Short peptides based on the conserved regions of MIEN1 protein exhibit anticancer activity by targeting the MIEN1 signaling pathway

Migration and invasion enhancer 1 (MIEN1) overexpression characterizes several cancers and facilitates cancer cell migration and invasion. Leveraging conserved immunoreceptor tyrosine-based activation motif and prenylation motifs within MIEN1, we identified potent anticancer peptides. Among them, bioactive peptides LA3IK and RP-7 induced pronounced transcriptomic and protein expression changes at sub-IC50 concentrations. The peptides effectively inhibited genes and proteins driving cancer cell migration, invasion, and epithelial-mesenchymal transition pathways, concurrently suppressing epidermal growth factor-induced nuclear factor kappa B nuclear translocation in metastatic breast cancer cells. Specifically, peptides targeted the same signal transduction pathway initiated by MIEN1. Molecular docking and CD spectra indicated the formation of MIEN1-peptide complexes. The third-positioned isoleucine in LA3IK and CVIL motif in RP-7 were crucial for inhibiting breast cancer cell migration. This is evident from the limited migration inhibition observed when MDA-MB-231 cells were treated with scrambled peptides LA3IK SCR and RP-7 SCR. Additionally, LA3IK and RP-7 effectively suppressed tumor growth in an orthotopic breast cancer model. Notably, mice tolerated high intraperitoneal (ip) peptide doses of 90 mg/Kg well, surpassing significantly lower doses of 5 mg/Kg intravenously (iv) and 30 mg/Kg intraperitoneally (ip) used in both in vivo pharmacokinetic studies and orthotopic mouse model assays. D-isomers of LA3IK and RP-7 showed enhanced anticancer activity compared to their L-isomers. D-LA3IK remained stable in mouse plasma for 24 h with 75% remaining, exhibiting superior pharmacokinetic properties over D/L-RP-7. In summary, our findings mark the first report of short peptides based on MIEN1 protein sequence capable of inhibiting cancer signaling pathways, effectively impeding cancer progression both in vitro and in vivo.

Cabazitaxel-Loaded Nanoparticles Reduce the Invasiveness in Metastatic Prostate Cancer Cells: Beyond the Classical Taxane Function

Bone-metastatic prostate cancer symbolizes the beginning of the later stages of the disease. We designed a cabazitaxel-loaded, poly (lactic-co-glycolic acid) (PLGA) nanoparticle using an emulsion-diffusion-evaporation technique. Bis (sulfosuccinimidyl) suberate (BS3) was non-covalently inserted into the nanoparticle as a linker for the conjugation of a bone-targeting moiety to the outside of the nanoparticle. We hypothesized that the nanoparticles would have the ability to inhibit the epithelial-to-mesenchymal transition (EMT), invasion, and migration in prostate cancer cells. Targeted, cabazitaxel-loaded nanoparticles attenuated the EMT marker, Vimentin, and led to an increased E-cadherin expression. These changes impart epithelial characteristics and inhibit invasive properties in cancer progression. Consequently, progression to distant sites is also mitigated. We observed the reduction of phosphorylated Src at tyrosine 416, along with increased expression of phosphorylated cofilin at serine 3. These changes could affect migration and invasion pathways in cancer cells. Both increased p-120 catenin and inhibition in IL-8 expression were seen in targeted, cabazitaxel-loaded nanoparticles. Overall, our data show that the targeted, cabazitaxel-loaded nanoparticles can act as a promising treatment for metastatic prostate cancer by inhibiting EMT, invasion, and migration, in prostate cancer cells.

Bioinspired Nanoparticles Engineered for Enhanced Delivery to the Bone

Targeting therapeutic agents to specific organs in the body remains a challenge despite advances in the science of systemic drug delivery. We have engineered a programmable-bioinspired nanoparticle (P-BiNP) delivery system to simultaneously target the bone and increase uptake in homotypic tumor cells by coating polymeric nanoparticles with programmed cancer cell membranes. This approach is unique in that we have incorporated relevant clinical bioinformatics data to guide the design and enhancement of biological processes that these nanoparticles are engineered to mimic. To achieve this, an analysis of RNA expression from metastatic prostate cancer patients identified ITGB3 (a subunit of integrin α _V β ₃) as overexpressed in patients with bone metastasis. Cancer cells were stimulated to increase this integrin expression on the cell surface, and these membranes were subsequently used to coat cargo carrying polymeric nanoparticles. Physicochemical optimization and characterization of the P-BiNPs showed desirable qualities regarding size, ζ potential, and stability. In vitro testing confirmed enhanced homotypic binding and uptake in cancer cells. P-BiNPs also demonstrated improved bone localization in vivo with a murine model. This novel approach of identifying clinically relevant targets for dual homotypic and bone targeting has potential as a strategy for treatment and imaging modalities in diseases that affect the bone as well as broader implications for delivering nanoparticles to other organs of interest.

Evidence-based approaches to reduce cancer health disparities: Discover, develop, deliver, and disseminate

The Texas Center for Health Disparities (TCHD) at the University of North Texas Health Science Center is a National Institute on Minority Health and Health Disparities-funded, specialized center of excellence for health disparities. TCHD organized its 12^th annual conference focusing on "Evidence-Based Approaches to Reduce Cancer Health Disparities: Discover, Develop, Deliver, and Disseminate." At this conference, experts in health care, biomedical sciences, and public health gathered to discuss the current status and strategies for reducing cancer health disparities. The meeting was conducted in three sessions on breast cancer, prostate cancer, and colorectal cancer disparities, in addition to roundtable discussions and a poster session. Each session highlighted differences in the effects of cancer, based on factors such as race/ethnicity, gender, socioeconomic status, and geographical location. In each session, expert speakers presented their findings, and this was followed by a discussion panel made up of experts in that field and cancer survivors, who responded to questions from the audience. This article summarizes the approaches to fundamental, translational, clinical, and public health issues in cancer health disparities discussed at the conference.

Abstract 4399: Utilizing cobalt coordination chemistry as a traceless prodrug strategy in targeted drug delivery

We recently reported the synthesis of albumin nanoparticles using cobalt as a traceless, reductively labile crosslinker. Here, we report in vitro characterization of particle uptake for fluorescently labeled cobalt crosslinked albumin nanoparticles (Co-Alb-FITC NPs) via image-based flow cytometry as well as preliminary toxicity data. Uptake of Co-Alb-FITC NPs by gastric carcinoma cells (SNU-5) was rapid, but could be dramatically reduced through the addition of an inhibitor of macropinocytosis. High levels of non-specific uptake of other particle types were also observed suggesting SNU-5 cells possess high macropinocytic activity. Cancers harboring mutated Ras (>20% of all cancers) are known to take up protein via macropinocytosis to satisfy metabolic demands. Because SNU-5 cells are not known harbor mutated Ras, our findings may indicate that other cancers rely on this mechanism as well, which would have important implications for observing selectivity in active nanoparticle targeting strategies. The Co-Alb NPs themselves were found to exhibit no inherent toxicity. Based on these initial findings, Co-Alb NPs were loaded with the active metabolite of camptothecin, SN-38, to explore their potential as a delivery vector for hydrophobic drugs. An albumin-topotecan prodrug conjugate was also synthesized by crosslinking the amine group in topotecan with lysine residues in the protein, which should be applicable to other amine-containing therapeutics. Characterization of drug loading and release will be discussed along with preliminary in vitro characterization.

Citation Format: Robby A. Petros, Duong T. Nguyen, Ronaldo J. Cavazos, Clifford S. Morrison, Jana B. Lampe, Alesha N. Harris, Brian K. McFarlin. Utilizing cobalt coordination chemistry as a traceless prodrug strategy in targeted drug delivery. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 4399. doi:10.1158/1538-7445.AM2015-4399

Analysis of the polymorphic prion protein gene codon 129 in idiopathic Parkinson's disease

Idiopathic Parkinson's disease (IPD) is a neurodegenerative disorder of unknown aetiology. Histopathological similarities between IPD and Creutzfeldt-Jakob prion disease (CJD) have been suggested. Homozygosity at polymorphic prion protein gene codon 129 (PRNP129) is a risk factor for developing CJD. Therefore we investigated a putative genetic link between CJD and IPD by studying PRNP129 genotype segregation in 81 patients with IPD. We did not ascertain a different PRNP129 genotype distribution in IPD patients compared to healthy Germans. We found a significant difference in PRNP129 genotype in dependence of the clinical predominance type of IPD. Patients with tremor-dominant IPD presented less frequent a methionine homozygosis at PRNP129 than hypokinetic-rigid IPD patients (30% versus 62.5%; p<0.033). In conclusion, genotype distribution at codon 129 is obviously not essential in determining IPD. But our results may provide first evidence of an association between certain PRNP129 polymorphisms and the clinical presentation of IPD.

Apolipoprotein E and alpha-1-antichymotrypsin polymorphisms in sporadic inclusion body myositis

Sporadic inclusion body myositis (s-IBM) is a progressive muscle disease of unknown aetiology. Characteristically, intracellular amyloid deposits are detectable, including beta-amyloid precursor protein, phosphorylated tau, alpha1-antichymotrypsin (alpha1-ACT) and apolipoprotein E (ApoE). Polymorphisms and mutations of the encoding genes have been identified in a variety of neurodegenerative diseases including Alzheimer's disease (AD). Beside other factors, polymorphisms may lead to protein accumulation in both diseases. In particular, polymorphisms within the ApoE and alpha1-ACT gene have been implicated in the aetiology of AD and s-IBM. We analysed ApoE and alpha1-ACT gene polymorphisms in 35 s-IBM patients. We could not identify any statistical significant correlation between distinct ApoE and alpha1-ACT genotypes and the risk of developing s-IBM. Additionally, ApoE and alpha1-ACT genotypes seem not to influence the onset age of s-IBM. A combination of different alpha1-ACT and ApoE genotypes appears not to enhance the risk of developing s-IBM. Therefore, allelic variations of alpha1-ACT and ApoE are unlikely to be genetic key factors in the aetiology of s-IBM.

HLA typing and Parkinson's disease

Idiopathic Parkinson's disease (IPD) is a neurodegenerative disorder of unknown aetiology. Several antigens have been associated with IPD using serological methods. We systematically analysed HLA class I and II alleles in 45 German Caucasian IPD patients using sequence-specific oligonucleotides and sequence-specific primer technology. Applying Bonferroni adjusted p values, we demonstrate a statistically significant increase of the DQB1*06 allele (p = 0.002) in IPD which may indicate an association between IPD and the immune system. Alternatively, HLA alleles might be in linkage disequilibrium with genes located next to the HLA locus.

Expression of the interferon-induced MxA protein in viral encephalitis

MxA protein accumulates cytoplasmically in response to interferon stimulation, and mediates resistance against several viruses. In order to test whether MxA may serve as a diagnostic tool for viral infections of the central nervous system (CNS), we performed MxA immunohistochemistry on biopsies and autopsies of 57 patients with neurological disorders of known viral and nonviral aetiology. MxA was detectable in all HIV patients with proven opportunistic viral encephalitis, in all patients suffering from isolated viral encephalitis, in one of three HIV patients with cerebral toxoplasmosis, and in one case of micronodular encephalitis. No MxA was detectable in HIV patients with isolated HIV encephalitis or HIV infection accompanied by an opportunistic nonviral disorder. We were unable to show MxA expression in a variety of nonviral inflammatory and noninflammatory disorders of the CNS. Several cases of Rasmussen's encephalitis and multiple sclerosis tested negative, arguing against their possible viral aetiology. Two-colour immunohistochemistry identified macrophages and activated microglia as MxA expressing cells. In all studied cases MxA expression was accompanied by a marked T-cell infiltrate. Therefore, the detection of MxA-protein is a sensitive adjuvant marker for those cases of viral encephalitis which are accompanied by pronounced lymphocytic infiltrates.

[Proximal weakness and exercise-induced pain as initial symptom of oculopharyngeal muscular dystrophy]

A 54-year-old female patient presented with exercise-induced proximal muscle pain and weakness of the lower limbs. One year after the onset of these symptoms she developed bilateral ptosis and dysphagia. Molecular genetic analysis of the poly(A) binding protein 2 gene (PABP2) confirmed the presumptive diagnosis of oculopharyngeal muscular dystrophy (OPMD). Exercise-induced proximal muscle pain and weakness are rarely initial symptoms of OPMD. We discuss therapeutic options and present an overview of the relevant literature.

Randomized, single-blinded comparative study of the efficacy of amoxicillin (40 mg/kg/day) versus standard-dose penicillin V in the treatment of group A streptococcal pharyngitis in children

A 10-day course of amoxicillin at a dosage of 40 mg per kilogram per day was compared with conventional (lower dosage) penicillin V therapy in the treatment of culture-proven Group A streptococcal pharyngitis in children 3 to 18 years of age in a prospective, randomized, and single-blinded study. Children had to have signs and symptoms compatible with the diagnosis of streptococcal pharyngitis and to have a throat swab positive for Group A streptococci. A second throat culture was obtained 10 to 14 days after the completion of therapy. Serotyping was performed to help differentiate carrier states from reinfections. Of 161 children enrolled, 113 were evaluable; 55 received penicillin and 58 received amoxicillin. At the completion of therapy 70.9% (39/55) of patients in the penicillin group vs 87.9% (51/58) of patients in the amoxicillin group were asymptomatic (clinical cure, P = 0.025). At the completion of therapy, 54.5% (30/55) of patients in the penicillin group vs 79.3% (46/58) of patients in the amoxicillin group had negative throat cultures (bacteriologic cure, P = 0.005). The carrier rate (children who were well but who were still carrying the same serotype of Group A streptococcus) also differed between the groups: 13 (23.6%) in the penicillin group compared with six (10.3%) in the amoxicillin group. Amoxicillin at 40 mg/kg/day was significantly more effective than lower dosages of penicillin V for clinical and bacteriologic cure in the treatment of Group A streptococcal pharyngitis in children. The current perception that penicillin is declining in effectiveness may be due to inadequate dosing.

The effect of prolonged bottle feeding on cow's milk intake and iron stores at 18 months of age

Thirty-four toddlers were studied in a prospective, convenience sample comparison at their 18-month health supervision visit to examine the effect of prolonged (i.e., to 18 months of age) bottle feeding on both the daily volume of cow's milk intake and the toddler's iron stores (serum ferritin concentrations.) Seventeen toddlers had been weaned from the bottle by approximately 1 year of age, and 17 toddlers who remained on the bottle at 18 months of age were the compared group. The toddlers who remained on the bottle had significantly greater (P < 0.001) cow's milk intake (mean 26.3 oz vs 16.1 oz). The mean ferritin concentrations were lower in the persistent bottle group (17.3 micrograms/L vs 23.4 micrograms/L), but not significantly so. Questioning parents about their toddlers' continued bottle use at 18 months can provide a marker for potentially excessive cow's milk intake.