bind the catalytic protein phosphatase 1 subunit PP1cß, forming myosin phosphatase holoenzymes. We investigated whether TIMAP/PP1cß could also function as a myosin phosphatase. Endogenous PP1cß, myosin light chain 2 (MLC2), and myosin IIA heavy chain coimmunoprecipitated from EC lysates with endogenous TIMAP, and endogenous MLC2 colocalized with TIMAP in EC projections. Purified recombinant GST-TIMAP interacted directly with purified recombinant His-MLC2. However, TIMAP overexpression in EC enhanced MLC2 phosphorylation, an effect not observed with a TIMAP mutant that does not bind PP1cß. Conversely, MLC2 phosphorylation was reduced in lung lysates from TIMAP-deficient mice and upon silencing of endogenous TIMAP expression in ECs. Ectopically expressed TIMAP slowed the rate of MLC2 dephosphorylation, an effect requiring TIMAP-PP1cß interaction. The association of MYPT1 with PP1cß was profoundly reduced in the presence of excess TIMAP, leading to proteasomal MYPT1 degradation. In the absence of TIMAP, MYPT1-associated PP1cß readily bound immobilized microcystin-LR, an active-site inhibitor of PP1c. By contrast, TIMAP-associated PP1cß did not interact with microcystin-LR, indicating that the active site of PP1cß is blocked when it is bound to TIMAP. Thus, TIMAP inhibits myosin phosphatase activity in ECs by competing with MYPT1 for PP1cß and blocking the PP1cß active site.

TIMAP promotes angiogenesis by suppressing PTEN-mediated Akt inhibition in human glomerular endothelial cells.

The function of TIMAP, an endothelial cell (EC)-predominant protein phosphatase 1-regulatory subunit, is poorly understood. We explored the potential role of TIMAP in the Akt-dependent regulation of glomerular EC proliferation, survival, and in vitro angiogenesis. To deplete TIMAP, the EC were transfected with TIMAP-specific or nonspecific small interfering (si) RNA. The rate of electrical impedance development across subconfluent EC monolayers, a measure of the time-dependent increase in EC number, was 93 ± 2% lower in TIMAP-depleted than in control EC. This effect on cell proliferation was associated with reduced DNA synthesis and increased apoptosis: TIMAP silencing reduced 5-ethynyl-2'-deoxyuridine incorporation by 38 ± 2% during the exponential phase of EC proliferation, and cleaved caspase 3 as well as caspase 3 activity increased in TIMAP-depleted relative to control cells. Furthermore, TIMAP depletion inhibited the formation of angiogenic sprouts by glomerular EC in three-dimensional culture. TIMAP depletion strongly diminished growth factor-stimulated Akt phosphorylation without altering ERK1/2 phosphorylation, suggesting a specific effect on the PI3K/Akt/PTEN pathway. Endogenous TIMAP and PTEN colocalized in EC and coimmunoprecipitated from EC lysates. The inhibitory PTEN phosphorylation on S370 was significantly reduced in TIMAP-depleted compared with control EC, while phosphorylation of PTEN on the S380/T382/T383 cluster remained unchanged. Finally, the PTEN inhibitor bpV(phen) fully reversed the suppressive effect of TIMAP depletion on Akt phosphorylation. The data indicate that in growing EC, TIMAP is necessary for Akt-dependent EC proliferation, survival, and angiogenic sprout formation and that this effect of TIMAP is mediated by inhibition of the tumor suppressor PTEN.

Tipping the balance from angiogenesis to fibrosis in CKD.

Chronic progressive renal fibrosis leads to end-stage renal failure many patients with chronic kidney disease (CKD). Loss of the rich peritubular capillary network is a prominent feature, and seems independent of the specific underlying disease. The mechanisms that contribute to peritubular capillary regression include the loss of glomerular perfusion, as flow-dependent shear forces are required to provide the survival signal for endothelial cells. Also, reduced endothelial cell survival signals from sclerotic glomeruli and atrophic or injured tubule epithelial cells contribute to peritubular capillary regression. In response to direct tubular epithelial cell injury, and the inflammatory reaction that ensues, capillary pericytes dissociate from their blood vessels, also reducing endothelial cell survival. In addition, direct inflammatory injury of capillary endothelial cells, for instance in chronic allograft nephropathy, also contributes to capillary dropout. Chronic tissue hypoxia, which ensues from the rarefaction of the peritubular capillary network, can generate both an angiogenic and a fibrogenic response. However, in CKD, the balance is strongly tipped toward fibrogenesis. Understanding the underlying mechanisms for failed angiogenesis in CKD and harnessing endothelial-specific survival and pro-angiogenic mechanisms for therapy should be our goal if we are to reduce the disease burden from CKD.

Multi-directional function of the protein phosphatase 1 regulatory subunit TIMAP.

TIMAP is an endothelial-cell predominant member of the MYPT family of PP1c regulatory subunits. This study explored the TIMAP-PP1c interaction and substrate specificity in vitro. TIMAP associated with all three PP1c isoforms, but endogenous endothelial cell TIMAP preferentially co-immunoprecipitated with PP1cß. Structural modeling of the TIMAP/PP1c complex predicts that the PP1c C-terminus is buried in the TIMAP ankyrin cluster, and that the PP1c active site remains accessible. Consistent with this model, C-terminal PP1c phosphorylation by cdk2-cyclinA was masked by TIMAP, and PP1c bound TIMAP when the active site was occupied by the inhibitor microcystin. TIMAP inhibited PP1c activity toward phosphorylase a in a concentration-dependent manner, with half-maximal inhibition in the 0.4-1.2 nM range, an effect modulated by the length, and by Ser333/Ser337 phosphomimic mutations of the TIMAP C-terminus. TIMAP-bound PP1cß effectively dephosphorylated MLC2 and TIMAP itself. By contrast, TIMAP inhibited the PP1cß activity toward the putative substrate LAMR1, and instead masked LAMR1 PKA- and PKC-phosphorylation sites. This is direct evidence that MLC2 is a TIMAP/PP1c substrate. The data also indicate that TIMAP can modify protein phosphorylation independent of its function as a PP1c regulatory subunit, namely by masking phosphorylation sites of binding partners like PP1c and LAMR1.

Glomerular endothelium: a porous sieve and formidable barrier.

The glomerular capillary endothelium is highly specialized to support the selective filtration of massive volumes of plasma. Filtration is driven by Starling forces acting across the glomerular capillary wall, and depends on its large surface area and extremely high water permeability. Glomerular endothelial cells are extremely flat and perforated by dense arrays of trans-cellular pores, the fenestrae. This phenotype is critical for the high glomerular water permeability and depends on podocyte-derived VEGF, as well as TGF-beta. Endothelial cell-derived PDGFB, in turn, is necessary for the establishment of mesangial cells, which sculpt the glomerular loop structure that underlies the large filtration surface area. In pre-eclampsia, inhibition of the VEGF- and TGF-beta signaling pathways leads to endothelial swelling and loss of fenestrae, reducing the glomerular filtration rate. Similarly, in the thrombotic microangiopathies, glomerular endothelial cell injury coupled with inappropriate VWF activation leads to intracapillary platelet aggregation and loss of the flat, fenestrated phenotype, thus reducing the glomerular filtration rate. Normally, a remarkably small fraction of albumin and other large plasma proteins passes across the glomerular capillary wall despite the massive filtration of water and small solutes. An elaborate glycocalyx, which covers glomerular endothelial cells and their fenestrae forms an impressive barrier that, together with other components of the glomerular capillary wall, prevents loss of plasma proteins into the urine. Indeed, microalbuminuria is a marker for endothelial glycocalyx disruption, and most forms of glomerular endothelial cell injury including pre-eclampsia and thrombotic microangiopaties can cause proteinuria.

CLIC5A, a component of the ezrin-podocalyxin complex in glomeruli, is a determinant of podocyte integrity.

The chloride intracellular channel 5A (CLIC5A) protein, one of two isoforms produced by the CLIC5 gene, was isolated originally as part of a cytoskeletal protein complex containing ezrin from placental microvilli. Whether CLIC5A functions as a bona fide ion channel is controversial. We reported previously that a CLIC5 transcript is enriched approximately 800-fold in human renal glomeruli relative to most other tissues. Therefore, this study sought to explore CLIC5 expression and function in glomeruli. RT-PCR and Western blots show that CLIC5A is the predominant CLIC5 isoform expressed in glomeruli. Confocal immunofluorescence and immunogold electron microscopy reveal high levels of CLIC5A protein in glomerular endothelial cells and podocytes. In podocytes, CLIC5A localizes to the apical plasma membrane of foot processes, similar to the known distribution of podocalyxin and ezrin. Ezrin and podocalyxin colocalize with CLIC5A in glomeruli, and podocalyxin coimmunoprecipitates with CLIC5A from glomerular lysates. In glomeruli of jitterbug (jbg/jbg) mice, which lack the CLIC5A protein, ezrin and phospho-ERM levels in podocytes are markedly lower than in wild-type mice. Transmission electron microscopy reveals patchy broadening and effacement of podocyte foot processes as well as vacuolization of glomerular endothelial cells. These ultrastructural changes are associated with microalbuminuria at baseline and increased susceptibility to adriamycin-induced glomerular injury compared with wild-type mice. Together, the data suggest that CLIC5A is required for the development and/or maintenance of the proper glomerular endothelial cell and podocyte architecture. We postulate that the interaction between podocalyxin and subjacent filamentous actin, which requires ezrin, is compromised in podocytes of CLIC5A-deficient mice, leading to dysfunction under unfavorable genetic or environmental conditions.