The Utilization of Biospecimens: Impact of the Choice of Biobanking Model.

The term research "biobank" is one of multiple names (e.g., bioresource, biorepository,) used to designate an entity that receives, collects, processes, stores, and/or distributes biospecimens or other biospecimen-related products (e.g., data) to support research. There are multiple organizational models of biobanking used by bioresources, but the primary goal of all bioresources should not be simply to collect biospecimens, but ultimately to distribute almost all collected biospecimens and/or data to support scientific research; bioresources should serve as "biodistributors" rather than "biovaults." The appropriate choice of model is the first step in ensuring optimal biospecimen utilization by a bioresource. This article discusses some of the different models that may be used alone or in combination by a bioresource providing biospecimens for research; it describes the factors affecting the choice of the most appropriate model or models, the advantages and disadvantages of the various models, and a discussion of the impact of the choice of the model on biospecimen utilization. Frequently, problems with biospecimen utilization are not caused by any single model, but rather a mismatch between the choice of model and goals of the bioresource, and/or problems with the subsequent design, goals, operations, and management of the bioresource after a model is selected.

Biological, Medical, and Other Tissue Variables Affecting Biospecimen Utilization.

Bioresources are critical resources that support biomedical research because of their ability to appropriately collect, process, store, and distribute a wide range of high-quality biospecimens that meet the needs of specific investigators. Of note, some biorepositories are concerned by their growing inventories and their low rates of tissue utilization. This review discusses the technical characteristics of biospecimens that can cause morphological and molecular variability and/or limit the usefulness of biospecimens in research. This article also describes current challenges related to biospecimen characteristics that may affect biospecimen utilization. These include inadequate awareness of investigators about the availability of biospecimens with specific morphologic and molecular features, donor variability, preanalytical variables, technical problems inherent with an investigator's request for biospecimens, limited tissue availability from a biorepository based on requested sizes and/or numbers of available biospecimens, effects of times of warm and cold ischemia, damage of tissues during surgery, and molecular changes during storage. To ensure maximal biospecimen utilization of all types of biospecimens requires continual education of investigators from diverse fields, particularly on factors that cause variability in the morphological and molecular characteristics of tissues. The investigators' requests for biospecimens and associated data should be reviewed carefully, including by a bioresource-associated pathologist. Queries arising from the request/application form should be resolved by bioresource personnel directly with the investigator.

Optoacoustic imaging identifies ovarian cancer using a microenvironment targeted theranostic wormhole mesoporous silica nanoparticle.

At the intersection of the newly emerging fields of optoacoustic imaging and theranostic nanomedicine, promising clinical progress can be made in dismal prognosis of ovarian cancer. An acidic pH targeted wormhole mesoporous silica nanoparticle (V7-RUBY) was developed to serve as a novel tumor specific theranostic nanoparticle detectable using multispectral optoacoustic tomographic (MSOT) imaging. We report the synthesis of a small, < 40 nm, biocompatible asymmetric wormhole pore mesoporous silica core particle that has both large loading capacity and favorable release kinetics combined with tumor-specific targeting and gatekeeping. V7-RUBY exploits the acidic tumor microenvironment for tumor-specific targeting and tumor-specific release. In vitro, treatment with V7-RUBY containing either paclitaxel or carboplatin resulted in increased cell death at pH 6.6 in comparison to drug alone (p < 0.0001). In orthotopic ovarian xenograft mouse models, V7-RUBY containing IR780 was specifically detected within the tumor 7X and 4X higher than the liver and >10X higher than in the kidney using both multispectral optoacoustic tomography (MSOT) imaging with secondary confirmation using near infrared fluorescence imaging (p < 0.0004). The V7-RUBY system carrying a cargo of either contrast agent or an anti-neoplastic drug has the potential to become a theranostic nanoparticle which can improve both diagnosis and treatment of ovarian cancer.

Phosphodiesterase 10A is overexpressed in lung tumor cells and inhibitors selectively suppress growth by blocking ß-catenin and MAPK signaling.

Phosphodiesterase 10A (PDE10) is a cyclic nucleotide (e.g. cGMP) degrading enzyme highly expressed in the brain striatum where it plays an important role in dopaminergic neurotransmission, but has limited expression and no known physiological function outside the central nervous system. Here we report that PDE10 mRNA and protein levels are strongly elevated in human non-small cell lung cancer cells and lung tumors compared with normal human airway epithelial cells and lung tissue, respectively. Genetic silencing of PDE10 or inhibition by small molecules such as PQ10 was found to selectively inhibit the growth and colony formation of lung tumor cells. PQ10 treatment of lung tumor cells rapidly increased intracellular cGMP levels and activated cGMP-dependent protein kinase (PKG) at concentrations that inhibit lung tumor cell growth. PQ10 also increased the phosphorylation of ß-catenin and reduced its levels, which paralleled the suppression of cyclin D1 and survivin but preceded the activation of PARP and caspase cleavage. PQ10 also suppressed RAS-activated RAF/MAPK signaling within the same concentration range and treatment period as required for cGMP elevation and PKG activation. These results show that PDE10 is overexpressed during lung cancer development and essential for lung tumor cell growth in which inhibitors can selectively induce apoptosis by increasing intracellular cGMP levels and activating PKG to suppress oncogenic ß-catenin and MAPK signaling.

Effects of Cold Ischemia on Gene Expression: A Review and Commentary.

Frequently investigators request that tissues be collected and processed in less than one hour following removal from a patient. Some biorepositories expend significant personnel time and other resources in trying to meet such goals; however, it is unclear whether the perceived benefits of relatively short cold ischemia times warrant these added costs. The literature of human surgical tissues prospectively exposed to cold ischemia at several time points was reviewed to compare the changes in transcripts/genes and microRNA with time of cold ischemia. Also, reports of protein changes in response to cold ischemia were correlated to changes in genes. The literature is limited; however, for most tissues, only a small proportion of transcripts/genes (<1%) changes up to 3 hours following surgery and most transcripts increase rather than decrease in less than 2 hours of cold ischemia. Biorepositories and investigators must consider the literature for evidence of significant changes in molecular results from tissues before spending significant resources on relatively rapid collection of tissues to meet cold ischemia times of less than 3 hours. Instead, those using human tissues in research must consider if the cold ischemia times affect their use in specific research; hence are these tissues "fit for purpose?"

Factors Affecting the Use of Human Tissues in Biomedical Research: Implications in the Design and Operation of a Biorepository.

The availability of high-quality human tissues is necessary to advance medical research. Although there are inherent and induced limitations on the use of human tissues in research, biorepositories play critical roles in minimizing the effects of such limitations. Specifically, the optimal utilization of tissues in research requires tissues to be diagnosed accurately, and the actual specimens provided to investigators must be carefully described (i.e., there must be quality control of each aliquot of the tissue provided for research, including a description of any damage to tissues). Tissues also should be collected, processed, stored, and distributed (i.e., handled) uniformly under a rigorous quality management system (QMS). Frequently, tissues are distributed to investigators by tissue banks which have collected, processed, and stored them by standard operating procedures (SOPs). Alternatively, tissues for research may be handled via SOPs that are modified to the specific requirements of investigators (i.e., using a prospective biorepository model). The primary goal of any type of biorepository should be to ensure its specimens are of high quality and are utilized appropriately in research; however, approaches may vary based on the tissues available and requested. For example, extraction of specific molecules (e.g., microRNA) to study molecular characteristics of a tissue may require less clinical annotation than tissues that are utilized to identify how the molecular expression might be used to clarify a clinical outcome of a disease or the response to a specific therapy. This review focuses on the limitations of the use of tissues in research and how the design and operations of a tissue biorepository can minimize some of these limitations.

The effect of antigen retrieval on cells fixed in 10% neutral buffered formalin followed by transfer to 70% ethanol.

Fixation in 10% neutral buffered formalin prior to transfer to 70% ethanol for one week has been shown to adequately preserve immunorecognition of PCNA, cytokeratins AE1/AE3 and EGFr. This study investigated whether 12 hrs fixation in 10% NBF plus transfer to 70% ethanol for 4 weeks would similarly preserve immunorecognition to an extent where antigen retrieval (AR) used to reverse the masking effects of fixation on some antigens would not be necessary. Two cell lines, DU145 and SKOV3 were grown on coverslips and fixed either for 684 hrs in 10% NBF or for 12 hrs in 10% NBF which was then replaced with 70% ethanol for 672 hrs. The second experiment had the same design except an additional set of cells were subjected to heat-induced AR concomitantly. PCNA, cytokeratins AE1/AE3, and EGFr (membrane and cytoplasmic) were used to evaluate the effects of immunorecognition. Fixation in 10% NBF for 12 hrs plus transfer to 70% ethanol for 672 hrs did not preserve immunorecognition of PCNA adequately in either cell lines. Cytokeratins immunoreactivity was preserved by transfer to 70% ethanol. Cytoplasmic EGFr antigens were not adversely affected by 10% NBF fixation in either cell line and transfer to 70% ethanol had limited effects. With AR, there was little recovery of PCNA immunorecognition on cells fixed in only 10% NBF, but almost complete recovery for cells transferred to 70% ethanol. For cytokeratins there was complete recovery of immunorecognition either with only 10% NBF or 12 hrs plus transfer to 70% ethanol. For EGFr, AR resulted in complete loss of immunorecognition following either treatment. This study indicated that 12 hrs of fixation in 10% NBF plus transfer to 70% ethanol for 4 weeks with AR resulted in recovery of immunorecognition for PCNA and cytokeratins, but standard methods of AR caused loss of immunorecognition of EGFr.