The naphthoquinone pigment, shikonin, isolated from Lithospermum erythrorhizon Sieb. et Zucc.(Boraginaceae) and its derivatives are the active components isolated from the Chinese herbal therapeutic, Zicao. Historically, Zicao root extracts have been used to treat macular eruption, measles, sore-throat, carbuncles and burns. Multiple pharmacological actions have been attributed to shikonin, e.g. antiinflammatory, antigonadotropic and anti-HIV-1 activity. In this review, several therapeutic applications of shikonin will be summarized including its pleiotropic, antiinflammatory and antitumour effects. Widely diverse and sometimes conflicting activities have been attributed to shikonin, e.g. wound healing, enhanced granuloma formation, suppression of local acute inflammatory reactions, inhibition of angiogenesis, inhibition of select chemokine ligands, inhibition of DNA topoisomerase activity, inhibition of platelet activation and antimicrobial activity. Comparison of the various reported mechanisms of action for shikonin lead us to hypothesize that shikonin is an effective inhibitor of protein-protein interaction with multiple targets in both the intracellular and extracellular compartments. This general inhibitory effect can account for the broad spectrum of shikonin biological and pharmacological activities.

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The spindle and kinetochore-associated (Ska) protein complex is required for accurate chromosome segregation during mitosis [1-6] and consists of two copies each of Ska1, Ska2, and Ska3 proteins [4, 7]. The Ska complex contains multiple microtubule-binding elements and promotes kinetochore-microtubule attachment [8-11]. The Ska1 C-terminal domain (CTD) recruits protein phosphatase 1 (PP1) to kinetochores to promote timely anaphase onset [12]. The Ska complex regulates, and is regulated by, Aurora B [13]. Aurora B phosphorylates both Ska1 and Ska3 to inhibit the kinetochore localization of the Ska complex [14]. Despite its multitude of functions at kinetochores, how the Ska complex itself is recruited to kinetochores is unclear. It is unknown whether any mitotic kinases positively regulate the localization of the Ska complex to kinetochores. Here, we show that Cdk1 phosphorylates Ska3 to promote its direct binding to the Ndc80 complex (Ndc80C), a core outer kinetochore component. We also show that this phosphorylation occurs specifically during mitosis and is required for the kinetochore localization of the Ska complex. Ska3 mutants deficient in Cdk1 phosphorylation are defective in kinetochore localization but retain microtubule localization. These mutants support chromosome alignment but delay anaphase onset. We propose that Ska3 phosphorylated by Cdk1 in mitosis binds to Ndc80C and recruits the Ska complex to kinetochores where Ska1 can bind both PP1 and microtubules to promote anaphase onset.

Purpose Polymeric quick dissolving films were developed as a solid dosage topical microbicide formulation for the vaginal delivery of the highly potent and non-toxic, dual-acting HIV nonnucleoside reverse transcriptase inhibitor (NNRTI) pyrimidinedione, IQP-0528. Methods Formulated from approved excipients, a polyvinyl alcohol (PVA) based film was manufactured via solvent casting methods. The film formulations were evaluated based upon quantitative physicochemical evaluations defined by a Target Product Profile (TPP) Results Films dosed with 0.1 % (w/w) of IQP-0528 disintegrated within 10 minutes with over 50% of drug released and near 100% total drug released after 30 minutes. The IQP-0528 films were found to be non-toxic in in vitro CEM-SS and PBMC cell-based assays and biologically active with sub-nanomolar efficacy against HIV-1 infection. In a 12 month stability protocol, the IQP-0528 films demonstrated no significant degradation at International Conference on Harmonization (ICH) recommended standard (25°C / 65% relative humidity (R.H.)) and accelerated (40°C / 75% R.H.) environmental conditions. Conclusions Based on the above evaluations, a vaginal film formulation has been identified as a potential solid dosage form for the vaginal delivery of the topical microbicide candidate IQP-0528.

Ovarian cancer is the deadliest of all gynecologic malignancies. Metastatic ovarian cancer cells exist mainly in the form of multi-cellular spheroids (MCSs) in the ascites of patients with advanced ovarian cancer. We hypothesized that E-cadherin, as an important cell-adhesion molecule, might play an important role in the formation and survival of MCSs. Therefore, we established a three-dimensional suspension culture model of ovarian cancer cells that express high levels of E-cadherin to investigate their growth, proliferation, and resistance to chemotherapeutic drugs by CCK-8 assays. Compared to the cell suspension masses formed by cells with low or absent E-cadherin expression, the MCSs of high E-cadherin SKOV-3 cells had larger volumes, tighter cellular connections, and longer survival times. Although the suspension cell masses of all three cell lines were proliferatively stagnant, possibly due to cell cycle arrest at G1/S, cell mortality at 72 h after cisplatin treatment was significantly decreased in the high E-cadherin SKOV-3 cells compared to SKOV-3 cells without E-cadherin expression and to OVCAR-3 cells with low E-cadherin expression. We conclude, therefore, E-cadherin plays a vital role in MCS formation, maintenance, and drug resistance in ovarian cancer and could be a potential target for late-stage ovarian cancer treatment.

To compare the difference in white matter volume (WMV) and gray matter volume (GMV) between the comitant strabismus (CS) patients and health controls by voxel-based morphometry (VBM) and the relationship with behavioral performance. A total of 20 patients with comitant strabismus (10 males and 10 females), and 20 healthy subjects (10 males and 10 females) with matched age, sex status underwent magnetic resonance examination. The authors analyzed the original 3D T1 brain images using the VBM module. The comitant strabismus groups were compared with the control groups for the GMW and WMV of the entire brain. Correlation analysis was performed to investigate the relationship between the GMV and WMV altered areas and the behavioral performance in comitant strabismus. CS patients were distinguishable from the healthy controls (HCs) by receiver operating characteristic curves. Results of the VBM analysis demonstrated that the CS groups had decreased GMV in the brain regions of the left middle temporal pole, left cerebellum posterior lobe, right posterior cingulate cortex, left cuneus and right premotor cortex. Meanwhile, the WMV was significantly decreased in the brain regions of the left middle temporal gyrus, right middle temporal gyrus, left middle temporal gyrus, right precuneus and right premotor cortex in the comitant strabismus patients compared with HCs. Furthermore, the duration of CS was negatively correlated with the GMV values of the left middle temporal pole (r=−0.486, P=0.030). CS caused GMV and WMV atrophy in many brain regions, which may indicate the neural mechanisms of the ocular motility disorders in CS patients.

Although the effective use of highly active antiretroviral therapy results in the suppression of virus production in infected individuals, it does not eliminate the infection and low level virus production in cells harboring virus in sanctuary sites. Thus, the continued search for new antiretroviral agents with unique and different mechanisms of HIV inhibition remains critical, and compounds that can reduce the level of virus production from cells already infected with HIV, as opposed to preventing de novo infection, would be of great benefit. A mercaptobenzamide (MDH-1-38) and its prodrug (NS1040) are being developed as potential therapeutic compounds targeting the zinc finger of HIV nucleocapsid. In the presence of esterase enzymes, NS1040 is designed to be converted to MDH-1-38 which has antiviral activity. While we presume that NS1040 is rapidly converted to MDH-1-38 in all experiments, the two compounds were tested side-by-side to determine whether the presence of a prodrug affects the antiviral activity or mechanism of action. The two compounds were evaluated against a panel of HIV-1 clinical isolates in human PBMCs and monocyte-macrophages and yielded EC values ranging from 0.7 to 13 μM with no toxicity up to 100 μM. MDH-1-38 and NS1040 remained equally active in human PBMCs in the presence of added serum proteins as well as against HIV-1 isolates resistant to reverse transcriptase, integrase or protease inhibitors. Cell-based and biochemical mechanism of antiviral action assays demonstrated MDH-1-38 and NS1040 were virucidal at concentrations of 15 and 50 μM, respectively. Cell to cell transmission of HIV in multiple passages was significantly reduced in CEM-SS and human PBMCs by reducing progeny virus infectivity at compound concentrations greater than 2 μM. The combination of either MDH-1-38 or NS1040 with other FDA-approved HIV drugs yielded additive to synergistic antiviral interactions with no evidence of antiviral antagonism or synergistic toxicity. Serial dose escalation was used in attempts to select for HIV strains resistant to MDH-1-38 and NS1040. Virus at several passages failed to replicate in cells treated at increased compound concentrations, which is consistent with the proposed mechanism of action of the virus inactivating compounds. Through 14 passages, resistance to the compounds has not been achieved. Most HIV inhibitors with mechanism of antiviral action targeting a viral protein would have selected for a drug resistant virus within 14 passages. These studies indicate that these NCp7-targeted compounds represent new potent anti-HIV drug candidates which could be effectively used in combination with all approved anti-HIV drugs.