Diagnosis of traumatic brain injury using miRNA signatures in nanomagnetically isolated brain-derived extracellular vesicles.

The accurate diagnosis and clinical management of traumatic brain injury (TBI) is currently limited by the lack of accessible molecular biomarkers that reflect the pathophysiology of this heterogeneous disease. To address this challenge, we developed a microchip diagnostic that can characterize TBI more comprehensively using the RNA found in brain-derived extracellular vesicles (EVs). Our approach measures a panel of EV miRNAs, processed with machine learning algorithms to capture the state of the injured and recovering brain. Our diagnostic combines surface marker-specific nanomagnetic isolation of brain-derived EVs, biomarker discovery using RNA sequencing, and machine learning processing of the EV miRNA cargo to minimally invasively measure the state of TBI. We achieved an accuracy of 99% identifying the signature of injured vs. sham control mice using an independent blinded test set (N = 77), where the injured group consists of heterogeneous populations (injury intensity, elapsed time since injury) to model the variability present in clinical samples. Moreover, we successfully predicted the intensity of the injury, the elapsed time since injury, and the presence of a prior injury using independent blinded test sets (N = 82). We demonstrated the translatability in a blinded test set by identifying TBI patients from healthy controls (AUC = 0.9, N = 60). This approach, which can detect signatures of injury that persist across a variety of injury types and individual responses to injury, more accurately reflects the heterogeneity of human TBI injury and recovery than conventional diagnostics, opening new opportunities to improve treatment of traumatic brain injuries.

Hepatotoxicity of camptothecin derivatives in a primary culture system of rat hepatocytes.

The topoisomerase I inhibitors are a new class of antineoplastic agents currently under clinical development. Among these compounds there are some camptothecin (CPT) derivatives with improved toxicity profiles and antitumor activity: irinotecan (CPT-11) and topotecan (TPT), particularly active against colon, lung and ovarian cancer. The aim of this study was to evaluate the cytotoxicity of CPT, CPT-11, its metabolite SN38 and TPT in a primary culture system of rat hepatocytes. Cytotoxicity was evaluated by measuring the leakage of lactate dehydrogenase (LDH) into the medium and by assessing cell viability in terms of tetrazolium salts (MTT) reduction by mitochondrial dehydrogenase activity. Our results showed that cytotoxicity was limited in the case of short drug exposure. There was a significant and time-dependent increase in LDH leakage and a significant time- and dose-dependent decrease in MTT reduction after 3 h of incubation (p<0.01). In the treatments with doses related to peak plasma levels, CPT-11 was less responsible for the observed in vitro hepatotoxicity than its metabolite SN38; TPT had lower LDH leakage compared to SN38 and CPT-11 but showed significant and early (3 h) decrease in MTT reduction: this may mean a different mechanism of cellular damage. These results demonstrate that CPT derivatives are directly toxic to liver cells in a distinct time- and dose-related response.

Hepatoprotective properties in the rat of Mitracarpus scaber (Rubiaceae).

The effect of Mitracarpus scaber on carbon tetrachloride-induced acute liver damage in the rat has been evaluated. Results showed that treatment with Mitracarpus scaber decoction resulted in significant hepatoprotection against CCl4-induced liver injury both in-vivo and in-vitro. In-vivo, Mitracarpus scaber pretreatment reduced levels of serum glutamate-oxalate-transaminase (P < 0.01 for 250, 500 and 1000 mg kg(-1)) and serum glutamate-pyruvate-transaminase (P < 0.05 for 250 mg kg(-1) and P < 0.01 for 1000 mg kg(-1)) previously increased by administration of CCl4. In-vitro results indicated that addition to the culture medium of Mitracarpus scaber extracts significantly reduced glutamate-oxalate-transaminase (P < 0.05 for 100 microg mL(-1) and P < 0.01 for 10 and 1000 microg mL(-1)) and lactate dehydrogenase activity (P < 0.05 for 10 microg mL(-1)). Mitracarpus treatment also resulted in a good ( > 93%) survival rate for the CCl4-intoxicated hepatocytes as demonstrated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay. Moreover, as in the in-vitro assay, Mitracarpus scaber had radical-scavenging properties, shown by its reaction with the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical (EC50, the extract concentration resulting in a 50% reduction in the absorbance of DPPH blank solution, = 41.64+/-1.5 microg mL(-1)). The results of this study showed that Mitracarpus scaber had antihepatotoxic potential, a finding which supports the validity of traditional usage of this drug in Mali for the treatment of liver diseases.

Prognostic significance of the estrogen-regulated proteins, cathepsin-D and pS2, in breast cancer.

The evaluation of prognostic factors for breast cancers is important for therapeutic decisions both at the time of surgery and during postoperative surveillance. Cathepsin-D (cath-D) is an estrogen inducible aspartyl protease. Studies have demonstrated two biological activities, at an acidic PH, of the protein: a mitogenic and a proteolytic activity; both the growth promoting activity and the extracellular proteolytic activity suggest that cathepsin D (cath-D) may have prognostic significance in breast cancer. Measurement of cath-D in breast tissue, in fact, is highly significant in predicting recurrence as well as disease free interval and overall survival. The pS2 is a small cysteine-rich protein specifically expressed under estrogen transcriptional control. Expression of the pS2 protein in breast carcinoma is a useful guide to prognosis and response to tamoxifen: appropriate adjuvant therapy can be selected on the pS2 status of the tumor; patients with pS2 expression had better overall survival and a longer survival time after the first recurrence than those without pS2 expression. For these reasons, these two new prognostic markers could be suggested as habit factors in breast cancer.

The erbB 2 oncogene and chemotherapy: a mini-review.

The erbB 2 gene, also known as Her-2/neu, is an oncogene that encodes a transmembrane glycoprotein receptor. When overexpressed erbB 2 is an indicator of poor prognosis in a number of cancers. Recent studies show that erbB 2 expression plays a role in the prediction of responsiveness to adjuvant treatment: tumors that had an overexpression of the oncogene were less responsive to treatment than those with a normal amount. Some studies on this oncogene have examined the production of anti-erbB 2 monoclonal antibodies and evaluated the combined effect of monoclonal antibody and chemotherapeutics.

Tumor-associated urokinase-type plasminogen activator: significance in breast cancer.

Urokinase-type plasminogen activator (u-PA), a proteolitic enzyme, capable of degrading type 4 collagen, is supposed to be involved in degradation of extracellular matrix during cancer invasion. Evidence has been presented that primary breast cancer patients with tumors containing high levels of u-PA experience a worse prognosis. u-PA and its inhibitor, type 1 plasminogen activator inhibitor (PAI-1), are potentially important prognostic factors in breast cancer to identify patients at high risk for recurrence and also in the classification of clinically important subgroups.

[pS2 protein and breast cancer]. / Proteina pS2 e carcinoma mammario.

pS2 is a small protein (7000 daltons) that is prevalently expressed in human breast cancer positive for estrogen receptors: protein is, in fact, induced by estrogen stimulation. Studies indicate that pS2 protein is a marker for hormone-dependent breast tumors and that its expression is helpful in the prognosis. The presence of pS2, in fact, besides being associated in 96% of the cases to the positivities for estrogen receptors, is associated with longer overall, and disease free, survival. The pS2 protein is also expressed in normal stomach mucosa; its physiological function is unknown.